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Linux 4.8-rc8
[linux/fpc-iii.git] / net / ipv6 / sit.c
blob182b6a9be29dfba5514bb74c840afb36cbc367b0
1 /*
2 * IPv6 over IPv4 tunnel device - Simple Internet Transition (SIT)
3 * Linux INET6 implementation
4 *
5 * Authors:
6 * Pedro Roque <roque@di.fc.ul.pt>
7 * Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
8 *
9 * This program is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU General Public License
11 * as published by the Free Software Foundation; either version
12 * 2 of the License, or (at your option) any later version.
13 *
14 * Changes:
15 * Roger Venning <r.venning@telstra.com>: 6to4 support
16 * Nate Thompson <nate@thebog.net>: 6to4 support
17 * Fred Templin <fred.l.templin@boeing.com>: isatap support
18 */
19
20 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
21
22 #include <linux/module.h>
23 #include <linux/capability.h>
24 #include <linux/errno.h>
25 #include <linux/types.h>
26 #include <linux/socket.h>
27 #include <linux/sockios.h>
28 #include <linux/net.h>
29 #include <linux/in6.h>
30 #include <linux/netdevice.h>
31 #include <linux/if_arp.h>
32 #include <linux/icmp.h>
33 #include <linux/slab.h>
34 #include <asm/uaccess.h>
35 #include <linux/init.h>
36 #include <linux/netfilter_ipv4.h>
37 #include <linux/if_ether.h>
38
39 #include <net/sock.h>
40 #include <net/snmp.h>
41
42 #include <net/ipv6.h>
43 #include <net/protocol.h>
44 #include <net/transp_v6.h>
45 #include <net/ip6_fib.h>
46 #include <net/ip6_route.h>
47 #include <net/ndisc.h>
48 #include <net/addrconf.h>
49 #include <net/ip.h>
50 #include <net/udp.h>
51 #include <net/icmp.h>
52 #include <net/ip_tunnels.h>
53 #include <net/inet_ecn.h>
54 #include <net/xfrm.h>
55 #include <net/dsfield.h>
56 #include <net/net_namespace.h>
57 #include <net/netns/generic.h>
58
59 /*
60 This version of net/ipv6/sit.c is cloned of net/ipv4/ip_gre.c
61
62 For comments look at net/ipv4/ip_gre.c --ANK
63 */
64
65 #define HASH_SIZE 16
66 #define HASH(addr) (((__force u32)addr^((__force u32)addr>>4))&0xF)
67
68 static bool log_ecn_error = true;
69 module_param(log_ecn_error, bool, 0644);
70 MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN");
71
72 static int ipip6_tunnel_init(struct net_device *dev);
73 static void ipip6_tunnel_setup(struct net_device *dev);
74 static void ipip6_dev_free(struct net_device *dev);
75 static bool check_6rd(struct ip_tunnel *tunnel, const struct in6_addr *v6dst,
76 __be32 *v4dst);
77 static struct rtnl_link_ops sit_link_ops __read_mostly;
78
79 static int sit_net_id __read_mostly;
80 struct sit_net {
81 struct ip_tunnel __rcu *tunnels_r_l[HASH_SIZE];
82 struct ip_tunnel __rcu *tunnels_r[HASH_SIZE];
83 struct ip_tunnel __rcu *tunnels_l[HASH_SIZE];
84 struct ip_tunnel __rcu *tunnels_wc[1];
85 struct ip_tunnel __rcu **tunnels[4];
86
87 struct net_device *fb_tunnel_dev;
88 };
89
90 /*
91 * Must be invoked with rcu_read_lock
92 */
93 static struct ip_tunnel *ipip6_tunnel_lookup(struct net *net,
94 struct net_device *dev, __be32 remote, __be32 local)
95 {
96 unsigned int h0 = HASH(remote);
97 unsigned int h1 = HASH(local);
98 struct ip_tunnel *t;
99 struct sit_net *sitn = net_generic(net, sit_net_id);
100
101 for_each_ip_tunnel_rcu(t, sitn->tunnels_r_l[h0 ^ h1]) {
102 if (local == t->parms.iph.saddr &&
103 remote == t->parms.iph.daddr &&
104 (!dev || !t->parms.link || dev->ifindex == t->parms.link) &&
105 (t->dev->flags & IFF_UP))
106 return t;
107 }
108 for_each_ip_tunnel_rcu(t, sitn->tunnels_r[h0]) {
109 if (remote == t->parms.iph.daddr &&
110 (!dev || !t->parms.link || dev->ifindex == t->parms.link) &&
111 (t->dev->flags & IFF_UP))
112 return t;
113 }
114 for_each_ip_tunnel_rcu(t, sitn->tunnels_l[h1]) {
115 if (local == t->parms.iph.saddr &&
116 (!dev || !t->parms.link || dev->ifindex == t->parms.link) &&
117 (t->dev->flags & IFF_UP))
118 return t;
119 }
120 t = rcu_dereference(sitn->tunnels_wc[0]);
121 if (t && (t->dev->flags & IFF_UP))
122 return t;
123 return NULL;
124 }
125
126 static struct ip_tunnel __rcu **__ipip6_bucket(struct sit_net *sitn,
127 struct ip_tunnel_parm *parms)
128 {
129 __be32 remote = parms->iph.daddr;
130 __be32 local = parms->iph.saddr;
131 unsigned int h = 0;
132 int prio = 0;
133
134 if (remote) {
135 prio |= 2;
136 h ^= HASH(remote);
137 }
138 if (local) {
139 prio |= 1;
140 h ^= HASH(local);
141 }
142 return &sitn->tunnels[prio][h];
143 }
144
145 static inline struct ip_tunnel __rcu **ipip6_bucket(struct sit_net *sitn,
146 struct ip_tunnel *t)
147 {
148 return __ipip6_bucket(sitn, &t->parms);
149 }
150
151 static void ipip6_tunnel_unlink(struct sit_net *sitn, struct ip_tunnel *t)
152 {
153 struct ip_tunnel __rcu **tp;
154 struct ip_tunnel *iter;
155
156 for (tp = ipip6_bucket(sitn, t);
157 (iter = rtnl_dereference(*tp)) != NULL;
158 tp = &iter->next) {
159 if (t == iter) {
160 rcu_assign_pointer(*tp, t->next);
161 break;
162 }
163 }
164 }
165
166 static void ipip6_tunnel_link(struct sit_net *sitn, struct ip_tunnel *t)
167 {
168 struct ip_tunnel __rcu **tp = ipip6_bucket(sitn, t);
169
170 rcu_assign_pointer(t->next, rtnl_dereference(*tp));
171 rcu_assign_pointer(*tp, t);
172 }
173
174 static void ipip6_tunnel_clone_6rd(struct net_device *dev, struct sit_net *sitn)
175 {
176 #ifdef CONFIG_IPV6_SIT_6RD
177 struct ip_tunnel *t = netdev_priv(dev);
178
179 if (t->dev == sitn->fb_tunnel_dev) {
180 ipv6_addr_set(&t->ip6rd.prefix, htonl(0x20020000), 0, 0, 0);
181 t->ip6rd.relay_prefix = 0;
182 t->ip6rd.prefixlen = 16;
183 t->ip6rd.relay_prefixlen = 0;
184 } else {
185 struct ip_tunnel *t0 = netdev_priv(sitn->fb_tunnel_dev);
186 memcpy(&t->ip6rd, &t0->ip6rd, sizeof(t->ip6rd));
187 }
188 #endif
189 }
190
191 static int ipip6_tunnel_create(struct net_device *dev)
192 {
193 struct ip_tunnel *t = netdev_priv(dev);
194 struct net *net = dev_net(dev);
195 struct sit_net *sitn = net_generic(net, sit_net_id);
196 int err;
197
198 memcpy(dev->dev_addr, &t->parms.iph.saddr, 4);
199 memcpy(dev->broadcast, &t->parms.iph.daddr, 4);
200
201 if ((__force u16)t->parms.i_flags & SIT_ISATAP)
202 dev->priv_flags |= IFF_ISATAP;
203
204 dev->rtnl_link_ops = &sit_link_ops;
205
206 err = register_netdevice(dev);
207 if (err < 0)
208 goto out;
209
210 ipip6_tunnel_clone_6rd(dev, sitn);
211
212 dev_hold(dev);
213
214 ipip6_tunnel_link(sitn, t);
215 return 0;
216
217 out:
218 return err;
219 }
220
221 static struct ip_tunnel *ipip6_tunnel_locate(struct net *net,
222 struct ip_tunnel_parm *parms, int create)
223 {
224 __be32 remote = parms->iph.daddr;
225 __be32 local = parms->iph.saddr;
226 struct ip_tunnel *t, *nt;
227 struct ip_tunnel __rcu **tp;
228 struct net_device *dev;
229 char name[IFNAMSIZ];
230 struct sit_net *sitn = net_generic(net, sit_net_id);
231
232 for (tp = __ipip6_bucket(sitn, parms);
233 (t = rtnl_dereference(*tp)) != NULL;
234 tp = &t->next) {
235 if (local == t->parms.iph.saddr &&
236 remote == t->parms.iph.daddr &&
237 parms->link == t->parms.link) {
238 if (create)
239 return NULL;
240 else
241 return t;
242 }
243 }
244 if (!create)
245 goto failed;
246
247 if (parms->name[0])
248 strlcpy(name, parms->name, IFNAMSIZ);
249 else
250 strcpy(name, "sit%d");
251
252 dev = alloc_netdev(sizeof(*t), name, NET_NAME_UNKNOWN,
253 ipip6_tunnel_setup);
254 if (!dev)
255 return NULL;
256
257 dev_net_set(dev, net);
258
259 nt = netdev_priv(dev);
260
261 nt->parms = *parms;
262 if (ipip6_tunnel_create(dev) < 0)
263 goto failed_free;
264
265 return nt;
266
267 failed_free:
268 ipip6_dev_free(dev);
269 failed:
270 return NULL;
271 }
272
273 #define for_each_prl_rcu(start) \
274 for (prl = rcu_dereference(start); \
275 prl; \
276 prl = rcu_dereference(prl->next))
277
278 static struct ip_tunnel_prl_entry *
279 __ipip6_tunnel_locate_prl(struct ip_tunnel *t, __be32 addr)
280 {
281 struct ip_tunnel_prl_entry *prl;
282
283 for_each_prl_rcu(t->prl)
284 if (prl->addr == addr)
285 break;
286 return prl;
287
288 }
289
290 static int ipip6_tunnel_get_prl(struct ip_tunnel *t,
291 struct ip_tunnel_prl __user *a)
292 {
293 struct ip_tunnel_prl kprl, *kp;
294 struct ip_tunnel_prl_entry *prl;
295 unsigned int cmax, c = 0, ca, len;
296 int ret = 0;
297
298 if (copy_from_user(&kprl, a, sizeof(kprl)))
299 return -EFAULT;
300 cmax = kprl.datalen / sizeof(kprl);
301 if (cmax > 1 && kprl.addr != htonl(INADDR_ANY))
302 cmax = 1;
303
304 /* For simple GET or for root users,
305 * we try harder to allocate.
306 */
307 kp = (cmax <= 1 || capable(CAP_NET_ADMIN)) ?
308 kcalloc(cmax, sizeof(*kp), GFP_KERNEL) :
309 NULL;
310
311 rcu_read_lock();
312
313 ca = t->prl_count < cmax ? t->prl_count : cmax;
314
315 if (!kp) {
316 /* We don't try hard to allocate much memory for
317 * non-root users.
318 * For root users, retry allocating enough memory for
319 * the answer.
320 */
321 kp = kcalloc(ca, sizeof(*kp), GFP_ATOMIC);
322 if (!kp) {
323 ret = -ENOMEM;
324 goto out;
325 }
326 }
327
328 c = 0;
329 for_each_prl_rcu(t->prl) {
330 if (c >= cmax)
331 break;
332 if (kprl.addr != htonl(INADDR_ANY) && prl->addr != kprl.addr)
333 continue;
334 kp[c].addr = prl->addr;
335 kp[c].flags = prl->flags;
336 c++;
337 if (kprl.addr != htonl(INADDR_ANY))
338 break;
339 }
340 out:
341 rcu_read_unlock();
342
343 len = sizeof(*kp) * c;
344 ret = 0;
345 if ((len && copy_to_user(a + 1, kp, len)) || put_user(len, &a->datalen))
346 ret = -EFAULT;
347
348 kfree(kp);
349
350 return ret;
351 }
352
353 static int
354 ipip6_tunnel_add_prl(struct ip_tunnel *t, struct ip_tunnel_prl *a, int chg)
355 {
356 struct ip_tunnel_prl_entry *p;
357 int err = 0;
358
359 if (a->addr == htonl(INADDR_ANY))
360 return -EINVAL;
361
362 ASSERT_RTNL();
363
364 for (p = rtnl_dereference(t->prl); p; p = rtnl_dereference(p->next)) {
365 if (p->addr == a->addr) {
366 if (chg) {
367 p->flags = a->flags;
368 goto out;
369 }
370 err = -EEXIST;
371 goto out;
372 }
373 }
374
375 if (chg) {
376 err = -ENXIO;
377 goto out;
378 }
379
380 p = kzalloc(sizeof(struct ip_tunnel_prl_entry), GFP_KERNEL);
381 if (!p) {
382 err = -ENOBUFS;
383 goto out;
384 }
385
386 p->next = t->prl;
387 p->addr = a->addr;
388 p->flags = a->flags;
389 t->prl_count++;
390 rcu_assign_pointer(t->prl, p);
391 out:
392 return err;
393 }
394
395 static void prl_list_destroy_rcu(struct rcu_head *head)
396 {
397 struct ip_tunnel_prl_entry *p, *n;
398
399 p = container_of(head, struct ip_tunnel_prl_entry, rcu_head);
400 do {
401 n = rcu_dereference_protected(p->next, 1);
402 kfree(p);
403 p = n;
404 } while (p);
405 }
406
407 static int
408 ipip6_tunnel_del_prl(struct ip_tunnel *t, struct ip_tunnel_prl *a)
409 {
410 struct ip_tunnel_prl_entry *x;
411 struct ip_tunnel_prl_entry __rcu **p;
412 int err = 0;
413
414 ASSERT_RTNL();
415
416 if (a && a->addr != htonl(INADDR_ANY)) {
417 for (p = &t->prl;
418 (x = rtnl_dereference(*p)) != NULL;
419 p = &x->next) {
420 if (x->addr == a->addr) {
421 *p = x->next;
422 kfree_rcu(x, rcu_head);
423 t->prl_count--;
424 goto out;
425 }
426 }
427 err = -ENXIO;
428 } else {
429 x = rtnl_dereference(t->prl);
430 if (x) {
431 t->prl_count = 0;
432 call_rcu(&x->rcu_head, prl_list_destroy_rcu);
433 t->prl = NULL;
434 }
435 }
436 out:
437 return err;
438 }
439
440 static int
441 isatap_chksrc(struct sk_buff *skb, const struct iphdr *iph, struct ip_tunnel *t)
442 {
443 struct ip_tunnel_prl_entry *p;
444 int ok = 1;
445
446 rcu_read_lock();
447 p = __ipip6_tunnel_locate_prl(t, iph->saddr);
448 if (p) {
449 if (p->flags & PRL_DEFAULT)
450 skb->ndisc_nodetype = NDISC_NODETYPE_DEFAULT;
451 else
452 skb->ndisc_nodetype = NDISC_NODETYPE_NODEFAULT;
453 } else {
454 const struct in6_addr *addr6 = &ipv6_hdr(skb)->saddr;
455
456 if (ipv6_addr_is_isatap(addr6) &&
457 (addr6->s6_addr32[3] == iph->saddr) &&
458 ipv6_chk_prefix(addr6, t->dev))
459 skb->ndisc_nodetype = NDISC_NODETYPE_HOST;
460 else
461 ok = 0;
462 }
463 rcu_read_unlock();
464 return ok;
465 }
466
467 static void ipip6_tunnel_uninit(struct net_device *dev)
468 {
469 struct ip_tunnel *tunnel = netdev_priv(dev);
470 struct sit_net *sitn = net_generic(tunnel->net, sit_net_id);
471
472 if (dev == sitn->fb_tunnel_dev) {
473 RCU_INIT_POINTER(sitn->tunnels_wc[0], NULL);
474 } else {
475 ipip6_tunnel_unlink(sitn, tunnel);
476 ipip6_tunnel_del_prl(tunnel, NULL);
477 }
478 dst_cache_reset(&tunnel->dst_cache);
479 dev_put(dev);
480 }
481
482 static int ipip6_err(struct sk_buff *skb, u32 info)
483 {
484 const struct iphdr *iph = (const struct iphdr *)skb->data;
485 const int type = icmp_hdr(skb)->type;
486 const int code = icmp_hdr(skb)->code;
487 unsigned int data_len = 0;
488 struct ip_tunnel *t;
489 int err;
490
491 switch (type) {
492 default:
493 case ICMP_PARAMETERPROB:
494 return 0;
495
496 case ICMP_DEST_UNREACH:
497 switch (code) {
498 case ICMP_SR_FAILED:
499 /* Impossible event. */
500 return 0;
501 default:
502 /* All others are translated to HOST_UNREACH.
503 rfc2003 contains "deep thoughts" about NET_UNREACH,
504 I believe they are just ether pollution. --ANK
505 */
506 break;
507 }
508 break;
509 case ICMP_TIME_EXCEEDED:
510 if (code != ICMP_EXC_TTL)
511 return 0;
512 data_len = icmp_hdr(skb)->un.reserved[1] * 4; /* RFC 4884 4.1 */
513 break;
514 case ICMP_REDIRECT:
515 break;
516 }
517
518 err = -ENOENT;
519
520 t = ipip6_tunnel_lookup(dev_net(skb->dev),
521 skb->dev,
522 iph->daddr,
523 iph->saddr);
524 if (!t)
525 goto out;
526
527 if (type == ICMP_DEST_UNREACH && code == ICMP_FRAG_NEEDED) {
528 ipv4_update_pmtu(skb, dev_net(skb->dev), info,
529 t->parms.link, 0, iph->protocol, 0);
530 err = 0;
531 goto out;
532 }
533 if (type == ICMP_REDIRECT) {
534 ipv4_redirect(skb, dev_net(skb->dev), t->parms.link, 0,
535 iph->protocol, 0);
536 err = 0;
537 goto out;
538 }
539
540 err = 0;
541 if (!ip6_err_gen_icmpv6_unreach(skb, iph->ihl * 4, type, data_len))
542 goto out;
543
544 if (t->parms.iph.daddr == 0)
545 goto out;
546
547 if (t->parms.iph.ttl == 0 && type == ICMP_TIME_EXCEEDED)
548 goto out;
549
550 if (time_before(jiffies, t->err_time + IPTUNNEL_ERR_TIMEO))
551 t->err_count++;
552 else
553 t->err_count = 1;
554 t->err_time = jiffies;
555 out:
556 return err;
557 }
558
559 static inline bool is_spoofed_6rd(struct ip_tunnel *tunnel, const __be32 v4addr,
560 const struct in6_addr *v6addr)
561 {
562 __be32 v4embed = 0;
563 if (check_6rd(tunnel, v6addr, &v4embed) && v4addr != v4embed)
564 return true;
565 return false;
566 }
567
568 /* Checks if an address matches an address on the tunnel interface.
569 * Used to detect the NAT of proto 41 packets and let them pass spoofing test.
570 * Long story:
571 * This function is called after we considered the packet as spoofed
572 * in is_spoofed_6rd.
573 * We may have a router that is doing NAT for proto 41 packets
574 * for an internal station. Destination a.a.a.a/PREFIX:bbbb:bbbb
575 * will be translated to n.n.n.n/PREFIX:bbbb:bbbb. And is_spoofed_6rd
576 * function will return true, dropping the packet.
577 * But, we can still check if is spoofed against the IP
578 * addresses associated with the interface.
579 */
580 static bool only_dnatted(const struct ip_tunnel *tunnel,
581 const struct in6_addr *v6dst)
582 {
583 int prefix_len;
584
585 #ifdef CONFIG_IPV6_SIT_6RD
586 prefix_len = tunnel->ip6rd.prefixlen + 32
587 - tunnel->ip6rd.relay_prefixlen;
588 #else
589 prefix_len = 48;
590 #endif
591 return ipv6_chk_custom_prefix(v6dst, prefix_len, tunnel->dev);
592 }
593
594 /* Returns true if a packet is spoofed */
595 static bool packet_is_spoofed(struct sk_buff *skb,
596 const struct iphdr *iph,
597 struct ip_tunnel *tunnel)
598 {
599 const struct ipv6hdr *ipv6h;
600
601 if (tunnel->dev->priv_flags & IFF_ISATAP) {
602 if (!isatap_chksrc(skb, iph, tunnel))
603 return true;
604
605 return false;
606 }
607
608 if (tunnel->dev->flags & IFF_POINTOPOINT)
609 return false;
610
611 ipv6h = ipv6_hdr(skb);
612
613 if (unlikely(is_spoofed_6rd(tunnel, iph->saddr, &ipv6h->saddr))) {
614 net_warn_ratelimited("Src spoofed %pI4/%pI6c -> %pI4/%pI6c\n",
615 &iph->saddr, &ipv6h->saddr,
616 &iph->daddr, &ipv6h->daddr);
617 return true;
618 }
619
620 if (likely(!is_spoofed_6rd(tunnel, iph->daddr, &ipv6h->daddr)))
621 return false;
622
623 if (only_dnatted(tunnel, &ipv6h->daddr))
624 return false;
625
626 net_warn_ratelimited("Dst spoofed %pI4/%pI6c -> %pI4/%pI6c\n",
627 &iph->saddr, &ipv6h->saddr,
628 &iph->daddr, &ipv6h->daddr);
629 return true;
630 }
631
632 static int ipip6_rcv(struct sk_buff *skb)
633 {
634 const struct iphdr *iph = ip_hdr(skb);
635 struct ip_tunnel *tunnel;
636 int err;
637
638 tunnel = ipip6_tunnel_lookup(dev_net(skb->dev), skb->dev,
639 iph->saddr, iph->daddr);
640 if (tunnel) {
641 struct pcpu_sw_netstats *tstats;
642
643 if (tunnel->parms.iph.protocol != IPPROTO_IPV6 &&
644 tunnel->parms.iph.protocol != 0)
645 goto out;
646
647 skb->mac_header = skb->network_header;
648 skb_reset_network_header(skb);
649 IPCB(skb)->flags = 0;
650 skb->dev = tunnel->dev;
651
652 if (packet_is_spoofed(skb, iph, tunnel)) {
653 tunnel->dev->stats.rx_errors++;
654 goto out;
655 }
656
657 if (iptunnel_pull_header(skb, 0, htons(ETH_P_IPV6),
658 !net_eq(tunnel->net, dev_net(tunnel->dev))))
659 goto out;
660
661 err = IP_ECN_decapsulate(iph, skb);
662 if (unlikely(err)) {
663 if (log_ecn_error)
664 net_info_ratelimited("non-ECT from %pI4 with TOS=%#x\n",
665 &iph->saddr, iph->tos);
666 if (err > 1) {
667 ++tunnel->dev->stats.rx_frame_errors;
668 ++tunnel->dev->stats.rx_errors;
669 goto out;
670 }
671 }
672
673 tstats = this_cpu_ptr(tunnel->dev->tstats);
674 u64_stats_update_begin(&tstats->syncp);
675 tstats->rx_packets++;
676 tstats->rx_bytes += skb->len;
677 u64_stats_update_end(&tstats->syncp);
678
679 netif_rx(skb);
680
681 return 0;
682 }
683
684 /* no tunnel matched, let upstream know, ipsec may handle it */
685 return 1;
686 out:
687 kfree_skb(skb);
688 return 0;
689 }
690
691 static const struct tnl_ptk_info ipip_tpi = {
692 /* no tunnel info required for ipip. */
693 .proto = htons(ETH_P_IP),
694 };
695
696 #if IS_ENABLED(CONFIG_MPLS)
697 static const struct tnl_ptk_info mplsip_tpi = {
698 /* no tunnel info required for mplsip. */
699 .proto = htons(ETH_P_MPLS_UC),
700 };
701 #endif
702
703 static int sit_tunnel_rcv(struct sk_buff *skb, u8 ipproto)
704 {
705 const struct iphdr *iph;
706 struct ip_tunnel *tunnel;
707
708 iph = ip_hdr(skb);
709 tunnel = ipip6_tunnel_lookup(dev_net(skb->dev), skb->dev,
710 iph->saddr, iph->daddr);
711 if (tunnel) {
712 const struct tnl_ptk_info *tpi;
713
714 if (tunnel->parms.iph.protocol != ipproto &&
715 tunnel->parms.iph.protocol != 0)
716 goto drop;
717
718 if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb))
719 goto drop;
720 #if IS_ENABLED(CONFIG_MPLS)
721 if (ipproto == IPPROTO_MPLS)
722 tpi = &mplsip_tpi;
723 else
724 #endif
725 tpi = &ipip_tpi;
726 if (iptunnel_pull_header(skb, 0, tpi->proto, false))
727 goto drop;
728 return ip_tunnel_rcv(tunnel, skb, tpi, NULL, log_ecn_error);
729 }
730
731 return 1;
732
733 drop:
734 kfree_skb(skb);
735 return 0;
736 }
737
738 static int ipip_rcv(struct sk_buff *skb)
739 {
740 return sit_tunnel_rcv(skb, IPPROTO_IPIP);
741 }
742
743 #if IS_ENABLED(CONFIG_MPLS)
744 static int mplsip_rcv(struct sk_buff *skb)
745 {
746 return sit_tunnel_rcv(skb, IPPROTO_MPLS);
747 }
748 #endif
749
750 /*
751 * If the IPv6 address comes from 6rd / 6to4 (RFC 3056) addr space this function
752 * stores the embedded IPv4 address in v4dst and returns true.
753 */
754 static bool check_6rd(struct ip_tunnel *tunnel, const struct in6_addr *v6dst,
755 __be32 *v4dst)
756 {
757 #ifdef CONFIG_IPV6_SIT_6RD
758 if (ipv6_prefix_equal(v6dst, &tunnel->ip6rd.prefix,
759 tunnel->ip6rd.prefixlen)) {
760 unsigned int pbw0, pbi0;
761 int pbi1;
762 u32 d;
763
764 pbw0 = tunnel->ip6rd.prefixlen >> 5;
765 pbi0 = tunnel->ip6rd.prefixlen & 0x1f;
766
767 d = (ntohl(v6dst->s6_addr32[pbw0]) << pbi0) >>
768 tunnel->ip6rd.relay_prefixlen;
769
770 pbi1 = pbi0 - tunnel->ip6rd.relay_prefixlen;
771 if (pbi1 > 0)
772 d |= ntohl(v6dst->s6_addr32[pbw0 + 1]) >>
773 (32 - pbi1);
774
775 *v4dst = tunnel->ip6rd.relay_prefix | htonl(d);
776 return true;
777 }
778 #else
779 if (v6dst->s6_addr16[0] == htons(0x2002)) {
780 /* 6to4 v6 addr has 16 bits prefix, 32 v4addr, 16 SLA, ... */
781 memcpy(v4dst, &v6dst->s6_addr16[1], 4);
782 return true;
783 }
784 #endif
785 return false;
786 }
787
788 static inline __be32 try_6rd(struct ip_tunnel *tunnel,
789 const struct in6_addr *v6dst)
790 {
791 __be32 dst = 0;
792 check_6rd(tunnel, v6dst, &dst);
793 return dst;
794 }
795
796 /*
797 * This function assumes it is being called from dev_queue_xmit()
798 * and that skb is filled properly by that function.
799 */
800
801 static netdev_tx_t ipip6_tunnel_xmit(struct sk_buff *skb,
802 struct net_device *dev)
803 {
804 struct ip_tunnel *tunnel = netdev_priv(dev);
805 const struct iphdr *tiph = &tunnel->parms.iph;
806 const struct ipv6hdr *iph6 = ipv6_hdr(skb);
807 u8 tos = tunnel->parms.iph.tos;
808 __be16 df = tiph->frag_off;
809 struct rtable *rt; /* Route to the other host */
810 struct net_device *tdev; /* Device to other host */
811 unsigned int max_headroom; /* The extra header space needed */
812 __be32 dst = tiph->daddr;
813 struct flowi4 fl4;
814 int mtu;
815 const struct in6_addr *addr6;
816 int addr_type;
817 u8 ttl;
818 u8 protocol = IPPROTO_IPV6;
819 int t_hlen = tunnel->hlen + sizeof(struct iphdr);
820
821 if (tos == 1)
822 tos = ipv6_get_dsfield(iph6);
823
824 /* ISATAP (RFC4214) - must come before 6to4 */
825 if (dev->priv_flags & IFF_ISATAP) {
826 struct neighbour *neigh = NULL;
827 bool do_tx_error = false;
828
829 if (skb_dst(skb))
830 neigh = dst_neigh_lookup(skb_dst(skb), &iph6->daddr);
831
832 if (!neigh) {
833 net_dbg_ratelimited("nexthop == NULL\n");
834 goto tx_error;
835 }
836
837 addr6 = (const struct in6_addr *)&neigh->primary_key;
838 addr_type = ipv6_addr_type(addr6);
839
840 if ((addr_type & IPV6_ADDR_UNICAST) &&
841 ipv6_addr_is_isatap(addr6))
842 dst = addr6->s6_addr32[3];
843 else
844 do_tx_error = true;
845
846 neigh_release(neigh);
847 if (do_tx_error)
848 goto tx_error;
849 }
850
851 if (!dst)
852 dst = try_6rd(tunnel, &iph6->daddr);
853
854 if (!dst) {
855 struct neighbour *neigh = NULL;
856 bool do_tx_error = false;
857
858 if (skb_dst(skb))
859 neigh = dst_neigh_lookup(skb_dst(skb), &iph6->daddr);
860
861 if (!neigh) {
862 net_dbg_ratelimited("nexthop == NULL\n");
863 goto tx_error;
864 }
865
866 addr6 = (const struct in6_addr *)&neigh->primary_key;
867 addr_type = ipv6_addr_type(addr6);
868
869 if (addr_type == IPV6_ADDR_ANY) {
870 addr6 = &ipv6_hdr(skb)->daddr;
871 addr_type = ipv6_addr_type(addr6);
872 }
873
874 if ((addr_type & IPV6_ADDR_COMPATv4) != 0)
875 dst = addr6->s6_addr32[3];
876 else
877 do_tx_error = true;
878
879 neigh_release(neigh);
880 if (do_tx_error)
881 goto tx_error;
882 }
883
884 rt = ip_route_output_ports(tunnel->net, &fl4, NULL,
885 dst, tiph->saddr,
886 0, 0,
887 IPPROTO_IPV6, RT_TOS(tos),
888 tunnel->parms.link);
889 if (IS_ERR(rt)) {
890 dev->stats.tx_carrier_errors++;
891 goto tx_error_icmp;
892 }
893 if (rt->rt_type != RTN_UNICAST) {
894 ip_rt_put(rt);
895 dev->stats.tx_carrier_errors++;
896 goto tx_error_icmp;
897 }
898 tdev = rt->dst.dev;
899
900 if (tdev == dev) {
901 ip_rt_put(rt);
902 dev->stats.collisions++;
903 goto tx_error;
904 }
905
906 if (iptunnel_handle_offloads(skb, SKB_GSO_IPXIP4)) {
907 ip_rt_put(rt);
908 goto tx_error;
909 }
910
911 if (df) {
912 mtu = dst_mtu(&rt->dst) - t_hlen;
913
914 if (mtu < 68) {
915 dev->stats.collisions++;
916 ip_rt_put(rt);
917 goto tx_error;
918 }
919
920 if (mtu < IPV6_MIN_MTU) {
921 mtu = IPV6_MIN_MTU;
922 df = 0;
923 }
924
925 if (tunnel->parms.iph.daddr && skb_dst(skb))
926 skb_dst(skb)->ops->update_pmtu(skb_dst(skb), NULL, skb, mtu);
927
928 if (skb->len > mtu && !skb_is_gso(skb)) {
929 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
930 ip_rt_put(rt);
931 goto tx_error;
932 }
933 }
934
935 if (tunnel->err_count > 0) {
936 if (time_before(jiffies,
937 tunnel->err_time + IPTUNNEL_ERR_TIMEO)) {
938 tunnel->err_count--;
939 dst_link_failure(skb);
940 } else
941 tunnel->err_count = 0;
942 }
943
944 /*
945 * Okay, now see if we can stuff it in the buffer as-is.
946 */
947 max_headroom = LL_RESERVED_SPACE(tdev) + t_hlen;
948
949 if (skb_headroom(skb) < max_headroom || skb_shared(skb) ||
950 (skb_cloned(skb) && !skb_clone_writable(skb, 0))) {
951 struct sk_buff *new_skb = skb_realloc_headroom(skb, max_headroom);
952 if (!new_skb) {
953 ip_rt_put(rt);
954 dev->stats.tx_dropped++;
955 kfree_skb(skb);
956 return NETDEV_TX_OK;
957 }
958 if (skb->sk)
959 skb_set_owner_w(new_skb, skb->sk);
960 dev_kfree_skb(skb);
961 skb = new_skb;
962 iph6 = ipv6_hdr(skb);
963 }
964 ttl = tiph->ttl;
965 if (ttl == 0)
966 ttl = iph6->hop_limit;
967 tos = INET_ECN_encapsulate(tos, ipv6_get_dsfield(iph6));
968
969 if (ip_tunnel_encap(skb, tunnel, &protocol, &fl4) < 0) {
970 ip_rt_put(rt);
971 goto tx_error;
972 }
973
974 skb_set_inner_ipproto(skb, IPPROTO_IPV6);
975
976 iptunnel_xmit(NULL, rt, skb, fl4.saddr, fl4.daddr, protocol, tos, ttl,
977 df, !net_eq(tunnel->net, dev_net(dev)));
978 return NETDEV_TX_OK;
979
980 tx_error_icmp:
981 dst_link_failure(skb);
982 tx_error:
983 kfree_skb(skb);
984 dev->stats.tx_errors++;
985 return NETDEV_TX_OK;
986 }
987
988 static netdev_tx_t sit_tunnel_xmit__(struct sk_buff *skb,
989 struct net_device *dev, u8 ipproto)
990 {
991 struct ip_tunnel *tunnel = netdev_priv(dev);
992 const struct iphdr *tiph = &tunnel->parms.iph;
993
994 if (iptunnel_handle_offloads(skb, SKB_GSO_IPXIP4))
995 goto tx_error;
996
997 skb_set_inner_ipproto(skb, ipproto);
998
999 ip_tunnel_xmit(skb, dev, tiph, ipproto);
1000 return NETDEV_TX_OK;
1001 tx_error:
1002 kfree_skb(skb);
1003 dev->stats.tx_errors++;
1004 return NETDEV_TX_OK;
1005 }
1006
1007 static netdev_tx_t sit_tunnel_xmit(struct sk_buff *skb,
1008 struct net_device *dev)
1009 {
1010 switch (skb->protocol) {
1011 case htons(ETH_P_IP):
1012 sit_tunnel_xmit__(skb, dev, IPPROTO_IPIP);
1013 break;
1014 case htons(ETH_P_IPV6):
1015 ipip6_tunnel_xmit(skb, dev);
1016 break;
1017 #if IS_ENABLED(CONFIG_MPLS)
1018 case htons(ETH_P_MPLS_UC):
1019 sit_tunnel_xmit__(skb, dev, IPPROTO_MPLS);
1020 break;
1021 #endif
1022 default:
1023 goto tx_err;
1024 }
1025
1026 return NETDEV_TX_OK;
1027
1028 tx_err:
1029 dev->stats.tx_errors++;
1030 kfree_skb(skb);
1031 return NETDEV_TX_OK;
1032
1033 }
1034
1035 static void ipip6_tunnel_bind_dev(struct net_device *dev)
1036 {
1037 struct net_device *tdev = NULL;
1038 struct ip_tunnel *tunnel;
1039 const struct iphdr *iph;
1040 struct flowi4 fl4;
1041
1042 tunnel = netdev_priv(dev);
1043 iph = &tunnel->parms.iph;
1044
1045 if (iph->daddr) {
1046 struct rtable *rt = ip_route_output_ports(tunnel->net, &fl4,
1047 NULL,
1048 iph->daddr, iph->saddr,
1049 0, 0,
1050 IPPROTO_IPV6,
1051 RT_TOS(iph->tos),
1052 tunnel->parms.link);
1053
1054 if (!IS_ERR(rt)) {
1055 tdev = rt->dst.dev;
1056 ip_rt_put(rt);
1057 }
1058 dev->flags |= IFF_POINTOPOINT;
1059 }
1060
1061 if (!tdev && tunnel->parms.link)
1062 tdev = __dev_get_by_index(tunnel->net, tunnel->parms.link);
1063
1064 if (tdev) {
1065 int t_hlen = tunnel->hlen + sizeof(struct iphdr);
1066
1067 dev->hard_header_len = tdev->hard_header_len + sizeof(struct iphdr);
1068 dev->mtu = tdev->mtu - t_hlen;
1069 if (dev->mtu < IPV6_MIN_MTU)
1070 dev->mtu = IPV6_MIN_MTU;
1071 }
1072 }
1073
1074 static void ipip6_tunnel_update(struct ip_tunnel *t, struct ip_tunnel_parm *p)
1075 {
1076 struct net *net = t->net;
1077 struct sit_net *sitn = net_generic(net, sit_net_id);
1078
1079 ipip6_tunnel_unlink(sitn, t);
1080 synchronize_net();
1081 t->parms.iph.saddr = p->iph.saddr;
1082 t->parms.iph.daddr = p->iph.daddr;
1083 memcpy(t->dev->dev_addr, &p->iph.saddr, 4);
1084 memcpy(t->dev->broadcast, &p->iph.daddr, 4);
1085 ipip6_tunnel_link(sitn, t);
1086 t->parms.iph.ttl = p->iph.ttl;
1087 t->parms.iph.tos = p->iph.tos;
1088 if (t->parms.link != p->link) {
1089 t->parms.link = p->link;
1090 ipip6_tunnel_bind_dev(t->dev);
1091 }
1092 dst_cache_reset(&t->dst_cache);
1093 netdev_state_change(t->dev);
1094 }
1095
1096 #ifdef CONFIG_IPV6_SIT_6RD
1097 static int ipip6_tunnel_update_6rd(struct ip_tunnel *t,
1098 struct ip_tunnel_6rd *ip6rd)
1099 {
1100 struct in6_addr prefix;
1101 __be32 relay_prefix;
1102
1103 if (ip6rd->relay_prefixlen > 32 ||
1104 ip6rd->prefixlen + (32 - ip6rd->relay_prefixlen) > 64)
1105 return -EINVAL;
1106
1107 ipv6_addr_prefix(&prefix, &ip6rd->prefix, ip6rd->prefixlen);
1108 if (!ipv6_addr_equal(&prefix, &ip6rd->prefix))
1109 return -EINVAL;
1110 if (ip6rd->relay_prefixlen)
1111 relay_prefix = ip6rd->relay_prefix &
1112 htonl(0xffffffffUL <<
1113 (32 - ip6rd->relay_prefixlen));
1114 else
1115 relay_prefix = 0;
1116 if (relay_prefix != ip6rd->relay_prefix)
1117 return -EINVAL;
1118
1119 t->ip6rd.prefix = prefix;
1120 t->ip6rd.relay_prefix = relay_prefix;
1121 t->ip6rd.prefixlen = ip6rd->prefixlen;
1122 t->ip6rd.relay_prefixlen = ip6rd->relay_prefixlen;
1123 dst_cache_reset(&t->dst_cache);
1124 netdev_state_change(t->dev);
1125 return 0;
1126 }
1127 #endif
1128
1129 bool ipip6_valid_ip_proto(u8 ipproto)
1130 {
1131 return ipproto == IPPROTO_IPV6 ||
1132 ipproto == IPPROTO_IPIP ||
1133 #if IS_ENABLED(CONFIG_MPLS)
1134 ipproto == IPPROTO_MPLS ||
1135 #endif
1136 ipproto == 0;
1137 }
1138
1139 static int
1140 ipip6_tunnel_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
1141 {
1142 int err = 0;
1143 struct ip_tunnel_parm p;
1144 struct ip_tunnel_prl prl;
1145 struct ip_tunnel *t = netdev_priv(dev);
1146 struct net *net = t->net;
1147 struct sit_net *sitn = net_generic(net, sit_net_id);
1148 #ifdef CONFIG_IPV6_SIT_6RD
1149 struct ip_tunnel_6rd ip6rd;
1150 #endif
1151
1152 switch (cmd) {
1153 case SIOCGETTUNNEL:
1154 #ifdef CONFIG_IPV6_SIT_6RD
1155 case SIOCGET6RD:
1156 #endif
1157 if (dev == sitn->fb_tunnel_dev) {
1158 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) {
1159 err = -EFAULT;
1160 break;
1161 }
1162 t = ipip6_tunnel_locate(net, &p, 0);
1163 if (!t)
1164 t = netdev_priv(dev);
1165 }
1166
1167 err = -EFAULT;
1168 if (cmd == SIOCGETTUNNEL) {
1169 memcpy(&p, &t->parms, sizeof(p));
1170 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p,
1171 sizeof(p)))
1172 goto done;
1173 #ifdef CONFIG_IPV6_SIT_6RD
1174 } else {
1175 ip6rd.prefix = t->ip6rd.prefix;
1176 ip6rd.relay_prefix = t->ip6rd.relay_prefix;
1177 ip6rd.prefixlen = t->ip6rd.prefixlen;
1178 ip6rd.relay_prefixlen = t->ip6rd.relay_prefixlen;
1179 if (copy_to_user(ifr->ifr_ifru.ifru_data, &ip6rd,
1180 sizeof(ip6rd)))
1181 goto done;
1182 #endif
1183 }
1184 err = 0;
1185 break;
1186
1187 case SIOCADDTUNNEL:
1188 case SIOCCHGTUNNEL:
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(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
1195 goto done;
1196
1197 err = -EINVAL;
1198 if (!ipip6_valid_ip_proto(p.iph.protocol))
1199 goto done;
1200 if (p.iph.version != 4 ||
1201 p.iph.ihl != 5 || (p.iph.frag_off&htons(~IP_DF)))
1202 goto done;
1203 if (p.iph.ttl)
1204 p.iph.frag_off |= htons(IP_DF);
1205
1206 t = ipip6_tunnel_locate(net, &p, cmd == SIOCADDTUNNEL);
1207
1208 if (dev != sitn->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) {
1209 if (t) {
1210 if (t->dev != dev) {
1211 err = -EEXIST;
1212 break;
1213 }
1214 } else {
1215 if (((dev->flags&IFF_POINTOPOINT) && !p.iph.daddr) ||
1216 (!(dev->flags&IFF_POINTOPOINT) && p.iph.daddr)) {
1217 err = -EINVAL;
1218 break;
1219 }
1220 t = netdev_priv(dev);
1221 }
1222
1223 ipip6_tunnel_update(t, &p);
1224 }
1225
1226 if (t) {
1227 err = 0;
1228 if (copy_to_user(ifr->ifr_ifru.ifru_data, &t->parms, sizeof(p)))
1229 err = -EFAULT;
1230 } else
1231 err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
1232 break;
1233
1234 case SIOCDELTUNNEL:
1235 err = -EPERM;
1236 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1237 goto done;
1238
1239 if (dev == sitn->fb_tunnel_dev) {
1240 err = -EFAULT;
1241 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
1242 goto done;
1243 err = -ENOENT;
1244 t = ipip6_tunnel_locate(net, &p, 0);
1245 if (!t)
1246 goto done;
1247 err = -EPERM;
1248 if (t == netdev_priv(sitn->fb_tunnel_dev))
1249 goto done;
1250 dev = t->dev;
1251 }
1252 unregister_netdevice(dev);
1253 err = 0;
1254 break;
1255
1256 case SIOCGETPRL:
1257 err = -EINVAL;
1258 if (dev == sitn->fb_tunnel_dev)
1259 goto done;
1260 err = ipip6_tunnel_get_prl(t, ifr->ifr_ifru.ifru_data);
1261 break;
1262
1263 case SIOCADDPRL:
1264 case SIOCDELPRL:
1265 case SIOCCHGPRL:
1266 err = -EPERM;
1267 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1268 goto done;
1269 err = -EINVAL;
1270 if (dev == sitn->fb_tunnel_dev)
1271 goto done;
1272 err = -EFAULT;
1273 if (copy_from_user(&prl, ifr->ifr_ifru.ifru_data, sizeof(prl)))
1274 goto done;
1275
1276 switch (cmd) {
1277 case SIOCDELPRL:
1278 err = ipip6_tunnel_del_prl(t, &prl);
1279 break;
1280 case SIOCADDPRL:
1281 case SIOCCHGPRL:
1282 err = ipip6_tunnel_add_prl(t, &prl, cmd == SIOCCHGPRL);
1283 break;
1284 }
1285 dst_cache_reset(&t->dst_cache);
1286 netdev_state_change(dev);
1287 break;
1288
1289 #ifdef CONFIG_IPV6_SIT_6RD
1290 case SIOCADD6RD:
1291 case SIOCCHG6RD:
1292 case SIOCDEL6RD:
1293 err = -EPERM;
1294 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1295 goto done;
1296
1297 err = -EFAULT;
1298 if (copy_from_user(&ip6rd, ifr->ifr_ifru.ifru_data,
1299 sizeof(ip6rd)))
1300 goto done;
1301
1302 if (cmd != SIOCDEL6RD) {
1303 err = ipip6_tunnel_update_6rd(t, &ip6rd);
1304 if (err < 0)
1305 goto done;
1306 } else
1307 ipip6_tunnel_clone_6rd(dev, sitn);
1308
1309 err = 0;
1310 break;
1311 #endif
1312
1313 default:
1314 err = -EINVAL;
1315 }
1316
1317 done:
1318 return err;
1319 }
1320
1321 static int ipip6_tunnel_change_mtu(struct net_device *dev, int new_mtu)
1322 {
1323 struct ip_tunnel *tunnel = netdev_priv(dev);
1324 int t_hlen = tunnel->hlen + sizeof(struct iphdr);
1325
1326 if (new_mtu < IPV6_MIN_MTU || new_mtu > 0xFFF8 - t_hlen)
1327 return -EINVAL;
1328 dev->mtu = new_mtu;
1329 return 0;
1330 }
1331
1332 static const struct net_device_ops ipip6_netdev_ops = {
1333 .ndo_init = ipip6_tunnel_init,
1334 .ndo_uninit = ipip6_tunnel_uninit,
1335 .ndo_start_xmit = sit_tunnel_xmit,
1336 .ndo_do_ioctl = ipip6_tunnel_ioctl,
1337 .ndo_change_mtu = ipip6_tunnel_change_mtu,
1338 .ndo_get_stats64 = ip_tunnel_get_stats64,
1339 .ndo_get_iflink = ip_tunnel_get_iflink,
1340 };
1341
1342 static void ipip6_dev_free(struct net_device *dev)
1343 {
1344 struct ip_tunnel *tunnel = netdev_priv(dev);
1345
1346 dst_cache_destroy(&tunnel->dst_cache);
1347 free_percpu(dev->tstats);
1348 free_netdev(dev);
1349 }
1350
1351 #define SIT_FEATURES (NETIF_F_SG | \
1352 NETIF_F_FRAGLIST | \
1353 NETIF_F_HIGHDMA | \
1354 NETIF_F_GSO_SOFTWARE | \
1355 NETIF_F_HW_CSUM)
1356
1357 static void ipip6_tunnel_setup(struct net_device *dev)
1358 {
1359 struct ip_tunnel *tunnel = netdev_priv(dev);
1360 int t_hlen = tunnel->hlen + sizeof(struct iphdr);
1361
1362 dev->netdev_ops = &ipip6_netdev_ops;
1363 dev->destructor = ipip6_dev_free;
1364
1365 dev->type = ARPHRD_SIT;
1366 dev->hard_header_len = LL_MAX_HEADER + t_hlen;
1367 dev->mtu = ETH_DATA_LEN - t_hlen;
1368 dev->flags = IFF_NOARP;
1369 netif_keep_dst(dev);
1370 dev->addr_len = 4;
1371 dev->features |= NETIF_F_LLTX;
1372 dev->features |= SIT_FEATURES;
1373 dev->hw_features |= SIT_FEATURES;
1374 }
1375
1376 static int ipip6_tunnel_init(struct net_device *dev)
1377 {
1378 struct ip_tunnel *tunnel = netdev_priv(dev);
1379 int err;
1380
1381 tunnel->dev = dev;
1382 tunnel->net = dev_net(dev);
1383 strcpy(tunnel->parms.name, dev->name);
1384
1385 ipip6_tunnel_bind_dev(dev);
1386 dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
1387 if (!dev->tstats)
1388 return -ENOMEM;
1389
1390 err = dst_cache_init(&tunnel->dst_cache, GFP_KERNEL);
1391 if (err) {
1392 free_percpu(dev->tstats);
1393 return err;
1394 }
1395
1396 return 0;
1397 }
1398
1399 static void __net_init ipip6_fb_tunnel_init(struct net_device *dev)
1400 {
1401 struct ip_tunnel *tunnel = netdev_priv(dev);
1402 struct iphdr *iph = &tunnel->parms.iph;
1403 struct net *net = dev_net(dev);
1404 struct sit_net *sitn = net_generic(net, sit_net_id);
1405
1406 iph->version = 4;
1407 iph->protocol = IPPROTO_IPV6;
1408 iph->ihl = 5;
1409 iph->ttl = 64;
1410
1411 dev_hold(dev);
1412 rcu_assign_pointer(sitn->tunnels_wc[0], tunnel);
1413 }
1414
1415 static int ipip6_validate(struct nlattr *tb[], struct nlattr *data[])
1416 {
1417 u8 proto;
1418
1419 if (!data || !data[IFLA_IPTUN_PROTO])
1420 return 0;
1421
1422 proto = nla_get_u8(data[IFLA_IPTUN_PROTO]);
1423 if (!ipip6_valid_ip_proto(proto))
1424 return -EINVAL;
1425
1426 return 0;
1427 }
1428
1429 static void ipip6_netlink_parms(struct nlattr *data[],
1430 struct ip_tunnel_parm *parms)
1431 {
1432 memset(parms, 0, sizeof(*parms));
1433
1434 parms->iph.version = 4;
1435 parms->iph.protocol = IPPROTO_IPV6;
1436 parms->iph.ihl = 5;
1437 parms->iph.ttl = 64;
1438
1439 if (!data)
1440 return;
1441
1442 if (data[IFLA_IPTUN_LINK])
1443 parms->link = nla_get_u32(data[IFLA_IPTUN_LINK]);
1444
1445 if (data[IFLA_IPTUN_LOCAL])
1446 parms->iph.saddr = nla_get_be32(data[IFLA_IPTUN_LOCAL]);
1447
1448 if (data[IFLA_IPTUN_REMOTE])
1449 parms->iph.daddr = nla_get_be32(data[IFLA_IPTUN_REMOTE]);
1450
1451 if (data[IFLA_IPTUN_TTL]) {
1452 parms->iph.ttl = nla_get_u8(data[IFLA_IPTUN_TTL]);
1453 if (parms->iph.ttl)
1454 parms->iph.frag_off = htons(IP_DF);
1455 }
1456
1457 if (data[IFLA_IPTUN_TOS])
1458 parms->iph.tos = nla_get_u8(data[IFLA_IPTUN_TOS]);
1459
1460 if (!data[IFLA_IPTUN_PMTUDISC] || nla_get_u8(data[IFLA_IPTUN_PMTUDISC]))
1461 parms->iph.frag_off = htons(IP_DF);
1462
1463 if (data[IFLA_IPTUN_FLAGS])
1464 parms->i_flags = nla_get_be16(data[IFLA_IPTUN_FLAGS]);
1465
1466 if (data[IFLA_IPTUN_PROTO])
1467 parms->iph.protocol = nla_get_u8(data[IFLA_IPTUN_PROTO]);
1468
1469 }
1470
1471 /* This function returns true when ENCAP attributes are present in the nl msg */
1472 static bool ipip6_netlink_encap_parms(struct nlattr *data[],
1473 struct ip_tunnel_encap *ipencap)
1474 {
1475 bool ret = false;
1476
1477 memset(ipencap, 0, sizeof(*ipencap));
1478
1479 if (!data)
1480 return ret;
1481
1482 if (data[IFLA_IPTUN_ENCAP_TYPE]) {
1483 ret = true;
1484 ipencap->type = nla_get_u16(data[IFLA_IPTUN_ENCAP_TYPE]);
1485 }
1486
1487 if (data[IFLA_IPTUN_ENCAP_FLAGS]) {
1488 ret = true;
1489 ipencap->flags = nla_get_u16(data[IFLA_IPTUN_ENCAP_FLAGS]);
1490 }
1491
1492 if (data[IFLA_IPTUN_ENCAP_SPORT]) {
1493 ret = true;
1494 ipencap->sport = nla_get_be16(data[IFLA_IPTUN_ENCAP_SPORT]);
1495 }
1496
1497 if (data[IFLA_IPTUN_ENCAP_DPORT]) {
1498 ret = true;
1499 ipencap->dport = nla_get_be16(data[IFLA_IPTUN_ENCAP_DPORT]);
1500 }
1501
1502 return ret;
1503 }
1504
1505 #ifdef CONFIG_IPV6_SIT_6RD
1506 /* This function returns true when 6RD attributes are present in the nl msg */
1507 static bool ipip6_netlink_6rd_parms(struct nlattr *data[],
1508 struct ip_tunnel_6rd *ip6rd)
1509 {
1510 bool ret = false;
1511 memset(ip6rd, 0, sizeof(*ip6rd));
1512
1513 if (!data)
1514 return ret;
1515
1516 if (data[IFLA_IPTUN_6RD_PREFIX]) {
1517 ret = true;
1518 ip6rd->prefix = nla_get_in6_addr(data[IFLA_IPTUN_6RD_PREFIX]);
1519 }
1520
1521 if (data[IFLA_IPTUN_6RD_RELAY_PREFIX]) {
1522 ret = true;
1523 ip6rd->relay_prefix =
1524 nla_get_be32(data[IFLA_IPTUN_6RD_RELAY_PREFIX]);
1525 }
1526
1527 if (data[IFLA_IPTUN_6RD_PREFIXLEN]) {
1528 ret = true;
1529 ip6rd->prefixlen = nla_get_u16(data[IFLA_IPTUN_6RD_PREFIXLEN]);
1530 }
1531
1532 if (data[IFLA_IPTUN_6RD_RELAY_PREFIXLEN]) {
1533 ret = true;
1534 ip6rd->relay_prefixlen =
1535 nla_get_u16(data[IFLA_IPTUN_6RD_RELAY_PREFIXLEN]);
1536 }
1537
1538 return ret;
1539 }
1540 #endif
1541
1542 static int ipip6_newlink(struct net *src_net, struct net_device *dev,
1543 struct nlattr *tb[], struct nlattr *data[])
1544 {
1545 struct net *net = dev_net(dev);
1546 struct ip_tunnel *nt;
1547 struct ip_tunnel_encap ipencap;
1548 #ifdef CONFIG_IPV6_SIT_6RD
1549 struct ip_tunnel_6rd ip6rd;
1550 #endif
1551 int err;
1552
1553 nt = netdev_priv(dev);
1554
1555 if (ipip6_netlink_encap_parms(data, &ipencap)) {
1556 err = ip_tunnel_encap_setup(nt, &ipencap);
1557 if (err < 0)
1558 return err;
1559 }
1560
1561 ipip6_netlink_parms(data, &nt->parms);
1562
1563 if (ipip6_tunnel_locate(net, &nt->parms, 0))
1564 return -EEXIST;
1565
1566 err = ipip6_tunnel_create(dev);
1567 if (err < 0)
1568 return err;
1569
1570 #ifdef CONFIG_IPV6_SIT_6RD
1571 if (ipip6_netlink_6rd_parms(data, &ip6rd))
1572 err = ipip6_tunnel_update_6rd(nt, &ip6rd);
1573 #endif
1574
1575 return err;
1576 }
1577
1578 static int ipip6_changelink(struct net_device *dev, struct nlattr *tb[],
1579 struct nlattr *data[])
1580 {
1581 struct ip_tunnel *t = netdev_priv(dev);
1582 struct ip_tunnel_parm p;
1583 struct ip_tunnel_encap ipencap;
1584 struct net *net = t->net;
1585 struct sit_net *sitn = net_generic(net, sit_net_id);
1586 #ifdef CONFIG_IPV6_SIT_6RD
1587 struct ip_tunnel_6rd ip6rd;
1588 #endif
1589 int err;
1590
1591 if (dev == sitn->fb_tunnel_dev)
1592 return -EINVAL;
1593
1594 if (ipip6_netlink_encap_parms(data, &ipencap)) {
1595 err = ip_tunnel_encap_setup(t, &ipencap);
1596 if (err < 0)
1597 return err;
1598 }
1599
1600 ipip6_netlink_parms(data, &p);
1601
1602 if (((dev->flags & IFF_POINTOPOINT) && !p.iph.daddr) ||
1603 (!(dev->flags & IFF_POINTOPOINT) && p.iph.daddr))
1604 return -EINVAL;
1605
1606 t = ipip6_tunnel_locate(net, &p, 0);
1607
1608 if (t) {
1609 if (t->dev != dev)
1610 return -EEXIST;
1611 } else
1612 t = netdev_priv(dev);
1613
1614 ipip6_tunnel_update(t, &p);
1615
1616 #ifdef CONFIG_IPV6_SIT_6RD
1617 if (ipip6_netlink_6rd_parms(data, &ip6rd))
1618 return ipip6_tunnel_update_6rd(t, &ip6rd);
1619 #endif
1620
1621 return 0;
1622 }
1623
1624 static size_t ipip6_get_size(const struct net_device *dev)
1625 {
1626 return
1627 /* IFLA_IPTUN_LINK */
1628 nla_total_size(4) +
1629 /* IFLA_IPTUN_LOCAL */
1630 nla_total_size(4) +
1631 /* IFLA_IPTUN_REMOTE */
1632 nla_total_size(4) +
1633 /* IFLA_IPTUN_TTL */
1634 nla_total_size(1) +
1635 /* IFLA_IPTUN_TOS */
1636 nla_total_size(1) +
1637 /* IFLA_IPTUN_PMTUDISC */
1638 nla_total_size(1) +
1639 /* IFLA_IPTUN_FLAGS */
1640 nla_total_size(2) +
1641 /* IFLA_IPTUN_PROTO */
1642 nla_total_size(1) +
1643 #ifdef CONFIG_IPV6_SIT_6RD
1644 /* IFLA_IPTUN_6RD_PREFIX */
1645 nla_total_size(sizeof(struct in6_addr)) +
1646 /* IFLA_IPTUN_6RD_RELAY_PREFIX */
1647 nla_total_size(4) +
1648 /* IFLA_IPTUN_6RD_PREFIXLEN */
1649 nla_total_size(2) +
1650 /* IFLA_IPTUN_6RD_RELAY_PREFIXLEN */
1651 nla_total_size(2) +
1652 #endif
1653 /* IFLA_IPTUN_ENCAP_TYPE */
1654 nla_total_size(2) +
1655 /* IFLA_IPTUN_ENCAP_FLAGS */
1656 nla_total_size(2) +
1657 /* IFLA_IPTUN_ENCAP_SPORT */
1658 nla_total_size(2) +
1659 /* IFLA_IPTUN_ENCAP_DPORT */
1660 nla_total_size(2) +
1661 0;
1662 }
1663
1664 static int ipip6_fill_info(struct sk_buff *skb, const struct net_device *dev)
1665 {
1666 struct ip_tunnel *tunnel = netdev_priv(dev);
1667 struct ip_tunnel_parm *parm = &tunnel->parms;
1668
1669 if (nla_put_u32(skb, IFLA_IPTUN_LINK, parm->link) ||
1670 nla_put_in_addr(skb, IFLA_IPTUN_LOCAL, parm->iph.saddr) ||
1671 nla_put_in_addr(skb, IFLA_IPTUN_REMOTE, parm->iph.daddr) ||
1672 nla_put_u8(skb, IFLA_IPTUN_TTL, parm->iph.ttl) ||
1673 nla_put_u8(skb, IFLA_IPTUN_TOS, parm->iph.tos) ||
1674 nla_put_u8(skb, IFLA_IPTUN_PMTUDISC,
1675 !!(parm->iph.frag_off & htons(IP_DF))) ||
1676 nla_put_u8(skb, IFLA_IPTUN_PROTO, parm->iph.protocol) ||
1677 nla_put_be16(skb, IFLA_IPTUN_FLAGS, parm->i_flags))
1678 goto nla_put_failure;
1679
1680 #ifdef CONFIG_IPV6_SIT_6RD
1681 if (nla_put_in6_addr(skb, IFLA_IPTUN_6RD_PREFIX,
1682 &tunnel->ip6rd.prefix) ||
1683 nla_put_in_addr(skb, IFLA_IPTUN_6RD_RELAY_PREFIX,
1684 tunnel->ip6rd.relay_prefix) ||
1685 nla_put_u16(skb, IFLA_IPTUN_6RD_PREFIXLEN,
1686 tunnel->ip6rd.prefixlen) ||
1687 nla_put_u16(skb, IFLA_IPTUN_6RD_RELAY_PREFIXLEN,
1688 tunnel->ip6rd.relay_prefixlen))
1689 goto nla_put_failure;
1690 #endif
1691
1692 if (nla_put_u16(skb, IFLA_IPTUN_ENCAP_TYPE,
1693 tunnel->encap.type) ||
1694 nla_put_be16(skb, IFLA_IPTUN_ENCAP_SPORT,
1695 tunnel->encap.sport) ||
1696 nla_put_be16(skb, IFLA_IPTUN_ENCAP_DPORT,
1697 tunnel->encap.dport) ||
1698 nla_put_u16(skb, IFLA_IPTUN_ENCAP_FLAGS,
1699 tunnel->encap.flags))
1700 goto nla_put_failure;
1701
1702 return 0;
1703
1704 nla_put_failure:
1705 return -EMSGSIZE;
1706 }
1707
1708 static const struct nla_policy ipip6_policy[IFLA_IPTUN_MAX + 1] = {
1709 [IFLA_IPTUN_LINK] = { .type = NLA_U32 },
1710 [IFLA_IPTUN_LOCAL] = { .type = NLA_U32 },
1711 [IFLA_IPTUN_REMOTE] = { .type = NLA_U32 },
1712 [IFLA_IPTUN_TTL] = { .type = NLA_U8 },
1713 [IFLA_IPTUN_TOS] = { .type = NLA_U8 },
1714 [IFLA_IPTUN_PMTUDISC] = { .type = NLA_U8 },
1715 [IFLA_IPTUN_FLAGS] = { .type = NLA_U16 },
1716 [IFLA_IPTUN_PROTO] = { .type = NLA_U8 },
1717 #ifdef CONFIG_IPV6_SIT_6RD
1718 [IFLA_IPTUN_6RD_PREFIX] = { .len = sizeof(struct in6_addr) },
1719 [IFLA_IPTUN_6RD_RELAY_PREFIX] = { .type = NLA_U32 },
1720 [IFLA_IPTUN_6RD_PREFIXLEN] = { .type = NLA_U16 },
1721 [IFLA_IPTUN_6RD_RELAY_PREFIXLEN] = { .type = NLA_U16 },
1722 #endif
1723 [IFLA_IPTUN_ENCAP_TYPE] = { .type = NLA_U16 },
1724 [IFLA_IPTUN_ENCAP_FLAGS] = { .type = NLA_U16 },
1725 [IFLA_IPTUN_ENCAP_SPORT] = { .type = NLA_U16 },
1726 [IFLA_IPTUN_ENCAP_DPORT] = { .type = NLA_U16 },
1727 };
1728
1729 static void ipip6_dellink(struct net_device *dev, struct list_head *head)
1730 {
1731 struct net *net = dev_net(dev);
1732 struct sit_net *sitn = net_generic(net, sit_net_id);
1733
1734 if (dev != sitn->fb_tunnel_dev)
1735 unregister_netdevice_queue(dev, head);
1736 }
1737
1738 static struct rtnl_link_ops sit_link_ops __read_mostly = {
1739 .kind = "sit",
1740 .maxtype = IFLA_IPTUN_MAX,
1741 .policy = ipip6_policy,
1742 .priv_size = sizeof(struct ip_tunnel),
1743 .setup = ipip6_tunnel_setup,
1744 .validate = ipip6_validate,
1745 .newlink = ipip6_newlink,
1746 .changelink = ipip6_changelink,
1747 .get_size = ipip6_get_size,
1748 .fill_info = ipip6_fill_info,
1749 .dellink = ipip6_dellink,
1750 .get_link_net = ip_tunnel_get_link_net,
1751 };
1752
1753 static struct xfrm_tunnel sit_handler __read_mostly = {
1754 .handler = ipip6_rcv,
1755 .err_handler = ipip6_err,
1756 .priority = 1,
1757 };
1758
1759 static struct xfrm_tunnel ipip_handler __read_mostly = {
1760 .handler = ipip_rcv,
1761 .err_handler = ipip6_err,
1762 .priority = 2,
1763 };
1764
1765 #if IS_ENABLED(CONFIG_MPLS)
1766 static struct xfrm_tunnel mplsip_handler __read_mostly = {
1767 .handler = mplsip_rcv,
1768 .err_handler = ipip6_err,
1769 .priority = 2,
1770 };
1771 #endif
1772
1773 static void __net_exit sit_destroy_tunnels(struct net *net,
1774 struct list_head *head)
1775 {
1776 struct sit_net *sitn = net_generic(net, sit_net_id);
1777 struct net_device *dev, *aux;
1778 int prio;
1779
1780 for_each_netdev_safe(net, dev, aux)
1781 if (dev->rtnl_link_ops == &sit_link_ops)
1782 unregister_netdevice_queue(dev, head);
1783
1784 for (prio = 1; prio < 4; prio++) {
1785 int h;
1786 for (h = 0; h < HASH_SIZE; h++) {
1787 struct ip_tunnel *t;
1788
1789 t = rtnl_dereference(sitn->tunnels[prio][h]);
1790 while (t) {
1791 /* If dev is in the same netns, it has already
1792 * been added to the list by the previous loop.
1793 */
1794 if (!net_eq(dev_net(t->dev), net))
1795 unregister_netdevice_queue(t->dev,
1796 head);
1797 t = rtnl_dereference(t->next);
1798 }
1799 }
1800 }
1801 }
1802
1803 static int __net_init sit_init_net(struct net *net)
1804 {
1805 struct sit_net *sitn = net_generic(net, sit_net_id);
1806 struct ip_tunnel *t;
1807 int err;
1808
1809 sitn->tunnels[0] = sitn->tunnels_wc;
1810 sitn->tunnels[1] = sitn->tunnels_l;
1811 sitn->tunnels[2] = sitn->tunnels_r;
1812 sitn->tunnels[3] = sitn->tunnels_r_l;
1813
1814 sitn->fb_tunnel_dev = alloc_netdev(sizeof(struct ip_tunnel), "sit0",
1815 NET_NAME_UNKNOWN,
1816 ipip6_tunnel_setup);
1817 if (!sitn->fb_tunnel_dev) {
1818 err = -ENOMEM;
1819 goto err_alloc_dev;
1820 }
1821 dev_net_set(sitn->fb_tunnel_dev, net);
1822 sitn->fb_tunnel_dev->rtnl_link_ops = &sit_link_ops;
1823 /* FB netdevice is special: we have one, and only one per netns.
1824 * Allowing to move it to another netns is clearly unsafe.
1825 */
1826 sitn->fb_tunnel_dev->features |= NETIF_F_NETNS_LOCAL;
1827
1828 err = register_netdev(sitn->fb_tunnel_dev);
1829 if (err)
1830 goto err_reg_dev;
1831
1832 ipip6_tunnel_clone_6rd(sitn->fb_tunnel_dev, sitn);
1833 ipip6_fb_tunnel_init(sitn->fb_tunnel_dev);
1834
1835 t = netdev_priv(sitn->fb_tunnel_dev);
1836
1837 strcpy(t->parms.name, sitn->fb_tunnel_dev->name);
1838 return 0;
1839
1840 err_reg_dev:
1841 ipip6_dev_free(sitn->fb_tunnel_dev);
1842 err_alloc_dev:
1843 return err;
1844 }
1845
1846 static void __net_exit sit_exit_net(struct net *net)
1847 {
1848 LIST_HEAD(list);
1849
1850 rtnl_lock();
1851 sit_destroy_tunnels(net, &list);
1852 unregister_netdevice_many(&list);
1853 rtnl_unlock();
1854 }
1855
1856 static struct pernet_operations sit_net_ops = {
1857 .init = sit_init_net,
1858 .exit = sit_exit_net,
1859 .id = &sit_net_id,
1860 .size = sizeof(struct sit_net),
1861 };
1862
1863 static void __exit sit_cleanup(void)
1864 {
1865 rtnl_link_unregister(&sit_link_ops);
1866 xfrm4_tunnel_deregister(&sit_handler, AF_INET6);
1867 xfrm4_tunnel_deregister(&ipip_handler, AF_INET);
1868 #if IS_ENABLED(CONFIG_MPLS)
1869 xfrm4_tunnel_deregister(&mplsip_handler, AF_MPLS);
1870 #endif
1871
1872 unregister_pernet_device(&sit_net_ops);
1873 rcu_barrier(); /* Wait for completion of call_rcu()'s */
1874 }
1875
1876 static int __init sit_init(void)
1877 {
1878 int err;
1879
1880 pr_info("IPv6, IPv4 and MPLS over IPv4 tunneling driver\n");
1881
1882 err = register_pernet_device(&sit_net_ops);
1883 if (err < 0)
1884 return err;
1885 err = xfrm4_tunnel_register(&sit_handler, AF_INET6);
1886 if (err < 0) {
1887 pr_info("%s: can't register ip6ip4\n", __func__);
1888 goto xfrm_tunnel_failed;
1889 }
1890 err = xfrm4_tunnel_register(&ipip_handler, AF_INET);
1891 if (err < 0) {
1892 pr_info("%s: can't register ip4ip4\n", __func__);
1893 goto xfrm_tunnel4_failed;
1894 }
1895 #if IS_ENABLED(CONFIG_MPLS)
1896 err = xfrm4_tunnel_register(&mplsip_handler, AF_MPLS);
1897 if (err < 0) {
1898 pr_info("%s: can't register mplsip\n", __func__);
1899 goto xfrm_tunnel_mpls_failed;
1900 }
1901 #endif
1902 err = rtnl_link_register(&sit_link_ops);
1903 if (err < 0)
1904 goto rtnl_link_failed;
1905
1906 out:
1907 return err;
1908
1909 rtnl_link_failed:
1910 #if IS_ENABLED(CONFIG_MPLS)
1911 xfrm4_tunnel_deregister(&mplsip_handler, AF_MPLS);
1912 xfrm_tunnel_mpls_failed:
1913 #endif
1914 xfrm4_tunnel_deregister(&ipip_handler, AF_INET);
1915 xfrm_tunnel4_failed:
1916 xfrm4_tunnel_deregister(&sit_handler, AF_INET6);
1917 xfrm_tunnel_failed:
1918 unregister_pernet_device(&sit_net_ops);
1919 goto out;
1920 }
1921
1922 module_init(sit_init);
1923 module_exit(sit_cleanup);
1924 MODULE_LICENSE("GPL");
1925 MODULE_ALIAS_RTNL_LINK("sit");
1926 MODULE_ALIAS_NETDEV("sit0");
Linux with added FPC-III support