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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * vrf.c: device driver to encapsulate a VRF space
4 *
5 * Copyright (c) 2015 Cumulus Networks. All rights reserved.
6 * Copyright (c) 2015 Shrijeet Mukherjee <shm@cumulusnetworks.com>
7 * Copyright (c) 2015 David Ahern <dsa@cumulusnetworks.com>
8 *
9 * Based on dummy, team and ipvlan drivers
10 */
11
12#include <linux/ethtool.h>
13#include <linux/module.h>
14#include <linux/kernel.h>
15#include <linux/netdevice.h>
16#include <linux/etherdevice.h>
17#include <linux/ip.h>
18#include <linux/init.h>
19#include <linux/moduleparam.h>
20#include <linux/netfilter.h>
21#include <linux/rtnetlink.h>
22#include <net/rtnetlink.h>
23#include <linux/u64_stats_sync.h>
24#include <linux/hashtable.h>
25#include <linux/spinlock_types.h>
26
27#include <linux/inetdevice.h>
28#include <net/arp.h>
29#include <net/ip.h>
30#include <net/ip_fib.h>
31#include <net/ip6_fib.h>
32#include <net/ip6_route.h>
33#include <net/route.h>
34#include <net/addrconf.h>
35#include <net/l3mdev.h>
36#include <net/fib_rules.h>
37#include <net/sch_generic.h>
38#include <net/netns/generic.h>
39#include <net/netfilter/nf_conntrack.h>
40#include <net/inet_dscp.h>
41
42#define DRV_NAME "vrf"
43#define DRV_VERSION "1.1"
44
45#define FIB_RULE_PREF 1000 /* default preference for FIB rules */
46
47#define HT_MAP_BITS 4
48#define HASH_INITVAL ((u32)0xcafef00d)
49
50struct vrf_map {
51 DECLARE_HASHTABLE(ht, HT_MAP_BITS);
52 spinlock_t vmap_lock;
53
54 /* shared_tables:
55 * count how many distinct tables do not comply with the strict mode
56 * requirement.
57 * shared_tables value must be 0 in order to enable the strict mode.
58 *
59 * example of the evolution of shared_tables:
60 * | time
61 * add vrf0 --> table 100 shared_tables = 0 | t0
62 * add vrf1 --> table 101 shared_tables = 0 | t1
63 * add vrf2 --> table 100 shared_tables = 1 | t2
64 * add vrf3 --> table 100 shared_tables = 1 | t3
65 * add vrf4 --> table 101 shared_tables = 2 v t4
66 *
67 * shared_tables is a "step function" (or "staircase function")
68 * and it is increased by one when the second vrf is associated to a
69 * table.
70 *
71 * at t2, vrf0 and vrf2 are bound to table 100: shared_tables = 1.
72 *
73 * at t3, another dev (vrf3) is bound to the same table 100 but the
74 * value of shared_tables is still 1.
75 * This means that no matter how many new vrfs will register on the
76 * table 100, the shared_tables will not increase (considering only
77 * table 100).
78 *
79 * at t4, vrf4 is bound to table 101, and shared_tables = 2.
80 *
81 * Looking at the value of shared_tables we can immediately know if
82 * the strict_mode can or cannot be enforced. Indeed, strict_mode
83 * can be enforced iff shared_tables = 0.
84 *
85 * Conversely, shared_tables is decreased when a vrf is de-associated
86 * from a table with exactly two associated vrfs.
87 */
88 u32 shared_tables;
89
90 bool strict_mode;
91};
92
93struct vrf_map_elem {
94 struct hlist_node hnode;
95 struct list_head vrf_list; /* VRFs registered to this table */
96
97 u32 table_id;
98 int users;
99 int ifindex;
100};
101
102static unsigned int vrf_net_id;
103
104/* per netns vrf data */
105struct netns_vrf {
106 /* protected by rtnl lock */
107 bool add_fib_rules;
108
109 struct vrf_map vmap;
110 struct ctl_table_header *ctl_hdr;
111};
112
113struct net_vrf {
114 struct rtable __rcu *rth;
115 struct rt6_info __rcu *rt6;
116#if IS_ENABLED(CONFIG_IPV6)
117 struct fib6_table *fib6_table;
118#endif
119 u32 tb_id;
120
121 struct list_head me_list; /* entry in vrf_map_elem */
122 int ifindex;
123};
124
125static void vrf_rx_stats(struct net_device *dev, int len)
126{
127 struct pcpu_dstats *dstats = this_cpu_ptr(dev->dstats);
128
129 u64_stats_update_begin(&dstats->syncp);
130 u64_stats_inc(&dstats->rx_packets);
131 u64_stats_add(&dstats->rx_bytes, len);
132 u64_stats_update_end(&dstats->syncp);
133}
134
135static void vrf_tx_error(struct net_device *vrf_dev, struct sk_buff *skb)
136{
137 vrf_dev->stats.tx_errors++;
138 kfree_skb(skb);
139}
140
141static struct vrf_map *netns_vrf_map(struct net *net)
142{
143 struct netns_vrf *nn_vrf = net_generic(net, vrf_net_id);
144
145 return &nn_vrf->vmap;
146}
147
148static struct vrf_map *netns_vrf_map_by_dev(struct net_device *dev)
149{
150 return netns_vrf_map(dev_net(dev));
151}
152
153static int vrf_map_elem_get_vrf_ifindex(struct vrf_map_elem *me)
154{
155 struct list_head *me_head = &me->vrf_list;
156 struct net_vrf *vrf;
157
158 if (list_empty(me_head))
159 return -ENODEV;
160
161 vrf = list_first_entry(me_head, struct net_vrf, me_list);
162
163 return vrf->ifindex;
164}
165
166static struct vrf_map_elem *vrf_map_elem_alloc(gfp_t flags)
167{
168 struct vrf_map_elem *me;
169
170 me = kmalloc(sizeof(*me), flags);
171 if (!me)
172 return NULL;
173
174 return me;
175}
176
177static void vrf_map_elem_free(struct vrf_map_elem *me)
178{
179 kfree(me);
180}
181
182static void vrf_map_elem_init(struct vrf_map_elem *me, int table_id,
183 int ifindex, int users)
184{
185 me->table_id = table_id;
186 me->ifindex = ifindex;
187 me->users = users;
188 INIT_LIST_HEAD(&me->vrf_list);
189}
190
191static struct vrf_map_elem *vrf_map_lookup_elem(struct vrf_map *vmap,
192 u32 table_id)
193{
194 struct vrf_map_elem *me;
195 u32 key;
196
197 key = jhash_1word(table_id, HASH_INITVAL);
198 hash_for_each_possible(vmap->ht, me, hnode, key) {
199 if (me->table_id == table_id)
200 return me;
201 }
202
203 return NULL;
204}
205
206static void vrf_map_add_elem(struct vrf_map *vmap, struct vrf_map_elem *me)
207{
208 u32 table_id = me->table_id;
209 u32 key;
210
211 key = jhash_1word(table_id, HASH_INITVAL);
212 hash_add(vmap->ht, &me->hnode, key);
213}
214
215static void vrf_map_del_elem(struct vrf_map_elem *me)
216{
217 hash_del(&me->hnode);
218}
219
220static void vrf_map_lock(struct vrf_map *vmap) __acquires(&vmap->vmap_lock)
221{
222 spin_lock(&vmap->vmap_lock);
223}
224
225static void vrf_map_unlock(struct vrf_map *vmap) __releases(&vmap->vmap_lock)
226{
227 spin_unlock(&vmap->vmap_lock);
228}
229
230/* called with rtnl lock held */
231static int
232vrf_map_register_dev(struct net_device *dev, struct netlink_ext_ack *extack)
233{
234 struct vrf_map *vmap = netns_vrf_map_by_dev(dev);
235 struct net_vrf *vrf = netdev_priv(dev);
236 struct vrf_map_elem *new_me, *me;
237 u32 table_id = vrf->tb_id;
238 bool free_new_me = false;
239 int users;
240 int res;
241
242 /* we pre-allocate elements used in the spin-locked section (so that we
243 * keep the spinlock as short as possible).
244 */
245 new_me = vrf_map_elem_alloc(GFP_KERNEL);
246 if (!new_me)
247 return -ENOMEM;
248
249 vrf_map_elem_init(new_me, table_id, dev->ifindex, 0);
250
251 vrf_map_lock(vmap);
252
253 me = vrf_map_lookup_elem(vmap, table_id);
254 if (!me) {
255 me = new_me;
256 vrf_map_add_elem(vmap, me);
257 goto link_vrf;
258 }
259
260 /* we already have an entry in the vrf_map, so it means there is (at
261 * least) a vrf registered on the specific table.
262 */
263 free_new_me = true;
264 if (vmap->strict_mode) {
265 /* vrfs cannot share the same table */
266 NL_SET_ERR_MSG(extack, "Table is used by another VRF");
267 res = -EBUSY;
268 goto unlock;
269 }
270
271link_vrf:
272 users = ++me->users;
273 if (users == 2)
274 ++vmap->shared_tables;
275
276 list_add(&vrf->me_list, &me->vrf_list);
277
278 res = 0;
279
280unlock:
281 vrf_map_unlock(vmap);
282
283 /* clean-up, if needed */
284 if (free_new_me)
285 vrf_map_elem_free(new_me);
286
287 return res;
288}
289
290/* called with rtnl lock held */
291static void vrf_map_unregister_dev(struct net_device *dev)
292{
293 struct vrf_map *vmap = netns_vrf_map_by_dev(dev);
294 struct net_vrf *vrf = netdev_priv(dev);
295 u32 table_id = vrf->tb_id;
296 struct vrf_map_elem *me;
297 int users;
298
299 vrf_map_lock(vmap);
300
301 me = vrf_map_lookup_elem(vmap, table_id);
302 if (!me)
303 goto unlock;
304
305 list_del(&vrf->me_list);
306
307 users = --me->users;
308 if (users == 1) {
309 --vmap->shared_tables;
310 } else if (users == 0) {
311 vrf_map_del_elem(me);
312
313 /* no one will refer to this element anymore */
314 vrf_map_elem_free(me);
315 }
316
317unlock:
318 vrf_map_unlock(vmap);
319}
320
321/* return the vrf device index associated with the table_id */
322static int vrf_ifindex_lookup_by_table_id(struct net *net, u32 table_id)
323{
324 struct vrf_map *vmap = netns_vrf_map(net);
325 struct vrf_map_elem *me;
326 int ifindex;
327
328 vrf_map_lock(vmap);
329
330 if (!vmap->strict_mode) {
331 ifindex = -EPERM;
332 goto unlock;
333 }
334
335 me = vrf_map_lookup_elem(vmap, table_id);
336 if (!me) {
337 ifindex = -ENODEV;
338 goto unlock;
339 }
340
341 ifindex = vrf_map_elem_get_vrf_ifindex(me);
342
343unlock:
344 vrf_map_unlock(vmap);
345
346 return ifindex;
347}
348
349/* by default VRF devices do not have a qdisc and are expected
350 * to be created with only a single queue.
351 */
352static bool qdisc_tx_is_default(const struct net_device *dev)
353{
354 struct netdev_queue *txq;
355 struct Qdisc *qdisc;
356
357 if (dev->num_tx_queues > 1)
358 return false;
359
360 txq = netdev_get_tx_queue(dev, 0);
361 qdisc = rcu_access_pointer(txq->qdisc);
362
363 return !qdisc->enqueue;
364}
365
366/* Local traffic destined to local address. Reinsert the packet to rx
367 * path, similar to loopback handling.
368 */
369static int vrf_local_xmit(struct sk_buff *skb, struct net_device *dev,
370 struct dst_entry *dst)
371{
372 int len = skb->len;
373
374 skb_orphan(skb);
375
376 skb_dst_set(skb, dst);
377
378 /* set pkt_type to avoid skb hitting packet taps twice -
379 * once on Tx and again in Rx processing
380 */
381 skb->pkt_type = PACKET_LOOPBACK;
382
383 skb->protocol = eth_type_trans(skb, dev);
384
385 if (likely(__netif_rx(skb) == NET_RX_SUCCESS)) {
386 vrf_rx_stats(dev, len);
387 } else {
388 struct pcpu_dstats *dstats = this_cpu_ptr(dev->dstats);
389
390 u64_stats_update_begin(&dstats->syncp);
391 u64_stats_inc(&dstats->rx_drops);
392 u64_stats_update_end(&dstats->syncp);
393 }
394
395 return NETDEV_TX_OK;
396}
397
398static void vrf_nf_set_untracked(struct sk_buff *skb)
399{
400 if (skb_get_nfct(skb) == 0)
401 nf_ct_set(skb, NULL, IP_CT_UNTRACKED);
402}
403
404static void vrf_nf_reset_ct(struct sk_buff *skb)
405{
406 if (skb_get_nfct(skb) == IP_CT_UNTRACKED)
407 nf_reset_ct(skb);
408}
409
410#if IS_ENABLED(CONFIG_IPV6)
411static int vrf_ip6_local_out(struct net *net, struct sock *sk,
412 struct sk_buff *skb)
413{
414 int err;
415
416 vrf_nf_reset_ct(skb);
417
418 err = nf_hook(NFPROTO_IPV6, NF_INET_LOCAL_OUT, net,
419 sk, skb, NULL, skb_dst(skb)->dev, dst_output);
420
421 if (likely(err == 1))
422 err = dst_output(net, sk, skb);
423
424 return err;
425}
426
427static netdev_tx_t vrf_process_v6_outbound(struct sk_buff *skb,
428 struct net_device *dev)
429{
430 const struct ipv6hdr *iph;
431 struct net *net = dev_net(skb->dev);
432 struct flowi6 fl6;
433 int ret = NET_XMIT_DROP;
434 struct dst_entry *dst;
435 struct dst_entry *dst_null = &net->ipv6.ip6_null_entry->dst;
436
437 if (!pskb_may_pull(skb, ETH_HLEN + sizeof(struct ipv6hdr)))
438 goto err;
439
440 iph = ipv6_hdr(skb);
441
442 memset(&fl6, 0, sizeof(fl6));
443 /* needed to match OIF rule */
444 fl6.flowi6_l3mdev = dev->ifindex;
445 fl6.flowi6_iif = LOOPBACK_IFINDEX;
446 fl6.daddr = iph->daddr;
447 fl6.saddr = iph->saddr;
448 fl6.flowlabel = ip6_flowinfo(iph);
449 fl6.flowi6_mark = skb->mark;
450 fl6.flowi6_proto = iph->nexthdr;
451
452 dst = ip6_dst_lookup_flow(net, NULL, &fl6, NULL);
453 if (IS_ERR(dst) || dst == dst_null)
454 goto err;
455
456 skb_dst_drop(skb);
457
458 /* if dst.dev is the VRF device again this is locally originated traffic
459 * destined to a local address. Short circuit to Rx path.
460 */
461 if (dst->dev == dev)
462 return vrf_local_xmit(skb, dev, dst);
463
464 skb_dst_set(skb, dst);
465
466 /* strip the ethernet header added for pass through VRF device */
467 __skb_pull(skb, skb_network_offset(skb));
468
469 memset(IP6CB(skb), 0, sizeof(*IP6CB(skb)));
470 ret = vrf_ip6_local_out(net, skb->sk, skb);
471 if (unlikely(net_xmit_eval(ret)))
472 dev->stats.tx_errors++;
473 else
474 ret = NET_XMIT_SUCCESS;
475
476 return ret;
477err:
478 vrf_tx_error(dev, skb);
479 return NET_XMIT_DROP;
480}
481#else
482static netdev_tx_t vrf_process_v6_outbound(struct sk_buff *skb,
483 struct net_device *dev)
484{
485 vrf_tx_error(dev, skb);
486 return NET_XMIT_DROP;
487}
488#endif
489
490/* based on ip_local_out; can't use it b/c the dst is switched pointing to us */
491static int vrf_ip_local_out(struct net *net, struct sock *sk,
492 struct sk_buff *skb)
493{
494 int err;
495
496 vrf_nf_reset_ct(skb);
497
498 err = nf_hook(NFPROTO_IPV4, NF_INET_LOCAL_OUT, net, sk,
499 skb, NULL, skb_dst(skb)->dev, dst_output);
500 if (likely(err == 1))
501 err = dst_output(net, sk, skb);
502
503 return err;
504}
505
506static netdev_tx_t vrf_process_v4_outbound(struct sk_buff *skb,
507 struct net_device *vrf_dev)
508{
509 struct iphdr *ip4h;
510 int ret = NET_XMIT_DROP;
511 struct flowi4 fl4;
512 struct net *net = dev_net(vrf_dev);
513 struct rtable *rt;
514
515 if (!pskb_may_pull(skb, ETH_HLEN + sizeof(struct iphdr)))
516 goto err;
517
518 ip4h = ip_hdr(skb);
519
520 memset(&fl4, 0, sizeof(fl4));
521 /* needed to match OIF rule */
522 fl4.flowi4_l3mdev = vrf_dev->ifindex;
523 fl4.flowi4_iif = LOOPBACK_IFINDEX;
524 fl4.flowi4_tos = inet_dscp_to_dsfield(ip4h_dscp(ip4h));
525 fl4.flowi4_flags = FLOWI_FLAG_ANYSRC;
526 fl4.flowi4_proto = ip4h->protocol;
527 fl4.daddr = ip4h->daddr;
528 fl4.saddr = ip4h->saddr;
529
530 rt = ip_route_output_flow(net, &fl4, NULL);
531 if (IS_ERR(rt))
532 goto err;
533
534 skb_dst_drop(skb);
535
536 /* if dst.dev is the VRF device again this is locally originated traffic
537 * destined to a local address. Short circuit to Rx path.
538 */
539 if (rt->dst.dev == vrf_dev)
540 return vrf_local_xmit(skb, vrf_dev, &rt->dst);
541
542 skb_dst_set(skb, &rt->dst);
543
544 /* strip the ethernet header added for pass through VRF device */
545 __skb_pull(skb, skb_network_offset(skb));
546
547 if (!ip4h->saddr) {
548 ip4h->saddr = inet_select_addr(skb_dst(skb)->dev, 0,
549 RT_SCOPE_LINK);
550 }
551
552 memset(IPCB(skb), 0, sizeof(*IPCB(skb)));
553 ret = vrf_ip_local_out(dev_net(skb_dst(skb)->dev), skb->sk, skb);
554 if (unlikely(net_xmit_eval(ret)))
555 vrf_dev->stats.tx_errors++;
556 else
557 ret = NET_XMIT_SUCCESS;
558
559out:
560 return ret;
561err:
562 vrf_tx_error(vrf_dev, skb);
563 goto out;
564}
565
566static netdev_tx_t is_ip_tx_frame(struct sk_buff *skb, struct net_device *dev)
567{
568 switch (skb->protocol) {
569 case htons(ETH_P_IP):
570 return vrf_process_v4_outbound(skb, dev);
571 case htons(ETH_P_IPV6):
572 return vrf_process_v6_outbound(skb, dev);
573 default:
574 vrf_tx_error(dev, skb);
575 return NET_XMIT_DROP;
576 }
577}
578
579static netdev_tx_t vrf_xmit(struct sk_buff *skb, struct net_device *dev)
580{
581 struct pcpu_dstats *dstats = this_cpu_ptr(dev->dstats);
582
583 int len = skb->len;
584 netdev_tx_t ret = is_ip_tx_frame(skb, dev);
585
586 u64_stats_update_begin(&dstats->syncp);
587 if (likely(ret == NET_XMIT_SUCCESS || ret == NET_XMIT_CN)) {
588
589 u64_stats_inc(&dstats->tx_packets);
590 u64_stats_add(&dstats->tx_bytes, len);
591 } else {
592 u64_stats_inc(&dstats->tx_drops);
593 }
594 u64_stats_update_end(&dstats->syncp);
595
596 return ret;
597}
598
599static void vrf_finish_direct(struct sk_buff *skb)
600{
601 struct net_device *vrf_dev = skb->dev;
602
603 if (!list_empty(&vrf_dev->ptype_all) &&
604 likely(skb_headroom(skb) >= ETH_HLEN)) {
605 struct ethhdr *eth = skb_push(skb, ETH_HLEN);
606
607 ether_addr_copy(eth->h_source, vrf_dev->dev_addr);
608 eth_zero_addr(eth->h_dest);
609 eth->h_proto = skb->protocol;
610
611 rcu_read_lock_bh();
612 dev_queue_xmit_nit(skb, vrf_dev);
613 rcu_read_unlock_bh();
614
615 skb_pull(skb, ETH_HLEN);
616 }
617
618 vrf_nf_reset_ct(skb);
619}
620
621#if IS_ENABLED(CONFIG_IPV6)
622/* modelled after ip6_finish_output2 */
623static int vrf_finish_output6(struct net *net, struct sock *sk,
624 struct sk_buff *skb)
625{
626 struct dst_entry *dst = skb_dst(skb);
627 struct net_device *dev = dst->dev;
628 const struct in6_addr *nexthop;
629 struct neighbour *neigh;
630 int ret;
631
632 vrf_nf_reset_ct(skb);
633
634 skb->protocol = htons(ETH_P_IPV6);
635 skb->dev = dev;
636
637 rcu_read_lock();
638 nexthop = rt6_nexthop(dst_rt6_info(dst), &ipv6_hdr(skb)->daddr);
639 neigh = __ipv6_neigh_lookup_noref(dst->dev, nexthop);
640 if (unlikely(!neigh))
641 neigh = __neigh_create(&nd_tbl, nexthop, dst->dev, false);
642 if (!IS_ERR(neigh)) {
643 sock_confirm_neigh(skb, neigh);
644 ret = neigh_output(neigh, skb, false);
645 rcu_read_unlock();
646 return ret;
647 }
648 rcu_read_unlock();
649
650 IP6_INC_STATS(dev_net(dst->dev),
651 ip6_dst_idev(dst), IPSTATS_MIB_OUTNOROUTES);
652 kfree_skb(skb);
653 return -EINVAL;
654}
655
656/* modelled after ip6_output */
657static int vrf_output6(struct net *net, struct sock *sk, struct sk_buff *skb)
658{
659 return NF_HOOK_COND(NFPROTO_IPV6, NF_INET_POST_ROUTING,
660 net, sk, skb, NULL, skb_dst(skb)->dev,
661 vrf_finish_output6,
662 !(IP6CB(skb)->flags & IP6SKB_REROUTED));
663}
664
665/* set dst on skb to send packet to us via dev_xmit path. Allows
666 * packet to go through device based features such as qdisc, netfilter
667 * hooks and packet sockets with skb->dev set to vrf device.
668 */
669static struct sk_buff *vrf_ip6_out_redirect(struct net_device *vrf_dev,
670 struct sk_buff *skb)
671{
672 struct net_vrf *vrf = netdev_priv(vrf_dev);
673 struct dst_entry *dst = NULL;
674 struct rt6_info *rt6;
675
676 rcu_read_lock();
677
678 rt6 = rcu_dereference(vrf->rt6);
679 if (likely(rt6)) {
680 dst = &rt6->dst;
681 dst_hold(dst);
682 }
683
684 rcu_read_unlock();
685
686 if (unlikely(!dst)) {
687 vrf_tx_error(vrf_dev, skb);
688 return NULL;
689 }
690
691 skb_dst_drop(skb);
692 skb_dst_set(skb, dst);
693
694 return skb;
695}
696
697static int vrf_output6_direct_finish(struct net *net, struct sock *sk,
698 struct sk_buff *skb)
699{
700 vrf_finish_direct(skb);
701
702 return vrf_ip6_local_out(net, sk, skb);
703}
704
705static int vrf_output6_direct(struct net *net, struct sock *sk,
706 struct sk_buff *skb)
707{
708 int err = 1;
709
710 skb->protocol = htons(ETH_P_IPV6);
711
712 if (!(IPCB(skb)->flags & IPSKB_REROUTED))
713 err = nf_hook(NFPROTO_IPV6, NF_INET_POST_ROUTING, net, sk, skb,
714 NULL, skb->dev, vrf_output6_direct_finish);
715
716 if (likely(err == 1))
717 vrf_finish_direct(skb);
718
719 return err;
720}
721
722static int vrf_ip6_out_direct_finish(struct net *net, struct sock *sk,
723 struct sk_buff *skb)
724{
725 int err;
726
727 err = vrf_output6_direct(net, sk, skb);
728 if (likely(err == 1))
729 err = vrf_ip6_local_out(net, sk, skb);
730
731 return err;
732}
733
734static struct sk_buff *vrf_ip6_out_direct(struct net_device *vrf_dev,
735 struct sock *sk,
736 struct sk_buff *skb)
737{
738 struct net *net = dev_net(vrf_dev);
739 int err;
740
741 skb->dev = vrf_dev;
742
743 err = nf_hook(NFPROTO_IPV6, NF_INET_LOCAL_OUT, net, sk,
744 skb, NULL, vrf_dev, vrf_ip6_out_direct_finish);
745
746 if (likely(err == 1))
747 err = vrf_output6_direct(net, sk, skb);
748
749 if (likely(err == 1))
750 return skb;
751
752 return NULL;
753}
754
755static struct sk_buff *vrf_ip6_out(struct net_device *vrf_dev,
756 struct sock *sk,
757 struct sk_buff *skb)
758{
759 /* don't divert link scope packets */
760 if (rt6_need_strict(&ipv6_hdr(skb)->daddr))
761 return skb;
762
763 vrf_nf_set_untracked(skb);
764
765 if (qdisc_tx_is_default(vrf_dev) ||
766 IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED)
767 return vrf_ip6_out_direct(vrf_dev, sk, skb);
768
769 return vrf_ip6_out_redirect(vrf_dev, skb);
770}
771
772/* holding rtnl */
773static void vrf_rt6_release(struct net_device *dev, struct net_vrf *vrf)
774{
775 struct rt6_info *rt6 = rtnl_dereference(vrf->rt6);
776 struct net *net = dev_net(dev);
777 struct dst_entry *dst;
778
779 RCU_INIT_POINTER(vrf->rt6, NULL);
780 synchronize_rcu();
781
782 /* move dev in dst's to loopback so this VRF device can be deleted
783 * - based on dst_ifdown
784 */
785 if (rt6) {
786 dst = &rt6->dst;
787 netdev_ref_replace(dst->dev, net->loopback_dev,
788 &dst->dev_tracker, GFP_KERNEL);
789 dst->dev = net->loopback_dev;
790 dst_release(dst);
791 }
792}
793
794static int vrf_rt6_create(struct net_device *dev)
795{
796 int flags = DST_NOPOLICY | DST_NOXFRM;
797 struct net_vrf *vrf = netdev_priv(dev);
798 struct net *net = dev_net(dev);
799 struct rt6_info *rt6;
800 int rc = -ENOMEM;
801
802 /* IPv6 can be CONFIG enabled and then disabled runtime */
803 if (!ipv6_mod_enabled())
804 return 0;
805
806 vrf->fib6_table = fib6_new_table(net, vrf->tb_id);
807 if (!vrf->fib6_table)
808 goto out;
809
810 /* create a dst for routing packets out a VRF device */
811 rt6 = ip6_dst_alloc(net, dev, flags);
812 if (!rt6)
813 goto out;
814
815 rt6->dst.output = vrf_output6;
816
817 rcu_assign_pointer(vrf->rt6, rt6);
818
819 rc = 0;
820out:
821 return rc;
822}
823#else
824static struct sk_buff *vrf_ip6_out(struct net_device *vrf_dev,
825 struct sock *sk,
826 struct sk_buff *skb)
827{
828 return skb;
829}
830
831static void vrf_rt6_release(struct net_device *dev, struct net_vrf *vrf)
832{
833}
834
835static int vrf_rt6_create(struct net_device *dev)
836{
837 return 0;
838}
839#endif
840
841/* modelled after ip_finish_output2 */
842static int vrf_finish_output(struct net *net, struct sock *sk, struct sk_buff *skb)
843{
844 struct dst_entry *dst = skb_dst(skb);
845 struct rtable *rt = dst_rtable(dst);
846 struct net_device *dev = dst->dev;
847 unsigned int hh_len = LL_RESERVED_SPACE(dev);
848 struct neighbour *neigh;
849 bool is_v6gw = false;
850
851 vrf_nf_reset_ct(skb);
852
853 /* Be paranoid, rather than too clever. */
854 if (unlikely(skb_headroom(skb) < hh_len && dev->header_ops)) {
855 skb = skb_expand_head(skb, hh_len);
856 if (!skb) {
857 dev->stats.tx_errors++;
858 return -ENOMEM;
859 }
860 }
861
862 rcu_read_lock();
863
864 neigh = ip_neigh_for_gw(rt, skb, &is_v6gw);
865 if (!IS_ERR(neigh)) {
866 int ret;
867
868 sock_confirm_neigh(skb, neigh);
869 /* if crossing protocols, can not use the cached header */
870 ret = neigh_output(neigh, skb, is_v6gw);
871 rcu_read_unlock();
872 return ret;
873 }
874
875 rcu_read_unlock();
876 vrf_tx_error(skb->dev, skb);
877 return -EINVAL;
878}
879
880static int vrf_output(struct net *net, struct sock *sk, struct sk_buff *skb)
881{
882 struct net_device *dev = skb_dst(skb)->dev;
883
884 IP_UPD_PO_STATS(net, IPSTATS_MIB_OUT, skb->len);
885
886 skb->dev = dev;
887 skb->protocol = htons(ETH_P_IP);
888
889 return NF_HOOK_COND(NFPROTO_IPV4, NF_INET_POST_ROUTING,
890 net, sk, skb, NULL, dev,
891 vrf_finish_output,
892 !(IPCB(skb)->flags & IPSKB_REROUTED));
893}
894
895/* set dst on skb to send packet to us via dev_xmit path. Allows
896 * packet to go through device based features such as qdisc, netfilter
897 * hooks and packet sockets with skb->dev set to vrf device.
898 */
899static struct sk_buff *vrf_ip_out_redirect(struct net_device *vrf_dev,
900 struct sk_buff *skb)
901{
902 struct net_vrf *vrf = netdev_priv(vrf_dev);
903 struct dst_entry *dst = NULL;
904 struct rtable *rth;
905
906 rcu_read_lock();
907
908 rth = rcu_dereference(vrf->rth);
909 if (likely(rth)) {
910 dst = &rth->dst;
911 dst_hold(dst);
912 }
913
914 rcu_read_unlock();
915
916 if (unlikely(!dst)) {
917 vrf_tx_error(vrf_dev, skb);
918 return NULL;
919 }
920
921 skb_dst_drop(skb);
922 skb_dst_set(skb, dst);
923
924 return skb;
925}
926
927static int vrf_output_direct_finish(struct net *net, struct sock *sk,
928 struct sk_buff *skb)
929{
930 vrf_finish_direct(skb);
931
932 return vrf_ip_local_out(net, sk, skb);
933}
934
935static int vrf_output_direct(struct net *net, struct sock *sk,
936 struct sk_buff *skb)
937{
938 int err = 1;
939
940 skb->protocol = htons(ETH_P_IP);
941
942 if (!(IPCB(skb)->flags & IPSKB_REROUTED))
943 err = nf_hook(NFPROTO_IPV4, NF_INET_POST_ROUTING, net, sk, skb,
944 NULL, skb->dev, vrf_output_direct_finish);
945
946 if (likely(err == 1))
947 vrf_finish_direct(skb);
948
949 return err;
950}
951
952static int vrf_ip_out_direct_finish(struct net *net, struct sock *sk,
953 struct sk_buff *skb)
954{
955 int err;
956
957 err = vrf_output_direct(net, sk, skb);
958 if (likely(err == 1))
959 err = vrf_ip_local_out(net, sk, skb);
960
961 return err;
962}
963
964static struct sk_buff *vrf_ip_out_direct(struct net_device *vrf_dev,
965 struct sock *sk,
966 struct sk_buff *skb)
967{
968 struct net *net = dev_net(vrf_dev);
969 int err;
970
971 skb->dev = vrf_dev;
972
973 err = nf_hook(NFPROTO_IPV4, NF_INET_LOCAL_OUT, net, sk,
974 skb, NULL, vrf_dev, vrf_ip_out_direct_finish);
975
976 if (likely(err == 1))
977 err = vrf_output_direct(net, sk, skb);
978
979 if (likely(err == 1))
980 return skb;
981
982 return NULL;
983}
984
985static struct sk_buff *vrf_ip_out(struct net_device *vrf_dev,
986 struct sock *sk,
987 struct sk_buff *skb)
988{
989 /* don't divert multicast or local broadcast */
990 if (ipv4_is_multicast(ip_hdr(skb)->daddr) ||
991 ipv4_is_lbcast(ip_hdr(skb)->daddr))
992 return skb;
993
994 vrf_nf_set_untracked(skb);
995
996 if (qdisc_tx_is_default(vrf_dev) ||
997 IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED)
998 return vrf_ip_out_direct(vrf_dev, sk, skb);
999
1000 return vrf_ip_out_redirect(vrf_dev, skb);
1001}
1002
1003/* called with rcu lock held */
1004static struct sk_buff *vrf_l3_out(struct net_device *vrf_dev,
1005 struct sock *sk,
1006 struct sk_buff *skb,
1007 u16 proto)
1008{
1009 switch (proto) {
1010 case AF_INET:
1011 return vrf_ip_out(vrf_dev, sk, skb);
1012 case AF_INET6:
1013 return vrf_ip6_out(vrf_dev, sk, skb);
1014 }
1015
1016 return skb;
1017}
1018
1019/* holding rtnl */
1020static void vrf_rtable_release(struct net_device *dev, struct net_vrf *vrf)
1021{
1022 struct rtable *rth = rtnl_dereference(vrf->rth);
1023 struct net *net = dev_net(dev);
1024 struct dst_entry *dst;
1025
1026 RCU_INIT_POINTER(vrf->rth, NULL);
1027 synchronize_rcu();
1028
1029 /* move dev in dst's to loopback so this VRF device can be deleted
1030 * - based on dst_ifdown
1031 */
1032 if (rth) {
1033 dst = &rth->dst;
1034 netdev_ref_replace(dst->dev, net->loopback_dev,
1035 &dst->dev_tracker, GFP_KERNEL);
1036 dst->dev = net->loopback_dev;
1037 dst_release(dst);
1038 }
1039}
1040
1041static int vrf_rtable_create(struct net_device *dev)
1042{
1043 struct net_vrf *vrf = netdev_priv(dev);
1044 struct rtable *rth;
1045
1046 if (!fib_new_table(dev_net(dev), vrf->tb_id))
1047 return -ENOMEM;
1048
1049 /* create a dst for routing packets out through a VRF device */
1050 rth = rt_dst_alloc(dev, 0, RTN_UNICAST, 1);
1051 if (!rth)
1052 return -ENOMEM;
1053
1054 rth->dst.output = vrf_output;
1055
1056 rcu_assign_pointer(vrf->rth, rth);
1057
1058 return 0;
1059}
1060
1061/**************************** device handling ********************/
1062
1063/* cycle interface to flush neighbor cache and move routes across tables */
1064static void cycle_netdev(struct net_device *dev,
1065 struct netlink_ext_ack *extack)
1066{
1067 unsigned int flags = dev->flags;
1068 int ret;
1069
1070 if (!netif_running(dev))
1071 return;
1072
1073 ret = dev_change_flags(dev, flags & ~IFF_UP, extack);
1074 if (ret >= 0)
1075 ret = dev_change_flags(dev, flags, extack);
1076
1077 if (ret < 0) {
1078 netdev_err(dev,
1079 "Failed to cycle device %s; route tables might be wrong!\n",
1080 dev->name);
1081 }
1082}
1083
1084static int do_vrf_add_slave(struct net_device *dev, struct net_device *port_dev,
1085 struct netlink_ext_ack *extack)
1086{
1087 int ret;
1088
1089 /* do not allow loopback device to be enslaved to a VRF.
1090 * The vrf device acts as the loopback for the vrf.
1091 */
1092 if (port_dev == dev_net(dev)->loopback_dev) {
1093 NL_SET_ERR_MSG(extack,
1094 "Can not enslave loopback device to a VRF");
1095 return -EOPNOTSUPP;
1096 }
1097
1098 port_dev->priv_flags |= IFF_L3MDEV_SLAVE;
1099 ret = netdev_master_upper_dev_link(port_dev, dev, NULL, NULL, extack);
1100 if (ret < 0)
1101 goto err;
1102
1103 cycle_netdev(port_dev, extack);
1104
1105 return 0;
1106
1107err:
1108 port_dev->priv_flags &= ~IFF_L3MDEV_SLAVE;
1109 return ret;
1110}
1111
1112static int vrf_add_slave(struct net_device *dev, struct net_device *port_dev,
1113 struct netlink_ext_ack *extack)
1114{
1115 if (netif_is_l3_master(port_dev)) {
1116 NL_SET_ERR_MSG(extack,
1117 "Can not enslave an L3 master device to a VRF");
1118 return -EINVAL;
1119 }
1120
1121 if (netif_is_l3_slave(port_dev))
1122 return -EINVAL;
1123
1124 return do_vrf_add_slave(dev, port_dev, extack);
1125}
1126
1127/* inverse of do_vrf_add_slave */
1128static int do_vrf_del_slave(struct net_device *dev, struct net_device *port_dev)
1129{
1130 netdev_upper_dev_unlink(port_dev, dev);
1131 port_dev->priv_flags &= ~IFF_L3MDEV_SLAVE;
1132
1133 cycle_netdev(port_dev, NULL);
1134
1135 return 0;
1136}
1137
1138static int vrf_del_slave(struct net_device *dev, struct net_device *port_dev)
1139{
1140 return do_vrf_del_slave(dev, port_dev);
1141}
1142
1143static void vrf_dev_uninit(struct net_device *dev)
1144{
1145 struct net_vrf *vrf = netdev_priv(dev);
1146
1147 vrf_rtable_release(dev, vrf);
1148 vrf_rt6_release(dev, vrf);
1149}
1150
1151static int vrf_dev_init(struct net_device *dev)
1152{
1153 struct net_vrf *vrf = netdev_priv(dev);
1154
1155 /* create the default dst which points back to us */
1156 if (vrf_rtable_create(dev) != 0)
1157 goto out_nomem;
1158
1159 if (vrf_rt6_create(dev) != 0)
1160 goto out_rth;
1161
1162 dev->flags = IFF_MASTER | IFF_NOARP;
1163
1164 /* similarly, oper state is irrelevant; set to up to avoid confusion */
1165 dev->operstate = IF_OPER_UP;
1166 netdev_lockdep_set_classes(dev);
1167 return 0;
1168
1169out_rth:
1170 vrf_rtable_release(dev, vrf);
1171out_nomem:
1172 return -ENOMEM;
1173}
1174
1175static const struct net_device_ops vrf_netdev_ops = {
1176 .ndo_init = vrf_dev_init,
1177 .ndo_uninit = vrf_dev_uninit,
1178 .ndo_start_xmit = vrf_xmit,
1179 .ndo_set_mac_address = eth_mac_addr,
1180 .ndo_add_slave = vrf_add_slave,
1181 .ndo_del_slave = vrf_del_slave,
1182};
1183
1184static u32 vrf_fib_table(const struct net_device *dev)
1185{
1186 struct net_vrf *vrf = netdev_priv(dev);
1187
1188 return vrf->tb_id;
1189}
1190
1191static int vrf_rcv_finish(struct net *net, struct sock *sk, struct sk_buff *skb)
1192{
1193 kfree_skb(skb);
1194 return 0;
1195}
1196
1197static struct sk_buff *vrf_rcv_nfhook(u8 pf, unsigned int hook,
1198 struct sk_buff *skb,
1199 struct net_device *dev)
1200{
1201 struct net *net = dev_net(dev);
1202
1203 if (nf_hook(pf, hook, net, NULL, skb, dev, NULL, vrf_rcv_finish) != 1)
1204 skb = NULL; /* kfree_skb(skb) handled by nf code */
1205
1206 return skb;
1207}
1208
1209static int vrf_prepare_mac_header(struct sk_buff *skb,
1210 struct net_device *vrf_dev, u16 proto)
1211{
1212 struct ethhdr *eth;
1213 int err;
1214
1215 /* in general, we do not know if there is enough space in the head of
1216 * the packet for hosting the mac header.
1217 */
1218 err = skb_cow_head(skb, LL_RESERVED_SPACE(vrf_dev));
1219 if (unlikely(err))
1220 /* no space in the skb head */
1221 return -ENOBUFS;
1222
1223 __skb_push(skb, ETH_HLEN);
1224 eth = (struct ethhdr *)skb->data;
1225
1226 skb_reset_mac_header(skb);
1227 skb_reset_mac_len(skb);
1228
1229 /* we set the ethernet destination and the source addresses to the
1230 * address of the VRF device.
1231 */
1232 ether_addr_copy(eth->h_dest, vrf_dev->dev_addr);
1233 ether_addr_copy(eth->h_source, vrf_dev->dev_addr);
1234 eth->h_proto = htons(proto);
1235
1236 /* the destination address of the Ethernet frame corresponds to the
1237 * address set on the VRF interface; therefore, the packet is intended
1238 * to be processed locally.
1239 */
1240 skb->protocol = eth->h_proto;
1241 skb->pkt_type = PACKET_HOST;
1242
1243 skb_postpush_rcsum(skb, skb->data, ETH_HLEN);
1244
1245 skb_pull_inline(skb, ETH_HLEN);
1246
1247 return 0;
1248}
1249
1250/* prepare and add the mac header to the packet if it was not set previously.
1251 * In this way, packet sniffers such as tcpdump can parse the packet correctly.
1252 * If the mac header was already set, the original mac header is left
1253 * untouched and the function returns immediately.
1254 */
1255static int vrf_add_mac_header_if_unset(struct sk_buff *skb,
1256 struct net_device *vrf_dev,
1257 u16 proto, struct net_device *orig_dev)
1258{
1259 if (skb_mac_header_was_set(skb) && dev_has_header(orig_dev))
1260 return 0;
1261
1262 return vrf_prepare_mac_header(skb, vrf_dev, proto);
1263}
1264
1265#if IS_ENABLED(CONFIG_IPV6)
1266/* neighbor handling is done with actual device; do not want
1267 * to flip skb->dev for those ndisc packets. This really fails
1268 * for multiple next protocols (e.g., NEXTHDR_HOP). But it is
1269 * a start.
1270 */
1271static bool ipv6_ndisc_frame(const struct sk_buff *skb)
1272{
1273 const struct ipv6hdr *iph = ipv6_hdr(skb);
1274 bool rc = false;
1275
1276 if (iph->nexthdr == NEXTHDR_ICMP) {
1277 const struct icmp6hdr *icmph;
1278 struct icmp6hdr _icmph;
1279
1280 icmph = skb_header_pointer(skb, sizeof(*iph),
1281 sizeof(_icmph), &_icmph);
1282 if (!icmph)
1283 goto out;
1284
1285 switch (icmph->icmp6_type) {
1286 case NDISC_ROUTER_SOLICITATION:
1287 case NDISC_ROUTER_ADVERTISEMENT:
1288 case NDISC_NEIGHBOUR_SOLICITATION:
1289 case NDISC_NEIGHBOUR_ADVERTISEMENT:
1290 case NDISC_REDIRECT:
1291 rc = true;
1292 break;
1293 }
1294 }
1295
1296out:
1297 return rc;
1298}
1299
1300static struct rt6_info *vrf_ip6_route_lookup(struct net *net,
1301 const struct net_device *dev,
1302 struct flowi6 *fl6,
1303 int ifindex,
1304 const struct sk_buff *skb,
1305 int flags)
1306{
1307 struct net_vrf *vrf = netdev_priv(dev);
1308
1309 return ip6_pol_route(net, vrf->fib6_table, ifindex, fl6, skb, flags);
1310}
1311
1312static void vrf_ip6_input_dst(struct sk_buff *skb, struct net_device *vrf_dev,
1313 int ifindex)
1314{
1315 const struct ipv6hdr *iph = ipv6_hdr(skb);
1316 struct flowi6 fl6 = {
1317 .flowi6_iif = ifindex,
1318 .flowi6_mark = skb->mark,
1319 .flowi6_proto = iph->nexthdr,
1320 .daddr = iph->daddr,
1321 .saddr = iph->saddr,
1322 .flowlabel = ip6_flowinfo(iph),
1323 };
1324 struct net *net = dev_net(vrf_dev);
1325 struct rt6_info *rt6;
1326
1327 rt6 = vrf_ip6_route_lookup(net, vrf_dev, &fl6, ifindex, skb,
1328 RT6_LOOKUP_F_HAS_SADDR | RT6_LOOKUP_F_IFACE);
1329 if (unlikely(!rt6))
1330 return;
1331
1332 if (unlikely(&rt6->dst == &net->ipv6.ip6_null_entry->dst))
1333 return;
1334
1335 skb_dst_set(skb, &rt6->dst);
1336}
1337
1338static struct sk_buff *vrf_ip6_rcv(struct net_device *vrf_dev,
1339 struct sk_buff *skb)
1340{
1341 int orig_iif = skb->skb_iif;
1342 bool need_strict = rt6_need_strict(&ipv6_hdr(skb)->daddr);
1343 bool is_ndisc = ipv6_ndisc_frame(skb);
1344
1345 /* loopback, multicast & non-ND link-local traffic; do not push through
1346 * packet taps again. Reset pkt_type for upper layers to process skb.
1347 * For non-loopback strict packets, determine the dst using the original
1348 * ifindex.
1349 */
1350 if (skb->pkt_type == PACKET_LOOPBACK || (need_strict && !is_ndisc)) {
1351 skb->dev = vrf_dev;
1352 skb->skb_iif = vrf_dev->ifindex;
1353 IP6CB(skb)->flags |= IP6SKB_L3SLAVE;
1354
1355 if (skb->pkt_type == PACKET_LOOPBACK)
1356 skb->pkt_type = PACKET_HOST;
1357 else
1358 vrf_ip6_input_dst(skb, vrf_dev, orig_iif);
1359
1360 goto out;
1361 }
1362
1363 /* if packet is NDISC then keep the ingress interface */
1364 if (!is_ndisc) {
1365 struct net_device *orig_dev = skb->dev;
1366
1367 vrf_rx_stats(vrf_dev, skb->len);
1368 skb->dev = vrf_dev;
1369 skb->skb_iif = vrf_dev->ifindex;
1370
1371 if (!list_empty(&vrf_dev->ptype_all)) {
1372 int err;
1373
1374 err = vrf_add_mac_header_if_unset(skb, vrf_dev,
1375 ETH_P_IPV6,
1376 orig_dev);
1377 if (likely(!err)) {
1378 skb_push(skb, skb->mac_len);
1379 dev_queue_xmit_nit(skb, vrf_dev);
1380 skb_pull(skb, skb->mac_len);
1381 }
1382 }
1383
1384 IP6CB(skb)->flags |= IP6SKB_L3SLAVE;
1385 }
1386
1387 if (need_strict)
1388 vrf_ip6_input_dst(skb, vrf_dev, orig_iif);
1389
1390 skb = vrf_rcv_nfhook(NFPROTO_IPV6, NF_INET_PRE_ROUTING, skb, vrf_dev);
1391out:
1392 return skb;
1393}
1394
1395#else
1396static struct sk_buff *vrf_ip6_rcv(struct net_device *vrf_dev,
1397 struct sk_buff *skb)
1398{
1399 return skb;
1400}
1401#endif
1402
1403static struct sk_buff *vrf_ip_rcv(struct net_device *vrf_dev,
1404 struct sk_buff *skb)
1405{
1406 struct net_device *orig_dev = skb->dev;
1407
1408 skb->dev = vrf_dev;
1409 skb->skb_iif = vrf_dev->ifindex;
1410 IPCB(skb)->flags |= IPSKB_L3SLAVE;
1411
1412 if (ipv4_is_multicast(ip_hdr(skb)->daddr))
1413 goto out;
1414
1415 /* loopback traffic; do not push through packet taps again.
1416 * Reset pkt_type for upper layers to process skb
1417 */
1418 if (skb->pkt_type == PACKET_LOOPBACK) {
1419 skb->pkt_type = PACKET_HOST;
1420 goto out;
1421 }
1422
1423 vrf_rx_stats(vrf_dev, skb->len);
1424
1425 if (!list_empty(&vrf_dev->ptype_all)) {
1426 int err;
1427
1428 err = vrf_add_mac_header_if_unset(skb, vrf_dev, ETH_P_IP,
1429 orig_dev);
1430 if (likely(!err)) {
1431 skb_push(skb, skb->mac_len);
1432 dev_queue_xmit_nit(skb, vrf_dev);
1433 skb_pull(skb, skb->mac_len);
1434 }
1435 }
1436
1437 skb = vrf_rcv_nfhook(NFPROTO_IPV4, NF_INET_PRE_ROUTING, skb, vrf_dev);
1438out:
1439 return skb;
1440}
1441
1442/* called with rcu lock held */
1443static struct sk_buff *vrf_l3_rcv(struct net_device *vrf_dev,
1444 struct sk_buff *skb,
1445 u16 proto)
1446{
1447 switch (proto) {
1448 case AF_INET:
1449 return vrf_ip_rcv(vrf_dev, skb);
1450 case AF_INET6:
1451 return vrf_ip6_rcv(vrf_dev, skb);
1452 }
1453
1454 return skb;
1455}
1456
1457#if IS_ENABLED(CONFIG_IPV6)
1458/* send to link-local or multicast address via interface enslaved to
1459 * VRF device. Force lookup to VRF table without changing flow struct
1460 * Note: Caller to this function must hold rcu_read_lock() and no refcnt
1461 * is taken on the dst by this function.
1462 */
1463static struct dst_entry *vrf_link_scope_lookup(const struct net_device *dev,
1464 struct flowi6 *fl6)
1465{
1466 struct net *net = dev_net(dev);
1467 int flags = RT6_LOOKUP_F_IFACE | RT6_LOOKUP_F_DST_NOREF;
1468 struct dst_entry *dst = NULL;
1469 struct rt6_info *rt;
1470
1471 /* VRF device does not have a link-local address and
1472 * sending packets to link-local or mcast addresses over
1473 * a VRF device does not make sense
1474 */
1475 if (fl6->flowi6_oif == dev->ifindex) {
1476 dst = &net->ipv6.ip6_null_entry->dst;
1477 return dst;
1478 }
1479
1480 if (!ipv6_addr_any(&fl6->saddr))
1481 flags |= RT6_LOOKUP_F_HAS_SADDR;
1482
1483 rt = vrf_ip6_route_lookup(net, dev, fl6, fl6->flowi6_oif, NULL, flags);
1484 if (rt)
1485 dst = &rt->dst;
1486
1487 return dst;
1488}
1489#endif
1490
1491static const struct l3mdev_ops vrf_l3mdev_ops = {
1492 .l3mdev_fib_table = vrf_fib_table,
1493 .l3mdev_l3_rcv = vrf_l3_rcv,
1494 .l3mdev_l3_out = vrf_l3_out,
1495#if IS_ENABLED(CONFIG_IPV6)
1496 .l3mdev_link_scope_lookup = vrf_link_scope_lookup,
1497#endif
1498};
1499
1500static void vrf_get_drvinfo(struct net_device *dev,
1501 struct ethtool_drvinfo *info)
1502{
1503 strscpy(info->driver, DRV_NAME, sizeof(info->driver));
1504 strscpy(info->version, DRV_VERSION, sizeof(info->version));
1505}
1506
1507static const struct ethtool_ops vrf_ethtool_ops = {
1508 .get_drvinfo = vrf_get_drvinfo,
1509};
1510
1511static inline size_t vrf_fib_rule_nl_size(void)
1512{
1513 size_t sz;
1514
1515 sz = NLMSG_ALIGN(sizeof(struct fib_rule_hdr));
1516 sz += nla_total_size(sizeof(u8)); /* FRA_L3MDEV */
1517 sz += nla_total_size(sizeof(u32)); /* FRA_PRIORITY */
1518 sz += nla_total_size(sizeof(u8)); /* FRA_PROTOCOL */
1519
1520 return sz;
1521}
1522
1523static int vrf_fib_rule(const struct net_device *dev, __u8 family, bool add_it)
1524{
1525 struct fib_rule_hdr *frh;
1526 struct nlmsghdr *nlh;
1527 struct sk_buff *skb;
1528 int err;
1529
1530 if ((family == AF_INET6 || family == RTNL_FAMILY_IP6MR) &&
1531 !ipv6_mod_enabled())
1532 return 0;
1533
1534 skb = nlmsg_new(vrf_fib_rule_nl_size(), GFP_KERNEL);
1535 if (!skb)
1536 return -ENOMEM;
1537
1538 nlh = nlmsg_put(skb, 0, 0, 0, sizeof(*frh), 0);
1539 if (!nlh)
1540 goto nla_put_failure;
1541
1542 /* rule only needs to appear once */
1543 nlh->nlmsg_flags |= NLM_F_EXCL;
1544
1545 frh = nlmsg_data(nlh);
1546 memset(frh, 0, sizeof(*frh));
1547 frh->family = family;
1548 frh->action = FR_ACT_TO_TBL;
1549
1550 if (nla_put_u8(skb, FRA_PROTOCOL, RTPROT_KERNEL))
1551 goto nla_put_failure;
1552
1553 if (nla_put_u8(skb, FRA_L3MDEV, 1))
1554 goto nla_put_failure;
1555
1556 if (nla_put_u32(skb, FRA_PRIORITY, FIB_RULE_PREF))
1557 goto nla_put_failure;
1558
1559 nlmsg_end(skb, nlh);
1560
1561 /* fib_nl_{new,del}rule handling looks for net from skb->sk */
1562 skb->sk = dev_net(dev)->rtnl;
1563 if (add_it) {
1564 err = fib_nl_newrule(skb, nlh, NULL);
1565 if (err == -EEXIST)
1566 err = 0;
1567 } else {
1568 err = fib_nl_delrule(skb, nlh, NULL);
1569 if (err == -ENOENT)
1570 err = 0;
1571 }
1572 nlmsg_free(skb);
1573
1574 return err;
1575
1576nla_put_failure:
1577 nlmsg_free(skb);
1578
1579 return -EMSGSIZE;
1580}
1581
1582static int vrf_add_fib_rules(const struct net_device *dev)
1583{
1584 int err;
1585
1586 err = vrf_fib_rule(dev, AF_INET, true);
1587 if (err < 0)
1588 goto out_err;
1589
1590 err = vrf_fib_rule(dev, AF_INET6, true);
1591 if (err < 0)
1592 goto ipv6_err;
1593
1594#if IS_ENABLED(CONFIG_IP_MROUTE_MULTIPLE_TABLES)
1595 err = vrf_fib_rule(dev, RTNL_FAMILY_IPMR, true);
1596 if (err < 0)
1597 goto ipmr_err;
1598#endif
1599
1600#if IS_ENABLED(CONFIG_IPV6_MROUTE_MULTIPLE_TABLES)
1601 err = vrf_fib_rule(dev, RTNL_FAMILY_IP6MR, true);
1602 if (err < 0)
1603 goto ip6mr_err;
1604#endif
1605
1606 return 0;
1607
1608#if IS_ENABLED(CONFIG_IPV6_MROUTE_MULTIPLE_TABLES)
1609ip6mr_err:
1610 vrf_fib_rule(dev, RTNL_FAMILY_IPMR, false);
1611#endif
1612
1613#if IS_ENABLED(CONFIG_IP_MROUTE_MULTIPLE_TABLES)
1614ipmr_err:
1615 vrf_fib_rule(dev, AF_INET6, false);
1616#endif
1617
1618ipv6_err:
1619 vrf_fib_rule(dev, AF_INET, false);
1620
1621out_err:
1622 netdev_err(dev, "Failed to add FIB rules.\n");
1623 return err;
1624}
1625
1626static void vrf_setup(struct net_device *dev)
1627{
1628 ether_setup(dev);
1629
1630 /* Initialize the device structure. */
1631 dev->netdev_ops = &vrf_netdev_ops;
1632 dev->l3mdev_ops = &vrf_l3mdev_ops;
1633 dev->ethtool_ops = &vrf_ethtool_ops;
1634 dev->needs_free_netdev = true;
1635
1636 /* Fill in device structure with ethernet-generic values. */
1637 eth_hw_addr_random(dev);
1638
1639 /* don't acquire vrf device's netif_tx_lock when transmitting */
1640 dev->lltx = true;
1641
1642 /* don't allow vrf devices to change network namespaces. */
1643 dev->netns_local = true;
1644
1645 /* does not make sense for a VLAN to be added to a vrf device */
1646 dev->features |= NETIF_F_VLAN_CHALLENGED;
1647
1648 /* enable offload features */
1649 dev->features |= NETIF_F_GSO_SOFTWARE;
1650 dev->features |= NETIF_F_RXCSUM | NETIF_F_HW_CSUM | NETIF_F_SCTP_CRC;
1651 dev->features |= NETIF_F_SG | NETIF_F_FRAGLIST | NETIF_F_HIGHDMA;
1652
1653 dev->hw_features = dev->features;
1654 dev->hw_enc_features = dev->features;
1655
1656 /* default to no qdisc; user can add if desired */
1657 dev->priv_flags |= IFF_NO_QUEUE;
1658 dev->priv_flags |= IFF_NO_RX_HANDLER;
1659 dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1660
1661 /* VRF devices do not care about MTU, but if the MTU is set
1662 * too low then the ipv4 and ipv6 protocols are disabled
1663 * which breaks networking.
1664 */
1665 dev->min_mtu = IPV6_MIN_MTU;
1666 dev->max_mtu = IP6_MAX_MTU;
1667 dev->mtu = dev->max_mtu;
1668
1669 dev->pcpu_stat_type = NETDEV_PCPU_STAT_DSTATS;
1670}
1671
1672static int vrf_validate(struct nlattr *tb[], struct nlattr *data[],
1673 struct netlink_ext_ack *extack)
1674{
1675 if (tb[IFLA_ADDRESS]) {
1676 if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN) {
1677 NL_SET_ERR_MSG(extack, "Invalid hardware address");
1678 return -EINVAL;
1679 }
1680 if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS]))) {
1681 NL_SET_ERR_MSG(extack, "Invalid hardware address");
1682 return -EADDRNOTAVAIL;
1683 }
1684 }
1685 return 0;
1686}
1687
1688static void vrf_dellink(struct net_device *dev, struct list_head *head)
1689{
1690 struct net_device *port_dev;
1691 struct list_head *iter;
1692
1693 netdev_for_each_lower_dev(dev, port_dev, iter)
1694 vrf_del_slave(dev, port_dev);
1695
1696 vrf_map_unregister_dev(dev);
1697
1698 unregister_netdevice_queue(dev, head);
1699}
1700
1701static int vrf_newlink(struct net *src_net, struct net_device *dev,
1702 struct nlattr *tb[], struct nlattr *data[],
1703 struct netlink_ext_ack *extack)
1704{
1705 struct net_vrf *vrf = netdev_priv(dev);
1706 struct netns_vrf *nn_vrf;
1707 bool *add_fib_rules;
1708 struct net *net;
1709 int err;
1710
1711 if (!data || !data[IFLA_VRF_TABLE]) {
1712 NL_SET_ERR_MSG(extack, "VRF table id is missing");
1713 return -EINVAL;
1714 }
1715
1716 vrf->tb_id = nla_get_u32(data[IFLA_VRF_TABLE]);
1717 if (vrf->tb_id == RT_TABLE_UNSPEC) {
1718 NL_SET_ERR_MSG_ATTR(extack, data[IFLA_VRF_TABLE],
1719 "Invalid VRF table id");
1720 return -EINVAL;
1721 }
1722
1723 dev->priv_flags |= IFF_L3MDEV_MASTER;
1724
1725 err = register_netdevice(dev);
1726 if (err)
1727 goto out;
1728
1729 /* mapping between table_id and vrf;
1730 * note: such binding could not be done in the dev init function
1731 * because dev->ifindex id is not available yet.
1732 */
1733 vrf->ifindex = dev->ifindex;
1734
1735 err = vrf_map_register_dev(dev, extack);
1736 if (err) {
1737 unregister_netdevice(dev);
1738 goto out;
1739 }
1740
1741 net = dev_net(dev);
1742 nn_vrf = net_generic(net, vrf_net_id);
1743
1744 add_fib_rules = &nn_vrf->add_fib_rules;
1745 if (*add_fib_rules) {
1746 err = vrf_add_fib_rules(dev);
1747 if (err) {
1748 vrf_map_unregister_dev(dev);
1749 unregister_netdevice(dev);
1750 goto out;
1751 }
1752 *add_fib_rules = false;
1753 }
1754
1755out:
1756 return err;
1757}
1758
1759static size_t vrf_nl_getsize(const struct net_device *dev)
1760{
1761 return nla_total_size(sizeof(u32)); /* IFLA_VRF_TABLE */
1762}
1763
1764static int vrf_fillinfo(struct sk_buff *skb,
1765 const struct net_device *dev)
1766{
1767 struct net_vrf *vrf = netdev_priv(dev);
1768
1769 return nla_put_u32(skb, IFLA_VRF_TABLE, vrf->tb_id);
1770}
1771
1772static size_t vrf_get_slave_size(const struct net_device *bond_dev,
1773 const struct net_device *slave_dev)
1774{
1775 return nla_total_size(sizeof(u32)); /* IFLA_VRF_PORT_TABLE */
1776}
1777
1778static int vrf_fill_slave_info(struct sk_buff *skb,
1779 const struct net_device *vrf_dev,
1780 const struct net_device *slave_dev)
1781{
1782 struct net_vrf *vrf = netdev_priv(vrf_dev);
1783
1784 if (nla_put_u32(skb, IFLA_VRF_PORT_TABLE, vrf->tb_id))
1785 return -EMSGSIZE;
1786
1787 return 0;
1788}
1789
1790static const struct nla_policy vrf_nl_policy[IFLA_VRF_MAX + 1] = {
1791 [IFLA_VRF_TABLE] = { .type = NLA_U32 },
1792};
1793
1794static struct rtnl_link_ops vrf_link_ops __read_mostly = {
1795 .kind = DRV_NAME,
1796 .priv_size = sizeof(struct net_vrf),
1797
1798 .get_size = vrf_nl_getsize,
1799 .policy = vrf_nl_policy,
1800 .validate = vrf_validate,
1801 .fill_info = vrf_fillinfo,
1802
1803 .get_slave_size = vrf_get_slave_size,
1804 .fill_slave_info = vrf_fill_slave_info,
1805
1806 .newlink = vrf_newlink,
1807 .dellink = vrf_dellink,
1808 .setup = vrf_setup,
1809 .maxtype = IFLA_VRF_MAX,
1810};
1811
1812static int vrf_device_event(struct notifier_block *unused,
1813 unsigned long event, void *ptr)
1814{
1815 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
1816
1817 /* only care about unregister events to drop slave references */
1818 if (event == NETDEV_UNREGISTER) {
1819 struct net_device *vrf_dev;
1820
1821 if (!netif_is_l3_slave(dev))
1822 goto out;
1823
1824 vrf_dev = netdev_master_upper_dev_get(dev);
1825 vrf_del_slave(vrf_dev, dev);
1826 }
1827out:
1828 return NOTIFY_DONE;
1829}
1830
1831static struct notifier_block vrf_notifier_block __read_mostly = {
1832 .notifier_call = vrf_device_event,
1833};
1834
1835static int vrf_map_init(struct vrf_map *vmap)
1836{
1837 spin_lock_init(&vmap->vmap_lock);
1838 hash_init(vmap->ht);
1839
1840 vmap->strict_mode = false;
1841
1842 return 0;
1843}
1844
1845#ifdef CONFIG_SYSCTL
1846static bool vrf_strict_mode(struct vrf_map *vmap)
1847{
1848 bool strict_mode;
1849
1850 vrf_map_lock(vmap);
1851 strict_mode = vmap->strict_mode;
1852 vrf_map_unlock(vmap);
1853
1854 return strict_mode;
1855}
1856
1857static int vrf_strict_mode_change(struct vrf_map *vmap, bool new_mode)
1858{
1859 bool *cur_mode;
1860 int res = 0;
1861
1862 vrf_map_lock(vmap);
1863
1864 cur_mode = &vmap->strict_mode;
1865 if (*cur_mode == new_mode)
1866 goto unlock;
1867
1868 if (*cur_mode) {
1869 /* disable strict mode */
1870 *cur_mode = false;
1871 } else {
1872 if (vmap->shared_tables) {
1873 /* we cannot allow strict_mode because there are some
1874 * vrfs that share one or more tables.
1875 */
1876 res = -EBUSY;
1877 goto unlock;
1878 }
1879
1880 /* no tables are shared among vrfs, so we can go back
1881 * to 1:1 association between a vrf with its table.
1882 */
1883 *cur_mode = true;
1884 }
1885
1886unlock:
1887 vrf_map_unlock(vmap);
1888
1889 return res;
1890}
1891
1892static int vrf_shared_table_handler(const struct ctl_table *table, int write,
1893 void *buffer, size_t *lenp, loff_t *ppos)
1894{
1895 struct net *net = (struct net *)table->extra1;
1896 struct vrf_map *vmap = netns_vrf_map(net);
1897 int proc_strict_mode = 0;
1898 struct ctl_table tmp = {
1899 .procname = table->procname,
1900 .data = &proc_strict_mode,
1901 .maxlen = sizeof(int),
1902 .mode = table->mode,
1903 .extra1 = SYSCTL_ZERO,
1904 .extra2 = SYSCTL_ONE,
1905 };
1906 int ret;
1907
1908 if (!write)
1909 proc_strict_mode = vrf_strict_mode(vmap);
1910
1911 ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
1912
1913 if (write && ret == 0)
1914 ret = vrf_strict_mode_change(vmap, (bool)proc_strict_mode);
1915
1916 return ret;
1917}
1918
1919static const struct ctl_table vrf_table[] = {
1920 {
1921 .procname = "strict_mode",
1922 .data = NULL,
1923 .maxlen = sizeof(int),
1924 .mode = 0644,
1925 .proc_handler = vrf_shared_table_handler,
1926 /* set by the vrf_netns_init */
1927 .extra1 = NULL,
1928 },
1929};
1930
1931static int vrf_netns_init_sysctl(struct net *net, struct netns_vrf *nn_vrf)
1932{
1933 struct ctl_table *table;
1934
1935 table = kmemdup(vrf_table, sizeof(vrf_table), GFP_KERNEL);
1936 if (!table)
1937 return -ENOMEM;
1938
1939 /* init the extra1 parameter with the reference to current netns */
1940 table[0].extra1 = net;
1941
1942 nn_vrf->ctl_hdr = register_net_sysctl_sz(net, "net/vrf", table,
1943 ARRAY_SIZE(vrf_table));
1944 if (!nn_vrf->ctl_hdr) {
1945 kfree(table);
1946 return -ENOMEM;
1947 }
1948
1949 return 0;
1950}
1951
1952static void vrf_netns_exit_sysctl(struct net *net)
1953{
1954 struct netns_vrf *nn_vrf = net_generic(net, vrf_net_id);
1955 const struct ctl_table *table;
1956
1957 table = nn_vrf->ctl_hdr->ctl_table_arg;
1958 unregister_net_sysctl_table(nn_vrf->ctl_hdr);
1959 kfree(table);
1960}
1961#else
1962static int vrf_netns_init_sysctl(struct net *net, struct netns_vrf *nn_vrf)
1963{
1964 return 0;
1965}
1966
1967static void vrf_netns_exit_sysctl(struct net *net)
1968{
1969}
1970#endif
1971
1972/* Initialize per network namespace state */
1973static int __net_init vrf_netns_init(struct net *net)
1974{
1975 struct netns_vrf *nn_vrf = net_generic(net, vrf_net_id);
1976
1977 nn_vrf->add_fib_rules = true;
1978 vrf_map_init(&nn_vrf->vmap);
1979
1980 return vrf_netns_init_sysctl(net, nn_vrf);
1981}
1982
1983static void __net_exit vrf_netns_exit(struct net *net)
1984{
1985 vrf_netns_exit_sysctl(net);
1986}
1987
1988static struct pernet_operations vrf_net_ops __net_initdata = {
1989 .init = vrf_netns_init,
1990 .exit = vrf_netns_exit,
1991 .id = &vrf_net_id,
1992 .size = sizeof(struct netns_vrf),
1993};
1994
1995static int __init vrf_init_module(void)
1996{
1997 int rc;
1998
1999 register_netdevice_notifier(&vrf_notifier_block);
2000
2001 rc = register_pernet_subsys(&vrf_net_ops);
2002 if (rc < 0)
2003 goto error;
2004
2005 rc = l3mdev_table_lookup_register(L3MDEV_TYPE_VRF,
2006 vrf_ifindex_lookup_by_table_id);
2007 if (rc < 0)
2008 goto unreg_pernet;
2009
2010 rc = rtnl_link_register(&vrf_link_ops);
2011 if (rc < 0)
2012 goto table_lookup_unreg;
2013
2014 return 0;
2015
2016table_lookup_unreg:
2017 l3mdev_table_lookup_unregister(L3MDEV_TYPE_VRF,
2018 vrf_ifindex_lookup_by_table_id);
2019
2020unreg_pernet:
2021 unregister_pernet_subsys(&vrf_net_ops);
2022
2023error:
2024 unregister_netdevice_notifier(&vrf_notifier_block);
2025 return rc;
2026}
2027
2028module_init(vrf_init_module);
2029MODULE_AUTHOR("Shrijeet Mukherjee, David Ahern");
2030MODULE_DESCRIPTION("Device driver to instantiate VRF domains");
2031MODULE_LICENSE("GPL");
2032MODULE_ALIAS_RTNL_LINK(DRV_NAME);
2033MODULE_VERSION(DRV_VERSION);
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * vrf.c: device driver to encapsulate a VRF space
4 *
5 * Copyright (c) 2015 Cumulus Networks. All rights reserved.
6 * Copyright (c) 2015 Shrijeet Mukherjee <shm@cumulusnetworks.com>
7 * Copyright (c) 2015 David Ahern <dsa@cumulusnetworks.com>
8 *
9 * Based on dummy, team and ipvlan drivers
10 */
11
12#include <linux/ethtool.h>
13#include <linux/module.h>
14#include <linux/kernel.h>
15#include <linux/netdevice.h>
16#include <linux/etherdevice.h>
17#include <linux/ip.h>
18#include <linux/init.h>
19#include <linux/moduleparam.h>
20#include <linux/netfilter.h>
21#include <linux/rtnetlink.h>
22#include <net/rtnetlink.h>
23#include <linux/u64_stats_sync.h>
24#include <linux/hashtable.h>
25#include <linux/spinlock_types.h>
26
27#include <linux/inetdevice.h>
28#include <net/arp.h>
29#include <net/ip.h>
30#include <net/ip_fib.h>
31#include <net/ip6_fib.h>
32#include <net/ip6_route.h>
33#include <net/route.h>
34#include <net/addrconf.h>
35#include <net/l3mdev.h>
36#include <net/fib_rules.h>
37#include <net/netns/generic.h>
38
39#define DRV_NAME "vrf"
40#define DRV_VERSION "1.1"
41
42#define FIB_RULE_PREF 1000 /* default preference for FIB rules */
43
44#define HT_MAP_BITS 4
45#define HASH_INITVAL ((u32)0xcafef00d)
46
47struct vrf_map {
48 DECLARE_HASHTABLE(ht, HT_MAP_BITS);
49 spinlock_t vmap_lock;
50
51 /* shared_tables:
52 * count how many distinct tables do not comply with the strict mode
53 * requirement.
54 * shared_tables value must be 0 in order to enable the strict mode.
55 *
56 * example of the evolution of shared_tables:
57 * | time
58 * add vrf0 --> table 100 shared_tables = 0 | t0
59 * add vrf1 --> table 101 shared_tables = 0 | t1
60 * add vrf2 --> table 100 shared_tables = 1 | t2
61 * add vrf3 --> table 100 shared_tables = 1 | t3
62 * add vrf4 --> table 101 shared_tables = 2 v t4
63 *
64 * shared_tables is a "step function" (or "staircase function")
65 * and it is increased by one when the second vrf is associated to a
66 * table.
67 *
68 * at t2, vrf0 and vrf2 are bound to table 100: shared_tables = 1.
69 *
70 * at t3, another dev (vrf3) is bound to the same table 100 but the
71 * value of shared_tables is still 1.
72 * This means that no matter how many new vrfs will register on the
73 * table 100, the shared_tables will not increase (considering only
74 * table 100).
75 *
76 * at t4, vrf4 is bound to table 101, and shared_tables = 2.
77 *
78 * Looking at the value of shared_tables we can immediately know if
79 * the strict_mode can or cannot be enforced. Indeed, strict_mode
80 * can be enforced iff shared_tables = 0.
81 *
82 * Conversely, shared_tables is decreased when a vrf is de-associated
83 * from a table with exactly two associated vrfs.
84 */
85 u32 shared_tables;
86
87 bool strict_mode;
88};
89
90struct vrf_map_elem {
91 struct hlist_node hnode;
92 struct list_head vrf_list; /* VRFs registered to this table */
93
94 u32 table_id;
95 int users;
96 int ifindex;
97};
98
99static unsigned int vrf_net_id;
100
101/* per netns vrf data */
102struct netns_vrf {
103 /* protected by rtnl lock */
104 bool add_fib_rules;
105
106 struct vrf_map vmap;
107 struct ctl_table_header *ctl_hdr;
108};
109
110struct net_vrf {
111 struct rtable __rcu *rth;
112 struct rt6_info __rcu *rt6;
113#if IS_ENABLED(CONFIG_IPV6)
114 struct fib6_table *fib6_table;
115#endif
116 u32 tb_id;
117
118 struct list_head me_list; /* entry in vrf_map_elem */
119 int ifindex;
120};
121
122struct pcpu_dstats {
123 u64 tx_pkts;
124 u64 tx_bytes;
125 u64 tx_drps;
126 u64 rx_pkts;
127 u64 rx_bytes;
128 u64 rx_drps;
129 struct u64_stats_sync syncp;
130};
131
132static void vrf_rx_stats(struct net_device *dev, int len)
133{
134 struct pcpu_dstats *dstats = this_cpu_ptr(dev->dstats);
135
136 u64_stats_update_begin(&dstats->syncp);
137 dstats->rx_pkts++;
138 dstats->rx_bytes += len;
139 u64_stats_update_end(&dstats->syncp);
140}
141
142static void vrf_tx_error(struct net_device *vrf_dev, struct sk_buff *skb)
143{
144 vrf_dev->stats.tx_errors++;
145 kfree_skb(skb);
146}
147
148static void vrf_get_stats64(struct net_device *dev,
149 struct rtnl_link_stats64 *stats)
150{
151 int i;
152
153 for_each_possible_cpu(i) {
154 const struct pcpu_dstats *dstats;
155 u64 tbytes, tpkts, tdrops, rbytes, rpkts;
156 unsigned int start;
157
158 dstats = per_cpu_ptr(dev->dstats, i);
159 do {
160 start = u64_stats_fetch_begin_irq(&dstats->syncp);
161 tbytes = dstats->tx_bytes;
162 tpkts = dstats->tx_pkts;
163 tdrops = dstats->tx_drps;
164 rbytes = dstats->rx_bytes;
165 rpkts = dstats->rx_pkts;
166 } while (u64_stats_fetch_retry_irq(&dstats->syncp, start));
167 stats->tx_bytes += tbytes;
168 stats->tx_packets += tpkts;
169 stats->tx_dropped += tdrops;
170 stats->rx_bytes += rbytes;
171 stats->rx_packets += rpkts;
172 }
173}
174
175static struct vrf_map *netns_vrf_map(struct net *net)
176{
177 struct netns_vrf *nn_vrf = net_generic(net, vrf_net_id);
178
179 return &nn_vrf->vmap;
180}
181
182static struct vrf_map *netns_vrf_map_by_dev(struct net_device *dev)
183{
184 return netns_vrf_map(dev_net(dev));
185}
186
187static int vrf_map_elem_get_vrf_ifindex(struct vrf_map_elem *me)
188{
189 struct list_head *me_head = &me->vrf_list;
190 struct net_vrf *vrf;
191
192 if (list_empty(me_head))
193 return -ENODEV;
194
195 vrf = list_first_entry(me_head, struct net_vrf, me_list);
196
197 return vrf->ifindex;
198}
199
200static struct vrf_map_elem *vrf_map_elem_alloc(gfp_t flags)
201{
202 struct vrf_map_elem *me;
203
204 me = kmalloc(sizeof(*me), flags);
205 if (!me)
206 return NULL;
207
208 return me;
209}
210
211static void vrf_map_elem_free(struct vrf_map_elem *me)
212{
213 kfree(me);
214}
215
216static void vrf_map_elem_init(struct vrf_map_elem *me, int table_id,
217 int ifindex, int users)
218{
219 me->table_id = table_id;
220 me->ifindex = ifindex;
221 me->users = users;
222 INIT_LIST_HEAD(&me->vrf_list);
223}
224
225static struct vrf_map_elem *vrf_map_lookup_elem(struct vrf_map *vmap,
226 u32 table_id)
227{
228 struct vrf_map_elem *me;
229 u32 key;
230
231 key = jhash_1word(table_id, HASH_INITVAL);
232 hash_for_each_possible(vmap->ht, me, hnode, key) {
233 if (me->table_id == table_id)
234 return me;
235 }
236
237 return NULL;
238}
239
240static void vrf_map_add_elem(struct vrf_map *vmap, struct vrf_map_elem *me)
241{
242 u32 table_id = me->table_id;
243 u32 key;
244
245 key = jhash_1word(table_id, HASH_INITVAL);
246 hash_add(vmap->ht, &me->hnode, key);
247}
248
249static void vrf_map_del_elem(struct vrf_map_elem *me)
250{
251 hash_del(&me->hnode);
252}
253
254static void vrf_map_lock(struct vrf_map *vmap) __acquires(&vmap->vmap_lock)
255{
256 spin_lock(&vmap->vmap_lock);
257}
258
259static void vrf_map_unlock(struct vrf_map *vmap) __releases(&vmap->vmap_lock)
260{
261 spin_unlock(&vmap->vmap_lock);
262}
263
264/* called with rtnl lock held */
265static int
266vrf_map_register_dev(struct net_device *dev, struct netlink_ext_ack *extack)
267{
268 struct vrf_map *vmap = netns_vrf_map_by_dev(dev);
269 struct net_vrf *vrf = netdev_priv(dev);
270 struct vrf_map_elem *new_me, *me;
271 u32 table_id = vrf->tb_id;
272 bool free_new_me = false;
273 int users;
274 int res;
275
276 /* we pre-allocate elements used in the spin-locked section (so that we
277 * keep the spinlock as short as possible).
278 */
279 new_me = vrf_map_elem_alloc(GFP_KERNEL);
280 if (!new_me)
281 return -ENOMEM;
282
283 vrf_map_elem_init(new_me, table_id, dev->ifindex, 0);
284
285 vrf_map_lock(vmap);
286
287 me = vrf_map_lookup_elem(vmap, table_id);
288 if (!me) {
289 me = new_me;
290 vrf_map_add_elem(vmap, me);
291 goto link_vrf;
292 }
293
294 /* we already have an entry in the vrf_map, so it means there is (at
295 * least) a vrf registered on the specific table.
296 */
297 free_new_me = true;
298 if (vmap->strict_mode) {
299 /* vrfs cannot share the same table */
300 NL_SET_ERR_MSG(extack, "Table is used by another VRF");
301 res = -EBUSY;
302 goto unlock;
303 }
304
305link_vrf:
306 users = ++me->users;
307 if (users == 2)
308 ++vmap->shared_tables;
309
310 list_add(&vrf->me_list, &me->vrf_list);
311
312 res = 0;
313
314unlock:
315 vrf_map_unlock(vmap);
316
317 /* clean-up, if needed */
318 if (free_new_me)
319 vrf_map_elem_free(new_me);
320
321 return res;
322}
323
324/* called with rtnl lock held */
325static void vrf_map_unregister_dev(struct net_device *dev)
326{
327 struct vrf_map *vmap = netns_vrf_map_by_dev(dev);
328 struct net_vrf *vrf = netdev_priv(dev);
329 u32 table_id = vrf->tb_id;
330 struct vrf_map_elem *me;
331 int users;
332
333 vrf_map_lock(vmap);
334
335 me = vrf_map_lookup_elem(vmap, table_id);
336 if (!me)
337 goto unlock;
338
339 list_del(&vrf->me_list);
340
341 users = --me->users;
342 if (users == 1) {
343 --vmap->shared_tables;
344 } else if (users == 0) {
345 vrf_map_del_elem(me);
346
347 /* no one will refer to this element anymore */
348 vrf_map_elem_free(me);
349 }
350
351unlock:
352 vrf_map_unlock(vmap);
353}
354
355/* return the vrf device index associated with the table_id */
356static int vrf_ifindex_lookup_by_table_id(struct net *net, u32 table_id)
357{
358 struct vrf_map *vmap = netns_vrf_map(net);
359 struct vrf_map_elem *me;
360 int ifindex;
361
362 vrf_map_lock(vmap);
363
364 if (!vmap->strict_mode) {
365 ifindex = -EPERM;
366 goto unlock;
367 }
368
369 me = vrf_map_lookup_elem(vmap, table_id);
370 if (!me) {
371 ifindex = -ENODEV;
372 goto unlock;
373 }
374
375 ifindex = vrf_map_elem_get_vrf_ifindex(me);
376
377unlock:
378 vrf_map_unlock(vmap);
379
380 return ifindex;
381}
382
383/* by default VRF devices do not have a qdisc and are expected
384 * to be created with only a single queue.
385 */
386static bool qdisc_tx_is_default(const struct net_device *dev)
387{
388 struct netdev_queue *txq;
389 struct Qdisc *qdisc;
390
391 if (dev->num_tx_queues > 1)
392 return false;
393
394 txq = netdev_get_tx_queue(dev, 0);
395 qdisc = rcu_access_pointer(txq->qdisc);
396
397 return !qdisc->enqueue;
398}
399
400/* Local traffic destined to local address. Reinsert the packet to rx
401 * path, similar to loopback handling.
402 */
403static int vrf_local_xmit(struct sk_buff *skb, struct net_device *dev,
404 struct dst_entry *dst)
405{
406 int len = skb->len;
407
408 skb_orphan(skb);
409
410 skb_dst_set(skb, dst);
411
412 /* set pkt_type to avoid skb hitting packet taps twice -
413 * once on Tx and again in Rx processing
414 */
415 skb->pkt_type = PACKET_LOOPBACK;
416
417 skb->protocol = eth_type_trans(skb, dev);
418
419 if (likely(netif_rx(skb) == NET_RX_SUCCESS))
420 vrf_rx_stats(dev, len);
421 else
422 this_cpu_inc(dev->dstats->rx_drps);
423
424 return NETDEV_TX_OK;
425}
426
427#if IS_ENABLED(CONFIG_IPV6)
428static int vrf_ip6_local_out(struct net *net, struct sock *sk,
429 struct sk_buff *skb)
430{
431 int err;
432
433 err = nf_hook(NFPROTO_IPV6, NF_INET_LOCAL_OUT, net,
434 sk, skb, NULL, skb_dst(skb)->dev, dst_output);
435
436 if (likely(err == 1))
437 err = dst_output(net, sk, skb);
438
439 return err;
440}
441
442static netdev_tx_t vrf_process_v6_outbound(struct sk_buff *skb,
443 struct net_device *dev)
444{
445 const struct ipv6hdr *iph;
446 struct net *net = dev_net(skb->dev);
447 struct flowi6 fl6;
448 int ret = NET_XMIT_DROP;
449 struct dst_entry *dst;
450 struct dst_entry *dst_null = &net->ipv6.ip6_null_entry->dst;
451
452 if (!pskb_may_pull(skb, ETH_HLEN + sizeof(struct ipv6hdr)))
453 goto err;
454
455 iph = ipv6_hdr(skb);
456
457 memset(&fl6, 0, sizeof(fl6));
458 /* needed to match OIF rule */
459 fl6.flowi6_oif = dev->ifindex;
460 fl6.flowi6_iif = LOOPBACK_IFINDEX;
461 fl6.daddr = iph->daddr;
462 fl6.saddr = iph->saddr;
463 fl6.flowlabel = ip6_flowinfo(iph);
464 fl6.flowi6_mark = skb->mark;
465 fl6.flowi6_proto = iph->nexthdr;
466 fl6.flowi6_flags = FLOWI_FLAG_SKIP_NH_OIF;
467
468 dst = ip6_dst_lookup_flow(net, NULL, &fl6, NULL);
469 if (IS_ERR(dst) || dst == dst_null)
470 goto err;
471
472 skb_dst_drop(skb);
473
474 /* if dst.dev is the VRF device again this is locally originated traffic
475 * destined to a local address. Short circuit to Rx path.
476 */
477 if (dst->dev == dev)
478 return vrf_local_xmit(skb, dev, dst);
479
480 skb_dst_set(skb, dst);
481
482 /* strip the ethernet header added for pass through VRF device */
483 __skb_pull(skb, skb_network_offset(skb));
484
485 ret = vrf_ip6_local_out(net, skb->sk, skb);
486 if (unlikely(net_xmit_eval(ret)))
487 dev->stats.tx_errors++;
488 else
489 ret = NET_XMIT_SUCCESS;
490
491 return ret;
492err:
493 vrf_tx_error(dev, skb);
494 return NET_XMIT_DROP;
495}
496#else
497static netdev_tx_t vrf_process_v6_outbound(struct sk_buff *skb,
498 struct net_device *dev)
499{
500 vrf_tx_error(dev, skb);
501 return NET_XMIT_DROP;
502}
503#endif
504
505/* based on ip_local_out; can't use it b/c the dst is switched pointing to us */
506static int vrf_ip_local_out(struct net *net, struct sock *sk,
507 struct sk_buff *skb)
508{
509 int err;
510
511 err = nf_hook(NFPROTO_IPV4, NF_INET_LOCAL_OUT, net, sk,
512 skb, NULL, skb_dst(skb)->dev, dst_output);
513 if (likely(err == 1))
514 err = dst_output(net, sk, skb);
515
516 return err;
517}
518
519static netdev_tx_t vrf_process_v4_outbound(struct sk_buff *skb,
520 struct net_device *vrf_dev)
521{
522 struct iphdr *ip4h;
523 int ret = NET_XMIT_DROP;
524 struct flowi4 fl4;
525 struct net *net = dev_net(vrf_dev);
526 struct rtable *rt;
527
528 if (!pskb_may_pull(skb, ETH_HLEN + sizeof(struct iphdr)))
529 goto err;
530
531 ip4h = ip_hdr(skb);
532
533 memset(&fl4, 0, sizeof(fl4));
534 /* needed to match OIF rule */
535 fl4.flowi4_oif = vrf_dev->ifindex;
536 fl4.flowi4_iif = LOOPBACK_IFINDEX;
537 fl4.flowi4_tos = RT_TOS(ip4h->tos);
538 fl4.flowi4_flags = FLOWI_FLAG_ANYSRC | FLOWI_FLAG_SKIP_NH_OIF;
539 fl4.flowi4_proto = ip4h->protocol;
540 fl4.daddr = ip4h->daddr;
541 fl4.saddr = ip4h->saddr;
542
543 rt = ip_route_output_flow(net, &fl4, NULL);
544 if (IS_ERR(rt))
545 goto err;
546
547 skb_dst_drop(skb);
548
549 /* if dst.dev is the VRF device again this is locally originated traffic
550 * destined to a local address. Short circuit to Rx path.
551 */
552 if (rt->dst.dev == vrf_dev)
553 return vrf_local_xmit(skb, vrf_dev, &rt->dst);
554
555 skb_dst_set(skb, &rt->dst);
556
557 /* strip the ethernet header added for pass through VRF device */
558 __skb_pull(skb, skb_network_offset(skb));
559
560 if (!ip4h->saddr) {
561 ip4h->saddr = inet_select_addr(skb_dst(skb)->dev, 0,
562 RT_SCOPE_LINK);
563 }
564
565 ret = vrf_ip_local_out(dev_net(skb_dst(skb)->dev), skb->sk, skb);
566 if (unlikely(net_xmit_eval(ret)))
567 vrf_dev->stats.tx_errors++;
568 else
569 ret = NET_XMIT_SUCCESS;
570
571out:
572 return ret;
573err:
574 vrf_tx_error(vrf_dev, skb);
575 goto out;
576}
577
578static netdev_tx_t is_ip_tx_frame(struct sk_buff *skb, struct net_device *dev)
579{
580 switch (skb->protocol) {
581 case htons(ETH_P_IP):
582 return vrf_process_v4_outbound(skb, dev);
583 case htons(ETH_P_IPV6):
584 return vrf_process_v6_outbound(skb, dev);
585 default:
586 vrf_tx_error(dev, skb);
587 return NET_XMIT_DROP;
588 }
589}
590
591static netdev_tx_t vrf_xmit(struct sk_buff *skb, struct net_device *dev)
592{
593 int len = skb->len;
594 netdev_tx_t ret = is_ip_tx_frame(skb, dev);
595
596 if (likely(ret == NET_XMIT_SUCCESS || ret == NET_XMIT_CN)) {
597 struct pcpu_dstats *dstats = this_cpu_ptr(dev->dstats);
598
599 u64_stats_update_begin(&dstats->syncp);
600 dstats->tx_pkts++;
601 dstats->tx_bytes += len;
602 u64_stats_update_end(&dstats->syncp);
603 } else {
604 this_cpu_inc(dev->dstats->tx_drps);
605 }
606
607 return ret;
608}
609
610static void vrf_finish_direct(struct sk_buff *skb)
611{
612 struct net_device *vrf_dev = skb->dev;
613
614 if (!list_empty(&vrf_dev->ptype_all) &&
615 likely(skb_headroom(skb) >= ETH_HLEN)) {
616 struct ethhdr *eth = skb_push(skb, ETH_HLEN);
617
618 ether_addr_copy(eth->h_source, vrf_dev->dev_addr);
619 eth_zero_addr(eth->h_dest);
620 eth->h_proto = skb->protocol;
621
622 rcu_read_lock_bh();
623 dev_queue_xmit_nit(skb, vrf_dev);
624 rcu_read_unlock_bh();
625
626 skb_pull(skb, ETH_HLEN);
627 }
628
629 /* reset skb device */
630 nf_reset_ct(skb);
631}
632
633#if IS_ENABLED(CONFIG_IPV6)
634/* modelled after ip6_finish_output2 */
635static int vrf_finish_output6(struct net *net, struct sock *sk,
636 struct sk_buff *skb)
637{
638 struct dst_entry *dst = skb_dst(skb);
639 struct net_device *dev = dst->dev;
640 const struct in6_addr *nexthop;
641 struct neighbour *neigh;
642 int ret;
643
644 nf_reset_ct(skb);
645
646 skb->protocol = htons(ETH_P_IPV6);
647 skb->dev = dev;
648
649 rcu_read_lock_bh();
650 nexthop = rt6_nexthop((struct rt6_info *)dst, &ipv6_hdr(skb)->daddr);
651 neigh = __ipv6_neigh_lookup_noref(dst->dev, nexthop);
652 if (unlikely(!neigh))
653 neigh = __neigh_create(&nd_tbl, nexthop, dst->dev, false);
654 if (!IS_ERR(neigh)) {
655 sock_confirm_neigh(skb, neigh);
656 ret = neigh_output(neigh, skb, false);
657 rcu_read_unlock_bh();
658 return ret;
659 }
660 rcu_read_unlock_bh();
661
662 IP6_INC_STATS(dev_net(dst->dev),
663 ip6_dst_idev(dst), IPSTATS_MIB_OUTNOROUTES);
664 kfree_skb(skb);
665 return -EINVAL;
666}
667
668/* modelled after ip6_output */
669static int vrf_output6(struct net *net, struct sock *sk, struct sk_buff *skb)
670{
671 return NF_HOOK_COND(NFPROTO_IPV6, NF_INET_POST_ROUTING,
672 net, sk, skb, NULL, skb_dst(skb)->dev,
673 vrf_finish_output6,
674 !(IP6CB(skb)->flags & IP6SKB_REROUTED));
675}
676
677/* set dst on skb to send packet to us via dev_xmit path. Allows
678 * packet to go through device based features such as qdisc, netfilter
679 * hooks and packet sockets with skb->dev set to vrf device.
680 */
681static struct sk_buff *vrf_ip6_out_redirect(struct net_device *vrf_dev,
682 struct sk_buff *skb)
683{
684 struct net_vrf *vrf = netdev_priv(vrf_dev);
685 struct dst_entry *dst = NULL;
686 struct rt6_info *rt6;
687
688 rcu_read_lock();
689
690 rt6 = rcu_dereference(vrf->rt6);
691 if (likely(rt6)) {
692 dst = &rt6->dst;
693 dst_hold(dst);
694 }
695
696 rcu_read_unlock();
697
698 if (unlikely(!dst)) {
699 vrf_tx_error(vrf_dev, skb);
700 return NULL;
701 }
702
703 skb_dst_drop(skb);
704 skb_dst_set(skb, dst);
705
706 return skb;
707}
708
709static int vrf_output6_direct_finish(struct net *net, struct sock *sk,
710 struct sk_buff *skb)
711{
712 vrf_finish_direct(skb);
713
714 return vrf_ip6_local_out(net, sk, skb);
715}
716
717static int vrf_output6_direct(struct net *net, struct sock *sk,
718 struct sk_buff *skb)
719{
720 int err = 1;
721
722 skb->protocol = htons(ETH_P_IPV6);
723
724 if (!(IPCB(skb)->flags & IPSKB_REROUTED))
725 err = nf_hook(NFPROTO_IPV6, NF_INET_POST_ROUTING, net, sk, skb,
726 NULL, skb->dev, vrf_output6_direct_finish);
727
728 if (likely(err == 1))
729 vrf_finish_direct(skb);
730
731 return err;
732}
733
734static int vrf_ip6_out_direct_finish(struct net *net, struct sock *sk,
735 struct sk_buff *skb)
736{
737 int err;
738
739 err = vrf_output6_direct(net, sk, skb);
740 if (likely(err == 1))
741 err = vrf_ip6_local_out(net, sk, skb);
742
743 return err;
744}
745
746static struct sk_buff *vrf_ip6_out_direct(struct net_device *vrf_dev,
747 struct sock *sk,
748 struct sk_buff *skb)
749{
750 struct net *net = dev_net(vrf_dev);
751 int err;
752
753 skb->dev = vrf_dev;
754
755 err = nf_hook(NFPROTO_IPV6, NF_INET_LOCAL_OUT, net, sk,
756 skb, NULL, vrf_dev, vrf_ip6_out_direct_finish);
757
758 if (likely(err == 1))
759 err = vrf_output6_direct(net, sk, skb);
760
761 if (likely(err == 1))
762 return skb;
763
764 return NULL;
765}
766
767static struct sk_buff *vrf_ip6_out(struct net_device *vrf_dev,
768 struct sock *sk,
769 struct sk_buff *skb)
770{
771 /* don't divert link scope packets */
772 if (rt6_need_strict(&ipv6_hdr(skb)->daddr))
773 return skb;
774
775 if (qdisc_tx_is_default(vrf_dev) ||
776 IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED)
777 return vrf_ip6_out_direct(vrf_dev, sk, skb);
778
779 return vrf_ip6_out_redirect(vrf_dev, skb);
780}
781
782/* holding rtnl */
783static void vrf_rt6_release(struct net_device *dev, struct net_vrf *vrf)
784{
785 struct rt6_info *rt6 = rtnl_dereference(vrf->rt6);
786 struct net *net = dev_net(dev);
787 struct dst_entry *dst;
788
789 RCU_INIT_POINTER(vrf->rt6, NULL);
790 synchronize_rcu();
791
792 /* move dev in dst's to loopback so this VRF device can be deleted
793 * - based on dst_ifdown
794 */
795 if (rt6) {
796 dst = &rt6->dst;
797 dev_put(dst->dev);
798 dst->dev = net->loopback_dev;
799 dev_hold(dst->dev);
800 dst_release(dst);
801 }
802}
803
804static int vrf_rt6_create(struct net_device *dev)
805{
806 int flags = DST_NOPOLICY | DST_NOXFRM;
807 struct net_vrf *vrf = netdev_priv(dev);
808 struct net *net = dev_net(dev);
809 struct rt6_info *rt6;
810 int rc = -ENOMEM;
811
812 /* IPv6 can be CONFIG enabled and then disabled runtime */
813 if (!ipv6_mod_enabled())
814 return 0;
815
816 vrf->fib6_table = fib6_new_table(net, vrf->tb_id);
817 if (!vrf->fib6_table)
818 goto out;
819
820 /* create a dst for routing packets out a VRF device */
821 rt6 = ip6_dst_alloc(net, dev, flags);
822 if (!rt6)
823 goto out;
824
825 rt6->dst.output = vrf_output6;
826
827 rcu_assign_pointer(vrf->rt6, rt6);
828
829 rc = 0;
830out:
831 return rc;
832}
833#else
834static struct sk_buff *vrf_ip6_out(struct net_device *vrf_dev,
835 struct sock *sk,
836 struct sk_buff *skb)
837{
838 return skb;
839}
840
841static void vrf_rt6_release(struct net_device *dev, struct net_vrf *vrf)
842{
843}
844
845static int vrf_rt6_create(struct net_device *dev)
846{
847 return 0;
848}
849#endif
850
851/* modelled after ip_finish_output2 */
852static int vrf_finish_output(struct net *net, struct sock *sk, struct sk_buff *skb)
853{
854 struct dst_entry *dst = skb_dst(skb);
855 struct rtable *rt = (struct rtable *)dst;
856 struct net_device *dev = dst->dev;
857 unsigned int hh_len = LL_RESERVED_SPACE(dev);
858 struct neighbour *neigh;
859 bool is_v6gw = false;
860 int ret = -EINVAL;
861
862 nf_reset_ct(skb);
863
864 /* Be paranoid, rather than too clever. */
865 if (unlikely(skb_headroom(skb) < hh_len && dev->header_ops)) {
866 struct sk_buff *skb2;
867
868 skb2 = skb_realloc_headroom(skb, LL_RESERVED_SPACE(dev));
869 if (!skb2) {
870 ret = -ENOMEM;
871 goto err;
872 }
873 if (skb->sk)
874 skb_set_owner_w(skb2, skb->sk);
875
876 consume_skb(skb);
877 skb = skb2;
878 }
879
880 rcu_read_lock_bh();
881
882 neigh = ip_neigh_for_gw(rt, skb, &is_v6gw);
883 if (!IS_ERR(neigh)) {
884 sock_confirm_neigh(skb, neigh);
885 /* if crossing protocols, can not use the cached header */
886 ret = neigh_output(neigh, skb, is_v6gw);
887 rcu_read_unlock_bh();
888 return ret;
889 }
890
891 rcu_read_unlock_bh();
892err:
893 vrf_tx_error(skb->dev, skb);
894 return ret;
895}
896
897static int vrf_output(struct net *net, struct sock *sk, struct sk_buff *skb)
898{
899 struct net_device *dev = skb_dst(skb)->dev;
900
901 IP_UPD_PO_STATS(net, IPSTATS_MIB_OUT, skb->len);
902
903 skb->dev = dev;
904 skb->protocol = htons(ETH_P_IP);
905
906 return NF_HOOK_COND(NFPROTO_IPV4, NF_INET_POST_ROUTING,
907 net, sk, skb, NULL, dev,
908 vrf_finish_output,
909 !(IPCB(skb)->flags & IPSKB_REROUTED));
910}
911
912/* set dst on skb to send packet to us via dev_xmit path. Allows
913 * packet to go through device based features such as qdisc, netfilter
914 * hooks and packet sockets with skb->dev set to vrf device.
915 */
916static struct sk_buff *vrf_ip_out_redirect(struct net_device *vrf_dev,
917 struct sk_buff *skb)
918{
919 struct net_vrf *vrf = netdev_priv(vrf_dev);
920 struct dst_entry *dst = NULL;
921 struct rtable *rth;
922
923 rcu_read_lock();
924
925 rth = rcu_dereference(vrf->rth);
926 if (likely(rth)) {
927 dst = &rth->dst;
928 dst_hold(dst);
929 }
930
931 rcu_read_unlock();
932
933 if (unlikely(!dst)) {
934 vrf_tx_error(vrf_dev, skb);
935 return NULL;
936 }
937
938 skb_dst_drop(skb);
939 skb_dst_set(skb, dst);
940
941 return skb;
942}
943
944static int vrf_output_direct_finish(struct net *net, struct sock *sk,
945 struct sk_buff *skb)
946{
947 vrf_finish_direct(skb);
948
949 return vrf_ip_local_out(net, sk, skb);
950}
951
952static int vrf_output_direct(struct net *net, struct sock *sk,
953 struct sk_buff *skb)
954{
955 int err = 1;
956
957 skb->protocol = htons(ETH_P_IP);
958
959 if (!(IPCB(skb)->flags & IPSKB_REROUTED))
960 err = nf_hook(NFPROTO_IPV4, NF_INET_POST_ROUTING, net, sk, skb,
961 NULL, skb->dev, vrf_output_direct_finish);
962
963 if (likely(err == 1))
964 vrf_finish_direct(skb);
965
966 return err;
967}
968
969static int vrf_ip_out_direct_finish(struct net *net, struct sock *sk,
970 struct sk_buff *skb)
971{
972 int err;
973
974 err = vrf_output_direct(net, sk, skb);
975 if (likely(err == 1))
976 err = vrf_ip_local_out(net, sk, skb);
977
978 return err;
979}
980
981static struct sk_buff *vrf_ip_out_direct(struct net_device *vrf_dev,
982 struct sock *sk,
983 struct sk_buff *skb)
984{
985 struct net *net = dev_net(vrf_dev);
986 int err;
987
988 skb->dev = vrf_dev;
989
990 err = nf_hook(NFPROTO_IPV4, NF_INET_LOCAL_OUT, net, sk,
991 skb, NULL, vrf_dev, vrf_ip_out_direct_finish);
992
993 if (likely(err == 1))
994 err = vrf_output_direct(net, sk, skb);
995
996 if (likely(err == 1))
997 return skb;
998
999 return NULL;
1000}
1001
1002static struct sk_buff *vrf_ip_out(struct net_device *vrf_dev,
1003 struct sock *sk,
1004 struct sk_buff *skb)
1005{
1006 /* don't divert multicast or local broadcast */
1007 if (ipv4_is_multicast(ip_hdr(skb)->daddr) ||
1008 ipv4_is_lbcast(ip_hdr(skb)->daddr))
1009 return skb;
1010
1011 if (qdisc_tx_is_default(vrf_dev) ||
1012 IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED)
1013 return vrf_ip_out_direct(vrf_dev, sk, skb);
1014
1015 return vrf_ip_out_redirect(vrf_dev, skb);
1016}
1017
1018/* called with rcu lock held */
1019static struct sk_buff *vrf_l3_out(struct net_device *vrf_dev,
1020 struct sock *sk,
1021 struct sk_buff *skb,
1022 u16 proto)
1023{
1024 switch (proto) {
1025 case AF_INET:
1026 return vrf_ip_out(vrf_dev, sk, skb);
1027 case AF_INET6:
1028 return vrf_ip6_out(vrf_dev, sk, skb);
1029 }
1030
1031 return skb;
1032}
1033
1034/* holding rtnl */
1035static void vrf_rtable_release(struct net_device *dev, struct net_vrf *vrf)
1036{
1037 struct rtable *rth = rtnl_dereference(vrf->rth);
1038 struct net *net = dev_net(dev);
1039 struct dst_entry *dst;
1040
1041 RCU_INIT_POINTER(vrf->rth, NULL);
1042 synchronize_rcu();
1043
1044 /* move dev in dst's to loopback so this VRF device can be deleted
1045 * - based on dst_ifdown
1046 */
1047 if (rth) {
1048 dst = &rth->dst;
1049 dev_put(dst->dev);
1050 dst->dev = net->loopback_dev;
1051 dev_hold(dst->dev);
1052 dst_release(dst);
1053 }
1054}
1055
1056static int vrf_rtable_create(struct net_device *dev)
1057{
1058 struct net_vrf *vrf = netdev_priv(dev);
1059 struct rtable *rth;
1060
1061 if (!fib_new_table(dev_net(dev), vrf->tb_id))
1062 return -ENOMEM;
1063
1064 /* create a dst for routing packets out through a VRF device */
1065 rth = rt_dst_alloc(dev, 0, RTN_UNICAST, 1, 1);
1066 if (!rth)
1067 return -ENOMEM;
1068
1069 rth->dst.output = vrf_output;
1070
1071 rcu_assign_pointer(vrf->rth, rth);
1072
1073 return 0;
1074}
1075
1076/**************************** device handling ********************/
1077
1078/* cycle interface to flush neighbor cache and move routes across tables */
1079static void cycle_netdev(struct net_device *dev,
1080 struct netlink_ext_ack *extack)
1081{
1082 unsigned int flags = dev->flags;
1083 int ret;
1084
1085 if (!netif_running(dev))
1086 return;
1087
1088 ret = dev_change_flags(dev, flags & ~IFF_UP, extack);
1089 if (ret >= 0)
1090 ret = dev_change_flags(dev, flags, extack);
1091
1092 if (ret < 0) {
1093 netdev_err(dev,
1094 "Failed to cycle device %s; route tables might be wrong!\n",
1095 dev->name);
1096 }
1097}
1098
1099static int do_vrf_add_slave(struct net_device *dev, struct net_device *port_dev,
1100 struct netlink_ext_ack *extack)
1101{
1102 int ret;
1103
1104 /* do not allow loopback device to be enslaved to a VRF.
1105 * The vrf device acts as the loopback for the vrf.
1106 */
1107 if (port_dev == dev_net(dev)->loopback_dev) {
1108 NL_SET_ERR_MSG(extack,
1109 "Can not enslave loopback device to a VRF");
1110 return -EOPNOTSUPP;
1111 }
1112
1113 port_dev->priv_flags |= IFF_L3MDEV_SLAVE;
1114 ret = netdev_master_upper_dev_link(port_dev, dev, NULL, NULL, extack);
1115 if (ret < 0)
1116 goto err;
1117
1118 cycle_netdev(port_dev, extack);
1119
1120 return 0;
1121
1122err:
1123 port_dev->priv_flags &= ~IFF_L3MDEV_SLAVE;
1124 return ret;
1125}
1126
1127static int vrf_add_slave(struct net_device *dev, struct net_device *port_dev,
1128 struct netlink_ext_ack *extack)
1129{
1130 if (netif_is_l3_master(port_dev)) {
1131 NL_SET_ERR_MSG(extack,
1132 "Can not enslave an L3 master device to a VRF");
1133 return -EINVAL;
1134 }
1135
1136 if (netif_is_l3_slave(port_dev))
1137 return -EINVAL;
1138
1139 return do_vrf_add_slave(dev, port_dev, extack);
1140}
1141
1142/* inverse of do_vrf_add_slave */
1143static int do_vrf_del_slave(struct net_device *dev, struct net_device *port_dev)
1144{
1145 netdev_upper_dev_unlink(port_dev, dev);
1146 port_dev->priv_flags &= ~IFF_L3MDEV_SLAVE;
1147
1148 cycle_netdev(port_dev, NULL);
1149
1150 return 0;
1151}
1152
1153static int vrf_del_slave(struct net_device *dev, struct net_device *port_dev)
1154{
1155 return do_vrf_del_slave(dev, port_dev);
1156}
1157
1158static void vrf_dev_uninit(struct net_device *dev)
1159{
1160 struct net_vrf *vrf = netdev_priv(dev);
1161
1162 vrf_rtable_release(dev, vrf);
1163 vrf_rt6_release(dev, vrf);
1164
1165 free_percpu(dev->dstats);
1166 dev->dstats = NULL;
1167}
1168
1169static int vrf_dev_init(struct net_device *dev)
1170{
1171 struct net_vrf *vrf = netdev_priv(dev);
1172
1173 dev->dstats = netdev_alloc_pcpu_stats(struct pcpu_dstats);
1174 if (!dev->dstats)
1175 goto out_nomem;
1176
1177 /* create the default dst which points back to us */
1178 if (vrf_rtable_create(dev) != 0)
1179 goto out_stats;
1180
1181 if (vrf_rt6_create(dev) != 0)
1182 goto out_rth;
1183
1184 dev->flags = IFF_MASTER | IFF_NOARP;
1185
1186 /* similarly, oper state is irrelevant; set to up to avoid confusion */
1187 dev->operstate = IF_OPER_UP;
1188 netdev_lockdep_set_classes(dev);
1189 return 0;
1190
1191out_rth:
1192 vrf_rtable_release(dev, vrf);
1193out_stats:
1194 free_percpu(dev->dstats);
1195 dev->dstats = NULL;
1196out_nomem:
1197 return -ENOMEM;
1198}
1199
1200static const struct net_device_ops vrf_netdev_ops = {
1201 .ndo_init = vrf_dev_init,
1202 .ndo_uninit = vrf_dev_uninit,
1203 .ndo_start_xmit = vrf_xmit,
1204 .ndo_set_mac_address = eth_mac_addr,
1205 .ndo_get_stats64 = vrf_get_stats64,
1206 .ndo_add_slave = vrf_add_slave,
1207 .ndo_del_slave = vrf_del_slave,
1208};
1209
1210static u32 vrf_fib_table(const struct net_device *dev)
1211{
1212 struct net_vrf *vrf = netdev_priv(dev);
1213
1214 return vrf->tb_id;
1215}
1216
1217static int vrf_rcv_finish(struct net *net, struct sock *sk, struct sk_buff *skb)
1218{
1219 kfree_skb(skb);
1220 return 0;
1221}
1222
1223static struct sk_buff *vrf_rcv_nfhook(u8 pf, unsigned int hook,
1224 struct sk_buff *skb,
1225 struct net_device *dev)
1226{
1227 struct net *net = dev_net(dev);
1228
1229 if (nf_hook(pf, hook, net, NULL, skb, dev, NULL, vrf_rcv_finish) != 1)
1230 skb = NULL; /* kfree_skb(skb) handled by nf code */
1231
1232 return skb;
1233}
1234
1235static int vrf_prepare_mac_header(struct sk_buff *skb,
1236 struct net_device *vrf_dev, u16 proto)
1237{
1238 struct ethhdr *eth;
1239 int err;
1240
1241 /* in general, we do not know if there is enough space in the head of
1242 * the packet for hosting the mac header.
1243 */
1244 err = skb_cow_head(skb, LL_RESERVED_SPACE(vrf_dev));
1245 if (unlikely(err))
1246 /* no space in the skb head */
1247 return -ENOBUFS;
1248
1249 __skb_push(skb, ETH_HLEN);
1250 eth = (struct ethhdr *)skb->data;
1251
1252 skb_reset_mac_header(skb);
1253
1254 /* we set the ethernet destination and the source addresses to the
1255 * address of the VRF device.
1256 */
1257 ether_addr_copy(eth->h_dest, vrf_dev->dev_addr);
1258 ether_addr_copy(eth->h_source, vrf_dev->dev_addr);
1259 eth->h_proto = htons(proto);
1260
1261 /* the destination address of the Ethernet frame corresponds to the
1262 * address set on the VRF interface; therefore, the packet is intended
1263 * to be processed locally.
1264 */
1265 skb->protocol = eth->h_proto;
1266 skb->pkt_type = PACKET_HOST;
1267
1268 skb_postpush_rcsum(skb, skb->data, ETH_HLEN);
1269
1270 skb_pull_inline(skb, ETH_HLEN);
1271
1272 return 0;
1273}
1274
1275/* prepare and add the mac header to the packet if it was not set previously.
1276 * In this way, packet sniffers such as tcpdump can parse the packet correctly.
1277 * If the mac header was already set, the original mac header is left
1278 * untouched and the function returns immediately.
1279 */
1280static int vrf_add_mac_header_if_unset(struct sk_buff *skb,
1281 struct net_device *vrf_dev,
1282 u16 proto)
1283{
1284 if (skb_mac_header_was_set(skb))
1285 return 0;
1286
1287 return vrf_prepare_mac_header(skb, vrf_dev, proto);
1288}
1289
1290#if IS_ENABLED(CONFIG_IPV6)
1291/* neighbor handling is done with actual device; do not want
1292 * to flip skb->dev for those ndisc packets. This really fails
1293 * for multiple next protocols (e.g., NEXTHDR_HOP). But it is
1294 * a start.
1295 */
1296static bool ipv6_ndisc_frame(const struct sk_buff *skb)
1297{
1298 const struct ipv6hdr *iph = ipv6_hdr(skb);
1299 bool rc = false;
1300
1301 if (iph->nexthdr == NEXTHDR_ICMP) {
1302 const struct icmp6hdr *icmph;
1303 struct icmp6hdr _icmph;
1304
1305 icmph = skb_header_pointer(skb, sizeof(*iph),
1306 sizeof(_icmph), &_icmph);
1307 if (!icmph)
1308 goto out;
1309
1310 switch (icmph->icmp6_type) {
1311 case NDISC_ROUTER_SOLICITATION:
1312 case NDISC_ROUTER_ADVERTISEMENT:
1313 case NDISC_NEIGHBOUR_SOLICITATION:
1314 case NDISC_NEIGHBOUR_ADVERTISEMENT:
1315 case NDISC_REDIRECT:
1316 rc = true;
1317 break;
1318 }
1319 }
1320
1321out:
1322 return rc;
1323}
1324
1325static struct rt6_info *vrf_ip6_route_lookup(struct net *net,
1326 const struct net_device *dev,
1327 struct flowi6 *fl6,
1328 int ifindex,
1329 const struct sk_buff *skb,
1330 int flags)
1331{
1332 struct net_vrf *vrf = netdev_priv(dev);
1333
1334 return ip6_pol_route(net, vrf->fib6_table, ifindex, fl6, skb, flags);
1335}
1336
1337static void vrf_ip6_input_dst(struct sk_buff *skb, struct net_device *vrf_dev,
1338 int ifindex)
1339{
1340 const struct ipv6hdr *iph = ipv6_hdr(skb);
1341 struct flowi6 fl6 = {
1342 .flowi6_iif = ifindex,
1343 .flowi6_mark = skb->mark,
1344 .flowi6_proto = iph->nexthdr,
1345 .daddr = iph->daddr,
1346 .saddr = iph->saddr,
1347 .flowlabel = ip6_flowinfo(iph),
1348 };
1349 struct net *net = dev_net(vrf_dev);
1350 struct rt6_info *rt6;
1351
1352 rt6 = vrf_ip6_route_lookup(net, vrf_dev, &fl6, ifindex, skb,
1353 RT6_LOOKUP_F_HAS_SADDR | RT6_LOOKUP_F_IFACE);
1354 if (unlikely(!rt6))
1355 return;
1356
1357 if (unlikely(&rt6->dst == &net->ipv6.ip6_null_entry->dst))
1358 return;
1359
1360 skb_dst_set(skb, &rt6->dst);
1361}
1362
1363static struct sk_buff *vrf_ip6_rcv(struct net_device *vrf_dev,
1364 struct sk_buff *skb)
1365{
1366 int orig_iif = skb->skb_iif;
1367 bool need_strict = rt6_need_strict(&ipv6_hdr(skb)->daddr);
1368 bool is_ndisc = ipv6_ndisc_frame(skb);
1369
1370 nf_reset_ct(skb);
1371
1372 /* loopback, multicast & non-ND link-local traffic; do not push through
1373 * packet taps again. Reset pkt_type for upper layers to process skb.
1374 * For strict packets with a source LLA, determine the dst using the
1375 * original ifindex.
1376 */
1377 if (skb->pkt_type == PACKET_LOOPBACK || (need_strict && !is_ndisc)) {
1378 skb->dev = vrf_dev;
1379 skb->skb_iif = vrf_dev->ifindex;
1380 IP6CB(skb)->flags |= IP6SKB_L3SLAVE;
1381
1382 if (skb->pkt_type == PACKET_LOOPBACK)
1383 skb->pkt_type = PACKET_HOST;
1384 else if (ipv6_addr_type(&ipv6_hdr(skb)->saddr) & IPV6_ADDR_LINKLOCAL)
1385 vrf_ip6_input_dst(skb, vrf_dev, orig_iif);
1386
1387 goto out;
1388 }
1389
1390 /* if packet is NDISC then keep the ingress interface */
1391 if (!is_ndisc) {
1392 vrf_rx_stats(vrf_dev, skb->len);
1393 skb->dev = vrf_dev;
1394 skb->skb_iif = vrf_dev->ifindex;
1395
1396 if (!list_empty(&vrf_dev->ptype_all)) {
1397 int err;
1398
1399 err = vrf_add_mac_header_if_unset(skb, vrf_dev,
1400 ETH_P_IPV6);
1401 if (likely(!err)) {
1402 skb_push(skb, skb->mac_len);
1403 dev_queue_xmit_nit(skb, vrf_dev);
1404 skb_pull(skb, skb->mac_len);
1405 }
1406 }
1407
1408 IP6CB(skb)->flags |= IP6SKB_L3SLAVE;
1409 }
1410
1411 if (need_strict)
1412 vrf_ip6_input_dst(skb, vrf_dev, orig_iif);
1413
1414 skb = vrf_rcv_nfhook(NFPROTO_IPV6, NF_INET_PRE_ROUTING, skb, vrf_dev);
1415out:
1416 return skb;
1417}
1418
1419#else
1420static struct sk_buff *vrf_ip6_rcv(struct net_device *vrf_dev,
1421 struct sk_buff *skb)
1422{
1423 return skb;
1424}
1425#endif
1426
1427static struct sk_buff *vrf_ip_rcv(struct net_device *vrf_dev,
1428 struct sk_buff *skb)
1429{
1430 skb->dev = vrf_dev;
1431 skb->skb_iif = vrf_dev->ifindex;
1432 IPCB(skb)->flags |= IPSKB_L3SLAVE;
1433
1434 nf_reset_ct(skb);
1435
1436 if (ipv4_is_multicast(ip_hdr(skb)->daddr))
1437 goto out;
1438
1439 /* loopback traffic; do not push through packet taps again.
1440 * Reset pkt_type for upper layers to process skb
1441 */
1442 if (skb->pkt_type == PACKET_LOOPBACK) {
1443 skb->pkt_type = PACKET_HOST;
1444 goto out;
1445 }
1446
1447 vrf_rx_stats(vrf_dev, skb->len);
1448
1449 if (!list_empty(&vrf_dev->ptype_all)) {
1450 int err;
1451
1452 err = vrf_add_mac_header_if_unset(skb, vrf_dev, ETH_P_IP);
1453 if (likely(!err)) {
1454 skb_push(skb, skb->mac_len);
1455 dev_queue_xmit_nit(skb, vrf_dev);
1456 skb_pull(skb, skb->mac_len);
1457 }
1458 }
1459
1460 skb = vrf_rcv_nfhook(NFPROTO_IPV4, NF_INET_PRE_ROUTING, skb, vrf_dev);
1461out:
1462 return skb;
1463}
1464
1465/* called with rcu lock held */
1466static struct sk_buff *vrf_l3_rcv(struct net_device *vrf_dev,
1467 struct sk_buff *skb,
1468 u16 proto)
1469{
1470 switch (proto) {
1471 case AF_INET:
1472 return vrf_ip_rcv(vrf_dev, skb);
1473 case AF_INET6:
1474 return vrf_ip6_rcv(vrf_dev, skb);
1475 }
1476
1477 return skb;
1478}
1479
1480#if IS_ENABLED(CONFIG_IPV6)
1481/* send to link-local or multicast address via interface enslaved to
1482 * VRF device. Force lookup to VRF table without changing flow struct
1483 * Note: Caller to this function must hold rcu_read_lock() and no refcnt
1484 * is taken on the dst by this function.
1485 */
1486static struct dst_entry *vrf_link_scope_lookup(const struct net_device *dev,
1487 struct flowi6 *fl6)
1488{
1489 struct net *net = dev_net(dev);
1490 int flags = RT6_LOOKUP_F_IFACE | RT6_LOOKUP_F_DST_NOREF;
1491 struct dst_entry *dst = NULL;
1492 struct rt6_info *rt;
1493
1494 /* VRF device does not have a link-local address and
1495 * sending packets to link-local or mcast addresses over
1496 * a VRF device does not make sense
1497 */
1498 if (fl6->flowi6_oif == dev->ifindex) {
1499 dst = &net->ipv6.ip6_null_entry->dst;
1500 return dst;
1501 }
1502
1503 if (!ipv6_addr_any(&fl6->saddr))
1504 flags |= RT6_LOOKUP_F_HAS_SADDR;
1505
1506 rt = vrf_ip6_route_lookup(net, dev, fl6, fl6->flowi6_oif, NULL, flags);
1507 if (rt)
1508 dst = &rt->dst;
1509
1510 return dst;
1511}
1512#endif
1513
1514static const struct l3mdev_ops vrf_l3mdev_ops = {
1515 .l3mdev_fib_table = vrf_fib_table,
1516 .l3mdev_l3_rcv = vrf_l3_rcv,
1517 .l3mdev_l3_out = vrf_l3_out,
1518#if IS_ENABLED(CONFIG_IPV6)
1519 .l3mdev_link_scope_lookup = vrf_link_scope_lookup,
1520#endif
1521};
1522
1523static void vrf_get_drvinfo(struct net_device *dev,
1524 struct ethtool_drvinfo *info)
1525{
1526 strlcpy(info->driver, DRV_NAME, sizeof(info->driver));
1527 strlcpy(info->version, DRV_VERSION, sizeof(info->version));
1528}
1529
1530static const struct ethtool_ops vrf_ethtool_ops = {
1531 .get_drvinfo = vrf_get_drvinfo,
1532};
1533
1534static inline size_t vrf_fib_rule_nl_size(void)
1535{
1536 size_t sz;
1537
1538 sz = NLMSG_ALIGN(sizeof(struct fib_rule_hdr));
1539 sz += nla_total_size(sizeof(u8)); /* FRA_L3MDEV */
1540 sz += nla_total_size(sizeof(u32)); /* FRA_PRIORITY */
1541 sz += nla_total_size(sizeof(u8)); /* FRA_PROTOCOL */
1542
1543 return sz;
1544}
1545
1546static int vrf_fib_rule(const struct net_device *dev, __u8 family, bool add_it)
1547{
1548 struct fib_rule_hdr *frh;
1549 struct nlmsghdr *nlh;
1550 struct sk_buff *skb;
1551 int err;
1552
1553 if ((family == AF_INET6 || family == RTNL_FAMILY_IP6MR) &&
1554 !ipv6_mod_enabled())
1555 return 0;
1556
1557 skb = nlmsg_new(vrf_fib_rule_nl_size(), GFP_KERNEL);
1558 if (!skb)
1559 return -ENOMEM;
1560
1561 nlh = nlmsg_put(skb, 0, 0, 0, sizeof(*frh), 0);
1562 if (!nlh)
1563 goto nla_put_failure;
1564
1565 /* rule only needs to appear once */
1566 nlh->nlmsg_flags |= NLM_F_EXCL;
1567
1568 frh = nlmsg_data(nlh);
1569 memset(frh, 0, sizeof(*frh));
1570 frh->family = family;
1571 frh->action = FR_ACT_TO_TBL;
1572
1573 if (nla_put_u8(skb, FRA_PROTOCOL, RTPROT_KERNEL))
1574 goto nla_put_failure;
1575
1576 if (nla_put_u8(skb, FRA_L3MDEV, 1))
1577 goto nla_put_failure;
1578
1579 if (nla_put_u32(skb, FRA_PRIORITY, FIB_RULE_PREF))
1580 goto nla_put_failure;
1581
1582 nlmsg_end(skb, nlh);
1583
1584 /* fib_nl_{new,del}rule handling looks for net from skb->sk */
1585 skb->sk = dev_net(dev)->rtnl;
1586 if (add_it) {
1587 err = fib_nl_newrule(skb, nlh, NULL);
1588 if (err == -EEXIST)
1589 err = 0;
1590 } else {
1591 err = fib_nl_delrule(skb, nlh, NULL);
1592 if (err == -ENOENT)
1593 err = 0;
1594 }
1595 nlmsg_free(skb);
1596
1597 return err;
1598
1599nla_put_failure:
1600 nlmsg_free(skb);
1601
1602 return -EMSGSIZE;
1603}
1604
1605static int vrf_add_fib_rules(const struct net_device *dev)
1606{
1607 int err;
1608
1609 err = vrf_fib_rule(dev, AF_INET, true);
1610 if (err < 0)
1611 goto out_err;
1612
1613 err = vrf_fib_rule(dev, AF_INET6, true);
1614 if (err < 0)
1615 goto ipv6_err;
1616
1617#if IS_ENABLED(CONFIG_IP_MROUTE_MULTIPLE_TABLES)
1618 err = vrf_fib_rule(dev, RTNL_FAMILY_IPMR, true);
1619 if (err < 0)
1620 goto ipmr_err;
1621#endif
1622
1623#if IS_ENABLED(CONFIG_IPV6_MROUTE_MULTIPLE_TABLES)
1624 err = vrf_fib_rule(dev, RTNL_FAMILY_IP6MR, true);
1625 if (err < 0)
1626 goto ip6mr_err;
1627#endif
1628
1629 return 0;
1630
1631#if IS_ENABLED(CONFIG_IPV6_MROUTE_MULTIPLE_TABLES)
1632ip6mr_err:
1633 vrf_fib_rule(dev, RTNL_FAMILY_IPMR, false);
1634#endif
1635
1636#if IS_ENABLED(CONFIG_IP_MROUTE_MULTIPLE_TABLES)
1637ipmr_err:
1638 vrf_fib_rule(dev, AF_INET6, false);
1639#endif
1640
1641ipv6_err:
1642 vrf_fib_rule(dev, AF_INET, false);
1643
1644out_err:
1645 netdev_err(dev, "Failed to add FIB rules.\n");
1646 return err;
1647}
1648
1649static void vrf_setup(struct net_device *dev)
1650{
1651 ether_setup(dev);
1652
1653 /* Initialize the device structure. */
1654 dev->netdev_ops = &vrf_netdev_ops;
1655 dev->l3mdev_ops = &vrf_l3mdev_ops;
1656 dev->ethtool_ops = &vrf_ethtool_ops;
1657 dev->needs_free_netdev = true;
1658
1659 /* Fill in device structure with ethernet-generic values. */
1660 eth_hw_addr_random(dev);
1661
1662 /* don't acquire vrf device's netif_tx_lock when transmitting */
1663 dev->features |= NETIF_F_LLTX;
1664
1665 /* don't allow vrf devices to change network namespaces. */
1666 dev->features |= NETIF_F_NETNS_LOCAL;
1667
1668 /* does not make sense for a VLAN to be added to a vrf device */
1669 dev->features |= NETIF_F_VLAN_CHALLENGED;
1670
1671 /* enable offload features */
1672 dev->features |= NETIF_F_GSO_SOFTWARE;
1673 dev->features |= NETIF_F_RXCSUM | NETIF_F_HW_CSUM | NETIF_F_SCTP_CRC;
1674 dev->features |= NETIF_F_SG | NETIF_F_FRAGLIST | NETIF_F_HIGHDMA;
1675
1676 dev->hw_features = dev->features;
1677 dev->hw_enc_features = dev->features;
1678
1679 /* default to no qdisc; user can add if desired */
1680 dev->priv_flags |= IFF_NO_QUEUE;
1681 dev->priv_flags |= IFF_NO_RX_HANDLER;
1682 dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1683
1684 /* VRF devices do not care about MTU, but if the MTU is set
1685 * too low then the ipv4 and ipv6 protocols are disabled
1686 * which breaks networking.
1687 */
1688 dev->min_mtu = IPV6_MIN_MTU;
1689 dev->max_mtu = IP6_MAX_MTU;
1690 dev->mtu = dev->max_mtu;
1691}
1692
1693static int vrf_validate(struct nlattr *tb[], struct nlattr *data[],
1694 struct netlink_ext_ack *extack)
1695{
1696 if (tb[IFLA_ADDRESS]) {
1697 if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN) {
1698 NL_SET_ERR_MSG(extack, "Invalid hardware address");
1699 return -EINVAL;
1700 }
1701 if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS]))) {
1702 NL_SET_ERR_MSG(extack, "Invalid hardware address");
1703 return -EADDRNOTAVAIL;
1704 }
1705 }
1706 return 0;
1707}
1708
1709static void vrf_dellink(struct net_device *dev, struct list_head *head)
1710{
1711 struct net_device *port_dev;
1712 struct list_head *iter;
1713
1714 netdev_for_each_lower_dev(dev, port_dev, iter)
1715 vrf_del_slave(dev, port_dev);
1716
1717 vrf_map_unregister_dev(dev);
1718
1719 unregister_netdevice_queue(dev, head);
1720}
1721
1722static int vrf_newlink(struct net *src_net, struct net_device *dev,
1723 struct nlattr *tb[], struct nlattr *data[],
1724 struct netlink_ext_ack *extack)
1725{
1726 struct net_vrf *vrf = netdev_priv(dev);
1727 struct netns_vrf *nn_vrf;
1728 bool *add_fib_rules;
1729 struct net *net;
1730 int err;
1731
1732 if (!data || !data[IFLA_VRF_TABLE]) {
1733 NL_SET_ERR_MSG(extack, "VRF table id is missing");
1734 return -EINVAL;
1735 }
1736
1737 vrf->tb_id = nla_get_u32(data[IFLA_VRF_TABLE]);
1738 if (vrf->tb_id == RT_TABLE_UNSPEC) {
1739 NL_SET_ERR_MSG_ATTR(extack, data[IFLA_VRF_TABLE],
1740 "Invalid VRF table id");
1741 return -EINVAL;
1742 }
1743
1744 dev->priv_flags |= IFF_L3MDEV_MASTER;
1745
1746 err = register_netdevice(dev);
1747 if (err)
1748 goto out;
1749
1750 /* mapping between table_id and vrf;
1751 * note: such binding could not be done in the dev init function
1752 * because dev->ifindex id is not available yet.
1753 */
1754 vrf->ifindex = dev->ifindex;
1755
1756 err = vrf_map_register_dev(dev, extack);
1757 if (err) {
1758 unregister_netdevice(dev);
1759 goto out;
1760 }
1761
1762 net = dev_net(dev);
1763 nn_vrf = net_generic(net, vrf_net_id);
1764
1765 add_fib_rules = &nn_vrf->add_fib_rules;
1766 if (*add_fib_rules) {
1767 err = vrf_add_fib_rules(dev);
1768 if (err) {
1769 vrf_map_unregister_dev(dev);
1770 unregister_netdevice(dev);
1771 goto out;
1772 }
1773 *add_fib_rules = false;
1774 }
1775
1776out:
1777 return err;
1778}
1779
1780static size_t vrf_nl_getsize(const struct net_device *dev)
1781{
1782 return nla_total_size(sizeof(u32)); /* IFLA_VRF_TABLE */
1783}
1784
1785static int vrf_fillinfo(struct sk_buff *skb,
1786 const struct net_device *dev)
1787{
1788 struct net_vrf *vrf = netdev_priv(dev);
1789
1790 return nla_put_u32(skb, IFLA_VRF_TABLE, vrf->tb_id);
1791}
1792
1793static size_t vrf_get_slave_size(const struct net_device *bond_dev,
1794 const struct net_device *slave_dev)
1795{
1796 return nla_total_size(sizeof(u32)); /* IFLA_VRF_PORT_TABLE */
1797}
1798
1799static int vrf_fill_slave_info(struct sk_buff *skb,
1800 const struct net_device *vrf_dev,
1801 const struct net_device *slave_dev)
1802{
1803 struct net_vrf *vrf = netdev_priv(vrf_dev);
1804
1805 if (nla_put_u32(skb, IFLA_VRF_PORT_TABLE, vrf->tb_id))
1806 return -EMSGSIZE;
1807
1808 return 0;
1809}
1810
1811static const struct nla_policy vrf_nl_policy[IFLA_VRF_MAX + 1] = {
1812 [IFLA_VRF_TABLE] = { .type = NLA_U32 },
1813};
1814
1815static struct rtnl_link_ops vrf_link_ops __read_mostly = {
1816 .kind = DRV_NAME,
1817 .priv_size = sizeof(struct net_vrf),
1818
1819 .get_size = vrf_nl_getsize,
1820 .policy = vrf_nl_policy,
1821 .validate = vrf_validate,
1822 .fill_info = vrf_fillinfo,
1823
1824 .get_slave_size = vrf_get_slave_size,
1825 .fill_slave_info = vrf_fill_slave_info,
1826
1827 .newlink = vrf_newlink,
1828 .dellink = vrf_dellink,
1829 .setup = vrf_setup,
1830 .maxtype = IFLA_VRF_MAX,
1831};
1832
1833static int vrf_device_event(struct notifier_block *unused,
1834 unsigned long event, void *ptr)
1835{
1836 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
1837
1838 /* only care about unregister events to drop slave references */
1839 if (event == NETDEV_UNREGISTER) {
1840 struct net_device *vrf_dev;
1841
1842 if (!netif_is_l3_slave(dev))
1843 goto out;
1844
1845 vrf_dev = netdev_master_upper_dev_get(dev);
1846 vrf_del_slave(vrf_dev, dev);
1847 }
1848out:
1849 return NOTIFY_DONE;
1850}
1851
1852static struct notifier_block vrf_notifier_block __read_mostly = {
1853 .notifier_call = vrf_device_event,
1854};
1855
1856static int vrf_map_init(struct vrf_map *vmap)
1857{
1858 spin_lock_init(&vmap->vmap_lock);
1859 hash_init(vmap->ht);
1860
1861 vmap->strict_mode = false;
1862
1863 return 0;
1864}
1865
1866#ifdef CONFIG_SYSCTL
1867static bool vrf_strict_mode(struct vrf_map *vmap)
1868{
1869 bool strict_mode;
1870
1871 vrf_map_lock(vmap);
1872 strict_mode = vmap->strict_mode;
1873 vrf_map_unlock(vmap);
1874
1875 return strict_mode;
1876}
1877
1878static int vrf_strict_mode_change(struct vrf_map *vmap, bool new_mode)
1879{
1880 bool *cur_mode;
1881 int res = 0;
1882
1883 vrf_map_lock(vmap);
1884
1885 cur_mode = &vmap->strict_mode;
1886 if (*cur_mode == new_mode)
1887 goto unlock;
1888
1889 if (*cur_mode) {
1890 /* disable strict mode */
1891 *cur_mode = false;
1892 } else {
1893 if (vmap->shared_tables) {
1894 /* we cannot allow strict_mode because there are some
1895 * vrfs that share one or more tables.
1896 */
1897 res = -EBUSY;
1898 goto unlock;
1899 }
1900
1901 /* no tables are shared among vrfs, so we can go back
1902 * to 1:1 association between a vrf with its table.
1903 */
1904 *cur_mode = true;
1905 }
1906
1907unlock:
1908 vrf_map_unlock(vmap);
1909
1910 return res;
1911}
1912
1913static int vrf_shared_table_handler(struct ctl_table *table, int write,
1914 void *buffer, size_t *lenp, loff_t *ppos)
1915{
1916 struct net *net = (struct net *)table->extra1;
1917 struct vrf_map *vmap = netns_vrf_map(net);
1918 int proc_strict_mode = 0;
1919 struct ctl_table tmp = {
1920 .procname = table->procname,
1921 .data = &proc_strict_mode,
1922 .maxlen = sizeof(int),
1923 .mode = table->mode,
1924 .extra1 = SYSCTL_ZERO,
1925 .extra2 = SYSCTL_ONE,
1926 };
1927 int ret;
1928
1929 if (!write)
1930 proc_strict_mode = vrf_strict_mode(vmap);
1931
1932 ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
1933
1934 if (write && ret == 0)
1935 ret = vrf_strict_mode_change(vmap, (bool)proc_strict_mode);
1936
1937 return ret;
1938}
1939
1940static const struct ctl_table vrf_table[] = {
1941 {
1942 .procname = "strict_mode",
1943 .data = NULL,
1944 .maxlen = sizeof(int),
1945 .mode = 0644,
1946 .proc_handler = vrf_shared_table_handler,
1947 /* set by the vrf_netns_init */
1948 .extra1 = NULL,
1949 },
1950 { },
1951};
1952
1953static int vrf_netns_init_sysctl(struct net *net, struct netns_vrf *nn_vrf)
1954{
1955 struct ctl_table *table;
1956
1957 table = kmemdup(vrf_table, sizeof(vrf_table), GFP_KERNEL);
1958 if (!table)
1959 return -ENOMEM;
1960
1961 /* init the extra1 parameter with the reference to current netns */
1962 table[0].extra1 = net;
1963
1964 nn_vrf->ctl_hdr = register_net_sysctl(net, "net/vrf", table);
1965 if (!nn_vrf->ctl_hdr) {
1966 kfree(table);
1967 return -ENOMEM;
1968 }
1969
1970 return 0;
1971}
1972
1973static void vrf_netns_exit_sysctl(struct net *net)
1974{
1975 struct netns_vrf *nn_vrf = net_generic(net, vrf_net_id);
1976 struct ctl_table *table;
1977
1978 table = nn_vrf->ctl_hdr->ctl_table_arg;
1979 unregister_net_sysctl_table(nn_vrf->ctl_hdr);
1980 kfree(table);
1981}
1982#else
1983static int vrf_netns_init_sysctl(struct net *net, struct netns_vrf *nn_vrf)
1984{
1985 return 0;
1986}
1987
1988static void vrf_netns_exit_sysctl(struct net *net)
1989{
1990}
1991#endif
1992
1993/* Initialize per network namespace state */
1994static int __net_init vrf_netns_init(struct net *net)
1995{
1996 struct netns_vrf *nn_vrf = net_generic(net, vrf_net_id);
1997
1998 nn_vrf->add_fib_rules = true;
1999 vrf_map_init(&nn_vrf->vmap);
2000
2001 return vrf_netns_init_sysctl(net, nn_vrf);
2002}
2003
2004static void __net_exit vrf_netns_exit(struct net *net)
2005{
2006 vrf_netns_exit_sysctl(net);
2007}
2008
2009static struct pernet_operations vrf_net_ops __net_initdata = {
2010 .init = vrf_netns_init,
2011 .exit = vrf_netns_exit,
2012 .id = &vrf_net_id,
2013 .size = sizeof(struct netns_vrf),
2014};
2015
2016static int __init vrf_init_module(void)
2017{
2018 int rc;
2019
2020 register_netdevice_notifier(&vrf_notifier_block);
2021
2022 rc = register_pernet_subsys(&vrf_net_ops);
2023 if (rc < 0)
2024 goto error;
2025
2026 rc = l3mdev_table_lookup_register(L3MDEV_TYPE_VRF,
2027 vrf_ifindex_lookup_by_table_id);
2028 if (rc < 0)
2029 goto unreg_pernet;
2030
2031 rc = rtnl_link_register(&vrf_link_ops);
2032 if (rc < 0)
2033 goto table_lookup_unreg;
2034
2035 return 0;
2036
2037table_lookup_unreg:
2038 l3mdev_table_lookup_unregister(L3MDEV_TYPE_VRF,
2039 vrf_ifindex_lookup_by_table_id);
2040
2041unreg_pernet:
2042 unregister_pernet_subsys(&vrf_net_ops);
2043
2044error:
2045 unregister_netdevice_notifier(&vrf_notifier_block);
2046 return rc;
2047}
2048
2049module_init(vrf_init_module);
2050MODULE_AUTHOR("Shrijeet Mukherjee, David Ahern");
2051MODULE_DESCRIPTION("Device driver to instantiate VRF domains");
2052MODULE_LICENSE("GPL");
2053MODULE_ALIAS_RTNL_LINK(DRV_NAME);
2054MODULE_VERSION(DRV_VERSION);