1 // SPDX-License-Identifier: GPL-2.0
3 * XFRM virtual interface
5 * Copyright (C) 2018 secunet Security Networks AG
8 * Steffen Klassert <steffen.klassert@secunet.com>
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);
148 xfrmi_link(xfrmn, xi);
156 static struct xfrm_if *xfrmi_locate(struct net *net, struct xfrm_if_parms *p)
158 struct xfrm_if __rcu **xip;
160 struct xfrmi_net *xfrmn = net_generic(net, xfrmi_net_id);
162 for (xip = &xfrmn->xfrmi[0];
163 (xi = rtnl_dereference(*xip)) != NULL;
165 if (xi->p.if_id == p->if_id)
171 static void xfrmi_dev_uninit(struct net_device *dev)
173 struct xfrm_if *xi = netdev_priv(dev);
174 struct xfrmi_net *xfrmn = net_generic(xi->net, xfrmi_net_id);
176 xfrmi_unlink(xfrmn, xi);
179 static void xfrmi_scrub_packet(struct sk_buff *skb, bool xnet)
182 skb->pkt_type = PACKET_HOST;
198 static int xfrmi_rcv_cb(struct sk_buff *skb, int err)
200 const struct xfrm_mode *inner_mode;
201 struct pcpu_sw_netstats *tstats;
202 struct net_device *dev;
203 struct xfrm_state *x;
207 if (err && !secpath_exists(skb))
210 x = xfrm_input_state(skb);
212 xi = xfrmi_lookup(xs_net(x), x);
220 dev->stats.rx_errors++;
221 dev->stats.rx_dropped++;
226 xnet = !net_eq(xi->net, dev_net(skb->dev));
229 inner_mode = &x->inner_mode;
231 if (x->sel.family == AF_UNSPEC) {
232 inner_mode = xfrm_ip2inner_mode(x, XFRM_MODE_SKB_CB(skb)->protocol);
233 if (inner_mode == NULL) {
234 XFRM_INC_STATS(dev_net(skb->dev),
235 LINUX_MIB_XFRMINSTATEMODEERROR);
240 if (!xfrm_policy_check(NULL, XFRM_POLICY_IN, skb,
245 xfrmi_scrub_packet(skb, xnet);
247 tstats = this_cpu_ptr(dev->tstats);
249 u64_stats_update_begin(&tstats->syncp);
250 tstats->rx_packets++;
251 tstats->rx_bytes += skb->len;
252 u64_stats_update_end(&tstats->syncp);
258 xfrmi_xmit2(struct sk_buff *skb, struct net_device *dev, struct flowi *fl)
260 struct xfrm_if *xi = netdev_priv(dev);
261 struct net_device_stats *stats = &xi->dev->stats;
262 struct dst_entry *dst = skb_dst(skb);
263 unsigned int length = skb->len;
264 struct net_device *tdev;
265 struct xfrm_state *x;
270 dst = xfrm_lookup_with_ifid(xi->net, dst, fl, NULL, 0, xi->p.if_id);
274 goto tx_err_link_failure;
279 goto tx_err_link_failure;
281 if (x->if_id != xi->p.if_id)
282 goto tx_err_link_failure;
288 net_warn_ratelimited("%s: Local routing loop detected!\n",
290 goto tx_err_dst_release;
294 if (!skb->ignore_df && skb->len > mtu) {
295 skb_dst_update_pmtu_no_confirm(skb, mtu);
297 if (skb->protocol == htons(ETH_P_IPV6)) {
298 if (mtu < IPV6_MIN_MTU)
301 icmpv6_ndo_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
303 icmp_ndo_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
311 xfrmi_scrub_packet(skb, !net_eq(xi->net, dev_net(dev)));
312 skb_dst_set(skb, dst);
315 err = dst_output(xi->net, skb->sk, skb);
316 if (net_xmit_eval(err) == 0) {
317 struct pcpu_sw_netstats *tstats = this_cpu_ptr(dev->tstats);
319 u64_stats_update_begin(&tstats->syncp);
320 tstats->tx_bytes += length;
321 tstats->tx_packets++;
322 u64_stats_update_end(&tstats->syncp);
325 stats->tx_aborted_errors++;
330 stats->tx_carrier_errors++;
331 dst_link_failure(skb);
337 static netdev_tx_t xfrmi_xmit(struct sk_buff *skb, struct net_device *dev)
339 struct xfrm_if *xi = netdev_priv(dev);
340 struct net_device_stats *stats = &xi->dev->stats;
341 struct dst_entry *dst = skb_dst(skb);
345 memset(&fl, 0, sizeof(fl));
347 switch (skb->protocol) {
348 case htons(ETH_P_IPV6):
349 xfrm_decode_session(skb, &fl, AF_INET6);
350 memset(IP6CB(skb), 0, sizeof(*IP6CB(skb)));
352 fl.u.ip6.flowi6_oif = dev->ifindex;
353 fl.u.ip6.flowi6_flags |= FLOWI_FLAG_ANYSRC;
354 dst = ip6_route_output(dev_net(dev), NULL, &fl.u.ip6);
357 stats->tx_carrier_errors++;
360 skb_dst_set(skb, dst);
363 case htons(ETH_P_IP):
364 xfrm_decode_session(skb, &fl, AF_INET);
365 memset(IPCB(skb), 0, sizeof(*IPCB(skb)));
369 fl.u.ip4.flowi4_oif = dev->ifindex;
370 fl.u.ip4.flowi4_flags |= FLOWI_FLAG_ANYSRC;
371 rt = __ip_route_output_key(dev_net(dev), &fl.u.ip4);
373 stats->tx_carrier_errors++;
376 skb_dst_set(skb, &rt->dst);
383 fl.flowi_oif = xi->p.link;
385 ret = xfrmi_xmit2(skb, dev, &fl);
398 static int xfrmi4_err(struct sk_buff *skb, u32 info)
400 const struct iphdr *iph = (const struct iphdr *)skb->data;
401 struct net *net = dev_net(skb->dev);
402 int protocol = iph->protocol;
403 struct ip_comp_hdr *ipch;
404 struct ip_esp_hdr *esph;
405 struct ip_auth_hdr *ah ;
406 struct xfrm_state *x;
412 esph = (struct ip_esp_hdr *)(skb->data+(iph->ihl<<2));
416 ah = (struct ip_auth_hdr *)(skb->data+(iph->ihl<<2));
420 ipch = (struct ip_comp_hdr *)(skb->data+(iph->ihl<<2));
421 spi = htonl(ntohs(ipch->cpi));
427 switch (icmp_hdr(skb)->type) {
428 case ICMP_DEST_UNREACH:
429 if (icmp_hdr(skb)->code != ICMP_FRAG_NEEDED)
437 x = xfrm_state_lookup(net, skb->mark, (const xfrm_address_t *)&iph->daddr,
438 spi, protocol, AF_INET);
442 xi = xfrmi_lookup(net, x);
448 if (icmp_hdr(skb)->type == ICMP_DEST_UNREACH)
449 ipv4_update_pmtu(skb, net, info, 0, protocol);
451 ipv4_redirect(skb, net, 0, protocol);
457 static int xfrmi6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
458 u8 type, u8 code, int offset, __be32 info)
460 const struct ipv6hdr *iph = (const struct ipv6hdr *)skb->data;
461 struct net *net = dev_net(skb->dev);
462 int protocol = iph->nexthdr;
463 struct ip_comp_hdr *ipch;
464 struct ip_esp_hdr *esph;
465 struct ip_auth_hdr *ah;
466 struct xfrm_state *x;
472 esph = (struct ip_esp_hdr *)(skb->data + offset);
476 ah = (struct ip_auth_hdr *)(skb->data + offset);
480 ipch = (struct ip_comp_hdr *)(skb->data + offset);
481 spi = htonl(ntohs(ipch->cpi));
487 if (type != ICMPV6_PKT_TOOBIG &&
488 type != NDISC_REDIRECT)
491 x = xfrm_state_lookup(net, skb->mark, (const xfrm_address_t *)&iph->daddr,
492 spi, protocol, AF_INET6);
496 xi = xfrmi_lookup(net, x);
502 if (type == NDISC_REDIRECT)
503 ip6_redirect(skb, net, skb->dev->ifindex, 0,
504 sock_net_uid(net, NULL));
506 ip6_update_pmtu(skb, net, info, 0, 0, sock_net_uid(net, NULL));
512 static int xfrmi_change(struct xfrm_if *xi, const struct xfrm_if_parms *p)
514 if (xi->p.link != p->link)
517 xi->p.if_id = p->if_id;
522 static int xfrmi_update(struct xfrm_if *xi, struct xfrm_if_parms *p)
524 struct net *net = xi->net;
525 struct xfrmi_net *xfrmn = net_generic(net, xfrmi_net_id);
528 xfrmi_unlink(xfrmn, xi);
530 err = xfrmi_change(xi, p);
531 xfrmi_link(xfrmn, xi);
532 netdev_state_change(xi->dev);
536 static void xfrmi_get_stats64(struct net_device *dev,
537 struct rtnl_link_stats64 *s)
541 for_each_possible_cpu(cpu) {
542 struct pcpu_sw_netstats *stats;
543 struct pcpu_sw_netstats tmp;
546 stats = per_cpu_ptr(dev->tstats, cpu);
548 start = u64_stats_fetch_begin_irq(&stats->syncp);
549 tmp.rx_packets = stats->rx_packets;
550 tmp.rx_bytes = stats->rx_bytes;
551 tmp.tx_packets = stats->tx_packets;
552 tmp.tx_bytes = stats->tx_bytes;
553 } while (u64_stats_fetch_retry_irq(&stats->syncp, start));
555 s->rx_packets += tmp.rx_packets;
556 s->rx_bytes += tmp.rx_bytes;
557 s->tx_packets += tmp.tx_packets;
558 s->tx_bytes += tmp.tx_bytes;
561 s->rx_dropped = dev->stats.rx_dropped;
562 s->tx_dropped = dev->stats.tx_dropped;
565 static int xfrmi_get_iflink(const struct net_device *dev)
567 struct xfrm_if *xi = netdev_priv(dev);
573 static const struct net_device_ops xfrmi_netdev_ops = {
574 .ndo_init = xfrmi_dev_init,
575 .ndo_uninit = xfrmi_dev_uninit,
576 .ndo_start_xmit = xfrmi_xmit,
577 .ndo_get_stats64 = xfrmi_get_stats64,
578 .ndo_get_iflink = xfrmi_get_iflink,
581 static void xfrmi_dev_setup(struct net_device *dev)
583 dev->netdev_ops = &xfrmi_netdev_ops;
584 dev->type = ARPHRD_NONE;
585 dev->mtu = ETH_DATA_LEN;
586 dev->min_mtu = ETH_MIN_MTU;
587 dev->max_mtu = IP_MAX_MTU;
588 dev->flags = IFF_NOARP;
589 dev->needs_free_netdev = true;
590 dev->priv_destructor = xfrmi_dev_free;
593 eth_broadcast_addr(dev->broadcast);
596 static int xfrmi_dev_init(struct net_device *dev)
598 struct xfrm_if *xi = netdev_priv(dev);
599 struct net_device *phydev = __dev_get_by_index(xi->net, xi->p.link);
602 dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
606 err = gro_cells_init(&xi->gro_cells, dev);
608 free_percpu(dev->tstats);
612 dev->features |= NETIF_F_LLTX;
615 dev->needed_headroom = phydev->needed_headroom;
616 dev->needed_tailroom = phydev->needed_tailroom;
618 if (is_zero_ether_addr(dev->dev_addr))
619 eth_hw_addr_inherit(dev, phydev);
620 if (is_zero_ether_addr(dev->broadcast))
621 memcpy(dev->broadcast, phydev->broadcast,
624 eth_hw_addr_random(dev);
625 eth_broadcast_addr(dev->broadcast);
631 static int xfrmi_validate(struct nlattr *tb[], struct nlattr *data[],
632 struct netlink_ext_ack *extack)
637 static void xfrmi_netlink_parms(struct nlattr *data[],
638 struct xfrm_if_parms *parms)
640 memset(parms, 0, sizeof(*parms));
645 if (data[IFLA_XFRM_LINK])
646 parms->link = nla_get_u32(data[IFLA_XFRM_LINK]);
648 if (data[IFLA_XFRM_IF_ID])
649 parms->if_id = nla_get_u32(data[IFLA_XFRM_IF_ID]);
652 static int xfrmi_newlink(struct net *src_net, struct net_device *dev,
653 struct nlattr *tb[], struct nlattr *data[],
654 struct netlink_ext_ack *extack)
656 struct net *net = dev_net(dev);
657 struct xfrm_if_parms p;
661 xfrmi_netlink_parms(data, &p);
662 xi = xfrmi_locate(net, &p);
666 xi = netdev_priv(dev);
671 err = xfrmi_create(dev);
675 static void xfrmi_dellink(struct net_device *dev, struct list_head *head)
677 unregister_netdevice_queue(dev, head);
680 static int xfrmi_changelink(struct net_device *dev, struct nlattr *tb[],
681 struct nlattr *data[],
682 struct netlink_ext_ack *extack)
684 struct xfrm_if *xi = netdev_priv(dev);
685 struct net *net = xi->net;
686 struct xfrm_if_parms p;
688 xfrmi_netlink_parms(data, &p);
689 xi = xfrmi_locate(net, &p);
691 xi = netdev_priv(dev);
697 return xfrmi_update(xi, &p);
700 static size_t xfrmi_get_size(const struct net_device *dev)
705 /* IFLA_XFRM_IF_ID */
710 static int xfrmi_fill_info(struct sk_buff *skb, const struct net_device *dev)
712 struct xfrm_if *xi = netdev_priv(dev);
713 struct xfrm_if_parms *parm = &xi->p;
715 if (nla_put_u32(skb, IFLA_XFRM_LINK, parm->link) ||
716 nla_put_u32(skb, IFLA_XFRM_IF_ID, parm->if_id))
717 goto nla_put_failure;
724 static struct net *xfrmi_get_link_net(const struct net_device *dev)
726 struct xfrm_if *xi = netdev_priv(dev);
731 static const struct nla_policy xfrmi_policy[IFLA_XFRM_MAX + 1] = {
732 [IFLA_XFRM_LINK] = { .type = NLA_U32 },
733 [IFLA_XFRM_IF_ID] = { .type = NLA_U32 },
736 static struct rtnl_link_ops xfrmi_link_ops __read_mostly = {
738 .maxtype = IFLA_XFRM_MAX,
739 .policy = xfrmi_policy,
740 .priv_size = sizeof(struct xfrm_if),
741 .setup = xfrmi_dev_setup,
742 .validate = xfrmi_validate,
743 .newlink = xfrmi_newlink,
744 .dellink = xfrmi_dellink,
745 .changelink = xfrmi_changelink,
746 .get_size = xfrmi_get_size,
747 .fill_info = xfrmi_fill_info,
748 .get_link_net = xfrmi_get_link_net,
751 static void __net_exit xfrmi_exit_batch_net(struct list_head *net_exit_list)
757 list_for_each_entry(net, net_exit_list, exit_list) {
758 struct xfrmi_net *xfrmn = net_generic(net, xfrmi_net_id);
759 struct xfrm_if __rcu **xip;
762 for (xip = &xfrmn->xfrmi[0];
763 (xi = rtnl_dereference(*xip)) != NULL;
765 unregister_netdevice_queue(xi->dev, &list);
767 unregister_netdevice_many(&list);
771 static struct pernet_operations xfrmi_net_ops = {
772 .exit_batch = xfrmi_exit_batch_net,
774 .size = sizeof(struct xfrmi_net),
777 static struct xfrm6_protocol xfrmi_esp6_protocol __read_mostly = {
778 .handler = xfrm6_rcv,
779 .input_handler = xfrm_input,
780 .cb_handler = xfrmi_rcv_cb,
781 .err_handler = xfrmi6_err,
785 static struct xfrm6_protocol xfrmi_ah6_protocol __read_mostly = {
786 .handler = xfrm6_rcv,
787 .input_handler = xfrm_input,
788 .cb_handler = xfrmi_rcv_cb,
789 .err_handler = xfrmi6_err,
793 static struct xfrm6_protocol xfrmi_ipcomp6_protocol __read_mostly = {
794 .handler = xfrm6_rcv,
795 .input_handler = xfrm_input,
796 .cb_handler = xfrmi_rcv_cb,
797 .err_handler = xfrmi6_err,
801 static struct xfrm4_protocol xfrmi_esp4_protocol __read_mostly = {
802 .handler = xfrm4_rcv,
803 .input_handler = xfrm_input,
804 .cb_handler = xfrmi_rcv_cb,
805 .err_handler = xfrmi4_err,
809 static struct xfrm4_protocol xfrmi_ah4_protocol __read_mostly = {
810 .handler = xfrm4_rcv,
811 .input_handler = xfrm_input,
812 .cb_handler = xfrmi_rcv_cb,
813 .err_handler = xfrmi4_err,
817 static struct xfrm4_protocol xfrmi_ipcomp4_protocol __read_mostly = {
818 .handler = xfrm4_rcv,
819 .input_handler = xfrm_input,
820 .cb_handler = xfrmi_rcv_cb,
821 .err_handler = xfrmi4_err,
825 static int __init xfrmi4_init(void)
829 err = xfrm4_protocol_register(&xfrmi_esp4_protocol, IPPROTO_ESP);
831 goto xfrm_proto_esp_failed;
832 err = xfrm4_protocol_register(&xfrmi_ah4_protocol, IPPROTO_AH);
834 goto xfrm_proto_ah_failed;
835 err = xfrm4_protocol_register(&xfrmi_ipcomp4_protocol, IPPROTO_COMP);
837 goto xfrm_proto_comp_failed;
841 xfrm_proto_comp_failed:
842 xfrm4_protocol_deregister(&xfrmi_ah4_protocol, IPPROTO_AH);
843 xfrm_proto_ah_failed:
844 xfrm4_protocol_deregister(&xfrmi_esp4_protocol, IPPROTO_ESP);
845 xfrm_proto_esp_failed:
849 static void xfrmi4_fini(void)
851 xfrm4_protocol_deregister(&xfrmi_ipcomp4_protocol, IPPROTO_COMP);
852 xfrm4_protocol_deregister(&xfrmi_ah4_protocol, IPPROTO_AH);
853 xfrm4_protocol_deregister(&xfrmi_esp4_protocol, IPPROTO_ESP);
856 static int __init xfrmi6_init(void)
860 err = xfrm6_protocol_register(&xfrmi_esp6_protocol, IPPROTO_ESP);
862 goto xfrm_proto_esp_failed;
863 err = xfrm6_protocol_register(&xfrmi_ah6_protocol, IPPROTO_AH);
865 goto xfrm_proto_ah_failed;
866 err = xfrm6_protocol_register(&xfrmi_ipcomp6_protocol, IPPROTO_COMP);
868 goto xfrm_proto_comp_failed;
872 xfrm_proto_comp_failed:
873 xfrm6_protocol_deregister(&xfrmi_ah6_protocol, IPPROTO_AH);
874 xfrm_proto_ah_failed:
875 xfrm6_protocol_deregister(&xfrmi_esp6_protocol, IPPROTO_ESP);
876 xfrm_proto_esp_failed:
880 static void xfrmi6_fini(void)
882 xfrm6_protocol_deregister(&xfrmi_ipcomp6_protocol, IPPROTO_COMP);
883 xfrm6_protocol_deregister(&xfrmi_ah6_protocol, IPPROTO_AH);
884 xfrm6_protocol_deregister(&xfrmi_esp6_protocol, IPPROTO_ESP);
887 static const struct xfrm_if_cb xfrm_if_cb = {
888 .decode_session = xfrmi_decode_session,
891 static int __init xfrmi_init(void)
896 pr_info("IPsec XFRM device driver\n");
898 msg = "tunnel device";
899 err = register_pernet_device(&xfrmi_net_ops);
901 goto pernet_dev_failed;
903 msg = "xfrm4 protocols";
908 msg = "xfrm6 protocols";
914 msg = "netlink interface";
915 err = rtnl_link_register(&xfrmi_link_ops);
917 goto rtnl_link_failed;
919 xfrm_if_register_cb(&xfrm_if_cb);
928 unregister_pernet_device(&xfrmi_net_ops);
930 pr_err("xfrmi init: failed to register %s\n", msg);
934 static void __exit xfrmi_fini(void)
936 xfrm_if_unregister_cb();
937 rtnl_link_unregister(&xfrmi_link_ops);
940 unregister_pernet_device(&xfrmi_net_ops);
943 module_init(xfrmi_init);
944 module_exit(xfrmi_fini);
945 MODULE_LICENSE("GPL");
946 MODULE_ALIAS_RTNL_LINK("xfrm");
947 MODULE_ALIAS_NETDEV("xfrm0");
948 MODULE_AUTHOR("Steffen Klassert");
949 MODULE_DESCRIPTION("XFRM virtual interface");