powerpc/fadump: Do not allow hot-remove memory from fadump reserved area.
[linux/fpc-iii.git] / drivers / net / vrf.c
blobf93547f257fbbe22ccb8da8d7eca6c6230b28d40
1 /*
2 * vrf.c: device driver to encapsulate a VRF space
4 * Copyright (c) 2015 Cumulus Networks. All rights reserved.
5 * Copyright (c) 2015 Shrijeet Mukherjee <shm@cumulusnetworks.com>
6 * Copyright (c) 2015 David Ahern <dsa@cumulusnetworks.com>
8 * Based on dummy, team and ipvlan drivers
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
16 #include <linux/module.h>
17 #include <linux/kernel.h>
18 #include <linux/netdevice.h>
19 #include <linux/etherdevice.h>
20 #include <linux/ip.h>
21 #include <linux/init.h>
22 #include <linux/moduleparam.h>
23 #include <linux/netfilter.h>
24 #include <linux/rtnetlink.h>
25 #include <net/rtnetlink.h>
26 #include <linux/u64_stats_sync.h>
27 #include <linux/hashtable.h>
29 #include <linux/inetdevice.h>
30 #include <net/arp.h>
31 #include <net/ip.h>
32 #include <net/ip_fib.h>
33 #include <net/ip6_fib.h>
34 #include <net/ip6_route.h>
35 #include <net/route.h>
36 #include <net/addrconf.h>
37 #include <net/l3mdev.h>
38 #include <net/fib_rules.h>
39 #include <net/netns/generic.h>
41 #define DRV_NAME "vrf"
42 #define DRV_VERSION "1.0"
44 #define FIB_RULE_PREF 1000 /* default preference for FIB rules */
46 static unsigned int vrf_net_id;
48 struct net_vrf {
49 struct rtable __rcu *rth;
50 struct rt6_info __rcu *rt6;
51 #if IS_ENABLED(CONFIG_IPV6)
52 struct fib6_table *fib6_table;
53 #endif
54 u32 tb_id;
57 struct pcpu_dstats {
58 u64 tx_pkts;
59 u64 tx_bytes;
60 u64 tx_drps;
61 u64 rx_pkts;
62 u64 rx_bytes;
63 u64 rx_drps;
64 struct u64_stats_sync syncp;
67 static void vrf_rx_stats(struct net_device *dev, int len)
69 struct pcpu_dstats *dstats = this_cpu_ptr(dev->dstats);
71 u64_stats_update_begin(&dstats->syncp);
72 dstats->rx_pkts++;
73 dstats->rx_bytes += len;
74 u64_stats_update_end(&dstats->syncp);
77 static void vrf_tx_error(struct net_device *vrf_dev, struct sk_buff *skb)
79 vrf_dev->stats.tx_errors++;
80 kfree_skb(skb);
83 static void vrf_get_stats64(struct net_device *dev,
84 struct rtnl_link_stats64 *stats)
86 int i;
88 for_each_possible_cpu(i) {
89 const struct pcpu_dstats *dstats;
90 u64 tbytes, tpkts, tdrops, rbytes, rpkts;
91 unsigned int start;
93 dstats = per_cpu_ptr(dev->dstats, i);
94 do {
95 start = u64_stats_fetch_begin_irq(&dstats->syncp);
96 tbytes = dstats->tx_bytes;
97 tpkts = dstats->tx_pkts;
98 tdrops = dstats->tx_drps;
99 rbytes = dstats->rx_bytes;
100 rpkts = dstats->rx_pkts;
101 } while (u64_stats_fetch_retry_irq(&dstats->syncp, start));
102 stats->tx_bytes += tbytes;
103 stats->tx_packets += tpkts;
104 stats->tx_dropped += tdrops;
105 stats->rx_bytes += rbytes;
106 stats->rx_packets += rpkts;
110 /* by default VRF devices do not have a qdisc and are expected
111 * to be created with only a single queue.
113 static bool qdisc_tx_is_default(const struct net_device *dev)
115 struct netdev_queue *txq;
116 struct Qdisc *qdisc;
118 if (dev->num_tx_queues > 1)
119 return false;
121 txq = netdev_get_tx_queue(dev, 0);
122 qdisc = rcu_access_pointer(txq->qdisc);
124 return !qdisc->enqueue;
127 /* Local traffic destined to local address. Reinsert the packet to rx
128 * path, similar to loopback handling.
130 static int vrf_local_xmit(struct sk_buff *skb, struct net_device *dev,
131 struct dst_entry *dst)
133 int len = skb->len;
135 skb_orphan(skb);
137 skb_dst_set(skb, dst);
139 /* set pkt_type to avoid skb hitting packet taps twice -
140 * once on Tx and again in Rx processing
142 skb->pkt_type = PACKET_LOOPBACK;
144 skb->protocol = eth_type_trans(skb, dev);
146 if (likely(netif_rx(skb) == NET_RX_SUCCESS))
147 vrf_rx_stats(dev, len);
148 else
149 this_cpu_inc(dev->dstats->rx_drps);
151 return NETDEV_TX_OK;
154 #if IS_ENABLED(CONFIG_IPV6)
155 static int vrf_ip6_local_out(struct net *net, struct sock *sk,
156 struct sk_buff *skb)
158 int err;
160 err = nf_hook(NFPROTO_IPV6, NF_INET_LOCAL_OUT, net,
161 sk, skb, NULL, skb_dst(skb)->dev, dst_output);
163 if (likely(err == 1))
164 err = dst_output(net, sk, skb);
166 return err;
169 static netdev_tx_t vrf_process_v6_outbound(struct sk_buff *skb,
170 struct net_device *dev)
172 const struct ipv6hdr *iph = ipv6_hdr(skb);
173 struct net *net = dev_net(skb->dev);
174 struct flowi6 fl6 = {
175 /* needed to match OIF rule */
176 .flowi6_oif = dev->ifindex,
177 .flowi6_iif = LOOPBACK_IFINDEX,
178 .daddr = iph->daddr,
179 .saddr = iph->saddr,
180 .flowlabel = ip6_flowinfo(iph),
181 .flowi6_mark = skb->mark,
182 .flowi6_proto = iph->nexthdr,
183 .flowi6_flags = FLOWI_FLAG_SKIP_NH_OIF,
185 int ret = NET_XMIT_DROP;
186 struct dst_entry *dst;
187 struct dst_entry *dst_null = &net->ipv6.ip6_null_entry->dst;
189 dst = ip6_route_output(net, NULL, &fl6);
190 if (dst == dst_null)
191 goto err;
193 skb_dst_drop(skb);
195 /* if dst.dev is loopback or the VRF device again this is locally
196 * originated traffic destined to a local address. Short circuit
197 * to Rx path
199 if (dst->dev == dev)
200 return vrf_local_xmit(skb, dev, dst);
202 skb_dst_set(skb, dst);
204 /* strip the ethernet header added for pass through VRF device */
205 __skb_pull(skb, skb_network_offset(skb));
207 ret = vrf_ip6_local_out(net, skb->sk, skb);
208 if (unlikely(net_xmit_eval(ret)))
209 dev->stats.tx_errors++;
210 else
211 ret = NET_XMIT_SUCCESS;
213 return ret;
214 err:
215 vrf_tx_error(dev, skb);
216 return NET_XMIT_DROP;
218 #else
219 static netdev_tx_t vrf_process_v6_outbound(struct sk_buff *skb,
220 struct net_device *dev)
222 vrf_tx_error(dev, skb);
223 return NET_XMIT_DROP;
225 #endif
227 /* based on ip_local_out; can't use it b/c the dst is switched pointing to us */
228 static int vrf_ip_local_out(struct net *net, struct sock *sk,
229 struct sk_buff *skb)
231 int err;
233 err = nf_hook(NFPROTO_IPV4, NF_INET_LOCAL_OUT, net, sk,
234 skb, NULL, skb_dst(skb)->dev, dst_output);
235 if (likely(err == 1))
236 err = dst_output(net, sk, skb);
238 return err;
241 static netdev_tx_t vrf_process_v4_outbound(struct sk_buff *skb,
242 struct net_device *vrf_dev)
244 struct iphdr *ip4h = ip_hdr(skb);
245 int ret = NET_XMIT_DROP;
246 struct flowi4 fl4 = {
247 /* needed to match OIF rule */
248 .flowi4_oif = vrf_dev->ifindex,
249 .flowi4_iif = LOOPBACK_IFINDEX,
250 .flowi4_tos = RT_TOS(ip4h->tos),
251 .flowi4_flags = FLOWI_FLAG_ANYSRC | FLOWI_FLAG_SKIP_NH_OIF,
252 .flowi4_proto = ip4h->protocol,
253 .daddr = ip4h->daddr,
254 .saddr = ip4h->saddr,
256 struct net *net = dev_net(vrf_dev);
257 struct rtable *rt;
259 rt = ip_route_output_flow(net, &fl4, NULL);
260 if (IS_ERR(rt))
261 goto err;
263 skb_dst_drop(skb);
265 /* if dst.dev is loopback or the VRF device again this is locally
266 * originated traffic destined to a local address. Short circuit
267 * to Rx path
269 if (rt->dst.dev == vrf_dev)
270 return vrf_local_xmit(skb, vrf_dev, &rt->dst);
272 skb_dst_set(skb, &rt->dst);
274 /* strip the ethernet header added for pass through VRF device */
275 __skb_pull(skb, skb_network_offset(skb));
277 if (!ip4h->saddr) {
278 ip4h->saddr = inet_select_addr(skb_dst(skb)->dev, 0,
279 RT_SCOPE_LINK);
282 ret = vrf_ip_local_out(dev_net(skb_dst(skb)->dev), skb->sk, skb);
283 if (unlikely(net_xmit_eval(ret)))
284 vrf_dev->stats.tx_errors++;
285 else
286 ret = NET_XMIT_SUCCESS;
288 out:
289 return ret;
290 err:
291 vrf_tx_error(vrf_dev, skb);
292 goto out;
295 static netdev_tx_t is_ip_tx_frame(struct sk_buff *skb, struct net_device *dev)
297 switch (skb->protocol) {
298 case htons(ETH_P_IP):
299 return vrf_process_v4_outbound(skb, dev);
300 case htons(ETH_P_IPV6):
301 return vrf_process_v6_outbound(skb, dev);
302 default:
303 vrf_tx_error(dev, skb);
304 return NET_XMIT_DROP;
308 static netdev_tx_t vrf_xmit(struct sk_buff *skb, struct net_device *dev)
310 int len = skb->len;
311 netdev_tx_t ret = is_ip_tx_frame(skb, dev);
313 if (likely(ret == NET_XMIT_SUCCESS || ret == NET_XMIT_CN)) {
314 struct pcpu_dstats *dstats = this_cpu_ptr(dev->dstats);
316 u64_stats_update_begin(&dstats->syncp);
317 dstats->tx_pkts++;
318 dstats->tx_bytes += len;
319 u64_stats_update_end(&dstats->syncp);
320 } else {
321 this_cpu_inc(dev->dstats->tx_drps);
324 return ret;
327 static int vrf_finish_direct(struct net *net, struct sock *sk,
328 struct sk_buff *skb)
330 struct net_device *vrf_dev = skb->dev;
332 if (!list_empty(&vrf_dev->ptype_all) &&
333 likely(skb_headroom(skb) >= ETH_HLEN)) {
334 struct ethhdr *eth = skb_push(skb, ETH_HLEN);
336 ether_addr_copy(eth->h_source, vrf_dev->dev_addr);
337 eth_zero_addr(eth->h_dest);
338 eth->h_proto = skb->protocol;
340 rcu_read_lock_bh();
341 dev_queue_xmit_nit(skb, vrf_dev);
342 rcu_read_unlock_bh();
344 skb_pull(skb, ETH_HLEN);
347 return 1;
350 #if IS_ENABLED(CONFIG_IPV6)
351 /* modelled after ip6_finish_output2 */
352 static int vrf_finish_output6(struct net *net, struct sock *sk,
353 struct sk_buff *skb)
355 struct dst_entry *dst = skb_dst(skb);
356 struct net_device *dev = dst->dev;
357 struct neighbour *neigh;
358 struct in6_addr *nexthop;
359 int ret;
361 nf_reset(skb);
363 skb->protocol = htons(ETH_P_IPV6);
364 skb->dev = dev;
366 rcu_read_lock_bh();
367 nexthop = rt6_nexthop((struct rt6_info *)dst, &ipv6_hdr(skb)->daddr);
368 neigh = __ipv6_neigh_lookup_noref(dst->dev, nexthop);
369 if (unlikely(!neigh))
370 neigh = __neigh_create(&nd_tbl, nexthop, dst->dev, false);
371 if (!IS_ERR(neigh)) {
372 sock_confirm_neigh(skb, neigh);
373 ret = neigh_output(neigh, skb);
374 rcu_read_unlock_bh();
375 return ret;
377 rcu_read_unlock_bh();
379 IP6_INC_STATS(dev_net(dst->dev),
380 ip6_dst_idev(dst), IPSTATS_MIB_OUTNOROUTES);
381 kfree_skb(skb);
382 return -EINVAL;
385 /* modelled after ip6_output */
386 static int vrf_output6(struct net *net, struct sock *sk, struct sk_buff *skb)
388 return NF_HOOK_COND(NFPROTO_IPV6, NF_INET_POST_ROUTING,
389 net, sk, skb, NULL, skb_dst(skb)->dev,
390 vrf_finish_output6,
391 !(IP6CB(skb)->flags & IP6SKB_REROUTED));
394 /* set dst on skb to send packet to us via dev_xmit path. Allows
395 * packet to go through device based features such as qdisc, netfilter
396 * hooks and packet sockets with skb->dev set to vrf device.
398 static struct sk_buff *vrf_ip6_out_redirect(struct net_device *vrf_dev,
399 struct sk_buff *skb)
401 struct net_vrf *vrf = netdev_priv(vrf_dev);
402 struct dst_entry *dst = NULL;
403 struct rt6_info *rt6;
405 rcu_read_lock();
407 rt6 = rcu_dereference(vrf->rt6);
408 if (likely(rt6)) {
409 dst = &rt6->dst;
410 dst_hold(dst);
413 rcu_read_unlock();
415 if (unlikely(!dst)) {
416 vrf_tx_error(vrf_dev, skb);
417 return NULL;
420 skb_dst_drop(skb);
421 skb_dst_set(skb, dst);
423 return skb;
426 static int vrf_output6_direct(struct net *net, struct sock *sk,
427 struct sk_buff *skb)
429 skb->protocol = htons(ETH_P_IPV6);
431 return NF_HOOK_COND(NFPROTO_IPV6, NF_INET_POST_ROUTING,
432 net, sk, skb, NULL, skb->dev,
433 vrf_finish_direct,
434 !(IPCB(skb)->flags & IPSKB_REROUTED));
437 static struct sk_buff *vrf_ip6_out_direct(struct net_device *vrf_dev,
438 struct sock *sk,
439 struct sk_buff *skb)
441 struct net *net = dev_net(vrf_dev);
442 int err;
444 skb->dev = vrf_dev;
446 err = nf_hook(NFPROTO_IPV6, NF_INET_LOCAL_OUT, net, sk,
447 skb, NULL, vrf_dev, vrf_output6_direct);
449 if (likely(err == 1))
450 err = vrf_output6_direct(net, sk, skb);
452 /* reset skb device */
453 if (likely(err == 1))
454 nf_reset(skb);
455 else
456 skb = NULL;
458 return skb;
461 static struct sk_buff *vrf_ip6_out(struct net_device *vrf_dev,
462 struct sock *sk,
463 struct sk_buff *skb)
465 /* don't divert link scope packets */
466 if (rt6_need_strict(&ipv6_hdr(skb)->daddr))
467 return skb;
469 if (qdisc_tx_is_default(vrf_dev))
470 return vrf_ip6_out_direct(vrf_dev, sk, skb);
472 return vrf_ip6_out_redirect(vrf_dev, skb);
475 /* holding rtnl */
476 static void vrf_rt6_release(struct net_device *dev, struct net_vrf *vrf)
478 struct rt6_info *rt6 = rtnl_dereference(vrf->rt6);
479 struct net *net = dev_net(dev);
480 struct dst_entry *dst;
482 RCU_INIT_POINTER(vrf->rt6, NULL);
483 synchronize_rcu();
485 /* move dev in dst's to loopback so this VRF device can be deleted
486 * - based on dst_ifdown
488 if (rt6) {
489 dst = &rt6->dst;
490 dev_put(dst->dev);
491 dst->dev = net->loopback_dev;
492 dev_hold(dst->dev);
493 dst_release(dst);
497 static int vrf_rt6_create(struct net_device *dev)
499 int flags = DST_HOST | DST_NOPOLICY | DST_NOXFRM;
500 struct net_vrf *vrf = netdev_priv(dev);
501 struct net *net = dev_net(dev);
502 struct rt6_info *rt6;
503 int rc = -ENOMEM;
505 /* IPv6 can be CONFIG enabled and then disabled runtime */
506 if (!ipv6_mod_enabled())
507 return 0;
509 vrf->fib6_table = fib6_new_table(net, vrf->tb_id);
510 if (!vrf->fib6_table)
511 goto out;
513 /* create a dst for routing packets out a VRF device */
514 rt6 = ip6_dst_alloc(net, dev, flags);
515 if (!rt6)
516 goto out;
518 rt6->dst.output = vrf_output6;
520 rcu_assign_pointer(vrf->rt6, rt6);
522 rc = 0;
523 out:
524 return rc;
526 #else
527 static struct sk_buff *vrf_ip6_out(struct net_device *vrf_dev,
528 struct sock *sk,
529 struct sk_buff *skb)
531 return skb;
534 static void vrf_rt6_release(struct net_device *dev, struct net_vrf *vrf)
538 static int vrf_rt6_create(struct net_device *dev)
540 return 0;
542 #endif
544 /* modelled after ip_finish_output2 */
545 static int vrf_finish_output(struct net *net, struct sock *sk, struct sk_buff *skb)
547 struct dst_entry *dst = skb_dst(skb);
548 struct rtable *rt = (struct rtable *)dst;
549 struct net_device *dev = dst->dev;
550 unsigned int hh_len = LL_RESERVED_SPACE(dev);
551 struct neighbour *neigh;
552 u32 nexthop;
553 int ret = -EINVAL;
555 nf_reset(skb);
557 /* Be paranoid, rather than too clever. */
558 if (unlikely(skb_headroom(skb) < hh_len && dev->header_ops)) {
559 struct sk_buff *skb2;
561 skb2 = skb_realloc_headroom(skb, LL_RESERVED_SPACE(dev));
562 if (!skb2) {
563 ret = -ENOMEM;
564 goto err;
566 if (skb->sk)
567 skb_set_owner_w(skb2, skb->sk);
569 consume_skb(skb);
570 skb = skb2;
573 rcu_read_lock_bh();
575 nexthop = (__force u32)rt_nexthop(rt, ip_hdr(skb)->daddr);
576 neigh = __ipv4_neigh_lookup_noref(dev, nexthop);
577 if (unlikely(!neigh))
578 neigh = __neigh_create(&arp_tbl, &nexthop, dev, false);
579 if (!IS_ERR(neigh)) {
580 sock_confirm_neigh(skb, neigh);
581 ret = neigh_output(neigh, skb);
582 rcu_read_unlock_bh();
583 return ret;
586 rcu_read_unlock_bh();
587 err:
588 vrf_tx_error(skb->dev, skb);
589 return ret;
592 static int vrf_output(struct net *net, struct sock *sk, struct sk_buff *skb)
594 struct net_device *dev = skb_dst(skb)->dev;
596 IP_UPD_PO_STATS(net, IPSTATS_MIB_OUT, skb->len);
598 skb->dev = dev;
599 skb->protocol = htons(ETH_P_IP);
601 return NF_HOOK_COND(NFPROTO_IPV4, NF_INET_POST_ROUTING,
602 net, sk, skb, NULL, dev,
603 vrf_finish_output,
604 !(IPCB(skb)->flags & IPSKB_REROUTED));
607 /* set dst on skb to send packet to us via dev_xmit path. Allows
608 * packet to go through device based features such as qdisc, netfilter
609 * hooks and packet sockets with skb->dev set to vrf device.
611 static struct sk_buff *vrf_ip_out_redirect(struct net_device *vrf_dev,
612 struct sk_buff *skb)
614 struct net_vrf *vrf = netdev_priv(vrf_dev);
615 struct dst_entry *dst = NULL;
616 struct rtable *rth;
618 rcu_read_lock();
620 rth = rcu_dereference(vrf->rth);
621 if (likely(rth)) {
622 dst = &rth->dst;
623 dst_hold(dst);
626 rcu_read_unlock();
628 if (unlikely(!dst)) {
629 vrf_tx_error(vrf_dev, skb);
630 return NULL;
633 skb_dst_drop(skb);
634 skb_dst_set(skb, dst);
636 return skb;
639 static int vrf_output_direct(struct net *net, struct sock *sk,
640 struct sk_buff *skb)
642 skb->protocol = htons(ETH_P_IP);
644 return NF_HOOK_COND(NFPROTO_IPV4, NF_INET_POST_ROUTING,
645 net, sk, skb, NULL, skb->dev,
646 vrf_finish_direct,
647 !(IPCB(skb)->flags & IPSKB_REROUTED));
650 static struct sk_buff *vrf_ip_out_direct(struct net_device *vrf_dev,
651 struct sock *sk,
652 struct sk_buff *skb)
654 struct net *net = dev_net(vrf_dev);
655 int err;
657 skb->dev = vrf_dev;
659 err = nf_hook(NFPROTO_IPV4, NF_INET_LOCAL_OUT, net, sk,
660 skb, NULL, vrf_dev, vrf_output_direct);
662 if (likely(err == 1))
663 err = vrf_output_direct(net, sk, skb);
665 /* reset skb device */
666 if (likely(err == 1))
667 nf_reset(skb);
668 else
669 skb = NULL;
671 return skb;
674 static struct sk_buff *vrf_ip_out(struct net_device *vrf_dev,
675 struct sock *sk,
676 struct sk_buff *skb)
678 /* don't divert multicast or local broadcast */
679 if (ipv4_is_multicast(ip_hdr(skb)->daddr) ||
680 ipv4_is_lbcast(ip_hdr(skb)->daddr))
681 return skb;
683 if (qdisc_tx_is_default(vrf_dev))
684 return vrf_ip_out_direct(vrf_dev, sk, skb);
686 return vrf_ip_out_redirect(vrf_dev, skb);
689 /* called with rcu lock held */
690 static struct sk_buff *vrf_l3_out(struct net_device *vrf_dev,
691 struct sock *sk,
692 struct sk_buff *skb,
693 u16 proto)
695 switch (proto) {
696 case AF_INET:
697 return vrf_ip_out(vrf_dev, sk, skb);
698 case AF_INET6:
699 return vrf_ip6_out(vrf_dev, sk, skb);
702 return skb;
705 /* holding rtnl */
706 static void vrf_rtable_release(struct net_device *dev, struct net_vrf *vrf)
708 struct rtable *rth = rtnl_dereference(vrf->rth);
709 struct net *net = dev_net(dev);
710 struct dst_entry *dst;
712 RCU_INIT_POINTER(vrf->rth, NULL);
713 synchronize_rcu();
715 /* move dev in dst's to loopback so this VRF device can be deleted
716 * - based on dst_ifdown
718 if (rth) {
719 dst = &rth->dst;
720 dev_put(dst->dev);
721 dst->dev = net->loopback_dev;
722 dev_hold(dst->dev);
723 dst_release(dst);
727 static int vrf_rtable_create(struct net_device *dev)
729 struct net_vrf *vrf = netdev_priv(dev);
730 struct rtable *rth;
732 if (!fib_new_table(dev_net(dev), vrf->tb_id))
733 return -ENOMEM;
735 /* create a dst for routing packets out through a VRF device */
736 rth = rt_dst_alloc(dev, 0, RTN_UNICAST, 1, 1, 0);
737 if (!rth)
738 return -ENOMEM;
740 rth->dst.output = vrf_output;
742 rcu_assign_pointer(vrf->rth, rth);
744 return 0;
747 /**************************** device handling ********************/
749 /* cycle interface to flush neighbor cache and move routes across tables */
750 static void cycle_netdev(struct net_device *dev)
752 unsigned int flags = dev->flags;
753 int ret;
755 if (!netif_running(dev))
756 return;
758 ret = dev_change_flags(dev, flags & ~IFF_UP);
759 if (ret >= 0)
760 ret = dev_change_flags(dev, flags);
762 if (ret < 0) {
763 netdev_err(dev,
764 "Failed to cycle device %s; route tables might be wrong!\n",
765 dev->name);
769 static int do_vrf_add_slave(struct net_device *dev, struct net_device *port_dev,
770 struct netlink_ext_ack *extack)
772 int ret;
774 /* do not allow loopback device to be enslaved to a VRF.
775 * The vrf device acts as the loopback for the vrf.
777 if (port_dev == dev_net(dev)->loopback_dev) {
778 NL_SET_ERR_MSG(extack,
779 "Can not enslave loopback device to a VRF");
780 return -EOPNOTSUPP;
783 port_dev->priv_flags |= IFF_L3MDEV_SLAVE;
784 ret = netdev_master_upper_dev_link(port_dev, dev, NULL, NULL, extack);
785 if (ret < 0)
786 goto err;
788 cycle_netdev(port_dev);
790 return 0;
792 err:
793 port_dev->priv_flags &= ~IFF_L3MDEV_SLAVE;
794 return ret;
797 static int vrf_add_slave(struct net_device *dev, struct net_device *port_dev,
798 struct netlink_ext_ack *extack)
800 if (netif_is_l3_master(port_dev)) {
801 NL_SET_ERR_MSG(extack,
802 "Can not enslave an L3 master device to a VRF");
803 return -EINVAL;
806 if (netif_is_l3_slave(port_dev))
807 return -EINVAL;
809 return do_vrf_add_slave(dev, port_dev, extack);
812 /* inverse of do_vrf_add_slave */
813 static int do_vrf_del_slave(struct net_device *dev, struct net_device *port_dev)
815 netdev_upper_dev_unlink(port_dev, dev);
816 port_dev->priv_flags &= ~IFF_L3MDEV_SLAVE;
818 cycle_netdev(port_dev);
820 return 0;
823 static int vrf_del_slave(struct net_device *dev, struct net_device *port_dev)
825 return do_vrf_del_slave(dev, port_dev);
828 static void vrf_dev_uninit(struct net_device *dev)
830 struct net_vrf *vrf = netdev_priv(dev);
832 vrf_rtable_release(dev, vrf);
833 vrf_rt6_release(dev, vrf);
835 free_percpu(dev->dstats);
836 dev->dstats = NULL;
839 static int vrf_dev_init(struct net_device *dev)
841 struct net_vrf *vrf = netdev_priv(dev);
843 dev->dstats = netdev_alloc_pcpu_stats(struct pcpu_dstats);
844 if (!dev->dstats)
845 goto out_nomem;
847 /* create the default dst which points back to us */
848 if (vrf_rtable_create(dev) != 0)
849 goto out_stats;
851 if (vrf_rt6_create(dev) != 0)
852 goto out_rth;
854 dev->flags = IFF_MASTER | IFF_NOARP;
856 /* MTU is irrelevant for VRF device; set to 64k similar to lo */
857 dev->mtu = 64 * 1024;
859 /* similarly, oper state is irrelevant; set to up to avoid confusion */
860 dev->operstate = IF_OPER_UP;
861 netdev_lockdep_set_classes(dev);
862 return 0;
864 out_rth:
865 vrf_rtable_release(dev, vrf);
866 out_stats:
867 free_percpu(dev->dstats);
868 dev->dstats = NULL;
869 out_nomem:
870 return -ENOMEM;
873 static const struct net_device_ops vrf_netdev_ops = {
874 .ndo_init = vrf_dev_init,
875 .ndo_uninit = vrf_dev_uninit,
876 .ndo_start_xmit = vrf_xmit,
877 .ndo_get_stats64 = vrf_get_stats64,
878 .ndo_add_slave = vrf_add_slave,
879 .ndo_del_slave = vrf_del_slave,
882 static u32 vrf_fib_table(const struct net_device *dev)
884 struct net_vrf *vrf = netdev_priv(dev);
886 return vrf->tb_id;
889 static int vrf_rcv_finish(struct net *net, struct sock *sk, struct sk_buff *skb)
891 kfree_skb(skb);
892 return 0;
895 static struct sk_buff *vrf_rcv_nfhook(u8 pf, unsigned int hook,
896 struct sk_buff *skb,
897 struct net_device *dev)
899 struct net *net = dev_net(dev);
901 if (nf_hook(pf, hook, net, NULL, skb, dev, NULL, vrf_rcv_finish) != 1)
902 skb = NULL; /* kfree_skb(skb) handled by nf code */
904 return skb;
907 #if IS_ENABLED(CONFIG_IPV6)
908 /* neighbor handling is done with actual device; do not want
909 * to flip skb->dev for those ndisc packets. This really fails
910 * for multiple next protocols (e.g., NEXTHDR_HOP). But it is
911 * a start.
913 static bool ipv6_ndisc_frame(const struct sk_buff *skb)
915 const struct ipv6hdr *iph = ipv6_hdr(skb);
916 bool rc = false;
918 if (iph->nexthdr == NEXTHDR_ICMP) {
919 const struct icmp6hdr *icmph;
920 struct icmp6hdr _icmph;
922 icmph = skb_header_pointer(skb, sizeof(*iph),
923 sizeof(_icmph), &_icmph);
924 if (!icmph)
925 goto out;
927 switch (icmph->icmp6_type) {
928 case NDISC_ROUTER_SOLICITATION:
929 case NDISC_ROUTER_ADVERTISEMENT:
930 case NDISC_NEIGHBOUR_SOLICITATION:
931 case NDISC_NEIGHBOUR_ADVERTISEMENT:
932 case NDISC_REDIRECT:
933 rc = true;
934 break;
938 out:
939 return rc;
942 static struct rt6_info *vrf_ip6_route_lookup(struct net *net,
943 const struct net_device *dev,
944 struct flowi6 *fl6,
945 int ifindex,
946 const struct sk_buff *skb,
947 int flags)
949 struct net_vrf *vrf = netdev_priv(dev);
951 return ip6_pol_route(net, vrf->fib6_table, ifindex, fl6, skb, flags);
954 static void vrf_ip6_input_dst(struct sk_buff *skb, struct net_device *vrf_dev,
955 int ifindex)
957 const struct ipv6hdr *iph = ipv6_hdr(skb);
958 struct flowi6 fl6 = {
959 .flowi6_iif = ifindex,
960 .flowi6_mark = skb->mark,
961 .flowi6_proto = iph->nexthdr,
962 .daddr = iph->daddr,
963 .saddr = iph->saddr,
964 .flowlabel = ip6_flowinfo(iph),
966 struct net *net = dev_net(vrf_dev);
967 struct rt6_info *rt6;
969 rt6 = vrf_ip6_route_lookup(net, vrf_dev, &fl6, ifindex, skb,
970 RT6_LOOKUP_F_HAS_SADDR | RT6_LOOKUP_F_IFACE);
971 if (unlikely(!rt6))
972 return;
974 if (unlikely(&rt6->dst == &net->ipv6.ip6_null_entry->dst))
975 return;
977 skb_dst_set(skb, &rt6->dst);
980 static struct sk_buff *vrf_ip6_rcv(struct net_device *vrf_dev,
981 struct sk_buff *skb)
983 int orig_iif = skb->skb_iif;
984 bool need_strict;
986 /* loopback traffic; do not push through packet taps again.
987 * Reset pkt_type for upper layers to process skb
989 if (skb->pkt_type == PACKET_LOOPBACK) {
990 skb->dev = vrf_dev;
991 skb->skb_iif = vrf_dev->ifindex;
992 IP6CB(skb)->flags |= IP6SKB_L3SLAVE;
993 skb->pkt_type = PACKET_HOST;
994 goto out;
997 /* if packet is NDISC or addressed to multicast or link-local
998 * then keep the ingress interface
1000 need_strict = rt6_need_strict(&ipv6_hdr(skb)->daddr);
1001 if (!ipv6_ndisc_frame(skb) && !need_strict) {
1002 vrf_rx_stats(vrf_dev, skb->len);
1003 skb->dev = vrf_dev;
1004 skb->skb_iif = vrf_dev->ifindex;
1006 if (!list_empty(&vrf_dev->ptype_all)) {
1007 skb_push(skb, skb->mac_len);
1008 dev_queue_xmit_nit(skb, vrf_dev);
1009 skb_pull(skb, skb->mac_len);
1012 IP6CB(skb)->flags |= IP6SKB_L3SLAVE;
1015 if (need_strict)
1016 vrf_ip6_input_dst(skb, vrf_dev, orig_iif);
1018 skb = vrf_rcv_nfhook(NFPROTO_IPV6, NF_INET_PRE_ROUTING, skb, vrf_dev);
1019 out:
1020 return skb;
1023 #else
1024 static struct sk_buff *vrf_ip6_rcv(struct net_device *vrf_dev,
1025 struct sk_buff *skb)
1027 return skb;
1029 #endif
1031 static struct sk_buff *vrf_ip_rcv(struct net_device *vrf_dev,
1032 struct sk_buff *skb)
1034 skb->dev = vrf_dev;
1035 skb->skb_iif = vrf_dev->ifindex;
1036 IPCB(skb)->flags |= IPSKB_L3SLAVE;
1038 if (ipv4_is_multicast(ip_hdr(skb)->daddr))
1039 goto out;
1041 /* loopback traffic; do not push through packet taps again.
1042 * Reset pkt_type for upper layers to process skb
1044 if (skb->pkt_type == PACKET_LOOPBACK) {
1045 skb->pkt_type = PACKET_HOST;
1046 goto out;
1049 vrf_rx_stats(vrf_dev, skb->len);
1051 if (!list_empty(&vrf_dev->ptype_all)) {
1052 skb_push(skb, skb->mac_len);
1053 dev_queue_xmit_nit(skb, vrf_dev);
1054 skb_pull(skb, skb->mac_len);
1057 skb = vrf_rcv_nfhook(NFPROTO_IPV4, NF_INET_PRE_ROUTING, skb, vrf_dev);
1058 out:
1059 return skb;
1062 /* called with rcu lock held */
1063 static struct sk_buff *vrf_l3_rcv(struct net_device *vrf_dev,
1064 struct sk_buff *skb,
1065 u16 proto)
1067 switch (proto) {
1068 case AF_INET:
1069 return vrf_ip_rcv(vrf_dev, skb);
1070 case AF_INET6:
1071 return vrf_ip6_rcv(vrf_dev, skb);
1074 return skb;
1077 #if IS_ENABLED(CONFIG_IPV6)
1078 /* send to link-local or multicast address via interface enslaved to
1079 * VRF device. Force lookup to VRF table without changing flow struct
1081 static struct dst_entry *vrf_link_scope_lookup(const struct net_device *dev,
1082 struct flowi6 *fl6)
1084 struct net *net = dev_net(dev);
1085 int flags = RT6_LOOKUP_F_IFACE;
1086 struct dst_entry *dst = NULL;
1087 struct rt6_info *rt;
1089 /* VRF device does not have a link-local address and
1090 * sending packets to link-local or mcast addresses over
1091 * a VRF device does not make sense
1093 if (fl6->flowi6_oif == dev->ifindex) {
1094 dst = &net->ipv6.ip6_null_entry->dst;
1095 dst_hold(dst);
1096 return dst;
1099 if (!ipv6_addr_any(&fl6->saddr))
1100 flags |= RT6_LOOKUP_F_HAS_SADDR;
1102 rt = vrf_ip6_route_lookup(net, dev, fl6, fl6->flowi6_oif, NULL, flags);
1103 if (rt)
1104 dst = &rt->dst;
1106 return dst;
1108 #endif
1110 static const struct l3mdev_ops vrf_l3mdev_ops = {
1111 .l3mdev_fib_table = vrf_fib_table,
1112 .l3mdev_l3_rcv = vrf_l3_rcv,
1113 .l3mdev_l3_out = vrf_l3_out,
1114 #if IS_ENABLED(CONFIG_IPV6)
1115 .l3mdev_link_scope_lookup = vrf_link_scope_lookup,
1116 #endif
1119 static void vrf_get_drvinfo(struct net_device *dev,
1120 struct ethtool_drvinfo *info)
1122 strlcpy(info->driver, DRV_NAME, sizeof(info->driver));
1123 strlcpy(info->version, DRV_VERSION, sizeof(info->version));
1126 static const struct ethtool_ops vrf_ethtool_ops = {
1127 .get_drvinfo = vrf_get_drvinfo,
1130 static inline size_t vrf_fib_rule_nl_size(void)
1132 size_t sz;
1134 sz = NLMSG_ALIGN(sizeof(struct fib_rule_hdr));
1135 sz += nla_total_size(sizeof(u8)); /* FRA_L3MDEV */
1136 sz += nla_total_size(sizeof(u32)); /* FRA_PRIORITY */
1137 sz += nla_total_size(sizeof(u8)); /* FRA_PROTOCOL */
1139 return sz;
1142 static int vrf_fib_rule(const struct net_device *dev, __u8 family, bool add_it)
1144 struct fib_rule_hdr *frh;
1145 struct nlmsghdr *nlh;
1146 struct sk_buff *skb;
1147 int err;
1149 if (family == AF_INET6 && !ipv6_mod_enabled())
1150 return 0;
1152 skb = nlmsg_new(vrf_fib_rule_nl_size(), GFP_KERNEL);
1153 if (!skb)
1154 return -ENOMEM;
1156 nlh = nlmsg_put(skb, 0, 0, 0, sizeof(*frh), 0);
1157 if (!nlh)
1158 goto nla_put_failure;
1160 /* rule only needs to appear once */
1161 nlh->nlmsg_flags |= NLM_F_EXCL;
1163 frh = nlmsg_data(nlh);
1164 memset(frh, 0, sizeof(*frh));
1165 frh->family = family;
1166 frh->action = FR_ACT_TO_TBL;
1168 if (nla_put_u8(skb, FRA_PROTOCOL, RTPROT_KERNEL))
1169 goto nla_put_failure;
1171 if (nla_put_u8(skb, FRA_L3MDEV, 1))
1172 goto nla_put_failure;
1174 if (nla_put_u32(skb, FRA_PRIORITY, FIB_RULE_PREF))
1175 goto nla_put_failure;
1177 nlmsg_end(skb, nlh);
1179 /* fib_nl_{new,del}rule handling looks for net from skb->sk */
1180 skb->sk = dev_net(dev)->rtnl;
1181 if (add_it) {
1182 err = fib_nl_newrule(skb, nlh, NULL);
1183 if (err == -EEXIST)
1184 err = 0;
1185 } else {
1186 err = fib_nl_delrule(skb, nlh, NULL);
1187 if (err == -ENOENT)
1188 err = 0;
1190 nlmsg_free(skb);
1192 return err;
1194 nla_put_failure:
1195 nlmsg_free(skb);
1197 return -EMSGSIZE;
1200 static int vrf_add_fib_rules(const struct net_device *dev)
1202 int err;
1204 err = vrf_fib_rule(dev, AF_INET, true);
1205 if (err < 0)
1206 goto out_err;
1208 err = vrf_fib_rule(dev, AF_INET6, true);
1209 if (err < 0)
1210 goto ipv6_err;
1212 #if IS_ENABLED(CONFIG_IP_MROUTE_MULTIPLE_TABLES)
1213 err = vrf_fib_rule(dev, RTNL_FAMILY_IPMR, true);
1214 if (err < 0)
1215 goto ipmr_err;
1216 #endif
1218 return 0;
1220 #if IS_ENABLED(CONFIG_IP_MROUTE_MULTIPLE_TABLES)
1221 ipmr_err:
1222 vrf_fib_rule(dev, AF_INET6, false);
1223 #endif
1225 ipv6_err:
1226 vrf_fib_rule(dev, AF_INET, false);
1228 out_err:
1229 netdev_err(dev, "Failed to add FIB rules.\n");
1230 return err;
1233 static void vrf_setup(struct net_device *dev)
1235 ether_setup(dev);
1237 /* Initialize the device structure. */
1238 dev->netdev_ops = &vrf_netdev_ops;
1239 dev->l3mdev_ops = &vrf_l3mdev_ops;
1240 dev->ethtool_ops = &vrf_ethtool_ops;
1241 dev->needs_free_netdev = true;
1243 /* Fill in device structure with ethernet-generic values. */
1244 eth_hw_addr_random(dev);
1246 /* don't acquire vrf device's netif_tx_lock when transmitting */
1247 dev->features |= NETIF_F_LLTX;
1249 /* don't allow vrf devices to change network namespaces. */
1250 dev->features |= NETIF_F_NETNS_LOCAL;
1252 /* does not make sense for a VLAN to be added to a vrf device */
1253 dev->features |= NETIF_F_VLAN_CHALLENGED;
1255 /* enable offload features */
1256 dev->features |= NETIF_F_GSO_SOFTWARE;
1257 dev->features |= NETIF_F_RXCSUM | NETIF_F_HW_CSUM | NETIF_F_SCTP_CRC;
1258 dev->features |= NETIF_F_SG | NETIF_F_FRAGLIST | NETIF_F_HIGHDMA;
1260 dev->hw_features = dev->features;
1261 dev->hw_enc_features = dev->features;
1263 /* default to no qdisc; user can add if desired */
1264 dev->priv_flags |= IFF_NO_QUEUE;
1267 static int vrf_validate(struct nlattr *tb[], struct nlattr *data[],
1268 struct netlink_ext_ack *extack)
1270 if (tb[IFLA_ADDRESS]) {
1271 if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN) {
1272 NL_SET_ERR_MSG(extack, "Invalid hardware address");
1273 return -EINVAL;
1275 if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS]))) {
1276 NL_SET_ERR_MSG(extack, "Invalid hardware address");
1277 return -EADDRNOTAVAIL;
1280 return 0;
1283 static void vrf_dellink(struct net_device *dev, struct list_head *head)
1285 struct net_device *port_dev;
1286 struct list_head *iter;
1288 netdev_for_each_lower_dev(dev, port_dev, iter)
1289 vrf_del_slave(dev, port_dev);
1291 unregister_netdevice_queue(dev, head);
1294 static int vrf_newlink(struct net *src_net, struct net_device *dev,
1295 struct nlattr *tb[], struct nlattr *data[],
1296 struct netlink_ext_ack *extack)
1298 struct net_vrf *vrf = netdev_priv(dev);
1299 bool *add_fib_rules;
1300 struct net *net;
1301 int err;
1303 if (!data || !data[IFLA_VRF_TABLE]) {
1304 NL_SET_ERR_MSG(extack, "VRF table id is missing");
1305 return -EINVAL;
1308 vrf->tb_id = nla_get_u32(data[IFLA_VRF_TABLE]);
1309 if (vrf->tb_id == RT_TABLE_UNSPEC) {
1310 NL_SET_ERR_MSG_ATTR(extack, data[IFLA_VRF_TABLE],
1311 "Invalid VRF table id");
1312 return -EINVAL;
1315 dev->priv_flags |= IFF_L3MDEV_MASTER;
1317 err = register_netdevice(dev);
1318 if (err)
1319 goto out;
1321 net = dev_net(dev);
1322 add_fib_rules = net_generic(net, vrf_net_id);
1323 if (*add_fib_rules) {
1324 err = vrf_add_fib_rules(dev);
1325 if (err) {
1326 unregister_netdevice(dev);
1327 goto out;
1329 *add_fib_rules = false;
1332 out:
1333 return err;
1336 static size_t vrf_nl_getsize(const struct net_device *dev)
1338 return nla_total_size(sizeof(u32)); /* IFLA_VRF_TABLE */
1341 static int vrf_fillinfo(struct sk_buff *skb,
1342 const struct net_device *dev)
1344 struct net_vrf *vrf = netdev_priv(dev);
1346 return nla_put_u32(skb, IFLA_VRF_TABLE, vrf->tb_id);
1349 static size_t vrf_get_slave_size(const struct net_device *bond_dev,
1350 const struct net_device *slave_dev)
1352 return nla_total_size(sizeof(u32)); /* IFLA_VRF_PORT_TABLE */
1355 static int vrf_fill_slave_info(struct sk_buff *skb,
1356 const struct net_device *vrf_dev,
1357 const struct net_device *slave_dev)
1359 struct net_vrf *vrf = netdev_priv(vrf_dev);
1361 if (nla_put_u32(skb, IFLA_VRF_PORT_TABLE, vrf->tb_id))
1362 return -EMSGSIZE;
1364 return 0;
1367 static const struct nla_policy vrf_nl_policy[IFLA_VRF_MAX + 1] = {
1368 [IFLA_VRF_TABLE] = { .type = NLA_U32 },
1371 static struct rtnl_link_ops vrf_link_ops __read_mostly = {
1372 .kind = DRV_NAME,
1373 .priv_size = sizeof(struct net_vrf),
1375 .get_size = vrf_nl_getsize,
1376 .policy = vrf_nl_policy,
1377 .validate = vrf_validate,
1378 .fill_info = vrf_fillinfo,
1380 .get_slave_size = vrf_get_slave_size,
1381 .fill_slave_info = vrf_fill_slave_info,
1383 .newlink = vrf_newlink,
1384 .dellink = vrf_dellink,
1385 .setup = vrf_setup,
1386 .maxtype = IFLA_VRF_MAX,
1389 static int vrf_device_event(struct notifier_block *unused,
1390 unsigned long event, void *ptr)
1392 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
1394 /* only care about unregister events to drop slave references */
1395 if (event == NETDEV_UNREGISTER) {
1396 struct net_device *vrf_dev;
1398 if (!netif_is_l3_slave(dev))
1399 goto out;
1401 vrf_dev = netdev_master_upper_dev_get(dev);
1402 vrf_del_slave(vrf_dev, dev);
1404 out:
1405 return NOTIFY_DONE;
1408 static struct notifier_block vrf_notifier_block __read_mostly = {
1409 .notifier_call = vrf_device_event,
1412 /* Initialize per network namespace state */
1413 static int __net_init vrf_netns_init(struct net *net)
1415 bool *add_fib_rules = net_generic(net, vrf_net_id);
1417 *add_fib_rules = true;
1419 return 0;
1422 static struct pernet_operations vrf_net_ops __net_initdata = {
1423 .init = vrf_netns_init,
1424 .id = &vrf_net_id,
1425 .size = sizeof(bool),
1428 static int __init vrf_init_module(void)
1430 int rc;
1432 register_netdevice_notifier(&vrf_notifier_block);
1434 rc = register_pernet_subsys(&vrf_net_ops);
1435 if (rc < 0)
1436 goto error;
1438 rc = rtnl_link_register(&vrf_link_ops);
1439 if (rc < 0) {
1440 unregister_pernet_subsys(&vrf_net_ops);
1441 goto error;
1444 return 0;
1446 error:
1447 unregister_netdevice_notifier(&vrf_notifier_block);
1448 return rc;
1451 module_init(vrf_init_module);
1452 MODULE_AUTHOR("Shrijeet Mukherjee, David Ahern");
1453 MODULE_DESCRIPTION("Device driver to instantiate VRF domains");
1454 MODULE_LICENSE("GPL");
1455 MODULE_ALIAS_RTNL_LINK(DRV_NAME);
1456 MODULE_VERSION(DRV_VERSION);