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>
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>
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>
40 #define DRV_NAME "vrf"
41 #define DRV_VERSION "1.0"
43 #define FIB_RULE_PREF 1000 /* default preference for FIB rules */
44 static bool add_fib_rules = true;
47 struct rtable __rcu *rth;
48 struct rtable __rcu *rth_local;
49 struct rt6_info __rcu *rt6;
50 struct rt6_info __rcu *rt6_local;
61 struct u64_stats_sync syncp;
64 static void vrf_rx_stats(struct net_device *dev, int len)
66 struct pcpu_dstats *dstats = this_cpu_ptr(dev->dstats);
68 u64_stats_update_begin(&dstats->syncp);
70 dstats->rx_bytes += len;
71 u64_stats_update_end(&dstats->syncp);
74 static void vrf_tx_error(struct net_device *vrf_dev, struct sk_buff *skb)
76 vrf_dev->stats.tx_errors++;
80 static void vrf_get_stats64(struct net_device *dev,
81 struct rtnl_link_stats64 *stats)
85 for_each_possible_cpu(i) {
86 const struct pcpu_dstats *dstats;
87 u64 tbytes, tpkts, tdrops, rbytes, rpkts;
90 dstats = per_cpu_ptr(dev->dstats, i);
92 start = u64_stats_fetch_begin_irq(&dstats->syncp);
93 tbytes = dstats->tx_bytes;
94 tpkts = dstats->tx_pkts;
95 tdrops = dstats->tx_drps;
96 rbytes = dstats->rx_bytes;
97 rpkts = dstats->rx_pkts;
98 } while (u64_stats_fetch_retry_irq(&dstats->syncp, start));
99 stats->tx_bytes += tbytes;
100 stats->tx_packets += tpkts;
101 stats->tx_dropped += tdrops;
102 stats->rx_bytes += rbytes;
103 stats->rx_packets += rpkts;
107 /* Local traffic destined to local address. Reinsert the packet to rx
108 * path, similar to loopback handling.
110 static int vrf_local_xmit(struct sk_buff *skb, struct net_device *dev,
111 struct dst_entry *dst)
117 skb_dst_set(skb, dst);
120 /* set pkt_type to avoid skb hitting packet taps twice -
121 * once on Tx and again in Rx processing
123 skb->pkt_type = PACKET_LOOPBACK;
125 skb->protocol = eth_type_trans(skb, dev);
127 if (likely(netif_rx(skb) == NET_RX_SUCCESS))
128 vrf_rx_stats(dev, len);
130 this_cpu_inc(dev->dstats->rx_drps);
135 #if IS_ENABLED(CONFIG_IPV6)
136 static int vrf_ip6_local_out(struct net *net, struct sock *sk,
141 err = nf_hook(NFPROTO_IPV6, NF_INET_LOCAL_OUT, net,
142 sk, skb, NULL, skb_dst(skb)->dev, dst_output);
144 if (likely(err == 1))
145 err = dst_output(net, sk, skb);
150 static netdev_tx_t vrf_process_v6_outbound(struct sk_buff *skb,
151 struct net_device *dev)
153 const struct ipv6hdr *iph = ipv6_hdr(skb);
154 struct net *net = dev_net(skb->dev);
155 struct flowi6 fl6 = {
156 /* needed to match OIF rule */
157 .flowi6_oif = dev->ifindex,
158 .flowi6_iif = LOOPBACK_IFINDEX,
161 .flowlabel = ip6_flowinfo(iph),
162 .flowi6_mark = skb->mark,
163 .flowi6_proto = iph->nexthdr,
164 .flowi6_flags = FLOWI_FLAG_SKIP_NH_OIF,
166 int ret = NET_XMIT_DROP;
167 struct dst_entry *dst;
168 struct dst_entry *dst_null = &net->ipv6.ip6_null_entry->dst;
170 dst = ip6_route_output(net, NULL, &fl6);
176 /* if dst.dev is loopback or the VRF device again this is locally
177 * originated traffic destined to a local address. Short circuit
178 * to Rx path using our local dst
180 if (dst->dev == net->loopback_dev || dst->dev == dev) {
181 struct net_vrf *vrf = netdev_priv(dev);
182 struct rt6_info *rt6_local;
184 /* release looked up dst and use cached local dst */
189 rt6_local = rcu_dereference(vrf->rt6_local);
190 if (unlikely(!rt6_local)) {
195 /* Ordering issue: cached local dst is created on newlink
196 * before the IPv6 initialization. Using the local dst
197 * requires rt6i_idev to be set so make sure it is.
199 if (unlikely(!rt6_local->rt6i_idev)) {
200 rt6_local->rt6i_idev = in6_dev_get(dev);
201 if (!rt6_local->rt6i_idev) {
207 dst = &rt6_local->dst;
212 return vrf_local_xmit(skb, dev, &rt6_local->dst);
215 skb_dst_set(skb, dst);
217 /* strip the ethernet header added for pass through VRF device */
218 __skb_pull(skb, skb_network_offset(skb));
220 ret = vrf_ip6_local_out(net, skb->sk, skb);
221 if (unlikely(net_xmit_eval(ret)))
222 dev->stats.tx_errors++;
224 ret = NET_XMIT_SUCCESS;
228 vrf_tx_error(dev, skb);
229 return NET_XMIT_DROP;
232 static netdev_tx_t vrf_process_v6_outbound(struct sk_buff *skb,
233 struct net_device *dev)
235 vrf_tx_error(dev, skb);
236 return NET_XMIT_DROP;
240 /* based on ip_local_out; can't use it b/c the dst is switched pointing to us */
241 static int vrf_ip_local_out(struct net *net, struct sock *sk,
246 err = nf_hook(NFPROTO_IPV4, NF_INET_LOCAL_OUT, net, sk,
247 skb, NULL, skb_dst(skb)->dev, dst_output);
248 if (likely(err == 1))
249 err = dst_output(net, sk, skb);
254 static netdev_tx_t vrf_process_v4_outbound(struct sk_buff *skb,
255 struct net_device *vrf_dev)
257 struct iphdr *ip4h = ip_hdr(skb);
258 int ret = NET_XMIT_DROP;
259 struct flowi4 fl4 = {
260 /* needed to match OIF rule */
261 .flowi4_oif = vrf_dev->ifindex,
262 .flowi4_iif = LOOPBACK_IFINDEX,
263 .flowi4_tos = RT_TOS(ip4h->tos),
264 .flowi4_flags = FLOWI_FLAG_ANYSRC | FLOWI_FLAG_SKIP_NH_OIF,
265 .flowi4_proto = ip4h->protocol,
266 .daddr = ip4h->daddr,
267 .saddr = ip4h->saddr,
269 struct net *net = dev_net(vrf_dev);
272 rt = ip_route_output_flow(net, &fl4, NULL);
278 /* if dst.dev is loopback or the VRF device again this is locally
279 * originated traffic destined to a local address. Short circuit
280 * to Rx path using our local dst
282 if (rt->dst.dev == net->loopback_dev || rt->dst.dev == vrf_dev) {
283 struct net_vrf *vrf = netdev_priv(vrf_dev);
284 struct rtable *rth_local;
285 struct dst_entry *dst = NULL;
291 rth_local = rcu_dereference(vrf->rth_local);
292 if (likely(rth_local)) {
293 dst = &rth_local->dst;
302 return vrf_local_xmit(skb, vrf_dev, dst);
305 skb_dst_set(skb, &rt->dst);
307 /* strip the ethernet header added for pass through VRF device */
308 __skb_pull(skb, skb_network_offset(skb));
311 ip4h->saddr = inet_select_addr(skb_dst(skb)->dev, 0,
315 ret = vrf_ip_local_out(dev_net(skb_dst(skb)->dev), skb->sk, skb);
316 if (unlikely(net_xmit_eval(ret)))
317 vrf_dev->stats.tx_errors++;
319 ret = NET_XMIT_SUCCESS;
324 vrf_tx_error(vrf_dev, skb);
328 static netdev_tx_t is_ip_tx_frame(struct sk_buff *skb, struct net_device *dev)
330 switch (skb->protocol) {
331 case htons(ETH_P_IP):
332 return vrf_process_v4_outbound(skb, dev);
333 case htons(ETH_P_IPV6):
334 return vrf_process_v6_outbound(skb, dev);
336 vrf_tx_error(dev, skb);
337 return NET_XMIT_DROP;
341 static netdev_tx_t vrf_xmit(struct sk_buff *skb, struct net_device *dev)
343 netdev_tx_t ret = is_ip_tx_frame(skb, dev);
345 if (likely(ret == NET_XMIT_SUCCESS || ret == NET_XMIT_CN)) {
346 struct pcpu_dstats *dstats = this_cpu_ptr(dev->dstats);
348 u64_stats_update_begin(&dstats->syncp);
350 dstats->tx_bytes += skb->len;
351 u64_stats_update_end(&dstats->syncp);
353 this_cpu_inc(dev->dstats->tx_drps);
359 #if IS_ENABLED(CONFIG_IPV6)
360 /* modelled after ip6_finish_output2 */
361 static int vrf_finish_output6(struct net *net, struct sock *sk,
364 struct dst_entry *dst = skb_dst(skb);
365 struct net_device *dev = dst->dev;
366 struct neighbour *neigh;
367 struct in6_addr *nexthop;
372 skb->protocol = htons(ETH_P_IPV6);
376 nexthop = rt6_nexthop((struct rt6_info *)dst, &ipv6_hdr(skb)->daddr);
377 neigh = __ipv6_neigh_lookup_noref(dst->dev, nexthop);
378 if (unlikely(!neigh))
379 neigh = __neigh_create(&nd_tbl, nexthop, dst->dev, false);
380 if (!IS_ERR(neigh)) {
381 sock_confirm_neigh(skb, neigh);
382 ret = neigh_output(neigh, skb);
383 rcu_read_unlock_bh();
386 rcu_read_unlock_bh();
388 IP6_INC_STATS(dev_net(dst->dev),
389 ip6_dst_idev(dst), IPSTATS_MIB_OUTNOROUTES);
394 /* modelled after ip6_output */
395 static int vrf_output6(struct net *net, struct sock *sk, struct sk_buff *skb)
397 return NF_HOOK_COND(NFPROTO_IPV6, NF_INET_POST_ROUTING,
398 net, sk, skb, NULL, skb_dst(skb)->dev,
400 !(IP6CB(skb)->flags & IP6SKB_REROUTED));
403 /* set dst on skb to send packet to us via dev_xmit path. Allows
404 * packet to go through device based features such as qdisc, netfilter
405 * hooks and packet sockets with skb->dev set to vrf device.
407 static struct sk_buff *vrf_ip6_out(struct net_device *vrf_dev,
411 struct net_vrf *vrf = netdev_priv(vrf_dev);
412 struct dst_entry *dst = NULL;
413 struct rt6_info *rt6;
415 /* don't divert link scope packets */
416 if (rt6_need_strict(&ipv6_hdr(skb)->daddr))
421 rt6 = rcu_dereference(vrf->rt6);
429 if (unlikely(!dst)) {
430 vrf_tx_error(vrf_dev, skb);
435 skb_dst_set(skb, dst);
441 static void vrf_rt6_release(struct net_device *dev, struct net_vrf *vrf)
443 struct rt6_info *rt6 = rtnl_dereference(vrf->rt6);
444 struct rt6_info *rt6_local = rtnl_dereference(vrf->rt6_local);
445 struct net *net = dev_net(dev);
446 struct dst_entry *dst;
448 RCU_INIT_POINTER(vrf->rt6, NULL);
449 RCU_INIT_POINTER(vrf->rt6_local, NULL);
452 /* move dev in dst's to loopback so this VRF device can be deleted
453 * - based on dst_ifdown
458 dst->dev = net->loopback_dev;
464 if (rt6_local->rt6i_idev)
465 in6_dev_put(rt6_local->rt6i_idev);
467 dst = &rt6_local->dst;
469 dst->dev = net->loopback_dev;
475 static int vrf_rt6_create(struct net_device *dev)
477 int flags = DST_HOST | DST_NOPOLICY | DST_NOXFRM | DST_NOCACHE;
478 struct net_vrf *vrf = netdev_priv(dev);
479 struct net *net = dev_net(dev);
480 struct fib6_table *rt6i_table;
481 struct rt6_info *rt6, *rt6_local;
484 /* IPv6 can be CONFIG enabled and then disabled runtime */
485 if (!ipv6_mod_enabled())
488 rt6i_table = fib6_new_table(net, vrf->tb_id);
492 /* create a dst for routing packets out a VRF device */
493 rt6 = ip6_dst_alloc(net, dev, flags);
499 rt6->rt6i_table = rt6i_table;
500 rt6->dst.output = vrf_output6;
502 /* create a dst for local routing - packets sent locally
503 * to local address via the VRF device as a loopback
505 rt6_local = ip6_dst_alloc(net, dev, flags);
507 dst_release(&rt6->dst);
511 dst_hold(&rt6_local->dst);
513 rt6_local->rt6i_idev = in6_dev_get(dev);
514 rt6_local->rt6i_flags = RTF_UP | RTF_NONEXTHOP | RTF_LOCAL;
515 rt6_local->rt6i_table = rt6i_table;
516 rt6_local->dst.input = ip6_input;
518 rcu_assign_pointer(vrf->rt6, rt6);
519 rcu_assign_pointer(vrf->rt6_local, rt6_local);
526 static struct sk_buff *vrf_ip6_out(struct net_device *vrf_dev,
533 static void vrf_rt6_release(struct net_device *dev, struct net_vrf *vrf)
537 static int vrf_rt6_create(struct net_device *dev)
543 /* modelled after ip_finish_output2 */
544 static int vrf_finish_output(struct net *net, struct sock *sk, struct sk_buff *skb)
546 struct dst_entry *dst = skb_dst(skb);
547 struct rtable *rt = (struct rtable *)dst;
548 struct net_device *dev = dst->dev;
549 unsigned int hh_len = LL_RESERVED_SPACE(dev);
550 struct neighbour *neigh;
556 /* Be paranoid, rather than too clever. */
557 if (unlikely(skb_headroom(skb) < hh_len && dev->header_ops)) {
558 struct sk_buff *skb2;
560 skb2 = skb_realloc_headroom(skb, LL_RESERVED_SPACE(dev));
566 skb_set_owner_w(skb2, skb->sk);
574 nexthop = (__force u32)rt_nexthop(rt, ip_hdr(skb)->daddr);
575 neigh = __ipv4_neigh_lookup_noref(dev, nexthop);
576 if (unlikely(!neigh))
577 neigh = __neigh_create(&arp_tbl, &nexthop, dev, false);
578 if (!IS_ERR(neigh)) {
579 sock_confirm_neigh(skb, neigh);
580 ret = neigh_output(neigh, skb);
583 rcu_read_unlock_bh();
585 if (unlikely(ret < 0))
586 vrf_tx_error(skb->dev, skb);
590 static int vrf_output(struct net *net, struct sock *sk, struct sk_buff *skb)
592 struct net_device *dev = skb_dst(skb)->dev;
594 IP_UPD_PO_STATS(net, IPSTATS_MIB_OUT, skb->len);
597 skb->protocol = htons(ETH_P_IP);
599 return NF_HOOK_COND(NFPROTO_IPV4, NF_INET_POST_ROUTING,
600 net, sk, skb, NULL, dev,
602 !(IPCB(skb)->flags & IPSKB_REROUTED));
605 /* set dst on skb to send packet to us via dev_xmit path. Allows
606 * packet to go through device based features such as qdisc, netfilter
607 * hooks and packet sockets with skb->dev set to vrf device.
609 static struct sk_buff *vrf_ip_out(struct net_device *vrf_dev,
613 struct net_vrf *vrf = netdev_priv(vrf_dev);
614 struct dst_entry *dst = NULL;
617 /* don't divert multicast */
618 if (ipv4_is_multicast(ip_hdr(skb)->daddr))
623 rth = rcu_dereference(vrf->rth);
631 if (unlikely(!dst)) {
632 vrf_tx_error(vrf_dev, skb);
637 skb_dst_set(skb, dst);
642 /* called with rcu lock held */
643 static struct sk_buff *vrf_l3_out(struct net_device *vrf_dev,
650 return vrf_ip_out(vrf_dev, sk, skb);
652 return vrf_ip6_out(vrf_dev, sk, skb);
659 static void vrf_rtable_release(struct net_device *dev, struct net_vrf *vrf)
661 struct rtable *rth = rtnl_dereference(vrf->rth);
662 struct rtable *rth_local = rtnl_dereference(vrf->rth_local);
663 struct net *net = dev_net(dev);
664 struct dst_entry *dst;
666 RCU_INIT_POINTER(vrf->rth, NULL);
667 RCU_INIT_POINTER(vrf->rth_local, NULL);
670 /* move dev in dst's to loopback so this VRF device can be deleted
671 * - based on dst_ifdown
676 dst->dev = net->loopback_dev;
682 dst = &rth_local->dst;
684 dst->dev = net->loopback_dev;
690 static int vrf_rtable_create(struct net_device *dev)
692 struct net_vrf *vrf = netdev_priv(dev);
693 struct rtable *rth, *rth_local;
695 if (!fib_new_table(dev_net(dev), vrf->tb_id))
698 /* create a dst for routing packets out through a VRF device */
699 rth = rt_dst_alloc(dev, 0, RTN_UNICAST, 1, 1, 0);
703 /* create a dst for local ingress routing - packets sent locally
704 * to local address via the VRF device as a loopback
706 rth_local = rt_dst_alloc(dev, RTCF_LOCAL, RTN_LOCAL, 1, 1, 0);
708 dst_release(&rth->dst);
712 rth->dst.output = vrf_output;
713 rth->rt_table_id = vrf->tb_id;
715 rth_local->rt_table_id = vrf->tb_id;
717 rcu_assign_pointer(vrf->rth, rth);
718 rcu_assign_pointer(vrf->rth_local, rth_local);
723 /**************************** device handling ********************/
725 /* cycle interface to flush neighbor cache and move routes across tables */
726 static void cycle_netdev(struct net_device *dev)
728 unsigned int flags = dev->flags;
731 if (!netif_running(dev))
734 ret = dev_change_flags(dev, flags & ~IFF_UP);
736 ret = dev_change_flags(dev, flags);
740 "Failed to cycle device %s; route tables might be wrong!\n",
745 static int do_vrf_add_slave(struct net_device *dev, struct net_device *port_dev)
749 ret = netdev_master_upper_dev_link(port_dev, dev, NULL, NULL);
753 port_dev->priv_flags |= IFF_L3MDEV_SLAVE;
754 cycle_netdev(port_dev);
759 static int vrf_add_slave(struct net_device *dev, struct net_device *port_dev)
761 if (netif_is_l3_master(port_dev) || netif_is_l3_slave(port_dev))
764 return do_vrf_add_slave(dev, port_dev);
767 /* inverse of do_vrf_add_slave */
768 static int do_vrf_del_slave(struct net_device *dev, struct net_device *port_dev)
770 netdev_upper_dev_unlink(port_dev, dev);
771 port_dev->priv_flags &= ~IFF_L3MDEV_SLAVE;
773 cycle_netdev(port_dev);
778 static int vrf_del_slave(struct net_device *dev, struct net_device *port_dev)
780 return do_vrf_del_slave(dev, port_dev);
783 static void vrf_dev_uninit(struct net_device *dev)
785 struct net_vrf *vrf = netdev_priv(dev);
786 struct net_device *port_dev;
787 struct list_head *iter;
789 vrf_rtable_release(dev, vrf);
790 vrf_rt6_release(dev, vrf);
792 netdev_for_each_lower_dev(dev, port_dev, iter)
793 vrf_del_slave(dev, port_dev);
795 free_percpu(dev->dstats);
799 static int vrf_dev_init(struct net_device *dev)
801 struct net_vrf *vrf = netdev_priv(dev);
803 dev->dstats = netdev_alloc_pcpu_stats(struct pcpu_dstats);
807 /* create the default dst which points back to us */
808 if (vrf_rtable_create(dev) != 0)
811 if (vrf_rt6_create(dev) != 0)
814 dev->flags = IFF_MASTER | IFF_NOARP;
816 /* MTU is irrelevant for VRF device; set to 64k similar to lo */
817 dev->mtu = 64 * 1024;
819 /* similarly, oper state is irrelevant; set to up to avoid confusion */
820 dev->operstate = IF_OPER_UP;
821 netdev_lockdep_set_classes(dev);
825 vrf_rtable_release(dev, vrf);
827 free_percpu(dev->dstats);
833 static const struct net_device_ops vrf_netdev_ops = {
834 .ndo_init = vrf_dev_init,
835 .ndo_uninit = vrf_dev_uninit,
836 .ndo_start_xmit = vrf_xmit,
837 .ndo_get_stats64 = vrf_get_stats64,
838 .ndo_add_slave = vrf_add_slave,
839 .ndo_del_slave = vrf_del_slave,
842 static u32 vrf_fib_table(const struct net_device *dev)
844 struct net_vrf *vrf = netdev_priv(dev);
849 static int vrf_rcv_finish(struct net *net, struct sock *sk, struct sk_buff *skb)
854 static struct sk_buff *vrf_rcv_nfhook(u8 pf, unsigned int hook,
856 struct net_device *dev)
858 struct net *net = dev_net(dev);
860 if (NF_HOOK(pf, hook, net, NULL, skb, dev, NULL, vrf_rcv_finish) < 0)
861 skb = NULL; /* kfree_skb(skb) handled by nf code */
866 #if IS_ENABLED(CONFIG_IPV6)
867 /* neighbor handling is done with actual device; do not want
868 * to flip skb->dev for those ndisc packets. This really fails
869 * for multiple next protocols (e.g., NEXTHDR_HOP). But it is
872 static bool ipv6_ndisc_frame(const struct sk_buff *skb)
874 const struct ipv6hdr *iph = ipv6_hdr(skb);
877 if (iph->nexthdr == NEXTHDR_ICMP) {
878 const struct icmp6hdr *icmph;
879 struct icmp6hdr _icmph;
881 icmph = skb_header_pointer(skb, sizeof(*iph),
882 sizeof(_icmph), &_icmph);
886 switch (icmph->icmp6_type) {
887 case NDISC_ROUTER_SOLICITATION:
888 case NDISC_ROUTER_ADVERTISEMENT:
889 case NDISC_NEIGHBOUR_SOLICITATION:
890 case NDISC_NEIGHBOUR_ADVERTISEMENT:
901 static struct rt6_info *vrf_ip6_route_lookup(struct net *net,
902 const struct net_device *dev,
907 struct net_vrf *vrf = netdev_priv(dev);
908 struct fib6_table *table = NULL;
909 struct rt6_info *rt6;
913 /* fib6_table does not have a refcnt and can not be freed */
914 rt6 = rcu_dereference(vrf->rt6);
916 table = rt6->rt6i_table;
923 return ip6_pol_route(net, table, ifindex, fl6, flags);
926 static void vrf_ip6_input_dst(struct sk_buff *skb, struct net_device *vrf_dev,
929 const struct ipv6hdr *iph = ipv6_hdr(skb);
930 struct flowi6 fl6 = {
933 .flowlabel = ip6_flowinfo(iph),
934 .flowi6_mark = skb->mark,
935 .flowi6_proto = iph->nexthdr,
936 .flowi6_iif = ifindex,
938 struct net *net = dev_net(vrf_dev);
939 struct rt6_info *rt6;
941 rt6 = vrf_ip6_route_lookup(net, vrf_dev, &fl6, ifindex,
942 RT6_LOOKUP_F_HAS_SADDR | RT6_LOOKUP_F_IFACE);
946 if (unlikely(&rt6->dst == &net->ipv6.ip6_null_entry->dst))
949 skb_dst_set(skb, &rt6->dst);
952 static struct sk_buff *vrf_ip6_rcv(struct net_device *vrf_dev,
955 int orig_iif = skb->skb_iif;
958 /* loopback traffic; do not push through packet taps again.
959 * Reset pkt_type for upper layers to process skb
961 if (skb->pkt_type == PACKET_LOOPBACK) {
963 skb->skb_iif = vrf_dev->ifindex;
964 IP6CB(skb)->flags |= IP6SKB_L3SLAVE;
965 skb->pkt_type = PACKET_HOST;
969 /* if packet is NDISC or addressed to multicast or link-local
970 * then keep the ingress interface
972 need_strict = rt6_need_strict(&ipv6_hdr(skb)->daddr);
973 if (!ipv6_ndisc_frame(skb) && !need_strict) {
974 vrf_rx_stats(vrf_dev, skb->len);
976 skb->skb_iif = vrf_dev->ifindex;
978 skb_push(skb, skb->mac_len);
979 dev_queue_xmit_nit(skb, vrf_dev);
980 skb_pull(skb, skb->mac_len);
982 IP6CB(skb)->flags |= IP6SKB_L3SLAVE;
986 vrf_ip6_input_dst(skb, vrf_dev, orig_iif);
988 skb = vrf_rcv_nfhook(NFPROTO_IPV6, NF_INET_PRE_ROUTING, skb, vrf_dev);
994 static struct sk_buff *vrf_ip6_rcv(struct net_device *vrf_dev,
1001 static struct sk_buff *vrf_ip_rcv(struct net_device *vrf_dev,
1002 struct sk_buff *skb)
1005 skb->skb_iif = vrf_dev->ifindex;
1006 IPCB(skb)->flags |= IPSKB_L3SLAVE;
1008 if (ipv4_is_multicast(ip_hdr(skb)->daddr))
1011 /* loopback traffic; do not push through packet taps again.
1012 * Reset pkt_type for upper layers to process skb
1014 if (skb->pkt_type == PACKET_LOOPBACK) {
1015 skb->pkt_type = PACKET_HOST;
1019 vrf_rx_stats(vrf_dev, skb->len);
1021 skb_push(skb, skb->mac_len);
1022 dev_queue_xmit_nit(skb, vrf_dev);
1023 skb_pull(skb, skb->mac_len);
1025 skb = vrf_rcv_nfhook(NFPROTO_IPV4, NF_INET_PRE_ROUTING, skb, vrf_dev);
1030 /* called with rcu lock held */
1031 static struct sk_buff *vrf_l3_rcv(struct net_device *vrf_dev,
1032 struct sk_buff *skb,
1037 return vrf_ip_rcv(vrf_dev, skb);
1039 return vrf_ip6_rcv(vrf_dev, skb);
1045 #if IS_ENABLED(CONFIG_IPV6)
1046 /* send to link-local or multicast address via interface enslaved to
1047 * VRF device. Force lookup to VRF table without changing flow struct
1049 static struct dst_entry *vrf_link_scope_lookup(const struct net_device *dev,
1052 struct net *net = dev_net(dev);
1053 int flags = RT6_LOOKUP_F_IFACE;
1054 struct dst_entry *dst = NULL;
1055 struct rt6_info *rt;
1057 /* VRF device does not have a link-local address and
1058 * sending packets to link-local or mcast addresses over
1059 * a VRF device does not make sense
1061 if (fl6->flowi6_oif == dev->ifindex) {
1062 dst = &net->ipv6.ip6_null_entry->dst;
1067 if (!ipv6_addr_any(&fl6->saddr))
1068 flags |= RT6_LOOKUP_F_HAS_SADDR;
1070 rt = vrf_ip6_route_lookup(net, dev, fl6, fl6->flowi6_oif, flags);
1078 static const struct l3mdev_ops vrf_l3mdev_ops = {
1079 .l3mdev_fib_table = vrf_fib_table,
1080 .l3mdev_l3_rcv = vrf_l3_rcv,
1081 .l3mdev_l3_out = vrf_l3_out,
1082 #if IS_ENABLED(CONFIG_IPV6)
1083 .l3mdev_link_scope_lookup = vrf_link_scope_lookup,
1087 static void vrf_get_drvinfo(struct net_device *dev,
1088 struct ethtool_drvinfo *info)
1090 strlcpy(info->driver, DRV_NAME, sizeof(info->driver));
1091 strlcpy(info->version, DRV_VERSION, sizeof(info->version));
1094 static const struct ethtool_ops vrf_ethtool_ops = {
1095 .get_drvinfo = vrf_get_drvinfo,
1098 static inline size_t vrf_fib_rule_nl_size(void)
1102 sz = NLMSG_ALIGN(sizeof(struct fib_rule_hdr));
1103 sz += nla_total_size(sizeof(u8)); /* FRA_L3MDEV */
1104 sz += nla_total_size(sizeof(u32)); /* FRA_PRIORITY */
1109 static int vrf_fib_rule(const struct net_device *dev, __u8 family, bool add_it)
1111 struct fib_rule_hdr *frh;
1112 struct nlmsghdr *nlh;
1113 struct sk_buff *skb;
1116 if (family == AF_INET6 && !ipv6_mod_enabled())
1119 skb = nlmsg_new(vrf_fib_rule_nl_size(), GFP_KERNEL);
1123 nlh = nlmsg_put(skb, 0, 0, 0, sizeof(*frh), 0);
1125 goto nla_put_failure;
1127 /* rule only needs to appear once */
1128 nlh->nlmsg_flags &= NLM_F_EXCL;
1130 frh = nlmsg_data(nlh);
1131 memset(frh, 0, sizeof(*frh));
1132 frh->family = family;
1133 frh->action = FR_ACT_TO_TBL;
1135 if (nla_put_u32(skb, FRA_L3MDEV, 1))
1136 goto nla_put_failure;
1138 if (nla_put_u32(skb, FRA_PRIORITY, FIB_RULE_PREF))
1139 goto nla_put_failure;
1141 nlmsg_end(skb, nlh);
1143 /* fib_nl_{new,del}rule handling looks for net from skb->sk */
1144 skb->sk = dev_net(dev)->rtnl;
1146 err = fib_nl_newrule(skb, nlh);
1150 err = fib_nl_delrule(skb, nlh);
1164 static int vrf_add_fib_rules(const struct net_device *dev)
1168 err = vrf_fib_rule(dev, AF_INET, true);
1172 err = vrf_fib_rule(dev, AF_INET6, true);
1176 #if IS_ENABLED(CONFIG_IP_MROUTE_MULTIPLE_TABLES)
1177 err = vrf_fib_rule(dev, RTNL_FAMILY_IPMR, true);
1184 #if IS_ENABLED(CONFIG_IP_MROUTE_MULTIPLE_TABLES)
1186 vrf_fib_rule(dev, AF_INET6, false);
1190 vrf_fib_rule(dev, AF_INET, false);
1193 netdev_err(dev, "Failed to add FIB rules.\n");
1197 static void vrf_setup(struct net_device *dev)
1201 /* Initialize the device structure. */
1202 dev->netdev_ops = &vrf_netdev_ops;
1203 dev->l3mdev_ops = &vrf_l3mdev_ops;
1204 dev->ethtool_ops = &vrf_ethtool_ops;
1205 dev->destructor = free_netdev;
1207 /* Fill in device structure with ethernet-generic values. */
1208 eth_hw_addr_random(dev);
1210 /* don't acquire vrf device's netif_tx_lock when transmitting */
1211 dev->features |= NETIF_F_LLTX;
1213 /* don't allow vrf devices to change network namespaces. */
1214 dev->features |= NETIF_F_NETNS_LOCAL;
1216 /* does not make sense for a VLAN to be added to a vrf device */
1217 dev->features |= NETIF_F_VLAN_CHALLENGED;
1219 /* enable offload features */
1220 dev->features |= NETIF_F_GSO_SOFTWARE;
1221 dev->features |= NETIF_F_RXCSUM | NETIF_F_HW_CSUM;
1222 dev->features |= NETIF_F_SG | NETIF_F_FRAGLIST | NETIF_F_HIGHDMA;
1224 dev->hw_features = dev->features;
1225 dev->hw_enc_features = dev->features;
1227 /* default to no qdisc; user can add if desired */
1228 dev->priv_flags |= IFF_NO_QUEUE;
1231 static int vrf_validate(struct nlattr *tb[], struct nlattr *data[])
1233 if (tb[IFLA_ADDRESS]) {
1234 if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
1236 if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
1237 return -EADDRNOTAVAIL;
1242 static void vrf_dellink(struct net_device *dev, struct list_head *head)
1244 unregister_netdevice_queue(dev, head);
1247 static int vrf_newlink(struct net *src_net, struct net_device *dev,
1248 struct nlattr *tb[], struct nlattr *data[])
1250 struct net_vrf *vrf = netdev_priv(dev);
1253 if (!data || !data[IFLA_VRF_TABLE])
1256 vrf->tb_id = nla_get_u32(data[IFLA_VRF_TABLE]);
1257 if (vrf->tb_id == RT_TABLE_UNSPEC)
1260 dev->priv_flags |= IFF_L3MDEV_MASTER;
1262 err = register_netdevice(dev);
1266 if (add_fib_rules) {
1267 err = vrf_add_fib_rules(dev);
1269 unregister_netdevice(dev);
1272 add_fib_rules = false;
1279 static size_t vrf_nl_getsize(const struct net_device *dev)
1281 return nla_total_size(sizeof(u32)); /* IFLA_VRF_TABLE */
1284 static int vrf_fillinfo(struct sk_buff *skb,
1285 const struct net_device *dev)
1287 struct net_vrf *vrf = netdev_priv(dev);
1289 return nla_put_u32(skb, IFLA_VRF_TABLE, vrf->tb_id);
1292 static size_t vrf_get_slave_size(const struct net_device *bond_dev,
1293 const struct net_device *slave_dev)
1295 return nla_total_size(sizeof(u32)); /* IFLA_VRF_PORT_TABLE */
1298 static int vrf_fill_slave_info(struct sk_buff *skb,
1299 const struct net_device *vrf_dev,
1300 const struct net_device *slave_dev)
1302 struct net_vrf *vrf = netdev_priv(vrf_dev);
1304 if (nla_put_u32(skb, IFLA_VRF_PORT_TABLE, vrf->tb_id))
1310 static const struct nla_policy vrf_nl_policy[IFLA_VRF_MAX + 1] = {
1311 [IFLA_VRF_TABLE] = { .type = NLA_U32 },
1314 static struct rtnl_link_ops vrf_link_ops __read_mostly = {
1316 .priv_size = sizeof(struct net_vrf),
1318 .get_size = vrf_nl_getsize,
1319 .policy = vrf_nl_policy,
1320 .validate = vrf_validate,
1321 .fill_info = vrf_fillinfo,
1323 .get_slave_size = vrf_get_slave_size,
1324 .fill_slave_info = vrf_fill_slave_info,
1326 .newlink = vrf_newlink,
1327 .dellink = vrf_dellink,
1329 .maxtype = IFLA_VRF_MAX,
1332 static int vrf_device_event(struct notifier_block *unused,
1333 unsigned long event, void *ptr)
1335 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
1337 /* only care about unregister events to drop slave references */
1338 if (event == NETDEV_UNREGISTER) {
1339 struct net_device *vrf_dev;
1341 if (!netif_is_l3_slave(dev))
1344 vrf_dev = netdev_master_upper_dev_get(dev);
1345 vrf_del_slave(vrf_dev, dev);
1351 static struct notifier_block vrf_notifier_block __read_mostly = {
1352 .notifier_call = vrf_device_event,
1355 static int __init vrf_init_module(void)
1359 register_netdevice_notifier(&vrf_notifier_block);
1361 rc = rtnl_link_register(&vrf_link_ops);
1368 unregister_netdevice_notifier(&vrf_notifier_block);
1372 module_init(vrf_init_module);
1373 MODULE_AUTHOR("Shrijeet Mukherjee, David Ahern");
1374 MODULE_DESCRIPTION("Device driver to instantiate VRF domains");
1375 MODULE_LICENSE("GPL");
1376 MODULE_ALIAS_RTNL_LINK(DRV_NAME);
1377 MODULE_VERSION(DRV_VERSION);