1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * XFRM virtual interface
4 *
5 * Copyright (C) 2018 secunet Security Networks AG
6 *
7 * Author:
8 * Steffen Klassert <steffen.klassert@secunet.com>
9 */
10
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>
17 #include <linux/if.h>
18 #include <linux/in.h>
19 #include <linux/ip.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>
32
33 #include <linux/uaccess.h>
34 #include <linux/atomic.h>
35
36 #include <net/gso.h>
37 #include <net/icmp.h>
38 #include <net/ip.h>
39 #include <net/ipv6.h>
40 #include <net/ip6_route.h>
41 #include <net/ip_tunnels.h>
42 #include <net/addrconf.h>
43 #include <net/xfrm.h>
44 #include <net/net_namespace.h>
45 #include <net/dst_metadata.h>
46 #include <net/netns/generic.h>
47 #include <linux/etherdevice.h>
48
49 static int xfrmi_dev_init(struct net_device *dev);
50 static void xfrmi_dev_setup(struct net_device *dev);
51 static struct rtnl_link_ops xfrmi_link_ops __read_mostly;
52 static unsigned int xfrmi_net_id __read_mostly;
53 static const struct net_device_ops xfrmi_netdev_ops;
54
55 #define XFRMI_HASH_BITS 8
56 #define XFRMI_HASH_SIZE BIT(XFRMI_HASH_BITS)
57
58 struct xfrmi_net {
59 /* lists for storing interfaces in use */
60 struct xfrm_if __rcu *xfrmi[XFRMI_HASH_SIZE];
61 struct xfrm_if __rcu *collect_md_xfrmi;
62 };
63
64 static const struct nla_policy xfrm_lwt_policy[LWT_XFRM_MAX + 1] = {
65 [LWT_XFRM_IF_ID] = NLA_POLICY_MIN(NLA_U32, 1),
66 [LWT_XFRM_LINK] = NLA_POLICY_MIN(NLA_U32, 1),
67 };
68
69 static void xfrmi_destroy_state(struct lwtunnel_state *lwt)
70 {
71 }
72
73 static int xfrmi_build_state(struct net *net, struct nlattr *nla,
74 unsigned int family, const void *cfg,
75 struct lwtunnel_state **ts,
76 struct netlink_ext_ack *extack)
77 {
78 struct nlattr *tb[LWT_XFRM_MAX + 1];
79 struct lwtunnel_state *new_state;
80 struct xfrm_md_info *info;
81 int ret;
82
83 ret = nla_parse_nested(tb, LWT_XFRM_MAX, nla, xfrm_lwt_policy, extack);
84 if (ret < 0)
85 return ret;
86
87 if (!tb[LWT_XFRM_IF_ID]) {
88 NL_SET_ERR_MSG(extack, "if_id must be set");
89 return -EINVAL;
90 }
91
92 new_state = lwtunnel_state_alloc(sizeof(*info));
93 if (!new_state) {
94 NL_SET_ERR_MSG(extack, "failed to create encap info");
95 return -ENOMEM;
96 }
97
98 new_state->type = LWTUNNEL_ENCAP_XFRM;
99
100 info = lwt_xfrm_info(new_state);
101
102 info->if_id = nla_get_u32(tb[LWT_XFRM_IF_ID]);
103
104 if (tb[LWT_XFRM_LINK])
105 info->link = nla_get_u32(tb[LWT_XFRM_LINK]);
106
107 *ts = new_state;
108 return 0;
109 }
110
111 static int xfrmi_fill_encap_info(struct sk_buff *skb,
112 struct lwtunnel_state *lwt)
113 {
114 struct xfrm_md_info *info = lwt_xfrm_info(lwt);
115
116 if (nla_put_u32(skb, LWT_XFRM_IF_ID, info->if_id) ||
117 (info->link && nla_put_u32(skb, LWT_XFRM_LINK, info->link)))
118 return -EMSGSIZE;
119
120 return 0;
121 }
122
123 static int xfrmi_encap_nlsize(struct lwtunnel_state *lwtstate)
124 {
125 return nla_total_size(sizeof(u32)) + /* LWT_XFRM_IF_ID */
126 nla_total_size(sizeof(u32)); /* LWT_XFRM_LINK */
127 }
128
129 static int xfrmi_encap_cmp(struct lwtunnel_state *a, struct lwtunnel_state *b)
130 {
131 struct xfrm_md_info *a_info = lwt_xfrm_info(a);
132 struct xfrm_md_info *b_info = lwt_xfrm_info(b);
133
134 return memcmp(a_info, b_info, sizeof(*a_info));
135 }
136
137 static const struct lwtunnel_encap_ops xfrmi_encap_ops = {
138 .build_state = xfrmi_build_state,
139 .destroy_state = xfrmi_destroy_state,
140 .fill_encap = xfrmi_fill_encap_info,
141 .get_encap_size = xfrmi_encap_nlsize,
142 .cmp_encap = xfrmi_encap_cmp,
143 .owner = THIS_MODULE,
144 };
145
146 #define for_each_xfrmi_rcu(start, xi) \
147 for (xi = rcu_dereference(start); xi; xi = rcu_dereference(xi->next))
148
149 static u32 xfrmi_hash(u32 if_id)
150 {
151 return hash_32(if_id, XFRMI_HASH_BITS);
152 }
153
154 static struct xfrm_if *xfrmi_lookup(struct net *net, struct xfrm_state *x)
155 {
156 struct xfrmi_net *xfrmn = net_generic(net, xfrmi_net_id);
157 struct xfrm_if *xi;
158
159 for_each_xfrmi_rcu(xfrmn->xfrmi[xfrmi_hash(x->if_id)], xi) {
160 if (x->if_id == xi->p.if_id &&
161 (xi->dev->flags & IFF_UP))
162 return xi;
163 }
164
165 xi = rcu_dereference(xfrmn->collect_md_xfrmi);
166 if (xi && (xi->dev->flags & IFF_UP))
167 return xi;
168
169 return NULL;
170 }
171
172 static bool xfrmi_decode_session(struct sk_buff *skb,
173 unsigned short family,
174 struct xfrm_if_decode_session_result *res)
175 {
176 struct net_device *dev;
177 struct xfrm_if *xi;
178 int ifindex = 0;
179
180 if (!secpath_exists(skb) || !skb->dev)
181 return false;
182
183 switch (family) {
184 case AF_INET6:
185 ifindex = inet6_sdif(skb);
186 break;
187 case AF_INET:
188 ifindex = inet_sdif(skb);
189 break;
190 }
191
192 if (ifindex) {
193 struct net *net = xs_net(xfrm_input_state(skb));
194
195 dev = dev_get_by_index_rcu(net, ifindex);
196 } else {
197 dev = skb->dev;
198 }
199
200 if (!dev || !(dev->flags & IFF_UP))
201 return false;
202 if (dev->netdev_ops != &xfrmi_netdev_ops)
203 return false;
204
205 xi = netdev_priv(dev);
206 res->net = xi->net;
207
208 if (xi->p.collect_md)
209 res->if_id = xfrm_input_state(skb)->if_id;
210 else
211 res->if_id = xi->p.if_id;
212 return true;
213 }
214
215 static void xfrmi_link(struct xfrmi_net *xfrmn, struct xfrm_if *xi)
216 {
217 struct xfrm_if __rcu **xip = &xfrmn->xfrmi[xfrmi_hash(xi->p.if_id)];
218
219 rcu_assign_pointer(xi->next , rtnl_dereference(*xip));
220 rcu_assign_pointer(*xip, xi);
221 }
222
223 static void xfrmi_unlink(struct xfrmi_net *xfrmn, struct xfrm_if *xi)
224 {
225 struct xfrm_if __rcu **xip;
226 struct xfrm_if *iter;
227
228 for (xip = &xfrmn->xfrmi[xfrmi_hash(xi->p.if_id)];
229 (iter = rtnl_dereference(*xip)) != NULL;
230 xip = &iter->next) {
231 if (xi == iter) {
232 rcu_assign_pointer(*xip, xi->next);
233 break;
234 }
235 }
236 }
237
238 static void xfrmi_dev_free(struct net_device *dev)
239 {
240 struct xfrm_if *xi = netdev_priv(dev);
241
242 gro_cells_destroy(&xi->gro_cells);
243 }
244
245 static int xfrmi_create(struct net_device *dev)
246 {
247 struct xfrm_if *xi = netdev_priv(dev);
248 struct net *net = dev_net(dev);
249 struct xfrmi_net *xfrmn = net_generic(net, xfrmi_net_id);
250 int err;
251
252 dev->rtnl_link_ops = &xfrmi_link_ops;
253 err = register_netdevice(dev);
254 if (err < 0)
255 goto out;
256
257 if (xi->p.collect_md)
258 rcu_assign_pointer(xfrmn->collect_md_xfrmi, xi);
259 else
260 xfrmi_link(xfrmn, xi);
261
262 return 0;
263
264 out:
265 return err;
266 }
267
268 static struct xfrm_if *xfrmi_locate(struct net *net, struct xfrm_if_parms *p)
269 {
270 struct xfrm_if __rcu **xip;
271 struct xfrm_if *xi;
272 struct xfrmi_net *xfrmn = net_generic(net, xfrmi_net_id);
273
274 for (xip = &xfrmn->xfrmi[xfrmi_hash(p->if_id)];
275 (xi = rtnl_dereference(*xip)) != NULL;
276 xip = &xi->next)
277 if (xi->p.if_id == p->if_id)
278 return xi;
279
280 return NULL;
281 }
282
283 static void xfrmi_dev_uninit(struct net_device *dev)
284 {
285 struct xfrm_if *xi = netdev_priv(dev);
286 struct xfrmi_net *xfrmn = net_generic(xi->net, xfrmi_net_id);
287
288 if (xi->p.collect_md)
289 RCU_INIT_POINTER(xfrmn->collect_md_xfrmi, NULL);
290 else
291 xfrmi_unlink(xfrmn, xi);
292 }
293
294 static void xfrmi_scrub_packet(struct sk_buff *skb, bool xnet)
295 {
296 skb_clear_tstamp(skb);
297 skb->pkt_type = PACKET_HOST;
298 skb->skb_iif = 0;
299 skb->ignore_df = 0;
300 skb_dst_drop(skb);
301 nf_reset_ct(skb);
302 nf_reset_trace(skb);
303
304 if (!xnet)
305 return;
306
307 ipvs_reset(skb);
308 secpath_reset(skb);
309 skb_orphan(skb);
310 skb->mark = 0;
311 }
312
313 static int xfrmi_input(struct sk_buff *skb, int nexthdr, __be32 spi,
314 int encap_type, unsigned short family)
315 {
316 struct sec_path *sp;
317
318 sp = skb_sec_path(skb);
319 if (sp && (sp->len || sp->olen) &&
320 !xfrm_policy_check(NULL, XFRM_POLICY_IN, skb, family))
321 goto discard;
322
323 XFRM_SPI_SKB_CB(skb)->family = family;
324 if (family == AF_INET) {
325 XFRM_SPI_SKB_CB(skb)->daddroff = offsetof(struct iphdr, daddr);
326 XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip4 = NULL;
327 } else {
328 XFRM_SPI_SKB_CB(skb)->daddroff = offsetof(struct ipv6hdr, daddr);
329 XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6 = NULL;
330 }
331
332 return xfrm_input(skb, nexthdr, spi, encap_type);
333 discard:
334 kfree_skb(skb);
335 return 0;
336 }
337
338 static int xfrmi4_rcv(struct sk_buff *skb)
339 {
340 return xfrmi_input(skb, ip_hdr(skb)->protocol, 0, 0, AF_INET);
341 }
342
343 static int xfrmi6_rcv(struct sk_buff *skb)
344 {
345 return xfrmi_input(skb, skb_network_header(skb)[IP6CB(skb)->nhoff],
346 0, 0, AF_INET6);
347 }
348
349 static int xfrmi4_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type)
350 {
351 return xfrmi_input(skb, nexthdr, spi, encap_type, AF_INET);
352 }
353
354 static int xfrmi6_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type)
355 {
356 return xfrmi_input(skb, nexthdr, spi, encap_type, AF_INET6);
357 }
358
359 static int xfrmi_rcv_cb(struct sk_buff *skb, int err)
360 {
361 const struct xfrm_mode *inner_mode;
362 struct net_device *dev;
363 struct xfrm_state *x;
364 struct xfrm_if *xi;
365 bool xnet;
366 int link;
367
368 if (err && !secpath_exists(skb))
369 return 0;
370
371 x = xfrm_input_state(skb);
372
373 xi = xfrmi_lookup(xs_net(x), x);
374 if (!xi)
375 return 1;
376
377 link = skb->dev->ifindex;
378 dev = xi->dev;
379 skb->dev = dev;
380
381 if (err) {
382 DEV_STATS_INC(dev, rx_errors);
383 DEV_STATS_INC(dev, rx_dropped);
384
385 return 0;
386 }
387
388 xnet = !net_eq(xi->net, dev_net(skb->dev));
389
390 if (xnet) {
391 inner_mode = &x->inner_mode;
392
393 if (x->sel.family == AF_UNSPEC) {
394 inner_mode = xfrm_ip2inner_mode(x, XFRM_MODE_SKB_CB(skb)->protocol);
395 if (inner_mode == NULL) {
396 XFRM_INC_STATS(dev_net(skb->dev),
397 LINUX_MIB_XFRMINSTATEMODEERROR);
398 return -EINVAL;
399 }
400 }
401
402 if (!xfrm_policy_check(NULL, XFRM_POLICY_IN, skb,
403 inner_mode->family))
404 return -EPERM;
405 }
406
407 xfrmi_scrub_packet(skb, xnet);
408 if (xi->p.collect_md) {
409 struct metadata_dst *md_dst;
410
411 md_dst = metadata_dst_alloc(0, METADATA_XFRM, GFP_ATOMIC);
412 if (!md_dst)
413 return -ENOMEM;
414
415 md_dst->u.xfrm_info.if_id = x->if_id;
416 md_dst->u.xfrm_info.link = link;
417 skb_dst_set(skb, (struct dst_entry *)md_dst);
418 }
419 dev_sw_netstats_rx_add(dev, skb->len);
420
421 return 0;
422 }
423
424 static int
425 xfrmi_xmit2(struct sk_buff *skb, struct net_device *dev, struct flowi *fl)
426 {
427 struct xfrm_if *xi = netdev_priv(dev);
428 struct dst_entry *dst = skb_dst(skb);
429 unsigned int length = skb->len;
430 struct net_device *tdev;
431 struct xfrm_state *x;
432 int err = -1;
433 u32 if_id;
434 int mtu;
435
436 if (xi->p.collect_md) {
437 struct xfrm_md_info *md_info = skb_xfrm_md_info(skb);
438
439 if (unlikely(!md_info))
440 return -EINVAL;
441
442 if_id = md_info->if_id;
443 fl->flowi_oif = md_info->link;
444 if (md_info->dst_orig) {
445 struct dst_entry *tmp_dst = dst;
446
447 dst = md_info->dst_orig;
448 skb_dst_set(skb, dst);
449 md_info->dst_orig = NULL;
450 dst_release(tmp_dst);
451 }
452 } else {
453 if_id = xi->p.if_id;
454 }
455
456 dst_hold(dst);
457 dst = xfrm_lookup_with_ifid(xi->net, dst, fl, NULL, 0, if_id);
458 if (IS_ERR(dst)) {
459 err = PTR_ERR(dst);
460 dst = NULL;
461 goto tx_err_link_failure;
462 }
463
464 x = dst->xfrm;
465 if (!x)
466 goto tx_err_link_failure;
467
468 if (x->if_id != if_id)
469 goto tx_err_link_failure;
470
471 tdev = dst->dev;
472
473 if (tdev == dev) {
474 DEV_STATS_INC(dev, collisions);
475 net_warn_ratelimited("%s: Local routing loop detected!\n",
476 dev->name);
477 goto tx_err_dst_release;
478 }
479
480 mtu = dst_mtu(dst);
481 if ((!skb_is_gso(skb) && skb->len > mtu) ||
482 (skb_is_gso(skb) && !skb_gso_validate_network_len(skb, mtu))) {
483 skb_dst_update_pmtu_no_confirm(skb, mtu);
484
485 if (skb->protocol == htons(ETH_P_IPV6)) {
486 if (mtu < IPV6_MIN_MTU)
487 mtu = IPV6_MIN_MTU;
488
489 if (skb->len > 1280)
490 icmpv6_ndo_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
491 else
492 goto xmit;
493 } else {
494 if (!(ip_hdr(skb)->frag_off & htons(IP_DF)))
495 goto xmit;
496 icmp_ndo_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
497 htonl(mtu));
498 }
499
500 dst_release(dst);
501 return -EMSGSIZE;
502 }
503
504 xmit:
505 xfrmi_scrub_packet(skb, !net_eq(xi->net, dev_net(dev)));
506 skb_dst_set(skb, dst);
507 skb->dev = tdev;
508
509 err = dst_output(xi->net, skb->sk, skb);
510 if (net_xmit_eval(err) == 0) {
511 dev_sw_netstats_tx_add(dev, 1, length);
512 } else {
513 DEV_STATS_INC(dev, tx_errors);
514 DEV_STATS_INC(dev, tx_aborted_errors);
515 }
516
517 return 0;
518 tx_err_link_failure:
519 DEV_STATS_INC(dev, tx_carrier_errors);
520 dst_link_failure(skb);
521 tx_err_dst_release:
522 dst_release(dst);
523 return err;
524 }
525
526 static netdev_tx_t xfrmi_xmit(struct sk_buff *skb, struct net_device *dev)
527 {
528 struct xfrm_if *xi = netdev_priv(dev);
529 struct dst_entry *dst = skb_dst(skb);
530 struct flowi fl;
531 int ret;
532
533 memset(&fl, 0, sizeof(fl));
534
535 switch (skb->protocol) {
536 case htons(ETH_P_IPV6):
537 memset(IP6CB(skb), 0, sizeof(*IP6CB(skb)));
538 xfrm_decode_session(dev_net(dev), skb, &fl, AF_INET6);
539 if (!dst) {
540 fl.u.ip6.flowi6_oif = dev->ifindex;
541 fl.u.ip6.flowi6_flags |= FLOWI_FLAG_ANYSRC;
542 dst = ip6_route_output(dev_net(dev), NULL, &fl.u.ip6);
543 if (dst->error) {
544 dst_release(dst);
545 DEV_STATS_INC(dev, tx_carrier_errors);
546 goto tx_err;
547 }
548 skb_dst_set(skb, dst);
549 }
550 break;
551 case htons(ETH_P_IP):
552 memset(IPCB(skb), 0, sizeof(*IPCB(skb)));
553 xfrm_decode_session(dev_net(dev), skb, &fl, AF_INET);
554 if (!dst) {
555 struct rtable *rt;
556
557 fl.u.ip4.flowi4_oif = dev->ifindex;
558 fl.u.ip4.flowi4_flags |= FLOWI_FLAG_ANYSRC;
559 rt = __ip_route_output_key(dev_net(dev), &fl.u.ip4);
560 if (IS_ERR(rt)) {
561 DEV_STATS_INC(dev, tx_carrier_errors);
562 goto tx_err;
563 }
564 skb_dst_set(skb, &rt->dst);
565 }
566 break;
567 default:
568 goto tx_err;
569 }
570
571 fl.flowi_oif = xi->p.link;
572
573 ret = xfrmi_xmit2(skb, dev, &fl);
574 if (ret < 0)
575 goto tx_err;
576
577 return NETDEV_TX_OK;
578
579 tx_err:
580 DEV_STATS_INC(dev, tx_errors);
581 DEV_STATS_INC(dev, tx_dropped);
582 kfree_skb(skb);
583 return NETDEV_TX_OK;
584 }
585
586 static int xfrmi4_err(struct sk_buff *skb, u32 info)
587 {
588 const struct iphdr *iph = (const struct iphdr *)skb->data;
589 struct net *net = dev_net(skb->dev);
590 int protocol = iph->protocol;
591 struct ip_comp_hdr *ipch;
592 struct ip_esp_hdr *esph;
593 struct ip_auth_hdr *ah ;
594 struct xfrm_state *x;
595 struct xfrm_if *xi;
596 __be32 spi;
597
598 switch (protocol) {
599 case IPPROTO_ESP:
600 esph = (struct ip_esp_hdr *)(skb->data+(iph->ihl<<2));
601 spi = esph->spi;
602 break;
603 case IPPROTO_AH:
604 ah = (struct ip_auth_hdr *)(skb->data+(iph->ihl<<2));
605 spi = ah->spi;
606 break;
607 case IPPROTO_COMP:
608 ipch = (struct ip_comp_hdr *)(skb->data+(iph->ihl<<2));
609 spi = htonl(ntohs(ipch->cpi));
610 break;
611 default:
612 return 0;
613 }
614
615 switch (icmp_hdr(skb)->type) {
616 case ICMP_DEST_UNREACH:
617 if (icmp_hdr(skb)->code != ICMP_FRAG_NEEDED)
618 return 0;
619 break;
620 case ICMP_REDIRECT:
621 break;
622 default:
623 return 0;
624 }
625
626 x = xfrm_state_lookup(net, skb->mark, (const xfrm_address_t *)&iph->daddr,
627 spi, protocol, AF_INET);
628 if (!x)
629 return 0;
630
631 xi = xfrmi_lookup(net, x);
632 if (!xi) {
633 xfrm_state_put(x);
634 return -1;
635 }
636
637 if (icmp_hdr(skb)->type == ICMP_DEST_UNREACH)
638 ipv4_update_pmtu(skb, net, info, 0, protocol);
639 else
640 ipv4_redirect(skb, net, 0, protocol);
641 xfrm_state_put(x);
642
643 return 0;
644 }
645
646 static int xfrmi6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
647 u8 type, u8 code, int offset, __be32 info)
648 {
649 const struct ipv6hdr *iph = (const struct ipv6hdr *)skb->data;
650 struct net *net = dev_net(skb->dev);
651 int protocol = iph->nexthdr;
652 struct ip_comp_hdr *ipch;
653 struct ip_esp_hdr *esph;
654 struct ip_auth_hdr *ah;
655 struct xfrm_state *x;
656 struct xfrm_if *xi;
657 __be32 spi;
658
659 switch (protocol) {
660 case IPPROTO_ESP:
661 esph = (struct ip_esp_hdr *)(skb->data + offset);
662 spi = esph->spi;
663 break;
664 case IPPROTO_AH:
665 ah = (struct ip_auth_hdr *)(skb->data + offset);
666 spi = ah->spi;
667 break;
668 case IPPROTO_COMP:
669 ipch = (struct ip_comp_hdr *)(skb->data + offset);
670 spi = htonl(ntohs(ipch->cpi));
671 break;
672 default:
673 return 0;
674 }
675
676 if (type != ICMPV6_PKT_TOOBIG &&
677 type != NDISC_REDIRECT)
678 return 0;
679
680 x = xfrm_state_lookup(net, skb->mark, (const xfrm_address_t *)&iph->daddr,
681 spi, protocol, AF_INET6);
682 if (!x)
683 return 0;
684
685 xi = xfrmi_lookup(net, x);
686 if (!xi) {
687 xfrm_state_put(x);
688 return -1;
689 }
690
691 if (type == NDISC_REDIRECT)
692 ip6_redirect(skb, net, skb->dev->ifindex, 0,
693 sock_net_uid(net, NULL));
694 else
695 ip6_update_pmtu(skb, net, info, 0, 0, sock_net_uid(net, NULL));
696 xfrm_state_put(x);
697
698 return 0;
699 }
700
701 static int xfrmi_change(struct xfrm_if *xi, const struct xfrm_if_parms *p)
702 {
703 if (xi->p.link != p->link)
704 return -EINVAL;
705
706 xi->p.if_id = p->if_id;
707
708 return 0;
709 }
710
711 static int xfrmi_update(struct xfrm_if *xi, struct xfrm_if_parms *p)
712 {
713 struct net *net = xi->net;
714 struct xfrmi_net *xfrmn = net_generic(net, xfrmi_net_id);
715 int err;
716
717 xfrmi_unlink(xfrmn, xi);
718 synchronize_net();
719 err = xfrmi_change(xi, p);
720 xfrmi_link(xfrmn, xi);
721 netdev_state_change(xi->dev);
722 return err;
723 }
724
725 static int xfrmi_get_iflink(const struct net_device *dev)
726 {
727 struct xfrm_if *xi = netdev_priv(dev);
728
729 return READ_ONCE(xi->p.link);
730 }
731
732 static const struct net_device_ops xfrmi_netdev_ops = {
733 .ndo_init = xfrmi_dev_init,
734 .ndo_uninit = xfrmi_dev_uninit,
735 .ndo_start_xmit = xfrmi_xmit,
736 .ndo_get_stats64 = dev_get_tstats64,
737 .ndo_get_iflink = xfrmi_get_iflink,
738 };
739
740 static void xfrmi_dev_setup(struct net_device *dev)
741 {
742 dev->netdev_ops = &xfrmi_netdev_ops;
743 dev->header_ops = &ip_tunnel_header_ops;
744 dev->type = ARPHRD_NONE;
745 dev->mtu = ETH_DATA_LEN;
746 dev->min_mtu = ETH_MIN_MTU;
747 dev->max_mtu = IP_MAX_MTU;
748 dev->flags = IFF_NOARP;
749 dev->needs_free_netdev = true;
750 dev->priv_destructor = xfrmi_dev_free;
751 dev->pcpu_stat_type = NETDEV_PCPU_STAT_TSTATS;
752 netif_keep_dst(dev);
753
754 eth_broadcast_addr(dev->broadcast);
755 }
756
757 #define XFRMI_FEATURES (NETIF_F_SG | \
758 NETIF_F_FRAGLIST | \
759 NETIF_F_GSO_SOFTWARE | \
760 NETIF_F_HW_CSUM)
761
762 static int xfrmi_dev_init(struct net_device *dev)
763 {
764 struct xfrm_if *xi = netdev_priv(dev);
765 struct net_device *phydev = __dev_get_by_index(xi->net, xi->p.link);
766 int err;
767
768 err = gro_cells_init(&xi->gro_cells, dev);
769 if (err)
770 return err;
771
772 dev->features |= NETIF_F_LLTX;
773 dev->features |= XFRMI_FEATURES;
774 dev->hw_features |= XFRMI_FEATURES;
775
776 if (phydev) {
777 dev->needed_headroom = phydev->needed_headroom;
778 dev->needed_tailroom = phydev->needed_tailroom;
779
780 if (is_zero_ether_addr(dev->dev_addr))
781 eth_hw_addr_inherit(dev, phydev);
782 if (is_zero_ether_addr(dev->broadcast))
783 memcpy(dev->broadcast, phydev->broadcast,
784 dev->addr_len);
785 } else {
786 eth_hw_addr_random(dev);
787 eth_broadcast_addr(dev->broadcast);
788 }
789
790 return 0;
791 }
792
793 static int xfrmi_validate(struct nlattr *tb[], struct nlattr *data[],
794 struct netlink_ext_ack *extack)
795 {
796 return 0;
797 }
798
799 static void xfrmi_netlink_parms(struct nlattr *data[],
800 struct xfrm_if_parms *parms)
801 {
802 memset(parms, 0, sizeof(*parms));
803
804 if (!data)
805 return;
806
807 if (data[IFLA_XFRM_LINK])
808 parms->link = nla_get_u32(data[IFLA_XFRM_LINK]);
809
810 if (data[IFLA_XFRM_IF_ID])
811 parms->if_id = nla_get_u32(data[IFLA_XFRM_IF_ID]);
812
813 if (data[IFLA_XFRM_COLLECT_METADATA])
814 parms->collect_md = true;
815 }
816
817 static int xfrmi_newlink(struct net *src_net, struct net_device *dev,
818 struct nlattr *tb[], struct nlattr *data[],
819 struct netlink_ext_ack *extack)
820 {
821 struct net *net = dev_net(dev);
822 struct xfrm_if_parms p = {};
823 struct xfrm_if *xi;
824 int err;
825
826 xfrmi_netlink_parms(data, &p);
827 if (p.collect_md) {
828 struct xfrmi_net *xfrmn = net_generic(net, xfrmi_net_id);
829
830 if (p.link || p.if_id) {
831 NL_SET_ERR_MSG(extack, "link and if_id must be zero");
832 return -EINVAL;
833 }
834
835 if (rtnl_dereference(xfrmn->collect_md_xfrmi))
836 return -EEXIST;
837
838 } else {
839 if (!p.if_id) {
840 NL_SET_ERR_MSG(extack, "if_id must be non zero");
841 return -EINVAL;
842 }
843
844 xi = xfrmi_locate(net, &p);
845 if (xi)
846 return -EEXIST;
847 }
848
849 xi = netdev_priv(dev);
850 xi->p = p;
851 xi->net = net;
852 xi->dev = dev;
853
854 err = xfrmi_create(dev);
855 return err;
856 }
857
858 static void xfrmi_dellink(struct net_device *dev, struct list_head *head)
859 {
860 unregister_netdevice_queue(dev, head);
861 }
862
863 static int xfrmi_changelink(struct net_device *dev, struct nlattr *tb[],
864 struct nlattr *data[],
865 struct netlink_ext_ack *extack)
866 {
867 struct xfrm_if *xi = netdev_priv(dev);
868 struct net *net = xi->net;
869 struct xfrm_if_parms p = {};
870
871 xfrmi_netlink_parms(data, &p);
872 if (!p.if_id) {
873 NL_SET_ERR_MSG(extack, "if_id must be non zero");
874 return -EINVAL;
875 }
876
877 if (p.collect_md) {
878 NL_SET_ERR_MSG(extack, "collect_md can't be changed");
879 return -EINVAL;
880 }
881
882 xi = xfrmi_locate(net, &p);
883 if (!xi) {
884 xi = netdev_priv(dev);
885 } else {
886 if (xi->dev != dev)
887 return -EEXIST;
888 if (xi->p.collect_md) {
889 NL_SET_ERR_MSG(extack,
890 "device can't be changed to collect_md");
891 return -EINVAL;
892 }
893 }
894
895 return xfrmi_update(xi, &p);
896 }
897
898 static size_t xfrmi_get_size(const struct net_device *dev)
899 {
900 return
901 /* IFLA_XFRM_LINK */
902 nla_total_size(4) +
903 /* IFLA_XFRM_IF_ID */
904 nla_total_size(4) +
905 /* IFLA_XFRM_COLLECT_METADATA */
906 nla_total_size(0) +
907 0;
908 }
909
910 static int xfrmi_fill_info(struct sk_buff *skb, const struct net_device *dev)
911 {
912 struct xfrm_if *xi = netdev_priv(dev);
913 struct xfrm_if_parms *parm = &xi->p;
914
915 if (nla_put_u32(skb, IFLA_XFRM_LINK, parm->link) ||
916 nla_put_u32(skb, IFLA_XFRM_IF_ID, parm->if_id) ||
917 (xi->p.collect_md && nla_put_flag(skb, IFLA_XFRM_COLLECT_METADATA)))
918 goto nla_put_failure;
919 return 0;
920
921 nla_put_failure:
922 return -EMSGSIZE;
923 }
924
925 static struct net *xfrmi_get_link_net(const struct net_device *dev)
926 {
927 struct xfrm_if *xi = netdev_priv(dev);
928
929 return READ_ONCE(xi->net);
930 }
931
932 static const struct nla_policy xfrmi_policy[IFLA_XFRM_MAX + 1] = {
933 [IFLA_XFRM_UNSPEC] = { .strict_start_type = IFLA_XFRM_COLLECT_METADATA },
934 [IFLA_XFRM_LINK] = { .type = NLA_U32 },
935 [IFLA_XFRM_IF_ID] = { .type = NLA_U32 },
936 [IFLA_XFRM_COLLECT_METADATA] = { .type = NLA_FLAG },
937 };
938
939 static struct rtnl_link_ops xfrmi_link_ops __read_mostly = {
940 .kind = "xfrm",
941 .maxtype = IFLA_XFRM_MAX,
942 .policy = xfrmi_policy,
943 .priv_size = sizeof(struct xfrm_if),
944 .setup = xfrmi_dev_setup,
945 .validate = xfrmi_validate,
946 .newlink = xfrmi_newlink,
947 .dellink = xfrmi_dellink,
948 .changelink = xfrmi_changelink,
949 .get_size = xfrmi_get_size,
950 .fill_info = xfrmi_fill_info,
951 .get_link_net = xfrmi_get_link_net,
952 };
953
954 static void __net_exit xfrmi_exit_batch_rtnl(struct list_head *net_exit_list,
955 struct list_head *dev_to_kill)
956 {
957 struct net *net;
958
959 ASSERT_RTNL();
960 list_for_each_entry(net, net_exit_list, exit_list) {
961 struct xfrmi_net *xfrmn = net_generic(net, xfrmi_net_id);
962 struct xfrm_if __rcu **xip;
963 struct xfrm_if *xi;
964 int i;
965
966 for (i = 0; i < XFRMI_HASH_SIZE; i++) {
967 for (xip = &xfrmn->xfrmi[i];
968 (xi = rtnl_dereference(*xip)) != NULL;
969 xip = &xi->next)
970 unregister_netdevice_queue(xi->dev, dev_to_kill);
971 }
972 xi = rtnl_dereference(xfrmn->collect_md_xfrmi);
973 if (xi)
974 unregister_netdevice_queue(xi->dev, dev_to_kill);
975 }
976 }
977
978 static struct pernet_operations xfrmi_net_ops = {
979 .exit_batch_rtnl = xfrmi_exit_batch_rtnl,
980 .id = &xfrmi_net_id,
981 .size = sizeof(struct xfrmi_net),
982 };
983
984 static struct xfrm6_protocol xfrmi_esp6_protocol __read_mostly = {
985 .handler = xfrmi6_rcv,
986 .input_handler = xfrmi6_input,
987 .cb_handler = xfrmi_rcv_cb,
988 .err_handler = xfrmi6_err,
989 .priority = 10,
990 };
991
992 static struct xfrm6_protocol xfrmi_ah6_protocol __read_mostly = {
993 .handler = xfrm6_rcv,
994 .input_handler = xfrm_input,
995 .cb_handler = xfrmi_rcv_cb,
996 .err_handler = xfrmi6_err,
997 .priority = 10,
998 };
999
1000 static struct xfrm6_protocol xfrmi_ipcomp6_protocol __read_mostly = {
1001 .handler = xfrm6_rcv,
1002 .input_handler = xfrm_input,
1003 .cb_handler = xfrmi_rcv_cb,
1004 .err_handler = xfrmi6_err,
1005 .priority = 10,
1006 };
1007
1008 #if IS_REACHABLE(CONFIG_INET6_XFRM_TUNNEL)
1009 static int xfrmi6_rcv_tunnel(struct sk_buff *skb)
1010 {
1011 const xfrm_address_t *saddr;
1012 __be32 spi;
1013
1014 saddr = (const xfrm_address_t *)&ipv6_hdr(skb)->saddr;
1015 spi = xfrm6_tunnel_spi_lookup(dev_net(skb->dev), saddr);
1016
1017 return xfrm6_rcv_spi(skb, IPPROTO_IPV6, spi, NULL);
1018 }
1019
1020 static struct xfrm6_tunnel xfrmi_ipv6_handler __read_mostly = {
1021 .handler = xfrmi6_rcv_tunnel,
1022 .cb_handler = xfrmi_rcv_cb,
1023 .err_handler = xfrmi6_err,
1024 .priority = 2,
1025 };
1026
1027 static struct xfrm6_tunnel xfrmi_ip6ip_handler __read_mostly = {
1028 .handler = xfrmi6_rcv_tunnel,
1029 .cb_handler = xfrmi_rcv_cb,
1030 .err_handler = xfrmi6_err,
1031 .priority = 2,
1032 };
1033 #endif
1034
1035 static struct xfrm4_protocol xfrmi_esp4_protocol __read_mostly = {
1036 .handler = xfrmi4_rcv,
1037 .input_handler = xfrmi4_input,
1038 .cb_handler = xfrmi_rcv_cb,
1039 .err_handler = xfrmi4_err,
1040 .priority = 10,
1041 };
1042
1043 static struct xfrm4_protocol xfrmi_ah4_protocol __read_mostly = {
1044 .handler = xfrm4_rcv,
1045 .input_handler = xfrm_input,
1046 .cb_handler = xfrmi_rcv_cb,
1047 .err_handler = xfrmi4_err,
1048 .priority = 10,
1049 };
1050
1051 static struct xfrm4_protocol xfrmi_ipcomp4_protocol __read_mostly = {
1052 .handler = xfrm4_rcv,
1053 .input_handler = xfrm_input,
1054 .cb_handler = xfrmi_rcv_cb,
1055 .err_handler = xfrmi4_err,
1056 .priority = 10,
1057 };
1058
1059 #if IS_REACHABLE(CONFIG_INET_XFRM_TUNNEL)
1060 static int xfrmi4_rcv_tunnel(struct sk_buff *skb)
1061 {
1062 return xfrm4_rcv_spi(skb, IPPROTO_IPIP, ip_hdr(skb)->saddr);
1063 }
1064
1065 static struct xfrm_tunnel xfrmi_ipip_handler __read_mostly = {
1066 .handler = xfrmi4_rcv_tunnel,
1067 .cb_handler = xfrmi_rcv_cb,
1068 .err_handler = xfrmi4_err,
1069 .priority = 3,
1070 };
1071
1072 static struct xfrm_tunnel xfrmi_ipip6_handler __read_mostly = {
1073 .handler = xfrmi4_rcv_tunnel,
1074 .cb_handler = xfrmi_rcv_cb,
1075 .err_handler = xfrmi4_err,
1076 .priority = 2,
1077 };
1078 #endif
1079
1080 static int __init xfrmi4_init(void)
1081 {
1082 int err;
1083
1084 err = xfrm4_protocol_register(&xfrmi_esp4_protocol, IPPROTO_ESP);
1085 if (err < 0)
1086 goto xfrm_proto_esp_failed;
1087 err = xfrm4_protocol_register(&xfrmi_ah4_protocol, IPPROTO_AH);
1088 if (err < 0)
1089 goto xfrm_proto_ah_failed;
1090 err = xfrm4_protocol_register(&xfrmi_ipcomp4_protocol, IPPROTO_COMP);
1091 if (err < 0)
1092 goto xfrm_proto_comp_failed;
1093 #if IS_REACHABLE(CONFIG_INET_XFRM_TUNNEL)
1094 err = xfrm4_tunnel_register(&xfrmi_ipip_handler, AF_INET);
1095 if (err < 0)
1096 goto xfrm_tunnel_ipip_failed;
1097 err = xfrm4_tunnel_register(&xfrmi_ipip6_handler, AF_INET6);
1098 if (err < 0)
1099 goto xfrm_tunnel_ipip6_failed;
1100 #endif
1101
1102 return 0;
1103
1104 #if IS_REACHABLE(CONFIG_INET_XFRM_TUNNEL)
1105 xfrm_tunnel_ipip6_failed:
1106 xfrm4_tunnel_deregister(&xfrmi_ipip_handler, AF_INET);
1107 xfrm_tunnel_ipip_failed:
1108 xfrm4_protocol_deregister(&xfrmi_ipcomp4_protocol, IPPROTO_COMP);
1109 #endif
1110 xfrm_proto_comp_failed:
1111 xfrm4_protocol_deregister(&xfrmi_ah4_protocol, IPPROTO_AH);
1112 xfrm_proto_ah_failed:
1113 xfrm4_protocol_deregister(&xfrmi_esp4_protocol, IPPROTO_ESP);
1114 xfrm_proto_esp_failed:
1115 return err;
1116 }
1117
1118 static void xfrmi4_fini(void)
1119 {
1120 #if IS_REACHABLE(CONFIG_INET_XFRM_TUNNEL)
1121 xfrm4_tunnel_deregister(&xfrmi_ipip6_handler, AF_INET6);
1122 xfrm4_tunnel_deregister(&xfrmi_ipip_handler, AF_INET);
1123 #endif
1124 xfrm4_protocol_deregister(&xfrmi_ipcomp4_protocol, IPPROTO_COMP);
1125 xfrm4_protocol_deregister(&xfrmi_ah4_protocol, IPPROTO_AH);
1126 xfrm4_protocol_deregister(&xfrmi_esp4_protocol, IPPROTO_ESP);
1127 }
1128
1129 static int __init xfrmi6_init(void)
1130 {
1131 int err;
1132
1133 err = xfrm6_protocol_register(&xfrmi_esp6_protocol, IPPROTO_ESP);
1134 if (err < 0)
1135 goto xfrm_proto_esp_failed;
1136 err = xfrm6_protocol_register(&xfrmi_ah6_protocol, IPPROTO_AH);
1137 if (err < 0)
1138 goto xfrm_proto_ah_failed;
1139 err = xfrm6_protocol_register(&xfrmi_ipcomp6_protocol, IPPROTO_COMP);
1140 if (err < 0)
1141 goto xfrm_proto_comp_failed;
1142 #if IS_REACHABLE(CONFIG_INET6_XFRM_TUNNEL)
1143 err = xfrm6_tunnel_register(&xfrmi_ipv6_handler, AF_INET6);
1144 if (err < 0)
1145 goto xfrm_tunnel_ipv6_failed;
1146 err = xfrm6_tunnel_register(&xfrmi_ip6ip_handler, AF_INET);
1147 if (err < 0)
1148 goto xfrm_tunnel_ip6ip_failed;
1149 #endif
1150
1151 return 0;
1152
1153 #if IS_REACHABLE(CONFIG_INET6_XFRM_TUNNEL)
1154 xfrm_tunnel_ip6ip_failed:
1155 xfrm6_tunnel_deregister(&xfrmi_ipv6_handler, AF_INET6);
1156 xfrm_tunnel_ipv6_failed:
1157 xfrm6_protocol_deregister(&xfrmi_ipcomp6_protocol, IPPROTO_COMP);
1158 #endif
1159 xfrm_proto_comp_failed:
1160 xfrm6_protocol_deregister(&xfrmi_ah6_protocol, IPPROTO_AH);
1161 xfrm_proto_ah_failed:
1162 xfrm6_protocol_deregister(&xfrmi_esp6_protocol, IPPROTO_ESP);
1163 xfrm_proto_esp_failed:
1164 return err;
1165 }
1166
1167 static void xfrmi6_fini(void)
1168 {
1169 #if IS_REACHABLE(CONFIG_INET6_XFRM_TUNNEL)
1170 xfrm6_tunnel_deregister(&xfrmi_ip6ip_handler, AF_INET);
1171 xfrm6_tunnel_deregister(&xfrmi_ipv6_handler, AF_INET6);
1172 #endif
1173 xfrm6_protocol_deregister(&xfrmi_ipcomp6_protocol, IPPROTO_COMP);
1174 xfrm6_protocol_deregister(&xfrmi_ah6_protocol, IPPROTO_AH);
1175 xfrm6_protocol_deregister(&xfrmi_esp6_protocol, IPPROTO_ESP);
1176 }
1177
1178 static const struct xfrm_if_cb xfrm_if_cb = {
1179 .decode_session = xfrmi_decode_session,
1180 };
1181
1182 static int __init xfrmi_init(void)
1183 {
1184 const char *msg;
1185 int err;
1186
1187 pr_info("IPsec XFRM device driver\n");
1188
1189 msg = "tunnel device";
1190 err = register_pernet_device(&xfrmi_net_ops);
1191 if (err < 0)
1192 goto pernet_dev_failed;
1193
1194 msg = "xfrm4 protocols";
1195 err = xfrmi4_init();
1196 if (err < 0)
1197 goto xfrmi4_failed;
1198
1199 msg = "xfrm6 protocols";
1200 err = xfrmi6_init();
1201 if (err < 0)
1202 goto xfrmi6_failed;
1203
1204
1205 msg = "netlink interface";
1206 err = rtnl_link_register(&xfrmi_link_ops);
1207 if (err < 0)
1208 goto rtnl_link_failed;
1209
1210 err = register_xfrm_interface_bpf();
1211 if (err < 0)
1212 goto kfunc_failed;
1213
1214 lwtunnel_encap_add_ops(&xfrmi_encap_ops, LWTUNNEL_ENCAP_XFRM);
1215
1216 xfrm_if_register_cb(&xfrm_if_cb);
1217
1218 return err;
1219
1220 kfunc_failed:
1221 rtnl_link_unregister(&xfrmi_link_ops);
1222 rtnl_link_failed:
1223 xfrmi6_fini();
1224 xfrmi6_failed:
1225 xfrmi4_fini();
1226 xfrmi4_failed:
1227 unregister_pernet_device(&xfrmi_net_ops);
1228 pernet_dev_failed:
1229 pr_err("xfrmi init: failed to register %s\n", msg);
1230 return err;
1231 }
1232
1233 static void __exit xfrmi_fini(void)
1234 {
1235 xfrm_if_unregister_cb();
1236 lwtunnel_encap_del_ops(&xfrmi_encap_ops, LWTUNNEL_ENCAP_XFRM);
1237 rtnl_link_unregister(&xfrmi_link_ops);
1238 xfrmi4_fini();
1239 xfrmi6_fini();
1240 unregister_pernet_device(&xfrmi_net_ops);
1241 }
1242
1243 module_init(xfrmi_init);
1244 module_exit(xfrmi_fini);
1245 MODULE_LICENSE("GPL");
1246 MODULE_ALIAS_RTNL_LINK("xfrm");
1247 MODULE_ALIAS_NETDEV("xfrm0");
1248 MODULE_AUTHOR("Steffen Klassert");
1249 MODULE_DESCRIPTION("XFRM virtual interface");
1250
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