xref: /linux/net/ipv4/ip_vti.c (revision d1626a1c273d0e66834006b10ebe12062dce2b6f)
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 xfrm_state *x;
99 	const struct xfrm_mode *inner_mode;
100 	struct ip_tunnel *tunnel = XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip4;
101 	u32 orig_mark = skb->mark;
102 	int ret;
103 
104 	if (!tunnel)
105 		return 1;
106 
107 	dev = tunnel->dev;
108 
109 	if (err) {
110 		dev->stats.rx_errors++;
111 		dev->stats.rx_dropped++;
112 
113 		return 0;
114 	}
115 
116 	x = xfrm_input_state(skb);
117 
118 	inner_mode = &x->inner_mode;
119 
120 	if (x->sel.family == AF_UNSPEC) {
121 		inner_mode = xfrm_ip2inner_mode(x, XFRM_MODE_SKB_CB(skb)->protocol);
122 		if (inner_mode == NULL) {
123 			XFRM_INC_STATS(dev_net(skb->dev),
124 				       LINUX_MIB_XFRMINSTATEMODEERROR);
125 			return -EINVAL;
126 		}
127 	}
128 
129 	family = inner_mode->family;
130 
131 	skb->mark = be32_to_cpu(tunnel->parms.i_key);
132 	ret = xfrm_policy_check(NULL, XFRM_POLICY_IN, skb, family);
133 	skb->mark = orig_mark;
134 
135 	if (!ret)
136 		return -EPERM;
137 
138 	skb_scrub_packet(skb, !net_eq(tunnel->net, dev_net(skb->dev)));
139 	skb->dev = dev;
140 	dev_sw_netstats_rx_add(dev, skb->len);
141 
142 	return 0;
143 }
144 
145 static bool vti_state_check(const struct xfrm_state *x, __be32 dst, __be32 src)
146 {
147 	xfrm_address_t *daddr = (xfrm_address_t *)&dst;
148 	xfrm_address_t *saddr = (xfrm_address_t *)&src;
149 
150 	/* if there is no transform then this tunnel is not functional.
151 	 * Or if the xfrm is not mode tunnel.
152 	 */
153 	if (!x || x->props.mode != XFRM_MODE_TUNNEL ||
154 	    x->props.family != AF_INET)
155 		return false;
156 
157 	if (!dst)
158 		return xfrm_addr_equal(saddr, &x->props.saddr, AF_INET);
159 
160 	if (!xfrm_state_addr_check(x, daddr, saddr, AF_INET))
161 		return false;
162 
163 	return true;
164 }
165 
166 static netdev_tx_t vti_xmit(struct sk_buff *skb, struct net_device *dev,
167 			    struct flowi *fl)
168 {
169 	struct ip_tunnel *tunnel = netdev_priv(dev);
170 	struct ip_tunnel_parm *parms = &tunnel->parms;
171 	struct dst_entry *dst = skb_dst(skb);
172 	struct net_device *tdev;	/* Device to other host */
173 	int pkt_len = skb->len;
174 	int err;
175 	int mtu;
176 
177 	if (!dst) {
178 		switch (skb->protocol) {
179 		case htons(ETH_P_IP): {
180 			struct rtable *rt;
181 
182 			fl->u.ip4.flowi4_oif = dev->ifindex;
183 			fl->u.ip4.flowi4_flags |= FLOWI_FLAG_ANYSRC;
184 			rt = __ip_route_output_key(dev_net(dev), &fl->u.ip4);
185 			if (IS_ERR(rt)) {
186 				dev->stats.tx_carrier_errors++;
187 				goto tx_error_icmp;
188 			}
189 			dst = &rt->dst;
190 			skb_dst_set(skb, dst);
191 			break;
192 		}
193 #if IS_ENABLED(CONFIG_IPV6)
194 		case htons(ETH_P_IPV6):
195 			fl->u.ip6.flowi6_oif = dev->ifindex;
196 			fl->u.ip6.flowi6_flags |= FLOWI_FLAG_ANYSRC;
197 			dst = ip6_route_output(dev_net(dev), NULL, &fl->u.ip6);
198 			if (dst->error) {
199 				dst_release(dst);
200 				dst = NULL;
201 				dev->stats.tx_carrier_errors++;
202 				goto tx_error_icmp;
203 			}
204 			skb_dst_set(skb, dst);
205 			break;
206 #endif
207 		default:
208 			dev->stats.tx_carrier_errors++;
209 			goto tx_error_icmp;
210 		}
211 	}
212 
213 	dst_hold(dst);
214 	dst = xfrm_lookup_route(tunnel->net, dst, fl, NULL, 0);
215 	if (IS_ERR(dst)) {
216 		dev->stats.tx_carrier_errors++;
217 		goto tx_error_icmp;
218 	}
219 
220 	if (dst->flags & DST_XFRM_QUEUE)
221 		goto xmit;
222 
223 	if (!vti_state_check(dst->xfrm, parms->iph.daddr, parms->iph.saddr)) {
224 		dev->stats.tx_carrier_errors++;
225 		dst_release(dst);
226 		goto tx_error_icmp;
227 	}
228 
229 	tdev = dst->dev;
230 
231 	if (tdev == dev) {
232 		dst_release(dst);
233 		dev->stats.collisions++;
234 		goto tx_error;
235 	}
236 
237 	mtu = dst_mtu(dst);
238 	if (skb->len > mtu) {
239 		skb_dst_update_pmtu_no_confirm(skb, mtu);
240 		if (skb->protocol == htons(ETH_P_IP)) {
241 			if (!(ip_hdr(skb)->frag_off & htons(IP_DF)))
242 				goto xmit;
243 			icmp_ndo_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
244 				      htonl(mtu));
245 		} else {
246 			if (mtu < IPV6_MIN_MTU)
247 				mtu = IPV6_MIN_MTU;
248 
249 			icmpv6_ndo_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
250 		}
251 
252 		dst_release(dst);
253 		goto tx_error;
254 	}
255 
256 xmit:
257 	skb_scrub_packet(skb, !net_eq(tunnel->net, dev_net(dev)));
258 	skb_dst_set(skb, dst);
259 	skb->dev = skb_dst(skb)->dev;
260 
261 	err = dst_output(tunnel->net, skb->sk, skb);
262 	if (net_xmit_eval(err) == 0)
263 		err = pkt_len;
264 	iptunnel_xmit_stats(dev, err);
265 	return NETDEV_TX_OK;
266 
267 tx_error_icmp:
268 	dst_link_failure(skb);
269 tx_error:
270 	dev->stats.tx_errors++;
271 	kfree_skb(skb);
272 	return NETDEV_TX_OK;
273 }
274 
275 /* This function assumes it is being called from dev_queue_xmit()
276  * and that skb is filled properly by that function.
277  */
278 static netdev_tx_t vti_tunnel_xmit(struct sk_buff *skb, struct net_device *dev)
279 {
280 	struct ip_tunnel *tunnel = netdev_priv(dev);
281 	struct flowi fl;
282 
283 	if (!pskb_inet_may_pull(skb))
284 		goto tx_err;
285 
286 	memset(&fl, 0, sizeof(fl));
287 
288 	switch (skb->protocol) {
289 	case htons(ETH_P_IP):
290 		xfrm_decode_session(skb, &fl, AF_INET);
291 		memset(IPCB(skb), 0, sizeof(*IPCB(skb)));
292 		break;
293 	case htons(ETH_P_IPV6):
294 		xfrm_decode_session(skb, &fl, AF_INET6);
295 		memset(IP6CB(skb), 0, sizeof(*IP6CB(skb)));
296 		break;
297 	default:
298 		goto tx_err;
299 	}
300 
301 	/* override mark with tunnel output key */
302 	fl.flowi_mark = be32_to_cpu(tunnel->parms.o_key);
303 
304 	return vti_xmit(skb, dev, &fl);
305 
306 tx_err:
307 	dev->stats.tx_errors++;
308 	kfree_skb(skb);
309 	return NETDEV_TX_OK;
310 }
311 
312 static int vti4_err(struct sk_buff *skb, u32 info)
313 {
314 	__be32 spi;
315 	__u32 mark;
316 	struct xfrm_state *x;
317 	struct ip_tunnel *tunnel;
318 	struct ip_esp_hdr *esph;
319 	struct ip_auth_hdr *ah ;
320 	struct ip_comp_hdr *ipch;
321 	struct net *net = dev_net(skb->dev);
322 	const struct iphdr *iph = (const struct iphdr *)skb->data;
323 	int protocol = iph->protocol;
324 	struct ip_tunnel_net *itn = net_generic(net, vti_net_id);
325 
326 	tunnel = ip_tunnel_lookup(itn, skb->dev->ifindex, TUNNEL_NO_KEY,
327 				  iph->daddr, iph->saddr, 0);
328 	if (!tunnel)
329 		return -1;
330 
331 	mark = be32_to_cpu(tunnel->parms.o_key);
332 
333 	switch (protocol) {
334 	case IPPROTO_ESP:
335 		esph = (struct ip_esp_hdr *)(skb->data+(iph->ihl<<2));
336 		spi = esph->spi;
337 		break;
338 	case IPPROTO_AH:
339 		ah = (struct ip_auth_hdr *)(skb->data+(iph->ihl<<2));
340 		spi = ah->spi;
341 		break;
342 	case IPPROTO_COMP:
343 		ipch = (struct ip_comp_hdr *)(skb->data+(iph->ihl<<2));
344 		spi = htonl(ntohs(ipch->cpi));
345 		break;
346 	default:
347 		return 0;
348 	}
349 
350 	switch (icmp_hdr(skb)->type) {
351 	case ICMP_DEST_UNREACH:
352 		if (icmp_hdr(skb)->code != ICMP_FRAG_NEEDED)
353 			return 0;
354 		break;
355 	case ICMP_REDIRECT:
356 		break;
357 	default:
358 		return 0;
359 	}
360 
361 	x = xfrm_state_lookup(net, mark, (const xfrm_address_t *)&iph->daddr,
362 			      spi, protocol, AF_INET);
363 	if (!x)
364 		return 0;
365 
366 	if (icmp_hdr(skb)->type == ICMP_DEST_UNREACH)
367 		ipv4_update_pmtu(skb, net, info, 0, protocol);
368 	else
369 		ipv4_redirect(skb, net, 0, protocol);
370 	xfrm_state_put(x);
371 
372 	return 0;
373 }
374 
375 static int
376 vti_tunnel_ctl(struct net_device *dev, struct ip_tunnel_parm *p, int cmd)
377 {
378 	int err = 0;
379 
380 	if (cmd == SIOCADDTUNNEL || cmd == SIOCCHGTUNNEL) {
381 		if (p->iph.version != 4 || p->iph.protocol != IPPROTO_IPIP ||
382 		    p->iph.ihl != 5)
383 			return -EINVAL;
384 	}
385 
386 	if (!(p->i_flags & GRE_KEY))
387 		p->i_key = 0;
388 	if (!(p->o_flags & GRE_KEY))
389 		p->o_key = 0;
390 
391 	p->i_flags = VTI_ISVTI;
392 
393 	err = ip_tunnel_ctl(dev, p, cmd);
394 	if (err)
395 		return err;
396 
397 	if (cmd != SIOCDELTUNNEL) {
398 		p->i_flags |= GRE_KEY;
399 		p->o_flags |= GRE_KEY;
400 	}
401 	return 0;
402 }
403 
404 static const struct net_device_ops vti_netdev_ops = {
405 	.ndo_init	= vti_tunnel_init,
406 	.ndo_uninit	= ip_tunnel_uninit,
407 	.ndo_start_xmit	= vti_tunnel_xmit,
408 	.ndo_siocdevprivate = ip_tunnel_siocdevprivate,
409 	.ndo_change_mtu	= ip_tunnel_change_mtu,
410 	.ndo_get_stats64 = dev_get_tstats64,
411 	.ndo_get_iflink = ip_tunnel_get_iflink,
412 	.ndo_tunnel_ctl	= vti_tunnel_ctl,
413 };
414 
415 static void vti_tunnel_setup(struct net_device *dev)
416 {
417 	dev->netdev_ops		= &vti_netdev_ops;
418 	dev->header_ops		= &ip_tunnel_header_ops;
419 	dev->type		= ARPHRD_TUNNEL;
420 	ip_tunnel_setup(dev, vti_net_id);
421 }
422 
423 static int vti_tunnel_init(struct net_device *dev)
424 {
425 	struct ip_tunnel *tunnel = netdev_priv(dev);
426 	struct iphdr *iph = &tunnel->parms.iph;
427 
428 	memcpy(dev->dev_addr, &iph->saddr, 4);
429 	memcpy(dev->broadcast, &iph->daddr, 4);
430 
431 	dev->flags		= IFF_NOARP;
432 	dev->addr_len		= 4;
433 	dev->features		|= NETIF_F_LLTX;
434 	netif_keep_dst(dev);
435 
436 	return ip_tunnel_init(dev);
437 }
438 
439 static void __net_init vti_fb_tunnel_init(struct net_device *dev)
440 {
441 	struct ip_tunnel *tunnel = netdev_priv(dev);
442 	struct iphdr *iph = &tunnel->parms.iph;
443 
444 	iph->version		= 4;
445 	iph->protocol		= IPPROTO_IPIP;
446 	iph->ihl		= 5;
447 }
448 
449 static struct xfrm4_protocol vti_esp4_protocol __read_mostly = {
450 	.handler	=	vti_rcv_proto,
451 	.input_handler	=	vti_input_proto,
452 	.cb_handler	=	vti_rcv_cb,
453 	.err_handler	=	vti4_err,
454 	.priority	=	100,
455 };
456 
457 static struct xfrm4_protocol vti_ah4_protocol __read_mostly = {
458 	.handler	=	vti_rcv_proto,
459 	.input_handler	=	vti_input_proto,
460 	.cb_handler	=	vti_rcv_cb,
461 	.err_handler	=	vti4_err,
462 	.priority	=	100,
463 };
464 
465 static struct xfrm4_protocol vti_ipcomp4_protocol __read_mostly = {
466 	.handler	=	vti_rcv_proto,
467 	.input_handler	=	vti_input_proto,
468 	.cb_handler	=	vti_rcv_cb,
469 	.err_handler	=	vti4_err,
470 	.priority	=	100,
471 };
472 
473 #if IS_ENABLED(CONFIG_INET_XFRM_TUNNEL)
474 static int vti_rcv_tunnel(struct sk_buff *skb)
475 {
476 	XFRM_SPI_SKB_CB(skb)->family = AF_INET;
477 	XFRM_SPI_SKB_CB(skb)->daddroff = offsetof(struct iphdr, daddr);
478 
479 	return vti_input(skb, IPPROTO_IPIP, ip_hdr(skb)->saddr, 0, false);
480 }
481 
482 static struct xfrm_tunnel vti_ipip_handler __read_mostly = {
483 	.handler	=	vti_rcv_tunnel,
484 	.cb_handler	=	vti_rcv_cb,
485 	.err_handler	=	vti4_err,
486 	.priority	=	0,
487 };
488 
489 #if IS_ENABLED(CONFIG_IPV6)
490 static struct xfrm_tunnel vti_ipip6_handler __read_mostly = {
491 	.handler	=	vti_rcv_tunnel,
492 	.cb_handler	=	vti_rcv_cb,
493 	.err_handler	=	vti4_err,
494 	.priority	=	0,
495 };
496 #endif
497 #endif
498 
499 static int __net_init vti_init_net(struct net *net)
500 {
501 	int err;
502 	struct ip_tunnel_net *itn;
503 
504 	err = ip_tunnel_init_net(net, vti_net_id, &vti_link_ops, "ip_vti0");
505 	if (err)
506 		return err;
507 	itn = net_generic(net, vti_net_id);
508 	if (itn->fb_tunnel_dev)
509 		vti_fb_tunnel_init(itn->fb_tunnel_dev);
510 	return 0;
511 }
512 
513 static void __net_exit vti_exit_batch_net(struct list_head *list_net)
514 {
515 	ip_tunnel_delete_nets(list_net, vti_net_id, &vti_link_ops);
516 }
517 
518 static struct pernet_operations vti_net_ops = {
519 	.init = vti_init_net,
520 	.exit_batch = vti_exit_batch_net,
521 	.id   = &vti_net_id,
522 	.size = sizeof(struct ip_tunnel_net),
523 };
524 
525 static int vti_tunnel_validate(struct nlattr *tb[], struct nlattr *data[],
526 			       struct netlink_ext_ack *extack)
527 {
528 	return 0;
529 }
530 
531 static void vti_netlink_parms(struct nlattr *data[],
532 			      struct ip_tunnel_parm *parms,
533 			      __u32 *fwmark)
534 {
535 	memset(parms, 0, sizeof(*parms));
536 
537 	parms->iph.protocol = IPPROTO_IPIP;
538 
539 	if (!data)
540 		return;
541 
542 	parms->i_flags = VTI_ISVTI;
543 
544 	if (data[IFLA_VTI_LINK])
545 		parms->link = nla_get_u32(data[IFLA_VTI_LINK]);
546 
547 	if (data[IFLA_VTI_IKEY])
548 		parms->i_key = nla_get_be32(data[IFLA_VTI_IKEY]);
549 
550 	if (data[IFLA_VTI_OKEY])
551 		parms->o_key = nla_get_be32(data[IFLA_VTI_OKEY]);
552 
553 	if (data[IFLA_VTI_LOCAL])
554 		parms->iph.saddr = nla_get_in_addr(data[IFLA_VTI_LOCAL]);
555 
556 	if (data[IFLA_VTI_REMOTE])
557 		parms->iph.daddr = nla_get_in_addr(data[IFLA_VTI_REMOTE]);
558 
559 	if (data[IFLA_VTI_FWMARK])
560 		*fwmark = nla_get_u32(data[IFLA_VTI_FWMARK]);
561 }
562 
563 static int vti_newlink(struct net *src_net, struct net_device *dev,
564 		       struct nlattr *tb[], struct nlattr *data[],
565 		       struct netlink_ext_ack *extack)
566 {
567 	struct ip_tunnel_parm parms;
568 	__u32 fwmark = 0;
569 
570 	vti_netlink_parms(data, &parms, &fwmark);
571 	return ip_tunnel_newlink(dev, tb, &parms, fwmark);
572 }
573 
574 static int vti_changelink(struct net_device *dev, struct nlattr *tb[],
575 			  struct nlattr *data[],
576 			  struct netlink_ext_ack *extack)
577 {
578 	struct ip_tunnel *t = netdev_priv(dev);
579 	__u32 fwmark = t->fwmark;
580 	struct ip_tunnel_parm p;
581 
582 	vti_netlink_parms(data, &p, &fwmark);
583 	return ip_tunnel_changelink(dev, tb, &p, fwmark);
584 }
585 
586 static size_t vti_get_size(const struct net_device *dev)
587 {
588 	return
589 		/* IFLA_VTI_LINK */
590 		nla_total_size(4) +
591 		/* IFLA_VTI_IKEY */
592 		nla_total_size(4) +
593 		/* IFLA_VTI_OKEY */
594 		nla_total_size(4) +
595 		/* IFLA_VTI_LOCAL */
596 		nla_total_size(4) +
597 		/* IFLA_VTI_REMOTE */
598 		nla_total_size(4) +
599 		/* IFLA_VTI_FWMARK */
600 		nla_total_size(4) +
601 		0;
602 }
603 
604 static int vti_fill_info(struct sk_buff *skb, const struct net_device *dev)
605 {
606 	struct ip_tunnel *t = netdev_priv(dev);
607 	struct ip_tunnel_parm *p = &t->parms;
608 
609 	if (nla_put_u32(skb, IFLA_VTI_LINK, p->link) ||
610 	    nla_put_be32(skb, IFLA_VTI_IKEY, p->i_key) ||
611 	    nla_put_be32(skb, IFLA_VTI_OKEY, p->o_key) ||
612 	    nla_put_in_addr(skb, IFLA_VTI_LOCAL, p->iph.saddr) ||
613 	    nla_put_in_addr(skb, IFLA_VTI_REMOTE, p->iph.daddr) ||
614 	    nla_put_u32(skb, IFLA_VTI_FWMARK, t->fwmark))
615 		return -EMSGSIZE;
616 
617 	return 0;
618 }
619 
620 static const struct nla_policy vti_policy[IFLA_VTI_MAX + 1] = {
621 	[IFLA_VTI_LINK]		= { .type = NLA_U32 },
622 	[IFLA_VTI_IKEY]		= { .type = NLA_U32 },
623 	[IFLA_VTI_OKEY]		= { .type = NLA_U32 },
624 	[IFLA_VTI_LOCAL]	= { .len = sizeof_field(struct iphdr, saddr) },
625 	[IFLA_VTI_REMOTE]	= { .len = sizeof_field(struct iphdr, daddr) },
626 	[IFLA_VTI_FWMARK]	= { .type = NLA_U32 },
627 };
628 
629 static struct rtnl_link_ops vti_link_ops __read_mostly = {
630 	.kind		= "vti",
631 	.maxtype	= IFLA_VTI_MAX,
632 	.policy		= vti_policy,
633 	.priv_size	= sizeof(struct ip_tunnel),
634 	.setup		= vti_tunnel_setup,
635 	.validate	= vti_tunnel_validate,
636 	.newlink	= vti_newlink,
637 	.changelink	= vti_changelink,
638 	.dellink        = ip_tunnel_dellink,
639 	.get_size	= vti_get_size,
640 	.fill_info	= vti_fill_info,
641 	.get_link_net	= ip_tunnel_get_link_net,
642 };
643 
644 static int __init vti_init(void)
645 {
646 	const char *msg;
647 	int err;
648 
649 	pr_info("IPv4 over IPsec tunneling driver\n");
650 
651 	msg = "tunnel device";
652 	err = register_pernet_device(&vti_net_ops);
653 	if (err < 0)
654 		goto pernet_dev_failed;
655 
656 	msg = "tunnel protocols";
657 	err = xfrm4_protocol_register(&vti_esp4_protocol, IPPROTO_ESP);
658 	if (err < 0)
659 		goto xfrm_proto_esp_failed;
660 	err = xfrm4_protocol_register(&vti_ah4_protocol, IPPROTO_AH);
661 	if (err < 0)
662 		goto xfrm_proto_ah_failed;
663 	err = xfrm4_protocol_register(&vti_ipcomp4_protocol, IPPROTO_COMP);
664 	if (err < 0)
665 		goto xfrm_proto_comp_failed;
666 
667 #if IS_ENABLED(CONFIG_INET_XFRM_TUNNEL)
668 	msg = "ipip tunnel";
669 	err = xfrm4_tunnel_register(&vti_ipip_handler, AF_INET);
670 	if (err < 0)
671 		goto xfrm_tunnel_ipip_failed;
672 #if IS_ENABLED(CONFIG_IPV6)
673 	err = xfrm4_tunnel_register(&vti_ipip6_handler, AF_INET6);
674 	if (err < 0)
675 		goto xfrm_tunnel_ipip6_failed;
676 #endif
677 #endif
678 
679 	msg = "netlink interface";
680 	err = rtnl_link_register(&vti_link_ops);
681 	if (err < 0)
682 		goto rtnl_link_failed;
683 
684 	return err;
685 
686 rtnl_link_failed:
687 #if IS_ENABLED(CONFIG_INET_XFRM_TUNNEL)
688 #if IS_ENABLED(CONFIG_IPV6)
689 	xfrm4_tunnel_deregister(&vti_ipip6_handler, AF_INET6);
690 xfrm_tunnel_ipip6_failed:
691 #endif
692 	xfrm4_tunnel_deregister(&vti_ipip_handler, AF_INET);
693 xfrm_tunnel_ipip_failed:
694 #endif
695 	xfrm4_protocol_deregister(&vti_ipcomp4_protocol, IPPROTO_COMP);
696 xfrm_proto_comp_failed:
697 	xfrm4_protocol_deregister(&vti_ah4_protocol, IPPROTO_AH);
698 xfrm_proto_ah_failed:
699 	xfrm4_protocol_deregister(&vti_esp4_protocol, IPPROTO_ESP);
700 xfrm_proto_esp_failed:
701 	unregister_pernet_device(&vti_net_ops);
702 pernet_dev_failed:
703 	pr_err("vti init: failed to register %s\n", msg);
704 	return err;
705 }
706 
707 static void __exit vti_fini(void)
708 {
709 	rtnl_link_unregister(&vti_link_ops);
710 #if IS_ENABLED(CONFIG_INET_XFRM_TUNNEL)
711 #if IS_ENABLED(CONFIG_IPV6)
712 	xfrm4_tunnel_deregister(&vti_ipip6_handler, AF_INET6);
713 #endif
714 	xfrm4_tunnel_deregister(&vti_ipip_handler, AF_INET);
715 #endif
716 	xfrm4_protocol_deregister(&vti_ipcomp4_protocol, IPPROTO_COMP);
717 	xfrm4_protocol_deregister(&vti_ah4_protocol, IPPROTO_AH);
718 	xfrm4_protocol_deregister(&vti_esp4_protocol, IPPROTO_ESP);
719 	unregister_pernet_device(&vti_net_ops);
720 }
721 
722 module_init(vti_init);
723 module_exit(vti_fini);
724 MODULE_LICENSE("GPL");
725 MODULE_ALIAS_RTNL_LINK("vti");
726 MODULE_ALIAS_NETDEV("ip_vti0");
727