xref: /openbmc/linux/net/ipv6/ip6_gre.c (revision 2c6467d2)
1 /*
2  *	GRE over IPv6 protocol decoder.
3  *
4  *	Authors: Dmitry Kozlov (xeb@mail.ru)
5  *
6  *	This program is free software; you can redistribute it and/or
7  *	modify it under the terms of the GNU General Public License
8  *	as published by the Free Software Foundation; either version
9  *	2 of the License, or (at your option) any later version.
10  *
11  */
12 
13 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
14 
15 #include <linux/capability.h>
16 #include <linux/module.h>
17 #include <linux/types.h>
18 #include <linux/kernel.h>
19 #include <linux/slab.h>
20 #include <linux/uaccess.h>
21 #include <linux/skbuff.h>
22 #include <linux/netdevice.h>
23 #include <linux/in.h>
24 #include <linux/tcp.h>
25 #include <linux/udp.h>
26 #include <linux/if_arp.h>
27 #include <linux/init.h>
28 #include <linux/in6.h>
29 #include <linux/inetdevice.h>
30 #include <linux/igmp.h>
31 #include <linux/netfilter_ipv4.h>
32 #include <linux/etherdevice.h>
33 #include <linux/if_ether.h>
34 #include <linux/hash.h>
35 #include <linux/if_tunnel.h>
36 #include <linux/ip6_tunnel.h>
37 
38 #include <net/sock.h>
39 #include <net/ip.h>
40 #include <net/ip_tunnels.h>
41 #include <net/icmp.h>
42 #include <net/protocol.h>
43 #include <net/addrconf.h>
44 #include <net/arp.h>
45 #include <net/checksum.h>
46 #include <net/dsfield.h>
47 #include <net/inet_ecn.h>
48 #include <net/xfrm.h>
49 #include <net/net_namespace.h>
50 #include <net/netns/generic.h>
51 #include <net/rtnetlink.h>
52 
53 #include <net/ipv6.h>
54 #include <net/ip6_fib.h>
55 #include <net/ip6_route.h>
56 #include <net/ip6_tunnel.h>
57 #include <net/gre.h>
58 #include <net/erspan.h>
59 #include <net/dst_metadata.h>
60 
61 
62 static bool log_ecn_error = true;
63 module_param(log_ecn_error, bool, 0644);
64 MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN");
65 
66 #define IP6_GRE_HASH_SIZE_SHIFT  5
67 #define IP6_GRE_HASH_SIZE (1 << IP6_GRE_HASH_SIZE_SHIFT)
68 
69 static unsigned int ip6gre_net_id __read_mostly;
70 struct ip6gre_net {
71 	struct ip6_tnl __rcu *tunnels[4][IP6_GRE_HASH_SIZE];
72 
73 	struct ip6_tnl __rcu *collect_md_tun;
74 	struct ip6_tnl __rcu *collect_md_tun_erspan;
75 	struct net_device *fb_tunnel_dev;
76 };
77 
78 static struct rtnl_link_ops ip6gre_link_ops __read_mostly;
79 static struct rtnl_link_ops ip6gre_tap_ops __read_mostly;
80 static struct rtnl_link_ops ip6erspan_tap_ops __read_mostly;
81 static int ip6gre_tunnel_init(struct net_device *dev);
82 static void ip6gre_tunnel_setup(struct net_device *dev);
83 static void ip6gre_tunnel_link(struct ip6gre_net *ign, struct ip6_tnl *t);
84 static void ip6gre_tnl_link_config(struct ip6_tnl *t, int set_mtu);
85 static void ip6erspan_tnl_link_config(struct ip6_tnl *t, int set_mtu);
86 
87 /* Tunnel hash table */
88 
89 /*
90    4 hash tables:
91 
92    3: (remote,local)
93    2: (remote,*)
94    1: (*,local)
95    0: (*,*)
96 
97    We require exact key match i.e. if a key is present in packet
98    it will match only tunnel with the same key; if it is not present,
99    it will match only keyless tunnel.
100 
101    All keysless packets, if not matched configured keyless tunnels
102    will match fallback tunnel.
103  */
104 
105 #define HASH_KEY(key) (((__force u32)key^((__force u32)key>>4))&(IP6_GRE_HASH_SIZE - 1))
106 static u32 HASH_ADDR(const struct in6_addr *addr)
107 {
108 	u32 hash = ipv6_addr_hash(addr);
109 
110 	return hash_32(hash, IP6_GRE_HASH_SIZE_SHIFT);
111 }
112 
113 #define tunnels_r_l	tunnels[3]
114 #define tunnels_r	tunnels[2]
115 #define tunnels_l	tunnels[1]
116 #define tunnels_wc	tunnels[0]
117 
118 /* Given src, dst and key, find appropriate for input tunnel. */
119 
120 static struct ip6_tnl *ip6gre_tunnel_lookup(struct net_device *dev,
121 		const struct in6_addr *remote, const struct in6_addr *local,
122 		__be32 key, __be16 gre_proto)
123 {
124 	struct net *net = dev_net(dev);
125 	int link = dev->ifindex;
126 	unsigned int h0 = HASH_ADDR(remote);
127 	unsigned int h1 = HASH_KEY(key);
128 	struct ip6_tnl *t, *cand = NULL;
129 	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
130 	int dev_type = (gre_proto == htons(ETH_P_TEB) ||
131 			gre_proto == htons(ETH_P_ERSPAN) ||
132 			gre_proto == htons(ETH_P_ERSPAN2)) ?
133 		       ARPHRD_ETHER : ARPHRD_IP6GRE;
134 	int score, cand_score = 4;
135 
136 	for_each_ip_tunnel_rcu(t, ign->tunnels_r_l[h0 ^ h1]) {
137 		if (!ipv6_addr_equal(local, &t->parms.laddr) ||
138 		    !ipv6_addr_equal(remote, &t->parms.raddr) ||
139 		    key != t->parms.i_key ||
140 		    !(t->dev->flags & IFF_UP))
141 			continue;
142 
143 		if (t->dev->type != ARPHRD_IP6GRE &&
144 		    t->dev->type != dev_type)
145 			continue;
146 
147 		score = 0;
148 		if (t->parms.link != link)
149 			score |= 1;
150 		if (t->dev->type != dev_type)
151 			score |= 2;
152 		if (score == 0)
153 			return t;
154 
155 		if (score < cand_score) {
156 			cand = t;
157 			cand_score = score;
158 		}
159 	}
160 
161 	for_each_ip_tunnel_rcu(t, ign->tunnels_r[h0 ^ h1]) {
162 		if (!ipv6_addr_equal(remote, &t->parms.raddr) ||
163 		    key != t->parms.i_key ||
164 		    !(t->dev->flags & IFF_UP))
165 			continue;
166 
167 		if (t->dev->type != ARPHRD_IP6GRE &&
168 		    t->dev->type != dev_type)
169 			continue;
170 
171 		score = 0;
172 		if (t->parms.link != link)
173 			score |= 1;
174 		if (t->dev->type != dev_type)
175 			score |= 2;
176 		if (score == 0)
177 			return t;
178 
179 		if (score < cand_score) {
180 			cand = t;
181 			cand_score = score;
182 		}
183 	}
184 
185 	for_each_ip_tunnel_rcu(t, ign->tunnels_l[h1]) {
186 		if ((!ipv6_addr_equal(local, &t->parms.laddr) &&
187 			  (!ipv6_addr_equal(local, &t->parms.raddr) ||
188 				 !ipv6_addr_is_multicast(local))) ||
189 		    key != t->parms.i_key ||
190 		    !(t->dev->flags & IFF_UP))
191 			continue;
192 
193 		if (t->dev->type != ARPHRD_IP6GRE &&
194 		    t->dev->type != dev_type)
195 			continue;
196 
197 		score = 0;
198 		if (t->parms.link != link)
199 			score |= 1;
200 		if (t->dev->type != dev_type)
201 			score |= 2;
202 		if (score == 0)
203 			return t;
204 
205 		if (score < cand_score) {
206 			cand = t;
207 			cand_score = score;
208 		}
209 	}
210 
211 	for_each_ip_tunnel_rcu(t, ign->tunnels_wc[h1]) {
212 		if (t->parms.i_key != key ||
213 		    !(t->dev->flags & IFF_UP))
214 			continue;
215 
216 		if (t->dev->type != ARPHRD_IP6GRE &&
217 		    t->dev->type != dev_type)
218 			continue;
219 
220 		score = 0;
221 		if (t->parms.link != link)
222 			score |= 1;
223 		if (t->dev->type != dev_type)
224 			score |= 2;
225 		if (score == 0)
226 			return t;
227 
228 		if (score < cand_score) {
229 			cand = t;
230 			cand_score = score;
231 		}
232 	}
233 
234 	if (cand)
235 		return cand;
236 
237 	if (gre_proto == htons(ETH_P_ERSPAN) ||
238 	    gre_proto == htons(ETH_P_ERSPAN2))
239 		t = rcu_dereference(ign->collect_md_tun_erspan);
240 	else
241 		t = rcu_dereference(ign->collect_md_tun);
242 
243 	if (t && t->dev->flags & IFF_UP)
244 		return t;
245 
246 	dev = ign->fb_tunnel_dev;
247 	if (dev && dev->flags & IFF_UP)
248 		return netdev_priv(dev);
249 
250 	return NULL;
251 }
252 
253 static struct ip6_tnl __rcu **__ip6gre_bucket(struct ip6gre_net *ign,
254 		const struct __ip6_tnl_parm *p)
255 {
256 	const struct in6_addr *remote = &p->raddr;
257 	const struct in6_addr *local = &p->laddr;
258 	unsigned int h = HASH_KEY(p->i_key);
259 	int prio = 0;
260 
261 	if (!ipv6_addr_any(local))
262 		prio |= 1;
263 	if (!ipv6_addr_any(remote) && !ipv6_addr_is_multicast(remote)) {
264 		prio |= 2;
265 		h ^= HASH_ADDR(remote);
266 	}
267 
268 	return &ign->tunnels[prio][h];
269 }
270 
271 static void ip6gre_tunnel_link_md(struct ip6gre_net *ign, struct ip6_tnl *t)
272 {
273 	if (t->parms.collect_md)
274 		rcu_assign_pointer(ign->collect_md_tun, t);
275 }
276 
277 static void ip6erspan_tunnel_link_md(struct ip6gre_net *ign, struct ip6_tnl *t)
278 {
279 	if (t->parms.collect_md)
280 		rcu_assign_pointer(ign->collect_md_tun_erspan, t);
281 }
282 
283 static void ip6gre_tunnel_unlink_md(struct ip6gre_net *ign, struct ip6_tnl *t)
284 {
285 	if (t->parms.collect_md)
286 		rcu_assign_pointer(ign->collect_md_tun, NULL);
287 }
288 
289 static void ip6erspan_tunnel_unlink_md(struct ip6gre_net *ign,
290 				       struct ip6_tnl *t)
291 {
292 	if (t->parms.collect_md)
293 		rcu_assign_pointer(ign->collect_md_tun_erspan, NULL);
294 }
295 
296 static inline struct ip6_tnl __rcu **ip6gre_bucket(struct ip6gre_net *ign,
297 		const struct ip6_tnl *t)
298 {
299 	return __ip6gre_bucket(ign, &t->parms);
300 }
301 
302 static void ip6gre_tunnel_link(struct ip6gre_net *ign, struct ip6_tnl *t)
303 {
304 	struct ip6_tnl __rcu **tp = ip6gre_bucket(ign, t);
305 
306 	rcu_assign_pointer(t->next, rtnl_dereference(*tp));
307 	rcu_assign_pointer(*tp, t);
308 }
309 
310 static void ip6gre_tunnel_unlink(struct ip6gre_net *ign, struct ip6_tnl *t)
311 {
312 	struct ip6_tnl __rcu **tp;
313 	struct ip6_tnl *iter;
314 
315 	for (tp = ip6gre_bucket(ign, t);
316 	     (iter = rtnl_dereference(*tp)) != NULL;
317 	     tp = &iter->next) {
318 		if (t == iter) {
319 			rcu_assign_pointer(*tp, t->next);
320 			break;
321 		}
322 	}
323 }
324 
325 static struct ip6_tnl *ip6gre_tunnel_find(struct net *net,
326 					   const struct __ip6_tnl_parm *parms,
327 					   int type)
328 {
329 	const struct in6_addr *remote = &parms->raddr;
330 	const struct in6_addr *local = &parms->laddr;
331 	__be32 key = parms->i_key;
332 	int link = parms->link;
333 	struct ip6_tnl *t;
334 	struct ip6_tnl __rcu **tp;
335 	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
336 
337 	for (tp = __ip6gre_bucket(ign, parms);
338 	     (t = rtnl_dereference(*tp)) != NULL;
339 	     tp = &t->next)
340 		if (ipv6_addr_equal(local, &t->parms.laddr) &&
341 		    ipv6_addr_equal(remote, &t->parms.raddr) &&
342 		    key == t->parms.i_key &&
343 		    link == t->parms.link &&
344 		    type == t->dev->type)
345 			break;
346 
347 	return t;
348 }
349 
350 static struct ip6_tnl *ip6gre_tunnel_locate(struct net *net,
351 		const struct __ip6_tnl_parm *parms, int create)
352 {
353 	struct ip6_tnl *t, *nt;
354 	struct net_device *dev;
355 	char name[IFNAMSIZ];
356 	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
357 
358 	t = ip6gre_tunnel_find(net, parms, ARPHRD_IP6GRE);
359 	if (t && create)
360 		return NULL;
361 	if (t || !create)
362 		return t;
363 
364 	if (parms->name[0]) {
365 		if (!dev_valid_name(parms->name))
366 			return NULL;
367 		strlcpy(name, parms->name, IFNAMSIZ);
368 	} else {
369 		strcpy(name, "ip6gre%d");
370 	}
371 	dev = alloc_netdev(sizeof(*t), name, NET_NAME_UNKNOWN,
372 			   ip6gre_tunnel_setup);
373 	if (!dev)
374 		return NULL;
375 
376 	dev_net_set(dev, net);
377 
378 	nt = netdev_priv(dev);
379 	nt->parms = *parms;
380 	dev->rtnl_link_ops = &ip6gre_link_ops;
381 
382 	nt->dev = dev;
383 	nt->net = dev_net(dev);
384 
385 	if (register_netdevice(dev) < 0)
386 		goto failed_free;
387 
388 	ip6gre_tnl_link_config(nt, 1);
389 
390 	/* Can use a lockless transmit, unless we generate output sequences */
391 	if (!(nt->parms.o_flags & TUNNEL_SEQ))
392 		dev->features |= NETIF_F_LLTX;
393 
394 	dev_hold(dev);
395 	ip6gre_tunnel_link(ign, nt);
396 	return nt;
397 
398 failed_free:
399 	free_netdev(dev);
400 	return NULL;
401 }
402 
403 static void ip6erspan_tunnel_uninit(struct net_device *dev)
404 {
405 	struct ip6_tnl *t = netdev_priv(dev);
406 	struct ip6gre_net *ign = net_generic(t->net, ip6gre_net_id);
407 
408 	ip6erspan_tunnel_unlink_md(ign, t);
409 	ip6gre_tunnel_unlink(ign, t);
410 	dst_cache_reset(&t->dst_cache);
411 	dev_put(dev);
412 }
413 
414 static void ip6gre_tunnel_uninit(struct net_device *dev)
415 {
416 	struct ip6_tnl *t = netdev_priv(dev);
417 	struct ip6gre_net *ign = net_generic(t->net, ip6gre_net_id);
418 
419 	ip6gre_tunnel_unlink_md(ign, t);
420 	ip6gre_tunnel_unlink(ign, t);
421 	dst_cache_reset(&t->dst_cache);
422 	dev_put(dev);
423 }
424 
425 
426 static int ip6gre_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
427 		       u8 type, u8 code, int offset, __be32 info)
428 {
429 	struct net *net = dev_net(skb->dev);
430 	const struct ipv6hdr *ipv6h;
431 	struct tnl_ptk_info tpi;
432 	struct ip6_tnl *t;
433 
434 	if (gre_parse_header(skb, &tpi, NULL, htons(ETH_P_IPV6),
435 			     offset) < 0)
436 		return -EINVAL;
437 
438 	ipv6h = (const struct ipv6hdr *)skb->data;
439 	t = ip6gre_tunnel_lookup(skb->dev, &ipv6h->daddr, &ipv6h->saddr,
440 				 tpi.key, tpi.proto);
441 	if (!t)
442 		return -ENOENT;
443 
444 	switch (type) {
445 		struct ipv6_tlv_tnl_enc_lim *tel;
446 		__u32 teli;
447 	case ICMPV6_DEST_UNREACH:
448 		net_dbg_ratelimited("%s: Path to destination invalid or inactive!\n",
449 				    t->parms.name);
450 		if (code != ICMPV6_PORT_UNREACH)
451 			break;
452 		return 0;
453 	case ICMPV6_TIME_EXCEED:
454 		if (code == ICMPV6_EXC_HOPLIMIT) {
455 			net_dbg_ratelimited("%s: Too small hop limit or routing loop in tunnel!\n",
456 					    t->parms.name);
457 			break;
458 		}
459 		return 0;
460 	case ICMPV6_PARAMPROB:
461 		teli = 0;
462 		if (code == ICMPV6_HDR_FIELD)
463 			teli = ip6_tnl_parse_tlv_enc_lim(skb, skb->data);
464 
465 		if (teli && teli == be32_to_cpu(info) - 2) {
466 			tel = (struct ipv6_tlv_tnl_enc_lim *) &skb->data[teli];
467 			if (tel->encap_limit == 0) {
468 				net_dbg_ratelimited("%s: Too small encapsulation limit or routing loop in tunnel!\n",
469 						    t->parms.name);
470 			}
471 		} else {
472 			net_dbg_ratelimited("%s: Recipient unable to parse tunneled packet!\n",
473 					    t->parms.name);
474 		}
475 		return 0;
476 	case ICMPV6_PKT_TOOBIG:
477 		ip6_update_pmtu(skb, net, info, 0, 0, sock_net_uid(net, NULL));
478 		return 0;
479 	case NDISC_REDIRECT:
480 		ip6_redirect(skb, net, skb->dev->ifindex, 0,
481 			     sock_net_uid(net, NULL));
482 		return 0;
483 	}
484 
485 	if (time_before(jiffies, t->err_time + IP6TUNNEL_ERR_TIMEO))
486 		t->err_count++;
487 	else
488 		t->err_count = 1;
489 	t->err_time = jiffies;
490 
491 	return 0;
492 }
493 
494 static int ip6gre_rcv(struct sk_buff *skb, const struct tnl_ptk_info *tpi)
495 {
496 	const struct ipv6hdr *ipv6h;
497 	struct ip6_tnl *tunnel;
498 
499 	ipv6h = ipv6_hdr(skb);
500 	tunnel = ip6gre_tunnel_lookup(skb->dev,
501 				      &ipv6h->saddr, &ipv6h->daddr, tpi->key,
502 				      tpi->proto);
503 	if (tunnel) {
504 		if (tunnel->parms.collect_md) {
505 			struct metadata_dst *tun_dst;
506 			__be64 tun_id;
507 			__be16 flags;
508 
509 			flags = tpi->flags;
510 			tun_id = key32_to_tunnel_id(tpi->key);
511 
512 			tun_dst = ipv6_tun_rx_dst(skb, flags, tun_id, 0);
513 			if (!tun_dst)
514 				return PACKET_REJECT;
515 
516 			ip6_tnl_rcv(tunnel, skb, tpi, tun_dst, log_ecn_error);
517 		} else {
518 			ip6_tnl_rcv(tunnel, skb, tpi, NULL, log_ecn_error);
519 		}
520 
521 		return PACKET_RCVD;
522 	}
523 
524 	return PACKET_REJECT;
525 }
526 
527 static int ip6erspan_rcv(struct sk_buff *skb, int gre_hdr_len,
528 			 struct tnl_ptk_info *tpi)
529 {
530 	struct erspan_base_hdr *ershdr;
531 	struct erspan_metadata *pkt_md;
532 	const struct ipv6hdr *ipv6h;
533 	struct erspan_md2 *md2;
534 	struct ip6_tnl *tunnel;
535 	u8 ver;
536 
537 	if (unlikely(!pskb_may_pull(skb, sizeof(*ershdr))))
538 		return PACKET_REJECT;
539 
540 	ipv6h = ipv6_hdr(skb);
541 	ershdr = (struct erspan_base_hdr *)skb->data;
542 	ver = ershdr->ver;
543 	tpi->key = cpu_to_be32(get_session_id(ershdr));
544 
545 	tunnel = ip6gre_tunnel_lookup(skb->dev,
546 				      &ipv6h->saddr, &ipv6h->daddr, tpi->key,
547 				      tpi->proto);
548 	if (tunnel) {
549 		int len = erspan_hdr_len(ver);
550 
551 		if (unlikely(!pskb_may_pull(skb, len)))
552 			return PACKET_REJECT;
553 
554 		ershdr = (struct erspan_base_hdr *)skb->data;
555 		pkt_md = (struct erspan_metadata *)(ershdr + 1);
556 
557 		if (__iptunnel_pull_header(skb, len,
558 					   htons(ETH_P_TEB),
559 					   false, false) < 0)
560 			return PACKET_REJECT;
561 
562 		if (tunnel->parms.collect_md) {
563 			struct metadata_dst *tun_dst;
564 			struct ip_tunnel_info *info;
565 			struct erspan_metadata *md;
566 			__be64 tun_id;
567 			__be16 flags;
568 
569 			tpi->flags |= TUNNEL_KEY;
570 			flags = tpi->flags;
571 			tun_id = key32_to_tunnel_id(tpi->key);
572 
573 			tun_dst = ipv6_tun_rx_dst(skb, flags, tun_id,
574 						  sizeof(*md));
575 			if (!tun_dst)
576 				return PACKET_REJECT;
577 
578 			info = &tun_dst->u.tun_info;
579 			md = ip_tunnel_info_opts(info);
580 			md->version = ver;
581 			md2 = &md->u.md2;
582 			memcpy(md2, pkt_md, ver == 1 ? ERSPAN_V1_MDSIZE :
583 						       ERSPAN_V2_MDSIZE);
584 			info->key.tun_flags |= TUNNEL_ERSPAN_OPT;
585 			info->options_len = sizeof(*md);
586 
587 			ip6_tnl_rcv(tunnel, skb, tpi, tun_dst, log_ecn_error);
588 
589 		} else {
590 			ip6_tnl_rcv(tunnel, skb, tpi, NULL, log_ecn_error);
591 		}
592 
593 		return PACKET_RCVD;
594 	}
595 
596 	return PACKET_REJECT;
597 }
598 
599 static int gre_rcv(struct sk_buff *skb)
600 {
601 	struct tnl_ptk_info tpi;
602 	bool csum_err = false;
603 	int hdr_len;
604 
605 	hdr_len = gre_parse_header(skb, &tpi, &csum_err, htons(ETH_P_IPV6), 0);
606 	if (hdr_len < 0)
607 		goto drop;
608 
609 	if (iptunnel_pull_header(skb, hdr_len, tpi.proto, false))
610 		goto drop;
611 
612 	if (unlikely(tpi.proto == htons(ETH_P_ERSPAN) ||
613 		     tpi.proto == htons(ETH_P_ERSPAN2))) {
614 		if (ip6erspan_rcv(skb, hdr_len, &tpi) == PACKET_RCVD)
615 			return 0;
616 		goto out;
617 	}
618 
619 	if (ip6gre_rcv(skb, &tpi) == PACKET_RCVD)
620 		return 0;
621 
622 out:
623 	icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0);
624 drop:
625 	kfree_skb(skb);
626 	return 0;
627 }
628 
629 static int gre_handle_offloads(struct sk_buff *skb, bool csum)
630 {
631 	return iptunnel_handle_offloads(skb,
632 					csum ? SKB_GSO_GRE_CSUM : SKB_GSO_GRE);
633 }
634 
635 static void prepare_ip6gre_xmit_ipv4(struct sk_buff *skb,
636 				     struct net_device *dev,
637 				     struct flowi6 *fl6, __u8 *dsfield,
638 				     int *encap_limit)
639 {
640 	const struct iphdr *iph = ip_hdr(skb);
641 	struct ip6_tnl *t = netdev_priv(dev);
642 
643 	if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
644 		*encap_limit = t->parms.encap_limit;
645 
646 	memcpy(fl6, &t->fl.u.ip6, sizeof(*fl6));
647 
648 	if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
649 		*dsfield = ipv4_get_dsfield(iph);
650 	else
651 		*dsfield = ip6_tclass(t->parms.flowinfo);
652 
653 	if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
654 		fl6->flowi6_mark = skb->mark;
655 	else
656 		fl6->flowi6_mark = t->parms.fwmark;
657 
658 	fl6->flowi6_uid = sock_net_uid(dev_net(dev), NULL);
659 }
660 
661 static int prepare_ip6gre_xmit_ipv6(struct sk_buff *skb,
662 				    struct net_device *dev,
663 				    struct flowi6 *fl6, __u8 *dsfield,
664 				    int *encap_limit)
665 {
666 	struct ipv6hdr *ipv6h = ipv6_hdr(skb);
667 	struct ip6_tnl *t = netdev_priv(dev);
668 	__u16 offset;
669 
670 	offset = ip6_tnl_parse_tlv_enc_lim(skb, skb_network_header(skb));
671 	/* ip6_tnl_parse_tlv_enc_lim() might have reallocated skb->head */
672 
673 	if (offset > 0) {
674 		struct ipv6_tlv_tnl_enc_lim *tel;
675 
676 		tel = (struct ipv6_tlv_tnl_enc_lim *)&skb_network_header(skb)[offset];
677 		if (tel->encap_limit == 0) {
678 			icmpv6_send(skb, ICMPV6_PARAMPROB,
679 				    ICMPV6_HDR_FIELD, offset + 2);
680 			return -1;
681 		}
682 		*encap_limit = tel->encap_limit - 1;
683 	} else if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) {
684 		*encap_limit = t->parms.encap_limit;
685 	}
686 
687 	memcpy(fl6, &t->fl.u.ip6, sizeof(*fl6));
688 
689 	if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
690 		*dsfield = ipv6_get_dsfield(ipv6h);
691 	else
692 		*dsfield = ip6_tclass(t->parms.flowinfo);
693 
694 	if (t->parms.flags & IP6_TNL_F_USE_ORIG_FLOWLABEL)
695 		fl6->flowlabel |= ip6_flowlabel(ipv6h);
696 
697 	if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
698 		fl6->flowi6_mark = skb->mark;
699 	else
700 		fl6->flowi6_mark = t->parms.fwmark;
701 
702 	fl6->flowi6_uid = sock_net_uid(dev_net(dev), NULL);
703 
704 	return 0;
705 }
706 
707 static netdev_tx_t __gre6_xmit(struct sk_buff *skb,
708 			       struct net_device *dev, __u8 dsfield,
709 			       struct flowi6 *fl6, int encap_limit,
710 			       __u32 *pmtu, __be16 proto)
711 {
712 	struct ip6_tnl *tunnel = netdev_priv(dev);
713 	__be16 protocol;
714 
715 	if (dev->type == ARPHRD_ETHER)
716 		IPCB(skb)->flags = 0;
717 
718 	if (dev->header_ops && dev->type == ARPHRD_IP6GRE)
719 		fl6->daddr = ((struct ipv6hdr *)skb->data)->daddr;
720 	else
721 		fl6->daddr = tunnel->parms.raddr;
722 
723 	if (skb_cow_head(skb, dev->needed_headroom ?: tunnel->hlen))
724 		return -ENOMEM;
725 
726 	/* Push GRE header. */
727 	protocol = (dev->type == ARPHRD_ETHER) ? htons(ETH_P_TEB) : proto;
728 
729 	if (tunnel->parms.collect_md) {
730 		struct ip_tunnel_info *tun_info;
731 		const struct ip_tunnel_key *key;
732 		__be16 flags;
733 
734 		tun_info = skb_tunnel_info(skb);
735 		if (unlikely(!tun_info ||
736 			     !(tun_info->mode & IP_TUNNEL_INFO_TX) ||
737 			     ip_tunnel_info_af(tun_info) != AF_INET6))
738 			return -EINVAL;
739 
740 		key = &tun_info->key;
741 		memset(fl6, 0, sizeof(*fl6));
742 		fl6->flowi6_proto = IPPROTO_GRE;
743 		fl6->daddr = key->u.ipv6.dst;
744 		fl6->flowlabel = key->label;
745 		fl6->flowi6_uid = sock_net_uid(dev_net(dev), NULL);
746 
747 		dsfield = key->tos;
748 		flags = key->tun_flags &
749 			(TUNNEL_CSUM | TUNNEL_KEY | TUNNEL_SEQ);
750 		tunnel->tun_hlen = gre_calc_hlen(flags);
751 
752 		gre_build_header(skb, tunnel->tun_hlen,
753 				 flags, protocol,
754 				 tunnel_id_to_key32(tun_info->key.tun_id),
755 				 (flags & TUNNEL_SEQ) ? htonl(tunnel->o_seqno++)
756 						      : 0);
757 
758 	} else {
759 		if (tunnel->parms.o_flags & TUNNEL_SEQ)
760 			tunnel->o_seqno++;
761 
762 		gre_build_header(skb, tunnel->tun_hlen, tunnel->parms.o_flags,
763 				 protocol, tunnel->parms.o_key,
764 				 htonl(tunnel->o_seqno));
765 	}
766 
767 	return ip6_tnl_xmit(skb, dev, dsfield, fl6, encap_limit, pmtu,
768 			    NEXTHDR_GRE);
769 }
770 
771 static inline int ip6gre_xmit_ipv4(struct sk_buff *skb, struct net_device *dev)
772 {
773 	struct ip6_tnl *t = netdev_priv(dev);
774 	int encap_limit = -1;
775 	struct flowi6 fl6;
776 	__u8 dsfield = 0;
777 	__u32 mtu;
778 	int err;
779 
780 	memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
781 
782 	if (!t->parms.collect_md)
783 		prepare_ip6gre_xmit_ipv4(skb, dev, &fl6,
784 					 &dsfield, &encap_limit);
785 
786 	err = gre_handle_offloads(skb, !!(t->parms.o_flags & TUNNEL_CSUM));
787 	if (err)
788 		return -1;
789 
790 	err = __gre6_xmit(skb, dev, dsfield, &fl6, encap_limit, &mtu,
791 			  skb->protocol);
792 	if (err != 0) {
793 		/* XXX: send ICMP error even if DF is not set. */
794 		if (err == -EMSGSIZE)
795 			icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
796 				  htonl(mtu));
797 		return -1;
798 	}
799 
800 	return 0;
801 }
802 
803 static inline int ip6gre_xmit_ipv6(struct sk_buff *skb, struct net_device *dev)
804 {
805 	struct ip6_tnl *t = netdev_priv(dev);
806 	struct ipv6hdr *ipv6h = ipv6_hdr(skb);
807 	int encap_limit = -1;
808 	struct flowi6 fl6;
809 	__u8 dsfield = 0;
810 	__u32 mtu;
811 	int err;
812 
813 	if (ipv6_addr_equal(&t->parms.raddr, &ipv6h->saddr))
814 		return -1;
815 
816 	if (!t->parms.collect_md &&
817 	    prepare_ip6gre_xmit_ipv6(skb, dev, &fl6, &dsfield, &encap_limit))
818 		return -1;
819 
820 	if (gre_handle_offloads(skb, !!(t->parms.o_flags & TUNNEL_CSUM)))
821 		return -1;
822 
823 	err = __gre6_xmit(skb, dev, dsfield, &fl6, encap_limit,
824 			  &mtu, skb->protocol);
825 	if (err != 0) {
826 		if (err == -EMSGSIZE)
827 			icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
828 		return -1;
829 	}
830 
831 	return 0;
832 }
833 
834 /**
835  * ip6gre_tnl_addr_conflict - compare packet addresses to tunnel's own
836  *   @t: the outgoing tunnel device
837  *   @hdr: IPv6 header from the incoming packet
838  *
839  * Description:
840  *   Avoid trivial tunneling loop by checking that tunnel exit-point
841  *   doesn't match source of incoming packet.
842  *
843  * Return:
844  *   1 if conflict,
845  *   0 else
846  **/
847 
848 static inline bool ip6gre_tnl_addr_conflict(const struct ip6_tnl *t,
849 	const struct ipv6hdr *hdr)
850 {
851 	return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr);
852 }
853 
854 static int ip6gre_xmit_other(struct sk_buff *skb, struct net_device *dev)
855 {
856 	struct ip6_tnl *t = netdev_priv(dev);
857 	int encap_limit = -1;
858 	struct flowi6 fl6;
859 	__u32 mtu;
860 	int err;
861 
862 	if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
863 		encap_limit = t->parms.encap_limit;
864 
865 	if (!t->parms.collect_md)
866 		memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6));
867 
868 	err = gre_handle_offloads(skb, !!(t->parms.o_flags & TUNNEL_CSUM));
869 	if (err)
870 		return err;
871 
872 	err = __gre6_xmit(skb, dev, 0, &fl6, encap_limit, &mtu, skb->protocol);
873 
874 	return err;
875 }
876 
877 static netdev_tx_t ip6gre_tunnel_xmit(struct sk_buff *skb,
878 	struct net_device *dev)
879 {
880 	struct ip6_tnl *t = netdev_priv(dev);
881 	struct net_device_stats *stats = &t->dev->stats;
882 	int ret;
883 
884 	if (!pskb_inet_may_pull(skb))
885 		goto tx_err;
886 
887 	if (!ip6_tnl_xmit_ctl(t, &t->parms.laddr, &t->parms.raddr))
888 		goto tx_err;
889 
890 	switch (skb->protocol) {
891 	case htons(ETH_P_IP):
892 		ret = ip6gre_xmit_ipv4(skb, dev);
893 		break;
894 	case htons(ETH_P_IPV6):
895 		ret = ip6gre_xmit_ipv6(skb, dev);
896 		break;
897 	default:
898 		ret = ip6gre_xmit_other(skb, dev);
899 		break;
900 	}
901 
902 	if (ret < 0)
903 		goto tx_err;
904 
905 	return NETDEV_TX_OK;
906 
907 tx_err:
908 	stats->tx_errors++;
909 	stats->tx_dropped++;
910 	kfree_skb(skb);
911 	return NETDEV_TX_OK;
912 }
913 
914 static netdev_tx_t ip6erspan_tunnel_xmit(struct sk_buff *skb,
915 					 struct net_device *dev)
916 {
917 	struct ip6_tnl *t = netdev_priv(dev);
918 	struct dst_entry *dst = skb_dst(skb);
919 	struct net_device_stats *stats;
920 	bool truncate = false;
921 	int encap_limit = -1;
922 	__u8 dsfield = false;
923 	struct flowi6 fl6;
924 	int err = -EINVAL;
925 	__u32 mtu;
926 	int nhoff;
927 	int thoff;
928 
929 	if (!pskb_inet_may_pull(skb))
930 		goto tx_err;
931 
932 	if (!ip6_tnl_xmit_ctl(t, &t->parms.laddr, &t->parms.raddr))
933 		goto tx_err;
934 
935 	if (gre_handle_offloads(skb, false))
936 		goto tx_err;
937 
938 	if (skb->len > dev->mtu + dev->hard_header_len) {
939 		pskb_trim(skb, dev->mtu + dev->hard_header_len);
940 		truncate = true;
941 	}
942 
943 	nhoff = skb_network_header(skb) - skb_mac_header(skb);
944 	if (skb->protocol == htons(ETH_P_IP) &&
945 	    (ntohs(ip_hdr(skb)->tot_len) > skb->len - nhoff))
946 		truncate = true;
947 
948 	thoff = skb_transport_header(skb) - skb_mac_header(skb);
949 	if (skb->protocol == htons(ETH_P_IPV6) &&
950 	    (ntohs(ipv6_hdr(skb)->payload_len) > skb->len - thoff))
951 		truncate = true;
952 
953 	if (skb_cow_head(skb, dev->needed_headroom ?: t->hlen))
954 		goto tx_err;
955 
956 	t->parms.o_flags &= ~TUNNEL_KEY;
957 	IPCB(skb)->flags = 0;
958 
959 	/* For collect_md mode, derive fl6 from the tunnel key,
960 	 * for native mode, call prepare_ip6gre_xmit_{ipv4,ipv6}.
961 	 */
962 	if (t->parms.collect_md) {
963 		struct ip_tunnel_info *tun_info;
964 		const struct ip_tunnel_key *key;
965 		struct erspan_metadata *md;
966 		__be32 tun_id;
967 
968 		tun_info = skb_tunnel_info(skb);
969 		if (unlikely(!tun_info ||
970 			     !(tun_info->mode & IP_TUNNEL_INFO_TX) ||
971 			     ip_tunnel_info_af(tun_info) != AF_INET6))
972 			return -EINVAL;
973 
974 		key = &tun_info->key;
975 		memset(&fl6, 0, sizeof(fl6));
976 		fl6.flowi6_proto = IPPROTO_GRE;
977 		fl6.daddr = key->u.ipv6.dst;
978 		fl6.flowlabel = key->label;
979 		fl6.flowi6_uid = sock_net_uid(dev_net(dev), NULL);
980 
981 		dsfield = key->tos;
982 		if (!(tun_info->key.tun_flags & TUNNEL_ERSPAN_OPT))
983 			goto tx_err;
984 		md = ip_tunnel_info_opts(tun_info);
985 		if (!md)
986 			goto tx_err;
987 
988 		tun_id = tunnel_id_to_key32(key->tun_id);
989 		if (md->version == 1) {
990 			erspan_build_header(skb,
991 					    ntohl(tun_id),
992 					    ntohl(md->u.index), truncate,
993 					    false);
994 		} else if (md->version == 2) {
995 			erspan_build_header_v2(skb,
996 					       ntohl(tun_id),
997 					       md->u.md2.dir,
998 					       get_hwid(&md->u.md2),
999 					       truncate, false);
1000 		} else {
1001 			goto tx_err;
1002 		}
1003 	} else {
1004 		switch (skb->protocol) {
1005 		case htons(ETH_P_IP):
1006 			memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
1007 			prepare_ip6gre_xmit_ipv4(skb, dev, &fl6,
1008 						 &dsfield, &encap_limit);
1009 			break;
1010 		case htons(ETH_P_IPV6):
1011 			if (ipv6_addr_equal(&t->parms.raddr, &ipv6_hdr(skb)->saddr))
1012 				goto tx_err;
1013 			if (prepare_ip6gre_xmit_ipv6(skb, dev, &fl6,
1014 						     &dsfield, &encap_limit))
1015 				goto tx_err;
1016 			break;
1017 		default:
1018 			memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6));
1019 			break;
1020 		}
1021 
1022 		if (t->parms.erspan_ver == 1)
1023 			erspan_build_header(skb, ntohl(t->parms.o_key),
1024 					    t->parms.index,
1025 					    truncate, false);
1026 		else if (t->parms.erspan_ver == 2)
1027 			erspan_build_header_v2(skb, ntohl(t->parms.o_key),
1028 					       t->parms.dir,
1029 					       t->parms.hwid,
1030 					       truncate, false);
1031 		else
1032 			goto tx_err;
1033 
1034 		fl6.daddr = t->parms.raddr;
1035 	}
1036 
1037 	/* Push GRE header. */
1038 	gre_build_header(skb, 8, TUNNEL_SEQ,
1039 			 htons(ETH_P_ERSPAN), 0, htonl(t->o_seqno++));
1040 
1041 	/* TooBig packet may have updated dst->dev's mtu */
1042 	if (!t->parms.collect_md && dst && dst_mtu(dst) > dst->dev->mtu)
1043 		dst->ops->update_pmtu(dst, NULL, skb, dst->dev->mtu);
1044 
1045 	err = ip6_tnl_xmit(skb, dev, dsfield, &fl6, encap_limit, &mtu,
1046 			   NEXTHDR_GRE);
1047 	if (err != 0) {
1048 		/* XXX: send ICMP error even if DF is not set. */
1049 		if (err == -EMSGSIZE) {
1050 			if (skb->protocol == htons(ETH_P_IP))
1051 				icmp_send(skb, ICMP_DEST_UNREACH,
1052 					  ICMP_FRAG_NEEDED, htonl(mtu));
1053 			else
1054 				icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
1055 		}
1056 
1057 		goto tx_err;
1058 	}
1059 	return NETDEV_TX_OK;
1060 
1061 tx_err:
1062 	stats = &t->dev->stats;
1063 	stats->tx_errors++;
1064 	stats->tx_dropped++;
1065 	kfree_skb(skb);
1066 	return NETDEV_TX_OK;
1067 }
1068 
1069 static void ip6gre_tnl_link_config_common(struct ip6_tnl *t)
1070 {
1071 	struct net_device *dev = t->dev;
1072 	struct __ip6_tnl_parm *p = &t->parms;
1073 	struct flowi6 *fl6 = &t->fl.u.ip6;
1074 
1075 	if (dev->type != ARPHRD_ETHER) {
1076 		memcpy(dev->dev_addr, &p->laddr, sizeof(struct in6_addr));
1077 		memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr));
1078 	}
1079 
1080 	/* Set up flowi template */
1081 	fl6->saddr = p->laddr;
1082 	fl6->daddr = p->raddr;
1083 	fl6->flowi6_oif = p->link;
1084 	fl6->flowlabel = 0;
1085 	fl6->flowi6_proto = IPPROTO_GRE;
1086 
1087 	if (!(p->flags&IP6_TNL_F_USE_ORIG_TCLASS))
1088 		fl6->flowlabel |= IPV6_TCLASS_MASK & p->flowinfo;
1089 	if (!(p->flags&IP6_TNL_F_USE_ORIG_FLOWLABEL))
1090 		fl6->flowlabel |= IPV6_FLOWLABEL_MASK & p->flowinfo;
1091 
1092 	p->flags &= ~(IP6_TNL_F_CAP_XMIT|IP6_TNL_F_CAP_RCV|IP6_TNL_F_CAP_PER_PACKET);
1093 	p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr);
1094 
1095 	if (p->flags&IP6_TNL_F_CAP_XMIT &&
1096 			p->flags&IP6_TNL_F_CAP_RCV && dev->type != ARPHRD_ETHER)
1097 		dev->flags |= IFF_POINTOPOINT;
1098 	else
1099 		dev->flags &= ~IFF_POINTOPOINT;
1100 }
1101 
1102 static void ip6gre_tnl_link_config_route(struct ip6_tnl *t, int set_mtu,
1103 					 int t_hlen)
1104 {
1105 	const struct __ip6_tnl_parm *p = &t->parms;
1106 	struct net_device *dev = t->dev;
1107 
1108 	if (p->flags & IP6_TNL_F_CAP_XMIT) {
1109 		int strict = (ipv6_addr_type(&p->raddr) &
1110 			      (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL));
1111 
1112 		struct rt6_info *rt = rt6_lookup(t->net,
1113 						 &p->raddr, &p->laddr,
1114 						 p->link, NULL, strict);
1115 
1116 		if (!rt)
1117 			return;
1118 
1119 		if (rt->dst.dev) {
1120 			dev->needed_headroom = rt->dst.dev->hard_header_len +
1121 					       t_hlen;
1122 
1123 			if (set_mtu) {
1124 				dev->mtu = rt->dst.dev->mtu - t_hlen;
1125 				if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1126 					dev->mtu -= 8;
1127 				if (dev->type == ARPHRD_ETHER)
1128 					dev->mtu -= ETH_HLEN;
1129 
1130 				if (dev->mtu < IPV6_MIN_MTU)
1131 					dev->mtu = IPV6_MIN_MTU;
1132 			}
1133 		}
1134 		ip6_rt_put(rt);
1135 	}
1136 }
1137 
1138 static int ip6gre_calc_hlen(struct ip6_tnl *tunnel)
1139 {
1140 	int t_hlen;
1141 
1142 	tunnel->tun_hlen = gre_calc_hlen(tunnel->parms.o_flags);
1143 	tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen;
1144 
1145 	t_hlen = tunnel->hlen + sizeof(struct ipv6hdr);
1146 	tunnel->dev->needed_headroom = LL_MAX_HEADER + t_hlen;
1147 	return t_hlen;
1148 }
1149 
1150 static void ip6gre_tnl_link_config(struct ip6_tnl *t, int set_mtu)
1151 {
1152 	ip6gre_tnl_link_config_common(t);
1153 	ip6gre_tnl_link_config_route(t, set_mtu, ip6gre_calc_hlen(t));
1154 }
1155 
1156 static void ip6gre_tnl_copy_tnl_parm(struct ip6_tnl *t,
1157 				     const struct __ip6_tnl_parm *p)
1158 {
1159 	t->parms.laddr = p->laddr;
1160 	t->parms.raddr = p->raddr;
1161 	t->parms.flags = p->flags;
1162 	t->parms.hop_limit = p->hop_limit;
1163 	t->parms.encap_limit = p->encap_limit;
1164 	t->parms.flowinfo = p->flowinfo;
1165 	t->parms.link = p->link;
1166 	t->parms.proto = p->proto;
1167 	t->parms.i_key = p->i_key;
1168 	t->parms.o_key = p->o_key;
1169 	t->parms.i_flags = p->i_flags;
1170 	t->parms.o_flags = p->o_flags;
1171 	t->parms.fwmark = p->fwmark;
1172 	dst_cache_reset(&t->dst_cache);
1173 }
1174 
1175 static int ip6gre_tnl_change(struct ip6_tnl *t, const struct __ip6_tnl_parm *p,
1176 			     int set_mtu)
1177 {
1178 	ip6gre_tnl_copy_tnl_parm(t, p);
1179 	ip6gre_tnl_link_config(t, set_mtu);
1180 	return 0;
1181 }
1182 
1183 static void ip6gre_tnl_parm_from_user(struct __ip6_tnl_parm *p,
1184 	const struct ip6_tnl_parm2 *u)
1185 {
1186 	p->laddr = u->laddr;
1187 	p->raddr = u->raddr;
1188 	p->flags = u->flags;
1189 	p->hop_limit = u->hop_limit;
1190 	p->encap_limit = u->encap_limit;
1191 	p->flowinfo = u->flowinfo;
1192 	p->link = u->link;
1193 	p->i_key = u->i_key;
1194 	p->o_key = u->o_key;
1195 	p->i_flags = gre_flags_to_tnl_flags(u->i_flags);
1196 	p->o_flags = gre_flags_to_tnl_flags(u->o_flags);
1197 	memcpy(p->name, u->name, sizeof(u->name));
1198 }
1199 
1200 static void ip6gre_tnl_parm_to_user(struct ip6_tnl_parm2 *u,
1201 	const struct __ip6_tnl_parm *p)
1202 {
1203 	u->proto = IPPROTO_GRE;
1204 	u->laddr = p->laddr;
1205 	u->raddr = p->raddr;
1206 	u->flags = p->flags;
1207 	u->hop_limit = p->hop_limit;
1208 	u->encap_limit = p->encap_limit;
1209 	u->flowinfo = p->flowinfo;
1210 	u->link = p->link;
1211 	u->i_key = p->i_key;
1212 	u->o_key = p->o_key;
1213 	u->i_flags = gre_tnl_flags_to_gre_flags(p->i_flags);
1214 	u->o_flags = gre_tnl_flags_to_gre_flags(p->o_flags);
1215 	memcpy(u->name, p->name, sizeof(u->name));
1216 }
1217 
1218 static int ip6gre_tunnel_ioctl(struct net_device *dev,
1219 	struct ifreq *ifr, int cmd)
1220 {
1221 	int err = 0;
1222 	struct ip6_tnl_parm2 p;
1223 	struct __ip6_tnl_parm p1;
1224 	struct ip6_tnl *t = netdev_priv(dev);
1225 	struct net *net = t->net;
1226 	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
1227 
1228 	memset(&p1, 0, sizeof(p1));
1229 
1230 	switch (cmd) {
1231 	case SIOCGETTUNNEL:
1232 		if (dev == ign->fb_tunnel_dev) {
1233 			if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) {
1234 				err = -EFAULT;
1235 				break;
1236 			}
1237 			ip6gre_tnl_parm_from_user(&p1, &p);
1238 			t = ip6gre_tunnel_locate(net, &p1, 0);
1239 			if (!t)
1240 				t = netdev_priv(dev);
1241 		}
1242 		memset(&p, 0, sizeof(p));
1243 		ip6gre_tnl_parm_to_user(&p, &t->parms);
1244 		if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
1245 			err = -EFAULT;
1246 		break;
1247 
1248 	case SIOCADDTUNNEL:
1249 	case SIOCCHGTUNNEL:
1250 		err = -EPERM;
1251 		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1252 			goto done;
1253 
1254 		err = -EFAULT;
1255 		if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
1256 			goto done;
1257 
1258 		err = -EINVAL;
1259 		if ((p.i_flags|p.o_flags)&(GRE_VERSION|GRE_ROUTING))
1260 			goto done;
1261 
1262 		if (!(p.i_flags&GRE_KEY))
1263 			p.i_key = 0;
1264 		if (!(p.o_flags&GRE_KEY))
1265 			p.o_key = 0;
1266 
1267 		ip6gre_tnl_parm_from_user(&p1, &p);
1268 		t = ip6gre_tunnel_locate(net, &p1, cmd == SIOCADDTUNNEL);
1269 
1270 		if (dev != ign->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) {
1271 			if (t) {
1272 				if (t->dev != dev) {
1273 					err = -EEXIST;
1274 					break;
1275 				}
1276 			} else {
1277 				t = netdev_priv(dev);
1278 
1279 				ip6gre_tunnel_unlink(ign, t);
1280 				synchronize_net();
1281 				ip6gre_tnl_change(t, &p1, 1);
1282 				ip6gre_tunnel_link(ign, t);
1283 				netdev_state_change(dev);
1284 			}
1285 		}
1286 
1287 		if (t) {
1288 			err = 0;
1289 
1290 			memset(&p, 0, sizeof(p));
1291 			ip6gre_tnl_parm_to_user(&p, &t->parms);
1292 			if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
1293 				err = -EFAULT;
1294 		} else
1295 			err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
1296 		break;
1297 
1298 	case SIOCDELTUNNEL:
1299 		err = -EPERM;
1300 		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1301 			goto done;
1302 
1303 		if (dev == ign->fb_tunnel_dev) {
1304 			err = -EFAULT;
1305 			if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
1306 				goto done;
1307 			err = -ENOENT;
1308 			ip6gre_tnl_parm_from_user(&p1, &p);
1309 			t = ip6gre_tunnel_locate(net, &p1, 0);
1310 			if (!t)
1311 				goto done;
1312 			err = -EPERM;
1313 			if (t == netdev_priv(ign->fb_tunnel_dev))
1314 				goto done;
1315 			dev = t->dev;
1316 		}
1317 		unregister_netdevice(dev);
1318 		err = 0;
1319 		break;
1320 
1321 	default:
1322 		err = -EINVAL;
1323 	}
1324 
1325 done:
1326 	return err;
1327 }
1328 
1329 static int ip6gre_header(struct sk_buff *skb, struct net_device *dev,
1330 			 unsigned short type, const void *daddr,
1331 			 const void *saddr, unsigned int len)
1332 {
1333 	struct ip6_tnl *t = netdev_priv(dev);
1334 	struct ipv6hdr *ipv6h;
1335 	__be16 *p;
1336 
1337 	ipv6h = skb_push(skb, t->hlen + sizeof(*ipv6h));
1338 	ip6_flow_hdr(ipv6h, 0, ip6_make_flowlabel(dev_net(dev), skb,
1339 						  t->fl.u.ip6.flowlabel,
1340 						  true, &t->fl.u.ip6));
1341 	ipv6h->hop_limit = t->parms.hop_limit;
1342 	ipv6h->nexthdr = NEXTHDR_GRE;
1343 	ipv6h->saddr = t->parms.laddr;
1344 	ipv6h->daddr = t->parms.raddr;
1345 
1346 	p = (__be16 *)(ipv6h + 1);
1347 	p[0] = t->parms.o_flags;
1348 	p[1] = htons(type);
1349 
1350 	/*
1351 	 *	Set the source hardware address.
1352 	 */
1353 
1354 	if (saddr)
1355 		memcpy(&ipv6h->saddr, saddr, sizeof(struct in6_addr));
1356 	if (daddr)
1357 		memcpy(&ipv6h->daddr, daddr, sizeof(struct in6_addr));
1358 	if (!ipv6_addr_any(&ipv6h->daddr))
1359 		return t->hlen;
1360 
1361 	return -t->hlen;
1362 }
1363 
1364 static const struct header_ops ip6gre_header_ops = {
1365 	.create	= ip6gre_header,
1366 };
1367 
1368 static const struct net_device_ops ip6gre_netdev_ops = {
1369 	.ndo_init		= ip6gre_tunnel_init,
1370 	.ndo_uninit		= ip6gre_tunnel_uninit,
1371 	.ndo_start_xmit		= ip6gre_tunnel_xmit,
1372 	.ndo_do_ioctl		= ip6gre_tunnel_ioctl,
1373 	.ndo_change_mtu		= ip6_tnl_change_mtu,
1374 	.ndo_get_stats64	= ip_tunnel_get_stats64,
1375 	.ndo_get_iflink		= ip6_tnl_get_iflink,
1376 };
1377 
1378 static void ip6gre_dev_free(struct net_device *dev)
1379 {
1380 	struct ip6_tnl *t = netdev_priv(dev);
1381 
1382 	gro_cells_destroy(&t->gro_cells);
1383 	dst_cache_destroy(&t->dst_cache);
1384 	free_percpu(dev->tstats);
1385 }
1386 
1387 static void ip6gre_tunnel_setup(struct net_device *dev)
1388 {
1389 	dev->netdev_ops = &ip6gre_netdev_ops;
1390 	dev->needs_free_netdev = true;
1391 	dev->priv_destructor = ip6gre_dev_free;
1392 
1393 	dev->type = ARPHRD_IP6GRE;
1394 
1395 	dev->flags |= IFF_NOARP;
1396 	dev->addr_len = sizeof(struct in6_addr);
1397 	netif_keep_dst(dev);
1398 	/* This perm addr will be used as interface identifier by IPv6 */
1399 	dev->addr_assign_type = NET_ADDR_RANDOM;
1400 	eth_random_addr(dev->perm_addr);
1401 }
1402 
1403 #define GRE6_FEATURES (NETIF_F_SG |		\
1404 		       NETIF_F_FRAGLIST |	\
1405 		       NETIF_F_HIGHDMA |	\
1406 		       NETIF_F_HW_CSUM)
1407 
1408 static void ip6gre_tnl_init_features(struct net_device *dev)
1409 {
1410 	struct ip6_tnl *nt = netdev_priv(dev);
1411 
1412 	dev->features		|= GRE6_FEATURES;
1413 	dev->hw_features	|= GRE6_FEATURES;
1414 
1415 	if (!(nt->parms.o_flags & TUNNEL_SEQ)) {
1416 		/* TCP offload with GRE SEQ is not supported, nor
1417 		 * can we support 2 levels of outer headers requiring
1418 		 * an update.
1419 		 */
1420 		if (!(nt->parms.o_flags & TUNNEL_CSUM) ||
1421 		    nt->encap.type == TUNNEL_ENCAP_NONE) {
1422 			dev->features    |= NETIF_F_GSO_SOFTWARE;
1423 			dev->hw_features |= NETIF_F_GSO_SOFTWARE;
1424 		}
1425 
1426 		/* Can use a lockless transmit, unless we generate
1427 		 * output sequences
1428 		 */
1429 		dev->features |= NETIF_F_LLTX;
1430 	}
1431 }
1432 
1433 static int ip6gre_tunnel_init_common(struct net_device *dev)
1434 {
1435 	struct ip6_tnl *tunnel;
1436 	int ret;
1437 	int t_hlen;
1438 
1439 	tunnel = netdev_priv(dev);
1440 
1441 	tunnel->dev = dev;
1442 	tunnel->net = dev_net(dev);
1443 	strcpy(tunnel->parms.name, dev->name);
1444 
1445 	dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
1446 	if (!dev->tstats)
1447 		return -ENOMEM;
1448 
1449 	ret = dst_cache_init(&tunnel->dst_cache, GFP_KERNEL);
1450 	if (ret)
1451 		goto cleanup_alloc_pcpu_stats;
1452 
1453 	ret = gro_cells_init(&tunnel->gro_cells, dev);
1454 	if (ret)
1455 		goto cleanup_dst_cache_init;
1456 
1457 	t_hlen = ip6gre_calc_hlen(tunnel);
1458 	dev->mtu = ETH_DATA_LEN - t_hlen;
1459 	if (dev->type == ARPHRD_ETHER)
1460 		dev->mtu -= ETH_HLEN;
1461 	if (!(tunnel->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1462 		dev->mtu -= 8;
1463 
1464 	if (tunnel->parms.collect_md) {
1465 		dev->features |= NETIF_F_NETNS_LOCAL;
1466 		netif_keep_dst(dev);
1467 	}
1468 	ip6gre_tnl_init_features(dev);
1469 
1470 	return 0;
1471 
1472 cleanup_dst_cache_init:
1473 	dst_cache_destroy(&tunnel->dst_cache);
1474 cleanup_alloc_pcpu_stats:
1475 	free_percpu(dev->tstats);
1476 	dev->tstats = NULL;
1477 	return ret;
1478 }
1479 
1480 static int ip6gre_tunnel_init(struct net_device *dev)
1481 {
1482 	struct ip6_tnl *tunnel;
1483 	int ret;
1484 
1485 	ret = ip6gre_tunnel_init_common(dev);
1486 	if (ret)
1487 		return ret;
1488 
1489 	tunnel = netdev_priv(dev);
1490 
1491 	if (tunnel->parms.collect_md)
1492 		return 0;
1493 
1494 	memcpy(dev->dev_addr, &tunnel->parms.laddr, sizeof(struct in6_addr));
1495 	memcpy(dev->broadcast, &tunnel->parms.raddr, sizeof(struct in6_addr));
1496 
1497 	if (ipv6_addr_any(&tunnel->parms.raddr))
1498 		dev->header_ops = &ip6gre_header_ops;
1499 
1500 	return 0;
1501 }
1502 
1503 static void ip6gre_fb_tunnel_init(struct net_device *dev)
1504 {
1505 	struct ip6_tnl *tunnel = netdev_priv(dev);
1506 
1507 	tunnel->dev = dev;
1508 	tunnel->net = dev_net(dev);
1509 	strcpy(tunnel->parms.name, dev->name);
1510 
1511 	tunnel->hlen		= sizeof(struct ipv6hdr) + 4;
1512 
1513 	dev_hold(dev);
1514 }
1515 
1516 static struct inet6_protocol ip6gre_protocol __read_mostly = {
1517 	.handler     = gre_rcv,
1518 	.err_handler = ip6gre_err,
1519 	.flags       = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
1520 };
1521 
1522 static void ip6gre_destroy_tunnels(struct net *net, struct list_head *head)
1523 {
1524 	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
1525 	struct net_device *dev, *aux;
1526 	int prio;
1527 
1528 	for_each_netdev_safe(net, dev, aux)
1529 		if (dev->rtnl_link_ops == &ip6gre_link_ops ||
1530 		    dev->rtnl_link_ops == &ip6gre_tap_ops ||
1531 		    dev->rtnl_link_ops == &ip6erspan_tap_ops)
1532 			unregister_netdevice_queue(dev, head);
1533 
1534 	for (prio = 0; prio < 4; prio++) {
1535 		int h;
1536 		for (h = 0; h < IP6_GRE_HASH_SIZE; h++) {
1537 			struct ip6_tnl *t;
1538 
1539 			t = rtnl_dereference(ign->tunnels[prio][h]);
1540 
1541 			while (t) {
1542 				/* If dev is in the same netns, it has already
1543 				 * been added to the list by the previous loop.
1544 				 */
1545 				if (!net_eq(dev_net(t->dev), net))
1546 					unregister_netdevice_queue(t->dev,
1547 								   head);
1548 				t = rtnl_dereference(t->next);
1549 			}
1550 		}
1551 	}
1552 }
1553 
1554 static int __net_init ip6gre_init_net(struct net *net)
1555 {
1556 	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
1557 	int err;
1558 
1559 	if (!net_has_fallback_tunnels(net))
1560 		return 0;
1561 	ign->fb_tunnel_dev = alloc_netdev(sizeof(struct ip6_tnl), "ip6gre0",
1562 					  NET_NAME_UNKNOWN,
1563 					  ip6gre_tunnel_setup);
1564 	if (!ign->fb_tunnel_dev) {
1565 		err = -ENOMEM;
1566 		goto err_alloc_dev;
1567 	}
1568 	dev_net_set(ign->fb_tunnel_dev, net);
1569 	/* FB netdevice is special: we have one, and only one per netns.
1570 	 * Allowing to move it to another netns is clearly unsafe.
1571 	 */
1572 	ign->fb_tunnel_dev->features |= NETIF_F_NETNS_LOCAL;
1573 
1574 
1575 	ip6gre_fb_tunnel_init(ign->fb_tunnel_dev);
1576 	ign->fb_tunnel_dev->rtnl_link_ops = &ip6gre_link_ops;
1577 
1578 	err = register_netdev(ign->fb_tunnel_dev);
1579 	if (err)
1580 		goto err_reg_dev;
1581 
1582 	rcu_assign_pointer(ign->tunnels_wc[0],
1583 			   netdev_priv(ign->fb_tunnel_dev));
1584 	return 0;
1585 
1586 err_reg_dev:
1587 	free_netdev(ign->fb_tunnel_dev);
1588 err_alloc_dev:
1589 	return err;
1590 }
1591 
1592 static void __net_exit ip6gre_exit_batch_net(struct list_head *net_list)
1593 {
1594 	struct net *net;
1595 	LIST_HEAD(list);
1596 
1597 	rtnl_lock();
1598 	list_for_each_entry(net, net_list, exit_list)
1599 		ip6gre_destroy_tunnels(net, &list);
1600 	unregister_netdevice_many(&list);
1601 	rtnl_unlock();
1602 }
1603 
1604 static struct pernet_operations ip6gre_net_ops = {
1605 	.init = ip6gre_init_net,
1606 	.exit_batch = ip6gre_exit_batch_net,
1607 	.id   = &ip6gre_net_id,
1608 	.size = sizeof(struct ip6gre_net),
1609 };
1610 
1611 static int ip6gre_tunnel_validate(struct nlattr *tb[], struct nlattr *data[],
1612 				  struct netlink_ext_ack *extack)
1613 {
1614 	__be16 flags;
1615 
1616 	if (!data)
1617 		return 0;
1618 
1619 	flags = 0;
1620 	if (data[IFLA_GRE_IFLAGS])
1621 		flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]);
1622 	if (data[IFLA_GRE_OFLAGS])
1623 		flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]);
1624 	if (flags & (GRE_VERSION|GRE_ROUTING))
1625 		return -EINVAL;
1626 
1627 	return 0;
1628 }
1629 
1630 static int ip6gre_tap_validate(struct nlattr *tb[], struct nlattr *data[],
1631 			       struct netlink_ext_ack *extack)
1632 {
1633 	struct in6_addr daddr;
1634 
1635 	if (tb[IFLA_ADDRESS]) {
1636 		if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
1637 			return -EINVAL;
1638 		if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
1639 			return -EADDRNOTAVAIL;
1640 	}
1641 
1642 	if (!data)
1643 		goto out;
1644 
1645 	if (data[IFLA_GRE_REMOTE]) {
1646 		daddr = nla_get_in6_addr(data[IFLA_GRE_REMOTE]);
1647 		if (ipv6_addr_any(&daddr))
1648 			return -EINVAL;
1649 	}
1650 
1651 out:
1652 	return ip6gre_tunnel_validate(tb, data, extack);
1653 }
1654 
1655 static int ip6erspan_tap_validate(struct nlattr *tb[], struct nlattr *data[],
1656 				  struct netlink_ext_ack *extack)
1657 {
1658 	__be16 flags = 0;
1659 	int ret, ver = 0;
1660 
1661 	if (!data)
1662 		return 0;
1663 
1664 	ret = ip6gre_tap_validate(tb, data, extack);
1665 	if (ret)
1666 		return ret;
1667 
1668 	/* ERSPAN should only have GRE sequence and key flag */
1669 	if (data[IFLA_GRE_OFLAGS])
1670 		flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]);
1671 	if (data[IFLA_GRE_IFLAGS])
1672 		flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]);
1673 	if (!data[IFLA_GRE_COLLECT_METADATA] &&
1674 	    flags != (GRE_SEQ | GRE_KEY))
1675 		return -EINVAL;
1676 
1677 	/* ERSPAN Session ID only has 10-bit. Since we reuse
1678 	 * 32-bit key field as ID, check it's range.
1679 	 */
1680 	if (data[IFLA_GRE_IKEY] &&
1681 	    (ntohl(nla_get_be32(data[IFLA_GRE_IKEY])) & ~ID_MASK))
1682 		return -EINVAL;
1683 
1684 	if (data[IFLA_GRE_OKEY] &&
1685 	    (ntohl(nla_get_be32(data[IFLA_GRE_OKEY])) & ~ID_MASK))
1686 		return -EINVAL;
1687 
1688 	if (data[IFLA_GRE_ERSPAN_VER]) {
1689 		ver = nla_get_u8(data[IFLA_GRE_ERSPAN_VER]);
1690 		if (ver != 1 && ver != 2)
1691 			return -EINVAL;
1692 	}
1693 
1694 	if (ver == 1) {
1695 		if (data[IFLA_GRE_ERSPAN_INDEX]) {
1696 			u32 index = nla_get_u32(data[IFLA_GRE_ERSPAN_INDEX]);
1697 
1698 			if (index & ~INDEX_MASK)
1699 				return -EINVAL;
1700 		}
1701 	} else if (ver == 2) {
1702 		if (data[IFLA_GRE_ERSPAN_DIR]) {
1703 			u16 dir = nla_get_u8(data[IFLA_GRE_ERSPAN_DIR]);
1704 
1705 			if (dir & ~(DIR_MASK >> DIR_OFFSET))
1706 				return -EINVAL;
1707 		}
1708 
1709 		if (data[IFLA_GRE_ERSPAN_HWID]) {
1710 			u16 hwid = nla_get_u16(data[IFLA_GRE_ERSPAN_HWID]);
1711 
1712 			if (hwid & ~(HWID_MASK >> HWID_OFFSET))
1713 				return -EINVAL;
1714 		}
1715 	}
1716 
1717 	return 0;
1718 }
1719 
1720 static void ip6gre_netlink_parms(struct nlattr *data[],
1721 				struct __ip6_tnl_parm *parms)
1722 {
1723 	memset(parms, 0, sizeof(*parms));
1724 
1725 	if (!data)
1726 		return;
1727 
1728 	if (data[IFLA_GRE_LINK])
1729 		parms->link = nla_get_u32(data[IFLA_GRE_LINK]);
1730 
1731 	if (data[IFLA_GRE_IFLAGS])
1732 		parms->i_flags = gre_flags_to_tnl_flags(
1733 				nla_get_be16(data[IFLA_GRE_IFLAGS]));
1734 
1735 	if (data[IFLA_GRE_OFLAGS])
1736 		parms->o_flags = gre_flags_to_tnl_flags(
1737 				nla_get_be16(data[IFLA_GRE_OFLAGS]));
1738 
1739 	if (data[IFLA_GRE_IKEY])
1740 		parms->i_key = nla_get_be32(data[IFLA_GRE_IKEY]);
1741 
1742 	if (data[IFLA_GRE_OKEY])
1743 		parms->o_key = nla_get_be32(data[IFLA_GRE_OKEY]);
1744 
1745 	if (data[IFLA_GRE_LOCAL])
1746 		parms->laddr = nla_get_in6_addr(data[IFLA_GRE_LOCAL]);
1747 
1748 	if (data[IFLA_GRE_REMOTE])
1749 		parms->raddr = nla_get_in6_addr(data[IFLA_GRE_REMOTE]);
1750 
1751 	if (data[IFLA_GRE_TTL])
1752 		parms->hop_limit = nla_get_u8(data[IFLA_GRE_TTL]);
1753 
1754 	if (data[IFLA_GRE_ENCAP_LIMIT])
1755 		parms->encap_limit = nla_get_u8(data[IFLA_GRE_ENCAP_LIMIT]);
1756 
1757 	if (data[IFLA_GRE_FLOWINFO])
1758 		parms->flowinfo = nla_get_be32(data[IFLA_GRE_FLOWINFO]);
1759 
1760 	if (data[IFLA_GRE_FLAGS])
1761 		parms->flags = nla_get_u32(data[IFLA_GRE_FLAGS]);
1762 
1763 	if (data[IFLA_GRE_FWMARK])
1764 		parms->fwmark = nla_get_u32(data[IFLA_GRE_FWMARK]);
1765 
1766 	if (data[IFLA_GRE_COLLECT_METADATA])
1767 		parms->collect_md = true;
1768 
1769 	parms->erspan_ver = 1;
1770 	if (data[IFLA_GRE_ERSPAN_VER])
1771 		parms->erspan_ver = nla_get_u8(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(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(data[IFLA_GRE_ERSPAN_DIR]);
1779 		if (data[IFLA_GRE_ERSPAN_HWID])
1780 			parms->hwid = nla_get_u16(data[IFLA_GRE_ERSPAN_HWID]);
1781 	}
1782 }
1783 
1784 static int ip6gre_tap_init(struct net_device *dev)
1785 {
1786 	int ret;
1787 
1788 	ret = ip6gre_tunnel_init_common(dev);
1789 	if (ret)
1790 		return ret;
1791 
1792 	dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1793 
1794 	return 0;
1795 }
1796 
1797 static const struct net_device_ops ip6gre_tap_netdev_ops = {
1798 	.ndo_init = ip6gre_tap_init,
1799 	.ndo_uninit = ip6gre_tunnel_uninit,
1800 	.ndo_start_xmit = ip6gre_tunnel_xmit,
1801 	.ndo_set_mac_address = eth_mac_addr,
1802 	.ndo_validate_addr = eth_validate_addr,
1803 	.ndo_change_mtu = ip6_tnl_change_mtu,
1804 	.ndo_get_stats64 = ip_tunnel_get_stats64,
1805 	.ndo_get_iflink = ip6_tnl_get_iflink,
1806 };
1807 
1808 static int ip6erspan_calc_hlen(struct ip6_tnl *tunnel)
1809 {
1810 	int t_hlen;
1811 
1812 	tunnel->tun_hlen = 8;
1813 	tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen +
1814 		       erspan_hdr_len(tunnel->parms.erspan_ver);
1815 
1816 	t_hlen = tunnel->hlen + sizeof(struct ipv6hdr);
1817 	tunnel->dev->needed_headroom = LL_MAX_HEADER + t_hlen;
1818 	return t_hlen;
1819 }
1820 
1821 static int ip6erspan_tap_init(struct net_device *dev)
1822 {
1823 	struct ip6_tnl *tunnel;
1824 	int t_hlen;
1825 	int ret;
1826 
1827 	tunnel = netdev_priv(dev);
1828 
1829 	tunnel->dev = dev;
1830 	tunnel->net = dev_net(dev);
1831 	strcpy(tunnel->parms.name, dev->name);
1832 
1833 	dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
1834 	if (!dev->tstats)
1835 		return -ENOMEM;
1836 
1837 	ret = dst_cache_init(&tunnel->dst_cache, GFP_KERNEL);
1838 	if (ret)
1839 		goto cleanup_alloc_pcpu_stats;
1840 
1841 	ret = gro_cells_init(&tunnel->gro_cells, dev);
1842 	if (ret)
1843 		goto cleanup_dst_cache_init;
1844 
1845 	t_hlen = ip6erspan_calc_hlen(tunnel);
1846 	dev->mtu = ETH_DATA_LEN - t_hlen;
1847 	if (dev->type == ARPHRD_ETHER)
1848 		dev->mtu -= ETH_HLEN;
1849 	if (!(tunnel->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1850 		dev->mtu -= 8;
1851 
1852 	dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1853 	ip6erspan_tnl_link_config(tunnel, 1);
1854 
1855 	return 0;
1856 
1857 cleanup_dst_cache_init:
1858 	dst_cache_destroy(&tunnel->dst_cache);
1859 cleanup_alloc_pcpu_stats:
1860 	free_percpu(dev->tstats);
1861 	dev->tstats = NULL;
1862 	return ret;
1863 }
1864 
1865 static const struct net_device_ops ip6erspan_netdev_ops = {
1866 	.ndo_init =		ip6erspan_tap_init,
1867 	.ndo_uninit =		ip6erspan_tunnel_uninit,
1868 	.ndo_start_xmit =	ip6erspan_tunnel_xmit,
1869 	.ndo_set_mac_address =	eth_mac_addr,
1870 	.ndo_validate_addr =	eth_validate_addr,
1871 	.ndo_change_mtu =	ip6_tnl_change_mtu,
1872 	.ndo_get_stats64 =	ip_tunnel_get_stats64,
1873 	.ndo_get_iflink =	ip6_tnl_get_iflink,
1874 };
1875 
1876 static void ip6gre_tap_setup(struct net_device *dev)
1877 {
1878 
1879 	ether_setup(dev);
1880 
1881 	dev->max_mtu = 0;
1882 	dev->netdev_ops = &ip6gre_tap_netdev_ops;
1883 	dev->needs_free_netdev = true;
1884 	dev->priv_destructor = ip6gre_dev_free;
1885 
1886 	dev->features |= NETIF_F_NETNS_LOCAL;
1887 	dev->priv_flags &= ~IFF_TX_SKB_SHARING;
1888 	dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1889 	netif_keep_dst(dev);
1890 }
1891 
1892 static bool ip6gre_netlink_encap_parms(struct nlattr *data[],
1893 				       struct ip_tunnel_encap *ipencap)
1894 {
1895 	bool ret = false;
1896 
1897 	memset(ipencap, 0, sizeof(*ipencap));
1898 
1899 	if (!data)
1900 		return ret;
1901 
1902 	if (data[IFLA_GRE_ENCAP_TYPE]) {
1903 		ret = true;
1904 		ipencap->type = nla_get_u16(data[IFLA_GRE_ENCAP_TYPE]);
1905 	}
1906 
1907 	if (data[IFLA_GRE_ENCAP_FLAGS]) {
1908 		ret = true;
1909 		ipencap->flags = nla_get_u16(data[IFLA_GRE_ENCAP_FLAGS]);
1910 	}
1911 
1912 	if (data[IFLA_GRE_ENCAP_SPORT]) {
1913 		ret = true;
1914 		ipencap->sport = nla_get_be16(data[IFLA_GRE_ENCAP_SPORT]);
1915 	}
1916 
1917 	if (data[IFLA_GRE_ENCAP_DPORT]) {
1918 		ret = true;
1919 		ipencap->dport = nla_get_be16(data[IFLA_GRE_ENCAP_DPORT]);
1920 	}
1921 
1922 	return ret;
1923 }
1924 
1925 static int ip6gre_newlink_common(struct net *src_net, struct net_device *dev,
1926 				 struct nlattr *tb[], struct nlattr *data[],
1927 				 struct netlink_ext_ack *extack)
1928 {
1929 	struct ip6_tnl *nt;
1930 	struct ip_tunnel_encap ipencap;
1931 	int err;
1932 
1933 	nt = netdev_priv(dev);
1934 
1935 	if (ip6gre_netlink_encap_parms(data, &ipencap)) {
1936 		int err = ip6_tnl_encap_setup(nt, &ipencap);
1937 
1938 		if (err < 0)
1939 			return err;
1940 	}
1941 
1942 	if (dev->type == ARPHRD_ETHER && !tb[IFLA_ADDRESS])
1943 		eth_hw_addr_random(dev);
1944 
1945 	nt->dev = dev;
1946 	nt->net = dev_net(dev);
1947 
1948 	err = register_netdevice(dev);
1949 	if (err)
1950 		goto out;
1951 
1952 	if (tb[IFLA_MTU])
1953 		ip6_tnl_change_mtu(dev, nla_get_u32(tb[IFLA_MTU]));
1954 
1955 	dev_hold(dev);
1956 
1957 out:
1958 	return err;
1959 }
1960 
1961 static int ip6gre_newlink(struct net *src_net, struct net_device *dev,
1962 			  struct nlattr *tb[], struct nlattr *data[],
1963 			  struct netlink_ext_ack *extack)
1964 {
1965 	struct ip6_tnl *nt = netdev_priv(dev);
1966 	struct net *net = dev_net(dev);
1967 	struct ip6gre_net *ign;
1968 	int err;
1969 
1970 	ip6gre_netlink_parms(data, &nt->parms);
1971 	ign = net_generic(net, ip6gre_net_id);
1972 
1973 	if (nt->parms.collect_md) {
1974 		if (rtnl_dereference(ign->collect_md_tun))
1975 			return -EEXIST;
1976 	} else {
1977 		if (ip6gre_tunnel_find(net, &nt->parms, dev->type))
1978 			return -EEXIST;
1979 	}
1980 
1981 	err = ip6gre_newlink_common(src_net, dev, tb, data, extack);
1982 	if (!err) {
1983 		ip6gre_tnl_link_config(nt, !tb[IFLA_MTU]);
1984 		ip6gre_tunnel_link_md(ign, nt);
1985 		ip6gre_tunnel_link(net_generic(net, ip6gre_net_id), nt);
1986 	}
1987 	return err;
1988 }
1989 
1990 static struct ip6_tnl *
1991 ip6gre_changelink_common(struct net_device *dev, struct nlattr *tb[],
1992 			 struct nlattr *data[], struct __ip6_tnl_parm *p_p,
1993 			 struct netlink_ext_ack *extack)
1994 {
1995 	struct ip6_tnl *t, *nt = netdev_priv(dev);
1996 	struct net *net = nt->net;
1997 	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
1998 	struct ip_tunnel_encap ipencap;
1999 
2000 	if (dev == ign->fb_tunnel_dev)
2001 		return ERR_PTR(-EINVAL);
2002 
2003 	if (ip6gre_netlink_encap_parms(data, &ipencap)) {
2004 		int err = ip6_tnl_encap_setup(nt, &ipencap);
2005 
2006 		if (err < 0)
2007 			return ERR_PTR(err);
2008 	}
2009 
2010 	ip6gre_netlink_parms(data, p_p);
2011 
2012 	t = ip6gre_tunnel_locate(net, p_p, 0);
2013 
2014 	if (t) {
2015 		if (t->dev != dev)
2016 			return ERR_PTR(-EEXIST);
2017 	} else {
2018 		t = nt;
2019 	}
2020 
2021 	return t;
2022 }
2023 
2024 static int ip6gre_changelink(struct net_device *dev, struct nlattr *tb[],
2025 			     struct nlattr *data[],
2026 			     struct netlink_ext_ack *extack)
2027 {
2028 	struct ip6gre_net *ign = net_generic(dev_net(dev), ip6gre_net_id);
2029 	struct __ip6_tnl_parm p;
2030 	struct ip6_tnl *t;
2031 
2032 	t = ip6gre_changelink_common(dev, tb, data, &p, extack);
2033 	if (IS_ERR(t))
2034 		return PTR_ERR(t);
2035 
2036 	ip6gre_tunnel_unlink_md(ign, t);
2037 	ip6gre_tunnel_unlink(ign, t);
2038 	ip6gre_tnl_change(t, &p, !tb[IFLA_MTU]);
2039 	ip6gre_tunnel_link_md(ign, t);
2040 	ip6gre_tunnel_link(ign, t);
2041 	return 0;
2042 }
2043 
2044 static void ip6gre_dellink(struct net_device *dev, struct list_head *head)
2045 {
2046 	struct net *net = dev_net(dev);
2047 	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
2048 
2049 	if (dev != ign->fb_tunnel_dev)
2050 		unregister_netdevice_queue(dev, head);
2051 }
2052 
2053 static size_t ip6gre_get_size(const struct net_device *dev)
2054 {
2055 	return
2056 		/* IFLA_GRE_LINK */
2057 		nla_total_size(4) +
2058 		/* IFLA_GRE_IFLAGS */
2059 		nla_total_size(2) +
2060 		/* IFLA_GRE_OFLAGS */
2061 		nla_total_size(2) +
2062 		/* IFLA_GRE_IKEY */
2063 		nla_total_size(4) +
2064 		/* IFLA_GRE_OKEY */
2065 		nla_total_size(4) +
2066 		/* IFLA_GRE_LOCAL */
2067 		nla_total_size(sizeof(struct in6_addr)) +
2068 		/* IFLA_GRE_REMOTE */
2069 		nla_total_size(sizeof(struct in6_addr)) +
2070 		/* IFLA_GRE_TTL */
2071 		nla_total_size(1) +
2072 		/* IFLA_GRE_ENCAP_LIMIT */
2073 		nla_total_size(1) +
2074 		/* IFLA_GRE_FLOWINFO */
2075 		nla_total_size(4) +
2076 		/* IFLA_GRE_FLAGS */
2077 		nla_total_size(4) +
2078 		/* IFLA_GRE_ENCAP_TYPE */
2079 		nla_total_size(2) +
2080 		/* IFLA_GRE_ENCAP_FLAGS */
2081 		nla_total_size(2) +
2082 		/* IFLA_GRE_ENCAP_SPORT */
2083 		nla_total_size(2) +
2084 		/* IFLA_GRE_ENCAP_DPORT */
2085 		nla_total_size(2) +
2086 		/* IFLA_GRE_COLLECT_METADATA */
2087 		nla_total_size(0) +
2088 		/* IFLA_GRE_FWMARK */
2089 		nla_total_size(4) +
2090 		/* IFLA_GRE_ERSPAN_INDEX */
2091 		nla_total_size(4) +
2092 		0;
2093 }
2094 
2095 static int ip6gre_fill_info(struct sk_buff *skb, const struct net_device *dev)
2096 {
2097 	struct ip6_tnl *t = netdev_priv(dev);
2098 	struct __ip6_tnl_parm *p = &t->parms;
2099 
2100 	if (nla_put_u32(skb, IFLA_GRE_LINK, p->link) ||
2101 	    nla_put_be16(skb, IFLA_GRE_IFLAGS,
2102 			 gre_tnl_flags_to_gre_flags(p->i_flags)) ||
2103 	    nla_put_be16(skb, IFLA_GRE_OFLAGS,
2104 			 gre_tnl_flags_to_gre_flags(p->o_flags)) ||
2105 	    nla_put_be32(skb, IFLA_GRE_IKEY, p->i_key) ||
2106 	    nla_put_be32(skb, IFLA_GRE_OKEY, p->o_key) ||
2107 	    nla_put_in6_addr(skb, IFLA_GRE_LOCAL, &p->laddr) ||
2108 	    nla_put_in6_addr(skb, IFLA_GRE_REMOTE, &p->raddr) ||
2109 	    nla_put_u8(skb, IFLA_GRE_TTL, p->hop_limit) ||
2110 	    nla_put_u8(skb, IFLA_GRE_ENCAP_LIMIT, p->encap_limit) ||
2111 	    nla_put_be32(skb, IFLA_GRE_FLOWINFO, p->flowinfo) ||
2112 	    nla_put_u32(skb, IFLA_GRE_FLAGS, p->flags) ||
2113 	    nla_put_u32(skb, IFLA_GRE_FWMARK, p->fwmark) ||
2114 	    nla_put_u32(skb, IFLA_GRE_ERSPAN_INDEX, p->index))
2115 		goto nla_put_failure;
2116 
2117 	if (nla_put_u16(skb, IFLA_GRE_ENCAP_TYPE,
2118 			t->encap.type) ||
2119 	    nla_put_be16(skb, IFLA_GRE_ENCAP_SPORT,
2120 			 t->encap.sport) ||
2121 	    nla_put_be16(skb, IFLA_GRE_ENCAP_DPORT,
2122 			 t->encap.dport) ||
2123 	    nla_put_u16(skb, IFLA_GRE_ENCAP_FLAGS,
2124 			t->encap.flags))
2125 		goto nla_put_failure;
2126 
2127 	if (p->collect_md) {
2128 		if (nla_put_flag(skb, IFLA_GRE_COLLECT_METADATA))
2129 			goto nla_put_failure;
2130 	}
2131 
2132 	if (nla_put_u8(skb, IFLA_GRE_ERSPAN_VER, p->erspan_ver))
2133 		goto nla_put_failure;
2134 
2135 	if (p->erspan_ver == 1) {
2136 		if (nla_put_u32(skb, IFLA_GRE_ERSPAN_INDEX, p->index))
2137 			goto nla_put_failure;
2138 	} else if (p->erspan_ver == 2) {
2139 		if (nla_put_u8(skb, IFLA_GRE_ERSPAN_DIR, p->dir))
2140 			goto nla_put_failure;
2141 		if (nla_put_u16(skb, IFLA_GRE_ERSPAN_HWID, p->hwid))
2142 			goto nla_put_failure;
2143 	}
2144 
2145 	return 0;
2146 
2147 nla_put_failure:
2148 	return -EMSGSIZE;
2149 }
2150 
2151 static const struct nla_policy ip6gre_policy[IFLA_GRE_MAX + 1] = {
2152 	[IFLA_GRE_LINK]        = { .type = NLA_U32 },
2153 	[IFLA_GRE_IFLAGS]      = { .type = NLA_U16 },
2154 	[IFLA_GRE_OFLAGS]      = { .type = NLA_U16 },
2155 	[IFLA_GRE_IKEY]        = { .type = NLA_U32 },
2156 	[IFLA_GRE_OKEY]        = { .type = NLA_U32 },
2157 	[IFLA_GRE_LOCAL]       = { .len = FIELD_SIZEOF(struct ipv6hdr, saddr) },
2158 	[IFLA_GRE_REMOTE]      = { .len = FIELD_SIZEOF(struct ipv6hdr, daddr) },
2159 	[IFLA_GRE_TTL]         = { .type = NLA_U8 },
2160 	[IFLA_GRE_ENCAP_LIMIT] = { .type = NLA_U8 },
2161 	[IFLA_GRE_FLOWINFO]    = { .type = NLA_U32 },
2162 	[IFLA_GRE_FLAGS]       = { .type = NLA_U32 },
2163 	[IFLA_GRE_ENCAP_TYPE]   = { .type = NLA_U16 },
2164 	[IFLA_GRE_ENCAP_FLAGS]  = { .type = NLA_U16 },
2165 	[IFLA_GRE_ENCAP_SPORT]  = { .type = NLA_U16 },
2166 	[IFLA_GRE_ENCAP_DPORT]  = { .type = NLA_U16 },
2167 	[IFLA_GRE_COLLECT_METADATA] = { .type = NLA_FLAG },
2168 	[IFLA_GRE_FWMARK]       = { .type = NLA_U32 },
2169 	[IFLA_GRE_ERSPAN_INDEX] = { .type = NLA_U32 },
2170 	[IFLA_GRE_ERSPAN_VER]	= { .type = NLA_U8 },
2171 	[IFLA_GRE_ERSPAN_DIR]	= { .type = NLA_U8 },
2172 	[IFLA_GRE_ERSPAN_HWID]	= { .type = NLA_U16 },
2173 };
2174 
2175 static void ip6erspan_tap_setup(struct net_device *dev)
2176 {
2177 	ether_setup(dev);
2178 
2179 	dev->netdev_ops = &ip6erspan_netdev_ops;
2180 	dev->needs_free_netdev = true;
2181 	dev->priv_destructor = ip6gre_dev_free;
2182 
2183 	dev->features |= NETIF_F_NETNS_LOCAL;
2184 	dev->priv_flags &= ~IFF_TX_SKB_SHARING;
2185 	dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
2186 	netif_keep_dst(dev);
2187 }
2188 
2189 static int ip6erspan_newlink(struct net *src_net, struct net_device *dev,
2190 			     struct nlattr *tb[], struct nlattr *data[],
2191 			     struct netlink_ext_ack *extack)
2192 {
2193 	struct ip6_tnl *nt = netdev_priv(dev);
2194 	struct net *net = dev_net(dev);
2195 	struct ip6gre_net *ign;
2196 	int err;
2197 
2198 	ip6gre_netlink_parms(data, &nt->parms);
2199 	ign = net_generic(net, ip6gre_net_id);
2200 
2201 	if (nt->parms.collect_md) {
2202 		if (rtnl_dereference(ign->collect_md_tun_erspan))
2203 			return -EEXIST;
2204 	} else {
2205 		if (ip6gre_tunnel_find(net, &nt->parms, dev->type))
2206 			return -EEXIST;
2207 	}
2208 
2209 	err = ip6gre_newlink_common(src_net, dev, tb, data, extack);
2210 	if (!err) {
2211 		ip6erspan_tnl_link_config(nt, !tb[IFLA_MTU]);
2212 		ip6erspan_tunnel_link_md(ign, nt);
2213 		ip6gre_tunnel_link(net_generic(net, ip6gre_net_id), nt);
2214 	}
2215 	return err;
2216 }
2217 
2218 static void ip6erspan_tnl_link_config(struct ip6_tnl *t, int set_mtu)
2219 {
2220 	ip6gre_tnl_link_config_common(t);
2221 	ip6gre_tnl_link_config_route(t, set_mtu, ip6erspan_calc_hlen(t));
2222 }
2223 
2224 static int ip6erspan_tnl_change(struct ip6_tnl *t,
2225 				const struct __ip6_tnl_parm *p, int set_mtu)
2226 {
2227 	ip6gre_tnl_copy_tnl_parm(t, p);
2228 	ip6erspan_tnl_link_config(t, set_mtu);
2229 	return 0;
2230 }
2231 
2232 static int ip6erspan_changelink(struct net_device *dev, struct nlattr *tb[],
2233 				struct nlattr *data[],
2234 				struct netlink_ext_ack *extack)
2235 {
2236 	struct ip6gre_net *ign = net_generic(dev_net(dev), ip6gre_net_id);
2237 	struct __ip6_tnl_parm p;
2238 	struct ip6_tnl *t;
2239 
2240 	t = ip6gre_changelink_common(dev, tb, data, &p, extack);
2241 	if (IS_ERR(t))
2242 		return PTR_ERR(t);
2243 
2244 	ip6gre_tunnel_unlink_md(ign, t);
2245 	ip6gre_tunnel_unlink(ign, t);
2246 	ip6erspan_tnl_change(t, &p, !tb[IFLA_MTU]);
2247 	ip6erspan_tunnel_link_md(ign, t);
2248 	ip6gre_tunnel_link(ign, t);
2249 	return 0;
2250 }
2251 
2252 static struct rtnl_link_ops ip6gre_link_ops __read_mostly = {
2253 	.kind		= "ip6gre",
2254 	.maxtype	= IFLA_GRE_MAX,
2255 	.policy		= ip6gre_policy,
2256 	.priv_size	= sizeof(struct ip6_tnl),
2257 	.setup		= ip6gre_tunnel_setup,
2258 	.validate	= ip6gre_tunnel_validate,
2259 	.newlink	= ip6gre_newlink,
2260 	.changelink	= ip6gre_changelink,
2261 	.dellink	= ip6gre_dellink,
2262 	.get_size	= ip6gre_get_size,
2263 	.fill_info	= ip6gre_fill_info,
2264 	.get_link_net	= ip6_tnl_get_link_net,
2265 };
2266 
2267 static struct rtnl_link_ops ip6gre_tap_ops __read_mostly = {
2268 	.kind		= "ip6gretap",
2269 	.maxtype	= IFLA_GRE_MAX,
2270 	.policy		= ip6gre_policy,
2271 	.priv_size	= sizeof(struct ip6_tnl),
2272 	.setup		= ip6gre_tap_setup,
2273 	.validate	= ip6gre_tap_validate,
2274 	.newlink	= ip6gre_newlink,
2275 	.changelink	= ip6gre_changelink,
2276 	.get_size	= ip6gre_get_size,
2277 	.fill_info	= ip6gre_fill_info,
2278 	.get_link_net	= ip6_tnl_get_link_net,
2279 };
2280 
2281 static struct rtnl_link_ops ip6erspan_tap_ops __read_mostly = {
2282 	.kind		= "ip6erspan",
2283 	.maxtype	= IFLA_GRE_MAX,
2284 	.policy		= ip6gre_policy,
2285 	.priv_size	= sizeof(struct ip6_tnl),
2286 	.setup		= ip6erspan_tap_setup,
2287 	.validate	= ip6erspan_tap_validate,
2288 	.newlink	= ip6erspan_newlink,
2289 	.changelink	= ip6erspan_changelink,
2290 	.get_size	= ip6gre_get_size,
2291 	.fill_info	= ip6gre_fill_info,
2292 	.get_link_net	= ip6_tnl_get_link_net,
2293 };
2294 
2295 /*
2296  *	And now the modules code and kernel interface.
2297  */
2298 
2299 static int __init ip6gre_init(void)
2300 {
2301 	int err;
2302 
2303 	pr_info("GRE over IPv6 tunneling driver\n");
2304 
2305 	err = register_pernet_device(&ip6gre_net_ops);
2306 	if (err < 0)
2307 		return err;
2308 
2309 	err = inet6_add_protocol(&ip6gre_protocol, IPPROTO_GRE);
2310 	if (err < 0) {
2311 		pr_info("%s: can't add protocol\n", __func__);
2312 		goto add_proto_failed;
2313 	}
2314 
2315 	err = rtnl_link_register(&ip6gre_link_ops);
2316 	if (err < 0)
2317 		goto rtnl_link_failed;
2318 
2319 	err = rtnl_link_register(&ip6gre_tap_ops);
2320 	if (err < 0)
2321 		goto tap_ops_failed;
2322 
2323 	err = rtnl_link_register(&ip6erspan_tap_ops);
2324 	if (err < 0)
2325 		goto erspan_link_failed;
2326 
2327 out:
2328 	return err;
2329 
2330 erspan_link_failed:
2331 	rtnl_link_unregister(&ip6gre_tap_ops);
2332 tap_ops_failed:
2333 	rtnl_link_unregister(&ip6gre_link_ops);
2334 rtnl_link_failed:
2335 	inet6_del_protocol(&ip6gre_protocol, IPPROTO_GRE);
2336 add_proto_failed:
2337 	unregister_pernet_device(&ip6gre_net_ops);
2338 	goto out;
2339 }
2340 
2341 static void __exit ip6gre_fini(void)
2342 {
2343 	rtnl_link_unregister(&ip6gre_tap_ops);
2344 	rtnl_link_unregister(&ip6gre_link_ops);
2345 	rtnl_link_unregister(&ip6erspan_tap_ops);
2346 	inet6_del_protocol(&ip6gre_protocol, IPPROTO_GRE);
2347 	unregister_pernet_device(&ip6gre_net_ops);
2348 }
2349 
2350 module_init(ip6gre_init);
2351 module_exit(ip6gre_fini);
2352 MODULE_LICENSE("GPL");
2353 MODULE_AUTHOR("D. Kozlov (xeb@mail.ru)");
2354 MODULE_DESCRIPTION("GRE over IPv6 tunneling device");
2355 MODULE_ALIAS_RTNL_LINK("ip6gre");
2356 MODULE_ALIAS_RTNL_LINK("ip6gretap");
2357 MODULE_ALIAS_RTNL_LINK("ip6erspan");
2358 MODULE_ALIAS_NETDEV("ip6gre0");
2359