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 strcpy(xi->p.name, dev->name);
151 xfrmi_link(xfrmn, xi);
159 static struct xfrm_if *xfrmi_locate(struct net *net, struct xfrm_if_parms *p)
161 struct xfrm_if __rcu **xip;
163 struct xfrmi_net *xfrmn = net_generic(net, xfrmi_net_id);
165 for (xip = &xfrmn->xfrmi[0];
166 (xi = rtnl_dereference(*xip)) != NULL;
168 if (xi->p.if_id == p->if_id)
174 static void xfrmi_dev_uninit(struct net_device *dev)
176 struct xfrm_if *xi = netdev_priv(dev);
177 struct xfrmi_net *xfrmn = net_generic(xi->net, xfrmi_net_id);
179 xfrmi_unlink(xfrmn, xi);
184 static void xfrmi_scrub_packet(struct sk_buff *skb, bool xnet)
187 skb->pkt_type = PACKET_HOST;
203 static int xfrmi_rcv_cb(struct sk_buff *skb, int err)
205 const struct xfrm_mode *inner_mode;
206 struct pcpu_sw_netstats *tstats;
207 struct net_device *dev;
208 struct xfrm_state *x;
212 if (err && !secpath_exists(skb))
215 x = xfrm_input_state(skb);
217 xi = xfrmi_lookup(xs_net(x), x);
225 dev->stats.rx_errors++;
226 dev->stats.rx_dropped++;
231 xnet = !net_eq(xi->net, dev_net(skb->dev));
234 inner_mode = &x->inner_mode;
236 if (x->sel.family == AF_UNSPEC) {
237 inner_mode = xfrm_ip2inner_mode(x, XFRM_MODE_SKB_CB(skb)->protocol);
238 if (inner_mode == NULL) {
239 XFRM_INC_STATS(dev_net(skb->dev),
240 LINUX_MIB_XFRMINSTATEMODEERROR);
245 if (!xfrm_policy_check(NULL, XFRM_POLICY_IN, skb,
250 xfrmi_scrub_packet(skb, xnet);
252 tstats = this_cpu_ptr(dev->tstats);
254 u64_stats_update_begin(&tstats->syncp);
255 tstats->rx_packets++;
256 tstats->rx_bytes += skb->len;
257 u64_stats_update_end(&tstats->syncp);
263 xfrmi_xmit2(struct sk_buff *skb, struct net_device *dev, struct flowi *fl)
265 struct xfrm_if *xi = netdev_priv(dev);
266 struct net_device_stats *stats = &xi->dev->stats;
267 struct dst_entry *dst = skb_dst(skb);
268 unsigned int length = skb->len;
269 struct net_device *tdev;
270 struct xfrm_state *x;
275 goto tx_err_link_failure;
278 dst = xfrm_lookup_with_ifid(xi->net, dst, fl, NULL, 0, xi->p.if_id);
282 goto tx_err_link_failure;
287 goto tx_err_link_failure;
289 if (x->if_id != xi->p.if_id)
290 goto tx_err_link_failure;
296 net_warn_ratelimited("%s: Local routing loop detected!\n",
298 goto tx_err_dst_release;
302 if (!skb->ignore_df && skb->len > mtu) {
303 skb_dst_update_pmtu(skb, mtu);
305 if (skb->protocol == htons(ETH_P_IPV6)) {
306 if (mtu < IPV6_MIN_MTU)
309 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
311 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
319 xfrmi_scrub_packet(skb, !net_eq(xi->net, dev_net(dev)));
320 skb_dst_set(skb, dst);
323 err = dst_output(xi->net, skb->sk, skb);
324 if (net_xmit_eval(err) == 0) {
325 struct pcpu_sw_netstats *tstats = this_cpu_ptr(dev->tstats);
327 u64_stats_update_begin(&tstats->syncp);
328 tstats->tx_bytes += length;
329 tstats->tx_packets++;
330 u64_stats_update_end(&tstats->syncp);
333 stats->tx_aborted_errors++;
338 stats->tx_carrier_errors++;
339 dst_link_failure(skb);
345 static netdev_tx_t xfrmi_xmit(struct sk_buff *skb, struct net_device *dev)
347 struct xfrm_if *xi = netdev_priv(dev);
348 struct net_device_stats *stats = &xi->dev->stats;
352 memset(&fl, 0, sizeof(fl));
354 switch (skb->protocol) {
355 case htons(ETH_P_IPV6):
356 xfrm_decode_session(skb, &fl, AF_INET6);
357 memset(IP6CB(skb), 0, sizeof(*IP6CB(skb)));
359 case htons(ETH_P_IP):
360 xfrm_decode_session(skb, &fl, AF_INET);
361 memset(IPCB(skb), 0, sizeof(*IPCB(skb)));
367 fl.flowi_oif = xi->phydev->ifindex;
369 ret = xfrmi_xmit2(skb, dev, &fl);
382 static int xfrmi4_err(struct sk_buff *skb, u32 info)
384 const struct iphdr *iph = (const struct iphdr *)skb->data;
385 struct net *net = dev_net(skb->dev);
386 int protocol = iph->protocol;
387 struct ip_comp_hdr *ipch;
388 struct ip_esp_hdr *esph;
389 struct ip_auth_hdr *ah ;
390 struct xfrm_state *x;
396 esph = (struct ip_esp_hdr *)(skb->data+(iph->ihl<<2));
400 ah = (struct ip_auth_hdr *)(skb->data+(iph->ihl<<2));
404 ipch = (struct ip_comp_hdr *)(skb->data+(iph->ihl<<2));
405 spi = htonl(ntohs(ipch->cpi));
411 switch (icmp_hdr(skb)->type) {
412 case ICMP_DEST_UNREACH:
413 if (icmp_hdr(skb)->code != ICMP_FRAG_NEEDED)
421 x = xfrm_state_lookup(net, skb->mark, (const xfrm_address_t *)&iph->daddr,
422 spi, protocol, AF_INET);
426 xi = xfrmi_lookup(net, x);
432 if (icmp_hdr(skb)->type == ICMP_DEST_UNREACH)
433 ipv4_update_pmtu(skb, net, info, 0, protocol);
435 ipv4_redirect(skb, net, 0, protocol);
441 static int xfrmi6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
442 u8 type, u8 code, int offset, __be32 info)
444 const struct ipv6hdr *iph = (const struct ipv6hdr *)skb->data;
445 struct net *net = dev_net(skb->dev);
446 int protocol = iph->nexthdr;
447 struct ip_comp_hdr *ipch;
448 struct ip_esp_hdr *esph;
449 struct ip_auth_hdr *ah;
450 struct xfrm_state *x;
456 esph = (struct ip_esp_hdr *)(skb->data + offset);
460 ah = (struct ip_auth_hdr *)(skb->data + offset);
464 ipch = (struct ip_comp_hdr *)(skb->data + offset);
465 spi = htonl(ntohs(ipch->cpi));
471 if (type != ICMPV6_PKT_TOOBIG &&
472 type != NDISC_REDIRECT)
475 x = xfrm_state_lookup(net, skb->mark, (const xfrm_address_t *)&iph->daddr,
476 spi, protocol, AF_INET6);
480 xi = xfrmi_lookup(net, x);
486 if (type == NDISC_REDIRECT)
487 ip6_redirect(skb, net, skb->dev->ifindex, 0,
488 sock_net_uid(net, NULL));
490 ip6_update_pmtu(skb, net, info, 0, 0, sock_net_uid(net, NULL));
496 static int xfrmi_change(struct xfrm_if *xi, const struct xfrm_if_parms *p)
498 if (xi->p.link != p->link)
501 xi->p.if_id = p->if_id;
506 static int xfrmi_update(struct xfrm_if *xi, struct xfrm_if_parms *p)
508 struct net *net = dev_net(xi->dev);
509 struct xfrmi_net *xfrmn = net_generic(net, xfrmi_net_id);
512 xfrmi_unlink(xfrmn, xi);
514 err = xfrmi_change(xi, p);
515 xfrmi_link(xfrmn, xi);
516 netdev_state_change(xi->dev);
520 static void xfrmi_get_stats64(struct net_device *dev,
521 struct rtnl_link_stats64 *s)
525 for_each_possible_cpu(cpu) {
526 struct pcpu_sw_netstats *stats;
527 struct pcpu_sw_netstats tmp;
530 stats = per_cpu_ptr(dev->tstats, cpu);
532 start = u64_stats_fetch_begin_irq(&stats->syncp);
533 tmp.rx_packets = stats->rx_packets;
534 tmp.rx_bytes = stats->rx_bytes;
535 tmp.tx_packets = stats->tx_packets;
536 tmp.tx_bytes = stats->tx_bytes;
537 } while (u64_stats_fetch_retry_irq(&stats->syncp, start));
539 s->rx_packets += tmp.rx_packets;
540 s->rx_bytes += tmp.rx_bytes;
541 s->tx_packets += tmp.tx_packets;
542 s->tx_bytes += tmp.tx_bytes;
545 s->rx_dropped = dev->stats.rx_dropped;
546 s->tx_dropped = dev->stats.tx_dropped;
549 static int xfrmi_get_iflink(const struct net_device *dev)
551 struct xfrm_if *xi = netdev_priv(dev);
553 return xi->phydev->ifindex;
557 static const struct net_device_ops xfrmi_netdev_ops = {
558 .ndo_init = xfrmi_dev_init,
559 .ndo_uninit = xfrmi_dev_uninit,
560 .ndo_start_xmit = xfrmi_xmit,
561 .ndo_get_stats64 = xfrmi_get_stats64,
562 .ndo_get_iflink = xfrmi_get_iflink,
565 static void xfrmi_dev_setup(struct net_device *dev)
567 dev->netdev_ops = &xfrmi_netdev_ops;
568 dev->type = ARPHRD_NONE;
569 dev->hard_header_len = ETH_HLEN;
570 dev->min_header_len = ETH_HLEN;
571 dev->mtu = ETH_DATA_LEN;
572 dev->min_mtu = ETH_MIN_MTU;
573 dev->max_mtu = ETH_DATA_LEN;
574 dev->addr_len = ETH_ALEN;
575 dev->flags = IFF_NOARP;
576 dev->needs_free_netdev = true;
577 dev->priv_destructor = xfrmi_dev_free;
581 static int xfrmi_dev_init(struct net_device *dev)
583 struct xfrm_if *xi = netdev_priv(dev);
584 struct net_device *phydev = xi->phydev;
587 dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
591 err = gro_cells_init(&xi->gro_cells, dev);
593 free_percpu(dev->tstats);
597 dev->features |= NETIF_F_LLTX;
599 dev->needed_headroom = phydev->needed_headroom;
600 dev->needed_tailroom = phydev->needed_tailroom;
602 if (is_zero_ether_addr(dev->dev_addr))
603 eth_hw_addr_inherit(dev, phydev);
604 if (is_zero_ether_addr(dev->broadcast))
605 memcpy(dev->broadcast, phydev->broadcast, dev->addr_len);
610 static int xfrmi_validate(struct nlattr *tb[], struct nlattr *data[],
611 struct netlink_ext_ack *extack)
616 static void xfrmi_netlink_parms(struct nlattr *data[],
617 struct xfrm_if_parms *parms)
619 memset(parms, 0, sizeof(*parms));
624 if (data[IFLA_XFRM_LINK])
625 parms->link = nla_get_u32(data[IFLA_XFRM_LINK]);
627 if (data[IFLA_XFRM_IF_ID])
628 parms->if_id = nla_get_u32(data[IFLA_XFRM_IF_ID]);
631 static int xfrmi_newlink(struct net *src_net, struct net_device *dev,
632 struct nlattr *tb[], struct nlattr *data[],
633 struct netlink_ext_ack *extack)
635 struct net *net = dev_net(dev);
636 struct xfrm_if_parms p;
640 xfrmi_netlink_parms(data, &p);
642 if (!tb[IFLA_IFNAME])
645 nla_strlcpy(p.name, tb[IFLA_IFNAME], IFNAMSIZ);
647 xi = xfrmi_locate(net, &p);
651 xi = netdev_priv(dev);
655 xi->phydev = dev_get_by_index(net, p.link);
659 err = xfrmi_create(dev);
665 static void xfrmi_dellink(struct net_device *dev, struct list_head *head)
667 unregister_netdevice_queue(dev, head);
670 static int xfrmi_changelink(struct net_device *dev, struct nlattr *tb[],
671 struct nlattr *data[],
672 struct netlink_ext_ack *extack)
674 struct xfrm_if *xi = netdev_priv(dev);
675 struct net *net = dev_net(dev);
677 xfrmi_netlink_parms(data, &xi->p);
679 xi = xfrmi_locate(net, &xi->p);
681 xi = netdev_priv(dev);
687 return xfrmi_update(xi, &xi->p);
690 static size_t xfrmi_get_size(const struct net_device *dev)
695 /* IFLA_XFRM_IF_ID */
700 static int xfrmi_fill_info(struct sk_buff *skb, const struct net_device *dev)
702 struct xfrm_if *xi = netdev_priv(dev);
703 struct xfrm_if_parms *parm = &xi->p;
705 if (nla_put_u32(skb, IFLA_XFRM_LINK, parm->link) ||
706 nla_put_u32(skb, IFLA_XFRM_IF_ID, parm->if_id))
707 goto nla_put_failure;
714 static struct net *xfrmi_get_link_net(const struct net_device *dev)
716 struct xfrm_if *xi = netdev_priv(dev);
718 return dev_net(xi->phydev);
721 static const struct nla_policy xfrmi_policy[IFLA_XFRM_MAX + 1] = {
722 [IFLA_XFRM_LINK] = { .type = NLA_U32 },
723 [IFLA_XFRM_IF_ID] = { .type = NLA_U32 },
726 static struct rtnl_link_ops xfrmi_link_ops __read_mostly = {
728 .maxtype = IFLA_XFRM_MAX,
729 .policy = xfrmi_policy,
730 .priv_size = sizeof(struct xfrm_if),
731 .setup = xfrmi_dev_setup,
732 .validate = xfrmi_validate,
733 .newlink = xfrmi_newlink,
734 .dellink = xfrmi_dellink,
735 .changelink = xfrmi_changelink,
736 .get_size = xfrmi_get_size,
737 .fill_info = xfrmi_fill_info,
738 .get_link_net = xfrmi_get_link_net,
741 static void __net_exit xfrmi_destroy_interfaces(struct xfrmi_net *xfrmn)
746 xi = rtnl_dereference(xfrmn->xfrmi[0]);
750 unregister_netdevice_queue(xi->dev, &list);
751 unregister_netdevice_many(&list);
754 static void __net_exit xfrmi_exit_net(struct net *net)
756 struct xfrmi_net *xfrmn = net_generic(net, xfrmi_net_id);
759 xfrmi_destroy_interfaces(xfrmn);
763 static struct pernet_operations xfrmi_net_ops = {
764 .exit = xfrmi_exit_net,
766 .size = sizeof(struct xfrmi_net),
769 static struct xfrm6_protocol xfrmi_esp6_protocol __read_mostly = {
770 .handler = xfrm6_rcv,
771 .cb_handler = xfrmi_rcv_cb,
772 .err_handler = xfrmi6_err,
776 static struct xfrm6_protocol xfrmi_ah6_protocol __read_mostly = {
777 .handler = xfrm6_rcv,
778 .cb_handler = xfrmi_rcv_cb,
779 .err_handler = xfrmi6_err,
783 static struct xfrm6_protocol xfrmi_ipcomp6_protocol __read_mostly = {
784 .handler = xfrm6_rcv,
785 .cb_handler = xfrmi_rcv_cb,
786 .err_handler = xfrmi6_err,
790 static struct xfrm4_protocol xfrmi_esp4_protocol __read_mostly = {
791 .handler = xfrm4_rcv,
792 .input_handler = xfrm_input,
793 .cb_handler = xfrmi_rcv_cb,
794 .err_handler = xfrmi4_err,
798 static struct xfrm4_protocol xfrmi_ah4_protocol __read_mostly = {
799 .handler = xfrm4_rcv,
800 .input_handler = xfrm_input,
801 .cb_handler = xfrmi_rcv_cb,
802 .err_handler = xfrmi4_err,
806 static struct xfrm4_protocol xfrmi_ipcomp4_protocol __read_mostly = {
807 .handler = xfrm4_rcv,
808 .input_handler = xfrm_input,
809 .cb_handler = xfrmi_rcv_cb,
810 .err_handler = xfrmi4_err,
814 static int __init xfrmi4_init(void)
818 err = xfrm4_protocol_register(&xfrmi_esp4_protocol, IPPROTO_ESP);
820 goto xfrm_proto_esp_failed;
821 err = xfrm4_protocol_register(&xfrmi_ah4_protocol, IPPROTO_AH);
823 goto xfrm_proto_ah_failed;
824 err = xfrm4_protocol_register(&xfrmi_ipcomp4_protocol, IPPROTO_COMP);
826 goto xfrm_proto_comp_failed;
830 xfrm_proto_comp_failed:
831 xfrm4_protocol_deregister(&xfrmi_ah4_protocol, IPPROTO_AH);
832 xfrm_proto_ah_failed:
833 xfrm4_protocol_deregister(&xfrmi_esp4_protocol, IPPROTO_ESP);
834 xfrm_proto_esp_failed:
838 static void xfrmi4_fini(void)
840 xfrm4_protocol_deregister(&xfrmi_ipcomp4_protocol, IPPROTO_COMP);
841 xfrm4_protocol_deregister(&xfrmi_ah4_protocol, IPPROTO_AH);
842 xfrm4_protocol_deregister(&xfrmi_esp4_protocol, IPPROTO_ESP);
845 static int __init xfrmi6_init(void)
849 err = xfrm6_protocol_register(&xfrmi_esp6_protocol, IPPROTO_ESP);
851 goto xfrm_proto_esp_failed;
852 err = xfrm6_protocol_register(&xfrmi_ah6_protocol, IPPROTO_AH);
854 goto xfrm_proto_ah_failed;
855 err = xfrm6_protocol_register(&xfrmi_ipcomp6_protocol, IPPROTO_COMP);
857 goto xfrm_proto_comp_failed;
861 xfrm_proto_comp_failed:
862 xfrm6_protocol_deregister(&xfrmi_ah6_protocol, IPPROTO_AH);
863 xfrm_proto_ah_failed:
864 xfrm6_protocol_deregister(&xfrmi_esp6_protocol, IPPROTO_ESP);
865 xfrm_proto_esp_failed:
869 static void xfrmi6_fini(void)
871 xfrm6_protocol_deregister(&xfrmi_ipcomp6_protocol, IPPROTO_COMP);
872 xfrm6_protocol_deregister(&xfrmi_ah6_protocol, IPPROTO_AH);
873 xfrm6_protocol_deregister(&xfrmi_esp6_protocol, IPPROTO_ESP);
876 static const struct xfrm_if_cb xfrm_if_cb = {
877 .decode_session = xfrmi_decode_session,
880 static int __init xfrmi_init(void)
885 pr_info("IPsec XFRM device driver\n");
887 msg = "tunnel device";
888 err = register_pernet_device(&xfrmi_net_ops);
890 goto pernet_dev_failed;
892 msg = "xfrm4 protocols";
897 msg = "xfrm6 protocols";
903 msg = "netlink interface";
904 err = rtnl_link_register(&xfrmi_link_ops);
906 goto rtnl_link_failed;
908 xfrm_if_register_cb(&xfrm_if_cb);
917 unregister_pernet_device(&xfrmi_net_ops);
919 pr_err("xfrmi init: failed to register %s\n", msg);
923 static void __exit xfrmi_fini(void)
925 xfrm_if_unregister_cb();
926 rtnl_link_unregister(&xfrmi_link_ops);
929 unregister_pernet_device(&xfrmi_net_ops);
932 module_init(xfrmi_init);
933 module_exit(xfrmi_fini);
934 MODULE_LICENSE("GPL");
935 MODULE_ALIAS_RTNL_LINK("xfrm");
936 MODULE_ALIAS_NETDEV("xfrm0");
937 MODULE_AUTHOR("Steffen Klassert");
938 MODULE_DESCRIPTION("XFRM virtual interface");