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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->iflink == 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->iflink == 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->iflink == t->parms.link) &&
117 (t->dev->flags & IFF_UP))
118 return t;
119 }
120 t = rcu_dereference(sitn->tunnels_wc[0]);
121 if ((t != NULL) && (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 err = ipip6_tunnel_init(dev);
199 if (err < 0)
200 goto out;
201 ipip6_tunnel_clone_6rd(dev, sitn);
202
203 if ((__force u16)t->parms.i_flags & SIT_ISATAP)
204 dev->priv_flags |= IFF_ISATAP;
205
206 err = register_netdevice(dev);
207 if (err < 0)
208 goto out;
209
210 strcpy(t->parms.name, dev->name);
211 dev->rtnl_link_ops = &sit_link_ops;
212
213 dev_hold(dev);
214
215 ipip6_tunnel_link(sitn, t);
216 return 0;
217
218 out:
219 return err;
220 }
221
222 static struct ip_tunnel *ipip6_tunnel_locate(struct net *net,
223 struct ip_tunnel_parm *parms, int create)
224 {
225 __be32 remote = parms->iph.daddr;
226 __be32 local = parms->iph.saddr;
227 struct ip_tunnel *t, *nt;
228 struct ip_tunnel __rcu **tp;
229 struct net_device *dev;
230 char name[IFNAMSIZ];
231 struct sit_net *sitn = net_generic(net, sit_net_id);
232
233 for (tp = __ipip6_bucket(sitn, parms);
234 (t = rtnl_dereference(*tp)) != NULL;
235 tp = &t->next) {
236 if (local == t->parms.iph.saddr &&
237 remote == t->parms.iph.daddr &&
238 parms->link == t->parms.link) {
239 if (create)
240 return NULL;
241 else
242 return t;
243 }
244 }
245 if (!create)
246 goto failed;
247
248 if (parms->name[0])
249 strlcpy(name, parms->name, IFNAMSIZ);
250 else
251 strcpy(name, "sit%d");
252
253 dev = alloc_netdev(sizeof(*t), name, ipip6_tunnel_setup);
254 if (dev == NULL)
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 dev_put(dev);
479 }
480
481
482 static int ipip6_err(struct sk_buff *skb, u32 info)
483 {
484
485 /* All the routers (except for Linux) return only
486 8 bytes of packet payload. It means, that precise relaying of
487 ICMP in the real Internet is absolutely infeasible.
488 */
489 const struct iphdr *iph = (const struct iphdr *)skb->data;
490 const int type = icmp_hdr(skb)->type;
491 const int code = icmp_hdr(skb)->code;
492 struct ip_tunnel *t;
493 int err;
494
495 switch (type) {
496 default:
497 case ICMP_PARAMETERPROB:
498 return 0;
499
500 case ICMP_DEST_UNREACH:
501 switch (code) {
502 case ICMP_SR_FAILED:
503 case ICMP_PORT_UNREACH:
504 /* Impossible event. */
505 return 0;
506 default:
507 /* All others are translated to HOST_UNREACH.
508 rfc2003 contains "deep thoughts" about NET_UNREACH,
509 I believe they are just ether pollution. --ANK
510 */
511 break;
512 }
513 break;
514 case ICMP_TIME_EXCEEDED:
515 if (code != ICMP_EXC_TTL)
516 return 0;
517 break;
518 case ICMP_REDIRECT:
519 break;
520 }
521
522 err = -ENOENT;
523
524 t = ipip6_tunnel_lookup(dev_net(skb->dev),
525 skb->dev,
526 iph->daddr,
527 iph->saddr);
528 if (t == NULL)
529 goto out;
530
531 if (type == ICMP_DEST_UNREACH && code == ICMP_FRAG_NEEDED) {
532 ipv4_update_pmtu(skb, dev_net(skb->dev), info,
533 t->dev->ifindex, 0, IPPROTO_IPV6, 0);
534 err = 0;
535 goto out;
536 }
537 if (type == ICMP_REDIRECT) {
538 ipv4_redirect(skb, dev_net(skb->dev), t->dev->ifindex, 0,
539 IPPROTO_IPV6, 0);
540 err = 0;
541 goto out;
542 }
543
544 if (t->parms.iph.daddr == 0)
545 goto out;
546
547 err = 0;
548 if (t->parms.iph.ttl == 0 && type == ICMP_TIME_EXCEEDED)
549 goto out;
550
551 if (time_before(jiffies, t->err_time + IPTUNNEL_ERR_TIMEO))
552 t->err_count++;
553 else
554 t->err_count = 1;
555 t->err_time = jiffies;
556 out:
557 return err;
558 }
559
560 static inline bool is_spoofed_6rd(struct ip_tunnel *tunnel, const __be32 v4addr,
561 const struct in6_addr *v6addr)
562 {
563 __be32 v4embed = 0;
564 if (check_6rd(tunnel, v6addr, &v4embed) && v4addr != v4embed)
565 return true;
566 return false;
567 }
568
569 static int ipip6_rcv(struct sk_buff *skb)
570 {
571 const struct iphdr *iph = ip_hdr(skb);
572 struct ip_tunnel *tunnel;
573 int err;
574
575 tunnel = ipip6_tunnel_lookup(dev_net(skb->dev), skb->dev,
576 iph->saddr, iph->daddr);
577 if (tunnel != NULL) {
578 struct pcpu_tstats *tstats;
579
580 if (tunnel->parms.iph.protocol != IPPROTO_IPV6 &&
581 tunnel->parms.iph.protocol != 0)
582 goto out;
583
584 skb->mac_header = skb->network_header;
585 skb_reset_network_header(skb);
586 IPCB(skb)->flags = 0;
587 skb->protocol = htons(ETH_P_IPV6);
588
589 if (tunnel->dev->priv_flags & IFF_ISATAP) {
590 if (!isatap_chksrc(skb, iph, tunnel)) {
591 tunnel->dev->stats.rx_errors++;
592 goto out;
593 }
594 } else if (!(tunnel->dev->flags&IFF_POINTOPOINT)) {
595 if (is_spoofed_6rd(tunnel, iph->saddr,
596 &ipv6_hdr(skb)->saddr) ||
597 is_spoofed_6rd(tunnel, iph->daddr,
598 &ipv6_hdr(skb)->daddr)) {
599 tunnel->dev->stats.rx_errors++;
600 goto out;
601 }
602 }
603
604 __skb_tunnel_rx(skb, tunnel->dev, tunnel->net);
605
606 err = IP_ECN_decapsulate(iph, skb);
607 if (unlikely(err)) {
608 if (log_ecn_error)
609 net_info_ratelimited("non-ECT from %pI4 with TOS=%#x\n",
610 &iph->saddr, iph->tos);
611 if (err > 1) {
612 ++tunnel->dev->stats.rx_frame_errors;
613 ++tunnel->dev->stats.rx_errors;
614 goto out;
615 }
616 }
617
618 tstats = this_cpu_ptr(tunnel->dev->tstats);
619 tstats->rx_packets++;
620 tstats->rx_bytes += skb->len;
621
622 netif_rx(skb);
623
624 return 0;
625 }
626
627 /* no tunnel matched, let upstream know, ipsec may handle it */
628 return 1;
629 out:
630 kfree_skb(skb);
631 return 0;
632 }
633
634 static const struct tnl_ptk_info tpi = {
635 /* no tunnel info required for ipip. */
636 .proto = htons(ETH_P_IP),
637 };
638
639 static int ipip_rcv(struct sk_buff *skb)
640 {
641 const struct iphdr *iph;
642 struct ip_tunnel *tunnel;
643
644 iph = ip_hdr(skb);
645 tunnel = ipip6_tunnel_lookup(dev_net(skb->dev), skb->dev,
646 iph->saddr, iph->daddr);
647 if (tunnel != NULL) {
648 if (tunnel->parms.iph.protocol != IPPROTO_IPIP &&
649 tunnel->parms.iph.protocol != 0)
650 goto drop;
651
652 if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb))
653 goto drop;
654 if (iptunnel_pull_header(skb, 0, tpi.proto))
655 goto drop;
656 return ip_tunnel_rcv(tunnel, skb, &tpi, log_ecn_error);
657 }
658
659 return 1;
660
661 drop:
662 kfree_skb(skb);
663 return 0;
664 }
665
666 /*
667 * If the IPv6 address comes from 6rd / 6to4 (RFC 3056) addr space this function
668 * stores the embedded IPv4 address in v4dst and returns true.
669 */
670 static bool check_6rd(struct ip_tunnel *tunnel, const struct in6_addr *v6dst,
671 __be32 *v4dst)
672 {
673 #ifdef CONFIG_IPV6_SIT_6RD
674 if (ipv6_prefix_equal(v6dst, &tunnel->ip6rd.prefix,
675 tunnel->ip6rd.prefixlen)) {
676 unsigned int pbw0, pbi0;
677 int pbi1;
678 u32 d;
679
680 pbw0 = tunnel->ip6rd.prefixlen >> 5;
681 pbi0 = tunnel->ip6rd.prefixlen & 0x1f;
682
683 d = (ntohl(v6dst->s6_addr32[pbw0]) << pbi0) >>
684 tunnel->ip6rd.relay_prefixlen;
685
686 pbi1 = pbi0 - tunnel->ip6rd.relay_prefixlen;
687 if (pbi1 > 0)
688 d |= ntohl(v6dst->s6_addr32[pbw0 + 1]) >>
689 (32 - pbi1);
690
691 *v4dst = tunnel->ip6rd.relay_prefix | htonl(d);
692 return true;
693 }
694 #else
695 if (v6dst->s6_addr16[0] == htons(0x2002)) {
696 /* 6to4 v6 addr has 16 bits prefix, 32 v4addr, 16 SLA, ... */
697 memcpy(v4dst, &v6dst->s6_addr16[1], 4);
698 return true;
699 }
700 #endif
701 return false;
702 }
703
704 static inline __be32 try_6rd(struct ip_tunnel *tunnel,
705 const struct in6_addr *v6dst)
706 {
707 __be32 dst = 0;
708 check_6rd(tunnel, v6dst, &dst);
709 return dst;
710 }
711
712 /*
713 * This function assumes it is being called from dev_queue_xmit()
714 * and that skb is filled properly by that function.
715 */
716
717 static netdev_tx_t ipip6_tunnel_xmit(struct sk_buff *skb,
718 struct net_device *dev)
719 {
720 struct ip_tunnel *tunnel = netdev_priv(dev);
721 const struct iphdr *tiph = &tunnel->parms.iph;
722 const struct ipv6hdr *iph6 = ipv6_hdr(skb);
723 u8 tos = tunnel->parms.iph.tos;
724 __be16 df = tiph->frag_off;
725 struct rtable *rt; /* Route to the other host */
726 struct net_device *tdev; /* Device to other host */
727 unsigned int max_headroom; /* The extra header space needed */
728 __be32 dst = tiph->daddr;
729 struct flowi4 fl4;
730 int mtu;
731 const struct in6_addr *addr6;
732 int addr_type;
733 u8 ttl;
734 int err;
735
736 if (skb->protocol != htons(ETH_P_IPV6))
737 goto tx_error;
738
739 if (tos == 1)
740 tos = ipv6_get_dsfield(iph6);
741
742 /* ISATAP (RFC4214) - must come before 6to4 */
743 if (dev->priv_flags & IFF_ISATAP) {
744 struct neighbour *neigh = NULL;
745 bool do_tx_error = false;
746
747 if (skb_dst(skb))
748 neigh = dst_neigh_lookup(skb_dst(skb), &iph6->daddr);
749
750 if (neigh == NULL) {
751 net_dbg_ratelimited("sit: nexthop == NULL\n");
752 goto tx_error;
753 }
754
755 addr6 = (const struct in6_addr *)&neigh->primary_key;
756 addr_type = ipv6_addr_type(addr6);
757
758 if ((addr_type & IPV6_ADDR_UNICAST) &&
759 ipv6_addr_is_isatap(addr6))
760 dst = addr6->s6_addr32[3];
761 else
762 do_tx_error = true;
763
764 neigh_release(neigh);
765 if (do_tx_error)
766 goto tx_error;
767 }
768
769 if (!dst)
770 dst = try_6rd(tunnel, &iph6->daddr);
771
772 if (!dst) {
773 struct neighbour *neigh = NULL;
774 bool do_tx_error = false;
775
776 if (skb_dst(skb))
777 neigh = dst_neigh_lookup(skb_dst(skb), &iph6->daddr);
778
779 if (neigh == NULL) {
780 net_dbg_ratelimited("sit: nexthop == NULL\n");
781 goto tx_error;
782 }
783
784 addr6 = (const struct in6_addr *)&neigh->primary_key;
785 addr_type = ipv6_addr_type(addr6);
786
787 if (addr_type == IPV6_ADDR_ANY) {
788 addr6 = &ipv6_hdr(skb)->daddr;
789 addr_type = ipv6_addr_type(addr6);
790 }
791
792 if ((addr_type & IPV6_ADDR_COMPATv4) != 0)
793 dst = addr6->s6_addr32[3];
794 else
795 do_tx_error = true;
796
797 neigh_release(neigh);
798 if (do_tx_error)
799 goto tx_error;
800 }
801
802 rt = ip_route_output_ports(tunnel->net, &fl4, NULL,
803 dst, tiph->saddr,
804 0, 0,
805 IPPROTO_IPV6, RT_TOS(tos),
806 tunnel->parms.link);
807 if (IS_ERR(rt)) {
808 dev->stats.tx_carrier_errors++;
809 goto tx_error_icmp;
810 }
811 if (rt->rt_type != RTN_UNICAST) {
812 ip_rt_put(rt);
813 dev->stats.tx_carrier_errors++;
814 goto tx_error_icmp;
815 }
816 tdev = rt->dst.dev;
817
818 if (tdev == dev) {
819 ip_rt_put(rt);
820 dev->stats.collisions++;
821 goto tx_error;
822 }
823
824 if (df) {
825 mtu = dst_mtu(&rt->dst) - sizeof(struct iphdr);
826
827 if (mtu < 68) {
828 dev->stats.collisions++;
829 ip_rt_put(rt);
830 goto tx_error;
831 }
832
833 if (mtu < IPV6_MIN_MTU) {
834 mtu = IPV6_MIN_MTU;
835 df = 0;
836 }
837
838 if (tunnel->parms.iph.daddr && skb_dst(skb))
839 skb_dst(skb)->ops->update_pmtu(skb_dst(skb), NULL, skb, mtu);
840
841 if (skb->len > mtu) {
842 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
843 ip_rt_put(rt);
844 goto tx_error;
845 }
846 }
847
848 if (tunnel->err_count > 0) {
849 if (time_before(jiffies,
850 tunnel->err_time + IPTUNNEL_ERR_TIMEO)) {
851 tunnel->err_count--;
852 dst_link_failure(skb);
853 } else
854 tunnel->err_count = 0;
855 }
856
857 /*
858 * Okay, now see if we can stuff it in the buffer as-is.
859 */
860 max_headroom = LL_RESERVED_SPACE(tdev)+sizeof(struct iphdr);
861
862 if (skb_headroom(skb) < max_headroom || skb_shared(skb) ||
863 (skb_cloned(skb) && !skb_clone_writable(skb, 0))) {
864 struct sk_buff *new_skb = skb_realloc_headroom(skb, max_headroom);
865 if (!new_skb) {
866 ip_rt_put(rt);
867 dev->stats.tx_dropped++;
868 dev_kfree_skb(skb);
869 return NETDEV_TX_OK;
870 }
871 if (skb->sk)
872 skb_set_owner_w(new_skb, skb->sk);
873 dev_kfree_skb(skb);
874 skb = new_skb;
875 iph6 = ipv6_hdr(skb);
876 }
877 ttl = tiph->ttl;
878 if (ttl == 0)
879 ttl = iph6->hop_limit;
880 tos = INET_ECN_encapsulate(tos, ipv6_get_dsfield(iph6));
881
882 if (likely(!skb->encapsulation)) {
883 skb_reset_inner_headers(skb);
884 skb->encapsulation = 1;
885 }
886
887 err = iptunnel_xmit(rt, skb, fl4.saddr, fl4.daddr, IPPROTO_IPV6, tos,
888 ttl, df, !net_eq(tunnel->net, dev_net(dev)));
889 iptunnel_xmit_stats(err, &dev->stats, dev->tstats);
890 return NETDEV_TX_OK;
891
892 tx_error_icmp:
893 dst_link_failure(skb);
894 tx_error:
895 dev->stats.tx_errors++;
896 dev_kfree_skb(skb);
897 return NETDEV_TX_OK;
898 }
899
900 static netdev_tx_t ipip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev)
901 {
902 struct ip_tunnel *tunnel = netdev_priv(dev);
903 const struct iphdr *tiph = &tunnel->parms.iph;
904
905 if (likely(!skb->encapsulation)) {
906 skb_reset_inner_headers(skb);
907 skb->encapsulation = 1;
908 }
909
910 ip_tunnel_xmit(skb, dev, tiph, IPPROTO_IPIP);
911 return NETDEV_TX_OK;
912 }
913
914 static netdev_tx_t sit_tunnel_xmit(struct sk_buff *skb,
915 struct net_device *dev)
916 {
917 switch (skb->protocol) {
918 case htons(ETH_P_IP):
919 ipip_tunnel_xmit(skb, dev);
920 break;
921 case htons(ETH_P_IPV6):
922 ipip6_tunnel_xmit(skb, dev);
923 break;
924 default:
925 goto tx_err;
926 }
927
928 return NETDEV_TX_OK;
929
930 tx_err:
931 dev->stats.tx_errors++;
932 dev_kfree_skb(skb);
933 return NETDEV_TX_OK;
934
935 }
936
937 static void ipip6_tunnel_bind_dev(struct net_device *dev)
938 {
939 struct net_device *tdev = NULL;
940 struct ip_tunnel *tunnel;
941 const struct iphdr *iph;
942 struct flowi4 fl4;
943
944 tunnel = netdev_priv(dev);
945 iph = &tunnel->parms.iph;
946
947 if (iph->daddr) {
948 struct rtable *rt = ip_route_output_ports(tunnel->net, &fl4,
949 NULL,
950 iph->daddr, iph->saddr,
951 0, 0,
952 IPPROTO_IPV6,
953 RT_TOS(iph->tos),
954 tunnel->parms.link);
955
956 if (!IS_ERR(rt)) {
957 tdev = rt->dst.dev;
958 ip_rt_put(rt);
959 }
960 dev->flags |= IFF_POINTOPOINT;
961 }
962
963 if (!tdev && tunnel->parms.link)
964 tdev = __dev_get_by_index(tunnel->net, tunnel->parms.link);
965
966 if (tdev) {
967 dev->hard_header_len = tdev->hard_header_len + sizeof(struct iphdr);
968 dev->mtu = tdev->mtu - sizeof(struct iphdr);
969 if (dev->mtu < IPV6_MIN_MTU)
970 dev->mtu = IPV6_MIN_MTU;
971 }
972 dev->iflink = tunnel->parms.link;
973 }
974
975 static void ipip6_tunnel_update(struct ip_tunnel *t, struct ip_tunnel_parm *p)
976 {
977 struct net *net = t->net;
978 struct sit_net *sitn = net_generic(net, sit_net_id);
979
980 ipip6_tunnel_unlink(sitn, t);
981 synchronize_net();
982 t->parms.iph.saddr = p->iph.saddr;
983 t->parms.iph.daddr = p->iph.daddr;
984 memcpy(t->dev->dev_addr, &p->iph.saddr, 4);
985 memcpy(t->dev->broadcast, &p->iph.daddr, 4);
986 ipip6_tunnel_link(sitn, t);
987 t->parms.iph.ttl = p->iph.ttl;
988 t->parms.iph.tos = p->iph.tos;
989 if (t->parms.link != p->link) {
990 t->parms.link = p->link;
991 ipip6_tunnel_bind_dev(t->dev);
992 }
993 netdev_state_change(t->dev);
994 }
995
996 #ifdef CONFIG_IPV6_SIT_6RD
997 static int ipip6_tunnel_update_6rd(struct ip_tunnel *t,
998 struct ip_tunnel_6rd *ip6rd)
999 {
1000 struct in6_addr prefix;
1001 __be32 relay_prefix;
1002
1003 if (ip6rd->relay_prefixlen > 32 ||
1004 ip6rd->prefixlen + (32 - ip6rd->relay_prefixlen) > 64)
1005 return -EINVAL;
1006
1007 ipv6_addr_prefix(&prefix, &ip6rd->prefix, ip6rd->prefixlen);
1008 if (!ipv6_addr_equal(&prefix, &ip6rd->prefix))
1009 return -EINVAL;
1010 if (ip6rd->relay_prefixlen)
1011 relay_prefix = ip6rd->relay_prefix &
1012 htonl(0xffffffffUL <<
1013 (32 - ip6rd->relay_prefixlen));
1014 else
1015 relay_prefix = 0;
1016 if (relay_prefix != ip6rd->relay_prefix)
1017 return -EINVAL;
1018
1019 t->ip6rd.prefix = prefix;
1020 t->ip6rd.relay_prefix = relay_prefix;
1021 t->ip6rd.prefixlen = ip6rd->prefixlen;
1022 t->ip6rd.relay_prefixlen = ip6rd->relay_prefixlen;
1023 netdev_state_change(t->dev);
1024 return 0;
1025 }
1026 #endif
1027
1028 static int
1029 ipip6_tunnel_ioctl (struct net_device *dev, struct ifreq *ifr, int cmd)
1030 {
1031 int err = 0;
1032 struct ip_tunnel_parm p;
1033 struct ip_tunnel_prl prl;
1034 struct ip_tunnel *t;
1035 struct net *net = dev_net(dev);
1036 struct sit_net *sitn = net_generic(net, sit_net_id);
1037 #ifdef CONFIG_IPV6_SIT_6RD
1038 struct ip_tunnel_6rd ip6rd;
1039 #endif
1040
1041 switch (cmd) {
1042 case SIOCGETTUNNEL:
1043 #ifdef CONFIG_IPV6_SIT_6RD
1044 case SIOCGET6RD:
1045 #endif
1046 t = NULL;
1047 if (dev == sitn->fb_tunnel_dev) {
1048 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) {
1049 err = -EFAULT;
1050 break;
1051 }
1052 t = ipip6_tunnel_locate(net, &p, 0);
1053 }
1054 if (t == NULL)
1055 t = netdev_priv(dev);
1056
1057 err = -EFAULT;
1058 if (cmd == SIOCGETTUNNEL) {
1059 memcpy(&p, &t->parms, sizeof(p));
1060 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p,
1061 sizeof(p)))
1062 goto done;
1063 #ifdef CONFIG_IPV6_SIT_6RD
1064 } else {
1065 ip6rd.prefix = t->ip6rd.prefix;
1066 ip6rd.relay_prefix = t->ip6rd.relay_prefix;
1067 ip6rd.prefixlen = t->ip6rd.prefixlen;
1068 ip6rd.relay_prefixlen = t->ip6rd.relay_prefixlen;
1069 if (copy_to_user(ifr->ifr_ifru.ifru_data, &ip6rd,
1070 sizeof(ip6rd)))
1071 goto done;
1072 #endif
1073 }
1074 err = 0;
1075 break;
1076
1077 case SIOCADDTUNNEL:
1078 case SIOCCHGTUNNEL:
1079 err = -EPERM;
1080 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1081 goto done;
1082
1083 err = -EFAULT;
1084 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
1085 goto done;
1086
1087 err = -EINVAL;
1088 if (p.iph.protocol != IPPROTO_IPV6 &&
1089 p.iph.protocol != IPPROTO_IPIP &&
1090 p.iph.protocol != 0)
1091 goto done;
1092 if (p.iph.version != 4 ||
1093 p.iph.ihl != 5 || (p.iph.frag_off&htons(~IP_DF)))
1094 goto done;
1095 if (p.iph.ttl)
1096 p.iph.frag_off |= htons(IP_DF);
1097
1098 t = ipip6_tunnel_locate(net, &p, cmd == SIOCADDTUNNEL);
1099
1100 if (dev != sitn->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) {
1101 if (t != NULL) {
1102 if (t->dev != dev) {
1103 err = -EEXIST;
1104 break;
1105 }
1106 } else {
1107 if (((dev->flags&IFF_POINTOPOINT) && !p.iph.daddr) ||
1108 (!(dev->flags&IFF_POINTOPOINT) && p.iph.daddr)) {
1109 err = -EINVAL;
1110 break;
1111 }
1112 t = netdev_priv(dev);
1113 }
1114
1115 ipip6_tunnel_update(t, &p);
1116 }
1117
1118 if (t) {
1119 err = 0;
1120 if (copy_to_user(ifr->ifr_ifru.ifru_data, &t->parms, sizeof(p)))
1121 err = -EFAULT;
1122 } else
1123 err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
1124 break;
1125
1126 case SIOCDELTUNNEL:
1127 err = -EPERM;
1128 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1129 goto done;
1130
1131 if (dev == sitn->fb_tunnel_dev) {
1132 err = -EFAULT;
1133 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
1134 goto done;
1135 err = -ENOENT;
1136 if ((t = ipip6_tunnel_locate(net, &p, 0)) == NULL)
1137 goto done;
1138 err = -EPERM;
1139 if (t == netdev_priv(sitn->fb_tunnel_dev))
1140 goto done;
1141 dev = t->dev;
1142 }
1143 unregister_netdevice(dev);
1144 err = 0;
1145 break;
1146
1147 case SIOCGETPRL:
1148 err = -EINVAL;
1149 if (dev == sitn->fb_tunnel_dev)
1150 goto done;
1151 err = -ENOENT;
1152 if (!(t = netdev_priv(dev)))
1153 goto done;
1154 err = ipip6_tunnel_get_prl(t, ifr->ifr_ifru.ifru_data);
1155 break;
1156
1157 case SIOCADDPRL:
1158 case SIOCDELPRL:
1159 case SIOCCHGPRL:
1160 err = -EPERM;
1161 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1162 goto done;
1163 err = -EINVAL;
1164 if (dev == sitn->fb_tunnel_dev)
1165 goto done;
1166 err = -EFAULT;
1167 if (copy_from_user(&prl, ifr->ifr_ifru.ifru_data, sizeof(prl)))
1168 goto done;
1169 err = -ENOENT;
1170 if (!(t = netdev_priv(dev)))
1171 goto done;
1172
1173 switch (cmd) {
1174 case SIOCDELPRL:
1175 err = ipip6_tunnel_del_prl(t, &prl);
1176 break;
1177 case SIOCADDPRL:
1178 case SIOCCHGPRL:
1179 err = ipip6_tunnel_add_prl(t, &prl, cmd == SIOCCHGPRL);
1180 break;
1181 }
1182 netdev_state_change(dev);
1183 break;
1184
1185 #ifdef CONFIG_IPV6_SIT_6RD
1186 case SIOCADD6RD:
1187 case SIOCCHG6RD:
1188 case SIOCDEL6RD:
1189 err = -EPERM;
1190 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1191 goto done;
1192
1193 err = -EFAULT;
1194 if (copy_from_user(&ip6rd, ifr->ifr_ifru.ifru_data,
1195 sizeof(ip6rd)))
1196 goto done;
1197
1198 t = netdev_priv(dev);
1199
1200 if (cmd != SIOCDEL6RD) {
1201 err = ipip6_tunnel_update_6rd(t, &ip6rd);
1202 if (err < 0)
1203 goto done;
1204 } else
1205 ipip6_tunnel_clone_6rd(dev, sitn);
1206
1207 err = 0;
1208 break;
1209 #endif
1210
1211 default:
1212 err = -EINVAL;
1213 }
1214
1215 done:
1216 return err;
1217 }
1218
1219 static int ipip6_tunnel_change_mtu(struct net_device *dev, int new_mtu)
1220 {
1221 if (new_mtu < IPV6_MIN_MTU || new_mtu > 0xFFF8 - sizeof(struct iphdr))
1222 return -EINVAL;
1223 dev->mtu = new_mtu;
1224 return 0;
1225 }
1226
1227 static const struct net_device_ops ipip6_netdev_ops = {
1228 .ndo_uninit = ipip6_tunnel_uninit,
1229 .ndo_start_xmit = sit_tunnel_xmit,
1230 .ndo_do_ioctl = ipip6_tunnel_ioctl,
1231 .ndo_change_mtu = ipip6_tunnel_change_mtu,
1232 .ndo_get_stats64 = ip_tunnel_get_stats64,
1233 };
1234
1235 static void ipip6_dev_free(struct net_device *dev)
1236 {
1237 free_percpu(dev->tstats);
1238 free_netdev(dev);
1239 }
1240
1241 static void ipip6_tunnel_setup(struct net_device *dev)
1242 {
1243 dev->netdev_ops = &ipip6_netdev_ops;
1244 dev->destructor = ipip6_dev_free;
1245
1246 dev->type = ARPHRD_SIT;
1247 dev->hard_header_len = LL_MAX_HEADER + sizeof(struct iphdr);
1248 dev->mtu = ETH_DATA_LEN - sizeof(struct iphdr);
1249 dev->flags = IFF_NOARP;
1250 dev->priv_flags &= ~IFF_XMIT_DST_RELEASE;
1251 dev->iflink = 0;
1252 dev->addr_len = 4;
1253 dev->features |= NETIF_F_LLTX;
1254 }
1255
1256 static int ipip6_tunnel_init(struct net_device *dev)
1257 {
1258 struct ip_tunnel *tunnel = netdev_priv(dev);
1259
1260 tunnel->dev = dev;
1261 tunnel->net = dev_net(dev);
1262
1263 memcpy(dev->dev_addr, &tunnel->parms.iph.saddr, 4);
1264 memcpy(dev->broadcast, &tunnel->parms.iph.daddr, 4);
1265
1266 ipip6_tunnel_bind_dev(dev);
1267 dev->tstats = alloc_percpu(struct pcpu_tstats);
1268 if (!dev->tstats)
1269 return -ENOMEM;
1270
1271 return 0;
1272 }
1273
1274 static int __net_init ipip6_fb_tunnel_init(struct net_device *dev)
1275 {
1276 struct ip_tunnel *tunnel = netdev_priv(dev);
1277 struct iphdr *iph = &tunnel->parms.iph;
1278 struct net *net = dev_net(dev);
1279 struct sit_net *sitn = net_generic(net, sit_net_id);
1280
1281 tunnel->dev = dev;
1282 tunnel->net = dev_net(dev);
1283 strcpy(tunnel->parms.name, dev->name);
1284
1285 iph->version = 4;
1286 iph->protocol = IPPROTO_IPV6;
1287 iph->ihl = 5;
1288 iph->ttl = 64;
1289
1290 dev->tstats = alloc_percpu(struct pcpu_tstats);
1291 if (!dev->tstats)
1292 return -ENOMEM;
1293 dev_hold(dev);
1294 rcu_assign_pointer(sitn->tunnels_wc[0], tunnel);
1295 return 0;
1296 }
1297
1298 static int ipip6_validate(struct nlattr *tb[], struct nlattr *data[])
1299 {
1300 u8 proto;
1301
1302 if (!data || !data[IFLA_IPTUN_PROTO])
1303 return 0;
1304
1305 proto = nla_get_u8(data[IFLA_IPTUN_PROTO]);
1306 if (proto != IPPROTO_IPV6 &&
1307 proto != IPPROTO_IPIP &&
1308 proto != 0)
1309 return -EINVAL;
1310
1311 return 0;
1312 }
1313
1314 static void ipip6_netlink_parms(struct nlattr *data[],
1315 struct ip_tunnel_parm *parms)
1316 {
1317 memset(parms, 0, sizeof(*parms));
1318
1319 parms->iph.version = 4;
1320 parms->iph.protocol = IPPROTO_IPV6;
1321 parms->iph.ihl = 5;
1322 parms->iph.ttl = 64;
1323
1324 if (!data)
1325 return;
1326
1327 if (data[IFLA_IPTUN_LINK])
1328 parms->link = nla_get_u32(data[IFLA_IPTUN_LINK]);
1329
1330 if (data[IFLA_IPTUN_LOCAL])
1331 parms->iph.saddr = nla_get_be32(data[IFLA_IPTUN_LOCAL]);
1332
1333 if (data[IFLA_IPTUN_REMOTE])
1334 parms->iph.daddr = nla_get_be32(data[IFLA_IPTUN_REMOTE]);
1335
1336 if (data[IFLA_IPTUN_TTL]) {
1337 parms->iph.ttl = nla_get_u8(data[IFLA_IPTUN_TTL]);
1338 if (parms->iph.ttl)
1339 parms->iph.frag_off = htons(IP_DF);
1340 }
1341
1342 if (data[IFLA_IPTUN_TOS])
1343 parms->iph.tos = nla_get_u8(data[IFLA_IPTUN_TOS]);
1344
1345 if (!data[IFLA_IPTUN_PMTUDISC] || nla_get_u8(data[IFLA_IPTUN_PMTUDISC]))
1346 parms->iph.frag_off = htons(IP_DF);
1347
1348 if (data[IFLA_IPTUN_FLAGS])
1349 parms->i_flags = nla_get_be16(data[IFLA_IPTUN_FLAGS]);
1350
1351 if (data[IFLA_IPTUN_PROTO])
1352 parms->iph.protocol = nla_get_u8(data[IFLA_IPTUN_PROTO]);
1353
1354 }
1355
1356 #ifdef CONFIG_IPV6_SIT_6RD
1357 /* This function returns true when 6RD attributes are present in the nl msg */
1358 static bool ipip6_netlink_6rd_parms(struct nlattr *data[],
1359 struct ip_tunnel_6rd *ip6rd)
1360 {
1361 bool ret = false;
1362 memset(ip6rd, 0, sizeof(*ip6rd));
1363
1364 if (!data)
1365 return ret;
1366
1367 if (data[IFLA_IPTUN_6RD_PREFIX]) {
1368 ret = true;
1369 nla_memcpy(&ip6rd->prefix, data[IFLA_IPTUN_6RD_PREFIX],
1370 sizeof(struct in6_addr));
1371 }
1372
1373 if (data[IFLA_IPTUN_6RD_RELAY_PREFIX]) {
1374 ret = true;
1375 ip6rd->relay_prefix =
1376 nla_get_be32(data[IFLA_IPTUN_6RD_RELAY_PREFIX]);
1377 }
1378
1379 if (data[IFLA_IPTUN_6RD_PREFIXLEN]) {
1380 ret = true;
1381 ip6rd->prefixlen = nla_get_u16(data[IFLA_IPTUN_6RD_PREFIXLEN]);
1382 }
1383
1384 if (data[IFLA_IPTUN_6RD_RELAY_PREFIXLEN]) {
1385 ret = true;
1386 ip6rd->relay_prefixlen =
1387 nla_get_u16(data[IFLA_IPTUN_6RD_RELAY_PREFIXLEN]);
1388 }
1389
1390 return ret;
1391 }
1392 #endif
1393
1394 static int ipip6_newlink(struct net *src_net, struct net_device *dev,
1395 struct nlattr *tb[], struct nlattr *data[])
1396 {
1397 struct net *net = dev_net(dev);
1398 struct ip_tunnel *nt;
1399 #ifdef CONFIG_IPV6_SIT_6RD
1400 struct ip_tunnel_6rd ip6rd;
1401 #endif
1402 int err;
1403
1404 nt = netdev_priv(dev);
1405 ipip6_netlink_parms(data, &nt->parms);
1406
1407 if (ipip6_tunnel_locate(net, &nt->parms, 0))
1408 return -EEXIST;
1409
1410 err = ipip6_tunnel_create(dev);
1411 if (err < 0)
1412 return err;
1413
1414 #ifdef CONFIG_IPV6_SIT_6RD
1415 if (ipip6_netlink_6rd_parms(data, &ip6rd))
1416 err = ipip6_tunnel_update_6rd(nt, &ip6rd);
1417 #endif
1418
1419 return err;
1420 }
1421
1422 static int ipip6_changelink(struct net_device *dev, struct nlattr *tb[],
1423 struct nlattr *data[])
1424 {
1425 struct ip_tunnel *t = netdev_priv(dev);
1426 struct ip_tunnel_parm p;
1427 struct net *net = t->net;
1428 struct sit_net *sitn = net_generic(net, sit_net_id);
1429 #ifdef CONFIG_IPV6_SIT_6RD
1430 struct ip_tunnel_6rd ip6rd;
1431 #endif
1432
1433 if (dev == sitn->fb_tunnel_dev)
1434 return -EINVAL;
1435
1436 ipip6_netlink_parms(data, &p);
1437
1438 if (((dev->flags & IFF_POINTOPOINT) && !p.iph.daddr) ||
1439 (!(dev->flags & IFF_POINTOPOINT) && p.iph.daddr))
1440 return -EINVAL;
1441
1442 t = ipip6_tunnel_locate(net, &p, 0);
1443
1444 if (t) {
1445 if (t->dev != dev)
1446 return -EEXIST;
1447 } else
1448 t = netdev_priv(dev);
1449
1450 ipip6_tunnel_update(t, &p);
1451
1452 #ifdef CONFIG_IPV6_SIT_6RD
1453 if (ipip6_netlink_6rd_parms(data, &ip6rd))
1454 return ipip6_tunnel_update_6rd(t, &ip6rd);
1455 #endif
1456
1457 return 0;
1458 }
1459
1460 static size_t ipip6_get_size(const struct net_device *dev)
1461 {
1462 return
1463 /* IFLA_IPTUN_LINK */
1464 nla_total_size(4) +
1465 /* IFLA_IPTUN_LOCAL */
1466 nla_total_size(4) +
1467 /* IFLA_IPTUN_REMOTE */
1468 nla_total_size(4) +
1469 /* IFLA_IPTUN_TTL */
1470 nla_total_size(1) +
1471 /* IFLA_IPTUN_TOS */
1472 nla_total_size(1) +
1473 /* IFLA_IPTUN_PMTUDISC */
1474 nla_total_size(1) +
1475 /* IFLA_IPTUN_FLAGS */
1476 nla_total_size(2) +
1477 /* IFLA_IPTUN_PROTO */
1478 nla_total_size(1) +
1479 #ifdef CONFIG_IPV6_SIT_6RD
1480 /* IFLA_IPTUN_6RD_PREFIX */
1481 nla_total_size(sizeof(struct in6_addr)) +
1482 /* IFLA_IPTUN_6RD_RELAY_PREFIX */
1483 nla_total_size(4) +
1484 /* IFLA_IPTUN_6RD_PREFIXLEN */
1485 nla_total_size(2) +
1486 /* IFLA_IPTUN_6RD_RELAY_PREFIXLEN */
1487 nla_total_size(2) +
1488 #endif
1489 0;
1490 }
1491
1492 static int ipip6_fill_info(struct sk_buff *skb, const struct net_device *dev)
1493 {
1494 struct ip_tunnel *tunnel = netdev_priv(dev);
1495 struct ip_tunnel_parm *parm = &tunnel->parms;
1496
1497 if (nla_put_u32(skb, IFLA_IPTUN_LINK, parm->link) ||
1498 nla_put_be32(skb, IFLA_IPTUN_LOCAL, parm->iph.saddr) ||
1499 nla_put_be32(skb, IFLA_IPTUN_REMOTE, parm->iph.daddr) ||
1500 nla_put_u8(skb, IFLA_IPTUN_TTL, parm->iph.ttl) ||
1501 nla_put_u8(skb, IFLA_IPTUN_TOS, parm->iph.tos) ||
1502 nla_put_u8(skb, IFLA_IPTUN_PMTUDISC,
1503 !!(parm->iph.frag_off & htons(IP_DF))) ||
1504 nla_put_u8(skb, IFLA_IPTUN_PROTO, parm->iph.protocol) ||
1505 nla_put_be16(skb, IFLA_IPTUN_FLAGS, parm->i_flags))
1506 goto nla_put_failure;
1507
1508 #ifdef CONFIG_IPV6_SIT_6RD
1509 if (nla_put(skb, IFLA_IPTUN_6RD_PREFIX, sizeof(struct in6_addr),
1510 &tunnel->ip6rd.prefix) ||
1511 nla_put_be32(skb, IFLA_IPTUN_6RD_RELAY_PREFIX,
1512 tunnel->ip6rd.relay_prefix) ||
1513 nla_put_u16(skb, IFLA_IPTUN_6RD_PREFIXLEN,
1514 tunnel->ip6rd.prefixlen) ||
1515 nla_put_u16(skb, IFLA_IPTUN_6RD_RELAY_PREFIXLEN,
1516 tunnel->ip6rd.relay_prefixlen))
1517 goto nla_put_failure;
1518 #endif
1519
1520 return 0;
1521
1522 nla_put_failure:
1523 return -EMSGSIZE;
1524 }
1525
1526 static const struct nla_policy ipip6_policy[IFLA_IPTUN_MAX + 1] = {
1527 [IFLA_IPTUN_LINK] = { .type = NLA_U32 },
1528 [IFLA_IPTUN_LOCAL] = { .type = NLA_U32 },
1529 [IFLA_IPTUN_REMOTE] = { .type = NLA_U32 },
1530 [IFLA_IPTUN_TTL] = { .type = NLA_U8 },
1531 [IFLA_IPTUN_TOS] = { .type = NLA_U8 },
1532 [IFLA_IPTUN_PMTUDISC] = { .type = NLA_U8 },
1533 [IFLA_IPTUN_FLAGS] = { .type = NLA_U16 },
1534 [IFLA_IPTUN_PROTO] = { .type = NLA_U8 },
1535 #ifdef CONFIG_IPV6_SIT_6RD
1536 [IFLA_IPTUN_6RD_PREFIX] = { .len = sizeof(struct in6_addr) },
1537 [IFLA_IPTUN_6RD_RELAY_PREFIX] = { .type = NLA_U32 },
1538 [IFLA_IPTUN_6RD_PREFIXLEN] = { .type = NLA_U16 },
1539 [IFLA_IPTUN_6RD_RELAY_PREFIXLEN] = { .type = NLA_U16 },
1540 #endif
1541 };
1542
1543 static struct rtnl_link_ops sit_link_ops __read_mostly = {
1544 .kind = "sit",
1545 .maxtype = IFLA_IPTUN_MAX,
1546 .policy = ipip6_policy,
1547 .priv_size = sizeof(struct ip_tunnel),
1548 .setup = ipip6_tunnel_setup,
1549 .validate = ipip6_validate,
1550 .newlink = ipip6_newlink,
1551 .changelink = ipip6_changelink,
1552 .get_size = ipip6_get_size,
1553 .fill_info = ipip6_fill_info,
1554 };
1555
1556 static struct xfrm_tunnel sit_handler __read_mostly = {
1557 .handler = ipip6_rcv,
1558 .err_handler = ipip6_err,
1559 .priority = 1,
1560 };
1561
1562 static struct xfrm_tunnel ipip_handler __read_mostly = {
1563 .handler = ipip_rcv,
1564 .err_handler = ipip6_err,
1565 .priority = 2,
1566 };
1567
1568 static void __net_exit sit_destroy_tunnels(struct sit_net *sitn, struct list_head *head)
1569 {
1570 struct net *net = dev_net(sitn->fb_tunnel_dev);
1571 struct net_device *dev, *aux;
1572 int prio;
1573
1574 for_each_netdev_safe(net, dev, aux)
1575 if (dev->rtnl_link_ops == &sit_link_ops)
1576 unregister_netdevice_queue(dev, head);
1577
1578 for (prio = 1; prio < 4; prio++) {
1579 int h;
1580 for (h = 0; h < HASH_SIZE; h++) {
1581 struct ip_tunnel *t;
1582
1583 t = rtnl_dereference(sitn->tunnels[prio][h]);
1584 while (t != NULL) {
1585 /* If dev is in the same netns, it has already
1586 * been added to the list by the previous loop.
1587 */
1588 if (!net_eq(dev_net(t->dev), net))
1589 unregister_netdevice_queue(t->dev,
1590 head);
1591 t = rtnl_dereference(t->next);
1592 }
1593 }
1594 }
1595 }
1596
1597 static int __net_init sit_init_net(struct net *net)
1598 {
1599 struct sit_net *sitn = net_generic(net, sit_net_id);
1600 struct ip_tunnel *t;
1601 int err;
1602
1603 sitn->tunnels[0] = sitn->tunnels_wc;
1604 sitn->tunnels[1] = sitn->tunnels_l;
1605 sitn->tunnels[2] = sitn->tunnels_r;
1606 sitn->tunnels[3] = sitn->tunnels_r_l;
1607
1608 sitn->fb_tunnel_dev = alloc_netdev(sizeof(struct ip_tunnel), "sit0",
1609 ipip6_tunnel_setup);
1610 if (!sitn->fb_tunnel_dev) {
1611 err = -ENOMEM;
1612 goto err_alloc_dev;
1613 }
1614 dev_net_set(sitn->fb_tunnel_dev, net);
1615 /* FB netdevice is special: we have one, and only one per netns.
1616 * Allowing to move it to another netns is clearly unsafe.
1617 */
1618 sitn->fb_tunnel_dev->features |= NETIF_F_NETNS_LOCAL;
1619
1620 err = ipip6_fb_tunnel_init(sitn->fb_tunnel_dev);
1621 if (err)
1622 goto err_dev_free;
1623
1624 ipip6_tunnel_clone_6rd(sitn->fb_tunnel_dev, sitn);
1625
1626 if ((err = register_netdev(sitn->fb_tunnel_dev)))
1627 goto err_reg_dev;
1628
1629 t = netdev_priv(sitn->fb_tunnel_dev);
1630
1631 strcpy(t->parms.name, sitn->fb_tunnel_dev->name);
1632 return 0;
1633
1634 err_reg_dev:
1635 dev_put(sitn->fb_tunnel_dev);
1636 err_dev_free:
1637 ipip6_dev_free(sitn->fb_tunnel_dev);
1638 err_alloc_dev:
1639 return err;
1640 }
1641
1642 static void __net_exit sit_exit_net(struct net *net)
1643 {
1644 struct sit_net *sitn = net_generic(net, sit_net_id);
1645 LIST_HEAD(list);
1646
1647 rtnl_lock();
1648 sit_destroy_tunnels(sitn, &list);
1649 unregister_netdevice_queue(sitn->fb_tunnel_dev, &list);
1650 unregister_netdevice_many(&list);
1651 rtnl_unlock();
1652 }
1653
1654 static struct pernet_operations sit_net_ops = {
1655 .init = sit_init_net,
1656 .exit = sit_exit_net,
1657 .id = &sit_net_id,
1658 .size = sizeof(struct sit_net),
1659 };
1660
1661 static void __exit sit_cleanup(void)
1662 {
1663 rtnl_link_unregister(&sit_link_ops);
1664 xfrm4_tunnel_deregister(&sit_handler, AF_INET6);
1665 xfrm4_tunnel_deregister(&ipip_handler, AF_INET);
1666
1667 unregister_pernet_device(&sit_net_ops);
1668 rcu_barrier(); /* Wait for completion of call_rcu()'s */
1669 }
1670
1671 static int __init sit_init(void)
1672 {
1673 int err;
1674
1675 pr_info("IPv6 over IPv4 tunneling driver\n");
1676
1677 err = register_pernet_device(&sit_net_ops);
1678 if (err < 0)
1679 return err;
1680 err = xfrm4_tunnel_register(&sit_handler, AF_INET6);
1681 if (err < 0) {
1682 pr_info("%s: can't register ip6ip4\n", __func__);
1683 goto xfrm_tunnel_failed;
1684 }
1685 err = xfrm4_tunnel_register(&ipip_handler, AF_INET);
1686 if (err < 0) {
1687 pr_info("%s: can't register ip4ip4\n", __func__);
1688 goto xfrm_tunnel4_failed;
1689 }
1690 err = rtnl_link_register(&sit_link_ops);
1691 if (err < 0)
1692 goto rtnl_link_failed;
1693
1694 out:
1695 return err;
1696
1697 rtnl_link_failed:
1698 xfrm4_tunnel_deregister(&ipip_handler, AF_INET);
1699 xfrm_tunnel4_failed:
1700 xfrm4_tunnel_deregister(&sit_handler, AF_INET6);
1701 xfrm_tunnel_failed:
1702 unregister_pernet_device(&sit_net_ops);
1703 goto out;
1704 }
1705
1706 module_init(sit_init);
1707 module_exit(sit_cleanup);
1708 MODULE_LICENSE("GPL");
1709 MODULE_ALIAS_NETDEV("sit0");