1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * GRE over IPv6 protocol decoder.
4 *
5 * Authors: Dmitry Kozlov (xeb@mail.ru)
6 */
7
8#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
9
10#include <linux/capability.h>
11#include <linux/module.h>
12#include <linux/types.h>
13#include <linux/kernel.h>
14#include <linux/slab.h>
15#include <linux/uaccess.h>
16#include <linux/skbuff.h>
17#include <linux/netdevice.h>
18#include <linux/in.h>
19#include <linux/tcp.h>
20#include <linux/udp.h>
21#include <linux/if_arp.h>
22#include <linux/init.h>
23#include <linux/in6.h>
24#include <linux/inetdevice.h>
25#include <linux/igmp.h>
26#include <linux/netfilter_ipv4.h>
27#include <linux/etherdevice.h>
28#include <linux/if_ether.h>
29#include <linux/hash.h>
30#include <linux/if_tunnel.h>
31#include <linux/ip6_tunnel.h>
32
33#include <net/sock.h>
34#include <net/ip.h>
35#include <net/ip_tunnels.h>
36#include <net/icmp.h>
37#include <net/protocol.h>
38#include <net/addrconf.h>
39#include <net/arp.h>
40#include <net/checksum.h>
41#include <net/dsfield.h>
42#include <net/inet_ecn.h>
43#include <net/xfrm.h>
44#include <net/net_namespace.h>
45#include <net/netns/generic.h>
46#include <net/rtnetlink.h>
47
48#include <net/ipv6.h>
49#include <net/ip6_fib.h>
50#include <net/ip6_route.h>
51#include <net/ip6_tunnel.h>
52#include <net/gre.h>
53#include <net/erspan.h>
54#include <net/dst_metadata.h>
55
56
57static bool log_ecn_error = true;
58module_param(log_ecn_error, bool, 0644);
59MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN");
60
61#define IP6_GRE_HASH_SIZE_SHIFT 5
62#define IP6_GRE_HASH_SIZE (1 << IP6_GRE_HASH_SIZE_SHIFT)
63
64static unsigned int ip6gre_net_id __read_mostly;
65struct ip6gre_net {
66 struct ip6_tnl __rcu *tunnels[4][IP6_GRE_HASH_SIZE];
67
68 struct ip6_tnl __rcu *collect_md_tun;
69 struct ip6_tnl __rcu *collect_md_tun_erspan;
70 struct net_device *fb_tunnel_dev;
71};
72
73static struct rtnl_link_ops ip6gre_link_ops __read_mostly;
74static struct rtnl_link_ops ip6gre_tap_ops __read_mostly;
75static struct rtnl_link_ops ip6erspan_tap_ops __read_mostly;
76static int ip6gre_tunnel_init(struct net_device *dev);
77static void ip6gre_tunnel_setup(struct net_device *dev);
78static void ip6gre_tunnel_link(struct ip6gre_net *ign, struct ip6_tnl *t);
79static void ip6gre_tnl_link_config(struct ip6_tnl *t, int set_mtu);
80static void ip6erspan_tnl_link_config(struct ip6_tnl *t, int set_mtu);
81
82/* Tunnel hash table */
83
84/*
85 4 hash tables:
86
87 3: (remote,local)
88 2: (remote,*)
89 1: (*,local)
90 0: (*,*)
91
92 We require exact key match i.e. if a key is present in packet
93 it will match only tunnel with the same key; if it is not present,
94 it will match only keyless tunnel.
95
96 All keysless packets, if not matched configured keyless tunnels
97 will match fallback tunnel.
98 */
99
100#define HASH_KEY(key) (((__force u32)key^((__force u32)key>>4))&(IP6_GRE_HASH_SIZE - 1))
101static u32 HASH_ADDR(const struct in6_addr *addr)
102{
103 u32 hash = ipv6_addr_hash(a: addr);
104
105 return hash_32(val: hash, IP6_GRE_HASH_SIZE_SHIFT);
106}
107
108#define tunnels_r_l tunnels[3]
109#define tunnels_r tunnels[2]
110#define tunnels_l tunnels[1]
111#define tunnels_wc tunnels[0]
112
113/* Given src, dst and key, find appropriate for input tunnel. */
114
115static struct ip6_tnl *ip6gre_tunnel_lookup(struct net_device *dev,
116 const struct in6_addr *remote, const struct in6_addr *local,
117 __be32 key, __be16 gre_proto)
118{
119 struct net *net = dev_net(dev);
120 int link = dev->ifindex;
121 unsigned int h0 = HASH_ADDR(addr: remote);
122 unsigned int h1 = HASH_KEY(key);
123 struct ip6_tnl *t, *cand = NULL;
124 struct ip6gre_net *ign = net_generic(net, id: ip6gre_net_id);
125 int dev_type = (gre_proto == htons(ETH_P_TEB) ||
126 gre_proto == htons(ETH_P_ERSPAN) ||
127 gre_proto == htons(ETH_P_ERSPAN2)) ?
128 ARPHRD_ETHER : ARPHRD_IP6GRE;
129 int score, cand_score = 4;
130 struct net_device *ndev;
131
132 for_each_ip_tunnel_rcu(t, ign->tunnels_r_l[h0 ^ h1]) {
133 if (!ipv6_addr_equal(a1: local, a2: &t->parms.laddr) ||
134 !ipv6_addr_equal(a1: remote, a2: &t->parms.raddr) ||
135 key != t->parms.i_key ||
136 !(t->dev->flags & IFF_UP))
137 continue;
138
139 if (t->dev->type != ARPHRD_IP6GRE &&
140 t->dev->type != dev_type)
141 continue;
142
143 score = 0;
144 if (t->parms.link != link)
145 score |= 1;
146 if (t->dev->type != dev_type)
147 score |= 2;
148 if (score == 0)
149 return t;
150
151 if (score < cand_score) {
152 cand = t;
153 cand_score = score;
154 }
155 }
156
157 for_each_ip_tunnel_rcu(t, ign->tunnels_r[h0 ^ h1]) {
158 if (!ipv6_addr_equal(a1: remote, a2: &t->parms.raddr) ||
159 key != t->parms.i_key ||
160 !(t->dev->flags & IFF_UP))
161 continue;
162
163 if (t->dev->type != ARPHRD_IP6GRE &&
164 t->dev->type != dev_type)
165 continue;
166
167 score = 0;
168 if (t->parms.link != link)
169 score |= 1;
170 if (t->dev->type != dev_type)
171 score |= 2;
172 if (score == 0)
173 return t;
174
175 if (score < cand_score) {
176 cand = t;
177 cand_score = score;
178 }
179 }
180
181 for_each_ip_tunnel_rcu(t, ign->tunnels_l[h1]) {
182 if ((!ipv6_addr_equal(a1: local, a2: &t->parms.laddr) &&
183 (!ipv6_addr_equal(a1: local, a2: &t->parms.raddr) ||
184 !ipv6_addr_is_multicast(addr: local))) ||
185 key != t->parms.i_key ||
186 !(t->dev->flags & IFF_UP))
187 continue;
188
189 if (t->dev->type != ARPHRD_IP6GRE &&
190 t->dev->type != dev_type)
191 continue;
192
193 score = 0;
194 if (t->parms.link != link)
195 score |= 1;
196 if (t->dev->type != dev_type)
197 score |= 2;
198 if (score == 0)
199 return t;
200
201 if (score < cand_score) {
202 cand = t;
203 cand_score = score;
204 }
205 }
206
207 for_each_ip_tunnel_rcu(t, ign->tunnels_wc[h1]) {
208 if (t->parms.i_key != key ||
209 !(t->dev->flags & IFF_UP))
210 continue;
211
212 if (t->dev->type != ARPHRD_IP6GRE &&
213 t->dev->type != dev_type)
214 continue;
215
216 score = 0;
217 if (t->parms.link != link)
218 score |= 1;
219 if (t->dev->type != dev_type)
220 score |= 2;
221 if (score == 0)
222 return t;
223
224 if (score < cand_score) {
225 cand = t;
226 cand_score = score;
227 }
228 }
229
230 if (cand)
231 return cand;
232
233 if (gre_proto == htons(ETH_P_ERSPAN) ||
234 gre_proto == htons(ETH_P_ERSPAN2))
235 t = rcu_dereference(ign->collect_md_tun_erspan);
236 else
237 t = rcu_dereference(ign->collect_md_tun);
238
239 if (t && t->dev->flags & IFF_UP)
240 return t;
241
242 ndev = READ_ONCE(ign->fb_tunnel_dev);
243 if (ndev && ndev->flags & IFF_UP)
244 return netdev_priv(dev: ndev);
245
246 return NULL;
247}
248
249static struct ip6_tnl __rcu **__ip6gre_bucket(struct ip6gre_net *ign,
250 const struct __ip6_tnl_parm *p)
251{
252 const struct in6_addr *remote = &p->raddr;
253 const struct in6_addr *local = &p->laddr;
254 unsigned int h = HASH_KEY(p->i_key);
255 int prio = 0;
256
257 if (!ipv6_addr_any(a: local))
258 prio |= 1;
259 if (!ipv6_addr_any(a: remote) && !ipv6_addr_is_multicast(addr: remote)) {
260 prio |= 2;
261 h ^= HASH_ADDR(addr: remote);
262 }
263
264 return &ign->tunnels[prio][h];
265}
266
267static void ip6gre_tunnel_link_md(struct ip6gre_net *ign, struct ip6_tnl *t)
268{
269 if (t->parms.collect_md)
270 rcu_assign_pointer(ign->collect_md_tun, t);
271}
272
273static void ip6erspan_tunnel_link_md(struct ip6gre_net *ign, struct ip6_tnl *t)
274{
275 if (t->parms.collect_md)
276 rcu_assign_pointer(ign->collect_md_tun_erspan, t);
277}
278
279static void ip6gre_tunnel_unlink_md(struct ip6gre_net *ign, struct ip6_tnl *t)
280{
281 if (t->parms.collect_md)
282 rcu_assign_pointer(ign->collect_md_tun, NULL);
283}
284
285static void ip6erspan_tunnel_unlink_md(struct ip6gre_net *ign,
286 struct ip6_tnl *t)
287{
288 if (t->parms.collect_md)
289 rcu_assign_pointer(ign->collect_md_tun_erspan, NULL);
290}
291
292static inline struct ip6_tnl __rcu **ip6gre_bucket(struct ip6gre_net *ign,
293 const struct ip6_tnl *t)
294{
295 return __ip6gre_bucket(ign, p: &t->parms);
296}
297
298static void ip6gre_tunnel_link(struct ip6gre_net *ign, struct ip6_tnl *t)
299{
300 struct ip6_tnl __rcu **tp = ip6gre_bucket(ign, t);
301
302 rcu_assign_pointer(t->next, rtnl_dereference(*tp));
303 rcu_assign_pointer(*tp, t);
304}
305
306static void ip6gre_tunnel_unlink(struct ip6gre_net *ign, struct ip6_tnl *t)
307{
308 struct ip6_tnl __rcu **tp;
309 struct ip6_tnl *iter;
310
311 for (tp = ip6gre_bucket(ign, t);
312 (iter = rtnl_dereference(*tp)) != NULL;
313 tp = &iter->next) {
314 if (t == iter) {
315 rcu_assign_pointer(*tp, t->next);
316 break;
317 }
318 }
319}
320
321static struct ip6_tnl *ip6gre_tunnel_find(struct net *net,
322 const struct __ip6_tnl_parm *parms,
323 int type)
324{
325 const struct in6_addr *remote = &parms->raddr;
326 const struct in6_addr *local = &parms->laddr;
327 __be32 key = parms->i_key;
328 int link = parms->link;
329 struct ip6_tnl *t;
330 struct ip6_tnl __rcu **tp;
331 struct ip6gre_net *ign = net_generic(net, id: ip6gre_net_id);
332
333 for (tp = __ip6gre_bucket(ign, p: parms);
334 (t = rtnl_dereference(*tp)) != NULL;
335 tp = &t->next)
336 if (ipv6_addr_equal(a1: local, a2: &t->parms.laddr) &&
337 ipv6_addr_equal(a1: remote, a2: &t->parms.raddr) &&
338 key == t->parms.i_key &&
339 link == t->parms.link &&
340 type == t->dev->type)
341 break;
342
343 return t;
344}
345
346static struct ip6_tnl *ip6gre_tunnel_locate(struct net *net,
347 const struct __ip6_tnl_parm *parms, int create)
348{
349 struct ip6_tnl *t, *nt;
350 struct net_device *dev;
351 char name[IFNAMSIZ];
352 struct ip6gre_net *ign = net_generic(net, id: ip6gre_net_id);
353
354 t = ip6gre_tunnel_find(net, parms, ARPHRD_IP6GRE);
355 if (t && create)
356 return NULL;
357 if (t || !create)
358 return t;
359
360 if (parms->name[0]) {
361 if (!dev_valid_name(name: parms->name))
362 return NULL;
363 strscpy(p: name, q: parms->name, IFNAMSIZ);
364 } else {
365 strcpy(p: name, q: "ip6gre%d");
366 }
367 dev = alloc_netdev(sizeof(*t), name, NET_NAME_UNKNOWN,
368 ip6gre_tunnel_setup);
369 if (!dev)
370 return NULL;
371
372 dev_net_set(dev, net);
373
374 nt = netdev_priv(dev);
375 nt->parms = *parms;
376 dev->rtnl_link_ops = &ip6gre_link_ops;
377
378 nt->dev = dev;
379 nt->net = dev_net(dev);
380
381 if (register_netdevice(dev) < 0)
382 goto failed_free;
383
384 ip6gre_tnl_link_config(t: nt, set_mtu: 1);
385 ip6gre_tunnel_link(ign, t: nt);
386 return nt;
387
388failed_free:
389 free_netdev(dev);
390 return NULL;
391}
392
393static void ip6erspan_tunnel_uninit(struct net_device *dev)
394{
395 struct ip6_tnl *t = netdev_priv(dev);
396 struct ip6gre_net *ign = net_generic(net: t->net, id: ip6gre_net_id);
397
398 ip6erspan_tunnel_unlink_md(ign, t);
399 ip6gre_tunnel_unlink(ign, t);
400 dst_cache_reset(dst_cache: &t->dst_cache);
401 netdev_put(dev, tracker: &t->dev_tracker);
402}
403
404static void ip6gre_tunnel_uninit(struct net_device *dev)
405{
406 struct ip6_tnl *t = netdev_priv(dev);
407 struct ip6gre_net *ign = net_generic(net: t->net, id: ip6gre_net_id);
408
409 ip6gre_tunnel_unlink_md(ign, t);
410 ip6gre_tunnel_unlink(ign, t);
411 if (ign->fb_tunnel_dev == dev)
412 WRITE_ONCE(ign->fb_tunnel_dev, NULL);
413 dst_cache_reset(dst_cache: &t->dst_cache);
414 netdev_put(dev, tracker: &t->dev_tracker);
415}
416
417
418static int ip6gre_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
419 u8 type, u8 code, int offset, __be32 info)
420{
421 struct net *net = dev_net(dev: skb->dev);
422 const struct ipv6hdr *ipv6h;
423 struct tnl_ptk_info tpi;
424 struct ip6_tnl *t;
425
426 if (gre_parse_header(skb, tpi: &tpi, NULL, htons(ETH_P_IPV6),
427 nhs: offset) < 0)
428 return -EINVAL;
429
430 ipv6h = (const struct ipv6hdr *)skb->data;
431 t = ip6gre_tunnel_lookup(dev: skb->dev, remote: &ipv6h->daddr, local: &ipv6h->saddr,
432 key: tpi.key, gre_proto: tpi.proto);
433 if (!t)
434 return -ENOENT;
435
436 switch (type) {
437 case ICMPV6_DEST_UNREACH:
438 net_dbg_ratelimited("%s: Path to destination invalid or inactive!\n",
439 t->parms.name);
440 if (code != ICMPV6_PORT_UNREACH)
441 break;
442 return 0;
443 case ICMPV6_TIME_EXCEED:
444 if (code == ICMPV6_EXC_HOPLIMIT) {
445 net_dbg_ratelimited("%s: Too small hop limit or routing loop in tunnel!\n",
446 t->parms.name);
447 break;
448 }
449 return 0;
450 case ICMPV6_PARAMPROB: {
451 struct ipv6_tlv_tnl_enc_lim *tel;
452 __u32 teli;
453
454 teli = 0;
455 if (code == ICMPV6_HDR_FIELD)
456 teli = ip6_tnl_parse_tlv_enc_lim(skb, raw: skb->data);
457
458 if (teli && teli == be32_to_cpu(info) - 2) {
459 tel = (struct ipv6_tlv_tnl_enc_lim *) &skb->data[teli];
460 if (tel->encap_limit == 0) {
461 net_dbg_ratelimited("%s: Too small encapsulation limit or routing loop in tunnel!\n",
462 t->parms.name);
463 }
464 } else {
465 net_dbg_ratelimited("%s: Recipient unable to parse tunneled packet!\n",
466 t->parms.name);
467 }
468 return 0;
469 }
470 case ICMPV6_PKT_TOOBIG:
471 ip6_update_pmtu(skb, net, mtu: info, oif: 0, mark: 0, uid: sock_net_uid(net, NULL));
472 return 0;
473 case NDISC_REDIRECT:
474 ip6_redirect(skb, net, oif: skb->dev->ifindex, mark: 0,
475 uid: sock_net_uid(net, NULL));
476 return 0;
477 }
478
479 if (time_before(jiffies, t->err_time + IP6TUNNEL_ERR_TIMEO))
480 t->err_count++;
481 else
482 t->err_count = 1;
483 t->err_time = jiffies;
484
485 return 0;
486}
487
488static int ip6gre_rcv(struct sk_buff *skb, const struct tnl_ptk_info *tpi)
489{
490 const struct ipv6hdr *ipv6h;
491 struct ip6_tnl *tunnel;
492
493 ipv6h = ipv6_hdr(skb);
494 tunnel = ip6gre_tunnel_lookup(dev: skb->dev,
495 remote: &ipv6h->saddr, local: &ipv6h->daddr, key: tpi->key,
496 gre_proto: tpi->proto);
497 if (tunnel) {
498 if (tunnel->parms.collect_md) {
499 struct metadata_dst *tun_dst;
500 __be64 tun_id;
501 __be16 flags;
502
503 flags = tpi->flags;
504 tun_id = key32_to_tunnel_id(key: tpi->key);
505
506 tun_dst = ipv6_tun_rx_dst(skb, flags, tunnel_id: tun_id, md_size: 0);
507 if (!tun_dst)
508 return PACKET_REJECT;
509
510 ip6_tnl_rcv(tunnel, skb, tpi, tun_dst, log_ecn_error);
511 } else {
512 ip6_tnl_rcv(tunnel, skb, tpi, NULL, log_ecn_error);
513 }
514
515 return PACKET_RCVD;
516 }
517
518 return PACKET_REJECT;
519}
520
521static int ip6erspan_rcv(struct sk_buff *skb,
522 struct tnl_ptk_info *tpi,
523 int gre_hdr_len)
524{
525 struct erspan_base_hdr *ershdr;
526 const struct ipv6hdr *ipv6h;
527 struct erspan_md2 *md2;
528 struct ip6_tnl *tunnel;
529 u8 ver;
530
531 ipv6h = ipv6_hdr(skb);
532 ershdr = (struct erspan_base_hdr *)skb->data;
533 ver = ershdr->ver;
534
535 tunnel = ip6gre_tunnel_lookup(dev: skb->dev,
536 remote: &ipv6h->saddr, local: &ipv6h->daddr, key: tpi->key,
537 gre_proto: tpi->proto);
538 if (tunnel) {
539 int len = erspan_hdr_len(version: ver);
540
541 if (unlikely(!pskb_may_pull(skb, len)))
542 return PACKET_REJECT;
543
544 if (__iptunnel_pull_header(skb, hdr_len: len,
545 htons(ETH_P_TEB),
546 raw_proto: false, xnet: false) < 0)
547 return PACKET_REJECT;
548
549 if (tunnel->parms.collect_md) {
550 struct erspan_metadata *pkt_md, *md;
551 struct metadata_dst *tun_dst;
552 struct ip_tunnel_info *info;
553 unsigned char *gh;
554 __be64 tun_id;
555 __be16 flags;
556
557 tpi->flags |= TUNNEL_KEY;
558 flags = tpi->flags;
559 tun_id = key32_to_tunnel_id(key: tpi->key);
560
561 tun_dst = ipv6_tun_rx_dst(skb, flags, tunnel_id: tun_id,
562 md_size: sizeof(*md));
563 if (!tun_dst)
564 return PACKET_REJECT;
565
566 /* skb can be uncloned in __iptunnel_pull_header, so
567 * old pkt_md is no longer valid and we need to reset
568 * it
569 */
570 gh = skb_network_header(skb) +
571 skb_network_header_len(skb);
572 pkt_md = (struct erspan_metadata *)(gh + gre_hdr_len +
573 sizeof(*ershdr));
574 info = &tun_dst->u.tun_info;
575 md = ip_tunnel_info_opts(info);
576 md->version = ver;
577 md2 = &md->u.md2;
578 memcpy(md2, pkt_md, ver == 1 ? ERSPAN_V1_MDSIZE :
579 ERSPAN_V2_MDSIZE);
580 info->key.tun_flags |= TUNNEL_ERSPAN_OPT;
581 info->options_len = sizeof(*md);
582
583 ip6_tnl_rcv(tunnel, skb, tpi, tun_dst, log_ecn_error);
584
585 } else {
586 ip6_tnl_rcv(tunnel, skb, tpi, NULL, log_ecn_error);
587 }
588
589 return PACKET_RCVD;
590 }
591
592 return PACKET_REJECT;
593}
594
595static int gre_rcv(struct sk_buff *skb)
596{
597 struct tnl_ptk_info tpi;
598 bool csum_err = false;
599 int hdr_len;
600
601 hdr_len = gre_parse_header(skb, tpi: &tpi, csum_err: &csum_err, htons(ETH_P_IPV6), nhs: 0);
602 if (hdr_len < 0)
603 goto drop;
604
605 if (iptunnel_pull_header(skb, hdr_len, inner_proto: tpi.proto, xnet: false))
606 goto drop;
607
608 if (unlikely(tpi.proto == htons(ETH_P_ERSPAN) ||
609 tpi.proto == htons(ETH_P_ERSPAN2))) {
610 if (ip6erspan_rcv(skb, tpi: &tpi, gre_hdr_len: hdr_len) == PACKET_RCVD)
611 return 0;
612 goto out;
613 }
614
615 if (ip6gre_rcv(skb, tpi: &tpi) == PACKET_RCVD)
616 return 0;
617
618out:
619 icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, info: 0);
620drop:
621 kfree_skb(skb);
622 return 0;
623}
624
625static int gre_handle_offloads(struct sk_buff *skb, bool csum)
626{
627 return iptunnel_handle_offloads(skb,
628 gso_type_mask: csum ? SKB_GSO_GRE_CSUM : SKB_GSO_GRE);
629}
630
631static void prepare_ip6gre_xmit_ipv4(struct sk_buff *skb,
632 struct net_device *dev,
633 struct flowi6 *fl6, __u8 *dsfield,
634 int *encap_limit)
635{
636 const struct iphdr *iph = ip_hdr(skb);
637 struct ip6_tnl *t = netdev_priv(dev);
638
639 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
640 *encap_limit = t->parms.encap_limit;
641
642 memcpy(fl6, &t->fl.u.ip6, sizeof(*fl6));
643
644 if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
645 *dsfield = ipv4_get_dsfield(iph);
646 else
647 *dsfield = ip6_tclass(flowinfo: t->parms.flowinfo);
648
649 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
650 fl6->flowi6_mark = skb->mark;
651 else
652 fl6->flowi6_mark = t->parms.fwmark;
653
654 fl6->flowi6_uid = sock_net_uid(net: dev_net(dev), NULL);
655}
656
657static int prepare_ip6gre_xmit_ipv6(struct sk_buff *skb,
658 struct net_device *dev,
659 struct flowi6 *fl6, __u8 *dsfield,
660 int *encap_limit)
661{
662 struct ipv6hdr *ipv6h;
663 struct ip6_tnl *t = netdev_priv(dev);
664 __u16 offset;
665
666 offset = ip6_tnl_parse_tlv_enc_lim(skb, raw: skb_network_header(skb));
667 /* ip6_tnl_parse_tlv_enc_lim() might have reallocated skb->head */
668 ipv6h = ipv6_hdr(skb);
669
670 if (offset > 0) {
671 struct ipv6_tlv_tnl_enc_lim *tel;
672
673 tel = (struct ipv6_tlv_tnl_enc_lim *)&skb_network_header(skb)[offset];
674 if (tel->encap_limit == 0) {
675 icmpv6_ndo_send(skb_in: skb, ICMPV6_PARAMPROB,
676 ICMPV6_HDR_FIELD, info: offset + 2);
677 return -1;
678 }
679 *encap_limit = tel->encap_limit - 1;
680 } else if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) {
681 *encap_limit = t->parms.encap_limit;
682 }
683
684 memcpy(fl6, &t->fl.u.ip6, sizeof(*fl6));
685
686 if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
687 *dsfield = ipv6_get_dsfield(ipv6h);
688 else
689 *dsfield = ip6_tclass(flowinfo: t->parms.flowinfo);
690
691 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FLOWLABEL)
692 fl6->flowlabel |= ip6_flowlabel(hdr: ipv6h);
693
694 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
695 fl6->flowi6_mark = skb->mark;
696 else
697 fl6->flowi6_mark = t->parms.fwmark;
698
699 fl6->flowi6_uid = sock_net_uid(net: dev_net(dev), NULL);
700
701 return 0;
702}
703
704static int prepare_ip6gre_xmit_other(struct sk_buff *skb,
705 struct net_device *dev,
706 struct flowi6 *fl6, __u8 *dsfield,
707 int *encap_limit)
708{
709 struct ip6_tnl *t = netdev_priv(dev);
710
711 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
712 *encap_limit = t->parms.encap_limit;
713
714 memcpy(fl6, &t->fl.u.ip6, sizeof(*fl6));
715
716 if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
717 *dsfield = 0;
718 else
719 *dsfield = ip6_tclass(flowinfo: t->parms.flowinfo);
720
721 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
722 fl6->flowi6_mark = skb->mark;
723 else
724 fl6->flowi6_mark = t->parms.fwmark;
725
726 fl6->flowi6_uid = sock_net_uid(net: dev_net(dev), NULL);
727
728 return 0;
729}
730
731static struct ip_tunnel_info *skb_tunnel_info_txcheck(struct sk_buff *skb)
732{
733 struct ip_tunnel_info *tun_info;
734
735 tun_info = skb_tunnel_info(skb);
736 if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX)))
737 return ERR_PTR(error: -EINVAL);
738
739 return tun_info;
740}
741
742static netdev_tx_t __gre6_xmit(struct sk_buff *skb,
743 struct net_device *dev, __u8 dsfield,
744 struct flowi6 *fl6, int encap_limit,
745 __u32 *pmtu, __be16 proto)
746{
747 struct ip6_tnl *tunnel = netdev_priv(dev);
748 __be16 protocol;
749 __be16 flags;
750
751 if (dev->type == ARPHRD_ETHER)
752 IPCB(skb)->flags = 0;
753
754 if (dev->header_ops && dev->type == ARPHRD_IP6GRE)
755 fl6->daddr = ((struct ipv6hdr *)skb->data)->daddr;
756 else
757 fl6->daddr = tunnel->parms.raddr;
758
759 /* Push GRE header. */
760 protocol = (dev->type == ARPHRD_ETHER) ? htons(ETH_P_TEB) : proto;
761
762 if (tunnel->parms.collect_md) {
763 struct ip_tunnel_info *tun_info;
764 const struct ip_tunnel_key *key;
765 int tun_hlen;
766
767 tun_info = skb_tunnel_info_txcheck(skb);
768 if (IS_ERR(ptr: tun_info) ||
769 unlikely(ip_tunnel_info_af(tun_info) != AF_INET6))
770 return -EINVAL;
771
772 key = &tun_info->key;
773 memset(fl6, 0, sizeof(*fl6));
774 fl6->flowi6_proto = IPPROTO_GRE;
775 fl6->daddr = key->u.ipv6.dst;
776 fl6->flowlabel = key->label;
777 fl6->flowi6_uid = sock_net_uid(net: dev_net(dev), NULL);
778 fl6->fl6_gre_key = tunnel_id_to_key32(tun_id: key->tun_id);
779
780 dsfield = key->tos;
781 flags = key->tun_flags &
782 (TUNNEL_CSUM | TUNNEL_KEY | TUNNEL_SEQ);
783 tun_hlen = gre_calc_hlen(o_flags: flags);
784
785 if (skb_cow_head(skb, headroom: dev->needed_headroom ?: tun_hlen + tunnel->encap_hlen))
786 return -ENOMEM;
787
788 gre_build_header(skb, hdr_len: tun_hlen,
789 flags, proto: protocol,
790 key: tunnel_id_to_key32(tun_id: tun_info->key.tun_id),
791 seq: (flags & TUNNEL_SEQ) ? htonl(atomic_fetch_inc(&tunnel->o_seqno))
792 : 0);
793
794 } else {
795 if (skb_cow_head(skb, headroom: dev->needed_headroom ?: tunnel->hlen))
796 return -ENOMEM;
797
798 flags = tunnel->parms.o_flags;
799
800 gre_build_header(skb, hdr_len: tunnel->tun_hlen, flags,
801 proto: protocol, key: tunnel->parms.o_key,
802 seq: (flags & TUNNEL_SEQ) ? htonl(atomic_fetch_inc(&tunnel->o_seqno))
803 : 0);
804 }
805
806 return ip6_tnl_xmit(skb, dev, dsfield, fl6, encap_limit, pmtu,
807 NEXTHDR_GRE);
808}
809
810static inline int ip6gre_xmit_ipv4(struct sk_buff *skb, struct net_device *dev)
811{
812 struct ip6_tnl *t = netdev_priv(dev);
813 int encap_limit = -1;
814 struct flowi6 fl6;
815 __u8 dsfield = 0;
816 __u32 mtu;
817 int err;
818
819 memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
820
821 if (!t->parms.collect_md)
822 prepare_ip6gre_xmit_ipv4(skb, dev, fl6: &fl6,
823 dsfield: &dsfield, encap_limit: &encap_limit);
824
825 err = gre_handle_offloads(skb, csum: !!(t->parms.o_flags & TUNNEL_CSUM));
826 if (err)
827 return -1;
828
829 err = __gre6_xmit(skb, dev, dsfield, fl6: &fl6, encap_limit, pmtu: &mtu,
830 proto: skb->protocol);
831 if (err != 0) {
832 /* XXX: send ICMP error even if DF is not set. */
833 if (err == -EMSGSIZE)
834 icmp_ndo_send(skb_in: skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
835 htonl(mtu));
836 return -1;
837 }
838
839 return 0;
840}
841
842static inline int ip6gre_xmit_ipv6(struct sk_buff *skb, struct net_device *dev)
843{
844 struct ip6_tnl *t = netdev_priv(dev);
845 struct ipv6hdr *ipv6h = ipv6_hdr(skb);
846 int encap_limit = -1;
847 struct flowi6 fl6;
848 __u8 dsfield = 0;
849 __u32 mtu;
850 int err;
851
852 if (ipv6_addr_equal(a1: &t->parms.raddr, a2: &ipv6h->saddr))
853 return -1;
854
855 if (!t->parms.collect_md &&
856 prepare_ip6gre_xmit_ipv6(skb, dev, fl6: &fl6, dsfield: &dsfield, encap_limit: &encap_limit))
857 return -1;
858
859 if (gre_handle_offloads(skb, csum: !!(t->parms.o_flags & TUNNEL_CSUM)))
860 return -1;
861
862 err = __gre6_xmit(skb, dev, dsfield, fl6: &fl6, encap_limit,
863 pmtu: &mtu, proto: skb->protocol);
864 if (err != 0) {
865 if (err == -EMSGSIZE)
866 icmpv6_ndo_send(skb_in: skb, ICMPV6_PKT_TOOBIG, code: 0, info: mtu);
867 return -1;
868 }
869
870 return 0;
871}
872
873static int ip6gre_xmit_other(struct sk_buff *skb, struct net_device *dev)
874{
875 struct ip6_tnl *t = netdev_priv(dev);
876 int encap_limit = -1;
877 struct flowi6 fl6;
878 __u8 dsfield = 0;
879 __u32 mtu;
880 int err;
881
882 if (!t->parms.collect_md &&
883 prepare_ip6gre_xmit_other(skb, dev, fl6: &fl6, dsfield: &dsfield, encap_limit: &encap_limit))
884 return -1;
885
886 err = gre_handle_offloads(skb, csum: !!(t->parms.o_flags & TUNNEL_CSUM));
887 if (err)
888 return err;
889 err = __gre6_xmit(skb, dev, dsfield, fl6: &fl6, encap_limit, pmtu: &mtu, proto: skb->protocol);
890
891 return err;
892}
893
894static netdev_tx_t ip6gre_tunnel_xmit(struct sk_buff *skb,
895 struct net_device *dev)
896{
897 struct ip6_tnl *t = netdev_priv(dev);
898 __be16 payload_protocol;
899 int ret;
900
901 if (!pskb_inet_may_pull(skb))
902 goto tx_err;
903
904 if (!ip6_tnl_xmit_ctl(t, laddr: &t->parms.laddr, raddr: &t->parms.raddr))
905 goto tx_err;
906
907 payload_protocol = skb_protocol(skb, skip_vlan: true);
908 switch (payload_protocol) {
909 case htons(ETH_P_IP):
910 ret = ip6gre_xmit_ipv4(skb, dev);
911 break;
912 case htons(ETH_P_IPV6):
913 ret = ip6gre_xmit_ipv6(skb, dev);
914 break;
915 default:
916 ret = ip6gre_xmit_other(skb, dev);
917 break;
918 }
919
920 if (ret < 0)
921 goto tx_err;
922
923 return NETDEV_TX_OK;
924
925tx_err:
926 if (!t->parms.collect_md || !IS_ERR(ptr: skb_tunnel_info_txcheck(skb)))
927 DEV_STATS_INC(dev, tx_errors);
928 DEV_STATS_INC(dev, tx_dropped);
929 kfree_skb(skb);
930 return NETDEV_TX_OK;
931}
932
933static netdev_tx_t ip6erspan_tunnel_xmit(struct sk_buff *skb,
934 struct net_device *dev)
935{
936 struct ip_tunnel_info *tun_info = NULL;
937 struct ip6_tnl *t = netdev_priv(dev);
938 struct dst_entry *dst = skb_dst(skb);
939 bool truncate = false;
940 int encap_limit = -1;
941 __u8 dsfield = false;
942 struct flowi6 fl6;
943 int err = -EINVAL;
944 __be16 proto;
945 __u32 mtu;
946 int nhoff;
947
948 if (!pskb_inet_may_pull(skb))
949 goto tx_err;
950
951 if (!ip6_tnl_xmit_ctl(t, laddr: &t->parms.laddr, raddr: &t->parms.raddr))
952 goto tx_err;
953
954 if (gre_handle_offloads(skb, csum: false))
955 goto tx_err;
956
957 if (skb->len > dev->mtu + dev->hard_header_len) {
958 if (pskb_trim(skb, len: dev->mtu + dev->hard_header_len))
959 goto tx_err;
960 truncate = true;
961 }
962
963 nhoff = skb_network_offset(skb);
964 if (skb->protocol == htons(ETH_P_IP) &&
965 (ntohs(ip_hdr(skb)->tot_len) > skb->len - nhoff))
966 truncate = true;
967
968 if (skb->protocol == htons(ETH_P_IPV6)) {
969 int thoff;
970
971 if (skb_transport_header_was_set(skb))
972 thoff = skb_transport_offset(skb);
973 else
974 thoff = nhoff + sizeof(struct ipv6hdr);
975 if (ntohs(ipv6_hdr(skb)->payload_len) > skb->len - thoff)
976 truncate = true;
977 }
978
979 if (skb_cow_head(skb, headroom: dev->needed_headroom ?: t->hlen))
980 goto tx_err;
981
982 t->parms.o_flags &= ~TUNNEL_KEY;
983 IPCB(skb)->flags = 0;
984
985 /* For collect_md mode, derive fl6 from the tunnel key,
986 * for native mode, call prepare_ip6gre_xmit_{ipv4,ipv6}.
987 */
988 if (t->parms.collect_md) {
989 const struct ip_tunnel_key *key;
990 struct erspan_metadata *md;
991 __be32 tun_id;
992
993 tun_info = skb_tunnel_info_txcheck(skb);
994 if (IS_ERR(ptr: tun_info) ||
995 unlikely(ip_tunnel_info_af(tun_info) != AF_INET6))
996 goto tx_err;
997
998 key = &tun_info->key;
999 memset(&fl6, 0, sizeof(fl6));
1000 fl6.flowi6_proto = IPPROTO_GRE;
1001 fl6.daddr = key->u.ipv6.dst;
1002 fl6.flowlabel = key->label;
1003 fl6.flowi6_uid = sock_net_uid(net: dev_net(dev), NULL);
1004 fl6.fl6_gre_key = tunnel_id_to_key32(tun_id: key->tun_id);
1005
1006 dsfield = key->tos;
1007 if (!(tun_info->key.tun_flags & TUNNEL_ERSPAN_OPT))
1008 goto tx_err;
1009 if (tun_info->options_len < sizeof(*md))
1010 goto tx_err;
1011 md = ip_tunnel_info_opts(tun_info);
1012
1013 tun_id = tunnel_id_to_key32(tun_id: key->tun_id);
1014 if (md->version == 1) {
1015 erspan_build_header(skb,
1016 ntohl(tun_id),
1017 ntohl(md->u.index), truncate,
1018 is_ipv4: false);
1019 proto = htons(ETH_P_ERSPAN);
1020 } else if (md->version == 2) {
1021 erspan_build_header_v2(skb,
1022 ntohl(tun_id),
1023 direction: md->u.md2.dir,
1024 hwid: get_hwid(md2: &md->u.md2),
1025 truncate, is_ipv4: false);
1026 proto = htons(ETH_P_ERSPAN2);
1027 } else {
1028 goto tx_err;
1029 }
1030 } else {
1031 switch (skb->protocol) {
1032 case htons(ETH_P_IP):
1033 memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
1034 prepare_ip6gre_xmit_ipv4(skb, dev, fl6: &fl6,
1035 dsfield: &dsfield, encap_limit: &encap_limit);
1036 break;
1037 case htons(ETH_P_IPV6):
1038 if (ipv6_addr_equal(a1: &t->parms.raddr, a2: &ipv6_hdr(skb)->saddr))
1039 goto tx_err;
1040 if (prepare_ip6gre_xmit_ipv6(skb, dev, fl6: &fl6,
1041 dsfield: &dsfield, encap_limit: &encap_limit))
1042 goto tx_err;
1043 break;
1044 default:
1045 memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6));
1046 break;
1047 }
1048
1049 if (t->parms.erspan_ver == 1) {
1050 erspan_build_header(skb, ntohl(t->parms.o_key),
1051 index: t->parms.index,
1052 truncate, is_ipv4: false);
1053 proto = htons(ETH_P_ERSPAN);
1054 } else if (t->parms.erspan_ver == 2) {
1055 erspan_build_header_v2(skb, ntohl(t->parms.o_key),
1056 direction: t->parms.dir,
1057 hwid: t->parms.hwid,
1058 truncate, is_ipv4: false);
1059 proto = htons(ETH_P_ERSPAN2);
1060 } else {
1061 goto tx_err;
1062 }
1063
1064 fl6.daddr = t->parms.raddr;
1065 }
1066
1067 /* Push GRE header. */
1068 gre_build_header(skb, hdr_len: 8, TUNNEL_SEQ, proto, key: 0, htonl(atomic_fetch_inc(&t->o_seqno)));
1069
1070 /* TooBig packet may have updated dst->dev's mtu */
1071 if (!t->parms.collect_md && dst && dst_mtu(dst) > dst->dev->mtu)
1072 dst->ops->update_pmtu(dst, NULL, skb, dst->dev->mtu, false);
1073
1074 err = ip6_tnl_xmit(skb, dev, dsfield, fl6: &fl6, encap_limit, pmtu: &mtu,
1075 NEXTHDR_GRE);
1076 if (err != 0) {
1077 /* XXX: send ICMP error even if DF is not set. */
1078 if (err == -EMSGSIZE) {
1079 if (skb->protocol == htons(ETH_P_IP))
1080 icmp_ndo_send(skb_in: skb, ICMP_DEST_UNREACH,
1081 ICMP_FRAG_NEEDED, htonl(mtu));
1082 else
1083 icmpv6_ndo_send(skb_in: skb, ICMPV6_PKT_TOOBIG, code: 0, info: mtu);
1084 }
1085
1086 goto tx_err;
1087 }
1088 return NETDEV_TX_OK;
1089
1090tx_err:
1091 if (!IS_ERR(ptr: tun_info))
1092 DEV_STATS_INC(dev, tx_errors);
1093 DEV_STATS_INC(dev, tx_dropped);
1094 kfree_skb(skb);
1095 return NETDEV_TX_OK;
1096}
1097
1098static void ip6gre_tnl_link_config_common(struct ip6_tnl *t)
1099{
1100 struct net_device *dev = t->dev;
1101 struct __ip6_tnl_parm *p = &t->parms;
1102 struct flowi6 *fl6 = &t->fl.u.ip6;
1103
1104 if (dev->type != ARPHRD_ETHER) {
1105 __dev_addr_set(dev, addr: &p->laddr, len: sizeof(struct in6_addr));
1106 memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr));
1107 }
1108
1109 /* Set up flowi template */
1110 fl6->saddr = p->laddr;
1111 fl6->daddr = p->raddr;
1112 fl6->flowi6_oif = p->link;
1113 fl6->flowlabel = 0;
1114 fl6->flowi6_proto = IPPROTO_GRE;
1115 fl6->fl6_gre_key = t->parms.o_key;
1116
1117 if (!(p->flags&IP6_TNL_F_USE_ORIG_TCLASS))
1118 fl6->flowlabel |= IPV6_TCLASS_MASK & p->flowinfo;
1119 if (!(p->flags&IP6_TNL_F_USE_ORIG_FLOWLABEL))
1120 fl6->flowlabel |= IPV6_FLOWLABEL_MASK & p->flowinfo;
1121
1122 p->flags &= ~(IP6_TNL_F_CAP_XMIT|IP6_TNL_F_CAP_RCV|IP6_TNL_F_CAP_PER_PACKET);
1123 p->flags |= ip6_tnl_get_cap(t, laddr: &p->laddr, raddr: &p->raddr);
1124
1125 if (p->flags&IP6_TNL_F_CAP_XMIT &&
1126 p->flags&IP6_TNL_F_CAP_RCV && dev->type != ARPHRD_ETHER)
1127 dev->flags |= IFF_POINTOPOINT;
1128 else
1129 dev->flags &= ~IFF_POINTOPOINT;
1130}
1131
1132static void ip6gre_tnl_link_config_route(struct ip6_tnl *t, int set_mtu,
1133 int t_hlen)
1134{
1135 const struct __ip6_tnl_parm *p = &t->parms;
1136 struct net_device *dev = t->dev;
1137
1138 if (p->flags & IP6_TNL_F_CAP_XMIT) {
1139 int strict = (ipv6_addr_type(addr: &p->raddr) &
1140 (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL));
1141
1142 struct rt6_info *rt = rt6_lookup(net: t->net,
1143 daddr: &p->raddr, saddr: &p->laddr,
1144 oif: p->link, NULL, flags: strict);
1145
1146 if (!rt)
1147 return;
1148
1149 if (rt->dst.dev) {
1150 unsigned short dst_len = rt->dst.dev->hard_header_len +
1151 t_hlen;
1152
1153 if (t->dev->header_ops)
1154 dev->hard_header_len = dst_len;
1155 else
1156 dev->needed_headroom = dst_len;
1157
1158 if (set_mtu) {
1159 int mtu = rt->dst.dev->mtu - t_hlen;
1160
1161 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1162 mtu -= 8;
1163 if (dev->type == ARPHRD_ETHER)
1164 mtu -= ETH_HLEN;
1165
1166 if (mtu < IPV6_MIN_MTU)
1167 mtu = IPV6_MIN_MTU;
1168 WRITE_ONCE(dev->mtu, mtu);
1169 }
1170 }
1171 ip6_rt_put(rt);
1172 }
1173}
1174
1175static int ip6gre_calc_hlen(struct ip6_tnl *tunnel)
1176{
1177 int t_hlen;
1178
1179 tunnel->tun_hlen = gre_calc_hlen(o_flags: tunnel->parms.o_flags);
1180 tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen;
1181
1182 t_hlen = tunnel->hlen + sizeof(struct ipv6hdr);
1183
1184 if (tunnel->dev->header_ops)
1185 tunnel->dev->hard_header_len = LL_MAX_HEADER + t_hlen;
1186 else
1187 tunnel->dev->needed_headroom = LL_MAX_HEADER + t_hlen;
1188
1189 return t_hlen;
1190}
1191
1192static void ip6gre_tnl_link_config(struct ip6_tnl *t, int set_mtu)
1193{
1194 ip6gre_tnl_link_config_common(t);
1195 ip6gre_tnl_link_config_route(t, set_mtu, t_hlen: ip6gre_calc_hlen(tunnel: t));
1196}
1197
1198static void ip6gre_tnl_copy_tnl_parm(struct ip6_tnl *t,
1199 const struct __ip6_tnl_parm *p)
1200{
1201 t->parms.laddr = p->laddr;
1202 t->parms.raddr = p->raddr;
1203 t->parms.flags = p->flags;
1204 t->parms.hop_limit = p->hop_limit;
1205 t->parms.encap_limit = p->encap_limit;
1206 t->parms.flowinfo = p->flowinfo;
1207 t->parms.link = p->link;
1208 t->parms.proto = p->proto;
1209 t->parms.i_key = p->i_key;
1210 t->parms.o_key = p->o_key;
1211 t->parms.i_flags = p->i_flags;
1212 t->parms.o_flags = p->o_flags;
1213 t->parms.fwmark = p->fwmark;
1214 t->parms.erspan_ver = p->erspan_ver;
1215 t->parms.index = p->index;
1216 t->parms.dir = p->dir;
1217 t->parms.hwid = p->hwid;
1218 dst_cache_reset(dst_cache: &t->dst_cache);
1219}
1220
1221static int ip6gre_tnl_change(struct ip6_tnl *t, const struct __ip6_tnl_parm *p,
1222 int set_mtu)
1223{
1224 ip6gre_tnl_copy_tnl_parm(t, p);
1225 ip6gre_tnl_link_config(t, set_mtu);
1226 return 0;
1227}
1228
1229static void ip6gre_tnl_parm_from_user(struct __ip6_tnl_parm *p,
1230 const struct ip6_tnl_parm2 *u)
1231{
1232 p->laddr = u->laddr;
1233 p->raddr = u->raddr;
1234 p->flags = u->flags;
1235 p->hop_limit = u->hop_limit;
1236 p->encap_limit = u->encap_limit;
1237 p->flowinfo = u->flowinfo;
1238 p->link = u->link;
1239 p->i_key = u->i_key;
1240 p->o_key = u->o_key;
1241 p->i_flags = gre_flags_to_tnl_flags(flags: u->i_flags);
1242 p->o_flags = gre_flags_to_tnl_flags(flags: u->o_flags);
1243 memcpy(p->name, u->name, sizeof(u->name));
1244}
1245
1246static void ip6gre_tnl_parm_to_user(struct ip6_tnl_parm2 *u,
1247 const struct __ip6_tnl_parm *p)
1248{
1249 u->proto = IPPROTO_GRE;
1250 u->laddr = p->laddr;
1251 u->raddr = p->raddr;
1252 u->flags = p->flags;
1253 u->hop_limit = p->hop_limit;
1254 u->encap_limit = p->encap_limit;
1255 u->flowinfo = p->flowinfo;
1256 u->link = p->link;
1257 u->i_key = p->i_key;
1258 u->o_key = p->o_key;
1259 u->i_flags = gre_tnl_flags_to_gre_flags(tflags: p->i_flags);
1260 u->o_flags = gre_tnl_flags_to_gre_flags(tflags: p->o_flags);
1261 memcpy(u->name, p->name, sizeof(u->name));
1262}
1263
1264static int ip6gre_tunnel_siocdevprivate(struct net_device *dev,
1265 struct ifreq *ifr, void __user *data,
1266 int cmd)
1267{
1268 int err = 0;
1269 struct ip6_tnl_parm2 p;
1270 struct __ip6_tnl_parm p1;
1271 struct ip6_tnl *t = netdev_priv(dev);
1272 struct net *net = t->net;
1273 struct ip6gre_net *ign = net_generic(net, id: ip6gre_net_id);
1274
1275 memset(&p1, 0, sizeof(p1));
1276
1277 switch (cmd) {
1278 case SIOCGETTUNNEL:
1279 if (dev == ign->fb_tunnel_dev) {
1280 if (copy_from_user(to: &p, from: data, n: sizeof(p))) {
1281 err = -EFAULT;
1282 break;
1283 }
1284 ip6gre_tnl_parm_from_user(p: &p1, u: &p);
1285 t = ip6gre_tunnel_locate(net, parms: &p1, create: 0);
1286 if (!t)
1287 t = netdev_priv(dev);
1288 }
1289 memset(&p, 0, sizeof(p));
1290 ip6gre_tnl_parm_to_user(u: &p, p: &t->parms);
1291 if (copy_to_user(to: data, from: &p, n: sizeof(p)))
1292 err = -EFAULT;
1293 break;
1294
1295 case SIOCADDTUNNEL:
1296 case SIOCCHGTUNNEL:
1297 err = -EPERM;
1298 if (!ns_capable(ns: net->user_ns, CAP_NET_ADMIN))
1299 goto done;
1300
1301 err = -EFAULT;
1302 if (copy_from_user(to: &p, from: data, n: sizeof(p)))
1303 goto done;
1304
1305 err = -EINVAL;
1306 if ((p.i_flags|p.o_flags)&(GRE_VERSION|GRE_ROUTING))
1307 goto done;
1308
1309 if (!(p.i_flags&GRE_KEY))
1310 p.i_key = 0;
1311 if (!(p.o_flags&GRE_KEY))
1312 p.o_key = 0;
1313
1314 ip6gre_tnl_parm_from_user(p: &p1, u: &p);
1315 t = ip6gre_tunnel_locate(net, parms: &p1, create: cmd == SIOCADDTUNNEL);
1316
1317 if (dev != ign->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) {
1318 if (t) {
1319 if (t->dev != dev) {
1320 err = -EEXIST;
1321 break;
1322 }
1323 } else {
1324 t = netdev_priv(dev);
1325
1326 ip6gre_tunnel_unlink(ign, t);
1327 synchronize_net();
1328 ip6gre_tnl_change(t, p: &p1, set_mtu: 1);
1329 ip6gre_tunnel_link(ign, t);
1330 netdev_state_change(dev);
1331 }
1332 }
1333
1334 if (t) {
1335 err = 0;
1336
1337 memset(&p, 0, sizeof(p));
1338 ip6gre_tnl_parm_to_user(u: &p, p: &t->parms);
1339 if (copy_to_user(to: data, from: &p, n: sizeof(p)))
1340 err = -EFAULT;
1341 } else
1342 err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
1343 break;
1344
1345 case SIOCDELTUNNEL:
1346 err = -EPERM;
1347 if (!ns_capable(ns: net->user_ns, CAP_NET_ADMIN))
1348 goto done;
1349
1350 if (dev == ign->fb_tunnel_dev) {
1351 err = -EFAULT;
1352 if (copy_from_user(to: &p, from: data, n: sizeof(p)))
1353 goto done;
1354 err = -ENOENT;
1355 ip6gre_tnl_parm_from_user(p: &p1, u: &p);
1356 t = ip6gre_tunnel_locate(net, parms: &p1, create: 0);
1357 if (!t)
1358 goto done;
1359 err = -EPERM;
1360 if (t == netdev_priv(dev: ign->fb_tunnel_dev))
1361 goto done;
1362 dev = t->dev;
1363 }
1364 unregister_netdevice(dev);
1365 err = 0;
1366 break;
1367
1368 default:
1369 err = -EINVAL;
1370 }
1371
1372done:
1373 return err;
1374}
1375
1376static int ip6gre_header(struct sk_buff *skb, struct net_device *dev,
1377 unsigned short type, const void *daddr,
1378 const void *saddr, unsigned int len)
1379{
1380 struct ip6_tnl *t = netdev_priv(dev);
1381 struct ipv6hdr *ipv6h;
1382 __be16 *p;
1383
1384 ipv6h = skb_push(skb, len: t->hlen + sizeof(*ipv6h));
1385 ip6_flow_hdr(hdr: ipv6h, tclass: 0, flowlabel: ip6_make_flowlabel(net: dev_net(dev), skb,
1386 flowlabel: t->fl.u.ip6.flowlabel,
1387 autolabel: true, fl6: &t->fl.u.ip6));
1388 ipv6h->hop_limit = t->parms.hop_limit;
1389 ipv6h->nexthdr = NEXTHDR_GRE;
1390 ipv6h->saddr = t->parms.laddr;
1391 ipv6h->daddr = t->parms.raddr;
1392
1393 p = (__be16 *)(ipv6h + 1);
1394 p[0] = t->parms.o_flags;
1395 p[1] = htons(type);
1396
1397 /*
1398 * Set the source hardware address.
1399 */
1400
1401 if (saddr)
1402 memcpy(&ipv6h->saddr, saddr, sizeof(struct in6_addr));
1403 if (daddr)
1404 memcpy(&ipv6h->daddr, daddr, sizeof(struct in6_addr));
1405 if (!ipv6_addr_any(a: &ipv6h->daddr))
1406 return t->hlen;
1407
1408 return -t->hlen;
1409}
1410
1411static const struct header_ops ip6gre_header_ops = {
1412 .create = ip6gre_header,
1413};
1414
1415static const struct net_device_ops ip6gre_netdev_ops = {
1416 .ndo_init = ip6gre_tunnel_init,
1417 .ndo_uninit = ip6gre_tunnel_uninit,
1418 .ndo_start_xmit = ip6gre_tunnel_xmit,
1419 .ndo_siocdevprivate = ip6gre_tunnel_siocdevprivate,
1420 .ndo_change_mtu = ip6_tnl_change_mtu,
1421 .ndo_get_stats64 = dev_get_tstats64,
1422 .ndo_get_iflink = ip6_tnl_get_iflink,
1423};
1424
1425static void ip6gre_dev_free(struct net_device *dev)
1426{
1427 struct ip6_tnl *t = netdev_priv(dev);
1428
1429 gro_cells_destroy(gcells: &t->gro_cells);
1430 dst_cache_destroy(dst_cache: &t->dst_cache);
1431 free_percpu(pdata: dev->tstats);
1432}
1433
1434static void ip6gre_tunnel_setup(struct net_device *dev)
1435{
1436 dev->netdev_ops = &ip6gre_netdev_ops;
1437 dev->needs_free_netdev = true;
1438 dev->priv_destructor = ip6gre_dev_free;
1439
1440 dev->type = ARPHRD_IP6GRE;
1441
1442 dev->flags |= IFF_NOARP;
1443 dev->addr_len = sizeof(struct in6_addr);
1444 netif_keep_dst(dev);
1445 /* This perm addr will be used as interface identifier by IPv6 */
1446 dev->addr_assign_type = NET_ADDR_RANDOM;
1447 eth_random_addr(addr: dev->perm_addr);
1448}
1449
1450#define GRE6_FEATURES (NETIF_F_SG | \
1451 NETIF_F_FRAGLIST | \
1452 NETIF_F_HIGHDMA | \
1453 NETIF_F_HW_CSUM)
1454
1455static void ip6gre_tnl_init_features(struct net_device *dev)
1456{
1457 struct ip6_tnl *nt = netdev_priv(dev);
1458 __be16 flags;
1459
1460 dev->features |= GRE6_FEATURES | NETIF_F_LLTX;
1461 dev->hw_features |= GRE6_FEATURES;
1462
1463 flags = nt->parms.o_flags;
1464
1465 /* TCP offload with GRE SEQ is not supported, nor can we support 2
1466 * levels of outer headers requiring an update.
1467 */
1468 if (flags & TUNNEL_SEQ)
1469 return;
1470 if (flags & TUNNEL_CSUM && nt->encap.type != TUNNEL_ENCAP_NONE)
1471 return;
1472
1473 dev->features |= NETIF_F_GSO_SOFTWARE;
1474 dev->hw_features |= NETIF_F_GSO_SOFTWARE;
1475}
1476
1477static int ip6gre_tunnel_init_common(struct net_device *dev)
1478{
1479 struct ip6_tnl *tunnel;
1480 int ret;
1481 int t_hlen;
1482
1483 tunnel = netdev_priv(dev);
1484
1485 tunnel->dev = dev;
1486 tunnel->net = dev_net(dev);
1487 strcpy(p: tunnel->parms.name, q: dev->name);
1488
1489 dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
1490 if (!dev->tstats)
1491 return -ENOMEM;
1492
1493 ret = dst_cache_init(dst_cache: &tunnel->dst_cache, GFP_KERNEL);
1494 if (ret)
1495 goto cleanup_alloc_pcpu_stats;
1496
1497 ret = gro_cells_init(gcells: &tunnel->gro_cells, dev);
1498 if (ret)
1499 goto cleanup_dst_cache_init;
1500
1501 t_hlen = ip6gre_calc_hlen(tunnel);
1502 dev->mtu = ETH_DATA_LEN - t_hlen;
1503 if (dev->type == ARPHRD_ETHER)
1504 dev->mtu -= ETH_HLEN;
1505 if (!(tunnel->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1506 dev->mtu -= 8;
1507
1508 if (tunnel->parms.collect_md) {
1509 netif_keep_dst(dev);
1510 }
1511 ip6gre_tnl_init_features(dev);
1512
1513 netdev_hold(dev, tracker: &tunnel->dev_tracker, GFP_KERNEL);
1514 return 0;
1515
1516cleanup_dst_cache_init:
1517 dst_cache_destroy(dst_cache: &tunnel->dst_cache);
1518cleanup_alloc_pcpu_stats:
1519 free_percpu(pdata: dev->tstats);
1520 dev->tstats = NULL;
1521 return ret;
1522}
1523
1524static int ip6gre_tunnel_init(struct net_device *dev)
1525{
1526 struct ip6_tnl *tunnel;
1527 int ret;
1528
1529 ret = ip6gre_tunnel_init_common(dev);
1530 if (ret)
1531 return ret;
1532
1533 tunnel = netdev_priv(dev);
1534
1535 if (tunnel->parms.collect_md)
1536 return 0;
1537
1538 __dev_addr_set(dev, addr: &tunnel->parms.laddr, len: sizeof(struct in6_addr));
1539 memcpy(dev->broadcast, &tunnel->parms.raddr, sizeof(struct in6_addr));
1540
1541 if (ipv6_addr_any(a: &tunnel->parms.raddr))
1542 dev->header_ops = &ip6gre_header_ops;
1543
1544 return 0;
1545}
1546
1547static void ip6gre_fb_tunnel_init(struct net_device *dev)
1548{
1549 struct ip6_tnl *tunnel = netdev_priv(dev);
1550
1551 tunnel->dev = dev;
1552 tunnel->net = dev_net(dev);
1553 strcpy(p: tunnel->parms.name, q: dev->name);
1554
1555 tunnel->hlen = sizeof(struct ipv6hdr) + 4;
1556}
1557
1558static struct inet6_protocol ip6gre_protocol __read_mostly = {
1559 .handler = gre_rcv,
1560 .err_handler = ip6gre_err,
1561 .flags = INET6_PROTO_FINAL,
1562};
1563
1564static void ip6gre_destroy_tunnels(struct net *net, struct list_head *head)
1565{
1566 struct ip6gre_net *ign = net_generic(net, id: ip6gre_net_id);
1567 struct net_device *dev, *aux;
1568 int prio;
1569
1570 for_each_netdev_safe(net, dev, aux)
1571 if (dev->rtnl_link_ops == &ip6gre_link_ops ||
1572 dev->rtnl_link_ops == &ip6gre_tap_ops ||
1573 dev->rtnl_link_ops == &ip6erspan_tap_ops)
1574 unregister_netdevice_queue(dev, head);
1575
1576 for (prio = 0; prio < 4; prio++) {
1577 int h;
1578 for (h = 0; h < IP6_GRE_HASH_SIZE; h++) {
1579 struct ip6_tnl *t;
1580
1581 t = rtnl_dereference(ign->tunnels[prio][h]);
1582
1583 while (t) {
1584 /* If dev is in the same netns, it has already
1585 * been added to the list by the previous loop.
1586 */
1587 if (!net_eq(net1: dev_net(dev: t->dev), net2: net))
1588 unregister_netdevice_queue(dev: t->dev,
1589 head);
1590 t = rtnl_dereference(t->next);
1591 }
1592 }
1593 }
1594}
1595
1596static int __net_init ip6gre_init_net(struct net *net)
1597{
1598 struct ip6gre_net *ign = net_generic(net, id: ip6gre_net_id);
1599 struct net_device *ndev;
1600 int err;
1601
1602 if (!net_has_fallback_tunnels(net))
1603 return 0;
1604 ndev = alloc_netdev(sizeof(struct ip6_tnl), "ip6gre0",
1605 NET_NAME_UNKNOWN, ip6gre_tunnel_setup);
1606 if (!ndev) {
1607 err = -ENOMEM;
1608 goto err_alloc_dev;
1609 }
1610 ign->fb_tunnel_dev = ndev;
1611 dev_net_set(dev: ign->fb_tunnel_dev, net);
1612 /* FB netdevice is special: we have one, and only one per netns.
1613 * Allowing to move it to another netns is clearly unsafe.
1614 */
1615 ign->fb_tunnel_dev->features |= NETIF_F_NETNS_LOCAL;
1616
1617
1618 ip6gre_fb_tunnel_init(dev: ign->fb_tunnel_dev);
1619 ign->fb_tunnel_dev->rtnl_link_ops = &ip6gre_link_ops;
1620
1621 err = register_netdev(dev: ign->fb_tunnel_dev);
1622 if (err)
1623 goto err_reg_dev;
1624
1625 rcu_assign_pointer(ign->tunnels_wc[0],
1626 netdev_priv(ign->fb_tunnel_dev));
1627 return 0;
1628
1629err_reg_dev:
1630 free_netdev(dev: ndev);
1631err_alloc_dev:
1632 return err;
1633}
1634
1635static void __net_exit ip6gre_exit_batch_net(struct list_head *net_list)
1636{
1637 struct net *net;
1638 LIST_HEAD(list);
1639
1640 rtnl_lock();
1641 list_for_each_entry(net, net_list, exit_list)
1642 ip6gre_destroy_tunnels(net, head: &list);
1643 unregister_netdevice_many(head: &list);
1644 rtnl_unlock();
1645}
1646
1647static struct pernet_operations ip6gre_net_ops = {
1648 .init = ip6gre_init_net,
1649 .exit_batch = ip6gre_exit_batch_net,
1650 .id = &ip6gre_net_id,
1651 .size = sizeof(struct ip6gre_net),
1652};
1653
1654static int ip6gre_tunnel_validate(struct nlattr *tb[], struct nlattr *data[],
1655 struct netlink_ext_ack *extack)
1656{
1657 __be16 flags;
1658
1659 if (!data)
1660 return 0;
1661
1662 flags = 0;
1663 if (data[IFLA_GRE_IFLAGS])
1664 flags |= nla_get_be16(nla: data[IFLA_GRE_IFLAGS]);
1665 if (data[IFLA_GRE_OFLAGS])
1666 flags |= nla_get_be16(nla: data[IFLA_GRE_OFLAGS]);
1667 if (flags & (GRE_VERSION|GRE_ROUTING))
1668 return -EINVAL;
1669
1670 return 0;
1671}
1672
1673static int ip6gre_tap_validate(struct nlattr *tb[], struct nlattr *data[],
1674 struct netlink_ext_ack *extack)
1675{
1676 struct in6_addr daddr;
1677
1678 if (tb[IFLA_ADDRESS]) {
1679 if (nla_len(nla: tb[IFLA_ADDRESS]) != ETH_ALEN)
1680 return -EINVAL;
1681 if (!is_valid_ether_addr(addr: nla_data(nla: tb[IFLA_ADDRESS])))
1682 return -EADDRNOTAVAIL;
1683 }
1684
1685 if (!data)
1686 goto out;
1687
1688 if (data[IFLA_GRE_REMOTE]) {
1689 daddr = nla_get_in6_addr(nla: data[IFLA_GRE_REMOTE]);
1690 if (ipv6_addr_any(a: &daddr))
1691 return -EINVAL;
1692 }
1693
1694out:
1695 return ip6gre_tunnel_validate(tb, data, extack);
1696}
1697
1698static int ip6erspan_tap_validate(struct nlattr *tb[], struct nlattr *data[],
1699 struct netlink_ext_ack *extack)
1700{
1701 __be16 flags = 0;
1702 int ret, ver = 0;
1703
1704 if (!data)
1705 return 0;
1706
1707 ret = ip6gre_tap_validate(tb, data, extack);
1708 if (ret)
1709 return ret;
1710
1711 /* ERSPAN should only have GRE sequence and key flag */
1712 if (data[IFLA_GRE_OFLAGS])
1713 flags |= nla_get_be16(nla: data[IFLA_GRE_OFLAGS]);
1714 if (data[IFLA_GRE_IFLAGS])
1715 flags |= nla_get_be16(nla: data[IFLA_GRE_IFLAGS]);
1716 if (!data[IFLA_GRE_COLLECT_METADATA] &&
1717 flags != (GRE_SEQ | GRE_KEY))
1718 return -EINVAL;
1719
1720 /* ERSPAN Session ID only has 10-bit. Since we reuse
1721 * 32-bit key field as ID, check it's range.
1722 */
1723 if (data[IFLA_GRE_IKEY] &&
1724 (ntohl(nla_get_be32(data[IFLA_GRE_IKEY])) & ~ID_MASK))
1725 return -EINVAL;
1726
1727 if (data[IFLA_GRE_OKEY] &&
1728 (ntohl(nla_get_be32(data[IFLA_GRE_OKEY])) & ~ID_MASK))
1729 return -EINVAL;
1730
1731 if (data[IFLA_GRE_ERSPAN_VER]) {
1732 ver = nla_get_u8(nla: data[IFLA_GRE_ERSPAN_VER]);
1733 if (ver != 1 && ver != 2)
1734 return -EINVAL;
1735 }
1736
1737 if (ver == 1) {
1738 if (data[IFLA_GRE_ERSPAN_INDEX]) {
1739 u32 index = nla_get_u32(nla: data[IFLA_GRE_ERSPAN_INDEX]);
1740
1741 if (index & ~INDEX_MASK)
1742 return -EINVAL;
1743 }
1744 } else if (ver == 2) {
1745 if (data[IFLA_GRE_ERSPAN_DIR]) {
1746 u16 dir = nla_get_u8(nla: data[IFLA_GRE_ERSPAN_DIR]);
1747
1748 if (dir & ~(DIR_MASK >> DIR_OFFSET))
1749 return -EINVAL;
1750 }
1751
1752 if (data[IFLA_GRE_ERSPAN_HWID]) {
1753 u16 hwid = nla_get_u16(nla: data[IFLA_GRE_ERSPAN_HWID]);
1754
1755 if (hwid & ~(HWID_MASK >> HWID_OFFSET))
1756 return -EINVAL;
1757 }
1758 }
1759
1760 return 0;
1761}
1762
1763static void ip6erspan_set_version(struct nlattr *data[],
1764 struct __ip6_tnl_parm *parms)
1765{
1766 if (!data)
1767 return;
1768
1769 parms->erspan_ver = 1;
1770 if (data[IFLA_GRE_ERSPAN_VER])
1771 parms->erspan_ver = nla_get_u8(nla: data[IFLA_GRE_ERSPAN_VER]);
1772
1773 if (parms->erspan_ver == 1) {
1774 if (data[IFLA_GRE_ERSPAN_INDEX])
1775 parms->index = nla_get_u32(nla: data[IFLA_GRE_ERSPAN_INDEX]);
1776 } else if (parms->erspan_ver == 2) {
1777 if (data[IFLA_GRE_ERSPAN_DIR])
1778 parms->dir = nla_get_u8(nla: data[IFLA_GRE_ERSPAN_DIR]);
1779 if (data[IFLA_GRE_ERSPAN_HWID])
1780 parms->hwid = nla_get_u16(nla: data[IFLA_GRE_ERSPAN_HWID]);
1781 }
1782}
1783
1784static void ip6gre_netlink_parms(struct nlattr *data[],
1785 struct __ip6_tnl_parm *parms)
1786{
1787 memset(parms, 0, sizeof(*parms));
1788
1789 if (!data)
1790 return;
1791
1792 if (data[IFLA_GRE_LINK])
1793 parms->link = nla_get_u32(nla: data[IFLA_GRE_LINK]);
1794
1795 if (data[IFLA_GRE_IFLAGS])
1796 parms->i_flags = gre_flags_to_tnl_flags(
1797 flags: nla_get_be16(nla: data[IFLA_GRE_IFLAGS]));
1798
1799 if (data[IFLA_GRE_OFLAGS])
1800 parms->o_flags = gre_flags_to_tnl_flags(
1801 flags: nla_get_be16(nla: data[IFLA_GRE_OFLAGS]));
1802
1803 if (data[IFLA_GRE_IKEY])
1804 parms->i_key = nla_get_be32(nla: data[IFLA_GRE_IKEY]);
1805
1806 if (data[IFLA_GRE_OKEY])
1807 parms->o_key = nla_get_be32(nla: data[IFLA_GRE_OKEY]);
1808
1809 if (data[IFLA_GRE_LOCAL])
1810 parms->laddr = nla_get_in6_addr(nla: data[IFLA_GRE_LOCAL]);
1811
1812 if (data[IFLA_GRE_REMOTE])
1813 parms->raddr = nla_get_in6_addr(nla: data[IFLA_GRE_REMOTE]);
1814
1815 if (data[IFLA_GRE_TTL])
1816 parms->hop_limit = nla_get_u8(nla: data[IFLA_GRE_TTL]);
1817
1818 if (data[IFLA_GRE_ENCAP_LIMIT])
1819 parms->encap_limit = nla_get_u8(nla: data[IFLA_GRE_ENCAP_LIMIT]);
1820
1821 if (data[IFLA_GRE_FLOWINFO])
1822 parms->flowinfo = nla_get_be32(nla: data[IFLA_GRE_FLOWINFO]);
1823
1824 if (data[IFLA_GRE_FLAGS])
1825 parms->flags = nla_get_u32(nla: data[IFLA_GRE_FLAGS]);
1826
1827 if (data[IFLA_GRE_FWMARK])
1828 parms->fwmark = nla_get_u32(nla: data[IFLA_GRE_FWMARK]);
1829
1830 if (data[IFLA_GRE_COLLECT_METADATA])
1831 parms->collect_md = true;
1832}
1833
1834static int ip6gre_tap_init(struct net_device *dev)
1835{
1836 int ret;
1837
1838 ret = ip6gre_tunnel_init_common(dev);
1839 if (ret)
1840 return ret;
1841
1842 dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1843
1844 return 0;
1845}
1846
1847static const struct net_device_ops ip6gre_tap_netdev_ops = {
1848 .ndo_init = ip6gre_tap_init,
1849 .ndo_uninit = ip6gre_tunnel_uninit,
1850 .ndo_start_xmit = ip6gre_tunnel_xmit,
1851 .ndo_set_mac_address = eth_mac_addr,
1852 .ndo_validate_addr = eth_validate_addr,
1853 .ndo_change_mtu = ip6_tnl_change_mtu,
1854 .ndo_get_stats64 = dev_get_tstats64,
1855 .ndo_get_iflink = ip6_tnl_get_iflink,
1856};
1857
1858static int ip6erspan_calc_hlen(struct ip6_tnl *tunnel)
1859{
1860 int t_hlen;
1861
1862 tunnel->tun_hlen = 8;
1863 tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen +
1864 erspan_hdr_len(version: tunnel->parms.erspan_ver);
1865
1866 t_hlen = tunnel->hlen + sizeof(struct ipv6hdr);
1867 tunnel->dev->needed_headroom = LL_MAX_HEADER + t_hlen;
1868 return t_hlen;
1869}
1870
1871static int ip6erspan_tap_init(struct net_device *dev)
1872{
1873 struct ip6_tnl *tunnel;
1874 int t_hlen;
1875 int ret;
1876
1877 tunnel = netdev_priv(dev);
1878
1879 tunnel->dev = dev;
1880 tunnel->net = dev_net(dev);
1881 strcpy(p: tunnel->parms.name, q: dev->name);
1882
1883 dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
1884 if (!dev->tstats)
1885 return -ENOMEM;
1886
1887 ret = dst_cache_init(dst_cache: &tunnel->dst_cache, GFP_KERNEL);
1888 if (ret)
1889 goto cleanup_alloc_pcpu_stats;
1890
1891 ret = gro_cells_init(gcells: &tunnel->gro_cells, dev);
1892 if (ret)
1893 goto cleanup_dst_cache_init;
1894
1895 t_hlen = ip6erspan_calc_hlen(tunnel);
1896 dev->mtu = ETH_DATA_LEN - t_hlen;
1897 if (dev->type == ARPHRD_ETHER)
1898 dev->mtu -= ETH_HLEN;
1899 if (!(tunnel->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1900 dev->mtu -= 8;
1901
1902 dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1903 ip6erspan_tnl_link_config(t: tunnel, set_mtu: 1);
1904
1905 netdev_hold(dev, tracker: &tunnel->dev_tracker, GFP_KERNEL);
1906 return 0;
1907
1908cleanup_dst_cache_init:
1909 dst_cache_destroy(dst_cache: &tunnel->dst_cache);
1910cleanup_alloc_pcpu_stats:
1911 free_percpu(pdata: dev->tstats);
1912 dev->tstats = NULL;
1913 return ret;
1914}
1915
1916static const struct net_device_ops ip6erspan_netdev_ops = {
1917 .ndo_init = ip6erspan_tap_init,
1918 .ndo_uninit = ip6erspan_tunnel_uninit,
1919 .ndo_start_xmit = ip6erspan_tunnel_xmit,
1920 .ndo_set_mac_address = eth_mac_addr,
1921 .ndo_validate_addr = eth_validate_addr,
1922 .ndo_change_mtu = ip6_tnl_change_mtu,
1923 .ndo_get_stats64 = dev_get_tstats64,
1924 .ndo_get_iflink = ip6_tnl_get_iflink,
1925};
1926
1927static void ip6gre_tap_setup(struct net_device *dev)
1928{
1929
1930 ether_setup(dev);
1931
1932 dev->max_mtu = 0;
1933 dev->netdev_ops = &ip6gre_tap_netdev_ops;
1934 dev->needs_free_netdev = true;
1935 dev->priv_destructor = ip6gre_dev_free;
1936
1937 dev->priv_flags &= ~IFF_TX_SKB_SHARING;
1938 dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1939 netif_keep_dst(dev);
1940}
1941
1942static bool ip6gre_netlink_encap_parms(struct nlattr *data[],
1943 struct ip_tunnel_encap *ipencap)
1944{
1945 bool ret = false;
1946
1947 memset(ipencap, 0, sizeof(*ipencap));
1948
1949 if (!data)
1950 return ret;
1951
1952 if (data[IFLA_GRE_ENCAP_TYPE]) {
1953 ret = true;
1954 ipencap->type = nla_get_u16(nla: data[IFLA_GRE_ENCAP_TYPE]);
1955 }
1956
1957 if (data[IFLA_GRE_ENCAP_FLAGS]) {
1958 ret = true;
1959 ipencap->flags = nla_get_u16(nla: data[IFLA_GRE_ENCAP_FLAGS]);
1960 }
1961
1962 if (data[IFLA_GRE_ENCAP_SPORT]) {
1963 ret = true;
1964 ipencap->sport = nla_get_be16(nla: data[IFLA_GRE_ENCAP_SPORT]);
1965 }
1966
1967 if (data[IFLA_GRE_ENCAP_DPORT]) {
1968 ret = true;
1969 ipencap->dport = nla_get_be16(nla: data[IFLA_GRE_ENCAP_DPORT]);
1970 }
1971
1972 return ret;
1973}
1974
1975static int ip6gre_newlink_common(struct net *src_net, struct net_device *dev,
1976 struct nlattr *tb[], struct nlattr *data[],
1977 struct netlink_ext_ack *extack)
1978{
1979 struct ip6_tnl *nt;
1980 struct ip_tunnel_encap ipencap;
1981 int err;
1982
1983 nt = netdev_priv(dev);
1984
1985 if (ip6gre_netlink_encap_parms(data, ipencap: &ipencap)) {
1986 int err = ip6_tnl_encap_setup(t: nt, ipencap: &ipencap);
1987
1988 if (err < 0)
1989 return err;
1990 }
1991
1992 if (dev->type == ARPHRD_ETHER && !tb[IFLA_ADDRESS])
1993 eth_hw_addr_random(dev);
1994
1995 nt->dev = dev;
1996 nt->net = dev_net(dev);
1997
1998 err = register_netdevice(dev);
1999 if (err)
2000 goto out;
2001
2002 if (tb[IFLA_MTU])
2003 ip6_tnl_change_mtu(dev, new_mtu: nla_get_u32(nla: tb[IFLA_MTU]));
2004
2005out:
2006 return err;
2007}
2008
2009static int ip6gre_newlink(struct net *src_net, struct net_device *dev,
2010 struct nlattr *tb[], struct nlattr *data[],
2011 struct netlink_ext_ack *extack)
2012{
2013 struct ip6_tnl *nt = netdev_priv(dev);
2014 struct net *net = dev_net(dev);
2015 struct ip6gre_net *ign;
2016 int err;
2017
2018 ip6gre_netlink_parms(data, parms: &nt->parms);
2019 ign = net_generic(net, id: ip6gre_net_id);
2020
2021 if (nt->parms.collect_md) {
2022 if (rtnl_dereference(ign->collect_md_tun))
2023 return -EEXIST;
2024 } else {
2025 if (ip6gre_tunnel_find(net, parms: &nt->parms, type: dev->type))
2026 return -EEXIST;
2027 }
2028
2029 err = ip6gre_newlink_common(src_net, dev, tb, data, extack);
2030 if (!err) {
2031 ip6gre_tnl_link_config(t: nt, set_mtu: !tb[IFLA_MTU]);
2032 ip6gre_tunnel_link_md(ign, t: nt);
2033 ip6gre_tunnel_link(ign: net_generic(net, id: ip6gre_net_id), t: nt);
2034 }
2035 return err;
2036}
2037
2038static struct ip6_tnl *
2039ip6gre_changelink_common(struct net_device *dev, struct nlattr *tb[],
2040 struct nlattr *data[], struct __ip6_tnl_parm *p_p,
2041 struct netlink_ext_ack *extack)
2042{
2043 struct ip6_tnl *t, *nt = netdev_priv(dev);
2044 struct net *net = nt->net;
2045 struct ip6gre_net *ign = net_generic(net, id: ip6gre_net_id);
2046 struct ip_tunnel_encap ipencap;
2047
2048 if (dev == ign->fb_tunnel_dev)
2049 return ERR_PTR(error: -EINVAL);
2050
2051 if (ip6gre_netlink_encap_parms(data, ipencap: &ipencap)) {
2052 int err = ip6_tnl_encap_setup(t: nt, ipencap: &ipencap);
2053
2054 if (err < 0)
2055 return ERR_PTR(error: err);
2056 }
2057
2058 ip6gre_netlink_parms(data, parms: p_p);
2059
2060 t = ip6gre_tunnel_locate(net, parms: p_p, create: 0);
2061
2062 if (t) {
2063 if (t->dev != dev)
2064 return ERR_PTR(error: -EEXIST);
2065 } else {
2066 t = nt;
2067 }
2068
2069 return t;
2070}
2071
2072static int ip6gre_changelink(struct net_device *dev, struct nlattr *tb[],
2073 struct nlattr *data[],
2074 struct netlink_ext_ack *extack)
2075{
2076 struct ip6_tnl *t = netdev_priv(dev);
2077 struct ip6gre_net *ign = net_generic(net: t->net, id: ip6gre_net_id);
2078 struct __ip6_tnl_parm p;
2079
2080 t = ip6gre_changelink_common(dev, tb, data, p_p: &p, extack);
2081 if (IS_ERR(ptr: t))
2082 return PTR_ERR(ptr: t);
2083
2084 ip6gre_tunnel_unlink_md(ign, t);
2085 ip6gre_tunnel_unlink(ign, t);
2086 ip6gre_tnl_change(t, p: &p, set_mtu: !tb[IFLA_MTU]);
2087 ip6gre_tunnel_link_md(ign, t);
2088 ip6gre_tunnel_link(ign, t);
2089 return 0;
2090}
2091
2092static void ip6gre_dellink(struct net_device *dev, struct list_head *head)
2093{
2094 struct net *net = dev_net(dev);
2095 struct ip6gre_net *ign = net_generic(net, id: ip6gre_net_id);
2096
2097 if (dev != ign->fb_tunnel_dev)
2098 unregister_netdevice_queue(dev, head);
2099}
2100
2101static size_t ip6gre_get_size(const struct net_device *dev)
2102{
2103 return
2104 /* IFLA_GRE_LINK */
2105 nla_total_size(payload: 4) +
2106 /* IFLA_GRE_IFLAGS */
2107 nla_total_size(payload: 2) +
2108 /* IFLA_GRE_OFLAGS */
2109 nla_total_size(payload: 2) +
2110 /* IFLA_GRE_IKEY */
2111 nla_total_size(payload: 4) +
2112 /* IFLA_GRE_OKEY */
2113 nla_total_size(payload: 4) +
2114 /* IFLA_GRE_LOCAL */
2115 nla_total_size(payload: sizeof(struct in6_addr)) +
2116 /* IFLA_GRE_REMOTE */
2117 nla_total_size(payload: sizeof(struct in6_addr)) +
2118 /* IFLA_GRE_TTL */
2119 nla_total_size(payload: 1) +
2120 /* IFLA_GRE_ENCAP_LIMIT */
2121 nla_total_size(payload: 1) +
2122 /* IFLA_GRE_FLOWINFO */
2123 nla_total_size(payload: 4) +
2124 /* IFLA_GRE_FLAGS */
2125 nla_total_size(payload: 4) +
2126 /* IFLA_GRE_ENCAP_TYPE */
2127 nla_total_size(payload: 2) +
2128 /* IFLA_GRE_ENCAP_FLAGS */
2129 nla_total_size(payload: 2) +
2130 /* IFLA_GRE_ENCAP_SPORT */
2131 nla_total_size(payload: 2) +
2132 /* IFLA_GRE_ENCAP_DPORT */
2133 nla_total_size(payload: 2) +
2134 /* IFLA_GRE_COLLECT_METADATA */
2135 nla_total_size(payload: 0) +
2136 /* IFLA_GRE_FWMARK */
2137 nla_total_size(payload: 4) +
2138 /* IFLA_GRE_ERSPAN_INDEX */
2139 nla_total_size(payload: 4) +
2140 0;
2141}
2142
2143static int ip6gre_fill_info(struct sk_buff *skb, const struct net_device *dev)
2144{
2145 struct ip6_tnl *t = netdev_priv(dev);
2146 struct __ip6_tnl_parm *p = &t->parms;
2147 __be16 o_flags = p->o_flags;
2148
2149 if (p->erspan_ver == 1 || p->erspan_ver == 2) {
2150 if (!p->collect_md)
2151 o_flags |= TUNNEL_KEY;
2152
2153 if (nla_put_u8(skb, attrtype: IFLA_GRE_ERSPAN_VER, value: p->erspan_ver))
2154 goto nla_put_failure;
2155
2156 if (p->erspan_ver == 1) {
2157 if (nla_put_u32(skb, attrtype: IFLA_GRE_ERSPAN_INDEX, value: p->index))
2158 goto nla_put_failure;
2159 } else {
2160 if (nla_put_u8(skb, attrtype: IFLA_GRE_ERSPAN_DIR, value: p->dir))
2161 goto nla_put_failure;
2162 if (nla_put_u16(skb, attrtype: IFLA_GRE_ERSPAN_HWID, value: p->hwid))
2163 goto nla_put_failure;
2164 }
2165 }
2166
2167 if (nla_put_u32(skb, attrtype: IFLA_GRE_LINK, value: p->link) ||
2168 nla_put_be16(skb, attrtype: IFLA_GRE_IFLAGS,
2169 value: gre_tnl_flags_to_gre_flags(tflags: p->i_flags)) ||
2170 nla_put_be16(skb, attrtype: IFLA_GRE_OFLAGS,
2171 value: gre_tnl_flags_to_gre_flags(tflags: o_flags)) ||
2172 nla_put_be32(skb, attrtype: IFLA_GRE_IKEY, value: p->i_key) ||
2173 nla_put_be32(skb, attrtype: IFLA_GRE_OKEY, value: p->o_key) ||
2174 nla_put_in6_addr(skb, attrtype: IFLA_GRE_LOCAL, addr: &p->laddr) ||
2175 nla_put_in6_addr(skb, attrtype: IFLA_GRE_REMOTE, addr: &p->raddr) ||
2176 nla_put_u8(skb, attrtype: IFLA_GRE_TTL, value: p->hop_limit) ||
2177 nla_put_u8(skb, attrtype: IFLA_GRE_ENCAP_LIMIT, value: p->encap_limit) ||
2178 nla_put_be32(skb, attrtype: IFLA_GRE_FLOWINFO, value: p->flowinfo) ||
2179 nla_put_u32(skb, attrtype: IFLA_GRE_FLAGS, value: p->flags) ||
2180 nla_put_u32(skb, attrtype: IFLA_GRE_FWMARK, value: p->fwmark))
2181 goto nla_put_failure;
2182
2183 if (nla_put_u16(skb, attrtype: IFLA_GRE_ENCAP_TYPE,
2184 value: t->encap.type) ||
2185 nla_put_be16(skb, attrtype: IFLA_GRE_ENCAP_SPORT,
2186 value: t->encap.sport) ||
2187 nla_put_be16(skb, attrtype: IFLA_GRE_ENCAP_DPORT,
2188 value: t->encap.dport) ||
2189 nla_put_u16(skb, attrtype: IFLA_GRE_ENCAP_FLAGS,
2190 value: t->encap.flags))
2191 goto nla_put_failure;
2192
2193 if (p->collect_md) {
2194 if (nla_put_flag(skb, attrtype: IFLA_GRE_COLLECT_METADATA))
2195 goto nla_put_failure;
2196 }
2197
2198 return 0;
2199
2200nla_put_failure:
2201 return -EMSGSIZE;
2202}
2203
2204static const struct nla_policy ip6gre_policy[IFLA_GRE_MAX + 1] = {
2205 [IFLA_GRE_LINK] = { .type = NLA_U32 },
2206 [IFLA_GRE_IFLAGS] = { .type = NLA_U16 },
2207 [IFLA_GRE_OFLAGS] = { .type = NLA_U16 },
2208 [IFLA_GRE_IKEY] = { .type = NLA_U32 },
2209 [IFLA_GRE_OKEY] = { .type = NLA_U32 },
2210 [IFLA_GRE_LOCAL] = { .len = sizeof_field(struct ipv6hdr, saddr) },
2211 [IFLA_GRE_REMOTE] = { .len = sizeof_field(struct ipv6hdr, daddr) },
2212 [IFLA_GRE_TTL] = { .type = NLA_U8 },
2213 [IFLA_GRE_ENCAP_LIMIT] = { .type = NLA_U8 },
2214 [IFLA_GRE_FLOWINFO] = { .type = NLA_U32 },
2215 [IFLA_GRE_FLAGS] = { .type = NLA_U32 },
2216 [IFLA_GRE_ENCAP_TYPE] = { .type = NLA_U16 },
2217 [IFLA_GRE_ENCAP_FLAGS] = { .type = NLA_U16 },
2218 [IFLA_GRE_ENCAP_SPORT] = { .type = NLA_U16 },
2219 [IFLA_GRE_ENCAP_DPORT] = { .type = NLA_U16 },
2220 [IFLA_GRE_COLLECT_METADATA] = { .type = NLA_FLAG },
2221 [IFLA_GRE_FWMARK] = { .type = NLA_U32 },
2222 [IFLA_GRE_ERSPAN_INDEX] = { .type = NLA_U32 },
2223 [IFLA_GRE_ERSPAN_VER] = { .type = NLA_U8 },
2224 [IFLA_GRE_ERSPAN_DIR] = { .type = NLA_U8 },
2225 [IFLA_GRE_ERSPAN_HWID] = { .type = NLA_U16 },
2226};
2227
2228static void ip6erspan_tap_setup(struct net_device *dev)
2229{
2230 ether_setup(dev);
2231
2232 dev->max_mtu = 0;
2233 dev->netdev_ops = &ip6erspan_netdev_ops;
2234 dev->needs_free_netdev = true;
2235 dev->priv_destructor = ip6gre_dev_free;
2236
2237 dev->priv_flags &= ~IFF_TX_SKB_SHARING;
2238 dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
2239 netif_keep_dst(dev);
2240}
2241
2242static int ip6erspan_newlink(struct net *src_net, struct net_device *dev,
2243 struct nlattr *tb[], struct nlattr *data[],
2244 struct netlink_ext_ack *extack)
2245{
2246 struct ip6_tnl *nt = netdev_priv(dev);
2247 struct net *net = dev_net(dev);
2248 struct ip6gre_net *ign;
2249 int err;
2250
2251 ip6gre_netlink_parms(data, parms: &nt->parms);
2252 ip6erspan_set_version(data, parms: &nt->parms);
2253 ign = net_generic(net, id: ip6gre_net_id);
2254
2255 if (nt->parms.collect_md) {
2256 if (rtnl_dereference(ign->collect_md_tun_erspan))
2257 return -EEXIST;
2258 } else {
2259 if (ip6gre_tunnel_find(net, parms: &nt->parms, type: dev->type))
2260 return -EEXIST;
2261 }
2262
2263 err = ip6gre_newlink_common(src_net, dev, tb, data, extack);
2264 if (!err) {
2265 ip6erspan_tnl_link_config(t: nt, set_mtu: !tb[IFLA_MTU]);
2266 ip6erspan_tunnel_link_md(ign, t: nt);
2267 ip6gre_tunnel_link(ign: net_generic(net, id: ip6gre_net_id), t: nt);
2268 }
2269 return err;
2270}
2271
2272static void ip6erspan_tnl_link_config(struct ip6_tnl *t, int set_mtu)
2273{
2274 ip6gre_tnl_link_config_common(t);
2275 ip6gre_tnl_link_config_route(t, set_mtu, t_hlen: ip6erspan_calc_hlen(tunnel: t));
2276}
2277
2278static int ip6erspan_tnl_change(struct ip6_tnl *t,
2279 const struct __ip6_tnl_parm *p, int set_mtu)
2280{
2281 ip6gre_tnl_copy_tnl_parm(t, p);
2282 ip6erspan_tnl_link_config(t, set_mtu);
2283 return 0;
2284}
2285
2286static int ip6erspan_changelink(struct net_device *dev, struct nlattr *tb[],
2287 struct nlattr *data[],
2288 struct netlink_ext_ack *extack)
2289{
2290 struct ip6gre_net *ign = net_generic(net: dev_net(dev), id: ip6gre_net_id);
2291 struct __ip6_tnl_parm p;
2292 struct ip6_tnl *t;
2293
2294 t = ip6gre_changelink_common(dev, tb, data, p_p: &p, extack);
2295 if (IS_ERR(ptr: t))
2296 return PTR_ERR(ptr: t);
2297
2298 ip6erspan_set_version(data, parms: &p);
2299 ip6gre_tunnel_unlink_md(ign, t);
2300 ip6gre_tunnel_unlink(ign, t);
2301 ip6erspan_tnl_change(t, p: &p, set_mtu: !tb[IFLA_MTU]);
2302 ip6erspan_tunnel_link_md(ign, t);
2303 ip6gre_tunnel_link(ign, t);
2304 return 0;
2305}
2306
2307static struct rtnl_link_ops ip6gre_link_ops __read_mostly = {
2308 .kind = "ip6gre",
2309 .maxtype = IFLA_GRE_MAX,
2310 .policy = ip6gre_policy,
2311 .priv_size = sizeof(struct ip6_tnl),
2312 .setup = ip6gre_tunnel_setup,
2313 .validate = ip6gre_tunnel_validate,
2314 .newlink = ip6gre_newlink,
2315 .changelink = ip6gre_changelink,
2316 .dellink = ip6gre_dellink,
2317 .get_size = ip6gre_get_size,
2318 .fill_info = ip6gre_fill_info,
2319 .get_link_net = ip6_tnl_get_link_net,
2320};
2321
2322static struct rtnl_link_ops ip6gre_tap_ops __read_mostly = {
2323 .kind = "ip6gretap",
2324 .maxtype = IFLA_GRE_MAX,
2325 .policy = ip6gre_policy,
2326 .priv_size = sizeof(struct ip6_tnl),
2327 .setup = ip6gre_tap_setup,
2328 .validate = ip6gre_tap_validate,
2329 .newlink = ip6gre_newlink,
2330 .changelink = ip6gre_changelink,
2331 .get_size = ip6gre_get_size,
2332 .fill_info = ip6gre_fill_info,
2333 .get_link_net = ip6_tnl_get_link_net,
2334};
2335
2336static struct rtnl_link_ops ip6erspan_tap_ops __read_mostly = {
2337 .kind = "ip6erspan",
2338 .maxtype = IFLA_GRE_MAX,
2339 .policy = ip6gre_policy,
2340 .priv_size = sizeof(struct ip6_tnl),
2341 .setup = ip6erspan_tap_setup,
2342 .validate = ip6erspan_tap_validate,
2343 .newlink = ip6erspan_newlink,
2344 .changelink = ip6erspan_changelink,
2345 .get_size = ip6gre_get_size,
2346 .fill_info = ip6gre_fill_info,
2347 .get_link_net = ip6_tnl_get_link_net,
2348};
2349
2350/*
2351 * And now the modules code and kernel interface.
2352 */
2353
2354static int __init ip6gre_init(void)
2355{
2356 int err;
2357
2358 pr_info("GRE over IPv6 tunneling driver\n");
2359
2360 err = register_pernet_device(&ip6gre_net_ops);
2361 if (err < 0)
2362 return err;
2363
2364 err = inet6_add_protocol(prot: &ip6gre_protocol, IPPROTO_GRE);
2365 if (err < 0) {
2366 pr_info("%s: can't add protocol\n", __func__);
2367 goto add_proto_failed;
2368 }
2369
2370 err = rtnl_link_register(ops: &ip6gre_link_ops);
2371 if (err < 0)
2372 goto rtnl_link_failed;
2373
2374 err = rtnl_link_register(ops: &ip6gre_tap_ops);
2375 if (err < 0)
2376 goto tap_ops_failed;
2377
2378 err = rtnl_link_register(ops: &ip6erspan_tap_ops);
2379 if (err < 0)
2380 goto erspan_link_failed;
2381
2382out:
2383 return err;
2384
2385erspan_link_failed:
2386 rtnl_link_unregister(ops: &ip6gre_tap_ops);
2387tap_ops_failed:
2388 rtnl_link_unregister(ops: &ip6gre_link_ops);
2389rtnl_link_failed:
2390 inet6_del_protocol(prot: &ip6gre_protocol, IPPROTO_GRE);
2391add_proto_failed:
2392 unregister_pernet_device(&ip6gre_net_ops);
2393 goto out;
2394}
2395
2396static void __exit ip6gre_fini(void)
2397{
2398 rtnl_link_unregister(ops: &ip6gre_tap_ops);
2399 rtnl_link_unregister(ops: &ip6gre_link_ops);
2400 rtnl_link_unregister(ops: &ip6erspan_tap_ops);
2401 inet6_del_protocol(prot: &ip6gre_protocol, IPPROTO_GRE);
2402 unregister_pernet_device(&ip6gre_net_ops);
2403}
2404
2405module_init(ip6gre_init);
2406module_exit(ip6gre_fini);
2407MODULE_LICENSE("GPL");
2408MODULE_AUTHOR("D. Kozlov (xeb@mail.ru)");
2409MODULE_DESCRIPTION("GRE over IPv6 tunneling device");
2410MODULE_ALIAS_RTNL_LINK("ip6gre");
2411MODULE_ALIAS_RTNL_LINK("ip6gretap");
2412MODULE_ALIAS_RTNL_LINK("ip6erspan");
2413MODULE_ALIAS_NETDEV("ip6gre0");
2414

source code of linux/net/ipv6/ip6_gre.c