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net: fix feature changes on devices without ndo_set_features
[linux-stable.git] / net / ipv6 / sit.c
blobdcccae86190f2a29c5ea8199320bbf399c7350b1
1 /*
2 * IPv6 over IPv4 tunnel device - Simple Internet Transition (SIT)
3 * Linux INET6 implementation
4 *
5 * Authors:
6 * Pedro Roque <roque@di.fc.ul.pt>
7 * Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
8 *
9 * This program is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU General Public License
11 * as published by the Free Software Foundation; either version
12 * 2 of the License, or (at your option) any later version.
13 *
14 * Changes:
15 * Roger Venning <r.venning@telstra.com>: 6to4 support
16 * Nate Thompson <nate@thebog.net>: 6to4 support
17 * Fred Templin <fred.l.templin@boeing.com>: isatap support
18 */
19
20 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
21
22 #include <linux/module.h>
23 #include <linux/capability.h>
24 #include <linux/errno.h>
25 #include <linux/types.h>
26 #include <linux/socket.h>
27 #include <linux/sockios.h>
28 #include <linux/net.h>
29 #include <linux/in6.h>
30 #include <linux/netdevice.h>
31 #include <linux/if_arp.h>
32 #include <linux/icmp.h>
33 #include <linux/slab.h>
34 #include <asm/uaccess.h>
35 #include <linux/init.h>
36 #include <linux/netfilter_ipv4.h>
37 #include <linux/if_ether.h>
38
39 #include <net/sock.h>
40 #include <net/snmp.h>
41
42 #include <net/ipv6.h>
43 #include <net/protocol.h>
44 #include <net/transp_v6.h>
45 #include <net/ip6_fib.h>
46 #include <net/ip6_route.h>
47 #include <net/ndisc.h>
48 #include <net/addrconf.h>
49 #include <net/ip.h>
50 #include <net/udp.h>
51 #include <net/icmp.h>
52 #include <net/ip_tunnels.h>
53 #include <net/inet_ecn.h>
54 #include <net/xfrm.h>
55 #include <net/dsfield.h>
56 #include <net/net_namespace.h>
57 #include <net/netns/generic.h>
58
59 /*
60 This version of net/ipv6/sit.c is cloned of net/ipv4/ip_gre.c
61
62 For comments look at net/ipv4/ip_gre.c --ANK
63 */
64
65 #define HASH_SIZE 16
66 #define HASH(addr) (((__force u32)addr^((__force u32)addr>>4))&0xF)
67
68 static bool log_ecn_error = true;
69 module_param(log_ecn_error, bool, 0644);
70 MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN");
71
72 static int ipip6_tunnel_init(struct net_device *dev);
73 static void ipip6_tunnel_setup(struct net_device *dev);
74 static void ipip6_dev_free(struct net_device *dev);
75 static bool check_6rd(struct ip_tunnel *tunnel, const struct in6_addr *v6dst,
76 __be32 *v4dst);
77 static struct rtnl_link_ops sit_link_ops __read_mostly;
78
79 static int sit_net_id __read_mostly;
80 struct sit_net {
81 struct ip_tunnel __rcu *tunnels_r_l[HASH_SIZE];
82 struct ip_tunnel __rcu *tunnels_r[HASH_SIZE];
83 struct ip_tunnel __rcu *tunnels_l[HASH_SIZE];
84 struct ip_tunnel __rcu *tunnels_wc[1];
85 struct ip_tunnel __rcu **tunnels[4];
86
87 struct net_device *fb_tunnel_dev;
88 };
89
90 /*
91 * Must be invoked with rcu_read_lock
92 */
93 static struct ip_tunnel *ipip6_tunnel_lookup(struct net *net,
94 struct net_device *dev, __be32 remote, __be32 local)
95 {
96 unsigned int h0 = HASH(remote);
97 unsigned int h1 = HASH(local);
98 struct ip_tunnel *t;
99 struct sit_net *sitn = net_generic(net, sit_net_id);
100
101 for_each_ip_tunnel_rcu(t, sitn->tunnels_r_l[h0 ^ h1]) {
102 if (local == t->parms.iph.saddr &&
103 remote == t->parms.iph.daddr &&
104 (!dev || !t->parms.link || dev->ifindex == t->parms.link) &&
105 (t->dev->flags & IFF_UP))
106 return t;
107 }
108 for_each_ip_tunnel_rcu(t, sitn->tunnels_r[h0]) {
109 if (remote == t->parms.iph.daddr &&
110 (!dev || !t->parms.link || dev->ifindex == t->parms.link) &&
111 (t->dev->flags & IFF_UP))
112 return t;
113 }
114 for_each_ip_tunnel_rcu(t, sitn->tunnels_l[h1]) {
115 if (local == t->parms.iph.saddr &&
116 (!dev || !t->parms.link || dev->ifindex == t->parms.link) &&
117 (t->dev->flags & IFF_UP))
118 return t;
119 }
120 t = rcu_dereference(sitn->tunnels_wc[0]);
121 if (t && (t->dev->flags & IFF_UP))
122 return t;
123 return NULL;
124 }
125
126 static struct ip_tunnel __rcu **__ipip6_bucket(struct sit_net *sitn,
127 struct ip_tunnel_parm *parms)
128 {
129 __be32 remote = parms->iph.daddr;
130 __be32 local = parms->iph.saddr;
131 unsigned int h = 0;
132 int prio = 0;
133
134 if (remote) {
135 prio |= 2;
136 h ^= HASH(remote);
137 }
138 if (local) {
139 prio |= 1;
140 h ^= HASH(local);
141 }
142 return &sitn->tunnels[prio][h];
143 }
144
145 static inline struct ip_tunnel __rcu **ipip6_bucket(struct sit_net *sitn,
146 struct ip_tunnel *t)
147 {
148 return __ipip6_bucket(sitn, &t->parms);
149 }
150
151 static void ipip6_tunnel_unlink(struct sit_net *sitn, struct ip_tunnel *t)
152 {
153 struct ip_tunnel __rcu **tp;
154 struct ip_tunnel *iter;
155
156 for (tp = ipip6_bucket(sitn, t);
157 (iter = rtnl_dereference(*tp)) != NULL;
158 tp = &iter->next) {
159 if (t == iter) {
160 rcu_assign_pointer(*tp, t->next);
161 break;
162 }
163 }
164 }
165
166 static void ipip6_tunnel_link(struct sit_net *sitn, struct ip_tunnel *t)
167 {
168 struct ip_tunnel __rcu **tp = ipip6_bucket(sitn, t);
169
170 rcu_assign_pointer(t->next, rtnl_dereference(*tp));
171 rcu_assign_pointer(*tp, t);
172 }
173
174 static void ipip6_tunnel_clone_6rd(struct net_device *dev, struct sit_net *sitn)
175 {
176 #ifdef CONFIG_IPV6_SIT_6RD
177 struct ip_tunnel *t = netdev_priv(dev);
178
179 if (t->dev == sitn->fb_tunnel_dev) {
180 ipv6_addr_set(&t->ip6rd.prefix, htonl(0x20020000), 0, 0, 0);
181 t->ip6rd.relay_prefix = 0;
182 t->ip6rd.prefixlen = 16;
183 t->ip6rd.relay_prefixlen = 0;
184 } else {
185 struct ip_tunnel *t0 = netdev_priv(sitn->fb_tunnel_dev);
186 memcpy(&t->ip6rd, &t0->ip6rd, sizeof(t->ip6rd));
187 }
188 #endif
189 }
190
191 static int ipip6_tunnel_create(struct net_device *dev)
192 {
193 struct ip_tunnel *t = netdev_priv(dev);
194 struct net *net = dev_net(dev);
195 struct sit_net *sitn = net_generic(net, sit_net_id);
196 int err;
197
198 memcpy(dev->dev_addr, &t->parms.iph.saddr, 4);
199 memcpy(dev->broadcast, &t->parms.iph.daddr, 4);
200
201 if ((__force u16)t->parms.i_flags & SIT_ISATAP)
202 dev->priv_flags |= IFF_ISATAP;
203
204 err = register_netdevice(dev);
205 if (err < 0)
206 goto out;
207
208 ipip6_tunnel_clone_6rd(dev, sitn);
209
210 dev->rtnl_link_ops = &sit_link_ops;
211
212 dev_hold(dev);
213
214 ipip6_tunnel_link(sitn, t);
215 return 0;
216
217 out:
218 return err;
219 }
220
221 static struct ip_tunnel *ipip6_tunnel_locate(struct net *net,
222 struct ip_tunnel_parm *parms, int create)
223 {
224 __be32 remote = parms->iph.daddr;
225 __be32 local = parms->iph.saddr;
226 struct ip_tunnel *t, *nt;
227 struct ip_tunnel __rcu **tp;
228 struct net_device *dev;
229 char name[IFNAMSIZ];
230 struct sit_net *sitn = net_generic(net, sit_net_id);
231
232 for (tp = __ipip6_bucket(sitn, parms);
233 (t = rtnl_dereference(*tp)) != NULL;
234 tp = &t->next) {
235 if (local == t->parms.iph.saddr &&
236 remote == t->parms.iph.daddr &&
237 parms->link == t->parms.link) {
238 if (create)
239 return NULL;
240 else
241 return t;
242 }
243 }
244 if (!create)
245 goto failed;
246
247 if (parms->name[0])
248 strlcpy(name, parms->name, IFNAMSIZ);
249 else
250 strcpy(name, "sit%d");
251
252 dev = alloc_netdev(sizeof(*t), name, NET_NAME_UNKNOWN,
253 ipip6_tunnel_setup);
254 if (!dev)
255 return NULL;
256
257 dev_net_set(dev, net);
258
259 nt = netdev_priv(dev);
260
261 nt->parms = *parms;
262 if (ipip6_tunnel_create(dev) < 0)
263 goto failed_free;
264
265 return nt;
266
267 failed_free:
268 ipip6_dev_free(dev);
269 failed:
270 return NULL;
271 }
272
273 #define for_each_prl_rcu(start) \
274 for (prl = rcu_dereference(start); \
275 prl; \
276 prl = rcu_dereference(prl->next))
277
278 static struct ip_tunnel_prl_entry *
279 __ipip6_tunnel_locate_prl(struct ip_tunnel *t, __be32 addr)
280 {
281 struct ip_tunnel_prl_entry *prl;
282
283 for_each_prl_rcu(t->prl)
284 if (prl->addr == addr)
285 break;
286 return prl;
287
288 }
289
290 static int ipip6_tunnel_get_prl(struct ip_tunnel *t,
291 struct ip_tunnel_prl __user *a)
292 {
293 struct ip_tunnel_prl kprl, *kp;
294 struct ip_tunnel_prl_entry *prl;
295 unsigned int cmax, c = 0, ca, len;
296 int ret = 0;
297
298 if (copy_from_user(&kprl, a, sizeof(kprl)))
299 return -EFAULT;
300 cmax = kprl.datalen / sizeof(kprl);
301 if (cmax > 1 && kprl.addr != htonl(INADDR_ANY))
302 cmax = 1;
303
304 /* For simple GET or for root users,
305 * we try harder to allocate.
306 */
307 kp = (cmax <= 1 || capable(CAP_NET_ADMIN)) ?
308 kcalloc(cmax, sizeof(*kp), GFP_KERNEL) :
309 NULL;
310
311 rcu_read_lock();
312
313 ca = t->prl_count < cmax ? t->prl_count : cmax;
314
315 if (!kp) {
316 /* We don't try hard to allocate much memory for
317 * non-root users.
318 * For root users, retry allocating enough memory for
319 * the answer.
320 */
321 kp = kcalloc(ca, sizeof(*kp), GFP_ATOMIC);
322 if (!kp) {
323 ret = -ENOMEM;
324 goto out;
325 }
326 }
327
328 c = 0;
329 for_each_prl_rcu(t->prl) {
330 if (c >= cmax)
331 break;
332 if (kprl.addr != htonl(INADDR_ANY) && prl->addr != kprl.addr)
333 continue;
334 kp[c].addr = prl->addr;
335 kp[c].flags = prl->flags;
336 c++;
337 if (kprl.addr != htonl(INADDR_ANY))
338 break;
339 }
340 out:
341 rcu_read_unlock();
342
343 len = sizeof(*kp) * c;
344 ret = 0;
345 if ((len && copy_to_user(a + 1, kp, len)) || put_user(len, &a->datalen))
346 ret = -EFAULT;
347
348 kfree(kp);
349
350 return ret;
351 }
352
353 static int
354 ipip6_tunnel_add_prl(struct ip_tunnel *t, struct ip_tunnel_prl *a, int chg)
355 {
356 struct ip_tunnel_prl_entry *p;
357 int err = 0;
358
359 if (a->addr == htonl(INADDR_ANY))
360 return -EINVAL;
361
362 ASSERT_RTNL();
363
364 for (p = rtnl_dereference(t->prl); p; p = rtnl_dereference(p->next)) {
365 if (p->addr == a->addr) {
366 if (chg) {
367 p->flags = a->flags;
368 goto out;
369 }
370 err = -EEXIST;
371 goto out;
372 }
373 }
374
375 if (chg) {
376 err = -ENXIO;
377 goto out;
378 }
379
380 p = kzalloc(sizeof(struct ip_tunnel_prl_entry), GFP_KERNEL);
381 if (!p) {
382 err = -ENOBUFS;
383 goto out;
384 }
385
386 p->next = t->prl;
387 p->addr = a->addr;
388 p->flags = a->flags;
389 t->prl_count++;
390 rcu_assign_pointer(t->prl, p);
391 out:
392 return err;
393 }
394
395 static void prl_list_destroy_rcu(struct rcu_head *head)
396 {
397 struct ip_tunnel_prl_entry *p, *n;
398
399 p = container_of(head, struct ip_tunnel_prl_entry, rcu_head);
400 do {
401 n = rcu_dereference_protected(p->next, 1);
402 kfree(p);
403 p = n;
404 } while (p);
405 }
406
407 static int
408 ipip6_tunnel_del_prl(struct ip_tunnel *t, struct ip_tunnel_prl *a)
409 {
410 struct ip_tunnel_prl_entry *x;
411 struct ip_tunnel_prl_entry __rcu **p;
412 int err = 0;
413
414 ASSERT_RTNL();
415
416 if (a && a->addr != htonl(INADDR_ANY)) {
417 for (p = &t->prl;
418 (x = rtnl_dereference(*p)) != NULL;
419 p = &x->next) {
420 if (x->addr == a->addr) {
421 *p = x->next;
422 kfree_rcu(x, rcu_head);
423 t->prl_count--;
424 goto out;
425 }
426 }
427 err = -ENXIO;
428 } else {
429 x = rtnl_dereference(t->prl);
430 if (x) {
431 t->prl_count = 0;
432 call_rcu(&x->rcu_head, prl_list_destroy_rcu);
433 t->prl = NULL;
434 }
435 }
436 out:
437 return err;
438 }
439
440 static int
441 isatap_chksrc(struct sk_buff *skb, const struct iphdr *iph, struct ip_tunnel *t)
442 {
443 struct ip_tunnel_prl_entry *p;
444 int ok = 1;
445
446 rcu_read_lock();
447 p = __ipip6_tunnel_locate_prl(t, iph->saddr);
448 if (p) {
449 if (p->flags & PRL_DEFAULT)
450 skb->ndisc_nodetype = NDISC_NODETYPE_DEFAULT;
451 else
452 skb->ndisc_nodetype = NDISC_NODETYPE_NODEFAULT;
453 } else {
454 const struct in6_addr *addr6 = &ipv6_hdr(skb)->saddr;
455
456 if (ipv6_addr_is_isatap(addr6) &&
457 (addr6->s6_addr32[3] == iph->saddr) &&
458 ipv6_chk_prefix(addr6, t->dev))
459 skb->ndisc_nodetype = NDISC_NODETYPE_HOST;
460 else
461 ok = 0;
462 }
463 rcu_read_unlock();
464 return ok;
465 }
466
467 static void ipip6_tunnel_uninit(struct net_device *dev)
468 {
469 struct ip_tunnel *tunnel = netdev_priv(dev);
470 struct sit_net *sitn = net_generic(tunnel->net, sit_net_id);
471
472 if (dev == sitn->fb_tunnel_dev) {
473 RCU_INIT_POINTER(sitn->tunnels_wc[0], NULL);
474 } else {
475 ipip6_tunnel_unlink(sitn, tunnel);
476 ipip6_tunnel_del_prl(tunnel, NULL);
477 }
478 ip_tunnel_dst_reset_all(tunnel);
479 dev_put(dev);
480 }
481
482 /* Generate icmpv6 with type/code ICMPV6_DEST_UNREACH/ICMPV6_ADDR_UNREACH
483 * if sufficient data bytes are available
484 */
485 static int ipip6_err_gen_icmpv6_unreach(struct sk_buff *skb)
486 {
487 int ihl = ((const struct iphdr *)skb->data)->ihl*4;
488 struct rt6_info *rt;
489 struct sk_buff *skb2;
490
491 if (!pskb_may_pull(skb, ihl + sizeof(struct ipv6hdr) + 8))
492 return 1;
493
494 skb2 = skb_clone(skb, GFP_ATOMIC);
495
496 if (!skb2)
497 return 1;
498
499 skb_dst_drop(skb2);
500 skb_pull(skb2, ihl);
501 skb_reset_network_header(skb2);
502
503 rt = rt6_lookup(dev_net(skb->dev), &ipv6_hdr(skb2)->saddr, NULL, 0, 0);
504
505 if (rt && rt->dst.dev)
506 skb2->dev = rt->dst.dev;
507
508 icmpv6_send(skb2, ICMPV6_DEST_UNREACH, ICMPV6_ADDR_UNREACH, 0);
509
510 if (rt)
511 ip6_rt_put(rt);
512
513 kfree_skb(skb2);
514
515 return 0;
516 }
517
518 static int ipip6_err(struct sk_buff *skb, u32 info)
519 {
520 const struct iphdr *iph = (const struct iphdr *)skb->data;
521 const int type = icmp_hdr(skb)->type;
522 const int code = icmp_hdr(skb)->code;
523 struct ip_tunnel *t;
524 int err;
525
526 switch (type) {
527 default:
528 case ICMP_PARAMETERPROB:
529 return 0;
530
531 case ICMP_DEST_UNREACH:
532 switch (code) {
533 case ICMP_SR_FAILED:
534 /* Impossible event. */
535 return 0;
536 default:
537 /* All others are translated to HOST_UNREACH.
538 rfc2003 contains "deep thoughts" about NET_UNREACH,
539 I believe they are just ether pollution. --ANK
540 */
541 break;
542 }
543 break;
544 case ICMP_TIME_EXCEEDED:
545 if (code != ICMP_EXC_TTL)
546 return 0;
547 break;
548 case ICMP_REDIRECT:
549 break;
550 }
551
552 err = -ENOENT;
553
554 t = ipip6_tunnel_lookup(dev_net(skb->dev),
555 skb->dev,
556 iph->daddr,
557 iph->saddr);
558 if (!t)
559 goto out;
560
561 if (type == ICMP_DEST_UNREACH && code == ICMP_FRAG_NEEDED) {
562 ipv4_update_pmtu(skb, dev_net(skb->dev), info,
563 t->parms.link, 0, IPPROTO_IPV6, 0);
564 err = 0;
565 goto out;
566 }
567 if (type == ICMP_REDIRECT) {
568 ipv4_redirect(skb, dev_net(skb->dev), t->parms.link, 0,
569 IPPROTO_IPV6, 0);
570 err = 0;
571 goto out;
572 }
573
574 if (t->parms.iph.daddr == 0)
575 goto out;
576
577 err = 0;
578 if (!ipip6_err_gen_icmpv6_unreach(skb))
579 goto out;
580
581 if (t->parms.iph.ttl == 0 && type == ICMP_TIME_EXCEEDED)
582 goto out;
583
584 if (time_before(jiffies, t->err_time + IPTUNNEL_ERR_TIMEO))
585 t->err_count++;
586 else
587 t->err_count = 1;
588 t->err_time = jiffies;
589 out:
590 return err;
591 }
592
593 static inline bool is_spoofed_6rd(struct ip_tunnel *tunnel, const __be32 v4addr,
594 const struct in6_addr *v6addr)
595 {
596 __be32 v4embed = 0;
597 if (check_6rd(tunnel, v6addr, &v4embed) && v4addr != v4embed)
598 return true;
599 return false;
600 }
601
602 /* Checks if an address matches an address on the tunnel interface.
603 * Used to detect the NAT of proto 41 packets and let them pass spoofing test.
604 * Long story:
605 * This function is called after we considered the packet as spoofed
606 * in is_spoofed_6rd.
607 * We may have a router that is doing NAT for proto 41 packets
608 * for an internal station. Destination a.a.a.a/PREFIX:bbbb:bbbb
609 * will be translated to n.n.n.n/PREFIX:bbbb:bbbb. And is_spoofed_6rd
610 * function will return true, dropping the packet.
611 * But, we can still check if is spoofed against the IP
612 * addresses associated with the interface.
613 */
614 static bool only_dnatted(const struct ip_tunnel *tunnel,
615 const struct in6_addr *v6dst)
616 {
617 int prefix_len;
618
619 #ifdef CONFIG_IPV6_SIT_6RD
620 prefix_len = tunnel->ip6rd.prefixlen + 32
621 - tunnel->ip6rd.relay_prefixlen;
622 #else
623 prefix_len = 48;
624 #endif
625 return ipv6_chk_custom_prefix(v6dst, prefix_len, tunnel->dev);
626 }
627
628 /* Returns true if a packet is spoofed */
629 static bool packet_is_spoofed(struct sk_buff *skb,
630 const struct iphdr *iph,
631 struct ip_tunnel *tunnel)
632 {
633 const struct ipv6hdr *ipv6h;
634
635 if (tunnel->dev->priv_flags & IFF_ISATAP) {
636 if (!isatap_chksrc(skb, iph, tunnel))
637 return true;
638
639 return false;
640 }
641
642 if (tunnel->dev->flags & IFF_POINTOPOINT)
643 return false;
644
645 ipv6h = ipv6_hdr(skb);
646
647 if (unlikely(is_spoofed_6rd(tunnel, iph->saddr, &ipv6h->saddr))) {
648 net_warn_ratelimited("Src spoofed %pI4/%pI6c -> %pI4/%pI6c\n",
649 &iph->saddr, &ipv6h->saddr,
650 &iph->daddr, &ipv6h->daddr);
651 return true;
652 }
653
654 if (likely(!is_spoofed_6rd(tunnel, iph->daddr, &ipv6h->daddr)))
655 return false;
656
657 if (only_dnatted(tunnel, &ipv6h->daddr))
658 return false;
659
660 net_warn_ratelimited("Dst spoofed %pI4/%pI6c -> %pI4/%pI6c\n",
661 &iph->saddr, &ipv6h->saddr,
662 &iph->daddr, &ipv6h->daddr);
663 return true;
664 }
665
666 static int ipip6_rcv(struct sk_buff *skb)
667 {
668 const struct iphdr *iph = ip_hdr(skb);
669 struct ip_tunnel *tunnel;
670 int err;
671
672 tunnel = ipip6_tunnel_lookup(dev_net(skb->dev), skb->dev,
673 iph->saddr, iph->daddr);
674 if (tunnel) {
675 struct pcpu_sw_netstats *tstats;
676
677 if (tunnel->parms.iph.protocol != IPPROTO_IPV6 &&
678 tunnel->parms.iph.protocol != 0)
679 goto out;
680
681 skb->mac_header = skb->network_header;
682 skb_reset_network_header(skb);
683 IPCB(skb)->flags = 0;
684 skb->protocol = htons(ETH_P_IPV6);
685
686 if (packet_is_spoofed(skb, iph, tunnel)) {
687 tunnel->dev->stats.rx_errors++;
688 goto out;
689 }
690
691 __skb_tunnel_rx(skb, tunnel->dev, tunnel->net);
692
693 err = IP_ECN_decapsulate(iph, skb);
694 if (unlikely(err)) {
695 if (log_ecn_error)
696 net_info_ratelimited("non-ECT from %pI4 with TOS=%#x\n",
697 &iph->saddr, iph->tos);
698 if (err > 1) {
699 ++tunnel->dev->stats.rx_frame_errors;
700 ++tunnel->dev->stats.rx_errors;
701 goto out;
702 }
703 }
704
705 tstats = this_cpu_ptr(tunnel->dev->tstats);
706 u64_stats_update_begin(&tstats->syncp);
707 tstats->rx_packets++;
708 tstats->rx_bytes += skb->len;
709 u64_stats_update_end(&tstats->syncp);
710
711 netif_rx(skb);
712
713 return 0;
714 }
715
716 /* no tunnel matched, let upstream know, ipsec may handle it */
717 return 1;
718 out:
719 kfree_skb(skb);
720 return 0;
721 }
722
723 static const struct tnl_ptk_info tpi = {
724 /* no tunnel info required for ipip. */
725 .proto = htons(ETH_P_IP),
726 };
727
728 static int ipip_rcv(struct sk_buff *skb)
729 {
730 const struct iphdr *iph;
731 struct ip_tunnel *tunnel;
732
733 iph = ip_hdr(skb);
734 tunnel = ipip6_tunnel_lookup(dev_net(skb->dev), skb->dev,
735 iph->saddr, iph->daddr);
736 if (tunnel) {
737 if (tunnel->parms.iph.protocol != IPPROTO_IPIP &&
738 tunnel->parms.iph.protocol != 0)
739 goto drop;
740
741 if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb))
742 goto drop;
743 if (iptunnel_pull_header(skb, 0, tpi.proto))
744 goto drop;
745 return ip_tunnel_rcv(tunnel, skb, &tpi, NULL, log_ecn_error);
746 }
747
748 return 1;
749
750 drop:
751 kfree_skb(skb);
752 return 0;
753 }
754
755 /*
756 * If the IPv6 address comes from 6rd / 6to4 (RFC 3056) addr space this function
757 * stores the embedded IPv4 address in v4dst and returns true.
758 */
759 static bool check_6rd(struct ip_tunnel *tunnel, const struct in6_addr *v6dst,
760 __be32 *v4dst)
761 {
762 #ifdef CONFIG_IPV6_SIT_6RD
763 if (ipv6_prefix_equal(v6dst, &tunnel->ip6rd.prefix,
764 tunnel->ip6rd.prefixlen)) {
765 unsigned int pbw0, pbi0;
766 int pbi1;
767 u32 d;
768
769 pbw0 = tunnel->ip6rd.prefixlen >> 5;
770 pbi0 = tunnel->ip6rd.prefixlen & 0x1f;
771
772 d = (ntohl(v6dst->s6_addr32[pbw0]) << pbi0) >>
773 tunnel->ip6rd.relay_prefixlen;
774
775 pbi1 = pbi0 - tunnel->ip6rd.relay_prefixlen;
776 if (pbi1 > 0)
777 d |= ntohl(v6dst->s6_addr32[pbw0 + 1]) >>
778 (32 - pbi1);
779
780 *v4dst = tunnel->ip6rd.relay_prefix | htonl(d);
781 return true;
782 }
783 #else
784 if (v6dst->s6_addr16[0] == htons(0x2002)) {
785 /* 6to4 v6 addr has 16 bits prefix, 32 v4addr, 16 SLA, ... */
786 memcpy(v4dst, &v6dst->s6_addr16[1], 4);
787 return true;
788 }
789 #endif
790 return false;
791 }
792
793 static inline __be32 try_6rd(struct ip_tunnel *tunnel,
794 const struct in6_addr *v6dst)
795 {
796 __be32 dst = 0;
797 check_6rd(tunnel, v6dst, &dst);
798 return dst;
799 }
800
801 /*
802 * This function assumes it is being called from dev_queue_xmit()
803 * and that skb is filled properly by that function.
804 */
805
806 static netdev_tx_t ipip6_tunnel_xmit(struct sk_buff *skb,
807 struct net_device *dev)
808 {
809 struct ip_tunnel *tunnel = netdev_priv(dev);
810 const struct iphdr *tiph = &tunnel->parms.iph;
811 const struct ipv6hdr *iph6 = ipv6_hdr(skb);
812 u8 tos = tunnel->parms.iph.tos;
813 __be16 df = tiph->frag_off;
814 struct rtable *rt; /* Route to the other host */
815 struct net_device *tdev; /* Device to other host */
816 unsigned int max_headroom; /* The extra header space needed */
817 __be32 dst = tiph->daddr;
818 struct flowi4 fl4;
819 int mtu;
820 const struct in6_addr *addr6;
821 int addr_type;
822 u8 ttl;
823 int err;
824 u8 protocol = IPPROTO_IPV6;
825 int t_hlen = tunnel->hlen + sizeof(struct iphdr);
826
827 if (skb->protocol != htons(ETH_P_IPV6))
828 goto tx_error;
829
830 if (tos == 1)
831 tos = ipv6_get_dsfield(iph6);
832
833 /* ISATAP (RFC4214) - must come before 6to4 */
834 if (dev->priv_flags & IFF_ISATAP) {
835 struct neighbour *neigh = NULL;
836 bool do_tx_error = false;
837
838 if (skb_dst(skb))
839 neigh = dst_neigh_lookup(skb_dst(skb), &iph6->daddr);
840
841 if (!neigh) {
842 net_dbg_ratelimited("nexthop == NULL\n");
843 goto tx_error;
844 }
845
846 addr6 = (const struct in6_addr *)&neigh->primary_key;
847 addr_type = ipv6_addr_type(addr6);
848
849 if ((addr_type & IPV6_ADDR_UNICAST) &&
850 ipv6_addr_is_isatap(addr6))
851 dst = addr6->s6_addr32[3];
852 else
853 do_tx_error = true;
854
855 neigh_release(neigh);
856 if (do_tx_error)
857 goto tx_error;
858 }
859
860 if (!dst)
861 dst = try_6rd(tunnel, &iph6->daddr);
862
863 if (!dst) {
864 struct neighbour *neigh = NULL;
865 bool do_tx_error = false;
866
867 if (skb_dst(skb))
868 neigh = dst_neigh_lookup(skb_dst(skb), &iph6->daddr);
869
870 if (!neigh) {
871 net_dbg_ratelimited("nexthop == NULL\n");
872 goto tx_error;
873 }
874
875 addr6 = (const struct in6_addr *)&neigh->primary_key;
876 addr_type = ipv6_addr_type(addr6);
877
878 if (addr_type == IPV6_ADDR_ANY) {
879 addr6 = &ipv6_hdr(skb)->daddr;
880 addr_type = ipv6_addr_type(addr6);
881 }
882
883 if ((addr_type & IPV6_ADDR_COMPATv4) != 0)
884 dst = addr6->s6_addr32[3];
885 else
886 do_tx_error = true;
887
888 neigh_release(neigh);
889 if (do_tx_error)
890 goto tx_error;
891 }
892
893 rt = ip_route_output_ports(tunnel->net, &fl4, NULL,
894 dst, tiph->saddr,
895 0, 0,
896 IPPROTO_IPV6, RT_TOS(tos),
897 tunnel->parms.link);
898 if (IS_ERR(rt)) {
899 dev->stats.tx_carrier_errors++;
900 goto tx_error_icmp;
901 }
902 if (rt->rt_type != RTN_UNICAST) {
903 ip_rt_put(rt);
904 dev->stats.tx_carrier_errors++;
905 goto tx_error_icmp;
906 }
907 tdev = rt->dst.dev;
908
909 if (tdev == dev) {
910 ip_rt_put(rt);
911 dev->stats.collisions++;
912 goto tx_error;
913 }
914
915 skb = iptunnel_handle_offloads(skb, false, SKB_GSO_SIT);
916 if (IS_ERR(skb)) {
917 ip_rt_put(rt);
918 goto out;
919 }
920
921 if (df) {
922 mtu = dst_mtu(&rt->dst) - t_hlen;
923
924 if (mtu < 68) {
925 dev->stats.collisions++;
926 ip_rt_put(rt);
927 goto tx_error;
928 }
929
930 if (mtu < IPV6_MIN_MTU) {
931 mtu = IPV6_MIN_MTU;
932 df = 0;
933 }
934
935 if (tunnel->parms.iph.daddr && skb_dst(skb))
936 skb_dst(skb)->ops->update_pmtu(skb_dst(skb), NULL, skb, mtu);
937
938 if (skb->len > mtu && !skb_is_gso(skb)) {
939 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
940 ip_rt_put(rt);
941 goto tx_error;
942 }
943 }
944
945 if (tunnel->err_count > 0) {
946 if (time_before(jiffies,
947 tunnel->err_time + IPTUNNEL_ERR_TIMEO)) {
948 tunnel->err_count--;
949 dst_link_failure(skb);
950 } else
951 tunnel->err_count = 0;
952 }
953
954 /*
955 * Okay, now see if we can stuff it in the buffer as-is.
956 */
957 max_headroom = LL_RESERVED_SPACE(tdev) + t_hlen;
958
959 if (skb_headroom(skb) < max_headroom || skb_shared(skb) ||
960 (skb_cloned(skb) && !skb_clone_writable(skb, 0))) {
961 struct sk_buff *new_skb = skb_realloc_headroom(skb, max_headroom);
962 if (!new_skb) {
963 ip_rt_put(rt);
964 dev->stats.tx_dropped++;
965 kfree_skb(skb);
966 return NETDEV_TX_OK;
967 }
968 if (skb->sk)
969 skb_set_owner_w(new_skb, skb->sk);
970 dev_kfree_skb(skb);
971 skb = new_skb;
972 iph6 = ipv6_hdr(skb);
973 }
974 ttl = tiph->ttl;
975 if (ttl == 0)
976 ttl = iph6->hop_limit;
977 tos = INET_ECN_encapsulate(tos, ipv6_get_dsfield(iph6));
978
979 if (ip_tunnel_encap(skb, tunnel, &protocol, &fl4) < 0) {
980 ip_rt_put(rt);
981 goto tx_error;
982 }
983
984 skb_set_inner_ipproto(skb, IPPROTO_IPV6);
985
986 err = iptunnel_xmit(NULL, rt, skb, fl4.saddr, fl4.daddr,
987 protocol, tos, ttl, df,
988 !net_eq(tunnel->net, dev_net(dev)));
989 iptunnel_xmit_stats(err, &dev->stats, dev->tstats);
990 return NETDEV_TX_OK;
991
992 tx_error_icmp:
993 dst_link_failure(skb);
994 tx_error:
995 kfree_skb(skb);
996 out:
997 dev->stats.tx_errors++;
998 return NETDEV_TX_OK;
999 }
1000
1001 static netdev_tx_t ipip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev)
1002 {
1003 struct ip_tunnel *tunnel = netdev_priv(dev);
1004 const struct iphdr *tiph = &tunnel->parms.iph;
1005
1006 skb = iptunnel_handle_offloads(skb, false, SKB_GSO_IPIP);
1007 if (IS_ERR(skb))
1008 goto out;
1009
1010 skb_set_inner_ipproto(skb, IPPROTO_IPIP);
1011
1012 ip_tunnel_xmit(skb, dev, tiph, IPPROTO_IPIP);
1013 return NETDEV_TX_OK;
1014 out:
1015 dev->stats.tx_errors++;
1016 return NETDEV_TX_OK;
1017 }
1018
1019 static netdev_tx_t sit_tunnel_xmit(struct sk_buff *skb,
1020 struct net_device *dev)
1021 {
1022 switch (skb->protocol) {
1023 case htons(ETH_P_IP):
1024 ipip_tunnel_xmit(skb, dev);
1025 break;
1026 case htons(ETH_P_IPV6):
1027 ipip6_tunnel_xmit(skb, dev);
1028 break;
1029 default:
1030 goto tx_err;
1031 }
1032
1033 return NETDEV_TX_OK;
1034
1035 tx_err:
1036 dev->stats.tx_errors++;
1037 kfree_skb(skb);
1038 return NETDEV_TX_OK;
1039
1040 }
1041
1042 static void ipip6_tunnel_bind_dev(struct net_device *dev)
1043 {
1044 struct net_device *tdev = NULL;
1045 struct ip_tunnel *tunnel;
1046 const struct iphdr *iph;
1047 struct flowi4 fl4;
1048
1049 tunnel = netdev_priv(dev);
1050 iph = &tunnel->parms.iph;
1051
1052 if (iph->daddr) {
1053 struct rtable *rt = ip_route_output_ports(tunnel->net, &fl4,
1054 NULL,
1055 iph->daddr, iph->saddr,
1056 0, 0,
1057 IPPROTO_IPV6,
1058 RT_TOS(iph->tos),
1059 tunnel->parms.link);
1060
1061 if (!IS_ERR(rt)) {
1062 tdev = rt->dst.dev;
1063 ip_rt_put(rt);
1064 }
1065 dev->flags |= IFF_POINTOPOINT;
1066 }
1067
1068 if (!tdev && tunnel->parms.link)
1069 tdev = __dev_get_by_index(tunnel->net, tunnel->parms.link);
1070
1071 if (tdev) {
1072 int t_hlen = tunnel->hlen + sizeof(struct iphdr);
1073
1074 dev->hard_header_len = tdev->hard_header_len + sizeof(struct iphdr);
1075 dev->mtu = tdev->mtu - t_hlen;
1076 if (dev->mtu < IPV6_MIN_MTU)
1077 dev->mtu = IPV6_MIN_MTU;
1078 }
1079 }
1080
1081 static void ipip6_tunnel_update(struct ip_tunnel *t, struct ip_tunnel_parm *p)
1082 {
1083 struct net *net = t->net;
1084 struct sit_net *sitn = net_generic(net, sit_net_id);
1085
1086 ipip6_tunnel_unlink(sitn, t);
1087 synchronize_net();
1088 t->parms.iph.saddr = p->iph.saddr;
1089 t->parms.iph.daddr = p->iph.daddr;
1090 memcpy(t->dev->dev_addr, &p->iph.saddr, 4);
1091 memcpy(t->dev->broadcast, &p->iph.daddr, 4);
1092 ipip6_tunnel_link(sitn, t);
1093 t->parms.iph.ttl = p->iph.ttl;
1094 t->parms.iph.tos = p->iph.tos;
1095 if (t->parms.link != p->link) {
1096 t->parms.link = p->link;
1097 ipip6_tunnel_bind_dev(t->dev);
1098 }
1099 ip_tunnel_dst_reset_all(t);
1100 netdev_state_change(t->dev);
1101 }
1102
1103 #ifdef CONFIG_IPV6_SIT_6RD
1104 static int ipip6_tunnel_update_6rd(struct ip_tunnel *t,
1105 struct ip_tunnel_6rd *ip6rd)
1106 {
1107 struct in6_addr prefix;
1108 __be32 relay_prefix;
1109
1110 if (ip6rd->relay_prefixlen > 32 ||
1111 ip6rd->prefixlen + (32 - ip6rd->relay_prefixlen) > 64)
1112 return -EINVAL;
1113
1114 ipv6_addr_prefix(&prefix, &ip6rd->prefix, ip6rd->prefixlen);
1115 if (!ipv6_addr_equal(&prefix, &ip6rd->prefix))
1116 return -EINVAL;
1117 if (ip6rd->relay_prefixlen)
1118 relay_prefix = ip6rd->relay_prefix &
1119 htonl(0xffffffffUL <<
1120 (32 - ip6rd->relay_prefixlen));
1121 else
1122 relay_prefix = 0;
1123 if (relay_prefix != ip6rd->relay_prefix)
1124 return -EINVAL;
1125
1126 t->ip6rd.prefix = prefix;
1127 t->ip6rd.relay_prefix = relay_prefix;
1128 t->ip6rd.prefixlen = ip6rd->prefixlen;
1129 t->ip6rd.relay_prefixlen = ip6rd->relay_prefixlen;
1130 ip_tunnel_dst_reset_all(t);
1131 netdev_state_change(t->dev);
1132 return 0;
1133 }
1134 #endif
1135
1136 static int
1137 ipip6_tunnel_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
1138 {
1139 int err = 0;
1140 struct ip_tunnel_parm p;
1141 struct ip_tunnel_prl prl;
1142 struct ip_tunnel *t = netdev_priv(dev);
1143 struct net *net = t->net;
1144 struct sit_net *sitn = net_generic(net, sit_net_id);
1145 #ifdef CONFIG_IPV6_SIT_6RD
1146 struct ip_tunnel_6rd ip6rd;
1147 #endif
1148
1149 switch (cmd) {
1150 case SIOCGETTUNNEL:
1151 #ifdef CONFIG_IPV6_SIT_6RD
1152 case SIOCGET6RD:
1153 #endif
1154 if (dev == sitn->fb_tunnel_dev) {
1155 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) {
1156 err = -EFAULT;
1157 break;
1158 }
1159 t = ipip6_tunnel_locate(net, &p, 0);
1160 if (!t)
1161 t = netdev_priv(dev);
1162 }
1163
1164 err = -EFAULT;
1165 if (cmd == SIOCGETTUNNEL) {
1166 memcpy(&p, &t->parms, sizeof(p));
1167 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p,
1168 sizeof(p)))
1169 goto done;
1170 #ifdef CONFIG_IPV6_SIT_6RD
1171 } else {
1172 ip6rd.prefix = t->ip6rd.prefix;
1173 ip6rd.relay_prefix = t->ip6rd.relay_prefix;
1174 ip6rd.prefixlen = t->ip6rd.prefixlen;
1175 ip6rd.relay_prefixlen = t->ip6rd.relay_prefixlen;
1176 if (copy_to_user(ifr->ifr_ifru.ifru_data, &ip6rd,
1177 sizeof(ip6rd)))
1178 goto done;
1179 #endif
1180 }
1181 err = 0;
1182 break;
1183
1184 case SIOCADDTUNNEL:
1185 case SIOCCHGTUNNEL:
1186 err = -EPERM;
1187 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1188 goto done;
1189
1190 err = -EFAULT;
1191 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
1192 goto done;
1193
1194 err = -EINVAL;
1195 if (p.iph.protocol != IPPROTO_IPV6 &&
1196 p.iph.protocol != IPPROTO_IPIP &&
1197 p.iph.protocol != 0)
1198 goto done;
1199 if (p.iph.version != 4 ||
1200 p.iph.ihl != 5 || (p.iph.frag_off&htons(~IP_DF)))
1201 goto done;
1202 if (p.iph.ttl)
1203 p.iph.frag_off |= htons(IP_DF);
1204
1205 t = ipip6_tunnel_locate(net, &p, cmd == SIOCADDTUNNEL);
1206
1207 if (dev != sitn->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) {
1208 if (t) {
1209 if (t->dev != dev) {
1210 err = -EEXIST;
1211 break;
1212 }
1213 } else {
1214 if (((dev->flags&IFF_POINTOPOINT) && !p.iph.daddr) ||
1215 (!(dev->flags&IFF_POINTOPOINT) && p.iph.daddr)) {
1216 err = -EINVAL;
1217 break;
1218 }
1219 t = netdev_priv(dev);
1220 }
1221
1222 ipip6_tunnel_update(t, &p);
1223 }
1224
1225 if (t) {
1226 err = 0;
1227 if (copy_to_user(ifr->ifr_ifru.ifru_data, &t->parms, sizeof(p)))
1228 err = -EFAULT;
1229 } else
1230 err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
1231 break;
1232
1233 case SIOCDELTUNNEL:
1234 err = -EPERM;
1235 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1236 goto done;
1237
1238 if (dev == sitn->fb_tunnel_dev) {
1239 err = -EFAULT;
1240 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
1241 goto done;
1242 err = -ENOENT;
1243 t = ipip6_tunnel_locate(net, &p, 0);
1244 if (!t)
1245 goto done;
1246 err = -EPERM;
1247 if (t == netdev_priv(sitn->fb_tunnel_dev))
1248 goto done;
1249 dev = t->dev;
1250 }
1251 unregister_netdevice(dev);
1252 err = 0;
1253 break;
1254
1255 case SIOCGETPRL:
1256 err = -EINVAL;
1257 if (dev == sitn->fb_tunnel_dev)
1258 goto done;
1259 err = ipip6_tunnel_get_prl(t, ifr->ifr_ifru.ifru_data);
1260 break;
1261
1262 case SIOCADDPRL:
1263 case SIOCDELPRL:
1264 case SIOCCHGPRL:
1265 err = -EPERM;
1266 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1267 goto done;
1268 err = -EINVAL;
1269 if (dev == sitn->fb_tunnel_dev)
1270 goto done;
1271 err = -EFAULT;
1272 if (copy_from_user(&prl, ifr->ifr_ifru.ifru_data, sizeof(prl)))
1273 goto done;
1274
1275 switch (cmd) {
1276 case SIOCDELPRL:
1277 err = ipip6_tunnel_del_prl(t, &prl);
1278 break;
1279 case SIOCADDPRL:
1280 case SIOCCHGPRL:
1281 err = ipip6_tunnel_add_prl(t, &prl, cmd == SIOCCHGPRL);
1282 break;
1283 }
1284 ip_tunnel_dst_reset_all(t);
1285 netdev_state_change(dev);
1286 break;
1287
1288 #ifdef CONFIG_IPV6_SIT_6RD
1289 case SIOCADD6RD:
1290 case SIOCCHG6RD:
1291 case SIOCDEL6RD:
1292 err = -EPERM;
1293 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1294 goto done;
1295
1296 err = -EFAULT;
1297 if (copy_from_user(&ip6rd, ifr->ifr_ifru.ifru_data,
1298 sizeof(ip6rd)))
1299 goto done;
1300
1301 if (cmd != SIOCDEL6RD) {
1302 err = ipip6_tunnel_update_6rd(t, &ip6rd);
1303 if (err < 0)
1304 goto done;
1305 } else
1306 ipip6_tunnel_clone_6rd(dev, sitn);
1307
1308 err = 0;
1309 break;
1310 #endif
1311
1312 default:
1313 err = -EINVAL;
1314 }
1315
1316 done:
1317 return err;
1318 }
1319
1320 static int ipip6_tunnel_change_mtu(struct net_device *dev, int new_mtu)
1321 {
1322 struct ip_tunnel *tunnel = netdev_priv(dev);
1323 int t_hlen = tunnel->hlen + sizeof(struct iphdr);
1324
1325 if (new_mtu < IPV6_MIN_MTU || new_mtu > 0xFFF8 - t_hlen)
1326 return -EINVAL;
1327 dev->mtu = new_mtu;
1328 return 0;
1329 }
1330
1331 static const struct net_device_ops ipip6_netdev_ops = {
1332 .ndo_init = ipip6_tunnel_init,
1333 .ndo_uninit = ipip6_tunnel_uninit,
1334 .ndo_start_xmit = sit_tunnel_xmit,
1335 .ndo_do_ioctl = ipip6_tunnel_ioctl,
1336 .ndo_change_mtu = ipip6_tunnel_change_mtu,
1337 .ndo_get_stats64 = ip_tunnel_get_stats64,
1338 .ndo_get_iflink = ip_tunnel_get_iflink,
1339 };
1340
1341 static void ipip6_dev_free(struct net_device *dev)
1342 {
1343 struct ip_tunnel *tunnel = netdev_priv(dev);
1344
1345 free_percpu(tunnel->dst_cache);
1346 free_percpu(dev->tstats);
1347 free_netdev(dev);
1348 }
1349
1350 #define SIT_FEATURES (NETIF_F_SG | \
1351 NETIF_F_FRAGLIST | \
1352 NETIF_F_HIGHDMA | \
1353 NETIF_F_GSO_SOFTWARE | \
1354 NETIF_F_HW_CSUM)
1355
1356 static void ipip6_tunnel_setup(struct net_device *dev)
1357 {
1358 struct ip_tunnel *tunnel = netdev_priv(dev);
1359 int t_hlen = tunnel->hlen + sizeof(struct iphdr);
1360
1361 dev->netdev_ops = &ipip6_netdev_ops;
1362 dev->destructor = ipip6_dev_free;
1363
1364 dev->type = ARPHRD_SIT;
1365 dev->hard_header_len = LL_MAX_HEADER + t_hlen;
1366 dev->mtu = ETH_DATA_LEN - t_hlen;
1367 dev->flags = IFF_NOARP;
1368 netif_keep_dst(dev);
1369 dev->addr_len = 4;
1370 dev->features |= NETIF_F_LLTX;
1371 dev->features |= SIT_FEATURES;
1372 dev->hw_features |= SIT_FEATURES;
1373 }
1374
1375 static int ipip6_tunnel_init(struct net_device *dev)
1376 {
1377 struct ip_tunnel *tunnel = netdev_priv(dev);
1378
1379 tunnel->dev = dev;
1380 tunnel->net = dev_net(dev);
1381 strcpy(tunnel->parms.name, dev->name);
1382
1383 ipip6_tunnel_bind_dev(dev);
1384 dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
1385 if (!dev->tstats)
1386 return -ENOMEM;
1387
1388 tunnel->dst_cache = alloc_percpu(struct ip_tunnel_dst);
1389 if (!tunnel->dst_cache) {
1390 free_percpu(dev->tstats);
1391 return -ENOMEM;
1392 }
1393
1394 return 0;
1395 }
1396
1397 static void __net_init ipip6_fb_tunnel_init(struct net_device *dev)
1398 {
1399 struct ip_tunnel *tunnel = netdev_priv(dev);
1400 struct iphdr *iph = &tunnel->parms.iph;
1401 struct net *net = dev_net(dev);
1402 struct sit_net *sitn = net_generic(net, sit_net_id);
1403
1404 iph->version = 4;
1405 iph->protocol = IPPROTO_IPV6;
1406 iph->ihl = 5;
1407 iph->ttl = 64;
1408
1409 dev_hold(dev);
1410 rcu_assign_pointer(sitn->tunnels_wc[0], tunnel);
1411 }
1412
1413 static int ipip6_validate(struct nlattr *tb[], struct nlattr *data[])
1414 {
1415 u8 proto;
1416
1417 if (!data || !data[IFLA_IPTUN_PROTO])
1418 return 0;
1419
1420 proto = nla_get_u8(data[IFLA_IPTUN_PROTO]);
1421 if (proto != IPPROTO_IPV6 &&
1422 proto != IPPROTO_IPIP &&
1423 proto != 0)
1424 return -EINVAL;
1425
1426 return 0;
1427 }
1428
1429 static void ipip6_netlink_parms(struct nlattr *data[],
1430 struct ip_tunnel_parm *parms)
1431 {
1432 memset(parms, 0, sizeof(*parms));
1433
1434 parms->iph.version = 4;
1435 parms->iph.protocol = IPPROTO_IPV6;
1436 parms->iph.ihl = 5;
1437 parms->iph.ttl = 64;
1438
1439 if (!data)
1440 return;
1441
1442 if (data[IFLA_IPTUN_LINK])
1443 parms->link = nla_get_u32(data[IFLA_IPTUN_LINK]);
1444
1445 if (data[IFLA_IPTUN_LOCAL])
1446 parms->iph.saddr = nla_get_be32(data[IFLA_IPTUN_LOCAL]);
1447
1448 if (data[IFLA_IPTUN_REMOTE])
1449 parms->iph.daddr = nla_get_be32(data[IFLA_IPTUN_REMOTE]);
1450
1451 if (data[IFLA_IPTUN_TTL]) {
1452 parms->iph.ttl = nla_get_u8(data[IFLA_IPTUN_TTL]);
1453 if (parms->iph.ttl)
1454 parms->iph.frag_off = htons(IP_DF);
1455 }
1456
1457 if (data[IFLA_IPTUN_TOS])
1458 parms->iph.tos = nla_get_u8(data[IFLA_IPTUN_TOS]);
1459
1460 if (!data[IFLA_IPTUN_PMTUDISC] || nla_get_u8(data[IFLA_IPTUN_PMTUDISC]))
1461 parms->iph.frag_off = htons(IP_DF);
1462
1463 if (data[IFLA_IPTUN_FLAGS])
1464 parms->i_flags = nla_get_be16(data[IFLA_IPTUN_FLAGS]);
1465
1466 if (data[IFLA_IPTUN_PROTO])
1467 parms->iph.protocol = nla_get_u8(data[IFLA_IPTUN_PROTO]);
1468
1469 }
1470
1471 /* This function returns true when ENCAP attributes are present in the nl msg */
1472 static bool ipip6_netlink_encap_parms(struct nlattr *data[],
1473 struct ip_tunnel_encap *ipencap)
1474 {
1475 bool ret = false;
1476
1477 memset(ipencap, 0, sizeof(*ipencap));
1478
1479 if (!data)
1480 return ret;
1481
1482 if (data[IFLA_IPTUN_ENCAP_TYPE]) {
1483 ret = true;
1484 ipencap->type = nla_get_u16(data[IFLA_IPTUN_ENCAP_TYPE]);
1485 }
1486
1487 if (data[IFLA_IPTUN_ENCAP_FLAGS]) {
1488 ret = true;
1489 ipencap->flags = nla_get_u16(data[IFLA_IPTUN_ENCAP_FLAGS]);
1490 }
1491
1492 if (data[IFLA_IPTUN_ENCAP_SPORT]) {
1493 ret = true;
1494 ipencap->sport = nla_get_be16(data[IFLA_IPTUN_ENCAP_SPORT]);
1495 }
1496
1497 if (data[IFLA_IPTUN_ENCAP_DPORT]) {
1498 ret = true;
1499 ipencap->dport = nla_get_be16(data[IFLA_IPTUN_ENCAP_DPORT]);
1500 }
1501
1502 return ret;
1503 }
1504
1505 #ifdef CONFIG_IPV6_SIT_6RD
1506 /* This function returns true when 6RD attributes are present in the nl msg */
1507 static bool ipip6_netlink_6rd_parms(struct nlattr *data[],
1508 struct ip_tunnel_6rd *ip6rd)
1509 {
1510 bool ret = false;
1511 memset(ip6rd, 0, sizeof(*ip6rd));
1512
1513 if (!data)
1514 return ret;
1515
1516 if (data[IFLA_IPTUN_6RD_PREFIX]) {
1517 ret = true;
1518 ip6rd->prefix = nla_get_in6_addr(data[IFLA_IPTUN_6RD_PREFIX]);
1519 }
1520
1521 if (data[IFLA_IPTUN_6RD_RELAY_PREFIX]) {
1522 ret = true;
1523 ip6rd->relay_prefix =
1524 nla_get_be32(data[IFLA_IPTUN_6RD_RELAY_PREFIX]);
1525 }
1526
1527 if (data[IFLA_IPTUN_6RD_PREFIXLEN]) {
1528 ret = true;
1529 ip6rd->prefixlen = nla_get_u16(data[IFLA_IPTUN_6RD_PREFIXLEN]);
1530 }
1531
1532 if (data[IFLA_IPTUN_6RD_RELAY_PREFIXLEN]) {
1533 ret = true;
1534 ip6rd->relay_prefixlen =
1535 nla_get_u16(data[IFLA_IPTUN_6RD_RELAY_PREFIXLEN]);
1536 }
1537
1538 return ret;
1539 }
1540 #endif
1541
1542 static int ipip6_newlink(struct net *src_net, struct net_device *dev,
1543 struct nlattr *tb[], struct nlattr *data[])
1544 {
1545 struct net *net = dev_net(dev);
1546 struct ip_tunnel *nt;
1547 struct ip_tunnel_encap ipencap;
1548 #ifdef CONFIG_IPV6_SIT_6RD
1549 struct ip_tunnel_6rd ip6rd;
1550 #endif
1551 int err;
1552
1553 nt = netdev_priv(dev);
1554
1555 if (ipip6_netlink_encap_parms(data, &ipencap)) {
1556 err = ip_tunnel_encap_setup(nt, &ipencap);
1557 if (err < 0)
1558 return err;
1559 }
1560
1561 ipip6_netlink_parms(data, &nt->parms);
1562
1563 if (ipip6_tunnel_locate(net, &nt->parms, 0))
1564 return -EEXIST;
1565
1566 err = ipip6_tunnel_create(dev);
1567 if (err < 0)
1568 return err;
1569
1570 #ifdef CONFIG_IPV6_SIT_6RD
1571 if (ipip6_netlink_6rd_parms(data, &ip6rd))
1572 err = ipip6_tunnel_update_6rd(nt, &ip6rd);
1573 #endif
1574
1575 return err;
1576 }
1577
1578 static int ipip6_changelink(struct net_device *dev, struct nlattr *tb[],
1579 struct nlattr *data[])
1580 {
1581 struct ip_tunnel *t = netdev_priv(dev);
1582 struct ip_tunnel_parm p;
1583 struct ip_tunnel_encap ipencap;
1584 struct net *net = t->net;
1585 struct sit_net *sitn = net_generic(net, sit_net_id);
1586 #ifdef CONFIG_IPV6_SIT_6RD
1587 struct ip_tunnel_6rd ip6rd;
1588 #endif
1589 int err;
1590
1591 if (dev == sitn->fb_tunnel_dev)
1592 return -EINVAL;
1593
1594 if (ipip6_netlink_encap_parms(data, &ipencap)) {
1595 err = ip_tunnel_encap_setup(t, &ipencap);
1596 if (err < 0)
1597 return err;
1598 }
1599
1600 ipip6_netlink_parms(data, &p);
1601
1602 if (((dev->flags & IFF_POINTOPOINT) && !p.iph.daddr) ||
1603 (!(dev->flags & IFF_POINTOPOINT) && p.iph.daddr))
1604 return -EINVAL;
1605
1606 t = ipip6_tunnel_locate(net, &p, 0);
1607
1608 if (t) {
1609 if (t->dev != dev)
1610 return -EEXIST;
1611 } else
1612 t = netdev_priv(dev);
1613
1614 ipip6_tunnel_update(t, &p);
1615
1616 #ifdef CONFIG_IPV6_SIT_6RD
1617 if (ipip6_netlink_6rd_parms(data, &ip6rd))
1618 return ipip6_tunnel_update_6rd(t, &ip6rd);
1619 #endif
1620
1621 return 0;
1622 }
1623
1624 static size_t ipip6_get_size(const struct net_device *dev)
1625 {
1626 return
1627 /* IFLA_IPTUN_LINK */
1628 nla_total_size(4) +
1629 /* IFLA_IPTUN_LOCAL */
1630 nla_total_size(4) +
1631 /* IFLA_IPTUN_REMOTE */
1632 nla_total_size(4) +
1633 /* IFLA_IPTUN_TTL */
1634 nla_total_size(1) +
1635 /* IFLA_IPTUN_TOS */
1636 nla_total_size(1) +
1637 /* IFLA_IPTUN_PMTUDISC */
1638 nla_total_size(1) +
1639 /* IFLA_IPTUN_FLAGS */
1640 nla_total_size(2) +
1641 /* IFLA_IPTUN_PROTO */
1642 nla_total_size(1) +
1643 #ifdef CONFIG_IPV6_SIT_6RD
1644 /* IFLA_IPTUN_6RD_PREFIX */
1645 nla_total_size(sizeof(struct in6_addr)) +
1646 /* IFLA_IPTUN_6RD_RELAY_PREFIX */
1647 nla_total_size(4) +
1648 /* IFLA_IPTUN_6RD_PREFIXLEN */
1649 nla_total_size(2) +
1650 /* IFLA_IPTUN_6RD_RELAY_PREFIXLEN */
1651 nla_total_size(2) +
1652 #endif
1653 /* IFLA_IPTUN_ENCAP_TYPE */
1654 nla_total_size(2) +
1655 /* IFLA_IPTUN_ENCAP_FLAGS */
1656 nla_total_size(2) +
1657 /* IFLA_IPTUN_ENCAP_SPORT */
1658 nla_total_size(2) +
1659 /* IFLA_IPTUN_ENCAP_DPORT */
1660 nla_total_size(2) +
1661 0;
1662 }
1663
1664 static int ipip6_fill_info(struct sk_buff *skb, const struct net_device *dev)
1665 {
1666 struct ip_tunnel *tunnel = netdev_priv(dev);
1667 struct ip_tunnel_parm *parm = &tunnel->parms;
1668
1669 if (nla_put_u32(skb, IFLA_IPTUN_LINK, parm->link) ||
1670 nla_put_in_addr(skb, IFLA_IPTUN_LOCAL, parm->iph.saddr) ||
1671 nla_put_in_addr(skb, IFLA_IPTUN_REMOTE, parm->iph.daddr) ||
1672 nla_put_u8(skb, IFLA_IPTUN_TTL, parm->iph.ttl) ||
1673 nla_put_u8(skb, IFLA_IPTUN_TOS, parm->iph.tos) ||
1674 nla_put_u8(skb, IFLA_IPTUN_PMTUDISC,
1675 !!(parm->iph.frag_off & htons(IP_DF))) ||
1676 nla_put_u8(skb, IFLA_IPTUN_PROTO, parm->iph.protocol) ||
1677 nla_put_be16(skb, IFLA_IPTUN_FLAGS, parm->i_flags))
1678 goto nla_put_failure;
1679
1680 #ifdef CONFIG_IPV6_SIT_6RD
1681 if (nla_put_in6_addr(skb, IFLA_IPTUN_6RD_PREFIX,
1682 &tunnel->ip6rd.prefix) ||
1683 nla_put_in_addr(skb, IFLA_IPTUN_6RD_RELAY_PREFIX,
1684 tunnel->ip6rd.relay_prefix) ||
1685 nla_put_u16(skb, IFLA_IPTUN_6RD_PREFIXLEN,
1686 tunnel->ip6rd.prefixlen) ||
1687 nla_put_u16(skb, IFLA_IPTUN_6RD_RELAY_PREFIXLEN,
1688 tunnel->ip6rd.relay_prefixlen))
1689 goto nla_put_failure;
1690 #endif
1691
1692 if (nla_put_u16(skb, IFLA_IPTUN_ENCAP_TYPE,
1693 tunnel->encap.type) ||
1694 nla_put_be16(skb, IFLA_IPTUN_ENCAP_SPORT,
1695 tunnel->encap.sport) ||
1696 nla_put_be16(skb, IFLA_IPTUN_ENCAP_DPORT,
1697 tunnel->encap.dport) ||
1698 nla_put_u16(skb, IFLA_IPTUN_ENCAP_FLAGS,
1699 tunnel->encap.flags))
1700 goto nla_put_failure;
1701
1702 return 0;
1703
1704 nla_put_failure:
1705 return -EMSGSIZE;
1706 }
1707
1708 static const struct nla_policy ipip6_policy[IFLA_IPTUN_MAX + 1] = {
1709 [IFLA_IPTUN_LINK] = { .type = NLA_U32 },
1710 [IFLA_IPTUN_LOCAL] = { .type = NLA_U32 },
1711 [IFLA_IPTUN_REMOTE] = { .type = NLA_U32 },
1712 [IFLA_IPTUN_TTL] = { .type = NLA_U8 },
1713 [IFLA_IPTUN_TOS] = { .type = NLA_U8 },
1714 [IFLA_IPTUN_PMTUDISC] = { .type = NLA_U8 },
1715 [IFLA_IPTUN_FLAGS] = { .type = NLA_U16 },
1716 [IFLA_IPTUN_PROTO] = { .type = NLA_U8 },
1717 #ifdef CONFIG_IPV6_SIT_6RD
1718 [IFLA_IPTUN_6RD_PREFIX] = { .len = sizeof(struct in6_addr) },
1719 [IFLA_IPTUN_6RD_RELAY_PREFIX] = { .type = NLA_U32 },
1720 [IFLA_IPTUN_6RD_PREFIXLEN] = { .type = NLA_U16 },
1721 [IFLA_IPTUN_6RD_RELAY_PREFIXLEN] = { .type = NLA_U16 },
1722 #endif
1723 [IFLA_IPTUN_ENCAP_TYPE] = { .type = NLA_U16 },
1724 [IFLA_IPTUN_ENCAP_FLAGS] = { .type = NLA_U16 },
1725 [IFLA_IPTUN_ENCAP_SPORT] = { .type = NLA_U16 },
1726 [IFLA_IPTUN_ENCAP_DPORT] = { .type = NLA_U16 },
1727 };
1728
1729 static void ipip6_dellink(struct net_device *dev, struct list_head *head)
1730 {
1731 struct net *net = dev_net(dev);
1732 struct sit_net *sitn = net_generic(net, sit_net_id);
1733
1734 if (dev != sitn->fb_tunnel_dev)
1735 unregister_netdevice_queue(dev, head);
1736 }
1737
1738 static struct rtnl_link_ops sit_link_ops __read_mostly = {
1739 .kind = "sit",
1740 .maxtype = IFLA_IPTUN_MAX,
1741 .policy = ipip6_policy,
1742 .priv_size = sizeof(struct ip_tunnel),
1743 .setup = ipip6_tunnel_setup,
1744 .validate = ipip6_validate,
1745 .newlink = ipip6_newlink,
1746 .changelink = ipip6_changelink,
1747 .get_size = ipip6_get_size,
1748 .fill_info = ipip6_fill_info,
1749 .dellink = ipip6_dellink,
1750 .get_link_net = ip_tunnel_get_link_net,
1751 };
1752
1753 static struct xfrm_tunnel sit_handler __read_mostly = {
1754 .handler = ipip6_rcv,
1755 .err_handler = ipip6_err,
1756 .priority = 1,
1757 };
1758
1759 static struct xfrm_tunnel ipip_handler __read_mostly = {
1760 .handler = ipip_rcv,
1761 .err_handler = ipip6_err,
1762 .priority = 2,
1763 };
1764
1765 static void __net_exit sit_destroy_tunnels(struct net *net,
1766 struct list_head *head)
1767 {
1768 struct sit_net *sitn = net_generic(net, sit_net_id);
1769 struct net_device *dev, *aux;
1770 int prio;
1771
1772 for_each_netdev_safe(net, dev, aux)
1773 if (dev->rtnl_link_ops == &sit_link_ops)
1774 unregister_netdevice_queue(dev, head);
1775
1776 for (prio = 1; prio < 4; prio++) {
1777 int h;
1778 for (h = 0; h < HASH_SIZE; h++) {
1779 struct ip_tunnel *t;
1780
1781 t = rtnl_dereference(sitn->tunnels[prio][h]);
1782 while (t) {
1783 /* If dev is in the same netns, it has already
1784 * been added to the list by the previous loop.
1785 */
1786 if (!net_eq(dev_net(t->dev), net))
1787 unregister_netdevice_queue(t->dev,
1788 head);
1789 t = rtnl_dereference(t->next);
1790 }
1791 }
1792 }
1793 }
1794
1795 static int __net_init sit_init_net(struct net *net)
1796 {
1797 struct sit_net *sitn = net_generic(net, sit_net_id);
1798 struct ip_tunnel *t;
1799 int err;
1800
1801 sitn->tunnels[0] = sitn->tunnels_wc;
1802 sitn->tunnels[1] = sitn->tunnels_l;
1803 sitn->tunnels[2] = sitn->tunnels_r;
1804 sitn->tunnels[3] = sitn->tunnels_r_l;
1805
1806 sitn->fb_tunnel_dev = alloc_netdev(sizeof(struct ip_tunnel), "sit0",
1807 NET_NAME_UNKNOWN,
1808 ipip6_tunnel_setup);
1809 if (!sitn->fb_tunnel_dev) {
1810 err = -ENOMEM;
1811 goto err_alloc_dev;
1812 }
1813 dev_net_set(sitn->fb_tunnel_dev, net);
1814 sitn->fb_tunnel_dev->rtnl_link_ops = &sit_link_ops;
1815 /* FB netdevice is special: we have one, and only one per netns.
1816 * Allowing to move it to another netns is clearly unsafe.
1817 */
1818 sitn->fb_tunnel_dev->features |= NETIF_F_NETNS_LOCAL;
1819
1820 err = register_netdev(sitn->fb_tunnel_dev);
1821 if (err)
1822 goto err_reg_dev;
1823
1824 ipip6_tunnel_clone_6rd(sitn->fb_tunnel_dev, sitn);
1825 ipip6_fb_tunnel_init(sitn->fb_tunnel_dev);
1826
1827 t = netdev_priv(sitn->fb_tunnel_dev);
1828
1829 strcpy(t->parms.name, sitn->fb_tunnel_dev->name);
1830 return 0;
1831
1832 err_reg_dev:
1833 ipip6_dev_free(sitn->fb_tunnel_dev);
1834 err_alloc_dev:
1835 return err;
1836 }
1837
1838 static void __net_exit sit_exit_net(struct net *net)
1839 {
1840 LIST_HEAD(list);
1841
1842 rtnl_lock();
1843 sit_destroy_tunnels(net, &list);
1844 unregister_netdevice_many(&list);
1845 rtnl_unlock();
1846 }
1847
1848 static struct pernet_operations sit_net_ops = {
1849 .init = sit_init_net,
1850 .exit = sit_exit_net,
1851 .id = &sit_net_id,
1852 .size = sizeof(struct sit_net),
1853 };
1854
1855 static void __exit sit_cleanup(void)
1856 {
1857 rtnl_link_unregister(&sit_link_ops);
1858 xfrm4_tunnel_deregister(&sit_handler, AF_INET6);
1859 xfrm4_tunnel_deregister(&ipip_handler, AF_INET);
1860
1861 unregister_pernet_device(&sit_net_ops);
1862 rcu_barrier(); /* Wait for completion of call_rcu()'s */
1863 }
1864
1865 static int __init sit_init(void)
1866 {
1867 int err;
1868
1869 pr_info("IPv6 over IPv4 tunneling driver\n");
1870
1871 err = register_pernet_device(&sit_net_ops);
1872 if (err < 0)
1873 return err;
1874 err = xfrm4_tunnel_register(&sit_handler, AF_INET6);
1875 if (err < 0) {
1876 pr_info("%s: can't register ip6ip4\n", __func__);
1877 goto xfrm_tunnel_failed;
1878 }
1879 err = xfrm4_tunnel_register(&ipip_handler, AF_INET);
1880 if (err < 0) {
1881 pr_info("%s: can't register ip4ip4\n", __func__);
1882 goto xfrm_tunnel4_failed;
1883 }
1884 err = rtnl_link_register(&sit_link_ops);
1885 if (err < 0)
1886 goto rtnl_link_failed;
1887
1888 out:
1889 return err;
1890
1891 rtnl_link_failed:
1892 xfrm4_tunnel_deregister(&ipip_handler, AF_INET);
1893 xfrm_tunnel4_failed:
1894 xfrm4_tunnel_deregister(&sit_handler, AF_INET6);
1895 xfrm_tunnel_failed:
1896 unregister_pernet_device(&sit_net_ops);
1897 goto out;
1898 }
1899
1900 module_init(sit_init);
1901 module_exit(sit_cleanup);
1902 MODULE_LICENSE("GPL");
1903 MODULE_ALIAS_RTNL_LINK("sit");
1904 MODULE_ALIAS_NETDEV("sit0");
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