2 * vrf.c: device driver to encapsulate a VRF space
4 * Copyright (c) 2015 Cumulus Networks. All rights reserved.
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>
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;
49 struct rtable __rcu *rth;
50 struct rt6_info __rcu *rt6;
51 #if IS_ENABLED(CONFIG_IPV6)
52 struct fib6_table *fib6_table;
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);
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++;
83 static void vrf_get_stats64(struct net_device *dev,
84 struct rtnl_link_stats64 *stats)
88 for_each_possible_cpu(i) {
89 const struct pcpu_dstats *dstats;
90 u64 tbytes, tpkts, tdrops, rbytes, rpkts;
93 dstats = per_cpu_ptr(dev->dstats, i);
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;
118 if (dev->num_tx_queues > 1)
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)
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);
149 this_cpu_inc(dev->dstats->rx_drps);
154 #if IS_ENABLED(CONFIG_IPV6)
155 static int vrf_ip6_local_out(struct net *net, struct sock *sk,
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);
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,
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);
195 /* if dst.dev is loopback or the VRF device again this is locally
196 * originated traffic destined to a local address. Short circuit
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++;
211 ret = NET_XMIT_SUCCESS;
215 vrf_tx_error(dev, skb);
216 return NET_XMIT_DROP;
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;
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,
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);
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);
259 rt = ip_route_output_flow(net, &fl4, NULL);
265 /* if dst.dev is loopback or the VRF device again this is locally
266 * originated traffic destined to a local address. Short circuit
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));
278 ip4h->saddr = inet_select_addr(skb_dst(skb)->dev, 0,
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++;
286 ret = NET_XMIT_SUCCESS;
291 vrf_tx_error(vrf_dev, skb);
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);
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)
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);
318 dstats->tx_bytes += len;
319 u64_stats_update_end(&dstats->syncp);
321 this_cpu_inc(dev->dstats->tx_drps);
327 static int vrf_finish_direct(struct net *net, struct sock *sk,
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;
341 dev_queue_xmit_nit(skb, vrf_dev);
342 rcu_read_unlock_bh();
344 skb_pull(skb, ETH_HLEN);
350 #if IS_ENABLED(CONFIG_IPV6)
351 /* modelled after ip6_finish_output2 */
352 static int vrf_finish_output6(struct net *net, struct sock *sk,
355 struct dst_entry *dst = skb_dst(skb);
356 struct net_device *dev = dst->dev;
357 struct neighbour *neigh;
358 struct in6_addr *nexthop;
363 skb->protocol = htons(ETH_P_IPV6);
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, false);
374 rcu_read_unlock_bh();
377 rcu_read_unlock_bh();
379 IP6_INC_STATS(dev_net(dst->dev),
380 ip6_dst_idev(dst), IPSTATS_MIB_OUTNOROUTES);
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,
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,
401 struct net_vrf *vrf = netdev_priv(vrf_dev);
402 struct dst_entry *dst = NULL;
403 struct rt6_info *rt6;
407 rt6 = rcu_dereference(vrf->rt6);
415 if (unlikely(!dst)) {
416 vrf_tx_error(vrf_dev, skb);
421 skb_dst_set(skb, dst);
426 static int vrf_output6_direct(struct net *net, struct sock *sk,
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,
434 !(IPCB(skb)->flags & IPSKB_REROUTED));
437 static struct sk_buff *vrf_ip6_out_direct(struct net_device *vrf_dev,
441 struct net *net = dev_net(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))
461 static struct sk_buff *vrf_ip6_out(struct net_device *vrf_dev,
465 /* don't divert link scope packets */
466 if (rt6_need_strict(&ipv6_hdr(skb)->daddr))
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);
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);
485 /* move dev in dst's to loopback so this VRF device can be deleted
486 * - based on dst_ifdown
491 dst->dev = net->loopback_dev;
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;
505 /* IPv6 can be CONFIG enabled and then disabled runtime */
506 if (!ipv6_mod_enabled())
509 vrf->fib6_table = fib6_new_table(net, vrf->tb_id);
510 if (!vrf->fib6_table)
513 /* create a dst for routing packets out a VRF device */
514 rt6 = ip6_dst_alloc(net, dev, flags);
518 rt6->dst.output = vrf_output6;
520 rcu_assign_pointer(vrf->rt6, rt6);
527 static struct sk_buff *vrf_ip6_out(struct net_device *vrf_dev,
534 static void vrf_rt6_release(struct net_device *dev, struct net_vrf *vrf)
538 static int vrf_rt6_create(struct net_device *dev)
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 bool is_v6gw = false;
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));
567 skb_set_owner_w(skb2, skb->sk);
575 neigh = ip_neigh_for_gw(rt, skb, &is_v6gw);
576 if (!IS_ERR(neigh)) {
577 sock_confirm_neigh(skb, neigh);
578 /* if crossing protocols, can not use the cached header */
579 ret = neigh_output(neigh, skb, is_v6gw);
580 rcu_read_unlock_bh();
584 rcu_read_unlock_bh();
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_redirect(struct net_device *vrf_dev,
612 struct net_vrf *vrf = netdev_priv(vrf_dev);
613 struct dst_entry *dst = NULL;
618 rth = rcu_dereference(vrf->rth);
626 if (unlikely(!dst)) {
627 vrf_tx_error(vrf_dev, skb);
632 skb_dst_set(skb, dst);
637 static int vrf_output_direct(struct net *net, struct sock *sk,
640 skb->protocol = htons(ETH_P_IP);
642 return NF_HOOK_COND(NFPROTO_IPV4, NF_INET_POST_ROUTING,
643 net, sk, skb, NULL, skb->dev,
645 !(IPCB(skb)->flags & IPSKB_REROUTED));
648 static struct sk_buff *vrf_ip_out_direct(struct net_device *vrf_dev,
652 struct net *net = dev_net(vrf_dev);
657 err = nf_hook(NFPROTO_IPV4, NF_INET_LOCAL_OUT, net, sk,
658 skb, NULL, vrf_dev, vrf_output_direct);
660 if (likely(err == 1))
661 err = vrf_output_direct(net, sk, skb);
663 /* reset skb device */
664 if (likely(err == 1))
672 static struct sk_buff *vrf_ip_out(struct net_device *vrf_dev,
676 /* don't divert multicast or local broadcast */
677 if (ipv4_is_multicast(ip_hdr(skb)->daddr) ||
678 ipv4_is_lbcast(ip_hdr(skb)->daddr))
681 if (qdisc_tx_is_default(vrf_dev))
682 return vrf_ip_out_direct(vrf_dev, sk, skb);
684 return vrf_ip_out_redirect(vrf_dev, skb);
687 /* called with rcu lock held */
688 static struct sk_buff *vrf_l3_out(struct net_device *vrf_dev,
695 return vrf_ip_out(vrf_dev, sk, skb);
697 return vrf_ip6_out(vrf_dev, sk, skb);
704 static void vrf_rtable_release(struct net_device *dev, struct net_vrf *vrf)
706 struct rtable *rth = rtnl_dereference(vrf->rth);
707 struct net *net = dev_net(dev);
708 struct dst_entry *dst;
710 RCU_INIT_POINTER(vrf->rth, NULL);
713 /* move dev in dst's to loopback so this VRF device can be deleted
714 * - based on dst_ifdown
719 dst->dev = net->loopback_dev;
725 static int vrf_rtable_create(struct net_device *dev)
727 struct net_vrf *vrf = netdev_priv(dev);
730 if (!fib_new_table(dev_net(dev), vrf->tb_id))
733 /* create a dst for routing packets out through a VRF device */
734 rth = rt_dst_alloc(dev, 0, RTN_UNICAST, 1, 1, 0);
738 rth->dst.output = vrf_output;
740 rcu_assign_pointer(vrf->rth, rth);
745 /**************************** device handling ********************/
747 /* cycle interface to flush neighbor cache and move routes across tables */
748 static void cycle_netdev(struct net_device *dev,
749 struct netlink_ext_ack *extack)
751 unsigned int flags = dev->flags;
754 if (!netif_running(dev))
757 ret = dev_change_flags(dev, flags & ~IFF_UP, extack);
759 ret = dev_change_flags(dev, flags, extack);
763 "Failed to cycle device %s; route tables might be wrong!\n",
768 static int do_vrf_add_slave(struct net_device *dev, struct net_device *port_dev,
769 struct netlink_ext_ack *extack)
773 /* do not allow loopback device to be enslaved to a VRF.
774 * The vrf device acts as the loopback for the vrf.
776 if (port_dev == dev_net(dev)->loopback_dev) {
777 NL_SET_ERR_MSG(extack,
778 "Can not enslave loopback device to a VRF");
782 port_dev->priv_flags |= IFF_L3MDEV_SLAVE;
783 ret = netdev_master_upper_dev_link(port_dev, dev, NULL, NULL, extack);
787 cycle_netdev(port_dev, extack);
792 port_dev->priv_flags &= ~IFF_L3MDEV_SLAVE;
796 static int vrf_add_slave(struct net_device *dev, struct net_device *port_dev,
797 struct netlink_ext_ack *extack)
799 if (netif_is_l3_master(port_dev)) {
800 NL_SET_ERR_MSG(extack,
801 "Can not enslave an L3 master device to a VRF");
805 if (netif_is_l3_slave(port_dev))
808 return do_vrf_add_slave(dev, port_dev, extack);
811 /* inverse of do_vrf_add_slave */
812 static int do_vrf_del_slave(struct net_device *dev, struct net_device *port_dev)
814 netdev_upper_dev_unlink(port_dev, dev);
815 port_dev->priv_flags &= ~IFF_L3MDEV_SLAVE;
817 cycle_netdev(port_dev, NULL);
822 static int vrf_del_slave(struct net_device *dev, struct net_device *port_dev)
824 return do_vrf_del_slave(dev, port_dev);
827 static void vrf_dev_uninit(struct net_device *dev)
829 struct net_vrf *vrf = netdev_priv(dev);
831 vrf_rtable_release(dev, vrf);
832 vrf_rt6_release(dev, vrf);
834 free_percpu(dev->dstats);
838 static int vrf_dev_init(struct net_device *dev)
840 struct net_vrf *vrf = netdev_priv(dev);
842 dev->dstats = netdev_alloc_pcpu_stats(struct pcpu_dstats);
846 /* create the default dst which points back to us */
847 if (vrf_rtable_create(dev) != 0)
850 if (vrf_rt6_create(dev) != 0)
853 dev->flags = IFF_MASTER | IFF_NOARP;
855 /* MTU is irrelevant for VRF device; set to 64k similar to lo */
856 dev->mtu = 64 * 1024;
858 /* similarly, oper state is irrelevant; set to up to avoid confusion */
859 dev->operstate = IF_OPER_UP;
860 netdev_lockdep_set_classes(dev);
864 vrf_rtable_release(dev, vrf);
866 free_percpu(dev->dstats);
872 static const struct net_device_ops vrf_netdev_ops = {
873 .ndo_init = vrf_dev_init,
874 .ndo_uninit = vrf_dev_uninit,
875 .ndo_start_xmit = vrf_xmit,
876 .ndo_set_mac_address = eth_mac_addr,
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);
889 static int vrf_rcv_finish(struct net *net, struct sock *sk, struct sk_buff *skb)
895 static struct sk_buff *vrf_rcv_nfhook(u8 pf, unsigned int hook,
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 */
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
913 static bool ipv6_ndisc_frame(const struct sk_buff *skb)
915 const struct ipv6hdr *iph = ipv6_hdr(skb);
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);
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:
942 static struct rt6_info *vrf_ip6_route_lookup(struct net *net,
943 const struct net_device *dev,
946 const struct sk_buff *skb,
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,
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,
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);
974 if (unlikely(&rt6->dst == &net->ipv6.ip6_null_entry->dst))
977 skb_dst_set(skb, &rt6->dst);
980 static struct sk_buff *vrf_ip6_rcv(struct net_device *vrf_dev,
983 int orig_iif = skb->skb_iif;
984 bool need_strict = rt6_need_strict(&ipv6_hdr(skb)->daddr);
985 bool is_ndisc = ipv6_ndisc_frame(skb);
987 /* loopback, multicast & non-ND link-local traffic; do not push through
988 * packet taps again. Reset pkt_type for upper layers to process skb
990 if (skb->pkt_type == PACKET_LOOPBACK || (need_strict && !is_ndisc)) {
992 skb->skb_iif = vrf_dev->ifindex;
993 IP6CB(skb)->flags |= IP6SKB_L3SLAVE;
994 if (skb->pkt_type == PACKET_LOOPBACK)
995 skb->pkt_type = PACKET_HOST;
999 /* if packet is NDISC then keep the ingress interface */
1001 vrf_rx_stats(vrf_dev, skb->len);
1003 skb->skb_iif = vrf_dev->ifindex;
1005 if (!list_empty(&vrf_dev->ptype_all)) {
1006 skb_push(skb, skb->mac_len);
1007 dev_queue_xmit_nit(skb, vrf_dev);
1008 skb_pull(skb, skb->mac_len);
1011 IP6CB(skb)->flags |= IP6SKB_L3SLAVE;
1015 vrf_ip6_input_dst(skb, vrf_dev, orig_iif);
1017 skb = vrf_rcv_nfhook(NFPROTO_IPV6, NF_INET_PRE_ROUTING, skb, vrf_dev);
1023 static struct sk_buff *vrf_ip6_rcv(struct net_device *vrf_dev,
1024 struct sk_buff *skb)
1030 static struct sk_buff *vrf_ip_rcv(struct net_device *vrf_dev,
1031 struct sk_buff *skb)
1034 skb->skb_iif = vrf_dev->ifindex;
1035 IPCB(skb)->flags |= IPSKB_L3SLAVE;
1037 if (ipv4_is_multicast(ip_hdr(skb)->daddr))
1040 /* loopback traffic; do not push through packet taps again.
1041 * Reset pkt_type for upper layers to process skb
1043 if (skb->pkt_type == PACKET_LOOPBACK) {
1044 skb->pkt_type = PACKET_HOST;
1048 vrf_rx_stats(vrf_dev, skb->len);
1050 if (!list_empty(&vrf_dev->ptype_all)) {
1051 skb_push(skb, skb->mac_len);
1052 dev_queue_xmit_nit(skb, vrf_dev);
1053 skb_pull(skb, skb->mac_len);
1056 skb = vrf_rcv_nfhook(NFPROTO_IPV4, NF_INET_PRE_ROUTING, skb, vrf_dev);
1061 /* called with rcu lock held */
1062 static struct sk_buff *vrf_l3_rcv(struct net_device *vrf_dev,
1063 struct sk_buff *skb,
1068 return vrf_ip_rcv(vrf_dev, skb);
1070 return vrf_ip6_rcv(vrf_dev, skb);
1076 #if IS_ENABLED(CONFIG_IPV6)
1077 /* send to link-local or multicast address via interface enslaved to
1078 * VRF device. Force lookup to VRF table without changing flow struct
1080 static struct dst_entry *vrf_link_scope_lookup(const struct net_device *dev,
1083 struct net *net = dev_net(dev);
1084 int flags = RT6_LOOKUP_F_IFACE;
1085 struct dst_entry *dst = NULL;
1086 struct rt6_info *rt;
1088 /* VRF device does not have a link-local address and
1089 * sending packets to link-local or mcast addresses over
1090 * a VRF device does not make sense
1092 if (fl6->flowi6_oif == dev->ifindex) {
1093 dst = &net->ipv6.ip6_null_entry->dst;
1098 if (!ipv6_addr_any(&fl6->saddr))
1099 flags |= RT6_LOOKUP_F_HAS_SADDR;
1101 rt = vrf_ip6_route_lookup(net, dev, fl6, fl6->flowi6_oif, NULL, flags);
1109 static const struct l3mdev_ops vrf_l3mdev_ops = {
1110 .l3mdev_fib_table = vrf_fib_table,
1111 .l3mdev_l3_rcv = vrf_l3_rcv,
1112 .l3mdev_l3_out = vrf_l3_out,
1113 #if IS_ENABLED(CONFIG_IPV6)
1114 .l3mdev_link_scope_lookup = vrf_link_scope_lookup,
1118 static void vrf_get_drvinfo(struct net_device *dev,
1119 struct ethtool_drvinfo *info)
1121 strlcpy(info->driver, DRV_NAME, sizeof(info->driver));
1122 strlcpy(info->version, DRV_VERSION, sizeof(info->version));
1125 static const struct ethtool_ops vrf_ethtool_ops = {
1126 .get_drvinfo = vrf_get_drvinfo,
1129 static inline size_t vrf_fib_rule_nl_size(void)
1133 sz = NLMSG_ALIGN(sizeof(struct fib_rule_hdr));
1134 sz += nla_total_size(sizeof(u8)); /* FRA_L3MDEV */
1135 sz += nla_total_size(sizeof(u32)); /* FRA_PRIORITY */
1136 sz += nla_total_size(sizeof(u8)); /* FRA_PROTOCOL */
1141 static int vrf_fib_rule(const struct net_device *dev, __u8 family, bool add_it)
1143 struct fib_rule_hdr *frh;
1144 struct nlmsghdr *nlh;
1145 struct sk_buff *skb;
1148 if (family == AF_INET6 && !ipv6_mod_enabled())
1151 skb = nlmsg_new(vrf_fib_rule_nl_size(), GFP_KERNEL);
1155 nlh = nlmsg_put(skb, 0, 0, 0, sizeof(*frh), 0);
1157 goto nla_put_failure;
1159 /* rule only needs to appear once */
1160 nlh->nlmsg_flags |= NLM_F_EXCL;
1162 frh = nlmsg_data(nlh);
1163 memset(frh, 0, sizeof(*frh));
1164 frh->family = family;
1165 frh->action = FR_ACT_TO_TBL;
1167 if (nla_put_u8(skb, FRA_PROTOCOL, RTPROT_KERNEL))
1168 goto nla_put_failure;
1170 if (nla_put_u8(skb, FRA_L3MDEV, 1))
1171 goto nla_put_failure;
1173 if (nla_put_u32(skb, FRA_PRIORITY, FIB_RULE_PREF))
1174 goto nla_put_failure;
1176 nlmsg_end(skb, nlh);
1178 /* fib_nl_{new,del}rule handling looks for net from skb->sk */
1179 skb->sk = dev_net(dev)->rtnl;
1181 err = fib_nl_newrule(skb, nlh, NULL);
1185 err = fib_nl_delrule(skb, nlh, NULL);
1199 static int vrf_add_fib_rules(const struct net_device *dev)
1203 err = vrf_fib_rule(dev, AF_INET, true);
1207 err = vrf_fib_rule(dev, AF_INET6, true);
1211 #if IS_ENABLED(CONFIG_IP_MROUTE_MULTIPLE_TABLES)
1212 err = vrf_fib_rule(dev, RTNL_FAMILY_IPMR, true);
1217 #if IS_ENABLED(CONFIG_IPV6_MROUTE_MULTIPLE_TABLES)
1218 err = vrf_fib_rule(dev, RTNL_FAMILY_IP6MR, true);
1225 #if IS_ENABLED(CONFIG_IPV6_MROUTE_MULTIPLE_TABLES)
1227 vrf_fib_rule(dev, RTNL_FAMILY_IPMR, false);
1230 #if IS_ENABLED(CONFIG_IP_MROUTE_MULTIPLE_TABLES)
1232 vrf_fib_rule(dev, AF_INET6, false);
1236 vrf_fib_rule(dev, AF_INET, false);
1239 netdev_err(dev, "Failed to add FIB rules.\n");
1243 static void vrf_setup(struct net_device *dev)
1247 /* Initialize the device structure. */
1248 dev->netdev_ops = &vrf_netdev_ops;
1249 dev->l3mdev_ops = &vrf_l3mdev_ops;
1250 dev->ethtool_ops = &vrf_ethtool_ops;
1251 dev->needs_free_netdev = true;
1253 /* Fill in device structure with ethernet-generic values. */
1254 eth_hw_addr_random(dev);
1256 /* don't acquire vrf device's netif_tx_lock when transmitting */
1257 dev->features |= NETIF_F_LLTX;
1259 /* don't allow vrf devices to change network namespaces. */
1260 dev->features |= NETIF_F_NETNS_LOCAL;
1262 /* does not make sense for a VLAN to be added to a vrf device */
1263 dev->features |= NETIF_F_VLAN_CHALLENGED;
1265 /* enable offload features */
1266 dev->features |= NETIF_F_GSO_SOFTWARE;
1267 dev->features |= NETIF_F_RXCSUM | NETIF_F_HW_CSUM | NETIF_F_SCTP_CRC;
1268 dev->features |= NETIF_F_SG | NETIF_F_FRAGLIST | NETIF_F_HIGHDMA;
1270 dev->hw_features = dev->features;
1271 dev->hw_enc_features = dev->features;
1273 /* default to no qdisc; user can add if desired */
1274 dev->priv_flags |= IFF_NO_QUEUE;
1275 dev->priv_flags |= IFF_NO_RX_HANDLER;
1276 dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1278 /* VRF devices do not care about MTU, but if the MTU is set
1279 * too low then the ipv4 and ipv6 protocols are disabled
1280 * which breaks networking.
1282 dev->min_mtu = IPV6_MIN_MTU;
1283 dev->max_mtu = ETH_MAX_MTU;
1286 static int vrf_validate(struct nlattr *tb[], struct nlattr *data[],
1287 struct netlink_ext_ack *extack)
1289 if (tb[IFLA_ADDRESS]) {
1290 if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN) {
1291 NL_SET_ERR_MSG(extack, "Invalid hardware address");
1294 if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS]))) {
1295 NL_SET_ERR_MSG(extack, "Invalid hardware address");
1296 return -EADDRNOTAVAIL;
1302 static void vrf_dellink(struct net_device *dev, struct list_head *head)
1304 struct net_device *port_dev;
1305 struct list_head *iter;
1307 netdev_for_each_lower_dev(dev, port_dev, iter)
1308 vrf_del_slave(dev, port_dev);
1310 unregister_netdevice_queue(dev, head);
1313 static int vrf_newlink(struct net *src_net, struct net_device *dev,
1314 struct nlattr *tb[], struct nlattr *data[],
1315 struct netlink_ext_ack *extack)
1317 struct net_vrf *vrf = netdev_priv(dev);
1318 bool *add_fib_rules;
1322 if (!data || !data[IFLA_VRF_TABLE]) {
1323 NL_SET_ERR_MSG(extack, "VRF table id is missing");
1327 vrf->tb_id = nla_get_u32(data[IFLA_VRF_TABLE]);
1328 if (vrf->tb_id == RT_TABLE_UNSPEC) {
1329 NL_SET_ERR_MSG_ATTR(extack, data[IFLA_VRF_TABLE],
1330 "Invalid VRF table id");
1334 dev->priv_flags |= IFF_L3MDEV_MASTER;
1336 err = register_netdevice(dev);
1341 add_fib_rules = net_generic(net, vrf_net_id);
1342 if (*add_fib_rules) {
1343 err = vrf_add_fib_rules(dev);
1345 unregister_netdevice(dev);
1348 *add_fib_rules = false;
1355 static size_t vrf_nl_getsize(const struct net_device *dev)
1357 return nla_total_size(sizeof(u32)); /* IFLA_VRF_TABLE */
1360 static int vrf_fillinfo(struct sk_buff *skb,
1361 const struct net_device *dev)
1363 struct net_vrf *vrf = netdev_priv(dev);
1365 return nla_put_u32(skb, IFLA_VRF_TABLE, vrf->tb_id);
1368 static size_t vrf_get_slave_size(const struct net_device *bond_dev,
1369 const struct net_device *slave_dev)
1371 return nla_total_size(sizeof(u32)); /* IFLA_VRF_PORT_TABLE */
1374 static int vrf_fill_slave_info(struct sk_buff *skb,
1375 const struct net_device *vrf_dev,
1376 const struct net_device *slave_dev)
1378 struct net_vrf *vrf = netdev_priv(vrf_dev);
1380 if (nla_put_u32(skb, IFLA_VRF_PORT_TABLE, vrf->tb_id))
1386 static const struct nla_policy vrf_nl_policy[IFLA_VRF_MAX + 1] = {
1387 [IFLA_VRF_TABLE] = { .type = NLA_U32 },
1390 static struct rtnl_link_ops vrf_link_ops __read_mostly = {
1392 .priv_size = sizeof(struct net_vrf),
1394 .get_size = vrf_nl_getsize,
1395 .policy = vrf_nl_policy,
1396 .validate = vrf_validate,
1397 .fill_info = vrf_fillinfo,
1399 .get_slave_size = vrf_get_slave_size,
1400 .fill_slave_info = vrf_fill_slave_info,
1402 .newlink = vrf_newlink,
1403 .dellink = vrf_dellink,
1405 .maxtype = IFLA_VRF_MAX,
1408 static int vrf_device_event(struct notifier_block *unused,
1409 unsigned long event, void *ptr)
1411 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
1413 /* only care about unregister events to drop slave references */
1414 if (event == NETDEV_UNREGISTER) {
1415 struct net_device *vrf_dev;
1417 if (!netif_is_l3_slave(dev))
1420 vrf_dev = netdev_master_upper_dev_get(dev);
1421 vrf_del_slave(vrf_dev, dev);
1427 static struct notifier_block vrf_notifier_block __read_mostly = {
1428 .notifier_call = vrf_device_event,
1431 /* Initialize per network namespace state */
1432 static int __net_init vrf_netns_init(struct net *net)
1434 bool *add_fib_rules = net_generic(net, vrf_net_id);
1436 *add_fib_rules = true;
1441 static struct pernet_operations vrf_net_ops __net_initdata = {
1442 .init = vrf_netns_init,
1444 .size = sizeof(bool),
1447 static int __init vrf_init_module(void)
1451 register_netdevice_notifier(&vrf_notifier_block);
1453 rc = register_pernet_subsys(&vrf_net_ops);
1457 rc = rtnl_link_register(&vrf_link_ops);
1459 unregister_pernet_subsys(&vrf_net_ops);
1466 unregister_netdevice_notifier(&vrf_notifier_block);
1470 module_init(vrf_init_module);
1471 MODULE_AUTHOR("Shrijeet Mukherjee, David Ahern");
1472 MODULE_DESCRIPTION("Device driver to instantiate VRF domains");
1473 MODULE_LICENSE("GPL");
1474 MODULE_ALIAS_RTNL_LINK(DRV_NAME);
1475 MODULE_VERSION(DRV_VERSION);