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 struct rtnl_link_stats64 *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;
108 /* Local traffic destined to local address. Reinsert the packet to rx
109 * path, similar to loopback handling.
111 static int vrf_local_xmit(struct sk_buff *skb, struct net_device *dev,
112 struct dst_entry *dst)
118 skb_dst_set(skb, dst);
121 /* set pkt_type to avoid skb hitting packet taps twice -
122 * once on Tx and again in Rx processing
124 skb->pkt_type = PACKET_LOOPBACK;
126 skb->protocol = eth_type_trans(skb, dev);
128 if (likely(netif_rx(skb) == NET_RX_SUCCESS))
129 vrf_rx_stats(dev, len);
131 this_cpu_inc(dev->dstats->rx_drps);
136 #if IS_ENABLED(CONFIG_IPV6)
137 static int vrf_ip6_local_out(struct net *net, struct sock *sk,
142 err = nf_hook(NFPROTO_IPV6, NF_INET_LOCAL_OUT, net,
143 sk, skb, NULL, skb_dst(skb)->dev, dst_output);
145 if (likely(err == 1))
146 err = dst_output(net, sk, skb);
151 static netdev_tx_t vrf_process_v6_outbound(struct sk_buff *skb,
152 struct net_device *dev)
154 const struct ipv6hdr *iph = ipv6_hdr(skb);
155 struct net *net = dev_net(skb->dev);
156 struct flowi6 fl6 = {
157 /* needed to match OIF rule */
158 .flowi6_oif = dev->ifindex,
159 .flowi6_iif = LOOPBACK_IFINDEX,
162 .flowlabel = ip6_flowinfo(iph),
163 .flowi6_mark = skb->mark,
164 .flowi6_proto = iph->nexthdr,
165 .flowi6_flags = FLOWI_FLAG_SKIP_NH_OIF,
167 int ret = NET_XMIT_DROP;
168 struct dst_entry *dst;
169 struct dst_entry *dst_null = &net->ipv6.ip6_null_entry->dst;
171 dst = ip6_route_output(net, NULL, &fl6);
177 /* if dst.dev is loopback or the VRF device again this is locally
178 * originated traffic destined to a local address. Short circuit
179 * to Rx path using our local dst
181 if (dst->dev == net->loopback_dev || dst->dev == dev) {
182 struct net_vrf *vrf = netdev_priv(dev);
183 struct rt6_info *rt6_local;
185 /* release looked up dst and use cached local dst */
190 rt6_local = rcu_dereference(vrf->rt6_local);
191 if (unlikely(!rt6_local)) {
196 /* Ordering issue: cached local dst is created on newlink
197 * before the IPv6 initialization. Using the local dst
198 * requires rt6i_idev to be set so make sure it is.
200 if (unlikely(!rt6_local->rt6i_idev)) {
201 rt6_local->rt6i_idev = in6_dev_get(dev);
202 if (!rt6_local->rt6i_idev) {
208 dst = &rt6_local->dst;
213 return vrf_local_xmit(skb, dev, &rt6_local->dst);
216 skb_dst_set(skb, dst);
218 /* strip the ethernet header added for pass through VRF device */
219 __skb_pull(skb, skb_network_offset(skb));
221 ret = vrf_ip6_local_out(net, skb->sk, skb);
222 if (unlikely(net_xmit_eval(ret)))
223 dev->stats.tx_errors++;
225 ret = NET_XMIT_SUCCESS;
229 vrf_tx_error(dev, skb);
230 return NET_XMIT_DROP;
233 static netdev_tx_t vrf_process_v6_outbound(struct sk_buff *skb,
234 struct net_device *dev)
236 vrf_tx_error(dev, skb);
237 return NET_XMIT_DROP;
241 /* based on ip_local_out; can't use it b/c the dst is switched pointing to us */
242 static int vrf_ip_local_out(struct net *net, struct sock *sk,
247 err = nf_hook(NFPROTO_IPV4, NF_INET_LOCAL_OUT, net, sk,
248 skb, NULL, skb_dst(skb)->dev, dst_output);
249 if (likely(err == 1))
250 err = dst_output(net, sk, skb);
255 static netdev_tx_t vrf_process_v4_outbound(struct sk_buff *skb,
256 struct net_device *vrf_dev)
258 struct iphdr *ip4h = ip_hdr(skb);
259 int ret = NET_XMIT_DROP;
260 struct flowi4 fl4 = {
261 /* needed to match OIF rule */
262 .flowi4_oif = vrf_dev->ifindex,
263 .flowi4_iif = LOOPBACK_IFINDEX,
264 .flowi4_tos = RT_TOS(ip4h->tos),
265 .flowi4_flags = FLOWI_FLAG_ANYSRC | FLOWI_FLAG_SKIP_NH_OIF,
266 .daddr = ip4h->daddr,
268 struct net *net = dev_net(vrf_dev);
271 rt = ip_route_output_flow(net, &fl4, NULL);
277 /* if dst.dev is loopback or the VRF device again this is locally
278 * originated traffic destined to a local address. Short circuit
279 * to Rx path using our local dst
281 if (rt->dst.dev == net->loopback_dev || rt->dst.dev == vrf_dev) {
282 struct net_vrf *vrf = netdev_priv(vrf_dev);
283 struct rtable *rth_local;
284 struct dst_entry *dst = NULL;
290 rth_local = rcu_dereference(vrf->rth_local);
291 if (likely(rth_local)) {
292 dst = &rth_local->dst;
301 return vrf_local_xmit(skb, vrf_dev, dst);
304 skb_dst_set(skb, &rt->dst);
306 /* strip the ethernet header added for pass through VRF device */
307 __skb_pull(skb, skb_network_offset(skb));
310 ip4h->saddr = inet_select_addr(skb_dst(skb)->dev, 0,
314 ret = vrf_ip_local_out(dev_net(skb_dst(skb)->dev), skb->sk, skb);
315 if (unlikely(net_xmit_eval(ret)))
316 vrf_dev->stats.tx_errors++;
318 ret = NET_XMIT_SUCCESS;
323 vrf_tx_error(vrf_dev, skb);
327 static netdev_tx_t is_ip_tx_frame(struct sk_buff *skb, struct net_device *dev)
329 switch (skb->protocol) {
330 case htons(ETH_P_IP):
331 return vrf_process_v4_outbound(skb, dev);
332 case htons(ETH_P_IPV6):
333 return vrf_process_v6_outbound(skb, dev);
335 vrf_tx_error(dev, skb);
336 return NET_XMIT_DROP;
340 static netdev_tx_t vrf_xmit(struct sk_buff *skb, struct net_device *dev)
342 netdev_tx_t ret = is_ip_tx_frame(skb, dev);
344 if (likely(ret == NET_XMIT_SUCCESS || ret == NET_XMIT_CN)) {
345 struct pcpu_dstats *dstats = this_cpu_ptr(dev->dstats);
347 u64_stats_update_begin(&dstats->syncp);
349 dstats->tx_bytes += skb->len;
350 u64_stats_update_end(&dstats->syncp);
352 this_cpu_inc(dev->dstats->tx_drps);
358 #if IS_ENABLED(CONFIG_IPV6)
359 /* modelled after ip6_finish_output2 */
360 static int vrf_finish_output6(struct net *net, struct sock *sk,
363 struct dst_entry *dst = skb_dst(skb);
364 struct net_device *dev = dst->dev;
365 struct neighbour *neigh;
366 struct in6_addr *nexthop;
369 skb->protocol = htons(ETH_P_IPV6);
373 nexthop = rt6_nexthop((struct rt6_info *)dst, &ipv6_hdr(skb)->daddr);
374 neigh = __ipv6_neigh_lookup_noref(dst->dev, nexthop);
375 if (unlikely(!neigh))
376 neigh = __neigh_create(&nd_tbl, nexthop, dst->dev, false);
377 if (!IS_ERR(neigh)) {
378 ret = dst_neigh_output(dst, neigh, skb);
379 rcu_read_unlock_bh();
382 rcu_read_unlock_bh();
384 IP6_INC_STATS(dev_net(dst->dev),
385 ip6_dst_idev(dst), IPSTATS_MIB_OUTNOROUTES);
390 /* modelled after ip6_output */
391 static int vrf_output6(struct net *net, struct sock *sk, struct sk_buff *skb)
393 return NF_HOOK_COND(NFPROTO_IPV6, NF_INET_POST_ROUTING,
394 net, sk, skb, NULL, skb_dst(skb)->dev,
396 !(IP6CB(skb)->flags & IP6SKB_REROUTED));
399 /* set dst on skb to send packet to us via dev_xmit path. Allows
400 * packet to go through device based features such as qdisc, netfilter
401 * hooks and packet sockets with skb->dev set to vrf device.
403 static struct sk_buff *vrf_ip6_out(struct net_device *vrf_dev,
407 struct net_vrf *vrf = netdev_priv(vrf_dev);
408 struct dst_entry *dst = NULL;
409 struct rt6_info *rt6;
411 /* don't divert link scope packets */
412 if (rt6_need_strict(&ipv6_hdr(skb)->daddr))
417 rt6 = rcu_dereference(vrf->rt6);
425 if (unlikely(!dst)) {
426 vrf_tx_error(vrf_dev, skb);
431 skb_dst_set(skb, dst);
437 static void vrf_rt6_release(struct net_device *dev, struct net_vrf *vrf)
439 struct rt6_info *rt6 = rtnl_dereference(vrf->rt6);
440 struct rt6_info *rt6_local = rtnl_dereference(vrf->rt6_local);
441 struct net *net = dev_net(dev);
442 struct dst_entry *dst;
444 RCU_INIT_POINTER(vrf->rt6, NULL);
445 RCU_INIT_POINTER(vrf->rt6_local, NULL);
448 /* move dev in dst's to loopback so this VRF device can be deleted
449 * - based on dst_ifdown
454 dst->dev = net->loopback_dev;
460 if (rt6_local->rt6i_idev)
461 in6_dev_put(rt6_local->rt6i_idev);
463 dst = &rt6_local->dst;
465 dst->dev = net->loopback_dev;
471 static int vrf_rt6_create(struct net_device *dev)
473 int flags = DST_HOST | DST_NOPOLICY | DST_NOXFRM | DST_NOCACHE;
474 struct net_vrf *vrf = netdev_priv(dev);
475 struct net *net = dev_net(dev);
476 struct fib6_table *rt6i_table;
477 struct rt6_info *rt6, *rt6_local;
480 /* IPv6 can be CONFIG enabled and then disabled runtime */
481 if (!ipv6_mod_enabled())
484 rt6i_table = fib6_new_table(net, vrf->tb_id);
488 /* create a dst for routing packets out a VRF device */
489 rt6 = ip6_dst_alloc(net, dev, flags);
495 rt6->rt6i_table = rt6i_table;
496 rt6->dst.output = vrf_output6;
498 /* create a dst for local routing - packets sent locally
499 * to local address via the VRF device as a loopback
501 rt6_local = ip6_dst_alloc(net, dev, flags);
503 dst_release(&rt6->dst);
507 dst_hold(&rt6_local->dst);
509 rt6_local->rt6i_idev = in6_dev_get(dev);
510 rt6_local->rt6i_flags = RTF_UP | RTF_NONEXTHOP | RTF_LOCAL;
511 rt6_local->rt6i_table = rt6i_table;
512 rt6_local->dst.input = ip6_input;
514 rcu_assign_pointer(vrf->rt6, rt6);
515 rcu_assign_pointer(vrf->rt6_local, rt6_local);
522 static struct sk_buff *vrf_ip6_out(struct net_device *vrf_dev,
529 static void vrf_rt6_release(struct net_device *dev, struct net_vrf *vrf)
533 static int vrf_rt6_create(struct net_device *dev)
539 /* modelled after ip_finish_output2 */
540 static int vrf_finish_output(struct net *net, struct sock *sk, struct sk_buff *skb)
542 struct dst_entry *dst = skb_dst(skb);
543 struct rtable *rt = (struct rtable *)dst;
544 struct net_device *dev = dst->dev;
545 unsigned int hh_len = LL_RESERVED_SPACE(dev);
546 struct neighbour *neigh;
550 /* Be paranoid, rather than too clever. */
551 if (unlikely(skb_headroom(skb) < hh_len && dev->header_ops)) {
552 struct sk_buff *skb2;
554 skb2 = skb_realloc_headroom(skb, LL_RESERVED_SPACE(dev));
560 skb_set_owner_w(skb2, skb->sk);
568 nexthop = (__force u32)rt_nexthop(rt, ip_hdr(skb)->daddr);
569 neigh = __ipv4_neigh_lookup_noref(dev, nexthop);
570 if (unlikely(!neigh))
571 neigh = __neigh_create(&arp_tbl, &nexthop, dev, false);
573 ret = dst_neigh_output(dst, neigh, skb);
575 rcu_read_unlock_bh();
577 if (unlikely(ret < 0))
578 vrf_tx_error(skb->dev, skb);
582 static int vrf_output(struct net *net, struct sock *sk, struct sk_buff *skb)
584 struct net_device *dev = skb_dst(skb)->dev;
586 IP_UPD_PO_STATS(net, IPSTATS_MIB_OUT, skb->len);
589 skb->protocol = htons(ETH_P_IP);
591 return NF_HOOK_COND(NFPROTO_IPV4, NF_INET_POST_ROUTING,
592 net, sk, skb, NULL, dev,
594 !(IPCB(skb)->flags & IPSKB_REROUTED));
597 /* set dst on skb to send packet to us via dev_xmit path. Allows
598 * packet to go through device based features such as qdisc, netfilter
599 * hooks and packet sockets with skb->dev set to vrf device.
601 static struct sk_buff *vrf_ip_out(struct net_device *vrf_dev,
605 struct net_vrf *vrf = netdev_priv(vrf_dev);
606 struct dst_entry *dst = NULL;
609 /* don't divert multicast */
610 if (ipv4_is_multicast(ip_hdr(skb)->daddr))
615 rth = rcu_dereference(vrf->rth);
623 if (unlikely(!dst)) {
624 vrf_tx_error(vrf_dev, skb);
629 skb_dst_set(skb, dst);
634 /* called with rcu lock held */
635 static struct sk_buff *vrf_l3_out(struct net_device *vrf_dev,
642 return vrf_ip_out(vrf_dev, sk, skb);
644 return vrf_ip6_out(vrf_dev, sk, skb);
651 static void vrf_rtable_release(struct net_device *dev, struct net_vrf *vrf)
653 struct rtable *rth = rtnl_dereference(vrf->rth);
654 struct rtable *rth_local = rtnl_dereference(vrf->rth_local);
655 struct net *net = dev_net(dev);
656 struct dst_entry *dst;
658 RCU_INIT_POINTER(vrf->rth, NULL);
659 RCU_INIT_POINTER(vrf->rth_local, NULL);
662 /* move dev in dst's to loopback so this VRF device can be deleted
663 * - based on dst_ifdown
668 dst->dev = net->loopback_dev;
674 dst = &rth_local->dst;
676 dst->dev = net->loopback_dev;
682 static int vrf_rtable_create(struct net_device *dev)
684 struct net_vrf *vrf = netdev_priv(dev);
685 struct rtable *rth, *rth_local;
687 if (!fib_new_table(dev_net(dev), vrf->tb_id))
690 /* create a dst for routing packets out through a VRF device */
691 rth = rt_dst_alloc(dev, 0, RTN_UNICAST, 1, 1, 0);
695 /* create a dst for local ingress routing - packets sent locally
696 * to local address via the VRF device as a loopback
698 rth_local = rt_dst_alloc(dev, RTCF_LOCAL, RTN_LOCAL, 1, 1, 0);
700 dst_release(&rth->dst);
704 rth->dst.output = vrf_output;
705 rth->rt_table_id = vrf->tb_id;
707 rth_local->rt_table_id = vrf->tb_id;
709 rcu_assign_pointer(vrf->rth, rth);
710 rcu_assign_pointer(vrf->rth_local, rth_local);
715 /**************************** device handling ********************/
717 /* cycle interface to flush neighbor cache and move routes across tables */
718 static void cycle_netdev(struct net_device *dev)
720 unsigned int flags = dev->flags;
723 if (!netif_running(dev))
726 ret = dev_change_flags(dev, flags & ~IFF_UP);
728 ret = dev_change_flags(dev, flags);
732 "Failed to cycle device %s; route tables might be wrong!\n",
737 static int do_vrf_add_slave(struct net_device *dev, struct net_device *port_dev)
741 ret = netdev_master_upper_dev_link(port_dev, dev, NULL, NULL);
745 port_dev->priv_flags |= IFF_L3MDEV_SLAVE;
746 cycle_netdev(port_dev);
751 static int vrf_add_slave(struct net_device *dev, struct net_device *port_dev)
753 if (netif_is_l3_master(port_dev) || netif_is_l3_slave(port_dev))
756 return do_vrf_add_slave(dev, port_dev);
759 /* inverse of do_vrf_add_slave */
760 static int do_vrf_del_slave(struct net_device *dev, struct net_device *port_dev)
762 netdev_upper_dev_unlink(port_dev, dev);
763 port_dev->priv_flags &= ~IFF_L3MDEV_SLAVE;
765 cycle_netdev(port_dev);
770 static int vrf_del_slave(struct net_device *dev, struct net_device *port_dev)
772 return do_vrf_del_slave(dev, port_dev);
775 static void vrf_dev_uninit(struct net_device *dev)
777 struct net_vrf *vrf = netdev_priv(dev);
778 struct net_device *port_dev;
779 struct list_head *iter;
781 vrf_rtable_release(dev, vrf);
782 vrf_rt6_release(dev, vrf);
784 netdev_for_each_lower_dev(dev, port_dev, iter)
785 vrf_del_slave(dev, port_dev);
787 free_percpu(dev->dstats);
791 static int vrf_dev_init(struct net_device *dev)
793 struct net_vrf *vrf = netdev_priv(dev);
795 dev->dstats = netdev_alloc_pcpu_stats(struct pcpu_dstats);
799 /* create the default dst which points back to us */
800 if (vrf_rtable_create(dev) != 0)
803 if (vrf_rt6_create(dev) != 0)
806 dev->flags = IFF_MASTER | IFF_NOARP;
808 /* MTU is irrelevant for VRF device; set to 64k similar to lo */
809 dev->mtu = 64 * 1024;
811 /* similarly, oper state is irrelevant; set to up to avoid confusion */
812 dev->operstate = IF_OPER_UP;
813 netdev_lockdep_set_classes(dev);
817 vrf_rtable_release(dev, vrf);
819 free_percpu(dev->dstats);
825 static const struct net_device_ops vrf_netdev_ops = {
826 .ndo_init = vrf_dev_init,
827 .ndo_uninit = vrf_dev_uninit,
828 .ndo_start_xmit = vrf_xmit,
829 .ndo_get_stats64 = vrf_get_stats64,
830 .ndo_add_slave = vrf_add_slave,
831 .ndo_del_slave = vrf_del_slave,
834 static u32 vrf_fib_table(const struct net_device *dev)
836 struct net_vrf *vrf = netdev_priv(dev);
841 static int vrf_rcv_finish(struct net *net, struct sock *sk, struct sk_buff *skb)
846 static struct sk_buff *vrf_rcv_nfhook(u8 pf, unsigned int hook,
848 struct net_device *dev)
850 struct net *net = dev_net(dev);
854 if (NF_HOOK(pf, hook, net, NULL, skb, dev, NULL, vrf_rcv_finish) < 0)
855 skb = NULL; /* kfree_skb(skb) handled by nf code */
860 #if IS_ENABLED(CONFIG_IPV6)
861 /* neighbor handling is done with actual device; do not want
862 * to flip skb->dev for those ndisc packets. This really fails
863 * for multiple next protocols (e.g., NEXTHDR_HOP). But it is
866 static bool ipv6_ndisc_frame(const struct sk_buff *skb)
868 const struct ipv6hdr *iph = ipv6_hdr(skb);
871 if (iph->nexthdr == NEXTHDR_ICMP) {
872 const struct icmp6hdr *icmph;
873 struct icmp6hdr _icmph;
875 icmph = skb_header_pointer(skb, sizeof(*iph),
876 sizeof(_icmph), &_icmph);
880 switch (icmph->icmp6_type) {
881 case NDISC_ROUTER_SOLICITATION:
882 case NDISC_ROUTER_ADVERTISEMENT:
883 case NDISC_NEIGHBOUR_SOLICITATION:
884 case NDISC_NEIGHBOUR_ADVERTISEMENT:
895 static struct rt6_info *vrf_ip6_route_lookup(struct net *net,
896 const struct net_device *dev,
901 struct net_vrf *vrf = netdev_priv(dev);
902 struct fib6_table *table = NULL;
903 struct rt6_info *rt6;
907 /* fib6_table does not have a refcnt and can not be freed */
908 rt6 = rcu_dereference(vrf->rt6);
910 table = rt6->rt6i_table;
917 return ip6_pol_route(net, table, ifindex, fl6, flags);
920 static void vrf_ip6_input_dst(struct sk_buff *skb, struct net_device *vrf_dev,
923 const struct ipv6hdr *iph = ipv6_hdr(skb);
924 struct flowi6 fl6 = {
927 .flowlabel = ip6_flowinfo(iph),
928 .flowi6_mark = skb->mark,
929 .flowi6_proto = iph->nexthdr,
930 .flowi6_iif = ifindex,
932 struct net *net = dev_net(vrf_dev);
933 struct rt6_info *rt6;
935 rt6 = vrf_ip6_route_lookup(net, vrf_dev, &fl6, ifindex,
936 RT6_LOOKUP_F_HAS_SADDR | RT6_LOOKUP_F_IFACE);
940 if (unlikely(&rt6->dst == &net->ipv6.ip6_null_entry->dst))
943 skb_dst_set(skb, &rt6->dst);
946 static struct sk_buff *vrf_ip6_rcv(struct net_device *vrf_dev,
949 int orig_iif = skb->skb_iif;
952 /* loopback traffic; do not push through packet taps again.
953 * Reset pkt_type for upper layers to process skb
955 if (skb->pkt_type == PACKET_LOOPBACK) {
957 skb->skb_iif = vrf_dev->ifindex;
958 IP6CB(skb)->flags |= IP6SKB_L3SLAVE;
959 skb->pkt_type = PACKET_HOST;
963 /* if packet is NDISC or addressed to multicast or link-local
964 * then keep the ingress interface
966 need_strict = rt6_need_strict(&ipv6_hdr(skb)->daddr);
967 if (!ipv6_ndisc_frame(skb) && !need_strict) {
969 skb->skb_iif = vrf_dev->ifindex;
971 skb_push(skb, skb->mac_len);
972 dev_queue_xmit_nit(skb, vrf_dev);
973 skb_pull(skb, skb->mac_len);
975 IP6CB(skb)->flags |= IP6SKB_L3SLAVE;
979 vrf_ip6_input_dst(skb, vrf_dev, orig_iif);
981 skb = vrf_rcv_nfhook(NFPROTO_IPV6, NF_INET_PRE_ROUTING, skb, vrf_dev);
987 static struct sk_buff *vrf_ip6_rcv(struct net_device *vrf_dev,
994 static struct sk_buff *vrf_ip_rcv(struct net_device *vrf_dev,
998 skb->skb_iif = vrf_dev->ifindex;
999 IPCB(skb)->flags |= IPSKB_L3SLAVE;
1001 if (ipv4_is_multicast(ip_hdr(skb)->daddr))
1004 /* loopback traffic; do not push through packet taps again.
1005 * Reset pkt_type for upper layers to process skb
1007 if (skb->pkt_type == PACKET_LOOPBACK) {
1008 skb->pkt_type = PACKET_HOST;
1012 skb_push(skb, skb->mac_len);
1013 dev_queue_xmit_nit(skb, vrf_dev);
1014 skb_pull(skb, skb->mac_len);
1016 skb = vrf_rcv_nfhook(NFPROTO_IPV4, NF_INET_PRE_ROUTING, skb, vrf_dev);
1021 /* called with rcu lock held */
1022 static struct sk_buff *vrf_l3_rcv(struct net_device *vrf_dev,
1023 struct sk_buff *skb,
1028 return vrf_ip_rcv(vrf_dev, skb);
1030 return vrf_ip6_rcv(vrf_dev, skb);
1036 #if IS_ENABLED(CONFIG_IPV6)
1037 /* send to link-local or multicast address via interface enslaved to
1038 * VRF device. Force lookup to VRF table without changing flow struct
1040 static struct dst_entry *vrf_link_scope_lookup(const struct net_device *dev,
1043 struct net *net = dev_net(dev);
1044 int flags = RT6_LOOKUP_F_IFACE;
1045 struct dst_entry *dst = NULL;
1046 struct rt6_info *rt;
1048 /* VRF device does not have a link-local address and
1049 * sending packets to link-local or mcast addresses over
1050 * a VRF device does not make sense
1052 if (fl6->flowi6_oif == dev->ifindex) {
1053 dst = &net->ipv6.ip6_null_entry->dst;
1058 if (!ipv6_addr_any(&fl6->saddr))
1059 flags |= RT6_LOOKUP_F_HAS_SADDR;
1061 rt = vrf_ip6_route_lookup(net, dev, fl6, fl6->flowi6_oif, flags);
1069 static const struct l3mdev_ops vrf_l3mdev_ops = {
1070 .l3mdev_fib_table = vrf_fib_table,
1071 .l3mdev_l3_rcv = vrf_l3_rcv,
1072 .l3mdev_l3_out = vrf_l3_out,
1073 #if IS_ENABLED(CONFIG_IPV6)
1074 .l3mdev_link_scope_lookup = vrf_link_scope_lookup,
1078 static void vrf_get_drvinfo(struct net_device *dev,
1079 struct ethtool_drvinfo *info)
1081 strlcpy(info->driver, DRV_NAME, sizeof(info->driver));
1082 strlcpy(info->version, DRV_VERSION, sizeof(info->version));
1085 static const struct ethtool_ops vrf_ethtool_ops = {
1086 .get_drvinfo = vrf_get_drvinfo,
1089 static inline size_t vrf_fib_rule_nl_size(void)
1093 sz = NLMSG_ALIGN(sizeof(struct fib_rule_hdr));
1094 sz += nla_total_size(sizeof(u8)); /* FRA_L3MDEV */
1095 sz += nla_total_size(sizeof(u32)); /* FRA_PRIORITY */
1100 static int vrf_fib_rule(const struct net_device *dev, __u8 family, bool add_it)
1102 struct fib_rule_hdr *frh;
1103 struct nlmsghdr *nlh;
1104 struct sk_buff *skb;
1107 if (family == AF_INET6 && !ipv6_mod_enabled())
1110 skb = nlmsg_new(vrf_fib_rule_nl_size(), GFP_KERNEL);
1114 nlh = nlmsg_put(skb, 0, 0, 0, sizeof(*frh), 0);
1116 goto nla_put_failure;
1118 /* rule only needs to appear once */
1119 nlh->nlmsg_flags &= NLM_F_EXCL;
1121 frh = nlmsg_data(nlh);
1122 memset(frh, 0, sizeof(*frh));
1123 frh->family = family;
1124 frh->action = FR_ACT_TO_TBL;
1126 if (nla_put_u32(skb, FRA_L3MDEV, 1))
1127 goto nla_put_failure;
1129 if (nla_put_u32(skb, FRA_PRIORITY, FIB_RULE_PREF))
1130 goto nla_put_failure;
1132 nlmsg_end(skb, nlh);
1134 /* fib_nl_{new,del}rule handling looks for net from skb->sk */
1135 skb->sk = dev_net(dev)->rtnl;
1137 err = fib_nl_newrule(skb, nlh);
1141 err = fib_nl_delrule(skb, nlh);
1155 static int vrf_add_fib_rules(const struct net_device *dev)
1159 err = vrf_fib_rule(dev, AF_INET, true);
1163 err = vrf_fib_rule(dev, AF_INET6, true);
1167 #if IS_ENABLED(CONFIG_IP_MROUTE_MULTIPLE_TABLES)
1168 err = vrf_fib_rule(dev, RTNL_FAMILY_IPMR, true);
1175 #if IS_ENABLED(CONFIG_IP_MROUTE_MULTIPLE_TABLES)
1177 vrf_fib_rule(dev, AF_INET6, false);
1181 vrf_fib_rule(dev, AF_INET, false);
1184 netdev_err(dev, "Failed to add FIB rules.\n");
1188 static void vrf_setup(struct net_device *dev)
1192 /* Initialize the device structure. */
1193 dev->netdev_ops = &vrf_netdev_ops;
1194 dev->l3mdev_ops = &vrf_l3mdev_ops;
1195 dev->ethtool_ops = &vrf_ethtool_ops;
1196 dev->destructor = free_netdev;
1198 /* Fill in device structure with ethernet-generic values. */
1199 eth_hw_addr_random(dev);
1201 /* don't acquire vrf device's netif_tx_lock when transmitting */
1202 dev->features |= NETIF_F_LLTX;
1204 /* don't allow vrf devices to change network namespaces. */
1205 dev->features |= NETIF_F_NETNS_LOCAL;
1207 /* does not make sense for a VLAN to be added to a vrf device */
1208 dev->features |= NETIF_F_VLAN_CHALLENGED;
1210 /* enable offload features */
1211 dev->features |= NETIF_F_GSO_SOFTWARE;
1212 dev->features |= NETIF_F_RXCSUM | NETIF_F_HW_CSUM;
1213 dev->features |= NETIF_F_SG | NETIF_F_FRAGLIST | NETIF_F_HIGHDMA;
1215 dev->hw_features = dev->features;
1216 dev->hw_enc_features = dev->features;
1218 /* default to no qdisc; user can add if desired */
1219 dev->priv_flags |= IFF_NO_QUEUE;
1222 static int vrf_validate(struct nlattr *tb[], struct nlattr *data[])
1224 if (tb[IFLA_ADDRESS]) {
1225 if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
1227 if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
1228 return -EADDRNOTAVAIL;
1233 static void vrf_dellink(struct net_device *dev, struct list_head *head)
1235 unregister_netdevice_queue(dev, head);
1238 static int vrf_newlink(struct net *src_net, struct net_device *dev,
1239 struct nlattr *tb[], struct nlattr *data[])
1241 struct net_vrf *vrf = netdev_priv(dev);
1244 if (!data || !data[IFLA_VRF_TABLE])
1247 vrf->tb_id = nla_get_u32(data[IFLA_VRF_TABLE]);
1249 dev->priv_flags |= IFF_L3MDEV_MASTER;
1251 err = register_netdevice(dev);
1255 if (add_fib_rules) {
1256 err = vrf_add_fib_rules(dev);
1258 unregister_netdevice(dev);
1261 add_fib_rules = false;
1268 static size_t vrf_nl_getsize(const struct net_device *dev)
1270 return nla_total_size(sizeof(u32)); /* IFLA_VRF_TABLE */
1273 static int vrf_fillinfo(struct sk_buff *skb,
1274 const struct net_device *dev)
1276 struct net_vrf *vrf = netdev_priv(dev);
1278 return nla_put_u32(skb, IFLA_VRF_TABLE, vrf->tb_id);
1281 static size_t vrf_get_slave_size(const struct net_device *bond_dev,
1282 const struct net_device *slave_dev)
1284 return nla_total_size(sizeof(u32)); /* IFLA_VRF_PORT_TABLE */
1287 static int vrf_fill_slave_info(struct sk_buff *skb,
1288 const struct net_device *vrf_dev,
1289 const struct net_device *slave_dev)
1291 struct net_vrf *vrf = netdev_priv(vrf_dev);
1293 if (nla_put_u32(skb, IFLA_VRF_PORT_TABLE, vrf->tb_id))
1299 static const struct nla_policy vrf_nl_policy[IFLA_VRF_MAX + 1] = {
1300 [IFLA_VRF_TABLE] = { .type = NLA_U32 },
1303 static struct rtnl_link_ops vrf_link_ops __read_mostly = {
1305 .priv_size = sizeof(struct net_vrf),
1307 .get_size = vrf_nl_getsize,
1308 .policy = vrf_nl_policy,
1309 .validate = vrf_validate,
1310 .fill_info = vrf_fillinfo,
1312 .get_slave_size = vrf_get_slave_size,
1313 .fill_slave_info = vrf_fill_slave_info,
1315 .newlink = vrf_newlink,
1316 .dellink = vrf_dellink,
1318 .maxtype = IFLA_VRF_MAX,
1321 static int vrf_device_event(struct notifier_block *unused,
1322 unsigned long event, void *ptr)
1324 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
1326 /* only care about unregister events to drop slave references */
1327 if (event == NETDEV_UNREGISTER) {
1328 struct net_device *vrf_dev;
1330 if (!netif_is_l3_slave(dev))
1333 vrf_dev = netdev_master_upper_dev_get(dev);
1334 vrf_del_slave(vrf_dev, dev);
1340 static struct notifier_block vrf_notifier_block __read_mostly = {
1341 .notifier_call = vrf_device_event,
1344 static int __init vrf_init_module(void)
1348 register_netdevice_notifier(&vrf_notifier_block);
1350 rc = rtnl_link_register(&vrf_link_ops);
1357 unregister_netdevice_notifier(&vrf_notifier_block);
1361 module_init(vrf_init_module);
1362 MODULE_AUTHOR("Shrijeet Mukherjee, David Ahern");
1363 MODULE_DESCRIPTION("Device driver to instantiate VRF domains");
1364 MODULE_LICENSE("GPL");
1365 MODULE_ALIAS_RTNL_LINK(DRV_NAME);
1366 MODULE_VERSION(DRV_VERSION);