xref: /openbmc/linux/net/ipv4/ip_vti.c (revision 9eda7c1f)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *	Linux NET3: IP/IP protocol decoder modified to support
4  *		    virtual tunnel interface
5  *
6  *	Authors:
7  *		Saurabh Mohan (saurabh.mohan@vyatta.com) 05/07/2012
8  */
9 
10 /*
11    This version of net/ipv4/ip_vti.c is cloned of net/ipv4/ipip.c
12 
13    For comments look at net/ipv4/ip_gre.c --ANK
14  */
15 
16 
17 #include <linux/capability.h>
18 #include <linux/module.h>
19 #include <linux/types.h>
20 #include <linux/kernel.h>
21 #include <linux/uaccess.h>
22 #include <linux/skbuff.h>
23 #include <linux/netdevice.h>
24 #include <linux/in.h>
25 #include <linux/tcp.h>
26 #include <linux/udp.h>
27 #include <linux/if_arp.h>
28 #include <linux/init.h>
29 #include <linux/netfilter_ipv4.h>
30 #include <linux/if_ether.h>
31 #include <linux/icmpv6.h>
32 
33 #include <net/sock.h>
34 #include <net/ip.h>
35 #include <net/icmp.h>
36 #include <net/ip_tunnels.h>
37 #include <net/inet_ecn.h>
38 #include <net/xfrm.h>
39 #include <net/net_namespace.h>
40 #include <net/netns/generic.h>
41 
42 static struct rtnl_link_ops vti_link_ops __read_mostly;
43 
44 static unsigned int vti_net_id __read_mostly;
45 static int vti_tunnel_init(struct net_device *dev);
46 
47 static int vti_input(struct sk_buff *skb, int nexthdr, __be32 spi,
48 		     int encap_type, bool update_skb_dev)
49 {
50 	struct ip_tunnel *tunnel;
51 	const struct iphdr *iph = ip_hdr(skb);
52 	struct net *net = dev_net(skb->dev);
53 	struct ip_tunnel_net *itn = net_generic(net, vti_net_id);
54 
55 	tunnel = ip_tunnel_lookup(itn, skb->dev->ifindex, TUNNEL_NO_KEY,
56 				  iph->saddr, iph->daddr, 0);
57 	if (tunnel) {
58 		if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb))
59 			goto drop;
60 
61 		XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip4 = tunnel;
62 
63 		if (update_skb_dev)
64 			skb->dev = tunnel->dev;
65 
66 		return xfrm_input(skb, nexthdr, spi, encap_type);
67 	}
68 
69 	return -EINVAL;
70 drop:
71 	kfree_skb(skb);
72 	return 0;
73 }
74 
75 static int vti_input_proto(struct sk_buff *skb, int nexthdr, __be32 spi,
76 			   int encap_type)
77 {
78 	return vti_input(skb, nexthdr, spi, encap_type, false);
79 }
80 
81 static int vti_rcv(struct sk_buff *skb, __be32 spi, bool update_skb_dev)
82 {
83 	XFRM_SPI_SKB_CB(skb)->family = AF_INET;
84 	XFRM_SPI_SKB_CB(skb)->daddroff = offsetof(struct iphdr, daddr);
85 
86 	return vti_input(skb, ip_hdr(skb)->protocol, spi, 0, update_skb_dev);
87 }
88 
89 static int vti_rcv_proto(struct sk_buff *skb)
90 {
91 	return vti_rcv(skb, 0, false);
92 }
93 
94 static int vti_rcv_cb(struct sk_buff *skb, int err)
95 {
96 	unsigned short family;
97 	struct net_device *dev;
98 	struct pcpu_sw_netstats *tstats;
99 	struct xfrm_state *x;
100 	const struct xfrm_mode *inner_mode;
101 	struct ip_tunnel *tunnel = XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip4;
102 	u32 orig_mark = skb->mark;
103 	int ret;
104 
105 	if (!tunnel)
106 		return 1;
107 
108 	dev = tunnel->dev;
109 
110 	if (err) {
111 		dev->stats.rx_errors++;
112 		dev->stats.rx_dropped++;
113 
114 		return 0;
115 	}
116 
117 	x = xfrm_input_state(skb);
118 
119 	inner_mode = &x->inner_mode;
120 
121 	if (x->sel.family == AF_UNSPEC) {
122 		inner_mode = xfrm_ip2inner_mode(x, XFRM_MODE_SKB_CB(skb)->protocol);
123 		if (inner_mode == NULL) {
124 			XFRM_INC_STATS(dev_net(skb->dev),
125 				       LINUX_MIB_XFRMINSTATEMODEERROR);
126 			return -EINVAL;
127 		}
128 	}
129 
130 	family = inner_mode->family;
131 
132 	skb->mark = be32_to_cpu(tunnel->parms.i_key);
133 	ret = xfrm_policy_check(NULL, XFRM_POLICY_IN, skb, family);
134 	skb->mark = orig_mark;
135 
136 	if (!ret)
137 		return -EPERM;
138 
139 	skb_scrub_packet(skb, !net_eq(tunnel->net, dev_net(skb->dev)));
140 	skb->dev = dev;
141 
142 	tstats = this_cpu_ptr(dev->tstats);
143 
144 	u64_stats_update_begin(&tstats->syncp);
145 	tstats->rx_packets++;
146 	tstats->rx_bytes += skb->len;
147 	u64_stats_update_end(&tstats->syncp);
148 
149 	return 0;
150 }
151 
152 static bool vti_state_check(const struct xfrm_state *x, __be32 dst, __be32 src)
153 {
154 	xfrm_address_t *daddr = (xfrm_address_t *)&dst;
155 	xfrm_address_t *saddr = (xfrm_address_t *)&src;
156 
157 	/* if there is no transform then this tunnel is not functional.
158 	 * Or if the xfrm is not mode tunnel.
159 	 */
160 	if (!x || x->props.mode != XFRM_MODE_TUNNEL ||
161 	    x->props.family != AF_INET)
162 		return false;
163 
164 	if (!dst)
165 		return xfrm_addr_equal(saddr, &x->props.saddr, AF_INET);
166 
167 	if (!xfrm_state_addr_check(x, daddr, saddr, AF_INET))
168 		return false;
169 
170 	return true;
171 }
172 
173 static netdev_tx_t vti_xmit(struct sk_buff *skb, struct net_device *dev,
174 			    struct flowi *fl)
175 {
176 	struct ip_tunnel *tunnel = netdev_priv(dev);
177 	struct ip_tunnel_parm *parms = &tunnel->parms;
178 	struct dst_entry *dst = skb_dst(skb);
179 	struct net_device *tdev;	/* Device to other host */
180 	int pkt_len = skb->len;
181 	int err;
182 	int mtu;
183 
184 	if (!dst) {
185 		switch (skb->protocol) {
186 		case htons(ETH_P_IP): {
187 			struct rtable *rt;
188 
189 			fl->u.ip4.flowi4_oif = dev->ifindex;
190 			fl->u.ip4.flowi4_flags |= FLOWI_FLAG_ANYSRC;
191 			rt = __ip_route_output_key(dev_net(dev), &fl->u.ip4);
192 			if (IS_ERR(rt)) {
193 				dev->stats.tx_carrier_errors++;
194 				goto tx_error_icmp;
195 			}
196 			dst = &rt->dst;
197 			skb_dst_set(skb, dst);
198 			break;
199 		}
200 #if IS_ENABLED(CONFIG_IPV6)
201 		case htons(ETH_P_IPV6):
202 			fl->u.ip6.flowi6_oif = dev->ifindex;
203 			fl->u.ip6.flowi6_flags |= FLOWI_FLAG_ANYSRC;
204 			dst = ip6_route_output(dev_net(dev), NULL, &fl->u.ip6);
205 			if (dst->error) {
206 				dst_release(dst);
207 				dst = NULL;
208 				dev->stats.tx_carrier_errors++;
209 				goto tx_error_icmp;
210 			}
211 			skb_dst_set(skb, dst);
212 			break;
213 #endif
214 		default:
215 			dev->stats.tx_carrier_errors++;
216 			goto tx_error_icmp;
217 		}
218 	}
219 
220 	dst_hold(dst);
221 	dst = xfrm_lookup_route(tunnel->net, dst, fl, NULL, 0);
222 	if (IS_ERR(dst)) {
223 		dev->stats.tx_carrier_errors++;
224 		goto tx_error_icmp;
225 	}
226 
227 	if (dst->flags & DST_XFRM_QUEUE)
228 		goto queued;
229 
230 	if (!vti_state_check(dst->xfrm, parms->iph.daddr, parms->iph.saddr)) {
231 		dev->stats.tx_carrier_errors++;
232 		dst_release(dst);
233 		goto tx_error_icmp;
234 	}
235 
236 	tdev = dst->dev;
237 
238 	if (tdev == dev) {
239 		dst_release(dst);
240 		dev->stats.collisions++;
241 		goto tx_error;
242 	}
243 
244 	mtu = dst_mtu(dst);
245 	if (skb->len > mtu) {
246 		skb_dst_update_pmtu_no_confirm(skb, mtu);
247 		if (skb->protocol == htons(ETH_P_IP)) {
248 			icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
249 				  htonl(mtu));
250 		} else {
251 			if (mtu < IPV6_MIN_MTU)
252 				mtu = IPV6_MIN_MTU;
253 
254 			icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
255 		}
256 
257 		dst_release(dst);
258 		goto tx_error;
259 	}
260 
261 queued:
262 	skb_scrub_packet(skb, !net_eq(tunnel->net, dev_net(dev)));
263 	skb_dst_set(skb, dst);
264 	skb->dev = skb_dst(skb)->dev;
265 
266 	err = dst_output(tunnel->net, skb->sk, skb);
267 	if (net_xmit_eval(err) == 0)
268 		err = pkt_len;
269 	iptunnel_xmit_stats(dev, err);
270 	return NETDEV_TX_OK;
271 
272 tx_error_icmp:
273 	dst_link_failure(skb);
274 tx_error:
275 	dev->stats.tx_errors++;
276 	kfree_skb(skb);
277 	return NETDEV_TX_OK;
278 }
279 
280 /* This function assumes it is being called from dev_queue_xmit()
281  * and that skb is filled properly by that function.
282  */
283 static netdev_tx_t vti_tunnel_xmit(struct sk_buff *skb, struct net_device *dev)
284 {
285 	struct ip_tunnel *tunnel = netdev_priv(dev);
286 	struct flowi fl;
287 
288 	if (!pskb_inet_may_pull(skb))
289 		goto tx_err;
290 
291 	memset(&fl, 0, sizeof(fl));
292 
293 	switch (skb->protocol) {
294 	case htons(ETH_P_IP):
295 		xfrm_decode_session(skb, &fl, AF_INET);
296 		memset(IPCB(skb), 0, sizeof(*IPCB(skb)));
297 		break;
298 	case htons(ETH_P_IPV6):
299 		xfrm_decode_session(skb, &fl, AF_INET6);
300 		memset(IP6CB(skb), 0, sizeof(*IP6CB(skb)));
301 		break;
302 	default:
303 		goto tx_err;
304 	}
305 
306 	/* override mark with tunnel output key */
307 	fl.flowi_mark = be32_to_cpu(tunnel->parms.o_key);
308 
309 	return vti_xmit(skb, dev, &fl);
310 
311 tx_err:
312 	dev->stats.tx_errors++;
313 	kfree_skb(skb);
314 	return NETDEV_TX_OK;
315 }
316 
317 static int vti4_err(struct sk_buff *skb, u32 info)
318 {
319 	__be32 spi;
320 	__u32 mark;
321 	struct xfrm_state *x;
322 	struct ip_tunnel *tunnel;
323 	struct ip_esp_hdr *esph;
324 	struct ip_auth_hdr *ah ;
325 	struct ip_comp_hdr *ipch;
326 	struct net *net = dev_net(skb->dev);
327 	const struct iphdr *iph = (const struct iphdr *)skb->data;
328 	int protocol = iph->protocol;
329 	struct ip_tunnel_net *itn = net_generic(net, vti_net_id);
330 
331 	tunnel = ip_tunnel_lookup(itn, skb->dev->ifindex, TUNNEL_NO_KEY,
332 				  iph->daddr, iph->saddr, 0);
333 	if (!tunnel)
334 		return -1;
335 
336 	mark = be32_to_cpu(tunnel->parms.o_key);
337 
338 	switch (protocol) {
339 	case IPPROTO_ESP:
340 		esph = (struct ip_esp_hdr *)(skb->data+(iph->ihl<<2));
341 		spi = esph->spi;
342 		break;
343 	case IPPROTO_AH:
344 		ah = (struct ip_auth_hdr *)(skb->data+(iph->ihl<<2));
345 		spi = ah->spi;
346 		break;
347 	case IPPROTO_COMP:
348 		ipch = (struct ip_comp_hdr *)(skb->data+(iph->ihl<<2));
349 		spi = htonl(ntohs(ipch->cpi));
350 		break;
351 	default:
352 		return 0;
353 	}
354 
355 	switch (icmp_hdr(skb)->type) {
356 	case ICMP_DEST_UNREACH:
357 		if (icmp_hdr(skb)->code != ICMP_FRAG_NEEDED)
358 			return 0;
359 	case ICMP_REDIRECT:
360 		break;
361 	default:
362 		return 0;
363 	}
364 
365 	x = xfrm_state_lookup(net, mark, (const xfrm_address_t *)&iph->daddr,
366 			      spi, protocol, AF_INET);
367 	if (!x)
368 		return 0;
369 
370 	if (icmp_hdr(skb)->type == ICMP_DEST_UNREACH)
371 		ipv4_update_pmtu(skb, net, info, 0, protocol);
372 	else
373 		ipv4_redirect(skb, net, 0, protocol);
374 	xfrm_state_put(x);
375 
376 	return 0;
377 }
378 
379 static int
380 vti_tunnel_ctl(struct net_device *dev, struct ip_tunnel_parm *p, int cmd)
381 {
382 	int err = 0;
383 
384 	if (cmd == SIOCADDTUNNEL || cmd == SIOCCHGTUNNEL) {
385 		if (p->iph.version != 4 || p->iph.protocol != IPPROTO_IPIP ||
386 		    p->iph.ihl != 5)
387 			return -EINVAL;
388 	}
389 
390 	if (!(p->i_flags & GRE_KEY))
391 		p->i_key = 0;
392 	if (!(p->o_flags & GRE_KEY))
393 		p->o_key = 0;
394 
395 	p->i_flags = VTI_ISVTI;
396 
397 	err = ip_tunnel_ctl(dev, p, cmd);
398 	if (err)
399 		return err;
400 
401 	if (cmd != SIOCDELTUNNEL) {
402 		p->i_flags |= GRE_KEY;
403 		p->o_flags |= GRE_KEY;
404 	}
405 	return 0;
406 }
407 
408 static const struct net_device_ops vti_netdev_ops = {
409 	.ndo_init	= vti_tunnel_init,
410 	.ndo_uninit	= ip_tunnel_uninit,
411 	.ndo_start_xmit	= vti_tunnel_xmit,
412 	.ndo_do_ioctl	= ip_tunnel_ioctl,
413 	.ndo_change_mtu	= ip_tunnel_change_mtu,
414 	.ndo_get_stats64 = ip_tunnel_get_stats64,
415 	.ndo_get_iflink = ip_tunnel_get_iflink,
416 	.ndo_tunnel_ctl	= vti_tunnel_ctl,
417 };
418 
419 static void vti_tunnel_setup(struct net_device *dev)
420 {
421 	dev->netdev_ops		= &vti_netdev_ops;
422 	dev->header_ops		= &ip_tunnel_header_ops;
423 	dev->type		= ARPHRD_TUNNEL;
424 	ip_tunnel_setup(dev, vti_net_id);
425 }
426 
427 static int vti_tunnel_init(struct net_device *dev)
428 {
429 	struct ip_tunnel *tunnel = netdev_priv(dev);
430 	struct iphdr *iph = &tunnel->parms.iph;
431 
432 	memcpy(dev->dev_addr, &iph->saddr, 4);
433 	memcpy(dev->broadcast, &iph->daddr, 4);
434 
435 	dev->flags		= IFF_NOARP;
436 	dev->addr_len		= 4;
437 	dev->features		|= NETIF_F_LLTX;
438 	netif_keep_dst(dev);
439 
440 	return ip_tunnel_init(dev);
441 }
442 
443 static void __net_init vti_fb_tunnel_init(struct net_device *dev)
444 {
445 	struct ip_tunnel *tunnel = netdev_priv(dev);
446 	struct iphdr *iph = &tunnel->parms.iph;
447 
448 	iph->version		= 4;
449 	iph->protocol		= IPPROTO_IPIP;
450 	iph->ihl		= 5;
451 }
452 
453 static struct xfrm4_protocol vti_esp4_protocol __read_mostly = {
454 	.handler	=	vti_rcv_proto,
455 	.input_handler	=	vti_input_proto,
456 	.cb_handler	=	vti_rcv_cb,
457 	.err_handler	=	vti4_err,
458 	.priority	=	100,
459 };
460 
461 static struct xfrm4_protocol vti_ah4_protocol __read_mostly = {
462 	.handler	=	vti_rcv_proto,
463 	.input_handler	=	vti_input_proto,
464 	.cb_handler	=	vti_rcv_cb,
465 	.err_handler	=	vti4_err,
466 	.priority	=	100,
467 };
468 
469 static struct xfrm4_protocol vti_ipcomp4_protocol __read_mostly = {
470 	.handler	=	vti_rcv_proto,
471 	.input_handler	=	vti_input_proto,
472 	.cb_handler	=	vti_rcv_cb,
473 	.err_handler	=	vti4_err,
474 	.priority	=	100,
475 };
476 
477 #if IS_ENABLED(CONFIG_INET_XFRM_TUNNEL)
478 static int vti_rcv_tunnel(struct sk_buff *skb)
479 {
480 	XFRM_SPI_SKB_CB(skb)->family = AF_INET;
481 	XFRM_SPI_SKB_CB(skb)->daddroff = offsetof(struct iphdr, daddr);
482 
483 	return vti_input(skb, IPPROTO_IPIP, ip_hdr(skb)->saddr, 0, false);
484 }
485 
486 static struct xfrm_tunnel vti_ipip_handler __read_mostly = {
487 	.handler	=	vti_rcv_tunnel,
488 	.cb_handler	=	vti_rcv_cb,
489 	.err_handler	=	vti4_err,
490 	.priority	=	0,
491 };
492 
493 static struct xfrm_tunnel vti_ipip6_handler __read_mostly = {
494 	.handler	=	vti_rcv_tunnel,
495 	.cb_handler	=	vti_rcv_cb,
496 	.err_handler	=	vti4_err,
497 	.priority	=	0,
498 };
499 #endif
500 
501 static int __net_init vti_init_net(struct net *net)
502 {
503 	int err;
504 	struct ip_tunnel_net *itn;
505 
506 	err = ip_tunnel_init_net(net, vti_net_id, &vti_link_ops, "ip_vti0");
507 	if (err)
508 		return err;
509 	itn = net_generic(net, vti_net_id);
510 	if (itn->fb_tunnel_dev)
511 		vti_fb_tunnel_init(itn->fb_tunnel_dev);
512 	return 0;
513 }
514 
515 static void __net_exit vti_exit_batch_net(struct list_head *list_net)
516 {
517 	ip_tunnel_delete_nets(list_net, vti_net_id, &vti_link_ops);
518 }
519 
520 static struct pernet_operations vti_net_ops = {
521 	.init = vti_init_net,
522 	.exit_batch = vti_exit_batch_net,
523 	.id   = &vti_net_id,
524 	.size = sizeof(struct ip_tunnel_net),
525 };
526 
527 static int vti_tunnel_validate(struct nlattr *tb[], struct nlattr *data[],
528 			       struct netlink_ext_ack *extack)
529 {
530 	return 0;
531 }
532 
533 static void vti_netlink_parms(struct nlattr *data[],
534 			      struct ip_tunnel_parm *parms,
535 			      __u32 *fwmark)
536 {
537 	memset(parms, 0, sizeof(*parms));
538 
539 	parms->iph.protocol = IPPROTO_IPIP;
540 
541 	if (!data)
542 		return;
543 
544 	parms->i_flags = VTI_ISVTI;
545 
546 	if (data[IFLA_VTI_LINK])
547 		parms->link = nla_get_u32(data[IFLA_VTI_LINK]);
548 
549 	if (data[IFLA_VTI_IKEY])
550 		parms->i_key = nla_get_be32(data[IFLA_VTI_IKEY]);
551 
552 	if (data[IFLA_VTI_OKEY])
553 		parms->o_key = nla_get_be32(data[IFLA_VTI_OKEY]);
554 
555 	if (data[IFLA_VTI_LOCAL])
556 		parms->iph.saddr = nla_get_in_addr(data[IFLA_VTI_LOCAL]);
557 
558 	if (data[IFLA_VTI_REMOTE])
559 		parms->iph.daddr = nla_get_in_addr(data[IFLA_VTI_REMOTE]);
560 
561 	if (data[IFLA_VTI_FWMARK])
562 		*fwmark = nla_get_u32(data[IFLA_VTI_FWMARK]);
563 }
564 
565 static int vti_newlink(struct net *src_net, struct net_device *dev,
566 		       struct nlattr *tb[], struct nlattr *data[],
567 		       struct netlink_ext_ack *extack)
568 {
569 	struct ip_tunnel_parm parms;
570 	__u32 fwmark = 0;
571 
572 	vti_netlink_parms(data, &parms, &fwmark);
573 	return ip_tunnel_newlink(dev, tb, &parms, fwmark);
574 }
575 
576 static int vti_changelink(struct net_device *dev, struct nlattr *tb[],
577 			  struct nlattr *data[],
578 			  struct netlink_ext_ack *extack)
579 {
580 	struct ip_tunnel *t = netdev_priv(dev);
581 	__u32 fwmark = t->fwmark;
582 	struct ip_tunnel_parm p;
583 
584 	vti_netlink_parms(data, &p, &fwmark);
585 	return ip_tunnel_changelink(dev, tb, &p, fwmark);
586 }
587 
588 static size_t vti_get_size(const struct net_device *dev)
589 {
590 	return
591 		/* IFLA_VTI_LINK */
592 		nla_total_size(4) +
593 		/* IFLA_VTI_IKEY */
594 		nla_total_size(4) +
595 		/* IFLA_VTI_OKEY */
596 		nla_total_size(4) +
597 		/* IFLA_VTI_LOCAL */
598 		nla_total_size(4) +
599 		/* IFLA_VTI_REMOTE */
600 		nla_total_size(4) +
601 		/* IFLA_VTI_FWMARK */
602 		nla_total_size(4) +
603 		0;
604 }
605 
606 static int vti_fill_info(struct sk_buff *skb, const struct net_device *dev)
607 {
608 	struct ip_tunnel *t = netdev_priv(dev);
609 	struct ip_tunnel_parm *p = &t->parms;
610 
611 	if (nla_put_u32(skb, IFLA_VTI_LINK, p->link) ||
612 	    nla_put_be32(skb, IFLA_VTI_IKEY, p->i_key) ||
613 	    nla_put_be32(skb, IFLA_VTI_OKEY, p->o_key) ||
614 	    nla_put_in_addr(skb, IFLA_VTI_LOCAL, p->iph.saddr) ||
615 	    nla_put_in_addr(skb, IFLA_VTI_REMOTE, p->iph.daddr) ||
616 	    nla_put_u32(skb, IFLA_VTI_FWMARK, t->fwmark))
617 		return -EMSGSIZE;
618 
619 	return 0;
620 }
621 
622 static const struct nla_policy vti_policy[IFLA_VTI_MAX + 1] = {
623 	[IFLA_VTI_LINK]		= { .type = NLA_U32 },
624 	[IFLA_VTI_IKEY]		= { .type = NLA_U32 },
625 	[IFLA_VTI_OKEY]		= { .type = NLA_U32 },
626 	[IFLA_VTI_LOCAL]	= { .len = sizeof_field(struct iphdr, saddr) },
627 	[IFLA_VTI_REMOTE]	= { .len = sizeof_field(struct iphdr, daddr) },
628 	[IFLA_VTI_FWMARK]	= { .type = NLA_U32 },
629 };
630 
631 static struct rtnl_link_ops vti_link_ops __read_mostly = {
632 	.kind		= "vti",
633 	.maxtype	= IFLA_VTI_MAX,
634 	.policy		= vti_policy,
635 	.priv_size	= sizeof(struct ip_tunnel),
636 	.setup		= vti_tunnel_setup,
637 	.validate	= vti_tunnel_validate,
638 	.newlink	= vti_newlink,
639 	.changelink	= vti_changelink,
640 	.dellink        = ip_tunnel_dellink,
641 	.get_size	= vti_get_size,
642 	.fill_info	= vti_fill_info,
643 	.get_link_net	= ip_tunnel_get_link_net,
644 };
645 
646 static int __init vti_init(void)
647 {
648 	const char *msg;
649 	int err;
650 
651 	pr_info("IPv4 over IPsec tunneling driver\n");
652 
653 	msg = "tunnel device";
654 	err = register_pernet_device(&vti_net_ops);
655 	if (err < 0)
656 		goto pernet_dev_failed;
657 
658 	msg = "tunnel protocols";
659 	err = xfrm4_protocol_register(&vti_esp4_protocol, IPPROTO_ESP);
660 	if (err < 0)
661 		goto xfrm_proto_esp_failed;
662 	err = xfrm4_protocol_register(&vti_ah4_protocol, IPPROTO_AH);
663 	if (err < 0)
664 		goto xfrm_proto_ah_failed;
665 	err = xfrm4_protocol_register(&vti_ipcomp4_protocol, IPPROTO_COMP);
666 	if (err < 0)
667 		goto xfrm_proto_comp_failed;
668 
669 #if IS_ENABLED(CONFIG_INET_XFRM_TUNNEL)
670 	msg = "ipip tunnel";
671 	err = xfrm4_tunnel_register(&vti_ipip_handler, AF_INET);
672 	if (err < 0)
673 		goto xfrm_tunnel_ipip_failed;
674 #if IS_ENABLED(CONFIG_IPV6)
675 	err = xfrm4_tunnel_register(&vti_ipip6_handler, AF_INET6);
676 	if (err < 0)
677 		goto xfrm_tunnel_ipip6_failed;
678 #endif
679 #endif
680 
681 	msg = "netlink interface";
682 	err = rtnl_link_register(&vti_link_ops);
683 	if (err < 0)
684 		goto rtnl_link_failed;
685 
686 	return err;
687 
688 rtnl_link_failed:
689 #if IS_ENABLED(CONFIG_INET_XFRM_TUNNEL)
690 #if IS_ENABLED(CONFIG_IPV6)
691 	xfrm4_tunnel_deregister(&vti_ipip6_handler, AF_INET6);
692 xfrm_tunnel_ipip6_failed:
693 #endif
694 	xfrm4_tunnel_deregister(&vti_ipip_handler, AF_INET);
695 xfrm_tunnel_ipip_failed:
696 #endif
697 	xfrm4_protocol_deregister(&vti_ipcomp4_protocol, IPPROTO_COMP);
698 xfrm_proto_comp_failed:
699 	xfrm4_protocol_deregister(&vti_ah4_protocol, IPPROTO_AH);
700 xfrm_proto_ah_failed:
701 	xfrm4_protocol_deregister(&vti_esp4_protocol, IPPROTO_ESP);
702 xfrm_proto_esp_failed:
703 	unregister_pernet_device(&vti_net_ops);
704 pernet_dev_failed:
705 	pr_err("vti init: failed to register %s\n", msg);
706 	return err;
707 }
708 
709 static void __exit vti_fini(void)
710 {
711 	rtnl_link_unregister(&vti_link_ops);
712 #if IS_ENABLED(CONFIG_INET_XFRM_TUNNEL)
713 #if IS_ENABLED(CONFIG_IPV6)
714 	xfrm4_tunnel_deregister(&vti_ipip6_handler, AF_INET6);
715 #endif
716 	xfrm4_tunnel_deregister(&vti_ipip_handler, AF_INET);
717 #endif
718 	xfrm4_protocol_deregister(&vti_ipcomp4_protocol, IPPROTO_COMP);
719 	xfrm4_protocol_deregister(&vti_ah4_protocol, IPPROTO_AH);
720 	xfrm4_protocol_deregister(&vti_esp4_protocol, IPPROTO_ESP);
721 	unregister_pernet_device(&vti_net_ops);
722 }
723 
724 module_init(vti_init);
725 module_exit(vti_fini);
726 MODULE_LICENSE("GPL");
727 MODULE_ALIAS_RTNL_LINK("vti");
728 MODULE_ALIAS_NETDEV("ip_vti0");
729