1 // SPDX-License-Identifier: GPL-2.0
3 * XFRM virtual interface
5 * Copyright (C) 2018 secunet Security Networks AG
11 #include <linux/module.h>
12 #include <linux/capability.h>
13 #include <linux/errno.h>
14 #include <linux/types.h>
15 #include <linux/sockios.h>
16 #include <linux/icmp.h>
20 #include <linux/net.h>
21 #include <linux/in6.h>
22 #include <linux/netdevice.h>
23 #include <linux/if_link.h>
24 #include <linux/if_arp.h>
25 #include <linux/icmpv6.h>
26 #include <linux/init.h>
27 #include <linux/route.h>
28 #include <linux/rtnetlink.h>
29 #include <linux/netfilter_ipv6.h>
30 #include <linux/slab.h>
31 #include <linux/hash.h>
33 #include <linux/uaccess.h>
34 #include <linux/atomic.h>
39 #include <net/ip6_route.h>
40 #include <net/addrconf.h>
42 #include <net/net_namespace.h>
43 #include <net/netns/generic.h>
44 #include <linux/etherdevice.h>
46 static int xfrmi_dev_init(struct net_device *dev);
47 static void xfrmi_dev_setup(struct net_device *dev);
48 static struct rtnl_link_ops xfrmi_link_ops __read_mostly;
49 static unsigned int xfrmi_net_id __read_mostly;
52 /* lists for storing interfaces in use */
53 struct xfrm_if __rcu *xfrmi[1];
56 #define for_each_xfrmi_rcu(start, xi) \
57 for (xi = rcu_dereference(start); xi; xi = rcu_dereference(xi->next))
59 static struct xfrm_if *xfrmi_lookup(struct net *net, struct xfrm_state *x)
61 struct xfrmi_net *xfrmn = net_generic(net, xfrmi_net_id);
64 for_each_xfrmi_rcu(xfrmn->xfrmi[0], xi) {
65 if (x->if_id == xi->p.if_id &&
66 (xi->dev->flags & IFF_UP))
73 static struct xfrm_if *xfrmi_decode_session(struct sk_buff *skb,
74 unsigned short family)
76 struct xfrmi_net *xfrmn;
80 if (!secpath_exists(skb) || !skb->dev)
85 ifindex = inet6_sdif(skb);
88 ifindex = inet_sdif(skb);
92 ifindex = skb->dev->ifindex;
94 xfrmn = net_generic(xs_net(xfrm_input_state(skb)), xfrmi_net_id);
96 for_each_xfrmi_rcu(xfrmn->xfrmi[0], xi) {
97 if (ifindex == xi->dev->ifindex &&
98 (xi->dev->flags & IFF_UP))
105 static void xfrmi_link(struct xfrmi_net *xfrmn, struct xfrm_if *xi)
107 struct xfrm_if __rcu **xip = &xfrmn->xfrmi[0];
109 rcu_assign_pointer(xi->next , rtnl_dereference(*xip));
110 rcu_assign_pointer(*xip, xi);
113 static void xfrmi_unlink(struct xfrmi_net *xfrmn, struct xfrm_if *xi)
115 struct xfrm_if __rcu **xip;
116 struct xfrm_if *iter;
118 for (xip = &xfrmn->xfrmi[0];
119 (iter = rtnl_dereference(*xip)) != NULL;
122 rcu_assign_pointer(*xip, xi->next);
128 static void xfrmi_dev_free(struct net_device *dev)
130 struct xfrm_if *xi = netdev_priv(dev);
132 gro_cells_destroy(&xi->gro_cells);
133 free_percpu(dev->tstats);
136 static int xfrmi_create(struct net_device *dev)
138 struct xfrm_if *xi = netdev_priv(dev);
139 struct net *net = dev_net(dev);
140 struct xfrmi_net *xfrmn = net_generic(net, xfrmi_net_id);
143 dev->rtnl_link_ops = &xfrmi_link_ops;
144 err = register_netdevice(dev);
149 xfrmi_link(xfrmn, xi);
157 static struct xfrm_if *xfrmi_locate(struct net *net, struct xfrm_if_parms *p)
159 struct xfrm_if __rcu **xip;
161 struct xfrmi_net *xfrmn = net_generic(net, xfrmi_net_id);
163 for (xip = &xfrmn->xfrmi[0];
164 (xi = rtnl_dereference(*xip)) != NULL;
166 if (xi->p.if_id == p->if_id)
172 static void xfrmi_dev_uninit(struct net_device *dev)
174 struct xfrm_if *xi = netdev_priv(dev);
175 struct xfrmi_net *xfrmn = net_generic(xi->net, xfrmi_net_id);
177 xfrmi_unlink(xfrmn, xi);
181 static void xfrmi_scrub_packet(struct sk_buff *skb, bool xnet)
184 skb->pkt_type = PACKET_HOST;
200 static int xfrmi_rcv_cb(struct sk_buff *skb, int err)
202 const struct xfrm_mode *inner_mode;
203 struct pcpu_sw_netstats *tstats;
204 struct net_device *dev;
205 struct xfrm_state *x;
209 if (err && !secpath_exists(skb))
212 x = xfrm_input_state(skb);
214 xi = xfrmi_lookup(xs_net(x), x);
222 dev->stats.rx_errors++;
223 dev->stats.rx_dropped++;
228 xnet = !net_eq(xi->net, dev_net(skb->dev));
231 inner_mode = &x->inner_mode;
233 if (x->sel.family == AF_UNSPEC) {
234 inner_mode = xfrm_ip2inner_mode(x, XFRM_MODE_SKB_CB(skb)->protocol);
235 if (inner_mode == NULL) {
236 XFRM_INC_STATS(dev_net(skb->dev),
237 LINUX_MIB_XFRMINSTATEMODEERROR);
242 if (!xfrm_policy_check(NULL, XFRM_POLICY_IN, skb,
247 xfrmi_scrub_packet(skb, xnet);
249 tstats = this_cpu_ptr(dev->tstats);
251 u64_stats_update_begin(&tstats->syncp);
252 tstats->rx_packets++;
253 tstats->rx_bytes += skb->len;
254 u64_stats_update_end(&tstats->syncp);
260 xfrmi_xmit2(struct sk_buff *skb, struct net_device *dev, struct flowi *fl)
262 struct xfrm_if *xi = netdev_priv(dev);
263 struct net_device_stats *stats = &xi->dev->stats;
264 struct dst_entry *dst = skb_dst(skb);
265 unsigned int length = skb->len;
266 struct net_device *tdev;
267 struct xfrm_state *x;
272 dst = xfrm_lookup_with_ifid(xi->net, dst, fl, NULL, 0, xi->p.if_id);
276 goto tx_err_link_failure;
281 goto tx_err_link_failure;
283 if (x->if_id != xi->p.if_id)
284 goto tx_err_link_failure;
290 net_warn_ratelimited("%s: Local routing loop detected!\n",
292 goto tx_err_dst_release;
296 if (!skb->ignore_df && skb->len > mtu) {
297 skb_dst_update_pmtu(skb, mtu);
299 if (skb->protocol == htons(ETH_P_IPV6)) {
300 if (mtu < IPV6_MIN_MTU)
303 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
305 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
313 xfrmi_scrub_packet(skb, !net_eq(xi->net, dev_net(dev)));
314 skb_dst_set(skb, dst);
317 err = dst_output(xi->net, skb->sk, skb);
318 if (net_xmit_eval(err) == 0) {
319 struct pcpu_sw_netstats *tstats = this_cpu_ptr(dev->tstats);
321 u64_stats_update_begin(&tstats->syncp);
322 tstats->tx_bytes += length;
323 tstats->tx_packets++;
324 u64_stats_update_end(&tstats->syncp);
327 stats->tx_aborted_errors++;
332 stats->tx_carrier_errors++;
333 dst_link_failure(skb);
339 static netdev_tx_t xfrmi_xmit(struct sk_buff *skb, struct net_device *dev)
341 struct xfrm_if *xi = netdev_priv(dev);
342 struct net_device_stats *stats = &xi->dev->stats;
343 struct dst_entry *dst = skb_dst(skb);
347 memset(&fl, 0, sizeof(fl));
349 switch (skb->protocol) {
350 case htons(ETH_P_IPV6):
351 xfrm_decode_session(skb, &fl, AF_INET6);
352 memset(IP6CB(skb), 0, sizeof(*IP6CB(skb)));
354 fl.u.ip6.flowi6_oif = dev->ifindex;
355 fl.u.ip6.flowi6_flags |= FLOWI_FLAG_ANYSRC;
356 dst = ip6_route_output(dev_net(dev), NULL, &fl.u.ip6);
359 stats->tx_carrier_errors++;
362 skb_dst_set(skb, dst);
365 case htons(ETH_P_IP):
366 xfrm_decode_session(skb, &fl, AF_INET);
367 memset(IPCB(skb), 0, sizeof(*IPCB(skb)));
371 fl.u.ip4.flowi4_oif = dev->ifindex;
372 fl.u.ip4.flowi4_flags |= FLOWI_FLAG_ANYSRC;
373 rt = __ip_route_output_key(dev_net(dev), &fl.u.ip4);
375 stats->tx_carrier_errors++;
378 skb_dst_set(skb, &rt->dst);
385 fl.flowi_oif = xi->p.link;
387 ret = xfrmi_xmit2(skb, dev, &fl);
400 static int xfrmi4_err(struct sk_buff *skb, u32 info)
402 const struct iphdr *iph = (const struct iphdr *)skb->data;
403 struct net *net = dev_net(skb->dev);
404 int protocol = iph->protocol;
405 struct ip_comp_hdr *ipch;
406 struct ip_esp_hdr *esph;
407 struct ip_auth_hdr *ah ;
408 struct xfrm_state *x;
414 esph = (struct ip_esp_hdr *)(skb->data+(iph->ihl<<2));
418 ah = (struct ip_auth_hdr *)(skb->data+(iph->ihl<<2));
422 ipch = (struct ip_comp_hdr *)(skb->data+(iph->ihl<<2));
423 spi = htonl(ntohs(ipch->cpi));
429 switch (icmp_hdr(skb)->type) {
430 case ICMP_DEST_UNREACH:
431 if (icmp_hdr(skb)->code != ICMP_FRAG_NEEDED)
439 x = xfrm_state_lookup(net, skb->mark, (const xfrm_address_t *)&iph->daddr,
440 spi, protocol, AF_INET);
444 xi = xfrmi_lookup(net, x);
450 if (icmp_hdr(skb)->type == ICMP_DEST_UNREACH)
451 ipv4_update_pmtu(skb, net, info, 0, protocol);
453 ipv4_redirect(skb, net, 0, protocol);
459 static int xfrmi6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
460 u8 type, u8 code, int offset, __be32 info)
462 const struct ipv6hdr *iph = (const struct ipv6hdr *)skb->data;
463 struct net *net = dev_net(skb->dev);
464 int protocol = iph->nexthdr;
465 struct ip_comp_hdr *ipch;
466 struct ip_esp_hdr *esph;
467 struct ip_auth_hdr *ah;
468 struct xfrm_state *x;
474 esph = (struct ip_esp_hdr *)(skb->data + offset);
478 ah = (struct ip_auth_hdr *)(skb->data + offset);
482 ipch = (struct ip_comp_hdr *)(skb->data + offset);
483 spi = htonl(ntohs(ipch->cpi));
489 if (type != ICMPV6_PKT_TOOBIG &&
490 type != NDISC_REDIRECT)
493 x = xfrm_state_lookup(net, skb->mark, (const xfrm_address_t *)&iph->daddr,
494 spi, protocol, AF_INET6);
498 xi = xfrmi_lookup(net, x);
504 if (type == NDISC_REDIRECT)
505 ip6_redirect(skb, net, skb->dev->ifindex, 0,
506 sock_net_uid(net, NULL));
508 ip6_update_pmtu(skb, net, info, 0, 0, sock_net_uid(net, NULL));
514 static int xfrmi_change(struct xfrm_if *xi, const struct xfrm_if_parms *p)
516 if (xi->p.link != p->link)
519 xi->p.if_id = p->if_id;
524 static int xfrmi_update(struct xfrm_if *xi, struct xfrm_if_parms *p)
526 struct net *net = xi->net;
527 struct xfrmi_net *xfrmn = net_generic(net, xfrmi_net_id);
530 xfrmi_unlink(xfrmn, xi);
532 err = xfrmi_change(xi, p);
533 xfrmi_link(xfrmn, xi);
534 netdev_state_change(xi->dev);
538 static void xfrmi_get_stats64(struct net_device *dev,
539 struct rtnl_link_stats64 *s)
543 for_each_possible_cpu(cpu) {
544 struct pcpu_sw_netstats *stats;
545 struct pcpu_sw_netstats tmp;
548 stats = per_cpu_ptr(dev->tstats, cpu);
550 start = u64_stats_fetch_begin_irq(&stats->syncp);
551 tmp.rx_packets = stats->rx_packets;
552 tmp.rx_bytes = stats->rx_bytes;
553 tmp.tx_packets = stats->tx_packets;
554 tmp.tx_bytes = stats->tx_bytes;
555 } while (u64_stats_fetch_retry_irq(&stats->syncp, start));
557 s->rx_packets += tmp.rx_packets;
558 s->rx_bytes += tmp.rx_bytes;
559 s->tx_packets += tmp.tx_packets;
560 s->tx_bytes += tmp.tx_bytes;
563 s->rx_dropped = dev->stats.rx_dropped;
564 s->tx_dropped = dev->stats.tx_dropped;
567 static int xfrmi_get_iflink(const struct net_device *dev)
569 struct xfrm_if *xi = netdev_priv(dev);
575 static const struct net_device_ops xfrmi_netdev_ops = {
576 .ndo_init = xfrmi_dev_init,
577 .ndo_uninit = xfrmi_dev_uninit,
578 .ndo_start_xmit = xfrmi_xmit,
579 .ndo_get_stats64 = xfrmi_get_stats64,
580 .ndo_get_iflink = xfrmi_get_iflink,
583 static void xfrmi_dev_setup(struct net_device *dev)
585 dev->netdev_ops = &xfrmi_netdev_ops;
586 dev->type = ARPHRD_NONE;
587 dev->mtu = ETH_DATA_LEN;
588 dev->min_mtu = ETH_MIN_MTU;
589 dev->max_mtu = IP_MAX_MTU;
590 dev->flags = IFF_NOARP;
591 dev->needs_free_netdev = true;
592 dev->priv_destructor = xfrmi_dev_free;
595 eth_broadcast_addr(dev->broadcast);
598 static int xfrmi_dev_init(struct net_device *dev)
600 struct xfrm_if *xi = netdev_priv(dev);
601 struct net_device *phydev = __dev_get_by_index(xi->net, xi->p.link);
604 dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
608 err = gro_cells_init(&xi->gro_cells, dev);
610 free_percpu(dev->tstats);
614 dev->features |= NETIF_F_LLTX;
617 dev->needed_headroom = phydev->needed_headroom;
618 dev->needed_tailroom = phydev->needed_tailroom;
620 if (is_zero_ether_addr(dev->dev_addr))
621 eth_hw_addr_inherit(dev, phydev);
622 if (is_zero_ether_addr(dev->broadcast))
623 memcpy(dev->broadcast, phydev->broadcast,
626 eth_hw_addr_random(dev);
627 eth_broadcast_addr(dev->broadcast);
633 static int xfrmi_validate(struct nlattr *tb[], struct nlattr *data[],
634 struct netlink_ext_ack *extack)
639 static void xfrmi_netlink_parms(struct nlattr *data[],
640 struct xfrm_if_parms *parms)
642 memset(parms, 0, sizeof(*parms));
647 if (data[IFLA_XFRM_LINK])
648 parms->link = nla_get_u32(data[IFLA_XFRM_LINK]);
650 if (data[IFLA_XFRM_IF_ID])
651 parms->if_id = nla_get_u32(data[IFLA_XFRM_IF_ID]);
654 static int xfrmi_newlink(struct net *src_net, struct net_device *dev,
655 struct nlattr *tb[], struct nlattr *data[],
656 struct netlink_ext_ack *extack)
658 struct net *net = dev_net(dev);
659 struct xfrm_if_parms p;
663 xfrmi_netlink_parms(data, &p);
664 xi = xfrmi_locate(net, &p);
668 xi = netdev_priv(dev);
673 err = xfrmi_create(dev);
677 static void xfrmi_dellink(struct net_device *dev, struct list_head *head)
679 unregister_netdevice_queue(dev, head);
682 static int xfrmi_changelink(struct net_device *dev, struct nlattr *tb[],
683 struct nlattr *data[],
684 struct netlink_ext_ack *extack)
686 struct xfrm_if *xi = netdev_priv(dev);
687 struct net *net = xi->net;
688 struct xfrm_if_parms p;
690 xfrmi_netlink_parms(data, &p);
691 xi = xfrmi_locate(net, &p);
693 xi = netdev_priv(dev);
699 return xfrmi_update(xi, &p);
702 static size_t xfrmi_get_size(const struct net_device *dev)
707 /* IFLA_XFRM_IF_ID */
712 static int xfrmi_fill_info(struct sk_buff *skb, const struct net_device *dev)
714 struct xfrm_if *xi = netdev_priv(dev);
715 struct xfrm_if_parms *parm = &xi->p;
717 if (nla_put_u32(skb, IFLA_XFRM_LINK, parm->link) ||
718 nla_put_u32(skb, IFLA_XFRM_IF_ID, parm->if_id))
719 goto nla_put_failure;
726 static struct net *xfrmi_get_link_net(const struct net_device *dev)
728 struct xfrm_if *xi = netdev_priv(dev);
733 static const struct nla_policy xfrmi_policy[IFLA_XFRM_MAX + 1] = {
734 [IFLA_XFRM_LINK] = { .type = NLA_U32 },
735 [IFLA_XFRM_IF_ID] = { .type = NLA_U32 },
738 static struct rtnl_link_ops xfrmi_link_ops __read_mostly = {
740 .maxtype = IFLA_XFRM_MAX,
741 .policy = xfrmi_policy,
742 .priv_size = sizeof(struct xfrm_if),
743 .setup = xfrmi_dev_setup,
744 .validate = xfrmi_validate,
745 .newlink = xfrmi_newlink,
746 .dellink = xfrmi_dellink,
747 .changelink = xfrmi_changelink,
748 .get_size = xfrmi_get_size,
749 .fill_info = xfrmi_fill_info,
750 .get_link_net = xfrmi_get_link_net,
753 static struct pernet_operations xfrmi_net_ops = {
755 .size = sizeof(struct xfrmi_net),
758 static struct xfrm6_protocol xfrmi_esp6_protocol __read_mostly = {
759 .handler = xfrm6_rcv,
760 .cb_handler = xfrmi_rcv_cb,
761 .err_handler = xfrmi6_err,
765 static struct xfrm6_protocol xfrmi_ah6_protocol __read_mostly = {
766 .handler = xfrm6_rcv,
767 .cb_handler = xfrmi_rcv_cb,
768 .err_handler = xfrmi6_err,
772 static struct xfrm6_protocol xfrmi_ipcomp6_protocol __read_mostly = {
773 .handler = xfrm6_rcv,
774 .cb_handler = xfrmi_rcv_cb,
775 .err_handler = xfrmi6_err,
779 static struct xfrm4_protocol xfrmi_esp4_protocol __read_mostly = {
780 .handler = xfrm4_rcv,
781 .input_handler = xfrm_input,
782 .cb_handler = xfrmi_rcv_cb,
783 .err_handler = xfrmi4_err,
787 static struct xfrm4_protocol xfrmi_ah4_protocol __read_mostly = {
788 .handler = xfrm4_rcv,
789 .input_handler = xfrm_input,
790 .cb_handler = xfrmi_rcv_cb,
791 .err_handler = xfrmi4_err,
795 static struct xfrm4_protocol xfrmi_ipcomp4_protocol __read_mostly = {
796 .handler = xfrm4_rcv,
797 .input_handler = xfrm_input,
798 .cb_handler = xfrmi_rcv_cb,
799 .err_handler = xfrmi4_err,
803 static int __init xfrmi4_init(void)
807 err = xfrm4_protocol_register(&xfrmi_esp4_protocol, IPPROTO_ESP);
809 goto xfrm_proto_esp_failed;
810 err = xfrm4_protocol_register(&xfrmi_ah4_protocol, IPPROTO_AH);
812 goto xfrm_proto_ah_failed;
813 err = xfrm4_protocol_register(&xfrmi_ipcomp4_protocol, IPPROTO_COMP);
815 goto xfrm_proto_comp_failed;
819 xfrm_proto_comp_failed:
820 xfrm4_protocol_deregister(&xfrmi_ah4_protocol, IPPROTO_AH);
821 xfrm_proto_ah_failed:
822 xfrm4_protocol_deregister(&xfrmi_esp4_protocol, IPPROTO_ESP);
823 xfrm_proto_esp_failed:
827 static void xfrmi4_fini(void)
829 xfrm4_protocol_deregister(&xfrmi_ipcomp4_protocol, IPPROTO_COMP);
830 xfrm4_protocol_deregister(&xfrmi_ah4_protocol, IPPROTO_AH);
831 xfrm4_protocol_deregister(&xfrmi_esp4_protocol, IPPROTO_ESP);
834 static int __init xfrmi6_init(void)
838 err = xfrm6_protocol_register(&xfrmi_esp6_protocol, IPPROTO_ESP);
840 goto xfrm_proto_esp_failed;
841 err = xfrm6_protocol_register(&xfrmi_ah6_protocol, IPPROTO_AH);
843 goto xfrm_proto_ah_failed;
844 err = xfrm6_protocol_register(&xfrmi_ipcomp6_protocol, IPPROTO_COMP);
846 goto xfrm_proto_comp_failed;
850 xfrm_proto_comp_failed:
851 xfrm6_protocol_deregister(&xfrmi_ah6_protocol, IPPROTO_AH);
852 xfrm_proto_ah_failed:
853 xfrm6_protocol_deregister(&xfrmi_esp6_protocol, IPPROTO_ESP);
854 xfrm_proto_esp_failed:
858 static void xfrmi6_fini(void)
860 xfrm6_protocol_deregister(&xfrmi_ipcomp6_protocol, IPPROTO_COMP);
861 xfrm6_protocol_deregister(&xfrmi_ah6_protocol, IPPROTO_AH);
862 xfrm6_protocol_deregister(&xfrmi_esp6_protocol, IPPROTO_ESP);
865 static const struct xfrm_if_cb xfrm_if_cb = {
866 .decode_session = xfrmi_decode_session,
869 static int __init xfrmi_init(void)
874 pr_info("IPsec XFRM device driver\n");
876 msg = "tunnel device";
877 err = register_pernet_device(&xfrmi_net_ops);
879 goto pernet_dev_failed;
881 msg = "xfrm4 protocols";
886 msg = "xfrm6 protocols";
892 msg = "netlink interface";
893 err = rtnl_link_register(&xfrmi_link_ops);
895 goto rtnl_link_failed;
897 xfrm_if_register_cb(&xfrm_if_cb);
906 unregister_pernet_device(&xfrmi_net_ops);
908 pr_err("xfrmi init: failed to register %s\n", msg);
912 static void __exit xfrmi_fini(void)
914 xfrm_if_unregister_cb();
915 rtnl_link_unregister(&xfrmi_link_ops);
918 unregister_pernet_device(&xfrmi_net_ops);
921 module_init(xfrmi_init);
922 module_exit(xfrmi_fini);
923 MODULE_LICENSE("GPL");
924 MODULE_ALIAS_RTNL_LINK("xfrm");
925 MODULE_ALIAS_NETDEV("xfrm0");
926 MODULE_AUTHOR("Steffen Klassert");
927 MODULE_DESCRIPTION("XFRM virtual interface");