Merge remote-tracking branch 'lsk/v3.10/topic/big.LITTLE' into linux-linaro-lsk
[firefly-linux-kernel-4.4.55.git] / net / ipv4 / ip_vti.c
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
50 static struct rtnl_link_ops vti_link_ops __read_mostly;
51
52 static int vti_net_id __read_mostly;
53 struct 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
63 static int vti_fb_tunnel_init(struct net_device *dev);
64 static int vti_tunnel_init(struct net_device *dev);
65 static void vti_tunnel_setup(struct net_device *dev);
66 static void vti_dev_free(struct net_device *dev);
67 static 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
85 static 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
111 static 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
130 static 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
136 static 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
151 static 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
159 static 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
204 failed_free:
205         free_netdev(dev);
206         return NULL;
207 }
208
209 static 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
218 static 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;
275 out:
276         return err;
277 }
278
279 /* We dont digest the packet therefore let the packet pass */
280 static 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                 u32 oldmark = skb->mark;
289                 int ret;
290
291
292                 /* temporarily mark the skb with the tunnel o_key, to
293                  * only match policies with this mark.
294                  */
295                 skb->mark = be32_to_cpu(tunnel->parms.o_key);
296                 ret = xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb);
297                 skb->mark = oldmark;
298                 if (!ret)
299                         return -1;
300
301                 tstats = this_cpu_ptr(tunnel->dev->tstats);
302                 u64_stats_update_begin(&tstats->syncp);
303                 tstats->rx_packets++;
304                 tstats->rx_bytes += skb->len;
305                 u64_stats_update_end(&tstats->syncp);
306
307                 secpath_reset(skb);
308                 skb->dev = tunnel->dev;
309                 return 1;
310         }
311
312         return -1;
313 }
314
315 /* This function assumes it is being called from dev_queue_xmit()
316  * and that skb is filled properly by that function.
317  */
318
319 static netdev_tx_t vti_tunnel_xmit(struct sk_buff *skb, struct net_device *dev)
320 {
321         struct ip_tunnel *tunnel = netdev_priv(dev);
322         struct pcpu_tstats *tstats;
323         struct iphdr  *tiph = &tunnel->parms.iph;
324         u8     tos;
325         struct rtable *rt;              /* Route to the other host */
326         struct net_device *tdev;        /* Device to other host */
327         struct iphdr  *old_iph = ip_hdr(skb);
328         __be32 dst = tiph->daddr;
329         struct flowi4 fl4;
330
331         if (skb->protocol != htons(ETH_P_IP))
332                 goto tx_error;
333
334         tos = old_iph->tos;
335
336         memset(&fl4, 0, sizeof(fl4));
337         flowi4_init_output(&fl4, tunnel->parms.link,
338                            be32_to_cpu(tunnel->parms.o_key), RT_TOS(tos),
339                            RT_SCOPE_UNIVERSE,
340                            IPPROTO_IPIP, 0,
341                            dst, tiph->saddr, 0, 0);
342         rt = ip_route_output_key(dev_net(dev), &fl4);
343         if (IS_ERR(rt)) {
344                 dev->stats.tx_carrier_errors++;
345                 goto tx_error_icmp;
346         }
347         /* if there is no transform then this tunnel is not functional.
348          * Or if the xfrm is not mode tunnel.
349          */
350         if (!rt->dst.xfrm ||
351             rt->dst.xfrm->props.mode != XFRM_MODE_TUNNEL) {
352                 dev->stats.tx_carrier_errors++;
353                 goto tx_error_icmp;
354         }
355         tdev = rt->dst.dev;
356
357         if (tdev == dev) {
358                 ip_rt_put(rt);
359                 dev->stats.collisions++;
360                 goto tx_error;
361         }
362
363         if (tunnel->err_count > 0) {
364                 if (time_before(jiffies,
365                                 tunnel->err_time + IPTUNNEL_ERR_TIMEO)) {
366                         tunnel->err_count--;
367                         dst_link_failure(skb);
368                 } else
369                         tunnel->err_count = 0;
370         }
371
372         memset(IPCB(skb), 0, sizeof(*IPCB(skb)));
373         skb_dst_drop(skb);
374         skb_dst_set(skb, &rt->dst);
375         nf_reset(skb);
376         skb->dev = skb_dst(skb)->dev;
377
378         tstats = this_cpu_ptr(dev->tstats);
379         VTI_XMIT(tstats, &dev->stats);
380         return NETDEV_TX_OK;
381
382 tx_error_icmp:
383         dst_link_failure(skb);
384 tx_error:
385         dev->stats.tx_errors++;
386         dev_kfree_skb(skb);
387         return NETDEV_TX_OK;
388 }
389
390 static int vti_tunnel_bind_dev(struct net_device *dev)
391 {
392         struct net_device *tdev = NULL;
393         struct ip_tunnel *tunnel;
394         struct iphdr *iph;
395
396         tunnel = netdev_priv(dev);
397         iph = &tunnel->parms.iph;
398
399         if (iph->daddr) {
400                 struct rtable *rt;
401                 struct flowi4 fl4;
402                 memset(&fl4, 0, sizeof(fl4));
403                 flowi4_init_output(&fl4, tunnel->parms.link,
404                                    be32_to_cpu(tunnel->parms.i_key),
405                                    RT_TOS(iph->tos), RT_SCOPE_UNIVERSE,
406                                    IPPROTO_IPIP, 0,
407                                    iph->daddr, iph->saddr, 0, 0);
408                 rt = ip_route_output_key(dev_net(dev), &fl4);
409                 if (!IS_ERR(rt)) {
410                         tdev = rt->dst.dev;
411                         ip_rt_put(rt);
412                 }
413                 dev->flags |= IFF_POINTOPOINT;
414         }
415
416         if (!tdev && tunnel->parms.link)
417                 tdev = __dev_get_by_index(dev_net(dev), tunnel->parms.link);
418
419         if (tdev) {
420                 dev->hard_header_len = tdev->hard_header_len +
421                                        sizeof(struct iphdr);
422                 dev->mtu = tdev->mtu;
423         }
424         dev->iflink = tunnel->parms.link;
425         return dev->mtu;
426 }
427
428 static int
429 vti_tunnel_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
430 {
431         int err = 0;
432         struct ip_tunnel_parm p;
433         struct ip_tunnel *t;
434         struct net *net = dev_net(dev);
435         struct vti_net *ipn = net_generic(net, vti_net_id);
436
437         switch (cmd) {
438         case SIOCGETTUNNEL:
439                 t = NULL;
440                 if (dev == ipn->fb_tunnel_dev) {
441                         if (copy_from_user(&p, ifr->ifr_ifru.ifru_data,
442                                            sizeof(p))) {
443                                 err = -EFAULT;
444                                 break;
445                         }
446                         t = vti_tunnel_locate(net, &p, 0);
447                 }
448                 if (t == NULL)
449                         t = netdev_priv(dev);
450                 memcpy(&p, &t->parms, sizeof(p));
451                 p.i_flags |= GRE_KEY | VTI_ISVTI;
452                 p.o_flags |= GRE_KEY;
453                 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
454                         err = -EFAULT;
455                 break;
456
457         case SIOCADDTUNNEL:
458         case SIOCCHGTUNNEL:
459                 err = -EPERM;
460                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
461                         goto done;
462
463                 err = -EFAULT;
464                 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
465                         goto done;
466
467                 err = -EINVAL;
468                 if (p.iph.version != 4 || p.iph.protocol != IPPROTO_IPIP ||
469                     p.iph.ihl != 5)
470                         goto done;
471
472                 t = vti_tunnel_locate(net, &p, cmd == SIOCADDTUNNEL);
473
474                 if (dev != ipn->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) {
475                         if (t != NULL) {
476                                 if (t->dev != dev) {
477                                         err = -EEXIST;
478                                         break;
479                                 }
480                         } else {
481                                 if (((dev->flags&IFF_POINTOPOINT) &&
482                                     !p.iph.daddr) ||
483                                     (!(dev->flags&IFF_POINTOPOINT) &&
484                                     p.iph.daddr)) {
485                                         err = -EINVAL;
486                                         break;
487                                 }
488                                 t = netdev_priv(dev);
489                                 vti_tunnel_unlink(ipn, t);
490                                 synchronize_net();
491                                 t->parms.iph.saddr = p.iph.saddr;
492                                 t->parms.iph.daddr = p.iph.daddr;
493                                 t->parms.i_key = p.i_key;
494                                 t->parms.o_key = p.o_key;
495                                 t->parms.iph.protocol = IPPROTO_IPIP;
496                                 memcpy(dev->dev_addr, &p.iph.saddr, 4);
497                                 memcpy(dev->broadcast, &p.iph.daddr, 4);
498                                 vti_tunnel_link(ipn, t);
499                                 netdev_state_change(dev);
500                         }
501                 }
502
503                 if (t) {
504                         err = 0;
505                         if (cmd == SIOCCHGTUNNEL) {
506                                 t->parms.i_key = p.i_key;
507                                 t->parms.o_key = p.o_key;
508                                 if (t->parms.link != p.link) {
509                                         t->parms.link = p.link;
510                                         vti_tunnel_bind_dev(dev);
511                                         netdev_state_change(dev);
512                                 }
513                         }
514                         p.i_flags |= GRE_KEY | VTI_ISVTI;
515                         p.o_flags |= GRE_KEY;
516                         if (copy_to_user(ifr->ifr_ifru.ifru_data, &t->parms,
517                                          sizeof(p)))
518                                 err = -EFAULT;
519                 } else
520                         err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
521                 break;
522
523         case SIOCDELTUNNEL:
524                 err = -EPERM;
525                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
526                         goto done;
527
528                 if (dev == ipn->fb_tunnel_dev) {
529                         err = -EFAULT;
530                         if (copy_from_user(&p, ifr->ifr_ifru.ifru_data,
531                                            sizeof(p)))
532                                 goto done;
533                         err = -ENOENT;
534
535                         t = vti_tunnel_locate(net, &p, 0);
536                         if (t == NULL)
537                                 goto done;
538                         err = -EPERM;
539                         if (t->dev == ipn->fb_tunnel_dev)
540                                 goto done;
541                         dev = t->dev;
542                 }
543                 unregister_netdevice(dev);
544                 err = 0;
545                 break;
546
547         default:
548                 err = -EINVAL;
549         }
550
551 done:
552         return err;
553 }
554
555 static int vti_tunnel_change_mtu(struct net_device *dev, int new_mtu)
556 {
557         if (new_mtu < 68 || new_mtu > 0xFFF8)
558                 return -EINVAL;
559         dev->mtu = new_mtu;
560         return 0;
561 }
562
563 static const struct net_device_ops vti_netdev_ops = {
564         .ndo_init       = vti_tunnel_init,
565         .ndo_uninit     = vti_tunnel_uninit,
566         .ndo_start_xmit = vti_tunnel_xmit,
567         .ndo_do_ioctl   = vti_tunnel_ioctl,
568         .ndo_change_mtu = vti_tunnel_change_mtu,
569         .ndo_get_stats64 = ip_tunnel_get_stats64,
570 };
571
572 static void vti_dev_free(struct net_device *dev)
573 {
574         free_percpu(dev->tstats);
575         free_netdev(dev);
576 }
577
578 static void vti_tunnel_setup(struct net_device *dev)
579 {
580         dev->netdev_ops         = &vti_netdev_ops;
581         dev->destructor         = vti_dev_free;
582
583         dev->type               = ARPHRD_TUNNEL;
584         dev->hard_header_len    = LL_MAX_HEADER + sizeof(struct iphdr);
585         dev->mtu                = ETH_DATA_LEN;
586         dev->flags              = IFF_NOARP;
587         dev->iflink             = 0;
588         dev->addr_len           = 4;
589         dev->features           |= NETIF_F_NETNS_LOCAL;
590         dev->features           |= NETIF_F_LLTX;
591         dev->priv_flags         &= ~IFF_XMIT_DST_RELEASE;
592 }
593
594 static int vti_tunnel_init(struct net_device *dev)
595 {
596         struct ip_tunnel *tunnel = netdev_priv(dev);
597
598         tunnel->dev = dev;
599         strcpy(tunnel->parms.name, dev->name);
600
601         memcpy(dev->dev_addr, &tunnel->parms.iph.saddr, 4);
602         memcpy(dev->broadcast, &tunnel->parms.iph.daddr, 4);
603
604         dev->tstats = alloc_percpu(struct pcpu_tstats);
605         if (!dev->tstats)
606                 return -ENOMEM;
607
608         return 0;
609 }
610
611 static int __net_init vti_fb_tunnel_init(struct net_device *dev)
612 {
613         struct ip_tunnel *tunnel = netdev_priv(dev);
614         struct iphdr *iph = &tunnel->parms.iph;
615         struct vti_net *ipn = net_generic(dev_net(dev), vti_net_id);
616
617         iph->version            = 4;
618         iph->protocol           = IPPROTO_IPIP;
619         iph->ihl                = 5;
620
621         dev_hold(dev);
622         rcu_assign_pointer(ipn->tunnels_wc[0], tunnel);
623         return 0;
624 }
625
626 static struct xfrm_tunnel vti_handler __read_mostly = {
627         .handler        =       vti_rcv,
628         .err_handler    =       vti_err,
629         .priority       =       1,
630 };
631
632 static void vti_destroy_tunnels(struct vti_net *ipn, struct list_head *head)
633 {
634         int prio;
635
636         for (prio = 1; prio < 4; prio++) {
637                 int h;
638                 for (h = 0; h < HASH_SIZE; h++) {
639                         struct ip_tunnel *t;
640
641                         t = rtnl_dereference(ipn->tunnels[prio][h]);
642                         while (t != NULL) {
643                                 unregister_netdevice_queue(t->dev, head);
644                                 t = rtnl_dereference(t->next);
645                         }
646                 }
647         }
648 }
649
650 static int __net_init vti_init_net(struct net *net)
651 {
652         int err;
653         struct vti_net *ipn = net_generic(net, vti_net_id);
654
655         ipn->tunnels[0] = ipn->tunnels_wc;
656         ipn->tunnels[1] = ipn->tunnels_l;
657         ipn->tunnels[2] = ipn->tunnels_r;
658         ipn->tunnels[3] = ipn->tunnels_r_l;
659
660         ipn->fb_tunnel_dev = alloc_netdev(sizeof(struct ip_tunnel),
661                                           "ip_vti0",
662                                           vti_tunnel_setup);
663         if (!ipn->fb_tunnel_dev) {
664                 err = -ENOMEM;
665                 goto err_alloc_dev;
666         }
667         dev_net_set(ipn->fb_tunnel_dev, net);
668
669         err = vti_fb_tunnel_init(ipn->fb_tunnel_dev);
670         if (err)
671                 goto err_reg_dev;
672         ipn->fb_tunnel_dev->rtnl_link_ops = &vti_link_ops;
673
674         err = register_netdev(ipn->fb_tunnel_dev);
675         if (err)
676                 goto err_reg_dev;
677         return 0;
678
679 err_reg_dev:
680         vti_dev_free(ipn->fb_tunnel_dev);
681 err_alloc_dev:
682         /* nothing */
683         return err;
684 }
685
686 static void __net_exit vti_exit_net(struct net *net)
687 {
688         struct vti_net *ipn = net_generic(net, vti_net_id);
689         LIST_HEAD(list);
690
691         rtnl_lock();
692         vti_destroy_tunnels(ipn, &list);
693         unregister_netdevice_many(&list);
694         rtnl_unlock();
695 }
696
697 static struct pernet_operations vti_net_ops = {
698         .init = vti_init_net,
699         .exit = vti_exit_net,
700         .id   = &vti_net_id,
701         .size = sizeof(struct vti_net),
702 };
703
704 static int vti_tunnel_validate(struct nlattr *tb[], struct nlattr *data[])
705 {
706         return 0;
707 }
708
709 static void vti_netlink_parms(struct nlattr *data[],
710                               struct ip_tunnel_parm *parms)
711 {
712         memset(parms, 0, sizeof(*parms));
713
714         parms->iph.protocol = IPPROTO_IPIP;
715
716         if (!data)
717                 return;
718
719         if (data[IFLA_VTI_LINK])
720                 parms->link = nla_get_u32(data[IFLA_VTI_LINK]);
721
722         if (data[IFLA_VTI_IKEY])
723                 parms->i_key = nla_get_be32(data[IFLA_VTI_IKEY]);
724
725         if (data[IFLA_VTI_OKEY])
726                 parms->o_key = nla_get_be32(data[IFLA_VTI_OKEY]);
727
728         if (data[IFLA_VTI_LOCAL])
729                 parms->iph.saddr = nla_get_be32(data[IFLA_VTI_LOCAL]);
730
731         if (data[IFLA_VTI_REMOTE])
732                 parms->iph.daddr = nla_get_be32(data[IFLA_VTI_REMOTE]);
733
734 }
735
736 static int vti_newlink(struct net *src_net, struct net_device *dev,
737                        struct nlattr *tb[], struct nlattr *data[])
738 {
739         struct ip_tunnel *nt;
740         struct net *net = dev_net(dev);
741         struct vti_net *ipn = net_generic(net, vti_net_id);
742         int mtu;
743         int err;
744
745         nt = netdev_priv(dev);
746         vti_netlink_parms(data, &nt->parms);
747
748         if (vti_tunnel_locate(net, &nt->parms, 0))
749                 return -EEXIST;
750
751         mtu = vti_tunnel_bind_dev(dev);
752         if (!tb[IFLA_MTU])
753                 dev->mtu = mtu;
754
755         err = register_netdevice(dev);
756         if (err)
757                 goto out;
758
759         dev_hold(dev);
760         vti_tunnel_link(ipn, nt);
761
762 out:
763         return err;
764 }
765
766 static int vti_changelink(struct net_device *dev, struct nlattr *tb[],
767                           struct nlattr *data[])
768 {
769         struct ip_tunnel *t, *nt;
770         struct net *net = dev_net(dev);
771         struct vti_net *ipn = net_generic(net, vti_net_id);
772         struct ip_tunnel_parm p;
773         int mtu;
774
775         if (dev == ipn->fb_tunnel_dev)
776                 return -EINVAL;
777
778         nt = netdev_priv(dev);
779         vti_netlink_parms(data, &p);
780
781         t = vti_tunnel_locate(net, &p, 0);
782
783         if (t) {
784                 if (t->dev != dev)
785                         return -EEXIST;
786         } else {
787                 t = nt;
788
789                 vti_tunnel_unlink(ipn, t);
790                 t->parms.iph.saddr = p.iph.saddr;
791                 t->parms.iph.daddr = p.iph.daddr;
792                 t->parms.i_key = p.i_key;
793                 t->parms.o_key = p.o_key;
794                 if (dev->type != ARPHRD_ETHER) {
795                         memcpy(dev->dev_addr, &p.iph.saddr, 4);
796                         memcpy(dev->broadcast, &p.iph.daddr, 4);
797                 }
798                 vti_tunnel_link(ipn, t);
799                 netdev_state_change(dev);
800         }
801
802         if (t->parms.link != p.link) {
803                 t->parms.link = p.link;
804                 mtu = vti_tunnel_bind_dev(dev);
805                 if (!tb[IFLA_MTU])
806                         dev->mtu = mtu;
807                 netdev_state_change(dev);
808         }
809
810         return 0;
811 }
812
813 static size_t vti_get_size(const struct net_device *dev)
814 {
815         return
816                 /* IFLA_VTI_LINK */
817                 nla_total_size(4) +
818                 /* IFLA_VTI_IKEY */
819                 nla_total_size(4) +
820                 /* IFLA_VTI_OKEY */
821                 nla_total_size(4) +
822                 /* IFLA_VTI_LOCAL */
823                 nla_total_size(4) +
824                 /* IFLA_VTI_REMOTE */
825                 nla_total_size(4) +
826                 0;
827 }
828
829 static int vti_fill_info(struct sk_buff *skb, const struct net_device *dev)
830 {
831         struct ip_tunnel *t = netdev_priv(dev);
832         struct ip_tunnel_parm *p = &t->parms;
833
834         nla_put_u32(skb, IFLA_VTI_LINK, p->link);
835         nla_put_be32(skb, IFLA_VTI_IKEY, p->i_key);
836         nla_put_be32(skb, IFLA_VTI_OKEY, p->o_key);
837         nla_put_be32(skb, IFLA_VTI_LOCAL, p->iph.saddr);
838         nla_put_be32(skb, IFLA_VTI_REMOTE, p->iph.daddr);
839
840         return 0;
841 }
842
843 static const struct nla_policy vti_policy[IFLA_VTI_MAX + 1] = {
844         [IFLA_VTI_LINK]         = { .type = NLA_U32 },
845         [IFLA_VTI_IKEY]         = { .type = NLA_U32 },
846         [IFLA_VTI_OKEY]         = { .type = NLA_U32 },
847         [IFLA_VTI_LOCAL]        = { .len = FIELD_SIZEOF(struct iphdr, saddr) },
848         [IFLA_VTI_REMOTE]       = { .len = FIELD_SIZEOF(struct iphdr, daddr) },
849 };
850
851 static struct rtnl_link_ops vti_link_ops __read_mostly = {
852         .kind           = "vti",
853         .maxtype        = IFLA_VTI_MAX,
854         .policy         = vti_policy,
855         .priv_size      = sizeof(struct ip_tunnel),
856         .setup          = vti_tunnel_setup,
857         .validate       = vti_tunnel_validate,
858         .newlink        = vti_newlink,
859         .changelink     = vti_changelink,
860         .get_size       = vti_get_size,
861         .fill_info      = vti_fill_info,
862 };
863
864 static int __init vti_init(void)
865 {
866         int err;
867
868         pr_info("IPv4 over IPSec tunneling driver\n");
869
870         err = register_pernet_device(&vti_net_ops);
871         if (err < 0)
872                 return err;
873         err = xfrm4_mode_tunnel_input_register(&vti_handler);
874         if (err < 0) {
875                 unregister_pernet_device(&vti_net_ops);
876                 pr_info(KERN_INFO "vti init: can't register tunnel\n");
877         }
878
879         err = rtnl_link_register(&vti_link_ops);
880         if (err < 0)
881                 goto rtnl_link_failed;
882
883         return err;
884
885 rtnl_link_failed:
886         xfrm4_mode_tunnel_input_deregister(&vti_handler);
887         unregister_pernet_device(&vti_net_ops);
888         return err;
889 }
890
891 static void __exit vti_fini(void)
892 {
893         rtnl_link_unregister(&vti_link_ops);
894         if (xfrm4_mode_tunnel_input_deregister(&vti_handler))
895                 pr_info("vti close: can't deregister tunnel\n");
896
897         unregister_pernet_device(&vti_net_ops);
898 }
899
900 module_init(vti_init);
901 module_exit(vti_fini);
902 MODULE_LICENSE("GPL");
903 MODULE_ALIAS_RTNL_LINK("vti");
904 MODULE_ALIAS_NETDEV("ip_vti0");