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[linux/fpc-iii.git] / net / ipv6 / sit.c
blob3dfbcf1dcb1cbdb38a2a0b17a328bb424b139eb0
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 /* Generate icmpv6 with type/code ICMPV6_DEST_UNREACH/ICMPV6_ADDR_UNREACH
482 * if sufficient data bytes are available
483 */
484 static int ipip6_err_gen_icmpv6_unreach(struct sk_buff *skb)
485 {
486 const struct iphdr *iph = (const struct iphdr *) skb->data;
487 struct rt6_info *rt;
488 struct sk_buff *skb2;
489
490 if (!pskb_may_pull(skb, iph->ihl * 4 + sizeof(struct ipv6hdr) + 8))
491 return 1;
492
493 skb2 = skb_clone(skb, GFP_ATOMIC);
494
495 if (!skb2)
496 return 1;
497
498 skb_dst_drop(skb2);
499 skb_pull(skb2, iph->ihl * 4);
500 skb_reset_network_header(skb2);
501
502 rt = rt6_lookup(dev_net(skb->dev), &ipv6_hdr(skb2)->saddr, NULL, 0, 0);
503
504 if (rt && rt->dst.dev)
505 skb2->dev = rt->dst.dev;
506
507 icmpv6_send(skb2, ICMPV6_DEST_UNREACH, ICMPV6_ADDR_UNREACH, 0);
508
509 if (rt)
510 ip6_rt_put(rt);
511
512 kfree_skb(skb2);
513
514 return 0;
515 }
516
517 static int ipip6_err(struct sk_buff *skb, u32 info)
518 {
519 const struct iphdr *iph = (const struct iphdr *)skb->data;
520 const int type = icmp_hdr(skb)->type;
521 const int code = icmp_hdr(skb)->code;
522 struct ip_tunnel *t;
523 int err;
524
525 switch (type) {
526 default:
527 case ICMP_PARAMETERPROB:
528 return 0;
529
530 case ICMP_DEST_UNREACH:
531 switch (code) {
532 case ICMP_SR_FAILED:
533 /* Impossible event. */
534 return 0;
535 default:
536 /* All others are translated to HOST_UNREACH.
537 rfc2003 contains "deep thoughts" about NET_UNREACH,
538 I believe they are just ether pollution. --ANK
539 */
540 break;
541 }
542 break;
543 case ICMP_TIME_EXCEEDED:
544 if (code != ICMP_EXC_TTL)
545 return 0;
546 break;
547 case ICMP_REDIRECT:
548 break;
549 }
550
551 err = -ENOENT;
552
553 t = ipip6_tunnel_lookup(dev_net(skb->dev),
554 skb->dev,
555 iph->daddr,
556 iph->saddr);
557 if (t == NULL)
558 goto out;
559
560 if (type == ICMP_DEST_UNREACH && code == ICMP_FRAG_NEEDED) {
561 ipv4_update_pmtu(skb, dev_net(skb->dev), info,
562 t->dev->ifindex, 0, IPPROTO_IPV6, 0);
563 err = 0;
564 goto out;
565 }
566 if (type == ICMP_REDIRECT) {
567 ipv4_redirect(skb, dev_net(skb->dev), t->dev->ifindex, 0,
568 IPPROTO_IPV6, 0);
569 err = 0;
570 goto out;
571 }
572
573 if (t->parms.iph.daddr == 0)
574 goto out;
575
576 err = 0;
577 if (!ipip6_err_gen_icmpv6_unreach(skb))
578 goto out;
579
580 if (t->parms.iph.ttl == 0 && type == ICMP_TIME_EXCEEDED)
581 goto out;
582
583 if (time_before(jiffies, t->err_time + IPTUNNEL_ERR_TIMEO))
584 t->err_count++;
585 else
586 t->err_count = 1;
587 t->err_time = jiffies;
588 out:
589 return err;
590 }
591
592 static inline bool is_spoofed_6rd(struct ip_tunnel *tunnel, const __be32 v4addr,
593 const struct in6_addr *v6addr)
594 {
595 __be32 v4embed = 0;
596 if (check_6rd(tunnel, v6addr, &v4embed) && v4addr != v4embed)
597 return true;
598 return false;
599 }
600
601 /* Checks if an address matches an address on the tunnel interface.
602 * Used to detect the NAT of proto 41 packets and let them pass spoofing test.
603 * Long story:
604 * This function is called after we considered the packet as spoofed
605 * in is_spoofed_6rd.
606 * We may have a router that is doing NAT for proto 41 packets
607 * for an internal station. Destination a.a.a.a/PREFIX:bbbb:bbbb
608 * will be translated to n.n.n.n/PREFIX:bbbb:bbbb. And is_spoofed_6rd
609 * function will return true, dropping the packet.
610 * But, we can still check if is spoofed against the IP
611 * addresses associated with the interface.
612 */
613 static bool only_dnatted(const struct ip_tunnel *tunnel,
614 const struct in6_addr *v6dst)
615 {
616 int prefix_len;
617
618 #ifdef CONFIG_IPV6_SIT_6RD
619 prefix_len = tunnel->ip6rd.prefixlen + 32
620 - tunnel->ip6rd.relay_prefixlen;
621 #else
622 prefix_len = 48;
623 #endif
624 return ipv6_chk_custom_prefix(v6dst, prefix_len, tunnel->dev);
625 }
626
627 /* Returns true if a packet is spoofed */
628 static bool packet_is_spoofed(struct sk_buff *skb,
629 const struct iphdr *iph,
630 struct ip_tunnel *tunnel)
631 {
632 const struct ipv6hdr *ipv6h;
633
634 if (tunnel->dev->priv_flags & IFF_ISATAP) {
635 if (!isatap_chksrc(skb, iph, tunnel))
636 return true;
637
638 return false;
639 }
640
641 if (tunnel->dev->flags & IFF_POINTOPOINT)
642 return false;
643
644 ipv6h = ipv6_hdr(skb);
645
646 if (unlikely(is_spoofed_6rd(tunnel, iph->saddr, &ipv6h->saddr))) {
647 net_warn_ratelimited("Src spoofed %pI4/%pI6c -> %pI4/%pI6c\n",
648 &iph->saddr, &ipv6h->saddr,
649 &iph->daddr, &ipv6h->daddr);
650 return true;
651 }
652
653 if (likely(!is_spoofed_6rd(tunnel, iph->daddr, &ipv6h->daddr)))
654 return false;
655
656 if (only_dnatted(tunnel, &ipv6h->daddr))
657 return false;
658
659 net_warn_ratelimited("Dst spoofed %pI4/%pI6c -> %pI4/%pI6c\n",
660 &iph->saddr, &ipv6h->saddr,
661 &iph->daddr, &ipv6h->daddr);
662 return true;
663 }
664
665 static int ipip6_rcv(struct sk_buff *skb)
666 {
667 const struct iphdr *iph = ip_hdr(skb);
668 struct ip_tunnel *tunnel;
669 int err;
670
671 tunnel = ipip6_tunnel_lookup(dev_net(skb->dev), skb->dev,
672 iph->saddr, iph->daddr);
673 if (tunnel != NULL) {
674 struct pcpu_sw_netstats *tstats;
675
676 if (tunnel->parms.iph.protocol != IPPROTO_IPV6 &&
677 tunnel->parms.iph.protocol != 0)
678 goto out;
679
680 skb->mac_header = skb->network_header;
681 skb_reset_network_header(skb);
682 IPCB(skb)->flags = 0;
683 skb->protocol = htons(ETH_P_IPV6);
684
685 if (packet_is_spoofed(skb, iph, tunnel)) {
686 tunnel->dev->stats.rx_errors++;
687 goto out;
688 }
689
690 __skb_tunnel_rx(skb, tunnel->dev, tunnel->net);
691
692 err = IP_ECN_decapsulate(iph, skb);
693 if (unlikely(err)) {
694 if (log_ecn_error)
695 net_info_ratelimited("non-ECT from %pI4 with TOS=%#x\n",
696 &iph->saddr, iph->tos);
697 if (err > 1) {
698 ++tunnel->dev->stats.rx_frame_errors;
699 ++tunnel->dev->stats.rx_errors;
700 goto out;
701 }
702 }
703
704 tstats = this_cpu_ptr(tunnel->dev->tstats);
705 u64_stats_update_begin(&tstats->syncp);
706 tstats->rx_packets++;
707 tstats->rx_bytes += skb->len;
708 u64_stats_update_end(&tstats->syncp);
709
710 netif_rx(skb);
711
712 return 0;
713 }
714
715 /* no tunnel matched, let upstream know, ipsec may handle it */
716 return 1;
717 out:
718 kfree_skb(skb);
719 return 0;
720 }
721
722 static const struct tnl_ptk_info tpi = {
723 /* no tunnel info required for ipip. */
724 .proto = htons(ETH_P_IP),
725 };
726
727 static int ipip_rcv(struct sk_buff *skb)
728 {
729 const struct iphdr *iph;
730 struct ip_tunnel *tunnel;
731
732 iph = ip_hdr(skb);
733 tunnel = ipip6_tunnel_lookup(dev_net(skb->dev), skb->dev,
734 iph->saddr, iph->daddr);
735 if (tunnel != NULL) {
736 if (tunnel->parms.iph.protocol != IPPROTO_IPIP &&
737 tunnel->parms.iph.protocol != 0)
738 goto drop;
739
740 if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb))
741 goto drop;
742 if (iptunnel_pull_header(skb, 0, tpi.proto))
743 goto drop;
744 return ip_tunnel_rcv(tunnel, skb, &tpi, log_ecn_error);
745 }
746
747 return 1;
748
749 drop:
750 kfree_skb(skb);
751 return 0;
752 }
753
754 /*
755 * If the IPv6 address comes from 6rd / 6to4 (RFC 3056) addr space this function
756 * stores the embedded IPv4 address in v4dst and returns true.
757 */
758 static bool check_6rd(struct ip_tunnel *tunnel, const struct in6_addr *v6dst,
759 __be32 *v4dst)
760 {
761 #ifdef CONFIG_IPV6_SIT_6RD
762 if (ipv6_prefix_equal(v6dst, &tunnel->ip6rd.prefix,
763 tunnel->ip6rd.prefixlen)) {
764 unsigned int pbw0, pbi0;
765 int pbi1;
766 u32 d;
767
768 pbw0 = tunnel->ip6rd.prefixlen >> 5;
769 pbi0 = tunnel->ip6rd.prefixlen & 0x1f;
770
771 d = (ntohl(v6dst->s6_addr32[pbw0]) << pbi0) >>
772 tunnel->ip6rd.relay_prefixlen;
773
774 pbi1 = pbi0 - tunnel->ip6rd.relay_prefixlen;
775 if (pbi1 > 0)
776 d |= ntohl(v6dst->s6_addr32[pbw0 + 1]) >>
777 (32 - pbi1);
778
779 *v4dst = tunnel->ip6rd.relay_prefix | htonl(d);
780 return true;
781 }
782 #else
783 if (v6dst->s6_addr16[0] == htons(0x2002)) {
784 /* 6to4 v6 addr has 16 bits prefix, 32 v4addr, 16 SLA, ... */
785 memcpy(v4dst, &v6dst->s6_addr16[1], 4);
786 return true;
787 }
788 #endif
789 return false;
790 }
791
792 static inline __be32 try_6rd(struct ip_tunnel *tunnel,
793 const struct in6_addr *v6dst)
794 {
795 __be32 dst = 0;
796 check_6rd(tunnel, v6dst, &dst);
797 return dst;
798 }
799
800 /*
801 * This function assumes it is being called from dev_queue_xmit()
802 * and that skb is filled properly by that function.
803 */
804
805 static netdev_tx_t ipip6_tunnel_xmit(struct sk_buff *skb,
806 struct net_device *dev)
807 {
808 struct ip_tunnel *tunnel = netdev_priv(dev);
809 const struct iphdr *tiph = &tunnel->parms.iph;
810 const struct ipv6hdr *iph6 = ipv6_hdr(skb);
811 u8 tos = tunnel->parms.iph.tos;
812 __be16 df = tiph->frag_off;
813 struct rtable *rt; /* Route to the other host */
814 struct net_device *tdev; /* Device to other host */
815 unsigned int max_headroom; /* The extra header space needed */
816 __be32 dst = tiph->daddr;
817 struct flowi4 fl4;
818 int mtu;
819 const struct in6_addr *addr6;
820 int addr_type;
821 u8 ttl;
822 int err;
823
824 if (skb->protocol != htons(ETH_P_IPV6))
825 goto tx_error;
826
827 if (tos == 1)
828 tos = ipv6_get_dsfield(iph6);
829
830 /* ISATAP (RFC4214) - must come before 6to4 */
831 if (dev->priv_flags & IFF_ISATAP) {
832 struct neighbour *neigh = NULL;
833 bool do_tx_error = false;
834
835 if (skb_dst(skb))
836 neigh = dst_neigh_lookup(skb_dst(skb), &iph6->daddr);
837
838 if (neigh == NULL) {
839 net_dbg_ratelimited("nexthop == NULL\n");
840 goto tx_error;
841 }
842
843 addr6 = (const struct in6_addr *)&neigh->primary_key;
844 addr_type = ipv6_addr_type(addr6);
845
846 if ((addr_type & IPV6_ADDR_UNICAST) &&
847 ipv6_addr_is_isatap(addr6))
848 dst = addr6->s6_addr32[3];
849 else
850 do_tx_error = true;
851
852 neigh_release(neigh);
853 if (do_tx_error)
854 goto tx_error;
855 }
856
857 if (!dst)
858 dst = try_6rd(tunnel, &iph6->daddr);
859
860 if (!dst) {
861 struct neighbour *neigh = NULL;
862 bool do_tx_error = false;
863
864 if (skb_dst(skb))
865 neigh = dst_neigh_lookup(skb_dst(skb), &iph6->daddr);
866
867 if (neigh == NULL) {
868 net_dbg_ratelimited("nexthop == NULL\n");
869 goto tx_error;
870 }
871
872 addr6 = (const struct in6_addr *)&neigh->primary_key;
873 addr_type = ipv6_addr_type(addr6);
874
875 if (addr_type == IPV6_ADDR_ANY) {
876 addr6 = &ipv6_hdr(skb)->daddr;
877 addr_type = ipv6_addr_type(addr6);
878 }
879
880 if ((addr_type & IPV6_ADDR_COMPATv4) != 0)
881 dst = addr6->s6_addr32[3];
882 else
883 do_tx_error = true;
884
885 neigh_release(neigh);
886 if (do_tx_error)
887 goto tx_error;
888 }
889
890 rt = ip_route_output_ports(tunnel->net, &fl4, NULL,
891 dst, tiph->saddr,
892 0, 0,
893 IPPROTO_IPV6, RT_TOS(tos),
894 tunnel->parms.link);
895 if (IS_ERR(rt)) {
896 dev->stats.tx_carrier_errors++;
897 goto tx_error_icmp;
898 }
899 if (rt->rt_type != RTN_UNICAST) {
900 ip_rt_put(rt);
901 dev->stats.tx_carrier_errors++;
902 goto tx_error_icmp;
903 }
904 tdev = rt->dst.dev;
905
906 if (tdev == dev) {
907 ip_rt_put(rt);
908 dev->stats.collisions++;
909 goto tx_error;
910 }
911
912 if (df) {
913 mtu = dst_mtu(&rt->dst) - sizeof(struct iphdr);
914
915 if (mtu < 68) {
916 dev->stats.collisions++;
917 ip_rt_put(rt);
918 goto tx_error;
919 }
920
921 if (mtu < IPV6_MIN_MTU) {
922 mtu = IPV6_MIN_MTU;
923 df = 0;
924 }
925
926 if (tunnel->parms.iph.daddr && skb_dst(skb))
927 skb_dst(skb)->ops->update_pmtu(skb_dst(skb), NULL, skb, mtu);
928
929 if (skb->len > mtu && !skb_is_gso(skb)) {
930 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
931 ip_rt_put(rt);
932 goto tx_error;
933 }
934 }
935
936 if (tunnel->err_count > 0) {
937 if (time_before(jiffies,
938 tunnel->err_time + IPTUNNEL_ERR_TIMEO)) {
939 tunnel->err_count--;
940 dst_link_failure(skb);
941 } else
942 tunnel->err_count = 0;
943 }
944
945 /*
946 * Okay, now see if we can stuff it in the buffer as-is.
947 */
948 max_headroom = LL_RESERVED_SPACE(tdev)+sizeof(struct iphdr);
949
950 if (skb_headroom(skb) < max_headroom || skb_shared(skb) ||
951 (skb_cloned(skb) && !skb_clone_writable(skb, 0))) {
952 struct sk_buff *new_skb = skb_realloc_headroom(skb, max_headroom);
953 if (!new_skb) {
954 ip_rt_put(rt);
955 dev->stats.tx_dropped++;
956 kfree_skb(skb);
957 return NETDEV_TX_OK;
958 }
959 if (skb->sk)
960 skb_set_owner_w(new_skb, skb->sk);
961 dev_kfree_skb(skb);
962 skb = new_skb;
963 iph6 = ipv6_hdr(skb);
964 }
965 ttl = tiph->ttl;
966 if (ttl == 0)
967 ttl = iph6->hop_limit;
968 tos = INET_ECN_encapsulate(tos, ipv6_get_dsfield(iph6));
969
970 skb = iptunnel_handle_offloads(skb, false, SKB_GSO_SIT);
971 if (IS_ERR(skb)) {
972 ip_rt_put(rt);
973 goto out;
974 }
975
976 err = iptunnel_xmit(rt, skb, fl4.saddr, fl4.daddr, IPPROTO_IPV6, tos,
977 ttl, df, !net_eq(tunnel->net, dev_net(dev)));
978 iptunnel_xmit_stats(err, &dev->stats, dev->tstats);
979 return NETDEV_TX_OK;
980
981 tx_error_icmp:
982 dst_link_failure(skb);
983 tx_error:
984 kfree_skb(skb);
985 out:
986 dev->stats.tx_errors++;
987 return NETDEV_TX_OK;
988 }
989
990 static netdev_tx_t ipip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev)
991 {
992 struct ip_tunnel *tunnel = netdev_priv(dev);
993 const struct iphdr *tiph = &tunnel->parms.iph;
994
995 skb = iptunnel_handle_offloads(skb, false, SKB_GSO_IPIP);
996 if (IS_ERR(skb))
997 goto out;
998
999 ip_tunnel_xmit(skb, dev, tiph, IPPROTO_IPIP);
1000 return NETDEV_TX_OK;
1001 out:
1002 dev->stats.tx_errors++;
1003 return NETDEV_TX_OK;
1004 }
1005
1006 static netdev_tx_t sit_tunnel_xmit(struct sk_buff *skb,
1007 struct net_device *dev)
1008 {
1009 switch (skb->protocol) {
1010 case htons(ETH_P_IP):
1011 ipip_tunnel_xmit(skb, dev);
1012 break;
1013 case htons(ETH_P_IPV6):
1014 ipip6_tunnel_xmit(skb, dev);
1015 break;
1016 default:
1017 goto tx_err;
1018 }
1019
1020 return NETDEV_TX_OK;
1021
1022 tx_err:
1023 dev->stats.tx_errors++;
1024 kfree_skb(skb);
1025 return NETDEV_TX_OK;
1026
1027 }
1028
1029 static void ipip6_tunnel_bind_dev(struct net_device *dev)
1030 {
1031 struct net_device *tdev = NULL;
1032 struct ip_tunnel *tunnel;
1033 const struct iphdr *iph;
1034 struct flowi4 fl4;
1035
1036 tunnel = netdev_priv(dev);
1037 iph = &tunnel->parms.iph;
1038
1039 if (iph->daddr) {
1040 struct rtable *rt = ip_route_output_ports(tunnel->net, &fl4,
1041 NULL,
1042 iph->daddr, iph->saddr,
1043 0, 0,
1044 IPPROTO_IPV6,
1045 RT_TOS(iph->tos),
1046 tunnel->parms.link);
1047
1048 if (!IS_ERR(rt)) {
1049 tdev = rt->dst.dev;
1050 ip_rt_put(rt);
1051 }
1052 dev->flags |= IFF_POINTOPOINT;
1053 }
1054
1055 if (!tdev && tunnel->parms.link)
1056 tdev = __dev_get_by_index(tunnel->net, tunnel->parms.link);
1057
1058 if (tdev) {
1059 dev->hard_header_len = tdev->hard_header_len + sizeof(struct iphdr);
1060 dev->mtu = tdev->mtu - sizeof(struct iphdr);
1061 if (dev->mtu < IPV6_MIN_MTU)
1062 dev->mtu = IPV6_MIN_MTU;
1063 }
1064 dev->iflink = tunnel->parms.link;
1065 }
1066
1067 static void ipip6_tunnel_update(struct ip_tunnel *t, struct ip_tunnel_parm *p)
1068 {
1069 struct net *net = t->net;
1070 struct sit_net *sitn = net_generic(net, sit_net_id);
1071
1072 ipip6_tunnel_unlink(sitn, t);
1073 synchronize_net();
1074 t->parms.iph.saddr = p->iph.saddr;
1075 t->parms.iph.daddr = p->iph.daddr;
1076 memcpy(t->dev->dev_addr, &p->iph.saddr, 4);
1077 memcpy(t->dev->broadcast, &p->iph.daddr, 4);
1078 ipip6_tunnel_link(sitn, t);
1079 t->parms.iph.ttl = p->iph.ttl;
1080 t->parms.iph.tos = p->iph.tos;
1081 if (t->parms.link != p->link) {
1082 t->parms.link = p->link;
1083 ipip6_tunnel_bind_dev(t->dev);
1084 }
1085 netdev_state_change(t->dev);
1086 }
1087
1088 #ifdef CONFIG_IPV6_SIT_6RD
1089 static int ipip6_tunnel_update_6rd(struct ip_tunnel *t,
1090 struct ip_tunnel_6rd *ip6rd)
1091 {
1092 struct in6_addr prefix;
1093 __be32 relay_prefix;
1094
1095 if (ip6rd->relay_prefixlen > 32 ||
1096 ip6rd->prefixlen + (32 - ip6rd->relay_prefixlen) > 64)
1097 return -EINVAL;
1098
1099 ipv6_addr_prefix(&prefix, &ip6rd->prefix, ip6rd->prefixlen);
1100 if (!ipv6_addr_equal(&prefix, &ip6rd->prefix))
1101 return -EINVAL;
1102 if (ip6rd->relay_prefixlen)
1103 relay_prefix = ip6rd->relay_prefix &
1104 htonl(0xffffffffUL <<
1105 (32 - ip6rd->relay_prefixlen));
1106 else
1107 relay_prefix = 0;
1108 if (relay_prefix != ip6rd->relay_prefix)
1109 return -EINVAL;
1110
1111 t->ip6rd.prefix = prefix;
1112 t->ip6rd.relay_prefix = relay_prefix;
1113 t->ip6rd.prefixlen = ip6rd->prefixlen;
1114 t->ip6rd.relay_prefixlen = ip6rd->relay_prefixlen;
1115 netdev_state_change(t->dev);
1116 return 0;
1117 }
1118 #endif
1119
1120 static int
1121 ipip6_tunnel_ioctl (struct net_device *dev, struct ifreq *ifr, int cmd)
1122 {
1123 int err = 0;
1124 struct ip_tunnel_parm p;
1125 struct ip_tunnel_prl prl;
1126 struct ip_tunnel *t;
1127 struct net *net = dev_net(dev);
1128 struct sit_net *sitn = net_generic(net, sit_net_id);
1129 #ifdef CONFIG_IPV6_SIT_6RD
1130 struct ip_tunnel_6rd ip6rd;
1131 #endif
1132
1133 switch (cmd) {
1134 case SIOCGETTUNNEL:
1135 #ifdef CONFIG_IPV6_SIT_6RD
1136 case SIOCGET6RD:
1137 #endif
1138 t = NULL;
1139 if (dev == sitn->fb_tunnel_dev) {
1140 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) {
1141 err = -EFAULT;
1142 break;
1143 }
1144 t = ipip6_tunnel_locate(net, &p, 0);
1145 }
1146 if (t == NULL)
1147 t = netdev_priv(dev);
1148
1149 err = -EFAULT;
1150 if (cmd == SIOCGETTUNNEL) {
1151 memcpy(&p, &t->parms, sizeof(p));
1152 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p,
1153 sizeof(p)))
1154 goto done;
1155 #ifdef CONFIG_IPV6_SIT_6RD
1156 } else {
1157 ip6rd.prefix = t->ip6rd.prefix;
1158 ip6rd.relay_prefix = t->ip6rd.relay_prefix;
1159 ip6rd.prefixlen = t->ip6rd.prefixlen;
1160 ip6rd.relay_prefixlen = t->ip6rd.relay_prefixlen;
1161 if (copy_to_user(ifr->ifr_ifru.ifru_data, &ip6rd,
1162 sizeof(ip6rd)))
1163 goto done;
1164 #endif
1165 }
1166 err = 0;
1167 break;
1168
1169 case SIOCADDTUNNEL:
1170 case SIOCCHGTUNNEL:
1171 err = -EPERM;
1172 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1173 goto done;
1174
1175 err = -EFAULT;
1176 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
1177 goto done;
1178
1179 err = -EINVAL;
1180 if (p.iph.protocol != IPPROTO_IPV6 &&
1181 p.iph.protocol != IPPROTO_IPIP &&
1182 p.iph.protocol != 0)
1183 goto done;
1184 if (p.iph.version != 4 ||
1185 p.iph.ihl != 5 || (p.iph.frag_off&htons(~IP_DF)))
1186 goto done;
1187 if (p.iph.ttl)
1188 p.iph.frag_off |= htons(IP_DF);
1189
1190 t = ipip6_tunnel_locate(net, &p, cmd == SIOCADDTUNNEL);
1191
1192 if (dev != sitn->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) {
1193 if (t != NULL) {
1194 if (t->dev != dev) {
1195 err = -EEXIST;
1196 break;
1197 }
1198 } else {
1199 if (((dev->flags&IFF_POINTOPOINT) && !p.iph.daddr) ||
1200 (!(dev->flags&IFF_POINTOPOINT) && p.iph.daddr)) {
1201 err = -EINVAL;
1202 break;
1203 }
1204 t = netdev_priv(dev);
1205 }
1206
1207 ipip6_tunnel_update(t, &p);
1208 }
1209
1210 if (t) {
1211 err = 0;
1212 if (copy_to_user(ifr->ifr_ifru.ifru_data, &t->parms, sizeof(p)))
1213 err = -EFAULT;
1214 } else
1215 err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
1216 break;
1217
1218 case SIOCDELTUNNEL:
1219 err = -EPERM;
1220 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1221 goto done;
1222
1223 if (dev == sitn->fb_tunnel_dev) {
1224 err = -EFAULT;
1225 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
1226 goto done;
1227 err = -ENOENT;
1228 if ((t = ipip6_tunnel_locate(net, &p, 0)) == NULL)
1229 goto done;
1230 err = -EPERM;
1231 if (t == netdev_priv(sitn->fb_tunnel_dev))
1232 goto done;
1233 dev = t->dev;
1234 }
1235 unregister_netdevice(dev);
1236 err = 0;
1237 break;
1238
1239 case SIOCGETPRL:
1240 err = -EINVAL;
1241 if (dev == sitn->fb_tunnel_dev)
1242 goto done;
1243 err = -ENOENT;
1244 if (!(t = netdev_priv(dev)))
1245 goto done;
1246 err = ipip6_tunnel_get_prl(t, ifr->ifr_ifru.ifru_data);
1247 break;
1248
1249 case SIOCADDPRL:
1250 case SIOCDELPRL:
1251 case SIOCCHGPRL:
1252 err = -EPERM;
1253 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1254 goto done;
1255 err = -EINVAL;
1256 if (dev == sitn->fb_tunnel_dev)
1257 goto done;
1258 err = -EFAULT;
1259 if (copy_from_user(&prl, ifr->ifr_ifru.ifru_data, sizeof(prl)))
1260 goto done;
1261 err = -ENOENT;
1262 if (!(t = netdev_priv(dev)))
1263 goto done;
1264
1265 switch (cmd) {
1266 case SIOCDELPRL:
1267 err = ipip6_tunnel_del_prl(t, &prl);
1268 break;
1269 case SIOCADDPRL:
1270 case SIOCCHGPRL:
1271 err = ipip6_tunnel_add_prl(t, &prl, cmd == SIOCCHGPRL);
1272 break;
1273 }
1274 netdev_state_change(dev);
1275 break;
1276
1277 #ifdef CONFIG_IPV6_SIT_6RD
1278 case SIOCADD6RD:
1279 case SIOCCHG6RD:
1280 case SIOCDEL6RD:
1281 err = -EPERM;
1282 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1283 goto done;
1284
1285 err = -EFAULT;
1286 if (copy_from_user(&ip6rd, ifr->ifr_ifru.ifru_data,
1287 sizeof(ip6rd)))
1288 goto done;
1289
1290 t = netdev_priv(dev);
1291
1292 if (cmd != SIOCDEL6RD) {
1293 err = ipip6_tunnel_update_6rd(t, &ip6rd);
1294 if (err < 0)
1295 goto done;
1296 } else
1297 ipip6_tunnel_clone_6rd(dev, sitn);
1298
1299 err = 0;
1300 break;
1301 #endif
1302
1303 default:
1304 err = -EINVAL;
1305 }
1306
1307 done:
1308 return err;
1309 }
1310
1311 static int ipip6_tunnel_change_mtu(struct net_device *dev, int new_mtu)
1312 {
1313 if (new_mtu < IPV6_MIN_MTU || new_mtu > 0xFFF8 - sizeof(struct iphdr))
1314 return -EINVAL;
1315 dev->mtu = new_mtu;
1316 return 0;
1317 }
1318
1319 static const struct net_device_ops ipip6_netdev_ops = {
1320 .ndo_uninit = ipip6_tunnel_uninit,
1321 .ndo_start_xmit = sit_tunnel_xmit,
1322 .ndo_do_ioctl = ipip6_tunnel_ioctl,
1323 .ndo_change_mtu = ipip6_tunnel_change_mtu,
1324 .ndo_get_stats64 = ip_tunnel_get_stats64,
1325 };
1326
1327 static void ipip6_dev_free(struct net_device *dev)
1328 {
1329 free_percpu(dev->tstats);
1330 free_netdev(dev);
1331 }
1332
1333 #define SIT_FEATURES (NETIF_F_SG | \
1334 NETIF_F_FRAGLIST | \
1335 NETIF_F_HIGHDMA | \
1336 NETIF_F_GSO_SOFTWARE | \
1337 NETIF_F_HW_CSUM)
1338
1339 static void ipip6_tunnel_setup(struct net_device *dev)
1340 {
1341 dev->netdev_ops = &ipip6_netdev_ops;
1342 dev->destructor = ipip6_dev_free;
1343
1344 dev->type = ARPHRD_SIT;
1345 dev->hard_header_len = LL_MAX_HEADER + sizeof(struct iphdr);
1346 dev->mtu = ETH_DATA_LEN - sizeof(struct iphdr);
1347 dev->flags = IFF_NOARP;
1348 dev->priv_flags &= ~IFF_XMIT_DST_RELEASE;
1349 dev->iflink = 0;
1350 dev->addr_len = 4;
1351 dev->features |= NETIF_F_LLTX;
1352 dev->features |= SIT_FEATURES;
1353 dev->hw_features |= SIT_FEATURES;
1354 }
1355
1356 static int ipip6_tunnel_init(struct net_device *dev)
1357 {
1358 struct ip_tunnel *tunnel = netdev_priv(dev);
1359 int i;
1360
1361 tunnel->dev = dev;
1362 tunnel->net = dev_net(dev);
1363
1364 memcpy(dev->dev_addr, &tunnel->parms.iph.saddr, 4);
1365 memcpy(dev->broadcast, &tunnel->parms.iph.daddr, 4);
1366
1367 ipip6_tunnel_bind_dev(dev);
1368 dev->tstats = alloc_percpu(struct pcpu_sw_netstats);
1369 if (!dev->tstats)
1370 return -ENOMEM;
1371
1372 for_each_possible_cpu(i) {
1373 struct pcpu_sw_netstats *ipip6_tunnel_stats;
1374 ipip6_tunnel_stats = per_cpu_ptr(dev->tstats, i);
1375 u64_stats_init(&ipip6_tunnel_stats->syncp);
1376 }
1377
1378 return 0;
1379 }
1380
1381 static int __net_init ipip6_fb_tunnel_init(struct net_device *dev)
1382 {
1383 struct ip_tunnel *tunnel = netdev_priv(dev);
1384 struct iphdr *iph = &tunnel->parms.iph;
1385 struct net *net = dev_net(dev);
1386 struct sit_net *sitn = net_generic(net, sit_net_id);
1387 int i;
1388
1389 tunnel->dev = dev;
1390 tunnel->net = dev_net(dev);
1391 strcpy(tunnel->parms.name, dev->name);
1392
1393 iph->version = 4;
1394 iph->protocol = IPPROTO_IPV6;
1395 iph->ihl = 5;
1396 iph->ttl = 64;
1397
1398 dev->tstats = alloc_percpu(struct pcpu_sw_netstats);
1399 if (!dev->tstats)
1400 return -ENOMEM;
1401
1402 for_each_possible_cpu(i) {
1403 struct pcpu_sw_netstats *ipip6_fb_stats;
1404 ipip6_fb_stats = per_cpu_ptr(dev->tstats, i);
1405 u64_stats_init(&ipip6_fb_stats->syncp);
1406 }
1407
1408 dev_hold(dev);
1409 rcu_assign_pointer(sitn->tunnels_wc[0], tunnel);
1410 return 0;
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 #ifdef CONFIG_IPV6_SIT_6RD
1472 /* This function returns true when 6RD attributes are present in the nl msg */
1473 static bool ipip6_netlink_6rd_parms(struct nlattr *data[],
1474 struct ip_tunnel_6rd *ip6rd)
1475 {
1476 bool ret = false;
1477 memset(ip6rd, 0, sizeof(*ip6rd));
1478
1479 if (!data)
1480 return ret;
1481
1482 if (data[IFLA_IPTUN_6RD_PREFIX]) {
1483 ret = true;
1484 nla_memcpy(&ip6rd->prefix, data[IFLA_IPTUN_6RD_PREFIX],
1485 sizeof(struct in6_addr));
1486 }
1487
1488 if (data[IFLA_IPTUN_6RD_RELAY_PREFIX]) {
1489 ret = true;
1490 ip6rd->relay_prefix =
1491 nla_get_be32(data[IFLA_IPTUN_6RD_RELAY_PREFIX]);
1492 }
1493
1494 if (data[IFLA_IPTUN_6RD_PREFIXLEN]) {
1495 ret = true;
1496 ip6rd->prefixlen = nla_get_u16(data[IFLA_IPTUN_6RD_PREFIXLEN]);
1497 }
1498
1499 if (data[IFLA_IPTUN_6RD_RELAY_PREFIXLEN]) {
1500 ret = true;
1501 ip6rd->relay_prefixlen =
1502 nla_get_u16(data[IFLA_IPTUN_6RD_RELAY_PREFIXLEN]);
1503 }
1504
1505 return ret;
1506 }
1507 #endif
1508
1509 static int ipip6_newlink(struct net *src_net, struct net_device *dev,
1510 struct nlattr *tb[], struct nlattr *data[])
1511 {
1512 struct net *net = dev_net(dev);
1513 struct ip_tunnel *nt;
1514 #ifdef CONFIG_IPV6_SIT_6RD
1515 struct ip_tunnel_6rd ip6rd;
1516 #endif
1517 int err;
1518
1519 nt = netdev_priv(dev);
1520 ipip6_netlink_parms(data, &nt->parms);
1521
1522 if (ipip6_tunnel_locate(net, &nt->parms, 0))
1523 return -EEXIST;
1524
1525 err = ipip6_tunnel_create(dev);
1526 if (err < 0)
1527 return err;
1528
1529 #ifdef CONFIG_IPV6_SIT_6RD
1530 if (ipip6_netlink_6rd_parms(data, &ip6rd))
1531 err = ipip6_tunnel_update_6rd(nt, &ip6rd);
1532 #endif
1533
1534 return err;
1535 }
1536
1537 static int ipip6_changelink(struct net_device *dev, struct nlattr *tb[],
1538 struct nlattr *data[])
1539 {
1540 struct ip_tunnel *t = netdev_priv(dev);
1541 struct ip_tunnel_parm p;
1542 struct net *net = t->net;
1543 struct sit_net *sitn = net_generic(net, sit_net_id);
1544 #ifdef CONFIG_IPV6_SIT_6RD
1545 struct ip_tunnel_6rd ip6rd;
1546 #endif
1547
1548 if (dev == sitn->fb_tunnel_dev)
1549 return -EINVAL;
1550
1551 ipip6_netlink_parms(data, &p);
1552
1553 if (((dev->flags & IFF_POINTOPOINT) && !p.iph.daddr) ||
1554 (!(dev->flags & IFF_POINTOPOINT) && p.iph.daddr))
1555 return -EINVAL;
1556
1557 t = ipip6_tunnel_locate(net, &p, 0);
1558
1559 if (t) {
1560 if (t->dev != dev)
1561 return -EEXIST;
1562 } else
1563 t = netdev_priv(dev);
1564
1565 ipip6_tunnel_update(t, &p);
1566
1567 #ifdef CONFIG_IPV6_SIT_6RD
1568 if (ipip6_netlink_6rd_parms(data, &ip6rd))
1569 return ipip6_tunnel_update_6rd(t, &ip6rd);
1570 #endif
1571
1572 return 0;
1573 }
1574
1575 static size_t ipip6_get_size(const struct net_device *dev)
1576 {
1577 return
1578 /* IFLA_IPTUN_LINK */
1579 nla_total_size(4) +
1580 /* IFLA_IPTUN_LOCAL */
1581 nla_total_size(4) +
1582 /* IFLA_IPTUN_REMOTE */
1583 nla_total_size(4) +
1584 /* IFLA_IPTUN_TTL */
1585 nla_total_size(1) +
1586 /* IFLA_IPTUN_TOS */
1587 nla_total_size(1) +
1588 /* IFLA_IPTUN_PMTUDISC */
1589 nla_total_size(1) +
1590 /* IFLA_IPTUN_FLAGS */
1591 nla_total_size(2) +
1592 /* IFLA_IPTUN_PROTO */
1593 nla_total_size(1) +
1594 #ifdef CONFIG_IPV6_SIT_6RD
1595 /* IFLA_IPTUN_6RD_PREFIX */
1596 nla_total_size(sizeof(struct in6_addr)) +
1597 /* IFLA_IPTUN_6RD_RELAY_PREFIX */
1598 nla_total_size(4) +
1599 /* IFLA_IPTUN_6RD_PREFIXLEN */
1600 nla_total_size(2) +
1601 /* IFLA_IPTUN_6RD_RELAY_PREFIXLEN */
1602 nla_total_size(2) +
1603 #endif
1604 0;
1605 }
1606
1607 static int ipip6_fill_info(struct sk_buff *skb, const struct net_device *dev)
1608 {
1609 struct ip_tunnel *tunnel = netdev_priv(dev);
1610 struct ip_tunnel_parm *parm = &tunnel->parms;
1611
1612 if (nla_put_u32(skb, IFLA_IPTUN_LINK, parm->link) ||
1613 nla_put_be32(skb, IFLA_IPTUN_LOCAL, parm->iph.saddr) ||
1614 nla_put_be32(skb, IFLA_IPTUN_REMOTE, parm->iph.daddr) ||
1615 nla_put_u8(skb, IFLA_IPTUN_TTL, parm->iph.ttl) ||
1616 nla_put_u8(skb, IFLA_IPTUN_TOS, parm->iph.tos) ||
1617 nla_put_u8(skb, IFLA_IPTUN_PMTUDISC,
1618 !!(parm->iph.frag_off & htons(IP_DF))) ||
1619 nla_put_u8(skb, IFLA_IPTUN_PROTO, parm->iph.protocol) ||
1620 nla_put_be16(skb, IFLA_IPTUN_FLAGS, parm->i_flags))
1621 goto nla_put_failure;
1622
1623 #ifdef CONFIG_IPV6_SIT_6RD
1624 if (nla_put(skb, IFLA_IPTUN_6RD_PREFIX, sizeof(struct in6_addr),
1625 &tunnel->ip6rd.prefix) ||
1626 nla_put_be32(skb, IFLA_IPTUN_6RD_RELAY_PREFIX,
1627 tunnel->ip6rd.relay_prefix) ||
1628 nla_put_u16(skb, IFLA_IPTUN_6RD_PREFIXLEN,
1629 tunnel->ip6rd.prefixlen) ||
1630 nla_put_u16(skb, IFLA_IPTUN_6RD_RELAY_PREFIXLEN,
1631 tunnel->ip6rd.relay_prefixlen))
1632 goto nla_put_failure;
1633 #endif
1634
1635 return 0;
1636
1637 nla_put_failure:
1638 return -EMSGSIZE;
1639 }
1640
1641 static const struct nla_policy ipip6_policy[IFLA_IPTUN_MAX + 1] = {
1642 [IFLA_IPTUN_LINK] = { .type = NLA_U32 },
1643 [IFLA_IPTUN_LOCAL] = { .type = NLA_U32 },
1644 [IFLA_IPTUN_REMOTE] = { .type = NLA_U32 },
1645 [IFLA_IPTUN_TTL] = { .type = NLA_U8 },
1646 [IFLA_IPTUN_TOS] = { .type = NLA_U8 },
1647 [IFLA_IPTUN_PMTUDISC] = { .type = NLA_U8 },
1648 [IFLA_IPTUN_FLAGS] = { .type = NLA_U16 },
1649 [IFLA_IPTUN_PROTO] = { .type = NLA_U8 },
1650 #ifdef CONFIG_IPV6_SIT_6RD
1651 [IFLA_IPTUN_6RD_PREFIX] = { .len = sizeof(struct in6_addr) },
1652 [IFLA_IPTUN_6RD_RELAY_PREFIX] = { .type = NLA_U32 },
1653 [IFLA_IPTUN_6RD_PREFIXLEN] = { .type = NLA_U16 },
1654 [IFLA_IPTUN_6RD_RELAY_PREFIXLEN] = { .type = NLA_U16 },
1655 #endif
1656 };
1657
1658 static void ipip6_dellink(struct net_device *dev, struct list_head *head)
1659 {
1660 struct net *net = dev_net(dev);
1661 struct sit_net *sitn = net_generic(net, sit_net_id);
1662
1663 if (dev != sitn->fb_tunnel_dev)
1664 unregister_netdevice_queue(dev, head);
1665 }
1666
1667 static struct rtnl_link_ops sit_link_ops __read_mostly = {
1668 .kind = "sit",
1669 .maxtype = IFLA_IPTUN_MAX,
1670 .policy = ipip6_policy,
1671 .priv_size = sizeof(struct ip_tunnel),
1672 .setup = ipip6_tunnel_setup,
1673 .validate = ipip6_validate,
1674 .newlink = ipip6_newlink,
1675 .changelink = ipip6_changelink,
1676 .get_size = ipip6_get_size,
1677 .fill_info = ipip6_fill_info,
1678 .dellink = ipip6_dellink,
1679 };
1680
1681 static struct xfrm_tunnel sit_handler __read_mostly = {
1682 .handler = ipip6_rcv,
1683 .err_handler = ipip6_err,
1684 .priority = 1,
1685 };
1686
1687 static struct xfrm_tunnel ipip_handler __read_mostly = {
1688 .handler = ipip_rcv,
1689 .err_handler = ipip6_err,
1690 .priority = 2,
1691 };
1692
1693 static void __net_exit sit_destroy_tunnels(struct net *net,
1694 struct list_head *head)
1695 {
1696 struct sit_net *sitn = net_generic(net, sit_net_id);
1697 struct net_device *dev, *aux;
1698 int prio;
1699
1700 for_each_netdev_safe(net, dev, aux)
1701 if (dev->rtnl_link_ops == &sit_link_ops)
1702 unregister_netdevice_queue(dev, head);
1703
1704 for (prio = 1; prio < 4; prio++) {
1705 int h;
1706 for (h = 0; h < HASH_SIZE; h++) {
1707 struct ip_tunnel *t;
1708
1709 t = rtnl_dereference(sitn->tunnels[prio][h]);
1710 while (t != NULL) {
1711 /* If dev is in the same netns, it has already
1712 * been added to the list by the previous loop.
1713 */
1714 if (!net_eq(dev_net(t->dev), net))
1715 unregister_netdevice_queue(t->dev,
1716 head);
1717 t = rtnl_dereference(t->next);
1718 }
1719 }
1720 }
1721 }
1722
1723 static int __net_init sit_init_net(struct net *net)
1724 {
1725 struct sit_net *sitn = net_generic(net, sit_net_id);
1726 struct ip_tunnel *t;
1727 int err;
1728
1729 sitn->tunnels[0] = sitn->tunnels_wc;
1730 sitn->tunnels[1] = sitn->tunnels_l;
1731 sitn->tunnels[2] = sitn->tunnels_r;
1732 sitn->tunnels[3] = sitn->tunnels_r_l;
1733
1734 sitn->fb_tunnel_dev = alloc_netdev(sizeof(struct ip_tunnel), "sit0",
1735 ipip6_tunnel_setup);
1736 if (!sitn->fb_tunnel_dev) {
1737 err = -ENOMEM;
1738 goto err_alloc_dev;
1739 }
1740 dev_net_set(sitn->fb_tunnel_dev, net);
1741 sitn->fb_tunnel_dev->rtnl_link_ops = &sit_link_ops;
1742 /* FB netdevice is special: we have one, and only one per netns.
1743 * Allowing to move it to another netns is clearly unsafe.
1744 */
1745 sitn->fb_tunnel_dev->features |= NETIF_F_NETNS_LOCAL;
1746
1747 err = ipip6_fb_tunnel_init(sitn->fb_tunnel_dev);
1748 if (err)
1749 goto err_dev_free;
1750
1751 ipip6_tunnel_clone_6rd(sitn->fb_tunnel_dev, sitn);
1752
1753 if ((err = register_netdev(sitn->fb_tunnel_dev)))
1754 goto err_reg_dev;
1755
1756 t = netdev_priv(sitn->fb_tunnel_dev);
1757
1758 strcpy(t->parms.name, sitn->fb_tunnel_dev->name);
1759 return 0;
1760
1761 err_reg_dev:
1762 dev_put(sitn->fb_tunnel_dev);
1763 err_dev_free:
1764 ipip6_dev_free(sitn->fb_tunnel_dev);
1765 err_alloc_dev:
1766 return err;
1767 }
1768
1769 static void __net_exit sit_exit_net(struct net *net)
1770 {
1771 LIST_HEAD(list);
1772
1773 rtnl_lock();
1774 sit_destroy_tunnels(net, &list);
1775 unregister_netdevice_many(&list);
1776 rtnl_unlock();
1777 }
1778
1779 static struct pernet_operations sit_net_ops = {
1780 .init = sit_init_net,
1781 .exit = sit_exit_net,
1782 .id = &sit_net_id,
1783 .size = sizeof(struct sit_net),
1784 };
1785
1786 static void __exit sit_cleanup(void)
1787 {
1788 rtnl_link_unregister(&sit_link_ops);
1789 xfrm4_tunnel_deregister(&sit_handler, AF_INET6);
1790 xfrm4_tunnel_deregister(&ipip_handler, AF_INET);
1791
1792 unregister_pernet_device(&sit_net_ops);
1793 rcu_barrier(); /* Wait for completion of call_rcu()'s */
1794 }
1795
1796 static int __init sit_init(void)
1797 {
1798 int err;
1799
1800 pr_info("IPv6 over IPv4 tunneling driver\n");
1801
1802 err = register_pernet_device(&sit_net_ops);
1803 if (err < 0)
1804 return err;
1805 err = xfrm4_tunnel_register(&sit_handler, AF_INET6);
1806 if (err < 0) {
1807 pr_info("%s: can't register ip6ip4\n", __func__);
1808 goto xfrm_tunnel_failed;
1809 }
1810 err = xfrm4_tunnel_register(&ipip_handler, AF_INET);
1811 if (err < 0) {
1812 pr_info("%s: can't register ip4ip4\n", __func__);
1813 goto xfrm_tunnel4_failed;
1814 }
1815 err = rtnl_link_register(&sit_link_ops);
1816 if (err < 0)
1817 goto rtnl_link_failed;
1818
1819 out:
1820 return err;
1821
1822 rtnl_link_failed:
1823 xfrm4_tunnel_deregister(&ipip_handler, AF_INET);
1824 xfrm_tunnel4_failed:
1825 xfrm4_tunnel_deregister(&sit_handler, AF_INET6);
1826 xfrm_tunnel_failed:
1827 unregister_pernet_device(&sit_net_ops);
1828 goto out;
1829 }
1830
1831 module_init(sit_init);
1832 module_exit(sit_cleanup);
1833 MODULE_LICENSE("GPL");
1834 MODULE_ALIAS_NETDEV("sit0");
Linux with added FPC-III support