1/*
2 *	Linux NET3: IP/IP protocol decoder modified to support
3 *		    virtual tunnel interface
4 *
5 *	Authors:
6 *		Saurabh Mohan (saurabh.mohan@vyatta.com) 05/07/2012
7 *
8 *	This program is free software; you can redistribute it and/or
9 *	modify it under the terms of the GNU General Public License
10 *	as published by the Free Software Foundation; either version
11 *	2 of the License, or (at your option) any later version.
12 *
13 */
14
15/*
16   This version of net/ipv4/ip_vti.c is cloned of net/ipv4/ipip.c
17
18   For comments look at net/ipv4/ip_gre.c --ANK
19 */
20
21
22#include <linux/capability.h>
23#include <linux/module.h>
24#include <linux/types.h>
25#include <linux/kernel.h>
26#include <linux/uaccess.h>
27#include <linux/skbuff.h>
28#include <linux/netdevice.h>
29#include <linux/in.h>
30#include <linux/tcp.h>
31#include <linux/udp.h>
32#include <linux/if_arp.h>
33#include <linux/mroute.h>
34#include <linux/init.h>
35#include <linux/netfilter_ipv4.h>
36#include <linux/if_ether.h>
37
38#include <net/sock.h>
39#include <net/ip.h>
40#include <net/icmp.h>
41#include <net/ip_tunnels.h>
42#include <net/inet_ecn.h>
43#include <net/xfrm.h>
44#include <net/net_namespace.h>
45#include <net/netns/generic.h>
46
47#define HASH_SIZE  16
48#define HASH(addr) (((__force u32)addr^((__force u32)addr>>4))&(HASH_SIZE-1))
49
50static struct rtnl_link_ops vti_link_ops __read_mostly;
51
52static int vti_net_id __read_mostly;
53struct vti_net {
54	struct ip_tunnel __rcu *tunnels_r_l[HASH_SIZE];
55	struct ip_tunnel __rcu *tunnels_r[HASH_SIZE];
56	struct ip_tunnel __rcu *tunnels_l[HASH_SIZE];
57	struct ip_tunnel __rcu *tunnels_wc[1];
58	struct ip_tunnel __rcu **tunnels[4];
59
60	struct net_device *fb_tunnel_dev;
61};
62
63static int vti_fb_tunnel_init(struct net_device *dev);
64static int vti_tunnel_init(struct net_device *dev);
65static void vti_tunnel_setup(struct net_device *dev);
66static void vti_dev_free(struct net_device *dev);
67static int vti_tunnel_bind_dev(struct net_device *dev);
68
69#define VTI_XMIT(stats1, stats2) do {				\
70	int err;						\
71	int pkt_len = skb->len;					\
72	err = dst_output(skb);					\
73	if (net_xmit_eval(err) == 0) {				\
74		u64_stats_update_begin(&(stats1)->syncp);	\
75		(stats1)->tx_bytes += pkt_len;			\
76		(stats1)->tx_packets++;				\
77		u64_stats_update_end(&(stats1)->syncp);		\
78	} else {						\
79		(stats2)->tx_errors++;				\
80		(stats2)->tx_aborted_errors++;			\
81	}							\
82} while (0)
83
84
85static struct ip_tunnel *vti_tunnel_lookup(struct net *net,
86					   __be32 remote, __be32 local)
87{
88	unsigned h0 = HASH(remote);
89	unsigned h1 = HASH(local);
90	struct ip_tunnel *t;
91	struct vti_net *ipn = net_generic(net, vti_net_id);
92
93	for_each_ip_tunnel_rcu(t, ipn->tunnels_r_l[h0 ^ h1])
94		if (local == t->parms.iph.saddr &&
95		    remote == t->parms.iph.daddr && (t->dev->flags&IFF_UP))
96			return t;
97	for_each_ip_tunnel_rcu(t, ipn->tunnels_r[h0])
98		if (remote == t->parms.iph.daddr && (t->dev->flags&IFF_UP))
99			return t;
100
101	for_each_ip_tunnel_rcu(t, ipn->tunnels_l[h1])
102		if (local == t->parms.iph.saddr && (t->dev->flags&IFF_UP))
103			return t;
104
105	for_each_ip_tunnel_rcu(t, ipn->tunnels_wc[0])
106		if (t && (t->dev->flags&IFF_UP))
107			return t;
108	return NULL;
109}
110
111static struct ip_tunnel __rcu **__vti_bucket(struct vti_net *ipn,
112					     struct ip_tunnel_parm *parms)
113{
114	__be32 remote = parms->iph.daddr;
115	__be32 local = parms->iph.saddr;
116	unsigned h = 0;
117	int prio = 0;
118
119	if (remote) {
120		prio |= 2;
121		h ^= HASH(remote);
122	}
123	if (local) {
124		prio |= 1;
125		h ^= HASH(local);
126	}
127	return &ipn->tunnels[prio][h];
128}
129
130static inline struct ip_tunnel __rcu **vti_bucket(struct vti_net *ipn,
131						  struct ip_tunnel *t)
132{
133	return __vti_bucket(ipn, &t->parms);
134}
135
136static void vti_tunnel_unlink(struct vti_net *ipn, struct ip_tunnel *t)
137{
138	struct ip_tunnel __rcu **tp;
139	struct ip_tunnel *iter;
140
141	for (tp = vti_bucket(ipn, t);
142	     (iter = rtnl_dereference(*tp)) != NULL;
143	     tp = &iter->next) {
144		if (t == iter) {
145			rcu_assign_pointer(*tp, t->next);
146			break;
147		}
148	}
149}
150
151static void vti_tunnel_link(struct vti_net *ipn, struct ip_tunnel *t)
152{
153	struct ip_tunnel __rcu **tp = vti_bucket(ipn, t);
154
155	rcu_assign_pointer(t->next, rtnl_dereference(*tp));
156	rcu_assign_pointer(*tp, t);
157}
158
159static struct ip_tunnel *vti_tunnel_locate(struct net *net,
160					   struct ip_tunnel_parm *parms,
161					   int create)
162{
163	__be32 remote = parms->iph.daddr;
164	__be32 local = parms->iph.saddr;
165	struct ip_tunnel *t, *nt;
166	struct ip_tunnel __rcu **tp;
167	struct net_device *dev;
168	char name[IFNAMSIZ];
169	struct vti_net *ipn = net_generic(net, vti_net_id);
170
171	for (tp = __vti_bucket(ipn, parms);
172	     (t = rtnl_dereference(*tp)) != NULL;
173	     tp = &t->next) {
174		if (local == t->parms.iph.saddr && remote == t->parms.iph.daddr)
175			return t;
176	}
177	if (!create)
178		return NULL;
179
180	if (parms->name[0])
181		strlcpy(name, parms->name, IFNAMSIZ);
182	else
183		strcpy(name, "vti%d");
184
185	dev = alloc_netdev(sizeof(*t), name, vti_tunnel_setup);
186	if (dev == NULL)
187		return NULL;
188
189	dev_net_set(dev, net);
190
191	nt = netdev_priv(dev);
192	nt->parms = *parms;
193	dev->rtnl_link_ops = &vti_link_ops;
194
195	vti_tunnel_bind_dev(dev);
196
197	if (register_netdevice(dev) < 0)
198		goto failed_free;
199
200	dev_hold(dev);
201	vti_tunnel_link(ipn, nt);
202	return nt;
203
204failed_free:
205	free_netdev(dev);
206	return NULL;
207}
208
209static void vti_tunnel_uninit(struct net_device *dev)
210{
211	struct net *net = dev_net(dev);
212	struct vti_net *ipn = net_generic(net, vti_net_id);
213
214	vti_tunnel_unlink(ipn, netdev_priv(dev));
215	dev_put(dev);
216}
217
218static int vti_err(struct sk_buff *skb, u32 info)
219{
220
221	/* All the routers (except for Linux) return only
222	 * 8 bytes of packet payload. It means, that precise relaying of
223	 * ICMP in the real Internet is absolutely infeasible.
224	 */
225	struct iphdr *iph = (struct iphdr *)skb->data;
226	const int type = icmp_hdr(skb)->type;
227	const int code = icmp_hdr(skb)->code;
228	struct ip_tunnel *t;
229	int err;
230
231	switch (type) {
232	default:
233	case ICMP_PARAMETERPROB:
234		return 0;
235
236	case ICMP_DEST_UNREACH:
237		switch (code) {
238		case ICMP_SR_FAILED:
239		case ICMP_PORT_UNREACH:
240			/* Impossible event. */
241			return 0;
242		default:
243			/* All others are translated to HOST_UNREACH. */
244			break;
245		}
246		break;
247	case ICMP_TIME_EXCEEDED:
248		if (code != ICMP_EXC_TTL)
249			return 0;
250		break;
251	}
252
253	err = -ENOENT;
254
255	t = vti_tunnel_lookup(dev_net(skb->dev), iph->daddr, iph->saddr);
256	if (t == NULL)
257		goto out;
258
259	if (type == ICMP_DEST_UNREACH && code == ICMP_FRAG_NEEDED) {
260		ipv4_update_pmtu(skb, dev_net(skb->dev), info,
261				 t->parms.link, 0, IPPROTO_IPIP, 0);
262		err = 0;
263		goto out;
264	}
265
266	err = 0;
267	if (t->parms.iph.ttl == 0 && type == ICMP_TIME_EXCEEDED)
268		goto out;
269
270	if (time_before(jiffies, t->err_time + IPTUNNEL_ERR_TIMEO))
271		t->err_count++;
272	else
273		t->err_count = 1;
274	t->err_time = jiffies;
275out:
276	return err;
277}
278
279/* We dont digest the packet therefore let the packet pass */
280static int vti_rcv(struct sk_buff *skb)
281{
282	struct ip_tunnel *tunnel;
283	const struct iphdr *iph = ip_hdr(skb);
284
285	tunnel = vti_tunnel_lookup(dev_net(skb->dev), iph->saddr, iph->daddr);
286	if (tunnel != NULL) {
287		struct pcpu_tstats *tstats;
288
289		if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb))
290			return -1;
291
292		tstats = this_cpu_ptr(tunnel->dev->tstats);
293		u64_stats_update_begin(&tstats->syncp);
294		tstats->rx_packets++;
295		tstats->rx_bytes += skb->len;
296		u64_stats_update_end(&tstats->syncp);
297
298		skb->mark = 0;
299		secpath_reset(skb);
300		skb->dev = tunnel->dev;
301		return 1;
302	}
303
304	return -1;
305}
306
307/* This function assumes it is being called from dev_queue_xmit()
308 * and that skb is filled properly by that function.
309 */
310
311static netdev_tx_t vti_tunnel_xmit(struct sk_buff *skb, struct net_device *dev)
312{
313	struct ip_tunnel *tunnel = netdev_priv(dev);
314	struct pcpu_tstats *tstats;
315	struct iphdr  *tiph = &tunnel->parms.iph;
316	u8     tos;
317	struct rtable *rt;		/* Route to the other host */
318	struct net_device *tdev;	/* Device to other host */
319	struct iphdr  *old_iph = ip_hdr(skb);
320	__be32 dst = tiph->daddr;
321	struct flowi4 fl4;
322
323	if (skb->protocol != htons(ETH_P_IP))
324		goto tx_error;
325
326	tos = old_iph->tos;
327
328	memset(&fl4, 0, sizeof(fl4));
329	flowi4_init_output(&fl4, tunnel->parms.link,
330			   be32_to_cpu(tunnel->parms.i_key), RT_TOS(tos),
331			   RT_SCOPE_UNIVERSE,
332			   IPPROTO_IPIP, 0,
333			   dst, tiph->saddr, 0, 0);
334	rt = ip_route_output_key(dev_net(dev), &fl4);
335	if (IS_ERR(rt)) {
336		dev->stats.tx_carrier_errors++;
337		goto tx_error_icmp;
338	}
339	/* if there is no transform then this tunnel is not functional.
340	 * Or if the xfrm is not mode tunnel.
341	 */
342	if (!rt->dst.xfrm ||
343	    rt->dst.xfrm->props.mode != XFRM_MODE_TUNNEL) {
344		dev->stats.tx_carrier_errors++;
345		goto tx_error_icmp;
346	}
347	tdev = rt->dst.dev;
348
349	if (tdev == dev) {
350		ip_rt_put(rt);
351		dev->stats.collisions++;
352		goto tx_error;
353	}
354
355	if (tunnel->err_count > 0) {
356		if (time_before(jiffies,
357				tunnel->err_time + IPTUNNEL_ERR_TIMEO)) {
358			tunnel->err_count--;
359			dst_link_failure(skb);
360		} else
361			tunnel->err_count = 0;
362	}
363
364	memset(IPCB(skb), 0, sizeof(*IPCB(skb)));
365	skb_dst_drop(skb);
366	skb_dst_set(skb, &rt->dst);
367	nf_reset(skb);
368	skb->dev = skb_dst(skb)->dev;
369
370	tstats = this_cpu_ptr(dev->tstats);
371	VTI_XMIT(tstats, &dev->stats);
372	return NETDEV_TX_OK;
373
374tx_error_icmp:
375	dst_link_failure(skb);
376tx_error:
377	dev->stats.tx_errors++;
378	dev_kfree_skb(skb);
379	return NETDEV_TX_OK;
380}
381
382static int vti_tunnel_bind_dev(struct net_device *dev)
383{
384	struct net_device *tdev = NULL;
385	struct ip_tunnel *tunnel;
386	struct iphdr *iph;
387
388	tunnel = netdev_priv(dev);
389	iph = &tunnel->parms.iph;
390
391	if (iph->daddr) {
392		struct rtable *rt;
393		struct flowi4 fl4;
394		memset(&fl4, 0, sizeof(fl4));
395		flowi4_init_output(&fl4, tunnel->parms.link,
396				   be32_to_cpu(tunnel->parms.i_key),
397				   RT_TOS(iph->tos), RT_SCOPE_UNIVERSE,
398				   IPPROTO_IPIP, 0,
399				   iph->daddr, iph->saddr, 0, 0);
400		rt = ip_route_output_key(dev_net(dev), &fl4);
401		if (!IS_ERR(rt)) {
402			tdev = rt->dst.dev;
403			ip_rt_put(rt);
404		}
405		dev->flags |= IFF_POINTOPOINT;
406	}
407
408	if (!tdev && tunnel->parms.link)
409		tdev = __dev_get_by_index(dev_net(dev), tunnel->parms.link);
410
411	if (tdev) {
412		dev->hard_header_len = tdev->hard_header_len +
413				       sizeof(struct iphdr);
414		dev->mtu = tdev->mtu;
415	}
416	dev->iflink = tunnel->parms.link;
417	return dev->mtu;
418}
419
420static int
421vti_tunnel_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
422{
423	int err = 0;
424	struct ip_tunnel_parm p;
425	struct ip_tunnel *t;
426	struct net *net = dev_net(dev);
427	struct vti_net *ipn = net_generic(net, vti_net_id);
428
429	switch (cmd) {
430	case SIOCGETTUNNEL:
431		t = NULL;
432		if (dev == ipn->fb_tunnel_dev) {
433			if (copy_from_user(&p, ifr->ifr_ifru.ifru_data,
434					   sizeof(p))) {
435				err = -EFAULT;
436				break;
437			}
438			t = vti_tunnel_locate(net, &p, 0);
439		}
440		if (t == NULL)
441			t = netdev_priv(dev);
442		memcpy(&p, &t->parms, sizeof(p));
443		p.i_flags |= GRE_KEY | VTI_ISVTI;
444		p.o_flags |= GRE_KEY;
445		if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
446			err = -EFAULT;
447		break;
448
449	case SIOCADDTUNNEL:
450	case SIOCCHGTUNNEL:
451		err = -EPERM;
452		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
453			goto done;
454
455		err = -EFAULT;
456		if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
457			goto done;
458
459		err = -EINVAL;
460		if (p.iph.version != 4 || p.iph.protocol != IPPROTO_IPIP ||
461		    p.iph.ihl != 5)
462			goto done;
463
464		t = vti_tunnel_locate(net, &p, cmd == SIOCADDTUNNEL);
465
466		if (dev != ipn->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) {
467			if (t != NULL) {
468				if (t->dev != dev) {
469					err = -EEXIST;
470					break;
471				}
472			} else {
473				if (((dev->flags&IFF_POINTOPOINT) &&
474				    !p.iph.daddr) ||
475				    (!(dev->flags&IFF_POINTOPOINT) &&
476				    p.iph.daddr)) {
477					err = -EINVAL;
478					break;
479				}
480				t = netdev_priv(dev);
481				vti_tunnel_unlink(ipn, t);
482				synchronize_net();
483				t->parms.iph.saddr = p.iph.saddr;
484				t->parms.iph.daddr = p.iph.daddr;
485				t->parms.i_key = p.i_key;
486				t->parms.o_key = p.o_key;
487				t->parms.iph.protocol = IPPROTO_IPIP;
488				memcpy(dev->dev_addr, &p.iph.saddr, 4);
489				memcpy(dev->broadcast, &p.iph.daddr, 4);
490				vti_tunnel_link(ipn, t);
491				netdev_state_change(dev);
492			}
493		}
494
495		if (t) {
496			err = 0;
497			if (cmd == SIOCCHGTUNNEL) {
498				t->parms.i_key = p.i_key;
499				t->parms.o_key = p.o_key;
500				if (t->parms.link != p.link) {
501					t->parms.link = p.link;
502					vti_tunnel_bind_dev(dev);
503					netdev_state_change(dev);
504				}
505			}
506			p.i_flags |= GRE_KEY | VTI_ISVTI;
507			p.o_flags |= GRE_KEY;
508			if (copy_to_user(ifr->ifr_ifru.ifru_data, &t->parms,
509					 sizeof(p)))
510				err = -EFAULT;
511		} else
512			err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
513		break;
514
515	case SIOCDELTUNNEL:
516		err = -EPERM;
517		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
518			goto done;
519
520		if (dev == ipn->fb_tunnel_dev) {
521			err = -EFAULT;
522			if (copy_from_user(&p, ifr->ifr_ifru.ifru_data,
523					   sizeof(p)))
524				goto done;
525			err = -ENOENT;
526
527			t = vti_tunnel_locate(net, &p, 0);
528			if (t == NULL)
529				goto done;
530			err = -EPERM;
531			if (t->dev == ipn->fb_tunnel_dev)
532				goto done;
533			dev = t->dev;
534		}
535		unregister_netdevice(dev);
536		err = 0;
537		break;
538
539	default:
540		err = -EINVAL;
541	}
542
543done:
544	return err;
545}
546
547static int vti_tunnel_change_mtu(struct net_device *dev, int new_mtu)
548{
549	if (new_mtu < 68 || new_mtu > 0xFFF8)
550		return -EINVAL;
551	dev->mtu = new_mtu;
552	return 0;
553}
554
555static const struct net_device_ops vti_netdev_ops = {
556	.ndo_init	= vti_tunnel_init,
557	.ndo_uninit	= vti_tunnel_uninit,
558	.ndo_start_xmit	= vti_tunnel_xmit,
559	.ndo_do_ioctl	= vti_tunnel_ioctl,
560	.ndo_change_mtu	= vti_tunnel_change_mtu,
561	.ndo_get_stats64 = ip_tunnel_get_stats64,
562};
563
564static void vti_dev_free(struct net_device *dev)
565{
566	free_percpu(dev->tstats);
567	free_netdev(dev);
568}
569
570static void vti_tunnel_setup(struct net_device *dev)
571{
572	dev->netdev_ops		= &vti_netdev_ops;
573	dev->destructor		= vti_dev_free;
574
575	dev->type		= ARPHRD_TUNNEL;
576	dev->hard_header_len	= LL_MAX_HEADER + sizeof(struct iphdr);
577	dev->mtu		= ETH_DATA_LEN;
578	dev->flags		= IFF_NOARP;
579	dev->iflink		= 0;
580	dev->addr_len		= 4;
581	dev->features		|= NETIF_F_NETNS_LOCAL;
582	dev->features		|= NETIF_F_LLTX;
583	dev->priv_flags		&= ~IFF_XMIT_DST_RELEASE;
584}
585
586static int vti_tunnel_init(struct net_device *dev)
587{
588	struct ip_tunnel *tunnel = netdev_priv(dev);
589
590	tunnel->dev = dev;
591	strcpy(tunnel->parms.name, dev->name);
592
593	memcpy(dev->dev_addr, &tunnel->parms.iph.saddr, 4);
594	memcpy(dev->broadcast, &tunnel->parms.iph.daddr, 4);
595
596	dev->tstats = alloc_percpu(struct pcpu_tstats);
597	if (!dev->tstats)
598		return -ENOMEM;
599
600	return 0;
601}
602
603static int __net_init vti_fb_tunnel_init(struct net_device *dev)
604{
605	struct ip_tunnel *tunnel = netdev_priv(dev);
606	struct iphdr *iph = &tunnel->parms.iph;
607	struct vti_net *ipn = net_generic(dev_net(dev), vti_net_id);
608
609	tunnel->dev = dev;
610	strcpy(tunnel->parms.name, dev->name);
611
612	iph->version		= 4;
613	iph->protocol		= IPPROTO_IPIP;
614	iph->ihl		= 5;
615
616	dev->tstats = alloc_percpu(struct pcpu_tstats);
617	if (!dev->tstats)
618		return -ENOMEM;
619
620	dev_hold(dev);
621	rcu_assign_pointer(ipn->tunnels_wc[0], tunnel);
622	return 0;
623}
624
625static struct xfrm_tunnel vti_handler __read_mostly = {
626	.handler	=	vti_rcv,
627	.err_handler	=	vti_err,
628	.priority	=	1,
629};
630
631static void vti_destroy_tunnels(struct vti_net *ipn, struct list_head *head)
632{
633	int prio;
634
635	for (prio = 1; prio < 4; prio++) {
636		int h;
637		for (h = 0; h < HASH_SIZE; h++) {
638			struct ip_tunnel *t;
639
640			t = rtnl_dereference(ipn->tunnels[prio][h]);
641			while (t != NULL) {
642				unregister_netdevice_queue(t->dev, head);
643				t = rtnl_dereference(t->next);
644			}
645		}
646	}
647}
648
649static int __net_init vti_init_net(struct net *net)
650{
651	int err;
652	struct vti_net *ipn = net_generic(net, vti_net_id);
653
654	ipn->tunnels[0] = ipn->tunnels_wc;
655	ipn->tunnels[1] = ipn->tunnels_l;
656	ipn->tunnels[2] = ipn->tunnels_r;
657	ipn->tunnels[3] = ipn->tunnels_r_l;
658
659	ipn->fb_tunnel_dev = alloc_netdev(sizeof(struct ip_tunnel),
660					  "ip_vti0",
661					  vti_tunnel_setup);
662	if (!ipn->fb_tunnel_dev) {
663		err = -ENOMEM;
664		goto err_alloc_dev;
665	}
666	dev_net_set(ipn->fb_tunnel_dev, net);
667
668	err = vti_fb_tunnel_init(ipn->fb_tunnel_dev);
669	if (err)
670		goto err_reg_dev;
671	ipn->fb_tunnel_dev->rtnl_link_ops = &vti_link_ops;
672
673	err = register_netdev(ipn->fb_tunnel_dev);
674	if (err)
675		goto err_reg_dev;
676	return 0;
677
678err_reg_dev:
679	vti_dev_free(ipn->fb_tunnel_dev);
680err_alloc_dev:
681	/* nothing */
682	return err;
683}
684
685static void __net_exit vti_exit_net(struct net *net)
686{
687	struct vti_net *ipn = net_generic(net, vti_net_id);
688	LIST_HEAD(list);
689
690	rtnl_lock();
691	vti_destroy_tunnels(ipn, &list);
692	unregister_netdevice_many(&list);
693	rtnl_unlock();
694}
695
696static struct pernet_operations vti_net_ops = {
697	.init = vti_init_net,
698	.exit = vti_exit_net,
699	.id   = &vti_net_id,
700	.size = sizeof(struct vti_net),
701};
702
703static int vti_tunnel_validate(struct nlattr *tb[], struct nlattr *data[])
704{
705	return 0;
706}
707
708static void vti_netlink_parms(struct nlattr *data[],
709			      struct ip_tunnel_parm *parms)
710{
711	memset(parms, 0, sizeof(*parms));
712
713	parms->iph.protocol = IPPROTO_IPIP;
714
715	if (!data)
716		return;
717
718	if (data[IFLA_VTI_LINK])
719		parms->link = nla_get_u32(data[IFLA_VTI_LINK]);
720
721	if (data[IFLA_VTI_IKEY])
722		parms->i_key = nla_get_be32(data[IFLA_VTI_IKEY]);
723
724	if (data[IFLA_VTI_OKEY])
725		parms->o_key = nla_get_be32(data[IFLA_VTI_OKEY]);
726
727	if (data[IFLA_VTI_LOCAL])
728		parms->iph.saddr = nla_get_be32(data[IFLA_VTI_LOCAL]);
729
730	if (data[IFLA_VTI_REMOTE])
731		parms->iph.daddr = nla_get_be32(data[IFLA_VTI_REMOTE]);
732
733}
734
735static int vti_newlink(struct net *src_net, struct net_device *dev,
736		       struct nlattr *tb[], struct nlattr *data[])
737{
738	struct ip_tunnel *nt;
739	struct net *net = dev_net(dev);
740	struct vti_net *ipn = net_generic(net, vti_net_id);
741	int mtu;
742	int err;
743
744	nt = netdev_priv(dev);
745	vti_netlink_parms(data, &nt->parms);
746
747	if (vti_tunnel_locate(net, &nt->parms, 0))
748		return -EEXIST;
749
750	mtu = vti_tunnel_bind_dev(dev);
751	if (!tb[IFLA_MTU])
752		dev->mtu = mtu;
753
754	err = register_netdevice(dev);
755	if (err)
756		goto out;
757
758	dev_hold(dev);
759	vti_tunnel_link(ipn, nt);
760
761out:
762	return err;
763}
764
765static int vti_changelink(struct net_device *dev, struct nlattr *tb[],
766			  struct nlattr *data[])
767{
768	struct ip_tunnel *t, *nt;
769	struct net *net = dev_net(dev);
770	struct vti_net *ipn = net_generic(net, vti_net_id);
771	struct ip_tunnel_parm p;
772	int mtu;
773
774	if (dev == ipn->fb_tunnel_dev)
775		return -EINVAL;
776
777	nt = netdev_priv(dev);
778	vti_netlink_parms(data, &p);
779
780	t = vti_tunnel_locate(net, &p, 0);
781
782	if (t) {
783		if (t->dev != dev)
784			return -EEXIST;
785	} else {
786		t = nt;
787
788		vti_tunnel_unlink(ipn, t);
789		t->parms.iph.saddr = p.iph.saddr;
790		t->parms.iph.daddr = p.iph.daddr;
791		t->parms.i_key = p.i_key;
792		t->parms.o_key = p.o_key;
793		if (dev->type != ARPHRD_ETHER) {
794			memcpy(dev->dev_addr, &p.iph.saddr, 4);
795			memcpy(dev->broadcast, &p.iph.daddr, 4);
796		}
797		vti_tunnel_link(ipn, t);
798		netdev_state_change(dev);
799	}
800
801	if (t->parms.link != p.link) {
802		t->parms.link = p.link;
803		mtu = vti_tunnel_bind_dev(dev);
804		if (!tb[IFLA_MTU])
805			dev->mtu = mtu;
806		netdev_state_change(dev);
807	}
808
809	return 0;
810}
811
812static size_t vti_get_size(const struct net_device *dev)
813{
814	return
815		/* IFLA_VTI_LINK */
816		nla_total_size(4) +
817		/* IFLA_VTI_IKEY */
818		nla_total_size(4) +
819		/* IFLA_VTI_OKEY */
820		nla_total_size(4) +
821		/* IFLA_VTI_LOCAL */
822		nla_total_size(4) +
823		/* IFLA_VTI_REMOTE */
824		nla_total_size(4) +
825		0;
826}
827
828static int vti_fill_info(struct sk_buff *skb, const struct net_device *dev)
829{
830	struct ip_tunnel *t = netdev_priv(dev);
831	struct ip_tunnel_parm *p = &t->parms;
832
833	nla_put_u32(skb, IFLA_VTI_LINK, p->link);
834	nla_put_be32(skb, IFLA_VTI_IKEY, p->i_key);
835	nla_put_be32(skb, IFLA_VTI_OKEY, p->o_key);
836	nla_put_be32(skb, IFLA_VTI_LOCAL, p->iph.saddr);
837	nla_put_be32(skb, IFLA_VTI_REMOTE, p->iph.daddr);
838
839	return 0;
840}
841
842static const struct nla_policy vti_policy[IFLA_VTI_MAX + 1] = {
843	[IFLA_VTI_LINK]		= { .type = NLA_U32 },
844	[IFLA_VTI_IKEY]		= { .type = NLA_U32 },
845	[IFLA_VTI_OKEY]		= { .type = NLA_U32 },
846	[IFLA_VTI_LOCAL]	= { .len = FIELD_SIZEOF(struct iphdr, saddr) },
847	[IFLA_VTI_REMOTE]	= { .len = FIELD_SIZEOF(struct iphdr, daddr) },
848};
849
850static struct rtnl_link_ops vti_link_ops __read_mostly = {
851	.kind		= "vti",
852	.maxtype	= IFLA_VTI_MAX,
853	.policy		= vti_policy,
854	.priv_size	= sizeof(struct ip_tunnel),
855	.setup		= vti_tunnel_setup,
856	.validate	= vti_tunnel_validate,
857	.newlink	= vti_newlink,
858	.changelink	= vti_changelink,
859	.get_size	= vti_get_size,
860	.fill_info	= vti_fill_info,
861};
862
863static int __init vti_init(void)
864{
865	int err;
866
867	pr_info("IPv4 over IPSec tunneling driver\n");
868
869	err = register_pernet_device(&vti_net_ops);
870	if (err < 0)
871		return err;
872	err = xfrm4_mode_tunnel_input_register(&vti_handler);
873	if (err < 0) {
874		unregister_pernet_device(&vti_net_ops);
875		pr_info(KERN_INFO "vti init: can't register tunnel\n");
876	}
877
878	err = rtnl_link_register(&vti_link_ops);
879	if (err < 0)
880		goto rtnl_link_failed;
881
882	return err;
883
884rtnl_link_failed:
885	xfrm4_mode_tunnel_input_deregister(&vti_handler);
886	unregister_pernet_device(&vti_net_ops);
887	return err;
888}
889
890static void __exit vti_fini(void)
891{
892	rtnl_link_unregister(&vti_link_ops);
893	if (xfrm4_mode_tunnel_input_deregister(&vti_handler))
894		pr_info("vti close: can't deregister tunnel\n");
895
896	unregister_pernet_device(&vti_net_ops);
897}
898
899module_init(vti_init);
900module_exit(vti_fini);
901MODULE_LICENSE("GPL");
902MODULE_ALIAS_RTNL_LINK("vti");
903MODULE_ALIAS_NETDEV("ip_vti0");
904