xref: /linux/net/ipv6/ip6_gre.c (revision 8be4d31cb8aaeea27bde4b7ddb26e28a89062ebf)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *	GRE over IPv6 protocol decoder.
4  *
5  *	Authors: Dmitry Kozlov (xeb@mail.ru)
6  */
7 
8 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
9 
10 #include <linux/capability.h>
11 #include <linux/module.h>
12 #include <linux/types.h>
13 #include <linux/kernel.h>
14 #include <linux/slab.h>
15 #include <linux/uaccess.h>
16 #include <linux/skbuff.h>
17 #include <linux/netdevice.h>
18 #include <linux/in.h>
19 #include <linux/tcp.h>
20 #include <linux/udp.h>
21 #include <linux/if_arp.h>
22 #include <linux/init.h>
23 #include <linux/in6.h>
24 #include <linux/inetdevice.h>
25 #include <linux/igmp.h>
26 #include <linux/netfilter_ipv4.h>
27 #include <linux/etherdevice.h>
28 #include <linux/if_ether.h>
29 #include <linux/hash.h>
30 #include <linux/if_tunnel.h>
31 #include <linux/ip6_tunnel.h>
32 
33 #include <net/sock.h>
34 #include <net/ip.h>
35 #include <net/ip_tunnels.h>
36 #include <net/icmp.h>
37 #include <net/protocol.h>
38 #include <net/addrconf.h>
39 #include <net/arp.h>
40 #include <net/checksum.h>
41 #include <net/dsfield.h>
42 #include <net/inet_ecn.h>
43 #include <net/xfrm.h>
44 #include <net/net_namespace.h>
45 #include <net/netns/generic.h>
46 #include <net/netdev_lock.h>
47 #include <net/rtnetlink.h>
48 
49 #include <net/ipv6.h>
50 #include <net/ip6_fib.h>
51 #include <net/ip6_route.h>
52 #include <net/ip6_tunnel.h>
53 #include <net/gre.h>
54 #include <net/erspan.h>
55 #include <net/dst_metadata.h>
56 
57 
58 static bool log_ecn_error = true;
59 module_param(log_ecn_error, bool, 0644);
60 MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN");
61 
62 #define IP6_GRE_HASH_SIZE_SHIFT  5
63 #define IP6_GRE_HASH_SIZE (1 << IP6_GRE_HASH_SIZE_SHIFT)
64 
65 static unsigned int ip6gre_net_id __read_mostly;
66 struct ip6gre_net {
67 	struct ip6_tnl __rcu *tunnels[4][IP6_GRE_HASH_SIZE];
68 
69 	struct ip6_tnl __rcu *collect_md_tun;
70 	struct ip6_tnl __rcu *collect_md_tun_erspan;
71 	struct net_device *fb_tunnel_dev;
72 };
73 
74 static struct rtnl_link_ops ip6gre_link_ops __read_mostly;
75 static struct rtnl_link_ops ip6gre_tap_ops __read_mostly;
76 static struct rtnl_link_ops ip6erspan_tap_ops __read_mostly;
77 static int ip6gre_tunnel_init(struct net_device *dev);
78 static void ip6gre_tunnel_setup(struct net_device *dev);
79 static void ip6gre_tunnel_link(struct ip6gre_net *ign, struct ip6_tnl *t);
80 static void ip6gre_tnl_link_config(struct ip6_tnl *t, int set_mtu);
81 static void ip6erspan_tnl_link_config(struct ip6_tnl *t, int set_mtu);
82 
83 /* Tunnel hash table */
84 
85 /*
86    4 hash tables:
87 
88    3: (remote,local)
89    2: (remote,*)
90    1: (*,local)
91    0: (*,*)
92 
93    We require exact key match i.e. if a key is present in packet
94    it will match only tunnel with the same key; if it is not present,
95    it will match only keyless tunnel.
96 
97    All keysless packets, if not matched configured keyless tunnels
98    will match fallback tunnel.
99  */
100 
101 #define HASH_KEY(key) (((__force u32)key^((__force u32)key>>4))&(IP6_GRE_HASH_SIZE - 1))
102 static u32 HASH_ADDR(const struct in6_addr *addr)
103 {
104 	u32 hash = ipv6_addr_hash(addr);
105 
106 	return hash_32(hash, IP6_GRE_HASH_SIZE_SHIFT);
107 }
108 
109 #define tunnels_r_l	tunnels[3]
110 #define tunnels_r	tunnels[2]
111 #define tunnels_l	tunnels[1]
112 #define tunnels_wc	tunnels[0]
113 
114 static bool ip6gre_tunnel_match(struct ip6_tnl *t, int dev_type, int link,
115 				int *cand_score, struct ip6_tnl **ret)
116 {
117 	int score = 0;
118 
119 	if (t->dev->type != ARPHRD_IP6GRE &&
120 	    t->dev->type != dev_type)
121 		return false;
122 
123 	if (t->parms.link != link)
124 		score |= 1;
125 	if (t->dev->type != dev_type)
126 		score |= 2;
127 	if (score == 0) {
128 		*ret = t;
129 		return true;
130 	}
131 
132 	if (score < *cand_score) {
133 		*ret = t;
134 		*cand_score = score;
135 	}
136 	return false;
137 }
138 
139 /* Given src, dst and key, find appropriate for input tunnel. */
140 static struct ip6_tnl *ip6gre_tunnel_lookup(struct net_device *dev,
141 		const struct in6_addr *remote, const struct in6_addr *local,
142 		__be32 key, __be16 gre_proto)
143 {
144 	struct net *net = dev_net(dev);
145 	int link = dev->ifindex;
146 	unsigned int h0 = HASH_ADDR(remote);
147 	unsigned int h1 = HASH_KEY(key);
148 	struct ip6_tnl *t, *cand = NULL;
149 	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
150 	int dev_type = (gre_proto == htons(ETH_P_TEB) ||
151 			gre_proto == htons(ETH_P_ERSPAN) ||
152 			gre_proto == htons(ETH_P_ERSPAN2)) ?
153 		       ARPHRD_ETHER : ARPHRD_IP6GRE;
154 	struct net_device *ndev;
155 	int cand_score = 4;
156 
157 	for_each_ip_tunnel_rcu(t, ign->tunnels_r_l[h0 ^ h1]) {
158 		if (!ipv6_addr_equal(local, &t->parms.laddr) ||
159 		    !ipv6_addr_equal(remote, &t->parms.raddr) ||
160 		    key != t->parms.i_key ||
161 		    !(t->dev->flags & IFF_UP))
162 			continue;
163 
164 		if (ip6gre_tunnel_match(t, dev_type, link, &cand_score, &cand))
165 			return cand;
166 	}
167 
168 	for_each_ip_tunnel_rcu(t, ign->tunnels_r[h0 ^ h1]) {
169 		if (!ipv6_addr_equal(remote, &t->parms.raddr) ||
170 		    key != t->parms.i_key ||
171 		    !(t->dev->flags & IFF_UP))
172 			continue;
173 
174 		if (ip6gre_tunnel_match(t, dev_type, link, &cand_score, &cand))
175 			return cand;
176 	}
177 
178 	for_each_ip_tunnel_rcu(t, ign->tunnels_l[h1]) {
179 		if ((!ipv6_addr_equal(local, &t->parms.laddr) &&
180 			  (!ipv6_addr_equal(local, &t->parms.raddr) ||
181 				 !ipv6_addr_is_multicast(local))) ||
182 		    key != t->parms.i_key ||
183 		    !(t->dev->flags & IFF_UP))
184 			continue;
185 
186 		if (ip6gre_tunnel_match(t, dev_type, link, &cand_score, &cand))
187 			return cand;
188 	}
189 
190 	for_each_ip_tunnel_rcu(t, ign->tunnels_wc[h1]) {
191 		if (t->parms.i_key != key ||
192 		    !(t->dev->flags & IFF_UP))
193 			continue;
194 
195 		if (ip6gre_tunnel_match(t, dev_type, link, &cand_score, &cand))
196 			return cand;
197 	}
198 
199 	if (cand)
200 		return cand;
201 
202 	if (gre_proto == htons(ETH_P_ERSPAN) ||
203 	    gre_proto == htons(ETH_P_ERSPAN2))
204 		t = rcu_dereference(ign->collect_md_tun_erspan);
205 	else
206 		t = rcu_dereference(ign->collect_md_tun);
207 
208 	if (t && t->dev->flags & IFF_UP)
209 		return t;
210 
211 	ndev = READ_ONCE(ign->fb_tunnel_dev);
212 	if (ndev && ndev->flags & IFF_UP)
213 		return netdev_priv(ndev);
214 
215 	return NULL;
216 }
217 
218 static struct ip6_tnl __rcu **__ip6gre_bucket(struct ip6gre_net *ign,
219 		const struct __ip6_tnl_parm *p)
220 {
221 	const struct in6_addr *remote = &p->raddr;
222 	const struct in6_addr *local = &p->laddr;
223 	unsigned int h = HASH_KEY(p->i_key);
224 	int prio = 0;
225 
226 	if (!ipv6_addr_any(local))
227 		prio |= 1;
228 	if (!ipv6_addr_any(remote) && !ipv6_addr_is_multicast(remote)) {
229 		prio |= 2;
230 		h ^= HASH_ADDR(remote);
231 	}
232 
233 	return &ign->tunnels[prio][h];
234 }
235 
236 static void ip6gre_tunnel_link_md(struct ip6gre_net *ign, struct ip6_tnl *t)
237 {
238 	if (t->parms.collect_md)
239 		rcu_assign_pointer(ign->collect_md_tun, t);
240 }
241 
242 static void ip6erspan_tunnel_link_md(struct ip6gre_net *ign, struct ip6_tnl *t)
243 {
244 	if (t->parms.collect_md)
245 		rcu_assign_pointer(ign->collect_md_tun_erspan, t);
246 }
247 
248 static void ip6gre_tunnel_unlink_md(struct ip6gre_net *ign, struct ip6_tnl *t)
249 {
250 	if (t->parms.collect_md)
251 		rcu_assign_pointer(ign->collect_md_tun, NULL);
252 }
253 
254 static void ip6erspan_tunnel_unlink_md(struct ip6gre_net *ign,
255 				       struct ip6_tnl *t)
256 {
257 	if (t->parms.collect_md)
258 		rcu_assign_pointer(ign->collect_md_tun_erspan, NULL);
259 }
260 
261 static inline struct ip6_tnl __rcu **ip6gre_bucket(struct ip6gre_net *ign,
262 		const struct ip6_tnl *t)
263 {
264 	return __ip6gre_bucket(ign, &t->parms);
265 }
266 
267 static void ip6gre_tunnel_link(struct ip6gre_net *ign, struct ip6_tnl *t)
268 {
269 	struct ip6_tnl __rcu **tp = ip6gre_bucket(ign, t);
270 
271 	rcu_assign_pointer(t->next, rtnl_dereference(*tp));
272 	rcu_assign_pointer(*tp, t);
273 }
274 
275 static void ip6gre_tunnel_unlink(struct ip6gre_net *ign, struct ip6_tnl *t)
276 {
277 	struct ip6_tnl __rcu **tp;
278 	struct ip6_tnl *iter;
279 
280 	for (tp = ip6gre_bucket(ign, t);
281 	     (iter = rtnl_dereference(*tp)) != NULL;
282 	     tp = &iter->next) {
283 		if (t == iter) {
284 			rcu_assign_pointer(*tp, t->next);
285 			break;
286 		}
287 	}
288 }
289 
290 static struct ip6_tnl *ip6gre_tunnel_find(struct net *net,
291 					   const struct __ip6_tnl_parm *parms,
292 					   int type)
293 {
294 	const struct in6_addr *remote = &parms->raddr;
295 	const struct in6_addr *local = &parms->laddr;
296 	__be32 key = parms->i_key;
297 	int link = parms->link;
298 	struct ip6_tnl *t;
299 	struct ip6_tnl __rcu **tp;
300 	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
301 
302 	for (tp = __ip6gre_bucket(ign, parms);
303 	     (t = rtnl_dereference(*tp)) != NULL;
304 	     tp = &t->next)
305 		if (ipv6_addr_equal(local, &t->parms.laddr) &&
306 		    ipv6_addr_equal(remote, &t->parms.raddr) &&
307 		    key == t->parms.i_key &&
308 		    link == t->parms.link &&
309 		    type == t->dev->type)
310 			break;
311 
312 	return t;
313 }
314 
315 static struct ip6_tnl *ip6gre_tunnel_locate(struct net *net,
316 		const struct __ip6_tnl_parm *parms, int create)
317 {
318 	struct ip6_tnl *t, *nt;
319 	struct net_device *dev;
320 	char name[IFNAMSIZ];
321 	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
322 
323 	t = ip6gre_tunnel_find(net, parms, ARPHRD_IP6GRE);
324 	if (t && create)
325 		return NULL;
326 	if (t || !create)
327 		return t;
328 
329 	if (parms->name[0]) {
330 		if (!dev_valid_name(parms->name))
331 			return NULL;
332 		strscpy(name, parms->name, IFNAMSIZ);
333 	} else {
334 		strcpy(name, "ip6gre%d");
335 	}
336 	dev = alloc_netdev(sizeof(*t), name, NET_NAME_UNKNOWN,
337 			   ip6gre_tunnel_setup);
338 	if (!dev)
339 		return NULL;
340 
341 	dev_net_set(dev, net);
342 
343 	nt = netdev_priv(dev);
344 	nt->parms = *parms;
345 	dev->rtnl_link_ops = &ip6gre_link_ops;
346 
347 	nt->dev = dev;
348 	nt->net = dev_net(dev);
349 
350 	if (register_netdevice(dev) < 0)
351 		goto failed_free;
352 
353 	ip6gre_tnl_link_config(nt, 1);
354 	ip6gre_tunnel_link(ign, nt);
355 	return nt;
356 
357 failed_free:
358 	free_netdev(dev);
359 	return NULL;
360 }
361 
362 static void ip6erspan_tunnel_uninit(struct net_device *dev)
363 {
364 	struct ip6_tnl *t = netdev_priv(dev);
365 	struct ip6gre_net *ign = net_generic(t->net, ip6gre_net_id);
366 
367 	ip6erspan_tunnel_unlink_md(ign, t);
368 	ip6gre_tunnel_unlink(ign, t);
369 	dst_cache_reset(&t->dst_cache);
370 	netdev_put(dev, &t->dev_tracker);
371 }
372 
373 static void ip6gre_tunnel_uninit(struct net_device *dev)
374 {
375 	struct ip6_tnl *t = netdev_priv(dev);
376 	struct ip6gre_net *ign = net_generic(t->net, ip6gre_net_id);
377 
378 	ip6gre_tunnel_unlink_md(ign, t);
379 	ip6gre_tunnel_unlink(ign, t);
380 	if (ign->fb_tunnel_dev == dev)
381 		WRITE_ONCE(ign->fb_tunnel_dev, NULL);
382 	dst_cache_reset(&t->dst_cache);
383 	netdev_put(dev, &t->dev_tracker);
384 }
385 
386 
387 static int ip6gre_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
388 		       u8 type, u8 code, int offset, __be32 info)
389 {
390 	struct net *net = dev_net(skb->dev);
391 	const struct ipv6hdr *ipv6h;
392 	struct tnl_ptk_info tpi;
393 	struct ip6_tnl *t;
394 
395 	if (gre_parse_header(skb, &tpi, NULL, htons(ETH_P_IPV6),
396 			     offset) < 0)
397 		return -EINVAL;
398 
399 	ipv6h = (const struct ipv6hdr *)skb->data;
400 	t = ip6gre_tunnel_lookup(skb->dev, &ipv6h->daddr, &ipv6h->saddr,
401 				 tpi.key, tpi.proto);
402 	if (!t)
403 		return -ENOENT;
404 
405 	switch (type) {
406 	case ICMPV6_DEST_UNREACH:
407 		net_dbg_ratelimited("%s: Path to destination invalid or inactive!\n",
408 				    t->parms.name);
409 		if (code != ICMPV6_PORT_UNREACH)
410 			break;
411 		return 0;
412 	case ICMPV6_TIME_EXCEED:
413 		if (code == ICMPV6_EXC_HOPLIMIT) {
414 			net_dbg_ratelimited("%s: Too small hop limit or routing loop in tunnel!\n",
415 					    t->parms.name);
416 			break;
417 		}
418 		return 0;
419 	case ICMPV6_PARAMPROB: {
420 		struct ipv6_tlv_tnl_enc_lim *tel;
421 		__u32 teli;
422 
423 		teli = 0;
424 		if (code == ICMPV6_HDR_FIELD)
425 			teli = ip6_tnl_parse_tlv_enc_lim(skb, skb->data);
426 
427 		if (teli && teli == be32_to_cpu(info) - 2) {
428 			tel = (struct ipv6_tlv_tnl_enc_lim *) &skb->data[teli];
429 			if (tel->encap_limit == 0) {
430 				net_dbg_ratelimited("%s: Too small encapsulation limit or routing loop in tunnel!\n",
431 						    t->parms.name);
432 			}
433 		} else {
434 			net_dbg_ratelimited("%s: Recipient unable to parse tunneled packet!\n",
435 					    t->parms.name);
436 		}
437 		return 0;
438 	}
439 	case ICMPV6_PKT_TOOBIG:
440 		ip6_update_pmtu(skb, net, info, 0, 0, sock_net_uid(net, NULL));
441 		return 0;
442 	case NDISC_REDIRECT:
443 		ip6_redirect(skb, net, skb->dev->ifindex, 0,
444 			     sock_net_uid(net, NULL));
445 		return 0;
446 	}
447 
448 	if (time_before(jiffies, t->err_time + IP6TUNNEL_ERR_TIMEO))
449 		t->err_count++;
450 	else
451 		t->err_count = 1;
452 	t->err_time = jiffies;
453 
454 	return 0;
455 }
456 
457 static int ip6gre_rcv(struct sk_buff *skb, const struct tnl_ptk_info *tpi)
458 {
459 	const struct ipv6hdr *ipv6h;
460 	struct ip6_tnl *tunnel;
461 
462 	ipv6h = ipv6_hdr(skb);
463 	tunnel = ip6gre_tunnel_lookup(skb->dev,
464 				      &ipv6h->saddr, &ipv6h->daddr, tpi->key,
465 				      tpi->proto);
466 	if (tunnel) {
467 		if (tunnel->parms.collect_md) {
468 			IP_TUNNEL_DECLARE_FLAGS(flags);
469 			struct metadata_dst *tun_dst;
470 			__be64 tun_id;
471 
472 			ip_tunnel_flags_copy(flags, tpi->flags);
473 			tun_id = key32_to_tunnel_id(tpi->key);
474 
475 			tun_dst = ipv6_tun_rx_dst(skb, flags, tun_id, 0);
476 			if (!tun_dst)
477 				return PACKET_REJECT;
478 
479 			ip6_tnl_rcv(tunnel, skb, tpi, tun_dst, log_ecn_error);
480 		} else {
481 			ip6_tnl_rcv(tunnel, skb, tpi, NULL, log_ecn_error);
482 		}
483 
484 		return PACKET_RCVD;
485 	}
486 
487 	return PACKET_REJECT;
488 }
489 
490 static int ip6erspan_rcv(struct sk_buff *skb,
491 			 struct tnl_ptk_info *tpi,
492 			 int gre_hdr_len)
493 {
494 	struct erspan_base_hdr *ershdr;
495 	const struct ipv6hdr *ipv6h;
496 	struct erspan_md2 *md2;
497 	struct ip6_tnl *tunnel;
498 	u8 ver;
499 
500 	if (unlikely(!pskb_may_pull(skb, sizeof(*ershdr))))
501 		return PACKET_REJECT;
502 
503 	ipv6h = ipv6_hdr(skb);
504 	ershdr = (struct erspan_base_hdr *)skb->data;
505 	ver = ershdr->ver;
506 
507 	tunnel = ip6gre_tunnel_lookup(skb->dev,
508 				      &ipv6h->saddr, &ipv6h->daddr, tpi->key,
509 				      tpi->proto);
510 	if (tunnel) {
511 		int len = erspan_hdr_len(ver);
512 
513 		if (unlikely(!pskb_may_pull(skb, len)))
514 			return PACKET_REJECT;
515 
516 		if (__iptunnel_pull_header(skb, len,
517 					   htons(ETH_P_TEB),
518 					   false, false) < 0)
519 			return PACKET_REJECT;
520 
521 		if (tunnel->parms.collect_md) {
522 			struct erspan_metadata *pkt_md, *md;
523 			IP_TUNNEL_DECLARE_FLAGS(flags);
524 			struct metadata_dst *tun_dst;
525 			struct ip_tunnel_info *info;
526 			unsigned char *gh;
527 			__be64 tun_id;
528 
529 			__set_bit(IP_TUNNEL_KEY_BIT, tpi->flags);
530 			ip_tunnel_flags_copy(flags, tpi->flags);
531 			tun_id = key32_to_tunnel_id(tpi->key);
532 
533 			tun_dst = ipv6_tun_rx_dst(skb, flags, tun_id,
534 						  sizeof(*md));
535 			if (!tun_dst)
536 				return PACKET_REJECT;
537 
538 			/* skb can be uncloned in __iptunnel_pull_header, so
539 			 * old pkt_md is no longer valid and we need to reset
540 			 * it
541 			 */
542 			gh = skb_network_header(skb) +
543 			     skb_network_header_len(skb);
544 			pkt_md = (struct erspan_metadata *)(gh + gre_hdr_len +
545 							    sizeof(*ershdr));
546 			info = &tun_dst->u.tun_info;
547 			md = ip_tunnel_info_opts(info);
548 			md->version = ver;
549 			md2 = &md->u.md2;
550 			memcpy(md2, pkt_md, ver == 1 ? ERSPAN_V1_MDSIZE :
551 						       ERSPAN_V2_MDSIZE);
552 			__set_bit(IP_TUNNEL_ERSPAN_OPT_BIT,
553 				  info->key.tun_flags);
554 			info->options_len = sizeof(*md);
555 
556 			ip6_tnl_rcv(tunnel, skb, tpi, tun_dst, log_ecn_error);
557 
558 		} else {
559 			ip6_tnl_rcv(tunnel, skb, tpi, NULL, log_ecn_error);
560 		}
561 
562 		return PACKET_RCVD;
563 	}
564 
565 	return PACKET_REJECT;
566 }
567 
568 static int gre_rcv(struct sk_buff *skb)
569 {
570 	struct tnl_ptk_info tpi;
571 	bool csum_err = false;
572 	int hdr_len;
573 
574 	hdr_len = gre_parse_header(skb, &tpi, &csum_err, htons(ETH_P_IPV6), 0);
575 	if (hdr_len < 0)
576 		goto drop;
577 
578 	if (iptunnel_pull_header(skb, hdr_len, tpi.proto, false))
579 		goto drop;
580 
581 	if (unlikely(tpi.proto == htons(ETH_P_ERSPAN) ||
582 		     tpi.proto == htons(ETH_P_ERSPAN2))) {
583 		if (ip6erspan_rcv(skb, &tpi, hdr_len) == PACKET_RCVD)
584 			return 0;
585 		goto out;
586 	}
587 
588 	if (ip6gre_rcv(skb, &tpi) == PACKET_RCVD)
589 		return 0;
590 
591 out:
592 	icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0);
593 drop:
594 	kfree_skb(skb);
595 	return 0;
596 }
597 
598 static int gre_handle_offloads(struct sk_buff *skb, bool csum)
599 {
600 	return iptunnel_handle_offloads(skb,
601 					csum ? SKB_GSO_GRE_CSUM : SKB_GSO_GRE);
602 }
603 
604 static void prepare_ip6gre_xmit_ipv4(struct sk_buff *skb,
605 				     struct net_device *dev,
606 				     struct flowi6 *fl6, __u8 *dsfield,
607 				     int *encap_limit)
608 {
609 	const struct iphdr *iph = ip_hdr(skb);
610 	struct ip6_tnl *t = netdev_priv(dev);
611 
612 	if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
613 		*encap_limit = t->parms.encap_limit;
614 
615 	memcpy(fl6, &t->fl.u.ip6, sizeof(*fl6));
616 
617 	if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
618 		*dsfield = ipv4_get_dsfield(iph);
619 	else
620 		*dsfield = ip6_tclass(t->parms.flowinfo);
621 
622 	if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
623 		fl6->flowi6_mark = skb->mark;
624 	else
625 		fl6->flowi6_mark = t->parms.fwmark;
626 
627 	fl6->flowi6_uid = sock_net_uid(dev_net(dev), NULL);
628 }
629 
630 static int prepare_ip6gre_xmit_ipv6(struct sk_buff *skb,
631 				    struct net_device *dev,
632 				    struct flowi6 *fl6, __u8 *dsfield,
633 				    int *encap_limit)
634 {
635 	struct ipv6hdr *ipv6h;
636 	struct ip6_tnl *t = netdev_priv(dev);
637 	__u16 offset;
638 
639 	offset = ip6_tnl_parse_tlv_enc_lim(skb, skb_network_header(skb));
640 	/* ip6_tnl_parse_tlv_enc_lim() might have reallocated skb->head */
641 	ipv6h = ipv6_hdr(skb);
642 
643 	if (offset > 0) {
644 		struct ipv6_tlv_tnl_enc_lim *tel;
645 
646 		tel = (struct ipv6_tlv_tnl_enc_lim *)&skb_network_header(skb)[offset];
647 		if (tel->encap_limit == 0) {
648 			icmpv6_ndo_send(skb, ICMPV6_PARAMPROB,
649 					ICMPV6_HDR_FIELD, offset + 2);
650 			return -1;
651 		}
652 		*encap_limit = tel->encap_limit - 1;
653 	} else if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) {
654 		*encap_limit = t->parms.encap_limit;
655 	}
656 
657 	memcpy(fl6, &t->fl.u.ip6, sizeof(*fl6));
658 
659 	if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
660 		*dsfield = ipv6_get_dsfield(ipv6h);
661 	else
662 		*dsfield = ip6_tclass(t->parms.flowinfo);
663 
664 	if (t->parms.flags & IP6_TNL_F_USE_ORIG_FLOWLABEL)
665 		fl6->flowlabel |= ip6_flowlabel(ipv6h);
666 
667 	if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
668 		fl6->flowi6_mark = skb->mark;
669 	else
670 		fl6->flowi6_mark = t->parms.fwmark;
671 
672 	fl6->flowi6_uid = sock_net_uid(dev_net(dev), NULL);
673 
674 	return 0;
675 }
676 
677 static int prepare_ip6gre_xmit_other(struct sk_buff *skb,
678 				     struct net_device *dev,
679 				     struct flowi6 *fl6, __u8 *dsfield,
680 				     int *encap_limit)
681 {
682 	struct ip6_tnl *t = netdev_priv(dev);
683 
684 	if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
685 		*encap_limit = t->parms.encap_limit;
686 
687 	memcpy(fl6, &t->fl.u.ip6, sizeof(*fl6));
688 
689 	if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
690 		*dsfield = 0;
691 	else
692 		*dsfield = ip6_tclass(t->parms.flowinfo);
693 
694 	if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
695 		fl6->flowi6_mark = skb->mark;
696 	else
697 		fl6->flowi6_mark = t->parms.fwmark;
698 
699 	fl6->flowi6_uid = sock_net_uid(dev_net(dev), NULL);
700 
701 	return 0;
702 }
703 
704 static struct ip_tunnel_info *skb_tunnel_info_txcheck(struct sk_buff *skb)
705 {
706 	struct ip_tunnel_info *tun_info;
707 
708 	tun_info = skb_tunnel_info(skb);
709 	if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX)))
710 		return ERR_PTR(-EINVAL);
711 
712 	return tun_info;
713 }
714 
715 static netdev_tx_t __gre6_xmit(struct sk_buff *skb,
716 			       struct net_device *dev, __u8 dsfield,
717 			       struct flowi6 *fl6, int encap_limit,
718 			       __u32 *pmtu, __be16 proto)
719 {
720 	struct ip6_tnl *tunnel = netdev_priv(dev);
721 	IP_TUNNEL_DECLARE_FLAGS(flags);
722 	__be16 protocol;
723 
724 	if (dev->type == ARPHRD_ETHER)
725 		IPCB(skb)->flags = 0;
726 
727 	if (dev->header_ops && dev->type == ARPHRD_IP6GRE)
728 		fl6->daddr = ((struct ipv6hdr *)skb->data)->daddr;
729 	else
730 		fl6->daddr = tunnel->parms.raddr;
731 
732 	/* Push GRE header. */
733 	protocol = (dev->type == ARPHRD_ETHER) ? htons(ETH_P_TEB) : proto;
734 
735 	if (tunnel->parms.collect_md) {
736 		struct ip_tunnel_info *tun_info;
737 		const struct ip_tunnel_key *key;
738 		int tun_hlen;
739 
740 		tun_info = skb_tunnel_info_txcheck(skb);
741 		if (IS_ERR(tun_info) ||
742 		    unlikely(ip_tunnel_info_af(tun_info) != AF_INET6))
743 			return -EINVAL;
744 
745 		key = &tun_info->key;
746 		memset(fl6, 0, sizeof(*fl6));
747 		fl6->flowi6_proto = IPPROTO_GRE;
748 		fl6->daddr = key->u.ipv6.dst;
749 		fl6->flowlabel = key->label;
750 		fl6->flowi6_uid = sock_net_uid(dev_net(dev), NULL);
751 		fl6->fl6_gre_key = tunnel_id_to_key32(key->tun_id);
752 
753 		dsfield = key->tos;
754 		ip_tunnel_flags_zero(flags);
755 		__set_bit(IP_TUNNEL_CSUM_BIT, flags);
756 		__set_bit(IP_TUNNEL_KEY_BIT, flags);
757 		__set_bit(IP_TUNNEL_SEQ_BIT, flags);
758 		ip_tunnel_flags_and(flags, flags, key->tun_flags);
759 		tun_hlen = gre_calc_hlen(flags);
760 
761 		if (skb_cow_head(skb, dev->needed_headroom ?: tun_hlen + tunnel->encap_hlen))
762 			return -ENOMEM;
763 
764 		gre_build_header(skb, tun_hlen,
765 				 flags, protocol,
766 				 tunnel_id_to_key32(tun_info->key.tun_id),
767 				 test_bit(IP_TUNNEL_SEQ_BIT, flags) ?
768 				 htonl(atomic_fetch_inc(&tunnel->o_seqno)) :
769 				 0);
770 
771 	} else {
772 		if (skb_cow_head(skb, dev->needed_headroom ?: tunnel->hlen))
773 			return -ENOMEM;
774 
775 		ip_tunnel_flags_copy(flags, tunnel->parms.o_flags);
776 
777 		gre_build_header(skb, tunnel->tun_hlen, flags,
778 				 protocol, tunnel->parms.o_key,
779 				 test_bit(IP_TUNNEL_SEQ_BIT, flags) ?
780 				 htonl(atomic_fetch_inc(&tunnel->o_seqno)) :
781 				 0);
782 	}
783 
784 	return ip6_tnl_xmit(skb, dev, dsfield, fl6, encap_limit, pmtu,
785 			    NEXTHDR_GRE);
786 }
787 
788 static inline int ip6gre_xmit_ipv4(struct sk_buff *skb, struct net_device *dev)
789 {
790 	struct ip6_tnl *t = netdev_priv(dev);
791 	int encap_limit = -1;
792 	struct flowi6 fl6;
793 	__u8 dsfield = 0;
794 	__u32 mtu;
795 	int err;
796 
797 	memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
798 
799 	if (!t->parms.collect_md)
800 		prepare_ip6gre_xmit_ipv4(skb, dev, &fl6,
801 					 &dsfield, &encap_limit);
802 
803 	err = gre_handle_offloads(skb, test_bit(IP_TUNNEL_CSUM_BIT,
804 						t->parms.o_flags));
805 	if (err)
806 		return -1;
807 
808 	err = __gre6_xmit(skb, dev, dsfield, &fl6, encap_limit, &mtu,
809 			  skb->protocol);
810 	if (err != 0) {
811 		/* XXX: send ICMP error even if DF is not set. */
812 		if (err == -EMSGSIZE)
813 			icmp_ndo_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
814 				      htonl(mtu));
815 		return -1;
816 	}
817 
818 	return 0;
819 }
820 
821 static inline int ip6gre_xmit_ipv6(struct sk_buff *skb, struct net_device *dev)
822 {
823 	struct ip6_tnl *t = netdev_priv(dev);
824 	struct ipv6hdr *ipv6h = ipv6_hdr(skb);
825 	int encap_limit = -1;
826 	struct flowi6 fl6;
827 	__u8 dsfield = 0;
828 	__u32 mtu;
829 	int err;
830 
831 	if (ipv6_addr_equal(&t->parms.raddr, &ipv6h->saddr))
832 		return -1;
833 
834 	if (!t->parms.collect_md &&
835 	    prepare_ip6gre_xmit_ipv6(skb, dev, &fl6, &dsfield, &encap_limit))
836 		return -1;
837 
838 	if (gre_handle_offloads(skb, test_bit(IP_TUNNEL_CSUM_BIT,
839 					      t->parms.o_flags)))
840 		return -1;
841 
842 	err = __gre6_xmit(skb, dev, dsfield, &fl6, encap_limit,
843 			  &mtu, skb->protocol);
844 	if (err != 0) {
845 		if (err == -EMSGSIZE)
846 			icmpv6_ndo_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
847 		return -1;
848 	}
849 
850 	return 0;
851 }
852 
853 static int ip6gre_xmit_other(struct sk_buff *skb, struct net_device *dev)
854 {
855 	struct ip6_tnl *t = netdev_priv(dev);
856 	int encap_limit = -1;
857 	struct flowi6 fl6;
858 	__u8 dsfield = 0;
859 	__u32 mtu;
860 	int err;
861 
862 	if (!t->parms.collect_md &&
863 	    prepare_ip6gre_xmit_other(skb, dev, &fl6, &dsfield, &encap_limit))
864 		return -1;
865 
866 	err = gre_handle_offloads(skb, test_bit(IP_TUNNEL_CSUM_BIT,
867 						t->parms.o_flags));
868 	if (err)
869 		return err;
870 	err = __gre6_xmit(skb, dev, dsfield, &fl6, encap_limit, &mtu, skb->protocol);
871 
872 	return err;
873 }
874 
875 static netdev_tx_t ip6gre_tunnel_xmit(struct sk_buff *skb,
876 	struct net_device *dev)
877 {
878 	struct ip6_tnl *t = netdev_priv(dev);
879 	__be16 payload_protocol;
880 	int ret;
881 
882 	if (!pskb_inet_may_pull(skb))
883 		goto tx_err;
884 
885 	if (!ip6_tnl_xmit_ctl(t, &t->parms.laddr, &t->parms.raddr))
886 		goto tx_err;
887 
888 	payload_protocol = skb_protocol(skb, true);
889 	switch (payload_protocol) {
890 	case htons(ETH_P_IP):
891 		ret = ip6gre_xmit_ipv4(skb, dev);
892 		break;
893 	case htons(ETH_P_IPV6):
894 		ret = ip6gre_xmit_ipv6(skb, dev);
895 		break;
896 	default:
897 		ret = ip6gre_xmit_other(skb, dev);
898 		break;
899 	}
900 
901 	if (ret < 0)
902 		goto tx_err;
903 
904 	return NETDEV_TX_OK;
905 
906 tx_err:
907 	if (!t->parms.collect_md || !IS_ERR(skb_tunnel_info_txcheck(skb)))
908 		DEV_STATS_INC(dev, tx_errors);
909 	DEV_STATS_INC(dev, 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 ip_tunnel_info *tun_info = NULL;
918 	struct ip6_tnl *t = netdev_priv(dev);
919 	struct dst_entry *dst = skb_dst(skb);
920 	IP_TUNNEL_DECLARE_FLAGS(flags) = { };
921 	bool truncate = false;
922 	int encap_limit = -1;
923 	__u8 dsfield = false;
924 	struct flowi6 fl6;
925 	int err = -EINVAL;
926 	__be16 proto;
927 	__u32 mtu;
928 	int nhoff;
929 
930 	if (!pskb_inet_may_pull(skb))
931 		goto tx_err;
932 
933 	if (!ip6_tnl_xmit_ctl(t, &t->parms.laddr, &t->parms.raddr))
934 		goto tx_err;
935 
936 	if (gre_handle_offloads(skb, false))
937 		goto tx_err;
938 
939 	if (skb->len > dev->mtu + dev->hard_header_len) {
940 		if (pskb_trim(skb, dev->mtu + dev->hard_header_len))
941 			goto tx_err;
942 		truncate = true;
943 	}
944 
945 	nhoff = skb_network_offset(skb);
946 	if (skb->protocol == htons(ETH_P_IP) &&
947 	    (ntohs(ip_hdr(skb)->tot_len) > skb->len - nhoff))
948 		truncate = true;
949 
950 	if (skb->protocol == htons(ETH_P_IPV6)) {
951 		int thoff;
952 
953 		if (skb_transport_header_was_set(skb))
954 			thoff = skb_transport_offset(skb);
955 		else
956 			thoff = nhoff + sizeof(struct ipv6hdr);
957 		if (ntohs(ipv6_hdr(skb)->payload_len) > skb->len - thoff)
958 			truncate = true;
959 	}
960 
961 	if (skb_cow_head(skb, dev->needed_headroom ?: t->hlen))
962 		goto tx_err;
963 
964 	__clear_bit(IP_TUNNEL_KEY_BIT, t->parms.o_flags);
965 	IPCB(skb)->flags = 0;
966 
967 	/* For collect_md mode, derive fl6 from the tunnel key,
968 	 * for native mode, call prepare_ip6gre_xmit_{ipv4,ipv6}.
969 	 */
970 	if (t->parms.collect_md) {
971 		const struct ip_tunnel_key *key;
972 		struct erspan_metadata *md;
973 		__be32 tun_id;
974 
975 		tun_info = skb_tunnel_info_txcheck(skb);
976 		if (IS_ERR(tun_info) ||
977 		    unlikely(ip_tunnel_info_af(tun_info) != AF_INET6))
978 			goto tx_err;
979 
980 		key = &tun_info->key;
981 		memset(&fl6, 0, sizeof(fl6));
982 		fl6.flowi6_proto = IPPROTO_GRE;
983 		fl6.daddr = key->u.ipv6.dst;
984 		fl6.flowlabel = key->label;
985 		fl6.flowi6_uid = sock_net_uid(dev_net(dev), NULL);
986 		fl6.fl6_gre_key = tunnel_id_to_key32(key->tun_id);
987 
988 		dsfield = key->tos;
989 		if (!test_bit(IP_TUNNEL_ERSPAN_OPT_BIT,
990 			      tun_info->key.tun_flags))
991 			goto tx_err;
992 		if (tun_info->options_len < sizeof(*md))
993 			goto tx_err;
994 		md = ip_tunnel_info_opts(tun_info);
995 
996 		tun_id = tunnel_id_to_key32(key->tun_id);
997 		if (md->version == 1) {
998 			erspan_build_header(skb,
999 					    ntohl(tun_id),
1000 					    ntohl(md->u.index), truncate,
1001 					    false);
1002 			proto = htons(ETH_P_ERSPAN);
1003 		} else if (md->version == 2) {
1004 			erspan_build_header_v2(skb,
1005 					       ntohl(tun_id),
1006 					       md->u.md2.dir,
1007 					       get_hwid(&md->u.md2),
1008 					       truncate, false);
1009 			proto = htons(ETH_P_ERSPAN2);
1010 		} else {
1011 			goto tx_err;
1012 		}
1013 	} else {
1014 		switch (skb->protocol) {
1015 		case htons(ETH_P_IP):
1016 			memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
1017 			prepare_ip6gre_xmit_ipv4(skb, dev, &fl6,
1018 						 &dsfield, &encap_limit);
1019 			break;
1020 		case htons(ETH_P_IPV6):
1021 			if (ipv6_addr_equal(&t->parms.raddr, &ipv6_hdr(skb)->saddr))
1022 				goto tx_err;
1023 			if (prepare_ip6gre_xmit_ipv6(skb, dev, &fl6,
1024 						     &dsfield, &encap_limit))
1025 				goto tx_err;
1026 			break;
1027 		default:
1028 			memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6));
1029 			break;
1030 		}
1031 
1032 		if (t->parms.erspan_ver == 1) {
1033 			erspan_build_header(skb, ntohl(t->parms.o_key),
1034 					    t->parms.index,
1035 					    truncate, false);
1036 			proto = htons(ETH_P_ERSPAN);
1037 		} else if (t->parms.erspan_ver == 2) {
1038 			erspan_build_header_v2(skb, ntohl(t->parms.o_key),
1039 					       t->parms.dir,
1040 					       t->parms.hwid,
1041 					       truncate, false);
1042 			proto = htons(ETH_P_ERSPAN2);
1043 		} else {
1044 			goto tx_err;
1045 		}
1046 
1047 		fl6.daddr = t->parms.raddr;
1048 	}
1049 
1050 	/* Push GRE header. */
1051 	__set_bit(IP_TUNNEL_SEQ_BIT, flags);
1052 	gre_build_header(skb, 8, flags, proto, 0,
1053 			 htonl(atomic_fetch_inc(&t->o_seqno)));
1054 
1055 	/* TooBig packet may have updated dst->dev's mtu */
1056 	if (!t->parms.collect_md && dst) {
1057 		mtu = READ_ONCE(dst_dev(dst)->mtu);
1058 		if (dst_mtu(dst) > mtu)
1059 			dst->ops->update_pmtu(dst, NULL, skb, mtu, false);
1060 	}
1061 	err = ip6_tnl_xmit(skb, dev, dsfield, &fl6, encap_limit, &mtu,
1062 			   NEXTHDR_GRE);
1063 	if (err != 0) {
1064 		/* XXX: send ICMP error even if DF is not set. */
1065 		if (err == -EMSGSIZE) {
1066 			if (skb->protocol == htons(ETH_P_IP))
1067 				icmp_ndo_send(skb, ICMP_DEST_UNREACH,
1068 					      ICMP_FRAG_NEEDED, htonl(mtu));
1069 			else
1070 				icmpv6_ndo_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
1071 		}
1072 
1073 		goto tx_err;
1074 	}
1075 	return NETDEV_TX_OK;
1076 
1077 tx_err:
1078 	if (!IS_ERR(tun_info))
1079 		DEV_STATS_INC(dev, tx_errors);
1080 	DEV_STATS_INC(dev, tx_dropped);
1081 	kfree_skb(skb);
1082 	return NETDEV_TX_OK;
1083 }
1084 
1085 static void ip6gre_tnl_link_config_common(struct ip6_tnl *t)
1086 {
1087 	struct net_device *dev = t->dev;
1088 	struct __ip6_tnl_parm *p = &t->parms;
1089 	struct flowi6 *fl6 = &t->fl.u.ip6;
1090 
1091 	if (dev->type != ARPHRD_ETHER) {
1092 		__dev_addr_set(dev, &p->laddr, sizeof(struct in6_addr));
1093 		memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr));
1094 	}
1095 
1096 	/* Set up flowi template */
1097 	fl6->saddr = p->laddr;
1098 	fl6->daddr = p->raddr;
1099 	fl6->flowi6_oif = p->link;
1100 	fl6->flowlabel = 0;
1101 	fl6->flowi6_proto = IPPROTO_GRE;
1102 	fl6->fl6_gre_key = t->parms.o_key;
1103 
1104 	if (!(p->flags&IP6_TNL_F_USE_ORIG_TCLASS))
1105 		fl6->flowlabel |= IPV6_TCLASS_MASK & p->flowinfo;
1106 	if (!(p->flags&IP6_TNL_F_USE_ORIG_FLOWLABEL))
1107 		fl6->flowlabel |= IPV6_FLOWLABEL_MASK & p->flowinfo;
1108 
1109 	p->flags &= ~(IP6_TNL_F_CAP_XMIT|IP6_TNL_F_CAP_RCV|IP6_TNL_F_CAP_PER_PACKET);
1110 	p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr);
1111 
1112 	if (p->flags&IP6_TNL_F_CAP_XMIT &&
1113 			p->flags&IP6_TNL_F_CAP_RCV && dev->type != ARPHRD_ETHER)
1114 		dev->flags |= IFF_POINTOPOINT;
1115 	else
1116 		dev->flags &= ~IFF_POINTOPOINT;
1117 }
1118 
1119 static void ip6gre_tnl_link_config_route(struct ip6_tnl *t, int set_mtu,
1120 					 int t_hlen)
1121 {
1122 	const struct __ip6_tnl_parm *p = &t->parms;
1123 	struct net_device *dev = t->dev;
1124 
1125 	if (p->flags & IP6_TNL_F_CAP_XMIT) {
1126 		int strict = (ipv6_addr_type(&p->raddr) &
1127 			      (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL));
1128 
1129 		struct rt6_info *rt = rt6_lookup(t->net,
1130 						 &p->raddr, &p->laddr,
1131 						 p->link, NULL, strict);
1132 
1133 		if (!rt)
1134 			return;
1135 
1136 		if (rt->dst.dev) {
1137 			unsigned short dst_len = rt->dst.dev->hard_header_len +
1138 						 t_hlen;
1139 
1140 			if (t->dev->header_ops)
1141 				dev->hard_header_len = dst_len;
1142 			else
1143 				dev->needed_headroom = dst_len;
1144 
1145 			if (set_mtu) {
1146 				int mtu = rt->dst.dev->mtu - t_hlen;
1147 
1148 				if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1149 					mtu -= 8;
1150 				if (dev->type == ARPHRD_ETHER)
1151 					mtu -= ETH_HLEN;
1152 
1153 				if (mtu < IPV6_MIN_MTU)
1154 					mtu = IPV6_MIN_MTU;
1155 				WRITE_ONCE(dev->mtu, mtu);
1156 			}
1157 		}
1158 		ip6_rt_put(rt);
1159 	}
1160 }
1161 
1162 static int ip6gre_calc_hlen(struct ip6_tnl *tunnel)
1163 {
1164 	int t_hlen;
1165 
1166 	tunnel->tun_hlen = gre_calc_hlen(tunnel->parms.o_flags);
1167 	tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen;
1168 
1169 	t_hlen = tunnel->hlen + sizeof(struct ipv6hdr);
1170 
1171 	if (tunnel->dev->header_ops)
1172 		tunnel->dev->hard_header_len = LL_MAX_HEADER + t_hlen;
1173 	else
1174 		tunnel->dev->needed_headroom = LL_MAX_HEADER + t_hlen;
1175 
1176 	return t_hlen;
1177 }
1178 
1179 static void ip6gre_tnl_link_config(struct ip6_tnl *t, int set_mtu)
1180 {
1181 	ip6gre_tnl_link_config_common(t);
1182 	ip6gre_tnl_link_config_route(t, set_mtu, ip6gre_calc_hlen(t));
1183 }
1184 
1185 static void ip6gre_tnl_copy_tnl_parm(struct ip6_tnl *t,
1186 				     const struct __ip6_tnl_parm *p)
1187 {
1188 	t->parms.laddr = p->laddr;
1189 	t->parms.raddr = p->raddr;
1190 	t->parms.flags = p->flags;
1191 	t->parms.hop_limit = p->hop_limit;
1192 	t->parms.encap_limit = p->encap_limit;
1193 	t->parms.flowinfo = p->flowinfo;
1194 	t->parms.link = p->link;
1195 	t->parms.proto = p->proto;
1196 	t->parms.i_key = p->i_key;
1197 	t->parms.o_key = p->o_key;
1198 	ip_tunnel_flags_copy(t->parms.i_flags, p->i_flags);
1199 	ip_tunnel_flags_copy(t->parms.o_flags, p->o_flags);
1200 	t->parms.fwmark = p->fwmark;
1201 	t->parms.erspan_ver = p->erspan_ver;
1202 	t->parms.index = p->index;
1203 	t->parms.dir = p->dir;
1204 	t->parms.hwid = p->hwid;
1205 	dst_cache_reset(&t->dst_cache);
1206 }
1207 
1208 static int ip6gre_tnl_change(struct ip6_tnl *t, const struct __ip6_tnl_parm *p,
1209 			     int set_mtu)
1210 {
1211 	ip6gre_tnl_copy_tnl_parm(t, p);
1212 	ip6gre_tnl_link_config(t, set_mtu);
1213 	return 0;
1214 }
1215 
1216 static void ip6gre_tnl_parm_from_user(struct __ip6_tnl_parm *p,
1217 	const struct ip6_tnl_parm2 *u)
1218 {
1219 	p->laddr = u->laddr;
1220 	p->raddr = u->raddr;
1221 	p->flags = u->flags;
1222 	p->hop_limit = u->hop_limit;
1223 	p->encap_limit = u->encap_limit;
1224 	p->flowinfo = u->flowinfo;
1225 	p->link = u->link;
1226 	p->i_key = u->i_key;
1227 	p->o_key = u->o_key;
1228 	gre_flags_to_tnl_flags(p->i_flags, u->i_flags);
1229 	gre_flags_to_tnl_flags(p->o_flags, u->o_flags);
1230 	memcpy(p->name, u->name, sizeof(u->name));
1231 }
1232 
1233 static void ip6gre_tnl_parm_to_user(struct ip6_tnl_parm2 *u,
1234 	const struct __ip6_tnl_parm *p)
1235 {
1236 	u->proto = IPPROTO_GRE;
1237 	u->laddr = p->laddr;
1238 	u->raddr = p->raddr;
1239 	u->flags = p->flags;
1240 	u->hop_limit = p->hop_limit;
1241 	u->encap_limit = p->encap_limit;
1242 	u->flowinfo = p->flowinfo;
1243 	u->link = p->link;
1244 	u->i_key = p->i_key;
1245 	u->o_key = p->o_key;
1246 	u->i_flags = gre_tnl_flags_to_gre_flags(p->i_flags);
1247 	u->o_flags = gre_tnl_flags_to_gre_flags(p->o_flags);
1248 	memcpy(u->name, p->name, sizeof(u->name));
1249 }
1250 
1251 static int ip6gre_tunnel_siocdevprivate(struct net_device *dev,
1252 					struct ifreq *ifr, void __user *data,
1253 					int cmd)
1254 {
1255 	int err = 0;
1256 	struct ip6_tnl_parm2 p;
1257 	struct __ip6_tnl_parm p1;
1258 	struct ip6_tnl *t = netdev_priv(dev);
1259 	struct net *net = t->net;
1260 	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
1261 
1262 	memset(&p1, 0, sizeof(p1));
1263 
1264 	switch (cmd) {
1265 	case SIOCGETTUNNEL:
1266 		if (dev == ign->fb_tunnel_dev) {
1267 			if (copy_from_user(&p, data, sizeof(p))) {
1268 				err = -EFAULT;
1269 				break;
1270 			}
1271 			ip6gre_tnl_parm_from_user(&p1, &p);
1272 			t = ip6gre_tunnel_locate(net, &p1, 0);
1273 			if (!t)
1274 				t = netdev_priv(dev);
1275 		}
1276 		memset(&p, 0, sizeof(p));
1277 		ip6gre_tnl_parm_to_user(&p, &t->parms);
1278 		if (copy_to_user(data, &p, sizeof(p)))
1279 			err = -EFAULT;
1280 		break;
1281 
1282 	case SIOCADDTUNNEL:
1283 	case SIOCCHGTUNNEL:
1284 		err = -EPERM;
1285 		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1286 			goto done;
1287 
1288 		err = -EFAULT;
1289 		if (copy_from_user(&p, data, sizeof(p)))
1290 			goto done;
1291 
1292 		err = -EINVAL;
1293 		if ((p.i_flags|p.o_flags)&(GRE_VERSION|GRE_ROUTING))
1294 			goto done;
1295 
1296 		if (!(p.i_flags&GRE_KEY))
1297 			p.i_key = 0;
1298 		if (!(p.o_flags&GRE_KEY))
1299 			p.o_key = 0;
1300 
1301 		ip6gre_tnl_parm_from_user(&p1, &p);
1302 		t = ip6gre_tunnel_locate(net, &p1, cmd == SIOCADDTUNNEL);
1303 
1304 		if (dev != ign->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) {
1305 			if (t) {
1306 				if (t->dev != dev) {
1307 					err = -EEXIST;
1308 					break;
1309 				}
1310 			} else {
1311 				t = netdev_priv(dev);
1312 
1313 				ip6gre_tunnel_unlink(ign, t);
1314 				synchronize_net();
1315 				ip6gre_tnl_change(t, &p1, 1);
1316 				ip6gre_tunnel_link(ign, t);
1317 				netdev_state_change(dev);
1318 			}
1319 		}
1320 
1321 		if (t) {
1322 			err = 0;
1323 
1324 			memset(&p, 0, sizeof(p));
1325 			ip6gre_tnl_parm_to_user(&p, &t->parms);
1326 			if (copy_to_user(data, &p, sizeof(p)))
1327 				err = -EFAULT;
1328 		} else
1329 			err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
1330 		break;
1331 
1332 	case SIOCDELTUNNEL:
1333 		err = -EPERM;
1334 		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1335 			goto done;
1336 
1337 		if (dev == ign->fb_tunnel_dev) {
1338 			err = -EFAULT;
1339 			if (copy_from_user(&p, data, sizeof(p)))
1340 				goto done;
1341 			err = -ENOENT;
1342 			ip6gre_tnl_parm_from_user(&p1, &p);
1343 			t = ip6gre_tunnel_locate(net, &p1, 0);
1344 			if (!t)
1345 				goto done;
1346 			err = -EPERM;
1347 			if (t == netdev_priv(ign->fb_tunnel_dev))
1348 				goto done;
1349 			dev = t->dev;
1350 		}
1351 		unregister_netdevice(dev);
1352 		err = 0;
1353 		break;
1354 
1355 	default:
1356 		err = -EINVAL;
1357 	}
1358 
1359 done:
1360 	return err;
1361 }
1362 
1363 static int ip6gre_header(struct sk_buff *skb, struct net_device *dev,
1364 			 unsigned short type, const void *daddr,
1365 			 const void *saddr, unsigned int len)
1366 {
1367 	struct ip6_tnl *t = netdev_priv(dev);
1368 	struct ipv6hdr *ipv6h;
1369 	__be16 *p;
1370 
1371 	ipv6h = skb_push(skb, t->hlen + sizeof(*ipv6h));
1372 	ip6_flow_hdr(ipv6h, 0, ip6_make_flowlabel(dev_net(dev), skb,
1373 						  t->fl.u.ip6.flowlabel,
1374 						  true, &t->fl.u.ip6));
1375 	ipv6h->hop_limit = t->parms.hop_limit;
1376 	ipv6h->nexthdr = NEXTHDR_GRE;
1377 	ipv6h->saddr = t->parms.laddr;
1378 	ipv6h->daddr = t->parms.raddr;
1379 
1380 	p = (__be16 *)(ipv6h + 1);
1381 	p[0] = ip_tunnel_flags_to_be16(t->parms.o_flags);
1382 	p[1] = htons(type);
1383 
1384 	/*
1385 	 *	Set the source hardware address.
1386 	 */
1387 
1388 	if (saddr)
1389 		memcpy(&ipv6h->saddr, saddr, sizeof(struct in6_addr));
1390 	if (daddr)
1391 		memcpy(&ipv6h->daddr, daddr, sizeof(struct in6_addr));
1392 	if (!ipv6_addr_any(&ipv6h->daddr))
1393 		return t->hlen;
1394 
1395 	return -t->hlen;
1396 }
1397 
1398 static const struct header_ops ip6gre_header_ops = {
1399 	.create	= ip6gre_header,
1400 };
1401 
1402 static const struct net_device_ops ip6gre_netdev_ops = {
1403 	.ndo_init		= ip6gre_tunnel_init,
1404 	.ndo_uninit		= ip6gre_tunnel_uninit,
1405 	.ndo_start_xmit		= ip6gre_tunnel_xmit,
1406 	.ndo_siocdevprivate	= ip6gre_tunnel_siocdevprivate,
1407 	.ndo_change_mtu		= ip6_tnl_change_mtu,
1408 	.ndo_get_iflink		= ip6_tnl_get_iflink,
1409 };
1410 
1411 static void ip6gre_dev_free(struct net_device *dev)
1412 {
1413 	struct ip6_tnl *t = netdev_priv(dev);
1414 
1415 	gro_cells_destroy(&t->gro_cells);
1416 	dst_cache_destroy(&t->dst_cache);
1417 }
1418 
1419 static void ip6gre_tunnel_setup(struct net_device *dev)
1420 {
1421 	dev->netdev_ops = &ip6gre_netdev_ops;
1422 	dev->needs_free_netdev = true;
1423 	dev->priv_destructor = ip6gre_dev_free;
1424 
1425 	dev->pcpu_stat_type = NETDEV_PCPU_STAT_TSTATS;
1426 	dev->type = ARPHRD_IP6GRE;
1427 
1428 	dev->flags |= IFF_NOARP;
1429 	dev->addr_len = sizeof(struct in6_addr);
1430 	netif_keep_dst(dev);
1431 	/* This perm addr will be used as interface identifier by IPv6 */
1432 	dev->addr_assign_type = NET_ADDR_RANDOM;
1433 	eth_random_addr(dev->perm_addr);
1434 }
1435 
1436 #define GRE6_FEATURES (NETIF_F_SG |		\
1437 		       NETIF_F_FRAGLIST |	\
1438 		       NETIF_F_HIGHDMA |	\
1439 		       NETIF_F_HW_CSUM)
1440 
1441 static void ip6gre_tnl_init_features(struct net_device *dev)
1442 {
1443 	struct ip6_tnl *nt = netdev_priv(dev);
1444 
1445 	dev->features		|= GRE6_FEATURES;
1446 	dev->hw_features	|= GRE6_FEATURES;
1447 
1448 	/* TCP offload with GRE SEQ is not supported, nor can we support 2
1449 	 * levels of outer headers requiring an update.
1450 	 */
1451 	if (test_bit(IP_TUNNEL_SEQ_BIT, nt->parms.o_flags))
1452 		return;
1453 	if (test_bit(IP_TUNNEL_CSUM_BIT, nt->parms.o_flags) &&
1454 	    nt->encap.type != TUNNEL_ENCAP_NONE)
1455 		return;
1456 
1457 	dev->features |= NETIF_F_GSO_SOFTWARE;
1458 	dev->hw_features |= NETIF_F_GSO_SOFTWARE;
1459 
1460 	dev->lltx = true;
1461 }
1462 
1463 static int ip6gre_tunnel_init_common(struct net_device *dev)
1464 {
1465 	struct ip6_tnl *tunnel;
1466 	int ret;
1467 	int t_hlen;
1468 
1469 	tunnel = netdev_priv(dev);
1470 
1471 	tunnel->dev = dev;
1472 	strcpy(tunnel->parms.name, dev->name);
1473 
1474 	ret = dst_cache_init(&tunnel->dst_cache, GFP_KERNEL);
1475 	if (ret)
1476 		return ret;
1477 
1478 	ret = gro_cells_init(&tunnel->gro_cells, dev);
1479 	if (ret)
1480 		goto cleanup_dst_cache_init;
1481 
1482 	t_hlen = ip6gre_calc_hlen(tunnel);
1483 	dev->mtu = ETH_DATA_LEN - t_hlen;
1484 	if (dev->type == ARPHRD_ETHER)
1485 		dev->mtu -= ETH_HLEN;
1486 	if (!(tunnel->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1487 		dev->mtu -= 8;
1488 
1489 	if (tunnel->parms.collect_md) {
1490 		netif_keep_dst(dev);
1491 	}
1492 	ip6gre_tnl_init_features(dev);
1493 
1494 	netdev_hold(dev, &tunnel->dev_tracker, GFP_KERNEL);
1495 	netdev_lockdep_set_classes(dev);
1496 	return 0;
1497 
1498 cleanup_dst_cache_init:
1499 	dst_cache_destroy(&tunnel->dst_cache);
1500 	return ret;
1501 }
1502 
1503 static int ip6gre_tunnel_init(struct net_device *dev)
1504 {
1505 	struct ip6_tnl *tunnel;
1506 	int ret;
1507 
1508 	ret = ip6gre_tunnel_init_common(dev);
1509 	if (ret)
1510 		return ret;
1511 
1512 	tunnel = netdev_priv(dev);
1513 
1514 	if (tunnel->parms.collect_md)
1515 		return 0;
1516 
1517 	__dev_addr_set(dev, &tunnel->parms.laddr, sizeof(struct in6_addr));
1518 	memcpy(dev->broadcast, &tunnel->parms.raddr, sizeof(struct in6_addr));
1519 
1520 	if (ipv6_addr_any(&tunnel->parms.raddr))
1521 		dev->header_ops = &ip6gre_header_ops;
1522 
1523 	return 0;
1524 }
1525 
1526 static void ip6gre_fb_tunnel_init(struct net_device *dev)
1527 {
1528 	struct ip6_tnl *tunnel = netdev_priv(dev);
1529 
1530 	tunnel->dev = dev;
1531 	tunnel->net = dev_net(dev);
1532 	strcpy(tunnel->parms.name, dev->name);
1533 
1534 	tunnel->hlen		= sizeof(struct ipv6hdr) + 4;
1535 }
1536 
1537 static struct inet6_protocol ip6gre_protocol __read_mostly = {
1538 	.handler     = gre_rcv,
1539 	.err_handler = ip6gre_err,
1540 	.flags       = INET6_PROTO_FINAL,
1541 };
1542 
1543 static void __net_exit ip6gre_exit_rtnl_net(struct net *net, struct list_head *head)
1544 {
1545 	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
1546 	struct net_device *dev, *aux;
1547 	int prio;
1548 
1549 	for_each_netdev_safe(net, dev, aux)
1550 		if (dev->rtnl_link_ops == &ip6gre_link_ops ||
1551 		    dev->rtnl_link_ops == &ip6gre_tap_ops ||
1552 		    dev->rtnl_link_ops == &ip6erspan_tap_ops)
1553 			unregister_netdevice_queue(dev, head);
1554 
1555 	for (prio = 0; prio < 4; prio++) {
1556 		int h;
1557 		for (h = 0; h < IP6_GRE_HASH_SIZE; h++) {
1558 			struct ip6_tnl *t;
1559 
1560 			t = rtnl_net_dereference(net, ign->tunnels[prio][h]);
1561 
1562 			while (t) {
1563 				/* If dev is in the same netns, it has already
1564 				 * been added to the list by the previous loop.
1565 				 */
1566 				if (!net_eq(dev_net(t->dev), net))
1567 					unregister_netdevice_queue(t->dev, head);
1568 
1569 				t = rtnl_net_dereference(net, t->next);
1570 			}
1571 		}
1572 	}
1573 }
1574 
1575 static int __net_init ip6gre_init_net(struct net *net)
1576 {
1577 	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
1578 	struct net_device *ndev;
1579 	int err;
1580 
1581 	if (!net_has_fallback_tunnels(net))
1582 		return 0;
1583 	ndev = alloc_netdev(sizeof(struct ip6_tnl), "ip6gre0",
1584 			    NET_NAME_UNKNOWN, ip6gre_tunnel_setup);
1585 	if (!ndev) {
1586 		err = -ENOMEM;
1587 		goto err_alloc_dev;
1588 	}
1589 	ign->fb_tunnel_dev = ndev;
1590 	dev_net_set(ign->fb_tunnel_dev, net);
1591 	/* FB netdevice is special: we have one, and only one per netns.
1592 	 * Allowing to move it to another netns is clearly unsafe.
1593 	 */
1594 	ign->fb_tunnel_dev->netns_immutable = true;
1595 
1596 	ip6gre_fb_tunnel_init(ign->fb_tunnel_dev);
1597 	ign->fb_tunnel_dev->rtnl_link_ops = &ip6gre_link_ops;
1598 
1599 	err = register_netdev(ign->fb_tunnel_dev);
1600 	if (err)
1601 		goto err_reg_dev;
1602 
1603 	rcu_assign_pointer(ign->tunnels_wc[0],
1604 			   netdev_priv(ign->fb_tunnel_dev));
1605 	return 0;
1606 
1607 err_reg_dev:
1608 	free_netdev(ndev);
1609 err_alloc_dev:
1610 	return err;
1611 }
1612 
1613 static struct pernet_operations ip6gre_net_ops = {
1614 	.init = ip6gre_init_net,
1615 	.exit_rtnl = ip6gre_exit_rtnl_net,
1616 	.id   = &ip6gre_net_id,
1617 	.size = sizeof(struct ip6gre_net),
1618 };
1619 
1620 static int ip6gre_tunnel_validate(struct nlattr *tb[], struct nlattr *data[],
1621 				  struct netlink_ext_ack *extack)
1622 {
1623 	__be16 flags;
1624 
1625 	if (!data)
1626 		return 0;
1627 
1628 	flags = 0;
1629 	if (data[IFLA_GRE_IFLAGS])
1630 		flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]);
1631 	if (data[IFLA_GRE_OFLAGS])
1632 		flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]);
1633 	if (flags & (GRE_VERSION|GRE_ROUTING))
1634 		return -EINVAL;
1635 
1636 	return 0;
1637 }
1638 
1639 static int ip6gre_tap_validate(struct nlattr *tb[], struct nlattr *data[],
1640 			       struct netlink_ext_ack *extack)
1641 {
1642 	struct in6_addr daddr;
1643 
1644 	if (tb[IFLA_ADDRESS]) {
1645 		if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
1646 			return -EINVAL;
1647 		if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
1648 			return -EADDRNOTAVAIL;
1649 	}
1650 
1651 	if (!data)
1652 		goto out;
1653 
1654 	if (data[IFLA_GRE_REMOTE]) {
1655 		daddr = nla_get_in6_addr(data[IFLA_GRE_REMOTE]);
1656 		if (ipv6_addr_any(&daddr))
1657 			return -EINVAL;
1658 	}
1659 
1660 out:
1661 	return ip6gre_tunnel_validate(tb, data, extack);
1662 }
1663 
1664 static int ip6erspan_tap_validate(struct nlattr *tb[], struct nlattr *data[],
1665 				  struct netlink_ext_ack *extack)
1666 {
1667 	__be16 flags = 0;
1668 	int ret, ver = 0;
1669 
1670 	if (!data)
1671 		return 0;
1672 
1673 	ret = ip6gre_tap_validate(tb, data, extack);
1674 	if (ret)
1675 		return ret;
1676 
1677 	/* ERSPAN should only have GRE sequence and key flag */
1678 	if (data[IFLA_GRE_OFLAGS])
1679 		flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]);
1680 	if (data[IFLA_GRE_IFLAGS])
1681 		flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]);
1682 	if (!data[IFLA_GRE_COLLECT_METADATA] &&
1683 	    flags != (GRE_SEQ | GRE_KEY))
1684 		return -EINVAL;
1685 
1686 	/* ERSPAN Session ID only has 10-bit. Since we reuse
1687 	 * 32-bit key field as ID, check it's range.
1688 	 */
1689 	if (data[IFLA_GRE_IKEY] &&
1690 	    (ntohl(nla_get_be32(data[IFLA_GRE_IKEY])) & ~ID_MASK))
1691 		return -EINVAL;
1692 
1693 	if (data[IFLA_GRE_OKEY] &&
1694 	    (ntohl(nla_get_be32(data[IFLA_GRE_OKEY])) & ~ID_MASK))
1695 		return -EINVAL;
1696 
1697 	if (data[IFLA_GRE_ERSPAN_VER]) {
1698 		ver = nla_get_u8(data[IFLA_GRE_ERSPAN_VER]);
1699 		if (ver != 1 && ver != 2)
1700 			return -EINVAL;
1701 	}
1702 
1703 	if (ver == 1) {
1704 		if (data[IFLA_GRE_ERSPAN_INDEX]) {
1705 			u32 index = nla_get_u32(data[IFLA_GRE_ERSPAN_INDEX]);
1706 
1707 			if (index & ~INDEX_MASK)
1708 				return -EINVAL;
1709 		}
1710 	} else if (ver == 2) {
1711 		if (data[IFLA_GRE_ERSPAN_DIR]) {
1712 			u16 dir = nla_get_u8(data[IFLA_GRE_ERSPAN_DIR]);
1713 
1714 			if (dir & ~(DIR_MASK >> DIR_OFFSET))
1715 				return -EINVAL;
1716 		}
1717 
1718 		if (data[IFLA_GRE_ERSPAN_HWID]) {
1719 			u16 hwid = nla_get_u16(data[IFLA_GRE_ERSPAN_HWID]);
1720 
1721 			if (hwid & ~(HWID_MASK >> HWID_OFFSET))
1722 				return -EINVAL;
1723 		}
1724 	}
1725 
1726 	return 0;
1727 }
1728 
1729 static void ip6erspan_set_version(struct nlattr *data[],
1730 				  struct __ip6_tnl_parm *parms)
1731 {
1732 	if (!data)
1733 		return;
1734 
1735 	parms->erspan_ver = 1;
1736 	if (data[IFLA_GRE_ERSPAN_VER])
1737 		parms->erspan_ver = nla_get_u8(data[IFLA_GRE_ERSPAN_VER]);
1738 
1739 	if (parms->erspan_ver == 1) {
1740 		if (data[IFLA_GRE_ERSPAN_INDEX])
1741 			parms->index = nla_get_u32(data[IFLA_GRE_ERSPAN_INDEX]);
1742 	} else if (parms->erspan_ver == 2) {
1743 		if (data[IFLA_GRE_ERSPAN_DIR])
1744 			parms->dir = nla_get_u8(data[IFLA_GRE_ERSPAN_DIR]);
1745 		if (data[IFLA_GRE_ERSPAN_HWID])
1746 			parms->hwid = nla_get_u16(data[IFLA_GRE_ERSPAN_HWID]);
1747 	}
1748 }
1749 
1750 static void ip6gre_netlink_parms(struct nlattr *data[],
1751 				struct __ip6_tnl_parm *parms)
1752 {
1753 	memset(parms, 0, sizeof(*parms));
1754 
1755 	if (!data)
1756 		return;
1757 
1758 	if (data[IFLA_GRE_LINK])
1759 		parms->link = nla_get_u32(data[IFLA_GRE_LINK]);
1760 
1761 	if (data[IFLA_GRE_IFLAGS])
1762 		gre_flags_to_tnl_flags(parms->i_flags,
1763 				       nla_get_be16(data[IFLA_GRE_IFLAGS]));
1764 
1765 	if (data[IFLA_GRE_OFLAGS])
1766 		gre_flags_to_tnl_flags(parms->o_flags,
1767 				       nla_get_be16(data[IFLA_GRE_OFLAGS]));
1768 
1769 	if (data[IFLA_GRE_IKEY])
1770 		parms->i_key = nla_get_be32(data[IFLA_GRE_IKEY]);
1771 
1772 	if (data[IFLA_GRE_OKEY])
1773 		parms->o_key = nla_get_be32(data[IFLA_GRE_OKEY]);
1774 
1775 	if (data[IFLA_GRE_LOCAL])
1776 		parms->laddr = nla_get_in6_addr(data[IFLA_GRE_LOCAL]);
1777 
1778 	if (data[IFLA_GRE_REMOTE])
1779 		parms->raddr = nla_get_in6_addr(data[IFLA_GRE_REMOTE]);
1780 
1781 	if (data[IFLA_GRE_TTL])
1782 		parms->hop_limit = nla_get_u8(data[IFLA_GRE_TTL]);
1783 
1784 	if (data[IFLA_GRE_ENCAP_LIMIT])
1785 		parms->encap_limit = nla_get_u8(data[IFLA_GRE_ENCAP_LIMIT]);
1786 
1787 	if (data[IFLA_GRE_FLOWINFO])
1788 		parms->flowinfo = nla_get_be32(data[IFLA_GRE_FLOWINFO]);
1789 
1790 	if (data[IFLA_GRE_FLAGS])
1791 		parms->flags = nla_get_u32(data[IFLA_GRE_FLAGS]);
1792 
1793 	if (data[IFLA_GRE_FWMARK])
1794 		parms->fwmark = nla_get_u32(data[IFLA_GRE_FWMARK]);
1795 
1796 	if (data[IFLA_GRE_COLLECT_METADATA])
1797 		parms->collect_md = true;
1798 }
1799 
1800 static int ip6gre_tap_init(struct net_device *dev)
1801 {
1802 	int ret;
1803 
1804 	ret = ip6gre_tunnel_init_common(dev);
1805 	if (ret)
1806 		return ret;
1807 
1808 	dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1809 
1810 	return 0;
1811 }
1812 
1813 static const struct net_device_ops ip6gre_tap_netdev_ops = {
1814 	.ndo_init = ip6gre_tap_init,
1815 	.ndo_uninit = ip6gre_tunnel_uninit,
1816 	.ndo_start_xmit = ip6gre_tunnel_xmit,
1817 	.ndo_set_mac_address = eth_mac_addr,
1818 	.ndo_validate_addr = eth_validate_addr,
1819 	.ndo_change_mtu = ip6_tnl_change_mtu,
1820 	.ndo_get_iflink = ip6_tnl_get_iflink,
1821 };
1822 
1823 static int ip6erspan_calc_hlen(struct ip6_tnl *tunnel)
1824 {
1825 	int t_hlen;
1826 
1827 	tunnel->tun_hlen = 8;
1828 	tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen +
1829 		       erspan_hdr_len(tunnel->parms.erspan_ver);
1830 
1831 	t_hlen = tunnel->hlen + sizeof(struct ipv6hdr);
1832 	tunnel->dev->needed_headroom = LL_MAX_HEADER + t_hlen;
1833 	return t_hlen;
1834 }
1835 
1836 static int ip6erspan_tap_init(struct net_device *dev)
1837 {
1838 	struct ip6_tnl *tunnel;
1839 	int t_hlen;
1840 	int ret;
1841 
1842 	tunnel = netdev_priv(dev);
1843 
1844 	tunnel->dev = dev;
1845 	strcpy(tunnel->parms.name, dev->name);
1846 
1847 	ret = dst_cache_init(&tunnel->dst_cache, GFP_KERNEL);
1848 	if (ret)
1849 		return ret;
1850 
1851 	ret = gro_cells_init(&tunnel->gro_cells, dev);
1852 	if (ret)
1853 		goto cleanup_dst_cache_init;
1854 
1855 	t_hlen = ip6erspan_calc_hlen(tunnel);
1856 	dev->mtu = ETH_DATA_LEN - t_hlen;
1857 	if (dev->type == ARPHRD_ETHER)
1858 		dev->mtu -= ETH_HLEN;
1859 	if (!(tunnel->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1860 		dev->mtu -= 8;
1861 
1862 	dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1863 	ip6erspan_tnl_link_config(tunnel, 1);
1864 
1865 	netdev_hold(dev, &tunnel->dev_tracker, GFP_KERNEL);
1866 	netdev_lockdep_set_classes(dev);
1867 	return 0;
1868 
1869 cleanup_dst_cache_init:
1870 	dst_cache_destroy(&tunnel->dst_cache);
1871 	return ret;
1872 }
1873 
1874 static const struct net_device_ops ip6erspan_netdev_ops = {
1875 	.ndo_init =		ip6erspan_tap_init,
1876 	.ndo_uninit =		ip6erspan_tunnel_uninit,
1877 	.ndo_start_xmit =	ip6erspan_tunnel_xmit,
1878 	.ndo_set_mac_address =	eth_mac_addr,
1879 	.ndo_validate_addr =	eth_validate_addr,
1880 	.ndo_change_mtu =	ip6_tnl_change_mtu,
1881 	.ndo_get_iflink =	ip6_tnl_get_iflink,
1882 };
1883 
1884 static void ip6gre_tap_setup(struct net_device *dev)
1885 {
1886 
1887 	ether_setup(dev);
1888 
1889 	dev->max_mtu = 0;
1890 	dev->netdev_ops = &ip6gre_tap_netdev_ops;
1891 	dev->needs_free_netdev = true;
1892 	dev->priv_destructor = ip6gre_dev_free;
1893 
1894 	dev->pcpu_stat_type = NETDEV_PCPU_STAT_TSTATS;
1895 	dev->priv_flags &= ~IFF_TX_SKB_SHARING;
1896 	dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1897 	netif_keep_dst(dev);
1898 }
1899 
1900 static bool ip6gre_netlink_encap_parms(struct nlattr *data[],
1901 				       struct ip_tunnel_encap *ipencap)
1902 {
1903 	bool ret = false;
1904 
1905 	memset(ipencap, 0, sizeof(*ipencap));
1906 
1907 	if (!data)
1908 		return ret;
1909 
1910 	if (data[IFLA_GRE_ENCAP_TYPE]) {
1911 		ret = true;
1912 		ipencap->type = nla_get_u16(data[IFLA_GRE_ENCAP_TYPE]);
1913 	}
1914 
1915 	if (data[IFLA_GRE_ENCAP_FLAGS]) {
1916 		ret = true;
1917 		ipencap->flags = nla_get_u16(data[IFLA_GRE_ENCAP_FLAGS]);
1918 	}
1919 
1920 	if (data[IFLA_GRE_ENCAP_SPORT]) {
1921 		ret = true;
1922 		ipencap->sport = nla_get_be16(data[IFLA_GRE_ENCAP_SPORT]);
1923 	}
1924 
1925 	if (data[IFLA_GRE_ENCAP_DPORT]) {
1926 		ret = true;
1927 		ipencap->dport = nla_get_be16(data[IFLA_GRE_ENCAP_DPORT]);
1928 	}
1929 
1930 	return ret;
1931 }
1932 
1933 static int ip6gre_newlink_common(struct net *link_net, struct net_device *dev,
1934 				 struct nlattr *tb[], struct nlattr *data[],
1935 				 struct netlink_ext_ack *extack)
1936 {
1937 	struct ip6_tnl *nt;
1938 	struct ip_tunnel_encap ipencap;
1939 	int err;
1940 
1941 	nt = netdev_priv(dev);
1942 
1943 	if (ip6gre_netlink_encap_parms(data, &ipencap)) {
1944 		int err = ip6_tnl_encap_setup(nt, &ipencap);
1945 
1946 		if (err < 0)
1947 			return err;
1948 	}
1949 
1950 	if (dev->type == ARPHRD_ETHER && !tb[IFLA_ADDRESS])
1951 		eth_hw_addr_random(dev);
1952 
1953 	nt->dev = dev;
1954 	nt->net = link_net;
1955 
1956 	err = register_netdevice(dev);
1957 	if (err)
1958 		goto out;
1959 
1960 	if (tb[IFLA_MTU])
1961 		ip6_tnl_change_mtu(dev, nla_get_u32(tb[IFLA_MTU]));
1962 
1963 out:
1964 	return err;
1965 }
1966 
1967 static int ip6gre_newlink(struct net_device *dev,
1968 			  struct rtnl_newlink_params *params,
1969 			  struct netlink_ext_ack *extack)
1970 {
1971 	struct net *net = params->link_net ? : dev_net(dev);
1972 	struct ip6_tnl *nt = netdev_priv(dev);
1973 	struct nlattr **data = params->data;
1974 	struct nlattr **tb = params->tb;
1975 	struct ip6gre_net *ign;
1976 	int err;
1977 
1978 	ip6gre_netlink_parms(data, &nt->parms);
1979 	ign = net_generic(net, ip6gre_net_id);
1980 
1981 	if (nt->parms.collect_md) {
1982 		if (rtnl_dereference(ign->collect_md_tun))
1983 			return -EEXIST;
1984 	} else {
1985 		if (ip6gre_tunnel_find(net, &nt->parms, dev->type))
1986 			return -EEXIST;
1987 	}
1988 
1989 	err = ip6gre_newlink_common(net, dev, tb, data, extack);
1990 	if (!err) {
1991 		ip6gre_tnl_link_config(nt, !tb[IFLA_MTU]);
1992 		ip6gre_tunnel_link_md(ign, nt);
1993 		ip6gre_tunnel_link(net_generic(net, ip6gre_net_id), nt);
1994 	}
1995 	return err;
1996 }
1997 
1998 static struct ip6_tnl *
1999 ip6gre_changelink_common(struct net_device *dev, struct nlattr *tb[],
2000 			 struct nlattr *data[], struct __ip6_tnl_parm *p_p,
2001 			 struct netlink_ext_ack *extack)
2002 {
2003 	struct ip6_tnl *t, *nt = netdev_priv(dev);
2004 	struct net *net = nt->net;
2005 	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
2006 	struct ip_tunnel_encap ipencap;
2007 
2008 	if (dev == ign->fb_tunnel_dev)
2009 		return ERR_PTR(-EINVAL);
2010 
2011 	if (ip6gre_netlink_encap_parms(data, &ipencap)) {
2012 		int err = ip6_tnl_encap_setup(nt, &ipencap);
2013 
2014 		if (err < 0)
2015 			return ERR_PTR(err);
2016 	}
2017 
2018 	ip6gre_netlink_parms(data, p_p);
2019 
2020 	t = ip6gre_tunnel_locate(net, p_p, 0);
2021 
2022 	if (t) {
2023 		if (t->dev != dev)
2024 			return ERR_PTR(-EEXIST);
2025 	} else {
2026 		t = nt;
2027 	}
2028 
2029 	return t;
2030 }
2031 
2032 static int ip6gre_changelink(struct net_device *dev, struct nlattr *tb[],
2033 			     struct nlattr *data[],
2034 			     struct netlink_ext_ack *extack)
2035 {
2036 	struct ip6_tnl *t = netdev_priv(dev);
2037 	struct ip6gre_net *ign = net_generic(t->net, ip6gre_net_id);
2038 	struct __ip6_tnl_parm p;
2039 
2040 	t = ip6gre_changelink_common(dev, tb, data, &p, extack);
2041 	if (IS_ERR(t))
2042 		return PTR_ERR(t);
2043 
2044 	ip6gre_tunnel_unlink_md(ign, t);
2045 	ip6gre_tunnel_unlink(ign, t);
2046 	ip6gre_tnl_change(t, &p, !tb[IFLA_MTU]);
2047 	ip6gre_tunnel_link_md(ign, t);
2048 	ip6gre_tunnel_link(ign, t);
2049 	return 0;
2050 }
2051 
2052 static void ip6gre_dellink(struct net_device *dev, struct list_head *head)
2053 {
2054 	struct net *net = dev_net(dev);
2055 	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
2056 
2057 	if (dev != ign->fb_tunnel_dev)
2058 		unregister_netdevice_queue(dev, head);
2059 }
2060 
2061 static size_t ip6gre_get_size(const struct net_device *dev)
2062 {
2063 	return
2064 		/* IFLA_GRE_LINK */
2065 		nla_total_size(4) +
2066 		/* IFLA_GRE_IFLAGS */
2067 		nla_total_size(2) +
2068 		/* IFLA_GRE_OFLAGS */
2069 		nla_total_size(2) +
2070 		/* IFLA_GRE_IKEY */
2071 		nla_total_size(4) +
2072 		/* IFLA_GRE_OKEY */
2073 		nla_total_size(4) +
2074 		/* IFLA_GRE_LOCAL */
2075 		nla_total_size(sizeof(struct in6_addr)) +
2076 		/* IFLA_GRE_REMOTE */
2077 		nla_total_size(sizeof(struct in6_addr)) +
2078 		/* IFLA_GRE_TTL */
2079 		nla_total_size(1) +
2080 		/* IFLA_GRE_ENCAP_LIMIT */
2081 		nla_total_size(1) +
2082 		/* IFLA_GRE_FLOWINFO */
2083 		nla_total_size(4) +
2084 		/* IFLA_GRE_FLAGS */
2085 		nla_total_size(4) +
2086 		/* IFLA_GRE_ENCAP_TYPE */
2087 		nla_total_size(2) +
2088 		/* IFLA_GRE_ENCAP_FLAGS */
2089 		nla_total_size(2) +
2090 		/* IFLA_GRE_ENCAP_SPORT */
2091 		nla_total_size(2) +
2092 		/* IFLA_GRE_ENCAP_DPORT */
2093 		nla_total_size(2) +
2094 		/* IFLA_GRE_COLLECT_METADATA */
2095 		nla_total_size(0) +
2096 		/* IFLA_GRE_FWMARK */
2097 		nla_total_size(4) +
2098 		/* IFLA_GRE_ERSPAN_INDEX */
2099 		nla_total_size(4) +
2100 		0;
2101 }
2102 
2103 static int ip6gre_fill_info(struct sk_buff *skb, const struct net_device *dev)
2104 {
2105 	struct ip6_tnl *t = netdev_priv(dev);
2106 	struct __ip6_tnl_parm *p = &t->parms;
2107 	IP_TUNNEL_DECLARE_FLAGS(o_flags);
2108 
2109 	ip_tunnel_flags_copy(o_flags, p->o_flags);
2110 
2111 	if (p->erspan_ver == 1 || p->erspan_ver == 2) {
2112 		if (!p->collect_md)
2113 			__set_bit(IP_TUNNEL_KEY_BIT, o_flags);
2114 
2115 		if (nla_put_u8(skb, IFLA_GRE_ERSPAN_VER, p->erspan_ver))
2116 			goto nla_put_failure;
2117 
2118 		if (p->erspan_ver == 1) {
2119 			if (nla_put_u32(skb, IFLA_GRE_ERSPAN_INDEX, p->index))
2120 				goto nla_put_failure;
2121 		} else {
2122 			if (nla_put_u8(skb, IFLA_GRE_ERSPAN_DIR, p->dir))
2123 				goto nla_put_failure;
2124 			if (nla_put_u16(skb, IFLA_GRE_ERSPAN_HWID, p->hwid))
2125 				goto nla_put_failure;
2126 		}
2127 	}
2128 
2129 	if (nla_put_u32(skb, IFLA_GRE_LINK, p->link) ||
2130 	    nla_put_be16(skb, IFLA_GRE_IFLAGS,
2131 			 gre_tnl_flags_to_gre_flags(p->i_flags)) ||
2132 	    nla_put_be16(skb, IFLA_GRE_OFLAGS,
2133 			 gre_tnl_flags_to_gre_flags(o_flags)) ||
2134 	    nla_put_be32(skb, IFLA_GRE_IKEY, p->i_key) ||
2135 	    nla_put_be32(skb, IFLA_GRE_OKEY, p->o_key) ||
2136 	    nla_put_in6_addr(skb, IFLA_GRE_LOCAL, &p->laddr) ||
2137 	    nla_put_in6_addr(skb, IFLA_GRE_REMOTE, &p->raddr) ||
2138 	    nla_put_u8(skb, IFLA_GRE_TTL, p->hop_limit) ||
2139 	    nla_put_u8(skb, IFLA_GRE_ENCAP_LIMIT, p->encap_limit) ||
2140 	    nla_put_be32(skb, IFLA_GRE_FLOWINFO, p->flowinfo) ||
2141 	    nla_put_u32(skb, IFLA_GRE_FLAGS, p->flags) ||
2142 	    nla_put_u32(skb, IFLA_GRE_FWMARK, p->fwmark))
2143 		goto nla_put_failure;
2144 
2145 	if (nla_put_u16(skb, IFLA_GRE_ENCAP_TYPE,
2146 			t->encap.type) ||
2147 	    nla_put_be16(skb, IFLA_GRE_ENCAP_SPORT,
2148 			 t->encap.sport) ||
2149 	    nla_put_be16(skb, IFLA_GRE_ENCAP_DPORT,
2150 			 t->encap.dport) ||
2151 	    nla_put_u16(skb, IFLA_GRE_ENCAP_FLAGS,
2152 			t->encap.flags))
2153 		goto nla_put_failure;
2154 
2155 	if (p->collect_md) {
2156 		if (nla_put_flag(skb, IFLA_GRE_COLLECT_METADATA))
2157 			goto nla_put_failure;
2158 	}
2159 
2160 	return 0;
2161 
2162 nla_put_failure:
2163 	return -EMSGSIZE;
2164 }
2165 
2166 static const struct nla_policy ip6gre_policy[IFLA_GRE_MAX + 1] = {
2167 	[IFLA_GRE_LINK]        = { .type = NLA_U32 },
2168 	[IFLA_GRE_IFLAGS]      = { .type = NLA_U16 },
2169 	[IFLA_GRE_OFLAGS]      = { .type = NLA_U16 },
2170 	[IFLA_GRE_IKEY]        = { .type = NLA_U32 },
2171 	[IFLA_GRE_OKEY]        = { .type = NLA_U32 },
2172 	[IFLA_GRE_LOCAL]       = { .len = sizeof_field(struct ipv6hdr, saddr) },
2173 	[IFLA_GRE_REMOTE]      = { .len = sizeof_field(struct ipv6hdr, daddr) },
2174 	[IFLA_GRE_TTL]         = { .type = NLA_U8 },
2175 	[IFLA_GRE_ENCAP_LIMIT] = { .type = NLA_U8 },
2176 	[IFLA_GRE_FLOWINFO]    = { .type = NLA_U32 },
2177 	[IFLA_GRE_FLAGS]       = { .type = NLA_U32 },
2178 	[IFLA_GRE_ENCAP_TYPE]   = { .type = NLA_U16 },
2179 	[IFLA_GRE_ENCAP_FLAGS]  = { .type = NLA_U16 },
2180 	[IFLA_GRE_ENCAP_SPORT]  = { .type = NLA_U16 },
2181 	[IFLA_GRE_ENCAP_DPORT]  = { .type = NLA_U16 },
2182 	[IFLA_GRE_COLLECT_METADATA] = { .type = NLA_FLAG },
2183 	[IFLA_GRE_FWMARK]       = { .type = NLA_U32 },
2184 	[IFLA_GRE_ERSPAN_INDEX] = { .type = NLA_U32 },
2185 	[IFLA_GRE_ERSPAN_VER]	= { .type = NLA_U8 },
2186 	[IFLA_GRE_ERSPAN_DIR]	= { .type = NLA_U8 },
2187 	[IFLA_GRE_ERSPAN_HWID]	= { .type = NLA_U16 },
2188 };
2189 
2190 static void ip6erspan_tap_setup(struct net_device *dev)
2191 {
2192 	ether_setup(dev);
2193 
2194 	dev->max_mtu = 0;
2195 	dev->netdev_ops = &ip6erspan_netdev_ops;
2196 	dev->needs_free_netdev = true;
2197 	dev->priv_destructor = ip6gre_dev_free;
2198 
2199 	dev->pcpu_stat_type = NETDEV_PCPU_STAT_TSTATS;
2200 	dev->priv_flags &= ~IFF_TX_SKB_SHARING;
2201 	dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
2202 	netif_keep_dst(dev);
2203 }
2204 
2205 static int ip6erspan_newlink(struct net_device *dev,
2206 			     struct rtnl_newlink_params *params,
2207 			     struct netlink_ext_ack *extack)
2208 {
2209 	struct net *net = params->link_net ? : dev_net(dev);
2210 	struct ip6_tnl *nt = netdev_priv(dev);
2211 	struct nlattr **data = params->data;
2212 	struct nlattr **tb = params->tb;
2213 	struct ip6gre_net *ign;
2214 	int err;
2215 
2216 	ip6gre_netlink_parms(data, &nt->parms);
2217 	ip6erspan_set_version(data, &nt->parms);
2218 	ign = net_generic(net, ip6gre_net_id);
2219 
2220 	if (nt->parms.collect_md) {
2221 		if (rtnl_dereference(ign->collect_md_tun_erspan))
2222 			return -EEXIST;
2223 	} else {
2224 		if (ip6gre_tunnel_find(net, &nt->parms, dev->type))
2225 			return -EEXIST;
2226 	}
2227 
2228 	err = ip6gre_newlink_common(net, dev, tb, data, extack);
2229 	if (!err) {
2230 		ip6erspan_tnl_link_config(nt, !tb[IFLA_MTU]);
2231 		ip6erspan_tunnel_link_md(ign, nt);
2232 		ip6gre_tunnel_link(net_generic(net, ip6gre_net_id), nt);
2233 	}
2234 	return err;
2235 }
2236 
2237 static void ip6erspan_tnl_link_config(struct ip6_tnl *t, int set_mtu)
2238 {
2239 	ip6gre_tnl_link_config_common(t);
2240 	ip6gre_tnl_link_config_route(t, set_mtu, ip6erspan_calc_hlen(t));
2241 }
2242 
2243 static int ip6erspan_tnl_change(struct ip6_tnl *t,
2244 				const struct __ip6_tnl_parm *p, int set_mtu)
2245 {
2246 	ip6gre_tnl_copy_tnl_parm(t, p);
2247 	ip6erspan_tnl_link_config(t, set_mtu);
2248 	return 0;
2249 }
2250 
2251 static int ip6erspan_changelink(struct net_device *dev, struct nlattr *tb[],
2252 				struct nlattr *data[],
2253 				struct netlink_ext_ack *extack)
2254 {
2255 	struct ip6gre_net *ign = net_generic(dev_net(dev), ip6gre_net_id);
2256 	struct __ip6_tnl_parm p;
2257 	struct ip6_tnl *t;
2258 
2259 	t = ip6gre_changelink_common(dev, tb, data, &p, extack);
2260 	if (IS_ERR(t))
2261 		return PTR_ERR(t);
2262 
2263 	ip6erspan_set_version(data, &p);
2264 	ip6gre_tunnel_unlink_md(ign, t);
2265 	ip6gre_tunnel_unlink(ign, t);
2266 	ip6erspan_tnl_change(t, &p, !tb[IFLA_MTU]);
2267 	ip6erspan_tunnel_link_md(ign, t);
2268 	ip6gre_tunnel_link(ign, t);
2269 	return 0;
2270 }
2271 
2272 static struct rtnl_link_ops ip6gre_link_ops __read_mostly = {
2273 	.kind		= "ip6gre",
2274 	.maxtype	= IFLA_GRE_MAX,
2275 	.policy		= ip6gre_policy,
2276 	.priv_size	= sizeof(struct ip6_tnl),
2277 	.setup		= ip6gre_tunnel_setup,
2278 	.validate	= ip6gre_tunnel_validate,
2279 	.newlink	= ip6gre_newlink,
2280 	.changelink	= ip6gre_changelink,
2281 	.dellink	= ip6gre_dellink,
2282 	.get_size	= ip6gre_get_size,
2283 	.fill_info	= ip6gre_fill_info,
2284 	.get_link_net	= ip6_tnl_get_link_net,
2285 };
2286 
2287 static struct rtnl_link_ops ip6gre_tap_ops __read_mostly = {
2288 	.kind		= "ip6gretap",
2289 	.maxtype	= IFLA_GRE_MAX,
2290 	.policy		= ip6gre_policy,
2291 	.priv_size	= sizeof(struct ip6_tnl),
2292 	.setup		= ip6gre_tap_setup,
2293 	.validate	= ip6gre_tap_validate,
2294 	.newlink	= ip6gre_newlink,
2295 	.changelink	= ip6gre_changelink,
2296 	.get_size	= ip6gre_get_size,
2297 	.fill_info	= ip6gre_fill_info,
2298 	.get_link_net	= ip6_tnl_get_link_net,
2299 };
2300 
2301 static struct rtnl_link_ops ip6erspan_tap_ops __read_mostly = {
2302 	.kind		= "ip6erspan",
2303 	.maxtype	= IFLA_GRE_MAX,
2304 	.policy		= ip6gre_policy,
2305 	.priv_size	= sizeof(struct ip6_tnl),
2306 	.setup		= ip6erspan_tap_setup,
2307 	.validate	= ip6erspan_tap_validate,
2308 	.newlink	= ip6erspan_newlink,
2309 	.changelink	= ip6erspan_changelink,
2310 	.get_size	= ip6gre_get_size,
2311 	.fill_info	= ip6gre_fill_info,
2312 	.get_link_net	= ip6_tnl_get_link_net,
2313 };
2314 
2315 /*
2316  *	And now the modules code and kernel interface.
2317  */
2318 
2319 static int __init ip6gre_init(void)
2320 {
2321 	int err;
2322 
2323 	pr_info("GRE over IPv6 tunneling driver\n");
2324 
2325 	err = register_pernet_device(&ip6gre_net_ops);
2326 	if (err < 0)
2327 		return err;
2328 
2329 	err = inet6_add_protocol(&ip6gre_protocol, IPPROTO_GRE);
2330 	if (err < 0) {
2331 		pr_info("%s: can't add protocol\n", __func__);
2332 		goto add_proto_failed;
2333 	}
2334 
2335 	err = rtnl_link_register(&ip6gre_link_ops);
2336 	if (err < 0)
2337 		goto rtnl_link_failed;
2338 
2339 	err = rtnl_link_register(&ip6gre_tap_ops);
2340 	if (err < 0)
2341 		goto tap_ops_failed;
2342 
2343 	err = rtnl_link_register(&ip6erspan_tap_ops);
2344 	if (err < 0)
2345 		goto erspan_link_failed;
2346 
2347 out:
2348 	return err;
2349 
2350 erspan_link_failed:
2351 	rtnl_link_unregister(&ip6gre_tap_ops);
2352 tap_ops_failed:
2353 	rtnl_link_unregister(&ip6gre_link_ops);
2354 rtnl_link_failed:
2355 	inet6_del_protocol(&ip6gre_protocol, IPPROTO_GRE);
2356 add_proto_failed:
2357 	unregister_pernet_device(&ip6gre_net_ops);
2358 	goto out;
2359 }
2360 
2361 static void __exit ip6gre_fini(void)
2362 {
2363 	rtnl_link_unregister(&ip6gre_tap_ops);
2364 	rtnl_link_unregister(&ip6gre_link_ops);
2365 	rtnl_link_unregister(&ip6erspan_tap_ops);
2366 	inet6_del_protocol(&ip6gre_protocol, IPPROTO_GRE);
2367 	unregister_pernet_device(&ip6gre_net_ops);
2368 }
2369 
2370 module_init(ip6gre_init);
2371 module_exit(ip6gre_fini);
2372 MODULE_LICENSE("GPL");
2373 MODULE_AUTHOR("D. Kozlov <xeb@mail.ru>");
2374 MODULE_DESCRIPTION("GRE over IPv6 tunneling device");
2375 MODULE_ALIAS_RTNL_LINK("ip6gre");
2376 MODULE_ALIAS_RTNL_LINK("ip6gretap");
2377 MODULE_ALIAS_RTNL_LINK("ip6erspan");
2378 MODULE_ALIAS_NETDEV("ip6gre0");
2379