xref: /openbmc/linux/net/ipv6/ip6_gre.c (revision ff4a7481c3898ffc3cc271d6aca431d190c37247)
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 (!ip6_tnl_xmit_ctl(t, &t->parms.laddr, &t->parms.raddr))
885 		goto tx_err;
886 
887 	switch (skb->protocol) {
888 	case htons(ETH_P_IP):
889 		ret = ip6gre_xmit_ipv4(skb, dev);
890 		break;
891 	case htons(ETH_P_IPV6):
892 		ret = ip6gre_xmit_ipv6(skb, dev);
893 		break;
894 	default:
895 		ret = ip6gre_xmit_other(skb, dev);
896 		break;
897 	}
898 
899 	if (ret < 0)
900 		goto tx_err;
901 
902 	return NETDEV_TX_OK;
903 
904 tx_err:
905 	stats->tx_errors++;
906 	stats->tx_dropped++;
907 	kfree_skb(skb);
908 	return NETDEV_TX_OK;
909 }
910 
911 static netdev_tx_t ip6erspan_tunnel_xmit(struct sk_buff *skb,
912 					 struct net_device *dev)
913 {
914 	struct ip6_tnl *t = netdev_priv(dev);
915 	struct dst_entry *dst = skb_dst(skb);
916 	struct net_device_stats *stats;
917 	bool truncate = false;
918 	int encap_limit = -1;
919 	__u8 dsfield = false;
920 	struct flowi6 fl6;
921 	int err = -EINVAL;
922 	__u32 mtu;
923 	int nhoff;
924 	int thoff;
925 
926 	if (!ip6_tnl_xmit_ctl(t, &t->parms.laddr, &t->parms.raddr))
927 		goto tx_err;
928 
929 	if (gre_handle_offloads(skb, false))
930 		goto tx_err;
931 
932 	if (skb->len > dev->mtu + dev->hard_header_len) {
933 		pskb_trim(skb, dev->mtu + dev->hard_header_len);
934 		truncate = true;
935 	}
936 
937 	nhoff = skb_network_header(skb) - skb_mac_header(skb);
938 	if (skb->protocol == htons(ETH_P_IP) &&
939 	    (ntohs(ip_hdr(skb)->tot_len) > skb->len - nhoff))
940 		truncate = true;
941 
942 	thoff = skb_transport_header(skb) - skb_mac_header(skb);
943 	if (skb->protocol == htons(ETH_P_IPV6) &&
944 	    (ntohs(ipv6_hdr(skb)->payload_len) > skb->len - thoff))
945 		truncate = true;
946 
947 	if (skb_cow_head(skb, dev->needed_headroom ?: t->hlen))
948 		goto tx_err;
949 
950 	t->parms.o_flags &= ~TUNNEL_KEY;
951 	IPCB(skb)->flags = 0;
952 
953 	/* For collect_md mode, derive fl6 from the tunnel key,
954 	 * for native mode, call prepare_ip6gre_xmit_{ipv4,ipv6}.
955 	 */
956 	if (t->parms.collect_md) {
957 		struct ip_tunnel_info *tun_info;
958 		const struct ip_tunnel_key *key;
959 		struct erspan_metadata *md;
960 		__be32 tun_id;
961 
962 		tun_info = skb_tunnel_info(skb);
963 		if (unlikely(!tun_info ||
964 			     !(tun_info->mode & IP_TUNNEL_INFO_TX) ||
965 			     ip_tunnel_info_af(tun_info) != AF_INET6))
966 			return -EINVAL;
967 
968 		key = &tun_info->key;
969 		memset(&fl6, 0, sizeof(fl6));
970 		fl6.flowi6_proto = IPPROTO_GRE;
971 		fl6.daddr = key->u.ipv6.dst;
972 		fl6.flowlabel = key->label;
973 		fl6.flowi6_uid = sock_net_uid(dev_net(dev), NULL);
974 
975 		dsfield = key->tos;
976 		if (!(tun_info->key.tun_flags & TUNNEL_ERSPAN_OPT))
977 			goto tx_err;
978 		md = ip_tunnel_info_opts(tun_info);
979 		if (!md)
980 			goto tx_err;
981 
982 		tun_id = tunnel_id_to_key32(key->tun_id);
983 		if (md->version == 1) {
984 			erspan_build_header(skb,
985 					    ntohl(tun_id),
986 					    ntohl(md->u.index), truncate,
987 					    false);
988 		} else if (md->version == 2) {
989 			erspan_build_header_v2(skb,
990 					       ntohl(tun_id),
991 					       md->u.md2.dir,
992 					       get_hwid(&md->u.md2),
993 					       truncate, false);
994 		} else {
995 			goto tx_err;
996 		}
997 	} else {
998 		struct ipv6hdr *ipv6h = ipv6_hdr(skb);
999 
1000 		switch (skb->protocol) {
1001 		case htons(ETH_P_IP):
1002 			memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
1003 			prepare_ip6gre_xmit_ipv4(skb, dev, &fl6,
1004 						 &dsfield, &encap_limit);
1005 			break;
1006 		case htons(ETH_P_IPV6):
1007 			if (ipv6_addr_equal(&t->parms.raddr, &ipv6h->saddr))
1008 				goto tx_err;
1009 			if (prepare_ip6gre_xmit_ipv6(skb, dev, &fl6,
1010 						     &dsfield, &encap_limit))
1011 				goto tx_err;
1012 			break;
1013 		default:
1014 			memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6));
1015 			break;
1016 		}
1017 
1018 		if (t->parms.erspan_ver == 1)
1019 			erspan_build_header(skb, ntohl(t->parms.o_key),
1020 					    t->parms.index,
1021 					    truncate, false);
1022 		else if (t->parms.erspan_ver == 2)
1023 			erspan_build_header_v2(skb, ntohl(t->parms.o_key),
1024 					       t->parms.dir,
1025 					       t->parms.hwid,
1026 					       truncate, false);
1027 		else
1028 			goto tx_err;
1029 
1030 		fl6.daddr = t->parms.raddr;
1031 	}
1032 
1033 	/* Push GRE header. */
1034 	gre_build_header(skb, 8, TUNNEL_SEQ,
1035 			 htons(ETH_P_ERSPAN), 0, htonl(t->o_seqno++));
1036 
1037 	/* TooBig packet may have updated dst->dev's mtu */
1038 	if (!t->parms.collect_md && dst && dst_mtu(dst) > dst->dev->mtu)
1039 		dst->ops->update_pmtu(dst, NULL, skb, dst->dev->mtu);
1040 
1041 	err = ip6_tnl_xmit(skb, dev, dsfield, &fl6, encap_limit, &mtu,
1042 			   NEXTHDR_GRE);
1043 	if (err != 0) {
1044 		/* XXX: send ICMP error even if DF is not set. */
1045 		if (err == -EMSGSIZE) {
1046 			if (skb->protocol == htons(ETH_P_IP))
1047 				icmp_send(skb, ICMP_DEST_UNREACH,
1048 					  ICMP_FRAG_NEEDED, htonl(mtu));
1049 			else
1050 				icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
1051 		}
1052 
1053 		goto tx_err;
1054 	}
1055 	return NETDEV_TX_OK;
1056 
1057 tx_err:
1058 	stats = &t->dev->stats;
1059 	stats->tx_errors++;
1060 	stats->tx_dropped++;
1061 	kfree_skb(skb);
1062 	return NETDEV_TX_OK;
1063 }
1064 
1065 static void ip6gre_tnl_link_config_common(struct ip6_tnl *t)
1066 {
1067 	struct net_device *dev = t->dev;
1068 	struct __ip6_tnl_parm *p = &t->parms;
1069 	struct flowi6 *fl6 = &t->fl.u.ip6;
1070 
1071 	if (dev->type != ARPHRD_ETHER) {
1072 		memcpy(dev->dev_addr, &p->laddr, sizeof(struct in6_addr));
1073 		memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr));
1074 	}
1075 
1076 	/* Set up flowi template */
1077 	fl6->saddr = p->laddr;
1078 	fl6->daddr = p->raddr;
1079 	fl6->flowi6_oif = p->link;
1080 	fl6->flowlabel = 0;
1081 	fl6->flowi6_proto = IPPROTO_GRE;
1082 
1083 	if (!(p->flags&IP6_TNL_F_USE_ORIG_TCLASS))
1084 		fl6->flowlabel |= IPV6_TCLASS_MASK & p->flowinfo;
1085 	if (!(p->flags&IP6_TNL_F_USE_ORIG_FLOWLABEL))
1086 		fl6->flowlabel |= IPV6_FLOWLABEL_MASK & p->flowinfo;
1087 
1088 	p->flags &= ~(IP6_TNL_F_CAP_XMIT|IP6_TNL_F_CAP_RCV|IP6_TNL_F_CAP_PER_PACKET);
1089 	p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr);
1090 
1091 	if (p->flags&IP6_TNL_F_CAP_XMIT &&
1092 			p->flags&IP6_TNL_F_CAP_RCV && dev->type != ARPHRD_ETHER)
1093 		dev->flags |= IFF_POINTOPOINT;
1094 	else
1095 		dev->flags &= ~IFF_POINTOPOINT;
1096 }
1097 
1098 static void ip6gre_tnl_link_config_route(struct ip6_tnl *t, int set_mtu,
1099 					 int t_hlen)
1100 {
1101 	const struct __ip6_tnl_parm *p = &t->parms;
1102 	struct net_device *dev = t->dev;
1103 
1104 	if (p->flags & IP6_TNL_F_CAP_XMIT) {
1105 		int strict = (ipv6_addr_type(&p->raddr) &
1106 			      (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL));
1107 
1108 		struct rt6_info *rt = rt6_lookup(t->net,
1109 						 &p->raddr, &p->laddr,
1110 						 p->link, NULL, strict);
1111 
1112 		if (!rt)
1113 			return;
1114 
1115 		if (rt->dst.dev) {
1116 			dev->needed_headroom = rt->dst.dev->hard_header_len +
1117 					       t_hlen;
1118 
1119 			if (set_mtu) {
1120 				dev->mtu = rt->dst.dev->mtu - t_hlen;
1121 				if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1122 					dev->mtu -= 8;
1123 				if (dev->type == ARPHRD_ETHER)
1124 					dev->mtu -= ETH_HLEN;
1125 
1126 				if (dev->mtu < IPV6_MIN_MTU)
1127 					dev->mtu = IPV6_MIN_MTU;
1128 			}
1129 		}
1130 		ip6_rt_put(rt);
1131 	}
1132 }
1133 
1134 static int ip6gre_calc_hlen(struct ip6_tnl *tunnel)
1135 {
1136 	int t_hlen;
1137 
1138 	tunnel->tun_hlen = gre_calc_hlen(tunnel->parms.o_flags);
1139 	tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen;
1140 
1141 	t_hlen = tunnel->hlen + sizeof(struct ipv6hdr);
1142 	tunnel->dev->needed_headroom = LL_MAX_HEADER + t_hlen;
1143 	return t_hlen;
1144 }
1145 
1146 static void ip6gre_tnl_link_config(struct ip6_tnl *t, int set_mtu)
1147 {
1148 	ip6gre_tnl_link_config_common(t);
1149 	ip6gre_tnl_link_config_route(t, set_mtu, ip6gre_calc_hlen(t));
1150 }
1151 
1152 static void ip6gre_tnl_copy_tnl_parm(struct ip6_tnl *t,
1153 				     const struct __ip6_tnl_parm *p)
1154 {
1155 	t->parms.laddr = p->laddr;
1156 	t->parms.raddr = p->raddr;
1157 	t->parms.flags = p->flags;
1158 	t->parms.hop_limit = p->hop_limit;
1159 	t->parms.encap_limit = p->encap_limit;
1160 	t->parms.flowinfo = p->flowinfo;
1161 	t->parms.link = p->link;
1162 	t->parms.proto = p->proto;
1163 	t->parms.i_key = p->i_key;
1164 	t->parms.o_key = p->o_key;
1165 	t->parms.i_flags = p->i_flags;
1166 	t->parms.o_flags = p->o_flags;
1167 	t->parms.fwmark = p->fwmark;
1168 	dst_cache_reset(&t->dst_cache);
1169 }
1170 
1171 static int ip6gre_tnl_change(struct ip6_tnl *t, const struct __ip6_tnl_parm *p,
1172 			     int set_mtu)
1173 {
1174 	ip6gre_tnl_copy_tnl_parm(t, p);
1175 	ip6gre_tnl_link_config(t, set_mtu);
1176 	return 0;
1177 }
1178 
1179 static void ip6gre_tnl_parm_from_user(struct __ip6_tnl_parm *p,
1180 	const struct ip6_tnl_parm2 *u)
1181 {
1182 	p->laddr = u->laddr;
1183 	p->raddr = u->raddr;
1184 	p->flags = u->flags;
1185 	p->hop_limit = u->hop_limit;
1186 	p->encap_limit = u->encap_limit;
1187 	p->flowinfo = u->flowinfo;
1188 	p->link = u->link;
1189 	p->i_key = u->i_key;
1190 	p->o_key = u->o_key;
1191 	p->i_flags = gre_flags_to_tnl_flags(u->i_flags);
1192 	p->o_flags = gre_flags_to_tnl_flags(u->o_flags);
1193 	memcpy(p->name, u->name, sizeof(u->name));
1194 }
1195 
1196 static void ip6gre_tnl_parm_to_user(struct ip6_tnl_parm2 *u,
1197 	const struct __ip6_tnl_parm *p)
1198 {
1199 	u->proto = IPPROTO_GRE;
1200 	u->laddr = p->laddr;
1201 	u->raddr = p->raddr;
1202 	u->flags = p->flags;
1203 	u->hop_limit = p->hop_limit;
1204 	u->encap_limit = p->encap_limit;
1205 	u->flowinfo = p->flowinfo;
1206 	u->link = p->link;
1207 	u->i_key = p->i_key;
1208 	u->o_key = p->o_key;
1209 	u->i_flags = gre_tnl_flags_to_gre_flags(p->i_flags);
1210 	u->o_flags = gre_tnl_flags_to_gre_flags(p->o_flags);
1211 	memcpy(u->name, p->name, sizeof(u->name));
1212 }
1213 
1214 static int ip6gre_tunnel_ioctl(struct net_device *dev,
1215 	struct ifreq *ifr, int cmd)
1216 {
1217 	int err = 0;
1218 	struct ip6_tnl_parm2 p;
1219 	struct __ip6_tnl_parm p1;
1220 	struct ip6_tnl *t = netdev_priv(dev);
1221 	struct net *net = t->net;
1222 	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
1223 
1224 	memset(&p1, 0, sizeof(p1));
1225 
1226 	switch (cmd) {
1227 	case SIOCGETTUNNEL:
1228 		if (dev == ign->fb_tunnel_dev) {
1229 			if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) {
1230 				err = -EFAULT;
1231 				break;
1232 			}
1233 			ip6gre_tnl_parm_from_user(&p1, &p);
1234 			t = ip6gre_tunnel_locate(net, &p1, 0);
1235 			if (!t)
1236 				t = netdev_priv(dev);
1237 		}
1238 		memset(&p, 0, sizeof(p));
1239 		ip6gre_tnl_parm_to_user(&p, &t->parms);
1240 		if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
1241 			err = -EFAULT;
1242 		break;
1243 
1244 	case SIOCADDTUNNEL:
1245 	case SIOCCHGTUNNEL:
1246 		err = -EPERM;
1247 		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1248 			goto done;
1249 
1250 		err = -EFAULT;
1251 		if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
1252 			goto done;
1253 
1254 		err = -EINVAL;
1255 		if ((p.i_flags|p.o_flags)&(GRE_VERSION|GRE_ROUTING))
1256 			goto done;
1257 
1258 		if (!(p.i_flags&GRE_KEY))
1259 			p.i_key = 0;
1260 		if (!(p.o_flags&GRE_KEY))
1261 			p.o_key = 0;
1262 
1263 		ip6gre_tnl_parm_from_user(&p1, &p);
1264 		t = ip6gre_tunnel_locate(net, &p1, cmd == SIOCADDTUNNEL);
1265 
1266 		if (dev != ign->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) {
1267 			if (t) {
1268 				if (t->dev != dev) {
1269 					err = -EEXIST;
1270 					break;
1271 				}
1272 			} else {
1273 				t = netdev_priv(dev);
1274 
1275 				ip6gre_tunnel_unlink(ign, t);
1276 				synchronize_net();
1277 				ip6gre_tnl_change(t, &p1, 1);
1278 				ip6gre_tunnel_link(ign, t);
1279 				netdev_state_change(dev);
1280 			}
1281 		}
1282 
1283 		if (t) {
1284 			err = 0;
1285 
1286 			memset(&p, 0, sizeof(p));
1287 			ip6gre_tnl_parm_to_user(&p, &t->parms);
1288 			if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
1289 				err = -EFAULT;
1290 		} else
1291 			err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
1292 		break;
1293 
1294 	case SIOCDELTUNNEL:
1295 		err = -EPERM;
1296 		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1297 			goto done;
1298 
1299 		if (dev == ign->fb_tunnel_dev) {
1300 			err = -EFAULT;
1301 			if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
1302 				goto done;
1303 			err = -ENOENT;
1304 			ip6gre_tnl_parm_from_user(&p1, &p);
1305 			t = ip6gre_tunnel_locate(net, &p1, 0);
1306 			if (!t)
1307 				goto done;
1308 			err = -EPERM;
1309 			if (t == netdev_priv(ign->fb_tunnel_dev))
1310 				goto done;
1311 			dev = t->dev;
1312 		}
1313 		unregister_netdevice(dev);
1314 		err = 0;
1315 		break;
1316 
1317 	default:
1318 		err = -EINVAL;
1319 	}
1320 
1321 done:
1322 	return err;
1323 }
1324 
1325 static int ip6gre_header(struct sk_buff *skb, struct net_device *dev,
1326 			 unsigned short type, const void *daddr,
1327 			 const void *saddr, unsigned int len)
1328 {
1329 	struct ip6_tnl *t = netdev_priv(dev);
1330 	struct ipv6hdr *ipv6h;
1331 	__be16 *p;
1332 
1333 	ipv6h = skb_push(skb, t->hlen + sizeof(*ipv6h));
1334 	ip6_flow_hdr(ipv6h, 0, ip6_make_flowlabel(dev_net(dev), skb,
1335 						  t->fl.u.ip6.flowlabel,
1336 						  true, &t->fl.u.ip6));
1337 	ipv6h->hop_limit = t->parms.hop_limit;
1338 	ipv6h->nexthdr = NEXTHDR_GRE;
1339 	ipv6h->saddr = t->parms.laddr;
1340 	ipv6h->daddr = t->parms.raddr;
1341 
1342 	p = (__be16 *)(ipv6h + 1);
1343 	p[0] = t->parms.o_flags;
1344 	p[1] = htons(type);
1345 
1346 	/*
1347 	 *	Set the source hardware address.
1348 	 */
1349 
1350 	if (saddr)
1351 		memcpy(&ipv6h->saddr, saddr, sizeof(struct in6_addr));
1352 	if (daddr)
1353 		memcpy(&ipv6h->daddr, daddr, sizeof(struct in6_addr));
1354 	if (!ipv6_addr_any(&ipv6h->daddr))
1355 		return t->hlen;
1356 
1357 	return -t->hlen;
1358 }
1359 
1360 static const struct header_ops ip6gre_header_ops = {
1361 	.create	= ip6gre_header,
1362 };
1363 
1364 static const struct net_device_ops ip6gre_netdev_ops = {
1365 	.ndo_init		= ip6gre_tunnel_init,
1366 	.ndo_uninit		= ip6gre_tunnel_uninit,
1367 	.ndo_start_xmit		= ip6gre_tunnel_xmit,
1368 	.ndo_do_ioctl		= ip6gre_tunnel_ioctl,
1369 	.ndo_change_mtu		= ip6_tnl_change_mtu,
1370 	.ndo_get_stats64	= ip_tunnel_get_stats64,
1371 	.ndo_get_iflink		= ip6_tnl_get_iflink,
1372 };
1373 
1374 static void ip6gre_dev_free(struct net_device *dev)
1375 {
1376 	struct ip6_tnl *t = netdev_priv(dev);
1377 
1378 	gro_cells_destroy(&t->gro_cells);
1379 	dst_cache_destroy(&t->dst_cache);
1380 	free_percpu(dev->tstats);
1381 }
1382 
1383 static void ip6gre_tunnel_setup(struct net_device *dev)
1384 {
1385 	dev->netdev_ops = &ip6gre_netdev_ops;
1386 	dev->needs_free_netdev = true;
1387 	dev->priv_destructor = ip6gre_dev_free;
1388 
1389 	dev->type = ARPHRD_IP6GRE;
1390 
1391 	dev->flags |= IFF_NOARP;
1392 	dev->addr_len = sizeof(struct in6_addr);
1393 	netif_keep_dst(dev);
1394 	/* This perm addr will be used as interface identifier by IPv6 */
1395 	dev->addr_assign_type = NET_ADDR_RANDOM;
1396 	eth_random_addr(dev->perm_addr);
1397 }
1398 
1399 #define GRE6_FEATURES (NETIF_F_SG |		\
1400 		       NETIF_F_FRAGLIST |	\
1401 		       NETIF_F_HIGHDMA |	\
1402 		       NETIF_F_HW_CSUM)
1403 
1404 static void ip6gre_tnl_init_features(struct net_device *dev)
1405 {
1406 	struct ip6_tnl *nt = netdev_priv(dev);
1407 
1408 	dev->features		|= GRE6_FEATURES;
1409 	dev->hw_features	|= GRE6_FEATURES;
1410 
1411 	if (!(nt->parms.o_flags & TUNNEL_SEQ)) {
1412 		/* TCP offload with GRE SEQ is not supported, nor
1413 		 * can we support 2 levels of outer headers requiring
1414 		 * an update.
1415 		 */
1416 		if (!(nt->parms.o_flags & TUNNEL_CSUM) ||
1417 		    nt->encap.type == TUNNEL_ENCAP_NONE) {
1418 			dev->features    |= NETIF_F_GSO_SOFTWARE;
1419 			dev->hw_features |= NETIF_F_GSO_SOFTWARE;
1420 		}
1421 
1422 		/* Can use a lockless transmit, unless we generate
1423 		 * output sequences
1424 		 */
1425 		dev->features |= NETIF_F_LLTX;
1426 	}
1427 }
1428 
1429 static int ip6gre_tunnel_init_common(struct net_device *dev)
1430 {
1431 	struct ip6_tnl *tunnel;
1432 	int ret;
1433 	int t_hlen;
1434 
1435 	tunnel = netdev_priv(dev);
1436 
1437 	tunnel->dev = dev;
1438 	tunnel->net = dev_net(dev);
1439 	strcpy(tunnel->parms.name, dev->name);
1440 
1441 	dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
1442 	if (!dev->tstats)
1443 		return -ENOMEM;
1444 
1445 	ret = dst_cache_init(&tunnel->dst_cache, GFP_KERNEL);
1446 	if (ret)
1447 		goto cleanup_alloc_pcpu_stats;
1448 
1449 	ret = gro_cells_init(&tunnel->gro_cells, dev);
1450 	if (ret)
1451 		goto cleanup_dst_cache_init;
1452 
1453 	t_hlen = ip6gre_calc_hlen(tunnel);
1454 	dev->mtu = ETH_DATA_LEN - t_hlen;
1455 	if (dev->type == ARPHRD_ETHER)
1456 		dev->mtu -= ETH_HLEN;
1457 	if (!(tunnel->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1458 		dev->mtu -= 8;
1459 
1460 	if (tunnel->parms.collect_md) {
1461 		dev->features |= NETIF_F_NETNS_LOCAL;
1462 		netif_keep_dst(dev);
1463 	}
1464 	ip6gre_tnl_init_features(dev);
1465 
1466 	return 0;
1467 
1468 cleanup_dst_cache_init:
1469 	dst_cache_destroy(&tunnel->dst_cache);
1470 cleanup_alloc_pcpu_stats:
1471 	free_percpu(dev->tstats);
1472 	dev->tstats = NULL;
1473 	return ret;
1474 }
1475 
1476 static int ip6gre_tunnel_init(struct net_device *dev)
1477 {
1478 	struct ip6_tnl *tunnel;
1479 	int ret;
1480 
1481 	ret = ip6gre_tunnel_init_common(dev);
1482 	if (ret)
1483 		return ret;
1484 
1485 	tunnel = netdev_priv(dev);
1486 
1487 	if (tunnel->parms.collect_md)
1488 		return 0;
1489 
1490 	memcpy(dev->dev_addr, &tunnel->parms.laddr, sizeof(struct in6_addr));
1491 	memcpy(dev->broadcast, &tunnel->parms.raddr, sizeof(struct in6_addr));
1492 
1493 	if (ipv6_addr_any(&tunnel->parms.raddr))
1494 		dev->header_ops = &ip6gre_header_ops;
1495 
1496 	return 0;
1497 }
1498 
1499 static void ip6gre_fb_tunnel_init(struct net_device *dev)
1500 {
1501 	struct ip6_tnl *tunnel = netdev_priv(dev);
1502 
1503 	tunnel->dev = dev;
1504 	tunnel->net = dev_net(dev);
1505 	strcpy(tunnel->parms.name, dev->name);
1506 
1507 	tunnel->hlen		= sizeof(struct ipv6hdr) + 4;
1508 
1509 	dev_hold(dev);
1510 }
1511 
1512 static struct inet6_protocol ip6gre_protocol __read_mostly = {
1513 	.handler     = gre_rcv,
1514 	.err_handler = ip6gre_err,
1515 	.flags       = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
1516 };
1517 
1518 static void ip6gre_destroy_tunnels(struct net *net, struct list_head *head)
1519 {
1520 	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
1521 	struct net_device *dev, *aux;
1522 	int prio;
1523 
1524 	for_each_netdev_safe(net, dev, aux)
1525 		if (dev->rtnl_link_ops == &ip6gre_link_ops ||
1526 		    dev->rtnl_link_ops == &ip6gre_tap_ops ||
1527 		    dev->rtnl_link_ops == &ip6erspan_tap_ops)
1528 			unregister_netdevice_queue(dev, head);
1529 
1530 	for (prio = 0; prio < 4; prio++) {
1531 		int h;
1532 		for (h = 0; h < IP6_GRE_HASH_SIZE; h++) {
1533 			struct ip6_tnl *t;
1534 
1535 			t = rtnl_dereference(ign->tunnels[prio][h]);
1536 
1537 			while (t) {
1538 				/* If dev is in the same netns, it has already
1539 				 * been added to the list by the previous loop.
1540 				 */
1541 				if (!net_eq(dev_net(t->dev), net))
1542 					unregister_netdevice_queue(t->dev,
1543 								   head);
1544 				t = rtnl_dereference(t->next);
1545 			}
1546 		}
1547 	}
1548 }
1549 
1550 static int __net_init ip6gre_init_net(struct net *net)
1551 {
1552 	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
1553 	int err;
1554 
1555 	if (!net_has_fallback_tunnels(net))
1556 		return 0;
1557 	ign->fb_tunnel_dev = alloc_netdev(sizeof(struct ip6_tnl), "ip6gre0",
1558 					  NET_NAME_UNKNOWN,
1559 					  ip6gre_tunnel_setup);
1560 	if (!ign->fb_tunnel_dev) {
1561 		err = -ENOMEM;
1562 		goto err_alloc_dev;
1563 	}
1564 	dev_net_set(ign->fb_tunnel_dev, net);
1565 	/* FB netdevice is special: we have one, and only one per netns.
1566 	 * Allowing to move it to another netns is clearly unsafe.
1567 	 */
1568 	ign->fb_tunnel_dev->features |= NETIF_F_NETNS_LOCAL;
1569 
1570 
1571 	ip6gre_fb_tunnel_init(ign->fb_tunnel_dev);
1572 	ign->fb_tunnel_dev->rtnl_link_ops = &ip6gre_link_ops;
1573 
1574 	err = register_netdev(ign->fb_tunnel_dev);
1575 	if (err)
1576 		goto err_reg_dev;
1577 
1578 	rcu_assign_pointer(ign->tunnels_wc[0],
1579 			   netdev_priv(ign->fb_tunnel_dev));
1580 	return 0;
1581 
1582 err_reg_dev:
1583 	free_netdev(ign->fb_tunnel_dev);
1584 err_alloc_dev:
1585 	return err;
1586 }
1587 
1588 static void __net_exit ip6gre_exit_batch_net(struct list_head *net_list)
1589 {
1590 	struct net *net;
1591 	LIST_HEAD(list);
1592 
1593 	rtnl_lock();
1594 	list_for_each_entry(net, net_list, exit_list)
1595 		ip6gre_destroy_tunnels(net, &list);
1596 	unregister_netdevice_many(&list);
1597 	rtnl_unlock();
1598 }
1599 
1600 static struct pernet_operations ip6gre_net_ops = {
1601 	.init = ip6gre_init_net,
1602 	.exit_batch = ip6gre_exit_batch_net,
1603 	.id   = &ip6gre_net_id,
1604 	.size = sizeof(struct ip6gre_net),
1605 };
1606 
1607 static int ip6gre_tunnel_validate(struct nlattr *tb[], struct nlattr *data[],
1608 				  struct netlink_ext_ack *extack)
1609 {
1610 	__be16 flags;
1611 
1612 	if (!data)
1613 		return 0;
1614 
1615 	flags = 0;
1616 	if (data[IFLA_GRE_IFLAGS])
1617 		flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]);
1618 	if (data[IFLA_GRE_OFLAGS])
1619 		flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]);
1620 	if (flags & (GRE_VERSION|GRE_ROUTING))
1621 		return -EINVAL;
1622 
1623 	return 0;
1624 }
1625 
1626 static int ip6gre_tap_validate(struct nlattr *tb[], struct nlattr *data[],
1627 			       struct netlink_ext_ack *extack)
1628 {
1629 	struct in6_addr daddr;
1630 
1631 	if (tb[IFLA_ADDRESS]) {
1632 		if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
1633 			return -EINVAL;
1634 		if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
1635 			return -EADDRNOTAVAIL;
1636 	}
1637 
1638 	if (!data)
1639 		goto out;
1640 
1641 	if (data[IFLA_GRE_REMOTE]) {
1642 		daddr = nla_get_in6_addr(data[IFLA_GRE_REMOTE]);
1643 		if (ipv6_addr_any(&daddr))
1644 			return -EINVAL;
1645 	}
1646 
1647 out:
1648 	return ip6gre_tunnel_validate(tb, data, extack);
1649 }
1650 
1651 static int ip6erspan_tap_validate(struct nlattr *tb[], struct nlattr *data[],
1652 				  struct netlink_ext_ack *extack)
1653 {
1654 	__be16 flags = 0;
1655 	int ret, ver = 0;
1656 
1657 	if (!data)
1658 		return 0;
1659 
1660 	ret = ip6gre_tap_validate(tb, data, extack);
1661 	if (ret)
1662 		return ret;
1663 
1664 	/* ERSPAN should only have GRE sequence and key flag */
1665 	if (data[IFLA_GRE_OFLAGS])
1666 		flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]);
1667 	if (data[IFLA_GRE_IFLAGS])
1668 		flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]);
1669 	if (!data[IFLA_GRE_COLLECT_METADATA] &&
1670 	    flags != (GRE_SEQ | GRE_KEY))
1671 		return -EINVAL;
1672 
1673 	/* ERSPAN Session ID only has 10-bit. Since we reuse
1674 	 * 32-bit key field as ID, check it's range.
1675 	 */
1676 	if (data[IFLA_GRE_IKEY] &&
1677 	    (ntohl(nla_get_be32(data[IFLA_GRE_IKEY])) & ~ID_MASK))
1678 		return -EINVAL;
1679 
1680 	if (data[IFLA_GRE_OKEY] &&
1681 	    (ntohl(nla_get_be32(data[IFLA_GRE_OKEY])) & ~ID_MASK))
1682 		return -EINVAL;
1683 
1684 	if (data[IFLA_GRE_ERSPAN_VER]) {
1685 		ver = nla_get_u8(data[IFLA_GRE_ERSPAN_VER]);
1686 		if (ver != 1 && ver != 2)
1687 			return -EINVAL;
1688 	}
1689 
1690 	if (ver == 1) {
1691 		if (data[IFLA_GRE_ERSPAN_INDEX]) {
1692 			u32 index = nla_get_u32(data[IFLA_GRE_ERSPAN_INDEX]);
1693 
1694 			if (index & ~INDEX_MASK)
1695 				return -EINVAL;
1696 		}
1697 	} else if (ver == 2) {
1698 		if (data[IFLA_GRE_ERSPAN_DIR]) {
1699 			u16 dir = nla_get_u8(data[IFLA_GRE_ERSPAN_DIR]);
1700 
1701 			if (dir & ~(DIR_MASK >> DIR_OFFSET))
1702 				return -EINVAL;
1703 		}
1704 
1705 		if (data[IFLA_GRE_ERSPAN_HWID]) {
1706 			u16 hwid = nla_get_u16(data[IFLA_GRE_ERSPAN_HWID]);
1707 
1708 			if (hwid & ~(HWID_MASK >> HWID_OFFSET))
1709 				return -EINVAL;
1710 		}
1711 	}
1712 
1713 	return 0;
1714 }
1715 
1716 static void ip6gre_netlink_parms(struct nlattr *data[],
1717 				struct __ip6_tnl_parm *parms)
1718 {
1719 	memset(parms, 0, sizeof(*parms));
1720 
1721 	if (!data)
1722 		return;
1723 
1724 	if (data[IFLA_GRE_LINK])
1725 		parms->link = nla_get_u32(data[IFLA_GRE_LINK]);
1726 
1727 	if (data[IFLA_GRE_IFLAGS])
1728 		parms->i_flags = gre_flags_to_tnl_flags(
1729 				nla_get_be16(data[IFLA_GRE_IFLAGS]));
1730 
1731 	if (data[IFLA_GRE_OFLAGS])
1732 		parms->o_flags = gre_flags_to_tnl_flags(
1733 				nla_get_be16(data[IFLA_GRE_OFLAGS]));
1734 
1735 	if (data[IFLA_GRE_IKEY])
1736 		parms->i_key = nla_get_be32(data[IFLA_GRE_IKEY]);
1737 
1738 	if (data[IFLA_GRE_OKEY])
1739 		parms->o_key = nla_get_be32(data[IFLA_GRE_OKEY]);
1740 
1741 	if (data[IFLA_GRE_LOCAL])
1742 		parms->laddr = nla_get_in6_addr(data[IFLA_GRE_LOCAL]);
1743 
1744 	if (data[IFLA_GRE_REMOTE])
1745 		parms->raddr = nla_get_in6_addr(data[IFLA_GRE_REMOTE]);
1746 
1747 	if (data[IFLA_GRE_TTL])
1748 		parms->hop_limit = nla_get_u8(data[IFLA_GRE_TTL]);
1749 
1750 	if (data[IFLA_GRE_ENCAP_LIMIT])
1751 		parms->encap_limit = nla_get_u8(data[IFLA_GRE_ENCAP_LIMIT]);
1752 
1753 	if (data[IFLA_GRE_FLOWINFO])
1754 		parms->flowinfo = nla_get_be32(data[IFLA_GRE_FLOWINFO]);
1755 
1756 	if (data[IFLA_GRE_FLAGS])
1757 		parms->flags = nla_get_u32(data[IFLA_GRE_FLAGS]);
1758 
1759 	if (data[IFLA_GRE_FWMARK])
1760 		parms->fwmark = nla_get_u32(data[IFLA_GRE_FWMARK]);
1761 
1762 	if (data[IFLA_GRE_COLLECT_METADATA])
1763 		parms->collect_md = true;
1764 
1765 	parms->erspan_ver = 1;
1766 	if (data[IFLA_GRE_ERSPAN_VER])
1767 		parms->erspan_ver = nla_get_u8(data[IFLA_GRE_ERSPAN_VER]);
1768 
1769 	if (parms->erspan_ver == 1) {
1770 		if (data[IFLA_GRE_ERSPAN_INDEX])
1771 			parms->index = nla_get_u32(data[IFLA_GRE_ERSPAN_INDEX]);
1772 	} else if (parms->erspan_ver == 2) {
1773 		if (data[IFLA_GRE_ERSPAN_DIR])
1774 			parms->dir = nla_get_u8(data[IFLA_GRE_ERSPAN_DIR]);
1775 		if (data[IFLA_GRE_ERSPAN_HWID])
1776 			parms->hwid = nla_get_u16(data[IFLA_GRE_ERSPAN_HWID]);
1777 	}
1778 }
1779 
1780 static int ip6gre_tap_init(struct net_device *dev)
1781 {
1782 	int ret;
1783 
1784 	ret = ip6gre_tunnel_init_common(dev);
1785 	if (ret)
1786 		return ret;
1787 
1788 	dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1789 
1790 	return 0;
1791 }
1792 
1793 static const struct net_device_ops ip6gre_tap_netdev_ops = {
1794 	.ndo_init = ip6gre_tap_init,
1795 	.ndo_uninit = ip6gre_tunnel_uninit,
1796 	.ndo_start_xmit = ip6gre_tunnel_xmit,
1797 	.ndo_set_mac_address = eth_mac_addr,
1798 	.ndo_validate_addr = eth_validate_addr,
1799 	.ndo_change_mtu = ip6_tnl_change_mtu,
1800 	.ndo_get_stats64 = ip_tunnel_get_stats64,
1801 	.ndo_get_iflink = ip6_tnl_get_iflink,
1802 };
1803 
1804 static int ip6erspan_calc_hlen(struct ip6_tnl *tunnel)
1805 {
1806 	int t_hlen;
1807 
1808 	tunnel->tun_hlen = 8;
1809 	tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen +
1810 		       erspan_hdr_len(tunnel->parms.erspan_ver);
1811 
1812 	t_hlen = tunnel->hlen + sizeof(struct ipv6hdr);
1813 	tunnel->dev->needed_headroom = LL_MAX_HEADER + t_hlen;
1814 	return t_hlen;
1815 }
1816 
1817 static int ip6erspan_tap_init(struct net_device *dev)
1818 {
1819 	struct ip6_tnl *tunnel;
1820 	int t_hlen;
1821 	int ret;
1822 
1823 	tunnel = netdev_priv(dev);
1824 
1825 	tunnel->dev = dev;
1826 	tunnel->net = dev_net(dev);
1827 	strcpy(tunnel->parms.name, dev->name);
1828 
1829 	dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
1830 	if (!dev->tstats)
1831 		return -ENOMEM;
1832 
1833 	ret = dst_cache_init(&tunnel->dst_cache, GFP_KERNEL);
1834 	if (ret)
1835 		goto cleanup_alloc_pcpu_stats;
1836 
1837 	ret = gro_cells_init(&tunnel->gro_cells, dev);
1838 	if (ret)
1839 		goto cleanup_dst_cache_init;
1840 
1841 	t_hlen = ip6erspan_calc_hlen(tunnel);
1842 	dev->mtu = ETH_DATA_LEN - t_hlen;
1843 	if (dev->type == ARPHRD_ETHER)
1844 		dev->mtu -= ETH_HLEN;
1845 	if (!(tunnel->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1846 		dev->mtu -= 8;
1847 
1848 	dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1849 	ip6erspan_tnl_link_config(tunnel, 1);
1850 
1851 	return 0;
1852 
1853 cleanup_dst_cache_init:
1854 	dst_cache_destroy(&tunnel->dst_cache);
1855 cleanup_alloc_pcpu_stats:
1856 	free_percpu(dev->tstats);
1857 	dev->tstats = NULL;
1858 	return ret;
1859 }
1860 
1861 static const struct net_device_ops ip6erspan_netdev_ops = {
1862 	.ndo_init =		ip6erspan_tap_init,
1863 	.ndo_uninit =		ip6erspan_tunnel_uninit,
1864 	.ndo_start_xmit =	ip6erspan_tunnel_xmit,
1865 	.ndo_set_mac_address =	eth_mac_addr,
1866 	.ndo_validate_addr =	eth_validate_addr,
1867 	.ndo_change_mtu =	ip6_tnl_change_mtu,
1868 	.ndo_get_stats64 =	ip_tunnel_get_stats64,
1869 	.ndo_get_iflink =	ip6_tnl_get_iflink,
1870 };
1871 
1872 static void ip6gre_tap_setup(struct net_device *dev)
1873 {
1874 
1875 	ether_setup(dev);
1876 
1877 	dev->max_mtu = 0;
1878 	dev->netdev_ops = &ip6gre_tap_netdev_ops;
1879 	dev->needs_free_netdev = true;
1880 	dev->priv_destructor = ip6gre_dev_free;
1881 
1882 	dev->features |= NETIF_F_NETNS_LOCAL;
1883 	dev->priv_flags &= ~IFF_TX_SKB_SHARING;
1884 	dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1885 	netif_keep_dst(dev);
1886 }
1887 
1888 static bool ip6gre_netlink_encap_parms(struct nlattr *data[],
1889 				       struct ip_tunnel_encap *ipencap)
1890 {
1891 	bool ret = false;
1892 
1893 	memset(ipencap, 0, sizeof(*ipencap));
1894 
1895 	if (!data)
1896 		return ret;
1897 
1898 	if (data[IFLA_GRE_ENCAP_TYPE]) {
1899 		ret = true;
1900 		ipencap->type = nla_get_u16(data[IFLA_GRE_ENCAP_TYPE]);
1901 	}
1902 
1903 	if (data[IFLA_GRE_ENCAP_FLAGS]) {
1904 		ret = true;
1905 		ipencap->flags = nla_get_u16(data[IFLA_GRE_ENCAP_FLAGS]);
1906 	}
1907 
1908 	if (data[IFLA_GRE_ENCAP_SPORT]) {
1909 		ret = true;
1910 		ipencap->sport = nla_get_be16(data[IFLA_GRE_ENCAP_SPORT]);
1911 	}
1912 
1913 	if (data[IFLA_GRE_ENCAP_DPORT]) {
1914 		ret = true;
1915 		ipencap->dport = nla_get_be16(data[IFLA_GRE_ENCAP_DPORT]);
1916 	}
1917 
1918 	return ret;
1919 }
1920 
1921 static int ip6gre_newlink_common(struct net *src_net, struct net_device *dev,
1922 				 struct nlattr *tb[], struct nlattr *data[],
1923 				 struct netlink_ext_ack *extack)
1924 {
1925 	struct ip6_tnl *nt;
1926 	struct ip_tunnel_encap ipencap;
1927 	int err;
1928 
1929 	nt = netdev_priv(dev);
1930 
1931 	if (ip6gre_netlink_encap_parms(data, &ipencap)) {
1932 		int err = ip6_tnl_encap_setup(nt, &ipencap);
1933 
1934 		if (err < 0)
1935 			return err;
1936 	}
1937 
1938 	if (dev->type == ARPHRD_ETHER && !tb[IFLA_ADDRESS])
1939 		eth_hw_addr_random(dev);
1940 
1941 	nt->dev = dev;
1942 	nt->net = dev_net(dev);
1943 
1944 	err = register_netdevice(dev);
1945 	if (err)
1946 		goto out;
1947 
1948 	if (tb[IFLA_MTU])
1949 		ip6_tnl_change_mtu(dev, nla_get_u32(tb[IFLA_MTU]));
1950 
1951 	dev_hold(dev);
1952 
1953 out:
1954 	return err;
1955 }
1956 
1957 static int ip6gre_newlink(struct net *src_net, struct net_device *dev,
1958 			  struct nlattr *tb[], struct nlattr *data[],
1959 			  struct netlink_ext_ack *extack)
1960 {
1961 	struct ip6_tnl *nt = netdev_priv(dev);
1962 	struct net *net = dev_net(dev);
1963 	struct ip6gre_net *ign;
1964 	int err;
1965 
1966 	ip6gre_netlink_parms(data, &nt->parms);
1967 	ign = net_generic(net, ip6gre_net_id);
1968 
1969 	if (nt->parms.collect_md) {
1970 		if (rtnl_dereference(ign->collect_md_tun))
1971 			return -EEXIST;
1972 	} else {
1973 		if (ip6gre_tunnel_find(net, &nt->parms, dev->type))
1974 			return -EEXIST;
1975 	}
1976 
1977 	err = ip6gre_newlink_common(src_net, dev, tb, data, extack);
1978 	if (!err) {
1979 		ip6gre_tnl_link_config(nt, !tb[IFLA_MTU]);
1980 		ip6gre_tunnel_link_md(ign, nt);
1981 		ip6gre_tunnel_link(net_generic(net, ip6gre_net_id), nt);
1982 	}
1983 	return err;
1984 }
1985 
1986 static struct ip6_tnl *
1987 ip6gre_changelink_common(struct net_device *dev, struct nlattr *tb[],
1988 			 struct nlattr *data[], struct __ip6_tnl_parm *p_p,
1989 			 struct netlink_ext_ack *extack)
1990 {
1991 	struct ip6_tnl *t, *nt = netdev_priv(dev);
1992 	struct net *net = nt->net;
1993 	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
1994 	struct ip_tunnel_encap ipencap;
1995 
1996 	if (dev == ign->fb_tunnel_dev)
1997 		return ERR_PTR(-EINVAL);
1998 
1999 	if (ip6gre_netlink_encap_parms(data, &ipencap)) {
2000 		int err = ip6_tnl_encap_setup(nt, &ipencap);
2001 
2002 		if (err < 0)
2003 			return ERR_PTR(err);
2004 	}
2005 
2006 	ip6gre_netlink_parms(data, p_p);
2007 
2008 	t = ip6gre_tunnel_locate(net, p_p, 0);
2009 
2010 	if (t) {
2011 		if (t->dev != dev)
2012 			return ERR_PTR(-EEXIST);
2013 	} else {
2014 		t = nt;
2015 	}
2016 
2017 	return t;
2018 }
2019 
2020 static int ip6gre_changelink(struct net_device *dev, struct nlattr *tb[],
2021 			     struct nlattr *data[],
2022 			     struct netlink_ext_ack *extack)
2023 {
2024 	struct ip6gre_net *ign = net_generic(dev_net(dev), ip6gre_net_id);
2025 	struct __ip6_tnl_parm p;
2026 	struct ip6_tnl *t;
2027 
2028 	t = ip6gre_changelink_common(dev, tb, data, &p, extack);
2029 	if (IS_ERR(t))
2030 		return PTR_ERR(t);
2031 
2032 	ip6gre_tunnel_unlink_md(ign, t);
2033 	ip6gre_tunnel_unlink(ign, t);
2034 	ip6gre_tnl_change(t, &p, !tb[IFLA_MTU]);
2035 	ip6gre_tunnel_link_md(ign, t);
2036 	ip6gre_tunnel_link(ign, t);
2037 	return 0;
2038 }
2039 
2040 static void ip6gre_dellink(struct net_device *dev, struct list_head *head)
2041 {
2042 	struct net *net = dev_net(dev);
2043 	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
2044 
2045 	if (dev != ign->fb_tunnel_dev)
2046 		unregister_netdevice_queue(dev, head);
2047 }
2048 
2049 static size_t ip6gre_get_size(const struct net_device *dev)
2050 {
2051 	return
2052 		/* IFLA_GRE_LINK */
2053 		nla_total_size(4) +
2054 		/* IFLA_GRE_IFLAGS */
2055 		nla_total_size(2) +
2056 		/* IFLA_GRE_OFLAGS */
2057 		nla_total_size(2) +
2058 		/* IFLA_GRE_IKEY */
2059 		nla_total_size(4) +
2060 		/* IFLA_GRE_OKEY */
2061 		nla_total_size(4) +
2062 		/* IFLA_GRE_LOCAL */
2063 		nla_total_size(sizeof(struct in6_addr)) +
2064 		/* IFLA_GRE_REMOTE */
2065 		nla_total_size(sizeof(struct in6_addr)) +
2066 		/* IFLA_GRE_TTL */
2067 		nla_total_size(1) +
2068 		/* IFLA_GRE_ENCAP_LIMIT */
2069 		nla_total_size(1) +
2070 		/* IFLA_GRE_FLOWINFO */
2071 		nla_total_size(4) +
2072 		/* IFLA_GRE_FLAGS */
2073 		nla_total_size(4) +
2074 		/* IFLA_GRE_ENCAP_TYPE */
2075 		nla_total_size(2) +
2076 		/* IFLA_GRE_ENCAP_FLAGS */
2077 		nla_total_size(2) +
2078 		/* IFLA_GRE_ENCAP_SPORT */
2079 		nla_total_size(2) +
2080 		/* IFLA_GRE_ENCAP_DPORT */
2081 		nla_total_size(2) +
2082 		/* IFLA_GRE_COLLECT_METADATA */
2083 		nla_total_size(0) +
2084 		/* IFLA_GRE_FWMARK */
2085 		nla_total_size(4) +
2086 		/* IFLA_GRE_ERSPAN_INDEX */
2087 		nla_total_size(4) +
2088 		0;
2089 }
2090 
2091 static int ip6gre_fill_info(struct sk_buff *skb, const struct net_device *dev)
2092 {
2093 	struct ip6_tnl *t = netdev_priv(dev);
2094 	struct __ip6_tnl_parm *p = &t->parms;
2095 
2096 	if (nla_put_u32(skb, IFLA_GRE_LINK, p->link) ||
2097 	    nla_put_be16(skb, IFLA_GRE_IFLAGS,
2098 			 gre_tnl_flags_to_gre_flags(p->i_flags)) ||
2099 	    nla_put_be16(skb, IFLA_GRE_OFLAGS,
2100 			 gre_tnl_flags_to_gre_flags(p->o_flags)) ||
2101 	    nla_put_be32(skb, IFLA_GRE_IKEY, p->i_key) ||
2102 	    nla_put_be32(skb, IFLA_GRE_OKEY, p->o_key) ||
2103 	    nla_put_in6_addr(skb, IFLA_GRE_LOCAL, &p->laddr) ||
2104 	    nla_put_in6_addr(skb, IFLA_GRE_REMOTE, &p->raddr) ||
2105 	    nla_put_u8(skb, IFLA_GRE_TTL, p->hop_limit) ||
2106 	    nla_put_u8(skb, IFLA_GRE_ENCAP_LIMIT, p->encap_limit) ||
2107 	    nla_put_be32(skb, IFLA_GRE_FLOWINFO, p->flowinfo) ||
2108 	    nla_put_u32(skb, IFLA_GRE_FLAGS, p->flags) ||
2109 	    nla_put_u32(skb, IFLA_GRE_FWMARK, p->fwmark) ||
2110 	    nla_put_u32(skb, IFLA_GRE_ERSPAN_INDEX, p->index))
2111 		goto nla_put_failure;
2112 
2113 	if (nla_put_u16(skb, IFLA_GRE_ENCAP_TYPE,
2114 			t->encap.type) ||
2115 	    nla_put_be16(skb, IFLA_GRE_ENCAP_SPORT,
2116 			 t->encap.sport) ||
2117 	    nla_put_be16(skb, IFLA_GRE_ENCAP_DPORT,
2118 			 t->encap.dport) ||
2119 	    nla_put_u16(skb, IFLA_GRE_ENCAP_FLAGS,
2120 			t->encap.flags))
2121 		goto nla_put_failure;
2122 
2123 	if (p->collect_md) {
2124 		if (nla_put_flag(skb, IFLA_GRE_COLLECT_METADATA))
2125 			goto nla_put_failure;
2126 	}
2127 
2128 	if (nla_put_u8(skb, IFLA_GRE_ERSPAN_VER, p->erspan_ver))
2129 		goto nla_put_failure;
2130 
2131 	if (p->erspan_ver == 1) {
2132 		if (nla_put_u32(skb, IFLA_GRE_ERSPAN_INDEX, p->index))
2133 			goto nla_put_failure;
2134 	} else if (p->erspan_ver == 2) {
2135 		if (nla_put_u8(skb, IFLA_GRE_ERSPAN_DIR, p->dir))
2136 			goto nla_put_failure;
2137 		if (nla_put_u16(skb, IFLA_GRE_ERSPAN_HWID, p->hwid))
2138 			goto nla_put_failure;
2139 	}
2140 
2141 	return 0;
2142 
2143 nla_put_failure:
2144 	return -EMSGSIZE;
2145 }
2146 
2147 static const struct nla_policy ip6gre_policy[IFLA_GRE_MAX + 1] = {
2148 	[IFLA_GRE_LINK]        = { .type = NLA_U32 },
2149 	[IFLA_GRE_IFLAGS]      = { .type = NLA_U16 },
2150 	[IFLA_GRE_OFLAGS]      = { .type = NLA_U16 },
2151 	[IFLA_GRE_IKEY]        = { .type = NLA_U32 },
2152 	[IFLA_GRE_OKEY]        = { .type = NLA_U32 },
2153 	[IFLA_GRE_LOCAL]       = { .len = FIELD_SIZEOF(struct ipv6hdr, saddr) },
2154 	[IFLA_GRE_REMOTE]      = { .len = FIELD_SIZEOF(struct ipv6hdr, daddr) },
2155 	[IFLA_GRE_TTL]         = { .type = NLA_U8 },
2156 	[IFLA_GRE_ENCAP_LIMIT] = { .type = NLA_U8 },
2157 	[IFLA_GRE_FLOWINFO]    = { .type = NLA_U32 },
2158 	[IFLA_GRE_FLAGS]       = { .type = NLA_U32 },
2159 	[IFLA_GRE_ENCAP_TYPE]   = { .type = NLA_U16 },
2160 	[IFLA_GRE_ENCAP_FLAGS]  = { .type = NLA_U16 },
2161 	[IFLA_GRE_ENCAP_SPORT]  = { .type = NLA_U16 },
2162 	[IFLA_GRE_ENCAP_DPORT]  = { .type = NLA_U16 },
2163 	[IFLA_GRE_COLLECT_METADATA] = { .type = NLA_FLAG },
2164 	[IFLA_GRE_FWMARK]       = { .type = NLA_U32 },
2165 	[IFLA_GRE_ERSPAN_INDEX] = { .type = NLA_U32 },
2166 	[IFLA_GRE_ERSPAN_VER]	= { .type = NLA_U8 },
2167 	[IFLA_GRE_ERSPAN_DIR]	= { .type = NLA_U8 },
2168 	[IFLA_GRE_ERSPAN_HWID]	= { .type = NLA_U16 },
2169 };
2170 
2171 static void ip6erspan_tap_setup(struct net_device *dev)
2172 {
2173 	ether_setup(dev);
2174 
2175 	dev->netdev_ops = &ip6erspan_netdev_ops;
2176 	dev->needs_free_netdev = true;
2177 	dev->priv_destructor = ip6gre_dev_free;
2178 
2179 	dev->features |= NETIF_F_NETNS_LOCAL;
2180 	dev->priv_flags &= ~IFF_TX_SKB_SHARING;
2181 	dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
2182 	netif_keep_dst(dev);
2183 }
2184 
2185 static int ip6erspan_newlink(struct net *src_net, struct net_device *dev,
2186 			     struct nlattr *tb[], struct nlattr *data[],
2187 			     struct netlink_ext_ack *extack)
2188 {
2189 	struct ip6_tnl *nt = netdev_priv(dev);
2190 	struct net *net = dev_net(dev);
2191 	struct ip6gre_net *ign;
2192 	int err;
2193 
2194 	ip6gre_netlink_parms(data, &nt->parms);
2195 	ign = net_generic(net, ip6gre_net_id);
2196 
2197 	if (nt->parms.collect_md) {
2198 		if (rtnl_dereference(ign->collect_md_tun_erspan))
2199 			return -EEXIST;
2200 	} else {
2201 		if (ip6gre_tunnel_find(net, &nt->parms, dev->type))
2202 			return -EEXIST;
2203 	}
2204 
2205 	err = ip6gre_newlink_common(src_net, dev, tb, data, extack);
2206 	if (!err) {
2207 		ip6erspan_tnl_link_config(nt, !tb[IFLA_MTU]);
2208 		ip6erspan_tunnel_link_md(ign, nt);
2209 		ip6gre_tunnel_link(net_generic(net, ip6gre_net_id), nt);
2210 	}
2211 	return err;
2212 }
2213 
2214 static void ip6erspan_tnl_link_config(struct ip6_tnl *t, int set_mtu)
2215 {
2216 	ip6gre_tnl_link_config_common(t);
2217 	ip6gre_tnl_link_config_route(t, set_mtu, ip6erspan_calc_hlen(t));
2218 }
2219 
2220 static int ip6erspan_tnl_change(struct ip6_tnl *t,
2221 				const struct __ip6_tnl_parm *p, int set_mtu)
2222 {
2223 	ip6gre_tnl_copy_tnl_parm(t, p);
2224 	ip6erspan_tnl_link_config(t, set_mtu);
2225 	return 0;
2226 }
2227 
2228 static int ip6erspan_changelink(struct net_device *dev, struct nlattr *tb[],
2229 				struct nlattr *data[],
2230 				struct netlink_ext_ack *extack)
2231 {
2232 	struct ip6gre_net *ign = net_generic(dev_net(dev), ip6gre_net_id);
2233 	struct __ip6_tnl_parm p;
2234 	struct ip6_tnl *t;
2235 
2236 	t = ip6gre_changelink_common(dev, tb, data, &p, extack);
2237 	if (IS_ERR(t))
2238 		return PTR_ERR(t);
2239 
2240 	ip6gre_tunnel_unlink_md(ign, t);
2241 	ip6gre_tunnel_unlink(ign, t);
2242 	ip6erspan_tnl_change(t, &p, !tb[IFLA_MTU]);
2243 	ip6erspan_tunnel_link_md(ign, t);
2244 	ip6gre_tunnel_link(ign, t);
2245 	return 0;
2246 }
2247 
2248 static struct rtnl_link_ops ip6gre_link_ops __read_mostly = {
2249 	.kind		= "ip6gre",
2250 	.maxtype	= IFLA_GRE_MAX,
2251 	.policy		= ip6gre_policy,
2252 	.priv_size	= sizeof(struct ip6_tnl),
2253 	.setup		= ip6gre_tunnel_setup,
2254 	.validate	= ip6gre_tunnel_validate,
2255 	.newlink	= ip6gre_newlink,
2256 	.changelink	= ip6gre_changelink,
2257 	.dellink	= ip6gre_dellink,
2258 	.get_size	= ip6gre_get_size,
2259 	.fill_info	= ip6gre_fill_info,
2260 	.get_link_net	= ip6_tnl_get_link_net,
2261 };
2262 
2263 static struct rtnl_link_ops ip6gre_tap_ops __read_mostly = {
2264 	.kind		= "ip6gretap",
2265 	.maxtype	= IFLA_GRE_MAX,
2266 	.policy		= ip6gre_policy,
2267 	.priv_size	= sizeof(struct ip6_tnl),
2268 	.setup		= ip6gre_tap_setup,
2269 	.validate	= ip6gre_tap_validate,
2270 	.newlink	= ip6gre_newlink,
2271 	.changelink	= ip6gre_changelink,
2272 	.get_size	= ip6gre_get_size,
2273 	.fill_info	= ip6gre_fill_info,
2274 	.get_link_net	= ip6_tnl_get_link_net,
2275 };
2276 
2277 static struct rtnl_link_ops ip6erspan_tap_ops __read_mostly = {
2278 	.kind		= "ip6erspan",
2279 	.maxtype	= IFLA_GRE_MAX,
2280 	.policy		= ip6gre_policy,
2281 	.priv_size	= sizeof(struct ip6_tnl),
2282 	.setup		= ip6erspan_tap_setup,
2283 	.validate	= ip6erspan_tap_validate,
2284 	.newlink	= ip6erspan_newlink,
2285 	.changelink	= ip6erspan_changelink,
2286 	.get_size	= ip6gre_get_size,
2287 	.fill_info	= ip6gre_fill_info,
2288 	.get_link_net	= ip6_tnl_get_link_net,
2289 };
2290 
2291 /*
2292  *	And now the modules code and kernel interface.
2293  */
2294 
2295 static int __init ip6gre_init(void)
2296 {
2297 	int err;
2298 
2299 	pr_info("GRE over IPv6 tunneling driver\n");
2300 
2301 	err = register_pernet_device(&ip6gre_net_ops);
2302 	if (err < 0)
2303 		return err;
2304 
2305 	err = inet6_add_protocol(&ip6gre_protocol, IPPROTO_GRE);
2306 	if (err < 0) {
2307 		pr_info("%s: can't add protocol\n", __func__);
2308 		goto add_proto_failed;
2309 	}
2310 
2311 	err = rtnl_link_register(&ip6gre_link_ops);
2312 	if (err < 0)
2313 		goto rtnl_link_failed;
2314 
2315 	err = rtnl_link_register(&ip6gre_tap_ops);
2316 	if (err < 0)
2317 		goto tap_ops_failed;
2318 
2319 	err = rtnl_link_register(&ip6erspan_tap_ops);
2320 	if (err < 0)
2321 		goto erspan_link_failed;
2322 
2323 out:
2324 	return err;
2325 
2326 erspan_link_failed:
2327 	rtnl_link_unregister(&ip6gre_tap_ops);
2328 tap_ops_failed:
2329 	rtnl_link_unregister(&ip6gre_link_ops);
2330 rtnl_link_failed:
2331 	inet6_del_protocol(&ip6gre_protocol, IPPROTO_GRE);
2332 add_proto_failed:
2333 	unregister_pernet_device(&ip6gre_net_ops);
2334 	goto out;
2335 }
2336 
2337 static void __exit ip6gre_fini(void)
2338 {
2339 	rtnl_link_unregister(&ip6gre_tap_ops);
2340 	rtnl_link_unregister(&ip6gre_link_ops);
2341 	rtnl_link_unregister(&ip6erspan_tap_ops);
2342 	inet6_del_protocol(&ip6gre_protocol, IPPROTO_GRE);
2343 	unregister_pernet_device(&ip6gre_net_ops);
2344 }
2345 
2346 module_init(ip6gre_init);
2347 module_exit(ip6gre_fini);
2348 MODULE_LICENSE("GPL");
2349 MODULE_AUTHOR("D. Kozlov (xeb@mail.ru)");
2350 MODULE_DESCRIPTION("GRE over IPv6 tunneling device");
2351 MODULE_ALIAS_RTNL_LINK("ip6gre");
2352 MODULE_ALIAS_RTNL_LINK("ip6gretap");
2353 MODULE_ALIAS_RTNL_LINK("ip6erspan");
2354 MODULE_ALIAS_NETDEV("ip6gre0");
2355