1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * IPv6 over IPv4 tunnel device - Simple Internet Transition (SIT)
4 * Linux INET6 implementation
5 *
6 * Authors:
7 * Pedro Roque <roque@di.fc.ul.pt>
8 * Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
9 *
10 * Changes:
11 * Roger Venning <r.venning@telstra.com>: 6to4 support
12 * Nate Thompson <nate@thebog.net>: 6to4 support
13 * Fred Templin <fred.l.templin@boeing.com>: isatap support
14 */
15
16#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
17
18#include <linux/module.h>
19#include <linux/capability.h>
20#include <linux/errno.h>
21#include <linux/types.h>
22#include <linux/socket.h>
23#include <linux/sockios.h>
24#include <linux/net.h>
25#include <linux/in6.h>
26#include <linux/netdevice.h>
27#include <linux/if_arp.h>
28#include <linux/icmp.h>
29#include <linux/slab.h>
30#include <linux/uaccess.h>
31#include <linux/init.h>
32#include <linux/netfilter_ipv4.h>
33#include <linux/if_ether.h>
34
35#include <net/sock.h>
36#include <net/snmp.h>
37
38#include <net/ipv6.h>
39#include <net/protocol.h>
40#include <net/transp_v6.h>
41#include <net/ip6_fib.h>
42#include <net/ip6_route.h>
43#include <net/ndisc.h>
44#include <net/addrconf.h>
45#include <net/ip.h>
46#include <net/udp.h>
47#include <net/icmp.h>
48#include <net/ip_tunnels.h>
49#include <net/inet_ecn.h>
50#include <net/xfrm.h>
51#include <net/dsfield.h>
52#include <net/net_namespace.h>
53#include <net/netns/generic.h>
54#include <net/netdev_lock.h>
55#include <net/inet_dscp.h>
56
57/*
58 This version of net/ipv6/sit.c is cloned of net/ipv4/ip_gre.c
59
60 For comments look at net/ipv4/ip_gre.c --ANK
61 */
62
63#define IP6_SIT_HASH_SIZE 16
64#define HASH(addr) (((__force u32)addr^((__force u32)addr>>4))&0xF)
65
66static bool log_ecn_error = true;
67module_param(log_ecn_error, bool, 0644);
68MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN");
69
70static int ipip6_tunnel_init(struct net_device *dev);
71static void ipip6_tunnel_setup(struct net_device *dev);
72static void ipip6_dev_free(struct net_device *dev);
73static bool check_6rd(struct ip_tunnel *tunnel, const struct in6_addr *v6dst,
74 __be32 *v4dst);
75static struct rtnl_link_ops sit_link_ops __read_mostly;
76
77static unsigned int sit_net_id __read_mostly;
78struct sit_net {
79 struct ip_tunnel __rcu *tunnels_r_l[IP6_SIT_HASH_SIZE];
80 struct ip_tunnel __rcu *tunnels_r[IP6_SIT_HASH_SIZE];
81 struct ip_tunnel __rcu *tunnels_l[IP6_SIT_HASH_SIZE];
82 struct ip_tunnel __rcu *tunnels_wc[1];
83 struct ip_tunnel __rcu **tunnels[4];
84
85 struct net_device *fb_tunnel_dev;
86};
87
88static inline struct sit_net *dev_to_sit_net(struct net_device *dev)
89{
90 struct ip_tunnel *t = netdev_priv(dev);
91
92 return net_generic(net: t->net, id: sit_net_id);
93}
94
95/*
96 * Must be invoked with rcu_read_lock
97 */
98static struct ip_tunnel *ipip6_tunnel_lookup(struct net *net,
99 struct net_device *dev,
100 __be32 remote, __be32 local,
101 int sifindex)
102{
103 unsigned int h0 = HASH(remote);
104 unsigned int h1 = HASH(local);
105 struct ip_tunnel *t;
106 struct sit_net *sitn = net_generic(net, id: sit_net_id);
107 int ifindex = dev ? dev->ifindex : 0;
108
109 for_each_ip_tunnel_rcu(t, sitn->tunnels_r_l[h0 ^ h1]) {
110 if (local == t->parms.iph.saddr &&
111 remote == t->parms.iph.daddr &&
112 (!dev || !t->parms.link || ifindex == t->parms.link ||
113 sifindex == t->parms.link) &&
114 (t->dev->flags & IFF_UP))
115 return t;
116 }
117 for_each_ip_tunnel_rcu(t, sitn->tunnels_r[h0]) {
118 if (remote == t->parms.iph.daddr &&
119 (!dev || !t->parms.link || ifindex == t->parms.link ||
120 sifindex == t->parms.link) &&
121 (t->dev->flags & IFF_UP))
122 return t;
123 }
124 for_each_ip_tunnel_rcu(t, sitn->tunnels_l[h1]) {
125 if (local == t->parms.iph.saddr &&
126 (!dev || !t->parms.link || ifindex == t->parms.link ||
127 sifindex == t->parms.link) &&
128 (t->dev->flags & IFF_UP))
129 return t;
130 }
131 t = rcu_dereference(sitn->tunnels_wc[0]);
132 if (t && (t->dev->flags & IFF_UP))
133 return t;
134 return NULL;
135}
136
137static struct ip_tunnel __rcu **
138__ipip6_bucket(struct sit_net *sitn, struct ip_tunnel_parm_kern *parms)
139{
140 __be32 remote = parms->iph.daddr;
141 __be32 local = parms->iph.saddr;
142 unsigned int h = 0;
143 int prio = 0;
144
145 if (remote) {
146 prio |= 2;
147 h ^= HASH(remote);
148 }
149 if (local) {
150 prio |= 1;
151 h ^= HASH(local);
152 }
153 return &sitn->tunnels[prio][h];
154}
155
156static inline struct ip_tunnel __rcu **ipip6_bucket(struct sit_net *sitn,
157 struct ip_tunnel *t)
158{
159 return __ipip6_bucket(sitn, parms: &t->parms);
160}
161
162static void ipip6_tunnel_unlink(struct sit_net *sitn, struct ip_tunnel *t)
163{
164 struct ip_tunnel __rcu **tp;
165 struct ip_tunnel *iter;
166
167 for (tp = ipip6_bucket(sitn, t);
168 (iter = rtnl_dereference(*tp)) != NULL;
169 tp = &iter->next) {
170 if (t == iter) {
171 rcu_assign_pointer(*tp, t->next);
172 break;
173 }
174 }
175}
176
177static void ipip6_tunnel_link(struct sit_net *sitn, struct ip_tunnel *t)
178{
179 struct ip_tunnel __rcu **tp = ipip6_bucket(sitn, t);
180
181 rcu_assign_pointer(t->next, rtnl_dereference(*tp));
182 rcu_assign_pointer(*tp, t);
183}
184
185static void ipip6_tunnel_clone_6rd(struct net_device *dev, struct sit_net *sitn)
186{
187#ifdef CONFIG_IPV6_SIT_6RD
188 struct ip_tunnel *t = netdev_priv(dev);
189
190 if (dev == sitn->fb_tunnel_dev || !sitn->fb_tunnel_dev) {
191 ipv6_addr_set(&t->ip6rd.prefix, htonl(0x20020000), 0, 0, 0);
192 t->ip6rd.relay_prefix = 0;
193 t->ip6rd.prefixlen = 16;
194 t->ip6rd.relay_prefixlen = 0;
195 } else {
196 struct ip_tunnel *t0 = netdev_priv(sitn->fb_tunnel_dev);
197 memcpy(&t->ip6rd, &t0->ip6rd, sizeof(t->ip6rd));
198 }
199#endif
200}
201
202static int ipip6_tunnel_create(struct net_device *dev)
203{
204 struct ip_tunnel *t = netdev_priv(dev);
205 struct sit_net *sitn = net_generic(net: t->net, id: sit_net_id);
206 int err;
207
208 __dev_addr_set(dev, addr: &t->parms.iph.saddr, len: 4);
209 memcpy(to: dev->broadcast, from: &t->parms.iph.daddr, len: 4);
210
211 if (test_bit(IP_TUNNEL_SIT_ISATAP_BIT, t->parms.i_flags))
212 dev->priv_flags |= IFF_ISATAP;
213
214 dev->rtnl_link_ops = &sit_link_ops;
215
216 err = register_netdevice(dev);
217 if (err < 0)
218 goto out;
219
220 ipip6_tunnel_clone_6rd(dev, sitn);
221
222 ipip6_tunnel_link(sitn, t);
223 return 0;
224
225out:
226 return err;
227}
228
229static struct ip_tunnel *ipip6_tunnel_locate(struct net *net,
230 struct ip_tunnel_parm_kern *parms,
231 int create)
232{
233 __be32 remote = parms->iph.daddr;
234 __be32 local = parms->iph.saddr;
235 struct ip_tunnel *t, *nt;
236 struct ip_tunnel __rcu **tp;
237 struct net_device *dev;
238 char name[IFNAMSIZ];
239 struct sit_net *sitn = net_generic(net, id: sit_net_id);
240
241 for (tp = __ipip6_bucket(sitn, parms);
242 (t = rtnl_dereference(*tp)) != NULL;
243 tp = &t->next) {
244 if (local == t->parms.iph.saddr &&
245 remote == t->parms.iph.daddr &&
246 parms->link == t->parms.link) {
247 if (create)
248 return NULL;
249 else
250 return t;
251 }
252 }
253 if (!create)
254 goto failed;
255
256 if (parms->name[0]) {
257 if (!dev_valid_name(name: parms->name))
258 goto failed;
259 strscpy(name, parms->name, IFNAMSIZ);
260 } else {
261 strcpy(name, "sit%d");
262 }
263 dev = alloc_netdev(sizeof(*t), name, NET_NAME_UNKNOWN,
264 ipip6_tunnel_setup);
265 if (!dev)
266 return NULL;
267
268 dev_net_set(dev, net);
269
270 nt = netdev_priv(dev);
271
272 nt->net = net;
273 nt->parms = *parms;
274 if (ipip6_tunnel_create(dev) < 0)
275 goto failed_free;
276
277 if (!parms->name[0])
278 strcpy(parms->name, dev->name);
279
280 return nt;
281
282failed_free:
283 free_netdev(dev);
284failed:
285 return NULL;
286}
287
288#define for_each_prl_rcu(start) \
289 for (prl = rcu_dereference(start); \
290 prl; \
291 prl = rcu_dereference(prl->next))
292
293static struct ip_tunnel_prl_entry *
294__ipip6_tunnel_locate_prl(struct ip_tunnel *t, __be32 addr)
295{
296 struct ip_tunnel_prl_entry *prl;
297
298 for_each_prl_rcu(t->prl)
299 if (prl->addr == addr)
300 break;
301 return prl;
302
303}
304
305static int ipip6_tunnel_get_prl(struct net_device *dev, struct ip_tunnel_prl __user *a)
306{
307 struct ip_tunnel *t = netdev_priv(dev);
308 struct ip_tunnel_prl kprl, *kp;
309 struct ip_tunnel_prl_entry *prl;
310 unsigned int cmax, c = 0, ca, len;
311 int ret = 0;
312
313 if (dev == dev_to_sit_net(dev)->fb_tunnel_dev)
314 return -EINVAL;
315
316 if (copy_from_user(to: &kprl, from: a, n: sizeof(kprl)))
317 return -EFAULT;
318 cmax = kprl.datalen / sizeof(kprl);
319 if (cmax > 1 && kprl.addr != htonl(INADDR_ANY))
320 cmax = 1;
321
322 /* For simple GET or for root users,
323 * we try harder to allocate.
324 */
325 kp = (cmax <= 1 || capable(CAP_NET_ADMIN)) ?
326 kcalloc(cmax, sizeof(*kp), GFP_KERNEL_ACCOUNT | __GFP_NOWARN) :
327 NULL;
328
329 ca = min(t->prl_count, cmax);
330
331 if (!kp) {
332 /* We don't try hard to allocate much memory for
333 * non-root users.
334 * For root users, retry allocating enough memory for
335 * the answer.
336 */
337 kp = kcalloc(ca, sizeof(*kp), GFP_ATOMIC | __GFP_ACCOUNT |
338 __GFP_NOWARN);
339 if (!kp) {
340 ret = -ENOMEM;
341 goto out;
342 }
343 }
344
345 rcu_read_lock();
346 for_each_prl_rcu(t->prl) {
347 if (c >= cmax)
348 break;
349 if (kprl.addr != htonl(INADDR_ANY) && prl->addr != kprl.addr)
350 continue;
351 kp[c].addr = prl->addr;
352 kp[c].flags = prl->flags;
353 c++;
354 if (kprl.addr != htonl(INADDR_ANY))
355 break;
356 }
357
358 rcu_read_unlock();
359
360 len = sizeof(*kp) * c;
361 ret = 0;
362 if ((len && copy_to_user(to: a + 1, from: kp, n: len)) || put_user(len, &a->datalen))
363 ret = -EFAULT;
364
365 kfree(objp: kp);
366out:
367 return ret;
368}
369
370static int
371ipip6_tunnel_add_prl(struct ip_tunnel *t, struct ip_tunnel_prl *a, int chg)
372{
373 struct ip_tunnel_prl_entry *p;
374 int err = 0;
375
376 if (a->addr == htonl(INADDR_ANY))
377 return -EINVAL;
378
379 ASSERT_RTNL();
380
381 for (p = rtnl_dereference(t->prl); p; p = rtnl_dereference(p->next)) {
382 if (p->addr == a->addr) {
383 if (chg) {
384 p->flags = a->flags;
385 goto out;
386 }
387 err = -EEXIST;
388 goto out;
389 }
390 }
391
392 if (chg) {
393 err = -ENXIO;
394 goto out;
395 }
396
397 p = kzalloc(sizeof(struct ip_tunnel_prl_entry), GFP_KERNEL);
398 if (!p) {
399 err = -ENOBUFS;
400 goto out;
401 }
402
403 p->next = t->prl;
404 p->addr = a->addr;
405 p->flags = a->flags;
406 t->prl_count++;
407 rcu_assign_pointer(t->prl, p);
408out:
409 return err;
410}
411
412static void prl_list_destroy_rcu(struct rcu_head *head)
413{
414 struct ip_tunnel_prl_entry *p, *n;
415
416 p = container_of(head, struct ip_tunnel_prl_entry, rcu_head);
417 do {
418 n = rcu_dereference_protected(p->next, 1);
419 kfree(objp: p);
420 p = n;
421 } while (p);
422}
423
424static int
425ipip6_tunnel_del_prl(struct ip_tunnel *t, struct ip_tunnel_prl *a)
426{
427 struct ip_tunnel_prl_entry *x;
428 struct ip_tunnel_prl_entry __rcu **p;
429 int err = 0;
430
431 ASSERT_RTNL();
432
433 if (a && a->addr != htonl(INADDR_ANY)) {
434 for (p = &t->prl;
435 (x = rtnl_dereference(*p)) != NULL;
436 p = &x->next) {
437 if (x->addr == a->addr) {
438 *p = x->next;
439 kfree_rcu(x, rcu_head);
440 t->prl_count--;
441 goto out;
442 }
443 }
444 err = -ENXIO;
445 } else {
446 x = rtnl_dereference(t->prl);
447 if (x) {
448 t->prl_count = 0;
449 call_rcu(head: &x->rcu_head, func: prl_list_destroy_rcu);
450 t->prl = NULL;
451 }
452 }
453out:
454 return err;
455}
456
457static int ipip6_tunnel_prl_ctl(struct net_device *dev,
458 struct ip_tunnel_prl __user *data, int cmd)
459{
460 struct ip_tunnel *t = netdev_priv(dev);
461 struct ip_tunnel_prl prl;
462 int err;
463
464 if (!ns_capable(ns: t->net->user_ns, CAP_NET_ADMIN))
465 return -EPERM;
466 if (dev == dev_to_sit_net(dev)->fb_tunnel_dev)
467 return -EINVAL;
468
469 if (copy_from_user(to: &prl, from: data, n: sizeof(prl)))
470 return -EFAULT;
471
472 switch (cmd) {
473 case SIOCDELPRL:
474 err = ipip6_tunnel_del_prl(t, a: &prl);
475 break;
476 case SIOCADDPRL:
477 case SIOCCHGPRL:
478 err = ipip6_tunnel_add_prl(t, a: &prl, chg: cmd == SIOCCHGPRL);
479 break;
480 }
481 dst_cache_reset(dst_cache: &t->dst_cache);
482 netdev_state_change(dev);
483 return err;
484}
485
486static int
487isatap_chksrc(struct sk_buff *skb, const struct iphdr *iph, struct ip_tunnel *t)
488{
489 struct ip_tunnel_prl_entry *p;
490 int ok = 1;
491
492 rcu_read_lock();
493 p = __ipip6_tunnel_locate_prl(t, addr: iph->saddr);
494 if (p) {
495 if (p->flags & PRL_DEFAULT)
496 skb->ndisc_nodetype = NDISC_NODETYPE_DEFAULT;
497 else
498 skb->ndisc_nodetype = NDISC_NODETYPE_NODEFAULT;
499 } else {
500 const struct in6_addr *addr6 = &ipv6_hdr(skb)->saddr;
501
502 if (ipv6_addr_is_isatap(addr: addr6) &&
503 (addr6->s6_addr32[3] == iph->saddr) &&
504 ipv6_chk_prefix(addr: addr6, dev: t->dev))
505 skb->ndisc_nodetype = NDISC_NODETYPE_HOST;
506 else
507 ok = 0;
508 }
509 rcu_read_unlock();
510 return ok;
511}
512
513static void ipip6_tunnel_uninit(struct net_device *dev)
514{
515 struct ip_tunnel *tunnel = netdev_priv(dev);
516 struct sit_net *sitn = net_generic(net: tunnel->net, id: sit_net_id);
517
518 if (dev == sitn->fb_tunnel_dev) {
519 RCU_INIT_POINTER(sitn->tunnels_wc[0], NULL);
520 } else {
521 ipip6_tunnel_unlink(sitn, t: tunnel);
522 ipip6_tunnel_del_prl(t: tunnel, NULL);
523 }
524 dst_cache_reset(dst_cache: &tunnel->dst_cache);
525 netdev_put(dev, tracker: &tunnel->dev_tracker);
526}
527
528static int ipip6_err(struct sk_buff *skb, u32 info)
529{
530 const struct iphdr *iph = (const struct iphdr *)skb->data;
531 const int type = icmp_hdr(skb)->type;
532 const int code = icmp_hdr(skb)->code;
533 unsigned int data_len = 0;
534 struct ip_tunnel *t;
535 int sifindex;
536 int err;
537
538 switch (type) {
539 default:
540 case ICMP_PARAMETERPROB:
541 return 0;
542
543 case ICMP_DEST_UNREACH:
544 switch (code) {
545 case ICMP_SR_FAILED:
546 /* Impossible event. */
547 return 0;
548 default:
549 /* All others are translated to HOST_UNREACH.
550 rfc2003 contains "deep thoughts" about NET_UNREACH,
551 I believe they are just ether pollution. --ANK
552 */
553 break;
554 }
555 break;
556 case ICMP_TIME_EXCEEDED:
557 if (code != ICMP_EXC_TTL)
558 return 0;
559 data_len = icmp_hdr(skb)->un.reserved[1] * 4; /* RFC 4884 4.1 */
560 break;
561 case ICMP_REDIRECT:
562 break;
563 }
564
565 err = -ENOENT;
566
567 sifindex = netif_is_l3_master(dev: skb->dev) ? IPCB(skb)->iif : 0;
568 t = ipip6_tunnel_lookup(net: dev_net(dev: skb->dev), dev: skb->dev,
569 remote: iph->daddr, local: iph->saddr, sifindex);
570 if (!t)
571 goto out;
572
573 if (type == ICMP_DEST_UNREACH && code == ICMP_FRAG_NEEDED) {
574 ipv4_update_pmtu(skb, net: dev_net(dev: skb->dev), mtu: info,
575 oif: t->parms.link, protocol: iph->protocol);
576 err = 0;
577 goto out;
578 }
579 if (type == ICMP_REDIRECT) {
580 ipv4_redirect(skb, net: dev_net(dev: skb->dev), oif: t->parms.link,
581 protocol: iph->protocol);
582 err = 0;
583 goto out;
584 }
585
586 err = 0;
587 if (__in6_dev_get(dev: skb->dev) &&
588 !ip6_err_gen_icmpv6_unreach(skb, nhs: iph->ihl * 4, type, data_len))
589 goto out;
590
591 if (t->parms.iph.daddr == 0)
592 goto out;
593
594 if (t->parms.iph.ttl == 0 && type == ICMP_TIME_EXCEEDED)
595 goto out;
596
597 if (time_before(jiffies, t->err_time + IPTUNNEL_ERR_TIMEO))
598 t->err_count++;
599 else
600 t->err_count = 1;
601 t->err_time = jiffies;
602out:
603 return err;
604}
605
606static inline bool is_spoofed_6rd(struct ip_tunnel *tunnel, const __be32 v4addr,
607 const struct in6_addr *v6addr)
608{
609 __be32 v4embed = 0;
610 if (check_6rd(tunnel, v6dst: v6addr, v4dst: &v4embed) && v4addr != v4embed)
611 return true;
612 return false;
613}
614
615/* Checks if an address matches an address on the tunnel interface.
616 * Used to detect the NAT of proto 41 packets and let them pass spoofing test.
617 * Long story:
618 * This function is called after we considered the packet as spoofed
619 * in is_spoofed_6rd.
620 * We may have a router that is doing NAT for proto 41 packets
621 * for an internal station. Destination a.a.a.a/PREFIX:bbbb:bbbb
622 * will be translated to n.n.n.n/PREFIX:bbbb:bbbb. And is_spoofed_6rd
623 * function will return true, dropping the packet.
624 * But, we can still check if is spoofed against the IP
625 * addresses associated with the interface.
626 */
627static bool only_dnatted(const struct ip_tunnel *tunnel,
628 const struct in6_addr *v6dst)
629{
630 int prefix_len;
631
632#ifdef CONFIG_IPV6_SIT_6RD
633 prefix_len = tunnel->ip6rd.prefixlen + 32
634 - tunnel->ip6rd.relay_prefixlen;
635#else
636 prefix_len = 48;
637#endif
638 return ipv6_chk_custom_prefix(addr: v6dst, prefix_len, dev: tunnel->dev);
639}
640
641/* Returns true if a packet is spoofed */
642static bool packet_is_spoofed(struct sk_buff *skb,
643 const struct iphdr *iph,
644 struct ip_tunnel *tunnel)
645{
646 const struct ipv6hdr *ipv6h;
647
648 if (tunnel->dev->priv_flags & IFF_ISATAP) {
649 if (!isatap_chksrc(skb, iph, t: tunnel))
650 return true;
651
652 return false;
653 }
654
655 if (tunnel->dev->flags & IFF_POINTOPOINT)
656 return false;
657
658 ipv6h = ipv6_hdr(skb);
659
660 if (unlikely(is_spoofed_6rd(tunnel, iph->saddr, &ipv6h->saddr))) {
661 net_warn_ratelimited("Src spoofed %pI4/%pI6c -> %pI4/%pI6c\n",
662 &iph->saddr, &ipv6h->saddr,
663 &iph->daddr, &ipv6h->daddr);
664 return true;
665 }
666
667 if (likely(!is_spoofed_6rd(tunnel, iph->daddr, &ipv6h->daddr)))
668 return false;
669
670 if (only_dnatted(tunnel, v6dst: &ipv6h->daddr))
671 return false;
672
673 net_warn_ratelimited("Dst spoofed %pI4/%pI6c -> %pI4/%pI6c\n",
674 &iph->saddr, &ipv6h->saddr,
675 &iph->daddr, &ipv6h->daddr);
676 return true;
677}
678
679static int ipip6_rcv(struct sk_buff *skb)
680{
681 const struct iphdr *iph = ip_hdr(skb);
682 struct ip_tunnel *tunnel;
683 int sifindex;
684 int err;
685
686 sifindex = netif_is_l3_master(dev: skb->dev) ? IPCB(skb)->iif : 0;
687 tunnel = ipip6_tunnel_lookup(net: dev_net(dev: skb->dev), dev: skb->dev,
688 remote: iph->saddr, local: iph->daddr, sifindex);
689 if (tunnel) {
690 if (tunnel->parms.iph.protocol != IPPROTO_IPV6 &&
691 tunnel->parms.iph.protocol != 0)
692 goto out;
693
694 skb->mac_header = skb->network_header;
695 skb_reset_network_header(skb);
696 IPCB(skb)->flags = 0;
697 skb->dev = tunnel->dev;
698
699 if (packet_is_spoofed(skb, iph, tunnel)) {
700 DEV_STATS_INC(tunnel->dev, rx_errors);
701 goto out;
702 }
703
704 if (iptunnel_pull_header(skb, hdr_len: 0, htons(ETH_P_IPV6),
705 xnet: !net_eq(net1: tunnel->net, net2: dev_net(dev: tunnel->dev))))
706 goto out;
707
708 /* skb can be uncloned in iptunnel_pull_header, so
709 * old iph is no longer valid
710 */
711 iph = (const struct iphdr *)skb_mac_header(skb);
712 skb_reset_mac_header(skb);
713
714 err = IP_ECN_decapsulate(oiph: iph, skb);
715 if (unlikely(err)) {
716 if (log_ecn_error)
717 net_info_ratelimited("non-ECT from %pI4 with TOS=%#x\n",
718 &iph->saddr, iph->tos);
719 if (err > 1) {
720 DEV_STATS_INC(tunnel->dev, rx_frame_errors);
721 DEV_STATS_INC(tunnel->dev, rx_errors);
722 goto out;
723 }
724 }
725
726 dev_sw_netstats_rx_add(dev: tunnel->dev, len: skb->len);
727
728 netif_rx(skb);
729
730 return 0;
731 }
732
733 /* no tunnel matched, let upstream know, ipsec may handle it */
734 return 1;
735out:
736 kfree_skb(skb);
737 return 0;
738}
739
740static const struct tnl_ptk_info ipip_tpi = {
741 /* no tunnel info required for ipip. */
742 .proto = htons(ETH_P_IP),
743};
744
745#if IS_ENABLED(CONFIG_MPLS)
746static const struct tnl_ptk_info mplsip_tpi = {
747 /* no tunnel info required for mplsip. */
748 .proto = htons(ETH_P_MPLS_UC),
749};
750#endif
751
752static int sit_tunnel_rcv(struct sk_buff *skb, u8 ipproto)
753{
754 const struct iphdr *iph;
755 struct ip_tunnel *tunnel;
756 int sifindex;
757
758 sifindex = netif_is_l3_master(dev: skb->dev) ? IPCB(skb)->iif : 0;
759
760 iph = ip_hdr(skb);
761 tunnel = ipip6_tunnel_lookup(net: dev_net(dev: skb->dev), dev: skb->dev,
762 remote: iph->saddr, local: iph->daddr, sifindex);
763 if (tunnel) {
764 const struct tnl_ptk_info *tpi;
765
766 if (tunnel->parms.iph.protocol != ipproto &&
767 tunnel->parms.iph.protocol != 0)
768 goto drop;
769
770 if (!xfrm4_policy_check(NULL, dir: XFRM_POLICY_IN, skb))
771 goto drop;
772#if IS_ENABLED(CONFIG_MPLS)
773 if (ipproto == IPPROTO_MPLS)
774 tpi = &mplsip_tpi;
775 else
776#endif
777 tpi = &ipip_tpi;
778 if (iptunnel_pull_header(skb, hdr_len: 0, inner_proto: tpi->proto, xnet: false))
779 goto drop;
780 skb_reset_mac_header(skb);
781
782 return ip_tunnel_rcv(tunnel, skb, tpi, NULL, log_ecn_error);
783 }
784
785 return 1;
786
787drop:
788 kfree_skb(skb);
789 return 0;
790}
791
792static int ipip_rcv(struct sk_buff *skb)
793{
794 return sit_tunnel_rcv(skb, IPPROTO_IPIP);
795}
796
797#if IS_ENABLED(CONFIG_MPLS)
798static int mplsip_rcv(struct sk_buff *skb)
799{
800 return sit_tunnel_rcv(skb, IPPROTO_MPLS);
801}
802#endif
803
804/*
805 * If the IPv6 address comes from 6rd / 6to4 (RFC 3056) addr space this function
806 * stores the embedded IPv4 address in v4dst and returns true.
807 */
808static bool check_6rd(struct ip_tunnel *tunnel, const struct in6_addr *v6dst,
809 __be32 *v4dst)
810{
811#ifdef CONFIG_IPV6_SIT_6RD
812 if (ipv6_prefix_equal(v6dst, &tunnel->ip6rd.prefix,
813 tunnel->ip6rd.prefixlen)) {
814 unsigned int pbw0, pbi0;
815 int pbi1;
816 u32 d;
817
818 pbw0 = tunnel->ip6rd.prefixlen >> 5;
819 pbi0 = tunnel->ip6rd.prefixlen & 0x1f;
820
821 d = tunnel->ip6rd.relay_prefixlen < 32 ?
822 (ntohl(v6dst->s6_addr32[pbw0]) << pbi0) >>
823 tunnel->ip6rd.relay_prefixlen : 0;
824
825 pbi1 = pbi0 - tunnel->ip6rd.relay_prefixlen;
826 if (pbi1 > 0)
827 d |= ntohl(v6dst->s6_addr32[pbw0 + 1]) >>
828 (32 - pbi1);
829
830 *v4dst = tunnel->ip6rd.relay_prefix | htonl(d);
831 return true;
832 }
833#else
834 if (v6dst->s6_addr16[0] == htons(0x2002)) {
835 /* 6to4 v6 addr has 16 bits prefix, 32 v4addr, 16 SLA, ... */
836 memcpy(to: v4dst, from: &v6dst->s6_addr16[1], len: 4);
837 return true;
838 }
839#endif
840 return false;
841}
842
843static inline __be32 try_6rd(struct ip_tunnel *tunnel,
844 const struct in6_addr *v6dst)
845{
846 __be32 dst = 0;
847 check_6rd(tunnel, v6dst, v4dst: &dst);
848 return dst;
849}
850
851static bool ipip6_tunnel_dst_find(struct sk_buff *skb, __be32 *dst,
852 bool is_isatap)
853{
854 const struct ipv6hdr *iph6 = ipv6_hdr(skb);
855 struct neighbour *neigh = NULL;
856 const struct in6_addr *addr6;
857 bool found = false;
858 int addr_type;
859
860 if (skb_dst(skb))
861 neigh = dst_neigh_lookup(dst: skb_dst(skb), daddr: &iph6->daddr);
862
863 if (!neigh) {
864 net_dbg_ratelimited("nexthop == NULL\n");
865 return false;
866 }
867
868 addr6 = (const struct in6_addr *)&neigh->primary_key;
869 addr_type = ipv6_addr_type(addr: addr6);
870
871 if (is_isatap) {
872 if ((addr_type & IPV6_ADDR_UNICAST) &&
873 ipv6_addr_is_isatap(addr: addr6)) {
874 *dst = addr6->s6_addr32[3];
875 found = true;
876 }
877 } else {
878 if (addr_type == IPV6_ADDR_ANY) {
879 addr6 = &ipv6_hdr(skb)->daddr;
880 addr_type = ipv6_addr_type(addr: addr6);
881 }
882
883 if ((addr_type & IPV6_ADDR_COMPATv4) != 0) {
884 *dst = addr6->s6_addr32[3];
885 found = true;
886 }
887 }
888
889 neigh_release(neigh);
890
891 return found;
892}
893
894/*
895 * This function assumes it is being called from dev_queue_xmit()
896 * and that skb is filled properly by that function.
897 */
898
899static netdev_tx_t ipip6_tunnel_xmit(struct sk_buff *skb,
900 struct net_device *dev)
901{
902 struct ip_tunnel *tunnel = netdev_priv(dev);
903 const struct iphdr *tiph = &tunnel->parms.iph;
904 const struct ipv6hdr *iph6 = ipv6_hdr(skb);
905 u8 tos = tunnel->parms.iph.tos;
906 __be16 df = tiph->frag_off;
907 struct rtable *rt; /* Route to the other host */
908 struct net_device *tdev; /* Device to other host */
909 unsigned int max_headroom; /* The extra header space needed */
910 __be32 dst = tiph->daddr;
911 struct flowi4 fl4;
912 int mtu;
913 u8 ttl;
914 u8 protocol = IPPROTO_IPV6;
915 int t_hlen = tunnel->hlen + sizeof(struct iphdr);
916
917 if (tos == 1)
918 tos = ipv6_get_dsfield(ipv6h: iph6);
919
920 /* ISATAP (RFC4214) - must come before 6to4 */
921 if ((dev->priv_flags & IFF_ISATAP) &&
922 !ipip6_tunnel_dst_find(skb, dst: &dst, is_isatap: true))
923 goto tx_error;
924
925 if (!dst)
926 dst = try_6rd(tunnel, v6dst: &iph6->daddr);
927
928 if (!dst && !ipip6_tunnel_dst_find(skb, dst: &dst, is_isatap: false))
929 goto tx_error;
930
931 flowi4_init_output(fl4: &fl4, oif: tunnel->parms.link, mark: tunnel->fwmark,
932 tos: tos & INET_DSCP_MASK, scope: RT_SCOPE_UNIVERSE,
933 IPPROTO_IPV6, flags: 0, daddr: dst, saddr: tiph->saddr, dport: 0, sport: 0,
934 uid: sock_net_uid(net: tunnel->net, NULL));
935
936 rt = dst_cache_get_ip4(dst_cache: &tunnel->dst_cache, saddr: &fl4.saddr);
937 if (!rt) {
938 rt = ip_route_output_flow(tunnel->net, flp: &fl4, NULL);
939 if (IS_ERR(ptr: rt)) {
940 DEV_STATS_INC(dev, tx_carrier_errors);
941 goto tx_error_icmp;
942 }
943 dst_cache_set_ip4(dst_cache: &tunnel->dst_cache, dst: &rt->dst, saddr: fl4.saddr);
944 }
945
946 if (rt->rt_type != RTN_UNICAST && rt->rt_type != RTN_LOCAL) {
947 ip_rt_put(rt);
948 DEV_STATS_INC(dev, tx_carrier_errors);
949 goto tx_error_icmp;
950 }
951 tdev = rt->dst.dev;
952
953 if (tdev == dev) {
954 ip_rt_put(rt);
955 DEV_STATS_INC(dev, collisions);
956 goto tx_error;
957 }
958
959 if (iptunnel_handle_offloads(skb, gso_type_mask: SKB_GSO_IPXIP4)) {
960 ip_rt_put(rt);
961 goto tx_error;
962 }
963
964 if (df) {
965 mtu = dst_mtu(dst: &rt->dst) - t_hlen;
966
967 if (mtu < IPV4_MIN_MTU) {
968 DEV_STATS_INC(dev, collisions);
969 ip_rt_put(rt);
970 goto tx_error;
971 }
972
973 if (mtu < IPV6_MIN_MTU) {
974 mtu = IPV6_MIN_MTU;
975 df = 0;
976 }
977
978 if (tunnel->parms.iph.daddr)
979 skb_dst_update_pmtu_no_confirm(skb, mtu);
980
981 if (skb->len > mtu && !skb_is_gso(skb)) {
982 icmpv6_ndo_send(skb_in: skb, ICMPV6_PKT_TOOBIG, code: 0, info: mtu);
983 ip_rt_put(rt);
984 goto tx_error;
985 }
986 }
987
988 if (tunnel->err_count > 0) {
989 if (time_before(jiffies,
990 tunnel->err_time + IPTUNNEL_ERR_TIMEO)) {
991 tunnel->err_count--;
992 dst_link_failure(skb);
993 } else
994 tunnel->err_count = 0;
995 }
996
997 /*
998 * Okay, now see if we can stuff it in the buffer as-is.
999 */
1000 max_headroom = LL_RESERVED_SPACE(tdev) + t_hlen;
1001
1002 if (skb_headroom(skb) < max_headroom || skb_shared(skb) ||
1003 (skb_cloned(skb) && !skb_clone_writable(skb, len: 0))) {
1004 struct sk_buff *new_skb = skb_realloc_headroom(skb, headroom: max_headroom);
1005 if (!new_skb) {
1006 ip_rt_put(rt);
1007 DEV_STATS_INC(dev, tx_dropped);
1008 kfree_skb(skb);
1009 return NETDEV_TX_OK;
1010 }
1011 if (skb->sk)
1012 skb_set_owner_w(skb: new_skb, sk: skb->sk);
1013 dev_kfree_skb(skb);
1014 skb = new_skb;
1015 iph6 = ipv6_hdr(skb);
1016 }
1017 ttl = tiph->ttl;
1018 if (ttl == 0)
1019 ttl = iph6->hop_limit;
1020 tos = INET_ECN_encapsulate(outer: tos, inner: ipv6_get_dsfield(ipv6h: iph6));
1021
1022 if (ip_tunnel_encap(skb, e: &tunnel->encap, protocol: &protocol, fl4: &fl4) < 0) {
1023 ip_rt_put(rt);
1024 goto tx_error;
1025 }
1026
1027 skb_set_inner_ipproto(skb, IPPROTO_IPV6);
1028
1029 iptunnel_xmit(NULL, rt, skb, src: fl4.saddr, dst: fl4.daddr, proto: protocol, tos, ttl,
1030 df, xnet: !net_eq(net1: tunnel->net, net2: dev_net(dev)), ipcb_flags: 0);
1031 return NETDEV_TX_OK;
1032
1033tx_error_icmp:
1034 dst_link_failure(skb);
1035tx_error:
1036 kfree_skb(skb);
1037 DEV_STATS_INC(dev, tx_errors);
1038 return NETDEV_TX_OK;
1039}
1040
1041static netdev_tx_t sit_tunnel_xmit__(struct sk_buff *skb,
1042 struct net_device *dev, u8 ipproto)
1043{
1044 struct ip_tunnel *tunnel = netdev_priv(dev);
1045 const struct iphdr *tiph = &tunnel->parms.iph;
1046
1047 if (iptunnel_handle_offloads(skb, gso_type_mask: SKB_GSO_IPXIP4))
1048 goto tx_error;
1049
1050 skb_set_inner_ipproto(skb, ipproto);
1051
1052 ip_tunnel_xmit(skb, dev, tnl_params: tiph, protocol: ipproto);
1053 return NETDEV_TX_OK;
1054tx_error:
1055 kfree_skb(skb);
1056 DEV_STATS_INC(dev, tx_errors);
1057 return NETDEV_TX_OK;
1058}
1059
1060static netdev_tx_t sit_tunnel_xmit(struct sk_buff *skb,
1061 struct net_device *dev)
1062{
1063 if (!pskb_inet_may_pull(skb))
1064 goto tx_err;
1065
1066 switch (skb->protocol) {
1067 case htons(ETH_P_IP):
1068 sit_tunnel_xmit__(skb, dev, IPPROTO_IPIP);
1069 break;
1070 case htons(ETH_P_IPV6):
1071 ipip6_tunnel_xmit(skb, dev);
1072 break;
1073#if IS_ENABLED(CONFIG_MPLS)
1074 case htons(ETH_P_MPLS_UC):
1075 sit_tunnel_xmit__(skb, dev, IPPROTO_MPLS);
1076 break;
1077#endif
1078 default:
1079 goto tx_err;
1080 }
1081
1082 return NETDEV_TX_OK;
1083
1084tx_err:
1085 DEV_STATS_INC(dev, tx_errors);
1086 kfree_skb(skb);
1087 return NETDEV_TX_OK;
1088
1089}
1090
1091static void ipip6_tunnel_bind_dev(struct net_device *dev)
1092{
1093 struct ip_tunnel *tunnel = netdev_priv(dev);
1094 int t_hlen = tunnel->hlen + sizeof(struct iphdr);
1095 struct net_device *tdev = NULL;
1096 int hlen = LL_MAX_HEADER;
1097 const struct iphdr *iph;
1098 struct flowi4 fl4;
1099
1100 iph = &tunnel->parms.iph;
1101
1102 if (iph->daddr) {
1103 struct rtable *rt = ip_route_output_ports(net: tunnel->net, fl4: &fl4,
1104 NULL,
1105 daddr: iph->daddr, saddr: iph->saddr,
1106 dport: 0, sport: 0,
1107 IPPROTO_IPV6,
1108 tos: iph->tos & INET_DSCP_MASK,
1109 oif: tunnel->parms.link);
1110
1111 if (!IS_ERR(ptr: rt)) {
1112 tdev = rt->dst.dev;
1113 ip_rt_put(rt);
1114 }
1115 dev->flags |= IFF_POINTOPOINT;
1116 }
1117
1118 if (!tdev && tunnel->parms.link)
1119 tdev = __dev_get_by_index(net: tunnel->net, ifindex: tunnel->parms.link);
1120
1121 if (tdev && !netif_is_l3_master(dev: tdev)) {
1122 int mtu;
1123
1124 mtu = tdev->mtu - t_hlen;
1125 if (mtu < IPV6_MIN_MTU)
1126 mtu = IPV6_MIN_MTU;
1127 WRITE_ONCE(dev->mtu, mtu);
1128 hlen = tdev->hard_header_len + tdev->needed_headroom;
1129 }
1130 dev->needed_headroom = t_hlen + hlen;
1131}
1132
1133static void ipip6_tunnel_update(struct ip_tunnel *t,
1134 struct ip_tunnel_parm_kern *p,
1135 __u32 fwmark)
1136{
1137 struct net *net = t->net;
1138 struct sit_net *sitn = net_generic(net, id: sit_net_id);
1139
1140 ipip6_tunnel_unlink(sitn, t);
1141 synchronize_net();
1142 t->parms.iph.saddr = p->iph.saddr;
1143 t->parms.iph.daddr = p->iph.daddr;
1144 __dev_addr_set(dev: t->dev, addr: &p->iph.saddr, len: 4);
1145 memcpy(to: t->dev->broadcast, from: &p->iph.daddr, len: 4);
1146 ipip6_tunnel_link(sitn, t);
1147 t->parms.iph.ttl = p->iph.ttl;
1148 t->parms.iph.tos = p->iph.tos;
1149 t->parms.iph.frag_off = p->iph.frag_off;
1150 if (t->parms.link != p->link || t->fwmark != fwmark) {
1151 t->parms.link = p->link;
1152 t->fwmark = fwmark;
1153 ipip6_tunnel_bind_dev(dev: t->dev);
1154 }
1155 dst_cache_reset(dst_cache: &t->dst_cache);
1156 netdev_state_change(dev: t->dev);
1157}
1158
1159#ifdef CONFIG_IPV6_SIT_6RD
1160static int ipip6_tunnel_update_6rd(struct ip_tunnel *t,
1161 struct ip_tunnel_6rd *ip6rd)
1162{
1163 struct in6_addr prefix;
1164 __be32 relay_prefix;
1165
1166 if (ip6rd->relay_prefixlen > 32 ||
1167 ip6rd->prefixlen + (32 - ip6rd->relay_prefixlen) > 64)
1168 return -EINVAL;
1169
1170 ipv6_addr_prefix(&prefix, &ip6rd->prefix, ip6rd->prefixlen);
1171 if (!ipv6_addr_equal(&prefix, &ip6rd->prefix))
1172 return -EINVAL;
1173 if (ip6rd->relay_prefixlen)
1174 relay_prefix = ip6rd->relay_prefix &
1175 htonl(0xffffffffUL <<
1176 (32 - ip6rd->relay_prefixlen));
1177 else
1178 relay_prefix = 0;
1179 if (relay_prefix != ip6rd->relay_prefix)
1180 return -EINVAL;
1181
1182 t->ip6rd.prefix = prefix;
1183 t->ip6rd.relay_prefix = relay_prefix;
1184 t->ip6rd.prefixlen = ip6rd->prefixlen;
1185 t->ip6rd.relay_prefixlen = ip6rd->relay_prefixlen;
1186 dst_cache_reset(&t->dst_cache);
1187 netdev_state_change(t->dev);
1188 return 0;
1189}
1190
1191static int
1192ipip6_tunnel_get6rd(struct net_device *dev, struct ip_tunnel_parm __user *data)
1193{
1194 struct ip_tunnel *t = netdev_priv(dev);
1195 struct ip_tunnel_parm_kern p;
1196 struct ip_tunnel_6rd ip6rd;
1197
1198 if (dev == dev_to_sit_net(dev)->fb_tunnel_dev) {
1199 if (!ip_tunnel_parm_from_user(&p, data))
1200 return -EFAULT;
1201 t = ipip6_tunnel_locate(t->net, &p, 0);
1202 }
1203 if (!t)
1204 t = netdev_priv(dev);
1205
1206 ip6rd.prefix = t->ip6rd.prefix;
1207 ip6rd.relay_prefix = t->ip6rd.relay_prefix;
1208 ip6rd.prefixlen = t->ip6rd.prefixlen;
1209 ip6rd.relay_prefixlen = t->ip6rd.relay_prefixlen;
1210 if (copy_to_user(data, &ip6rd, sizeof(ip6rd)))
1211 return -EFAULT;
1212 return 0;
1213}
1214
1215static int
1216ipip6_tunnel_6rdctl(struct net_device *dev, struct ip_tunnel_6rd __user *data,
1217 int cmd)
1218{
1219 struct ip_tunnel *t = netdev_priv(dev);
1220 struct ip_tunnel_6rd ip6rd;
1221 int err;
1222
1223 if (!ns_capable(t->net->user_ns, CAP_NET_ADMIN))
1224 return -EPERM;
1225 if (copy_from_user(&ip6rd, data, sizeof(ip6rd)))
1226 return -EFAULT;
1227
1228 if (cmd != SIOCDEL6RD) {
1229 err = ipip6_tunnel_update_6rd(t, &ip6rd);
1230 if (err < 0)
1231 return err;
1232 } else
1233 ipip6_tunnel_clone_6rd(dev, dev_to_sit_net(dev));
1234 return 0;
1235}
1236
1237#endif /* CONFIG_IPV6_SIT_6RD */
1238
1239static bool ipip6_valid_ip_proto(u8 ipproto)
1240{
1241 return ipproto == IPPROTO_IPV6 ||
1242 ipproto == IPPROTO_IPIP ||
1243#if IS_ENABLED(CONFIG_MPLS)
1244 ipproto == IPPROTO_MPLS ||
1245#endif
1246 ipproto == 0;
1247}
1248
1249static int
1250__ipip6_tunnel_ioctl_validate(struct net *net, struct ip_tunnel_parm_kern *p)
1251{
1252 if (!ns_capable(ns: net->user_ns, CAP_NET_ADMIN))
1253 return -EPERM;
1254
1255 if (!ipip6_valid_ip_proto(ipproto: p->iph.protocol))
1256 return -EINVAL;
1257 if (p->iph.version != 4 ||
1258 p->iph.ihl != 5 || (p->iph.frag_off & htons(~IP_DF)))
1259 return -EINVAL;
1260
1261 if (p->iph.ttl)
1262 p->iph.frag_off |= htons(IP_DF);
1263 return 0;
1264}
1265
1266static int
1267ipip6_tunnel_get(struct net_device *dev, struct ip_tunnel_parm_kern *p)
1268{
1269 struct ip_tunnel *t = netdev_priv(dev);
1270
1271 if (dev == dev_to_sit_net(dev)->fb_tunnel_dev)
1272 t = ipip6_tunnel_locate(net: t->net, parms: p, create: 0);
1273 if (!t)
1274 t = netdev_priv(dev);
1275 memcpy(to: p, from: &t->parms, len: sizeof(*p));
1276 return 0;
1277}
1278
1279static int
1280ipip6_tunnel_add(struct net_device *dev, struct ip_tunnel_parm_kern *p)
1281{
1282 struct ip_tunnel *t = netdev_priv(dev);
1283 int err;
1284
1285 err = __ipip6_tunnel_ioctl_validate(net: t->net, p);
1286 if (err)
1287 return err;
1288
1289 t = ipip6_tunnel_locate(net: t->net, parms: p, create: 1);
1290 if (!t)
1291 return -ENOBUFS;
1292 return 0;
1293}
1294
1295static int
1296ipip6_tunnel_change(struct net_device *dev, struct ip_tunnel_parm_kern *p)
1297{
1298 struct ip_tunnel *t = netdev_priv(dev);
1299 int err;
1300
1301 err = __ipip6_tunnel_ioctl_validate(net: t->net, p);
1302 if (err)
1303 return err;
1304
1305 t = ipip6_tunnel_locate(net: t->net, parms: p, create: 0);
1306 if (dev == dev_to_sit_net(dev)->fb_tunnel_dev) {
1307 if (!t)
1308 return -ENOENT;
1309 } else {
1310 if (t) {
1311 if (t->dev != dev)
1312 return -EEXIST;
1313 } else {
1314 if (((dev->flags & IFF_POINTOPOINT) && !p->iph.daddr) ||
1315 (!(dev->flags & IFF_POINTOPOINT) && p->iph.daddr))
1316 return -EINVAL;
1317 t = netdev_priv(dev);
1318 }
1319
1320 ipip6_tunnel_update(t, p, fwmark: t->fwmark);
1321 }
1322
1323 return 0;
1324}
1325
1326static int
1327ipip6_tunnel_del(struct net_device *dev, struct ip_tunnel_parm_kern *p)
1328{
1329 struct ip_tunnel *t = netdev_priv(dev);
1330
1331 if (!ns_capable(ns: t->net->user_ns, CAP_NET_ADMIN))
1332 return -EPERM;
1333
1334 if (dev == dev_to_sit_net(dev)->fb_tunnel_dev) {
1335 t = ipip6_tunnel_locate(net: t->net, parms: p, create: 0);
1336 if (!t)
1337 return -ENOENT;
1338 if (t == netdev_priv(dev: dev_to_sit_net(dev)->fb_tunnel_dev))
1339 return -EPERM;
1340 dev = t->dev;
1341 }
1342 unregister_netdevice(dev);
1343 return 0;
1344}
1345
1346static int
1347ipip6_tunnel_ctl(struct net_device *dev, struct ip_tunnel_parm_kern *p,
1348 int cmd)
1349{
1350 switch (cmd) {
1351 case SIOCGETTUNNEL:
1352 return ipip6_tunnel_get(dev, p);
1353 case SIOCADDTUNNEL:
1354 return ipip6_tunnel_add(dev, p);
1355 case SIOCCHGTUNNEL:
1356 return ipip6_tunnel_change(dev, p);
1357 case SIOCDELTUNNEL:
1358 return ipip6_tunnel_del(dev, p);
1359 default:
1360 return -EINVAL;
1361 }
1362}
1363
1364static int
1365ipip6_tunnel_siocdevprivate(struct net_device *dev, struct ifreq *ifr,
1366 void __user *data, int cmd)
1367{
1368 switch (cmd) {
1369 case SIOCGETTUNNEL:
1370 case SIOCADDTUNNEL:
1371 case SIOCCHGTUNNEL:
1372 case SIOCDELTUNNEL:
1373 return ip_tunnel_siocdevprivate(dev, ifr, data, cmd);
1374 case SIOCGETPRL:
1375 return ipip6_tunnel_get_prl(dev, a: data);
1376 case SIOCADDPRL:
1377 case SIOCDELPRL:
1378 case SIOCCHGPRL:
1379 return ipip6_tunnel_prl_ctl(dev, data, cmd);
1380#ifdef CONFIG_IPV6_SIT_6RD
1381 case SIOCGET6RD:
1382 return ipip6_tunnel_get6rd(dev, data);
1383 case SIOCADD6RD:
1384 case SIOCCHG6RD:
1385 case SIOCDEL6RD:
1386 return ipip6_tunnel_6rdctl(dev, data, cmd);
1387#endif
1388 default:
1389 return -EINVAL;
1390 }
1391}
1392
1393static const struct net_device_ops ipip6_netdev_ops = {
1394 .ndo_init = ipip6_tunnel_init,
1395 .ndo_uninit = ipip6_tunnel_uninit,
1396 .ndo_start_xmit = sit_tunnel_xmit,
1397 .ndo_siocdevprivate = ipip6_tunnel_siocdevprivate,
1398 .ndo_get_iflink = ip_tunnel_get_iflink,
1399 .ndo_tunnel_ctl = ipip6_tunnel_ctl,
1400};
1401
1402static void ipip6_dev_free(struct net_device *dev)
1403{
1404 struct ip_tunnel *tunnel = netdev_priv(dev);
1405
1406 dst_cache_destroy(dst_cache: &tunnel->dst_cache);
1407}
1408
1409#define SIT_FEATURES (NETIF_F_SG | \
1410 NETIF_F_FRAGLIST | \
1411 NETIF_F_HIGHDMA | \
1412 NETIF_F_GSO_SOFTWARE | \
1413 NETIF_F_HW_CSUM)
1414
1415static void ipip6_tunnel_setup(struct net_device *dev)
1416{
1417 struct ip_tunnel *tunnel = netdev_priv(dev);
1418 int t_hlen = tunnel->hlen + sizeof(struct iphdr);
1419
1420 dev->netdev_ops = &ipip6_netdev_ops;
1421 dev->header_ops = &ip_tunnel_header_ops;
1422 dev->needs_free_netdev = true;
1423 dev->priv_destructor = ipip6_dev_free;
1424
1425 dev->type = ARPHRD_SIT;
1426 dev->mtu = ETH_DATA_LEN - t_hlen;
1427 dev->min_mtu = IPV6_MIN_MTU;
1428 dev->max_mtu = IP6_MAX_MTU - t_hlen;
1429 dev->flags = IFF_NOARP;
1430 netif_keep_dst(dev);
1431 dev->addr_len = 4;
1432 dev->lltx = true;
1433 dev->features |= SIT_FEATURES;
1434 dev->hw_features |= SIT_FEATURES;
1435 dev->pcpu_stat_type = NETDEV_PCPU_STAT_TSTATS;
1436
1437}
1438
1439static int ipip6_tunnel_init(struct net_device *dev)
1440{
1441 struct ip_tunnel *tunnel = netdev_priv(dev);
1442 int err;
1443
1444 tunnel->dev = dev;
1445 strcpy(tunnel->parms.name, dev->name);
1446
1447 ipip6_tunnel_bind_dev(dev);
1448
1449 err = dst_cache_init(dst_cache: &tunnel->dst_cache, GFP_KERNEL);
1450 if (err)
1451 return err;
1452
1453 netdev_hold(dev, tracker: &tunnel->dev_tracker, GFP_KERNEL);
1454 netdev_lockdep_set_classes(dev);
1455 return 0;
1456}
1457
1458static void __net_init ipip6_fb_tunnel_init(struct net_device *dev)
1459{
1460 struct ip_tunnel *tunnel = netdev_priv(dev);
1461 struct iphdr *iph = &tunnel->parms.iph;
1462 struct net *net = dev_net(dev);
1463 struct sit_net *sitn = net_generic(net, id: sit_net_id);
1464
1465 iph->version = 4;
1466 iph->protocol = IPPROTO_IPV6;
1467 iph->ihl = 5;
1468 iph->ttl = 64;
1469
1470 rcu_assign_pointer(sitn->tunnels_wc[0], tunnel);
1471}
1472
1473static int ipip6_validate(struct nlattr *tb[], struct nlattr *data[],
1474 struct netlink_ext_ack *extack)
1475{
1476 u8 proto;
1477
1478 if (!data || !data[IFLA_IPTUN_PROTO])
1479 return 0;
1480
1481 proto = nla_get_u8(nla: data[IFLA_IPTUN_PROTO]);
1482 if (!ipip6_valid_ip_proto(ipproto: proto))
1483 return -EINVAL;
1484
1485 return 0;
1486}
1487
1488static void ipip6_netlink_parms(struct nlattr *data[],
1489 struct ip_tunnel_parm_kern *parms,
1490 __u32 *fwmark)
1491{
1492 memset(s: parms, c: 0, n: sizeof(*parms));
1493
1494 parms->iph.version = 4;
1495 parms->iph.protocol = IPPROTO_IPV6;
1496 parms->iph.ihl = 5;
1497 parms->iph.ttl = 64;
1498
1499 if (!data)
1500 return;
1501
1502 ip_tunnel_netlink_parms(data, parms);
1503
1504 if (data[IFLA_IPTUN_FWMARK])
1505 *fwmark = nla_get_u32(nla: data[IFLA_IPTUN_FWMARK]);
1506}
1507
1508#ifdef CONFIG_IPV6_SIT_6RD
1509/* This function returns true when 6RD attributes are present in the nl msg */
1510static bool ipip6_netlink_6rd_parms(struct nlattr *data[],
1511 struct ip_tunnel_6rd *ip6rd)
1512{
1513 bool ret = false;
1514 memset(ip6rd, 0, sizeof(*ip6rd));
1515
1516 if (!data)
1517 return ret;
1518
1519 if (data[IFLA_IPTUN_6RD_PREFIX]) {
1520 ret = true;
1521 ip6rd->prefix = nla_get_in6_addr(data[IFLA_IPTUN_6RD_PREFIX]);
1522 }
1523
1524 if (data[IFLA_IPTUN_6RD_RELAY_PREFIX]) {
1525 ret = true;
1526 ip6rd->relay_prefix =
1527 nla_get_be32(data[IFLA_IPTUN_6RD_RELAY_PREFIX]);
1528 }
1529
1530 if (data[IFLA_IPTUN_6RD_PREFIXLEN]) {
1531 ret = true;
1532 ip6rd->prefixlen = nla_get_u16(data[IFLA_IPTUN_6RD_PREFIXLEN]);
1533 }
1534
1535 if (data[IFLA_IPTUN_6RD_RELAY_PREFIXLEN]) {
1536 ret = true;
1537 ip6rd->relay_prefixlen =
1538 nla_get_u16(data[IFLA_IPTUN_6RD_RELAY_PREFIXLEN]);
1539 }
1540
1541 return ret;
1542}
1543#endif
1544
1545static int ipip6_newlink(struct net_device *dev,
1546 struct rtnl_newlink_params *params,
1547 struct netlink_ext_ack *extack)
1548{
1549 struct nlattr **data = params->data;
1550 struct nlattr **tb = params->tb;
1551 struct ip_tunnel *nt;
1552 struct ip_tunnel_encap ipencap;
1553#ifdef CONFIG_IPV6_SIT_6RD
1554 struct ip_tunnel_6rd ip6rd;
1555#endif
1556 struct net *net;
1557 int err;
1558
1559 net = params->link_net ? : dev_net(dev);
1560 nt = netdev_priv(dev);
1561 nt->net = net;
1562
1563 if (ip_tunnel_netlink_encap_parms(data, encap: &ipencap)) {
1564 err = ip_tunnel_encap_setup(t: nt, ipencap: &ipencap);
1565 if (err < 0)
1566 return err;
1567 }
1568
1569 ipip6_netlink_parms(data, parms: &nt->parms, fwmark: &nt->fwmark);
1570
1571 if (ipip6_tunnel_locate(net, parms: &nt->parms, create: 0))
1572 return -EEXIST;
1573
1574 err = ipip6_tunnel_create(dev);
1575 if (err < 0)
1576 return err;
1577
1578 if (tb[IFLA_MTU]) {
1579 u32 mtu = nla_get_u32(nla: tb[IFLA_MTU]);
1580
1581 if (mtu >= IPV6_MIN_MTU &&
1582 mtu <= IP6_MAX_MTU - dev->hard_header_len)
1583 dev->mtu = mtu;
1584 }
1585
1586#ifdef CONFIG_IPV6_SIT_6RD
1587 if (ipip6_netlink_6rd_parms(data, &ip6rd)) {
1588 err = ipip6_tunnel_update_6rd(nt, &ip6rd);
1589 if (err < 0)
1590 unregister_netdevice_queue(dev, NULL);
1591 }
1592#endif
1593
1594 return err;
1595}
1596
1597static int ipip6_changelink(struct net_device *dev, struct nlattr *tb[],
1598 struct nlattr *data[],
1599 struct netlink_ext_ack *extack)
1600{
1601 struct ip_tunnel *t = netdev_priv(dev);
1602 struct ip_tunnel_encap ipencap;
1603 struct ip_tunnel_parm_kern p;
1604 struct net *net = t->net;
1605 struct sit_net *sitn = net_generic(net, id: sit_net_id);
1606#ifdef CONFIG_IPV6_SIT_6RD
1607 struct ip_tunnel_6rd ip6rd;
1608#endif
1609 __u32 fwmark = t->fwmark;
1610 int err;
1611
1612 if (dev == sitn->fb_tunnel_dev)
1613 return -EINVAL;
1614
1615 if (ip_tunnel_netlink_encap_parms(data, encap: &ipencap)) {
1616 err = ip_tunnel_encap_setup(t, ipencap: &ipencap);
1617 if (err < 0)
1618 return err;
1619 }
1620
1621 ipip6_netlink_parms(data, parms: &p, fwmark: &fwmark);
1622
1623 if (((dev->flags & IFF_POINTOPOINT) && !p.iph.daddr) ||
1624 (!(dev->flags & IFF_POINTOPOINT) && p.iph.daddr))
1625 return -EINVAL;
1626
1627 t = ipip6_tunnel_locate(net, parms: &p, create: 0);
1628
1629 if (t) {
1630 if (t->dev != dev)
1631 return -EEXIST;
1632 } else
1633 t = netdev_priv(dev);
1634
1635 ipip6_tunnel_update(t, p: &p, fwmark);
1636
1637#ifdef CONFIG_IPV6_SIT_6RD
1638 if (ipip6_netlink_6rd_parms(data, &ip6rd))
1639 return ipip6_tunnel_update_6rd(t, &ip6rd);
1640#endif
1641
1642 return 0;
1643}
1644
1645static size_t ipip6_get_size(const struct net_device *dev)
1646{
1647 return
1648 /* IFLA_IPTUN_LINK */
1649 nla_total_size(payload: 4) +
1650 /* IFLA_IPTUN_LOCAL */
1651 nla_total_size(payload: 4) +
1652 /* IFLA_IPTUN_REMOTE */
1653 nla_total_size(payload: 4) +
1654 /* IFLA_IPTUN_TTL */
1655 nla_total_size(payload: 1) +
1656 /* IFLA_IPTUN_TOS */
1657 nla_total_size(payload: 1) +
1658 /* IFLA_IPTUN_PMTUDISC */
1659 nla_total_size(payload: 1) +
1660 /* IFLA_IPTUN_FLAGS */
1661 nla_total_size(payload: 2) +
1662 /* IFLA_IPTUN_PROTO */
1663 nla_total_size(payload: 1) +
1664#ifdef CONFIG_IPV6_SIT_6RD
1665 /* IFLA_IPTUN_6RD_PREFIX */
1666 nla_total_size(sizeof(struct in6_addr)) +
1667 /* IFLA_IPTUN_6RD_RELAY_PREFIX */
1668 nla_total_size(4) +
1669 /* IFLA_IPTUN_6RD_PREFIXLEN */
1670 nla_total_size(2) +
1671 /* IFLA_IPTUN_6RD_RELAY_PREFIXLEN */
1672 nla_total_size(2) +
1673#endif
1674 /* IFLA_IPTUN_ENCAP_TYPE */
1675 nla_total_size(payload: 2) +
1676 /* IFLA_IPTUN_ENCAP_FLAGS */
1677 nla_total_size(payload: 2) +
1678 /* IFLA_IPTUN_ENCAP_SPORT */
1679 nla_total_size(payload: 2) +
1680 /* IFLA_IPTUN_ENCAP_DPORT */
1681 nla_total_size(payload: 2) +
1682 /* IFLA_IPTUN_FWMARK */
1683 nla_total_size(payload: 4) +
1684 0;
1685}
1686
1687static int ipip6_fill_info(struct sk_buff *skb, const struct net_device *dev)
1688{
1689 struct ip_tunnel *tunnel = netdev_priv(dev);
1690 struct ip_tunnel_parm_kern *parm = &tunnel->parms;
1691
1692 if (nla_put_u32(skb, attrtype: IFLA_IPTUN_LINK, value: parm->link) ||
1693 nla_put_in_addr(skb, attrtype: IFLA_IPTUN_LOCAL, addr: parm->iph.saddr) ||
1694 nla_put_in_addr(skb, attrtype: IFLA_IPTUN_REMOTE, addr: parm->iph.daddr) ||
1695 nla_put_u8(skb, attrtype: IFLA_IPTUN_TTL, value: parm->iph.ttl) ||
1696 nla_put_u8(skb, attrtype: IFLA_IPTUN_TOS, value: parm->iph.tos) ||
1697 nla_put_u8(skb, attrtype: IFLA_IPTUN_PMTUDISC,
1698 value: !!(parm->iph.frag_off & htons(IP_DF))) ||
1699 nla_put_u8(skb, attrtype: IFLA_IPTUN_PROTO, value: parm->iph.protocol) ||
1700 nla_put_be16(skb, attrtype: IFLA_IPTUN_FLAGS,
1701 value: ip_tunnel_flags_to_be16(flags: parm->i_flags)) ||
1702 nla_put_u32(skb, attrtype: IFLA_IPTUN_FWMARK, value: tunnel->fwmark))
1703 goto nla_put_failure;
1704
1705#ifdef CONFIG_IPV6_SIT_6RD
1706 if (nla_put_in6_addr(skb, IFLA_IPTUN_6RD_PREFIX,
1707 &tunnel->ip6rd.prefix) ||
1708 nla_put_in_addr(skb, IFLA_IPTUN_6RD_RELAY_PREFIX,
1709 tunnel->ip6rd.relay_prefix) ||
1710 nla_put_u16(skb, IFLA_IPTUN_6RD_PREFIXLEN,
1711 tunnel->ip6rd.prefixlen) ||
1712 nla_put_u16(skb, IFLA_IPTUN_6RD_RELAY_PREFIXLEN,
1713 tunnel->ip6rd.relay_prefixlen))
1714 goto nla_put_failure;
1715#endif
1716
1717 if (nla_put_u16(skb, attrtype: IFLA_IPTUN_ENCAP_TYPE,
1718 value: tunnel->encap.type) ||
1719 nla_put_be16(skb, attrtype: IFLA_IPTUN_ENCAP_SPORT,
1720 value: tunnel->encap.sport) ||
1721 nla_put_be16(skb, attrtype: IFLA_IPTUN_ENCAP_DPORT,
1722 value: tunnel->encap.dport) ||
1723 nla_put_u16(skb, attrtype: IFLA_IPTUN_ENCAP_FLAGS,
1724 value: tunnel->encap.flags))
1725 goto nla_put_failure;
1726
1727 return 0;
1728
1729nla_put_failure:
1730 return -EMSGSIZE;
1731}
1732
1733static const struct nla_policy ipip6_policy[IFLA_IPTUN_MAX + 1] = {
1734 [IFLA_IPTUN_LINK] = { .type = NLA_U32 },
1735 [IFLA_IPTUN_LOCAL] = { .type = NLA_U32 },
1736 [IFLA_IPTUN_REMOTE] = { .type = NLA_U32 },
1737 [IFLA_IPTUN_TTL] = { .type = NLA_U8 },
1738 [IFLA_IPTUN_TOS] = { .type = NLA_U8 },
1739 [IFLA_IPTUN_PMTUDISC] = { .type = NLA_U8 },
1740 [IFLA_IPTUN_FLAGS] = { .type = NLA_U16 },
1741 [IFLA_IPTUN_PROTO] = { .type = NLA_U8 },
1742#ifdef CONFIG_IPV6_SIT_6RD
1743 [IFLA_IPTUN_6RD_PREFIX] = { .len = sizeof(struct in6_addr) },
1744 [IFLA_IPTUN_6RD_RELAY_PREFIX] = { .type = NLA_U32 },
1745 [IFLA_IPTUN_6RD_PREFIXLEN] = { .type = NLA_U16 },
1746 [IFLA_IPTUN_6RD_RELAY_PREFIXLEN] = { .type = NLA_U16 },
1747#endif
1748 [IFLA_IPTUN_ENCAP_TYPE] = { .type = NLA_U16 },
1749 [IFLA_IPTUN_ENCAP_FLAGS] = { .type = NLA_U16 },
1750 [IFLA_IPTUN_ENCAP_SPORT] = { .type = NLA_U16 },
1751 [IFLA_IPTUN_ENCAP_DPORT] = { .type = NLA_U16 },
1752 [IFLA_IPTUN_FWMARK] = { .type = NLA_U32 },
1753};
1754
1755static void ipip6_dellink(struct net_device *dev, struct list_head *head)
1756{
1757 struct net *net = dev_net(dev);
1758 struct sit_net *sitn = net_generic(net, id: sit_net_id);
1759
1760 if (dev != sitn->fb_tunnel_dev)
1761 unregister_netdevice_queue(dev, head);
1762}
1763
1764static struct rtnl_link_ops sit_link_ops __read_mostly = {
1765 .kind = "sit",
1766 .maxtype = IFLA_IPTUN_MAX,
1767 .policy = ipip6_policy,
1768 .priv_size = sizeof(struct ip_tunnel),
1769 .setup = ipip6_tunnel_setup,
1770 .validate = ipip6_validate,
1771 .newlink = ipip6_newlink,
1772 .changelink = ipip6_changelink,
1773 .get_size = ipip6_get_size,
1774 .fill_info = ipip6_fill_info,
1775 .dellink = ipip6_dellink,
1776 .get_link_net = ip_tunnel_get_link_net,
1777};
1778
1779static struct xfrm_tunnel sit_handler __read_mostly = {
1780 .handler = ipip6_rcv,
1781 .err_handler = ipip6_err,
1782 .priority = 1,
1783};
1784
1785static struct xfrm_tunnel ipip_handler __read_mostly = {
1786 .handler = ipip_rcv,
1787 .err_handler = ipip6_err,
1788 .priority = 2,
1789};
1790
1791#if IS_ENABLED(CONFIG_MPLS)
1792static struct xfrm_tunnel mplsip_handler __read_mostly = {
1793 .handler = mplsip_rcv,
1794 .err_handler = ipip6_err,
1795 .priority = 2,
1796};
1797#endif
1798
1799static void __net_exit sit_exit_rtnl_net(struct net *net, struct list_head *head)
1800{
1801 struct sit_net *sitn = net_generic(net, id: sit_net_id);
1802 struct net_device *dev, *aux;
1803 int prio;
1804
1805 for_each_netdev_safe(net, dev, aux)
1806 if (dev->rtnl_link_ops == &sit_link_ops)
1807 unregister_netdevice_queue(dev, head);
1808
1809 for (prio = 0; prio < 4; prio++) {
1810 int h;
1811 for (h = 0; h < (prio ? IP6_SIT_HASH_SIZE : 1); h++) {
1812 struct ip_tunnel *t;
1813
1814 t = rtnl_net_dereference(net, sitn->tunnels[prio][h]);
1815 while (t) {
1816 /* If dev is in the same netns, it has already
1817 * been added to the list by the previous loop.
1818 */
1819 if (!net_eq(net1: dev_net(dev: t->dev), net2: net))
1820 unregister_netdevice_queue(dev: t->dev, head);
1821
1822 t = rtnl_net_dereference(net, t->next);
1823 }
1824 }
1825 }
1826}
1827
1828static int __net_init sit_init_net(struct net *net)
1829{
1830 struct sit_net *sitn = net_generic(net, id: sit_net_id);
1831 struct ip_tunnel *t;
1832 int err;
1833
1834 sitn->tunnels[0] = sitn->tunnels_wc;
1835 sitn->tunnels[1] = sitn->tunnels_l;
1836 sitn->tunnels[2] = sitn->tunnels_r;
1837 sitn->tunnels[3] = sitn->tunnels_r_l;
1838
1839 if (!net_has_fallback_tunnels(net))
1840 return 0;
1841
1842 sitn->fb_tunnel_dev = alloc_netdev(sizeof(struct ip_tunnel), "sit0",
1843 NET_NAME_UNKNOWN,
1844 ipip6_tunnel_setup);
1845 if (!sitn->fb_tunnel_dev) {
1846 err = -ENOMEM;
1847 goto err_alloc_dev;
1848 }
1849 dev_net_set(dev: sitn->fb_tunnel_dev, net);
1850 sitn->fb_tunnel_dev->rtnl_link_ops = &sit_link_ops;
1851 /* FB netdevice is special: we have one, and only one per netns.
1852 * Allowing to move it to another netns is clearly unsafe.
1853 */
1854 sitn->fb_tunnel_dev->netns_immutable = true;
1855
1856 t = netdev_priv(dev: sitn->fb_tunnel_dev);
1857 t->net = net;
1858
1859 err = register_netdev(dev: sitn->fb_tunnel_dev);
1860 if (err)
1861 goto err_reg_dev;
1862
1863 ipip6_tunnel_clone_6rd(dev: sitn->fb_tunnel_dev, sitn);
1864 ipip6_fb_tunnel_init(dev: sitn->fb_tunnel_dev);
1865
1866 strcpy(t->parms.name, sitn->fb_tunnel_dev->name);
1867 return 0;
1868
1869err_reg_dev:
1870 free_netdev(dev: sitn->fb_tunnel_dev);
1871err_alloc_dev:
1872 return err;
1873}
1874
1875static struct pernet_operations sit_net_ops = {
1876 .init = sit_init_net,
1877 .exit_rtnl = sit_exit_rtnl_net,
1878 .id = &sit_net_id,
1879 .size = sizeof(struct sit_net),
1880};
1881
1882static void __exit sit_cleanup(void)
1883{
1884 rtnl_link_unregister(ops: &sit_link_ops);
1885 xfrm4_tunnel_deregister(handler: &sit_handler, AF_INET6);
1886 xfrm4_tunnel_deregister(handler: &ipip_handler, AF_INET);
1887#if IS_ENABLED(CONFIG_MPLS)
1888 xfrm4_tunnel_deregister(&mplsip_handler, AF_MPLS);
1889#endif
1890
1891 unregister_pernet_device(&sit_net_ops);
1892 rcu_barrier(); /* Wait for completion of call_rcu()'s */
1893}
1894
1895static int __init sit_init(void)
1896{
1897 int err;
1898
1899 pr_info("IPv6, IPv4 and MPLS over IPv4 tunneling driver\n");
1900
1901 err = register_pernet_device(&sit_net_ops);
1902 if (err < 0)
1903 return err;
1904 err = xfrm4_tunnel_register(handler: &sit_handler, AF_INET6);
1905 if (err < 0) {
1906 pr_info("%s: can't register ip6ip4\n", __func__);
1907 goto xfrm_tunnel_failed;
1908 }
1909 err = xfrm4_tunnel_register(handler: &ipip_handler, AF_INET);
1910 if (err < 0) {
1911 pr_info("%s: can't register ip4ip4\n", __func__);
1912 goto xfrm_tunnel4_failed;
1913 }
1914#if IS_ENABLED(CONFIG_MPLS)
1915 err = xfrm4_tunnel_register(&mplsip_handler, AF_MPLS);
1916 if (err < 0) {
1917 pr_info("%s: can't register mplsip\n", __func__);
1918 goto xfrm_tunnel_mpls_failed;
1919 }
1920#endif
1921 err = rtnl_link_register(ops: &sit_link_ops);
1922 if (err < 0)
1923 goto rtnl_link_failed;
1924
1925out:
1926 return err;
1927
1928rtnl_link_failed:
1929#if IS_ENABLED(CONFIG_MPLS)
1930 xfrm4_tunnel_deregister(&mplsip_handler, AF_MPLS);
1931xfrm_tunnel_mpls_failed:
1932#endif
1933 xfrm4_tunnel_deregister(handler: &ipip_handler, AF_INET);
1934xfrm_tunnel4_failed:
1935 xfrm4_tunnel_deregister(handler: &sit_handler, AF_INET6);
1936xfrm_tunnel_failed:
1937 unregister_pernet_device(&sit_net_ops);
1938 goto out;
1939}
1940
1941module_init(sit_init);
1942module_exit(sit_cleanup);
1943MODULE_DESCRIPTION("IPv6-in-IPv4 tunnel SIT driver");
1944MODULE_LICENSE("GPL");
1945MODULE_ALIAS_RTNL_LINK("sit");
1946MODULE_ALIAS_NETDEV("sit0");
1947