xref: /linux/net/ipv6/ip6_gre.c (revision a4ff64edf9edc8f05e2183610dc8306d3279c6ac)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *	GRE over IPv6 protocol decoder.
4  *
5  *	Authors: Dmitry Kozlov (xeb@mail.ru)
6  */
7 
8 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
9 
10 #include <linux/capability.h>
11 #include <linux/module.h>
12 #include <linux/types.h>
13 #include <linux/kernel.h>
14 #include <linux/slab.h>
15 #include <linux/uaccess.h>
16 #include <linux/skbuff.h>
17 #include <linux/netdevice.h>
18 #include <linux/in.h>
19 #include <linux/tcp.h>
20 #include <linux/udp.h>
21 #include <linux/if_arp.h>
22 #include <linux/init.h>
23 #include <linux/in6.h>
24 #include <linux/inetdevice.h>
25 #include <linux/igmp.h>
26 #include <linux/netfilter_ipv4.h>
27 #include <linux/etherdevice.h>
28 #include <linux/if_ether.h>
29 #include <linux/hash.h>
30 #include <linux/if_tunnel.h>
31 #include <linux/ip6_tunnel.h>
32 
33 #include <net/sock.h>
34 #include <net/ip.h>
35 #include <net/ip_tunnels.h>
36 #include <net/icmp.h>
37 #include <net/protocol.h>
38 #include <net/addrconf.h>
39 #include <net/arp.h>
40 #include <net/checksum.h>
41 #include <net/dsfield.h>
42 #include <net/inet_ecn.h>
43 #include <net/xfrm.h>
44 #include <net/net_namespace.h>
45 #include <net/netns/generic.h>
46 #include <net/rtnetlink.h>
47 
48 #include <net/ipv6.h>
49 #include <net/ip6_fib.h>
50 #include <net/ip6_route.h>
51 #include <net/ip6_tunnel.h>
52 #include <net/gre.h>
53 #include <net/erspan.h>
54 #include <net/dst_metadata.h>
55 
56 
57 static bool log_ecn_error = true;
58 module_param(log_ecn_error, bool, 0644);
59 MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN");
60 
61 #define IP6_GRE_HASH_SIZE_SHIFT  5
62 #define IP6_GRE_HASH_SIZE (1 << IP6_GRE_HASH_SIZE_SHIFT)
63 
64 static unsigned int ip6gre_net_id __read_mostly;
65 struct ip6gre_net {
66 	struct ip6_tnl __rcu *tunnels[4][IP6_GRE_HASH_SIZE];
67 
68 	struct ip6_tnl __rcu *collect_md_tun;
69 	struct ip6_tnl __rcu *collect_md_tun_erspan;
70 	struct net_device *fb_tunnel_dev;
71 };
72 
73 static struct rtnl_link_ops ip6gre_link_ops __read_mostly;
74 static struct rtnl_link_ops ip6gre_tap_ops __read_mostly;
75 static struct rtnl_link_ops ip6erspan_tap_ops __read_mostly;
76 static int ip6gre_tunnel_init(struct net_device *dev);
77 static void ip6gre_tunnel_setup(struct net_device *dev);
78 static void ip6gre_tunnel_link(struct ip6gre_net *ign, struct ip6_tnl *t);
79 static void ip6gre_tnl_link_config(struct ip6_tnl *t, int set_mtu);
80 static void ip6erspan_tnl_link_config(struct ip6_tnl *t, int set_mtu);
81 
82 /* Tunnel hash table */
83 
84 /*
85    4 hash tables:
86 
87    3: (remote,local)
88    2: (remote,*)
89    1: (*,local)
90    0: (*,*)
91 
92    We require exact key match i.e. if a key is present in packet
93    it will match only tunnel with the same key; if it is not present,
94    it will match only keyless tunnel.
95 
96    All keysless packets, if not matched configured keyless tunnels
97    will match fallback tunnel.
98  */
99 
100 #define HASH_KEY(key) (((__force u32)key^((__force u32)key>>4))&(IP6_GRE_HASH_SIZE - 1))
101 static u32 HASH_ADDR(const struct in6_addr *addr)
102 {
103 	u32 hash = ipv6_addr_hash(addr);
104 
105 	return hash_32(hash, IP6_GRE_HASH_SIZE_SHIFT);
106 }
107 
108 #define tunnels_r_l	tunnels[3]
109 #define tunnels_r	tunnels[2]
110 #define tunnels_l	tunnels[1]
111 #define tunnels_wc	tunnels[0]
112 
113 /* Given src, dst and key, find appropriate for input tunnel. */
114 
115 static struct ip6_tnl *ip6gre_tunnel_lookup(struct net_device *dev,
116 		const struct in6_addr *remote, const struct in6_addr *local,
117 		__be32 key, __be16 gre_proto)
118 {
119 	struct net *net = dev_net(dev);
120 	int link = dev->ifindex;
121 	unsigned int h0 = HASH_ADDR(remote);
122 	unsigned int h1 = HASH_KEY(key);
123 	struct ip6_tnl *t, *cand = NULL;
124 	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
125 	int dev_type = (gre_proto == htons(ETH_P_TEB) ||
126 			gre_proto == htons(ETH_P_ERSPAN) ||
127 			gre_proto == htons(ETH_P_ERSPAN2)) ?
128 		       ARPHRD_ETHER : ARPHRD_IP6GRE;
129 	int score, cand_score = 4;
130 	struct net_device *ndev;
131 
132 	for_each_ip_tunnel_rcu(t, ign->tunnels_r_l[h0 ^ h1]) {
133 		if (!ipv6_addr_equal(local, &t->parms.laddr) ||
134 		    !ipv6_addr_equal(remote, &t->parms.raddr) ||
135 		    key != t->parms.i_key ||
136 		    !(t->dev->flags & IFF_UP))
137 			continue;
138 
139 		if (t->dev->type != ARPHRD_IP6GRE &&
140 		    t->dev->type != dev_type)
141 			continue;
142 
143 		score = 0;
144 		if (t->parms.link != link)
145 			score |= 1;
146 		if (t->dev->type != dev_type)
147 			score |= 2;
148 		if (score == 0)
149 			return t;
150 
151 		if (score < cand_score) {
152 			cand = t;
153 			cand_score = score;
154 		}
155 	}
156 
157 	for_each_ip_tunnel_rcu(t, ign->tunnels_r[h0 ^ h1]) {
158 		if (!ipv6_addr_equal(remote, &t->parms.raddr) ||
159 		    key != t->parms.i_key ||
160 		    !(t->dev->flags & IFF_UP))
161 			continue;
162 
163 		if (t->dev->type != ARPHRD_IP6GRE &&
164 		    t->dev->type != dev_type)
165 			continue;
166 
167 		score = 0;
168 		if (t->parms.link != link)
169 			score |= 1;
170 		if (t->dev->type != dev_type)
171 			score |= 2;
172 		if (score == 0)
173 			return t;
174 
175 		if (score < cand_score) {
176 			cand = t;
177 			cand_score = score;
178 		}
179 	}
180 
181 	for_each_ip_tunnel_rcu(t, ign->tunnels_l[h1]) {
182 		if ((!ipv6_addr_equal(local, &t->parms.laddr) &&
183 			  (!ipv6_addr_equal(local, &t->parms.raddr) ||
184 				 !ipv6_addr_is_multicast(local))) ||
185 		    key != t->parms.i_key ||
186 		    !(t->dev->flags & IFF_UP))
187 			continue;
188 
189 		if (t->dev->type != ARPHRD_IP6GRE &&
190 		    t->dev->type != dev_type)
191 			continue;
192 
193 		score = 0;
194 		if (t->parms.link != link)
195 			score |= 1;
196 		if (t->dev->type != dev_type)
197 			score |= 2;
198 		if (score == 0)
199 			return t;
200 
201 		if (score < cand_score) {
202 			cand = t;
203 			cand_score = score;
204 		}
205 	}
206 
207 	for_each_ip_tunnel_rcu(t, ign->tunnels_wc[h1]) {
208 		if (t->parms.i_key != key ||
209 		    !(t->dev->flags & IFF_UP))
210 			continue;
211 
212 		if (t->dev->type != ARPHRD_IP6GRE &&
213 		    t->dev->type != dev_type)
214 			continue;
215 
216 		score = 0;
217 		if (t->parms.link != link)
218 			score |= 1;
219 		if (t->dev->type != dev_type)
220 			score |= 2;
221 		if (score == 0)
222 			return t;
223 
224 		if (score < cand_score) {
225 			cand = t;
226 			cand_score = score;
227 		}
228 	}
229 
230 	if (cand)
231 		return cand;
232 
233 	if (gre_proto == htons(ETH_P_ERSPAN) ||
234 	    gre_proto == htons(ETH_P_ERSPAN2))
235 		t = rcu_dereference(ign->collect_md_tun_erspan);
236 	else
237 		t = rcu_dereference(ign->collect_md_tun);
238 
239 	if (t && t->dev->flags & IFF_UP)
240 		return t;
241 
242 	ndev = READ_ONCE(ign->fb_tunnel_dev);
243 	if (ndev && ndev->flags & IFF_UP)
244 		return netdev_priv(ndev);
245 
246 	return NULL;
247 }
248 
249 static struct ip6_tnl __rcu **__ip6gre_bucket(struct ip6gre_net *ign,
250 		const struct __ip6_tnl_parm *p)
251 {
252 	const struct in6_addr *remote = &p->raddr;
253 	const struct in6_addr *local = &p->laddr;
254 	unsigned int h = HASH_KEY(p->i_key);
255 	int prio = 0;
256 
257 	if (!ipv6_addr_any(local))
258 		prio |= 1;
259 	if (!ipv6_addr_any(remote) && !ipv6_addr_is_multicast(remote)) {
260 		prio |= 2;
261 		h ^= HASH_ADDR(remote);
262 	}
263 
264 	return &ign->tunnels[prio][h];
265 }
266 
267 static void ip6gre_tunnel_link_md(struct ip6gre_net *ign, struct ip6_tnl *t)
268 {
269 	if (t->parms.collect_md)
270 		rcu_assign_pointer(ign->collect_md_tun, t);
271 }
272 
273 static void ip6erspan_tunnel_link_md(struct ip6gre_net *ign, struct ip6_tnl *t)
274 {
275 	if (t->parms.collect_md)
276 		rcu_assign_pointer(ign->collect_md_tun_erspan, t);
277 }
278 
279 static void ip6gre_tunnel_unlink_md(struct ip6gre_net *ign, struct ip6_tnl *t)
280 {
281 	if (t->parms.collect_md)
282 		rcu_assign_pointer(ign->collect_md_tun, NULL);
283 }
284 
285 static void ip6erspan_tunnel_unlink_md(struct ip6gre_net *ign,
286 				       struct ip6_tnl *t)
287 {
288 	if (t->parms.collect_md)
289 		rcu_assign_pointer(ign->collect_md_tun_erspan, NULL);
290 }
291 
292 static inline struct ip6_tnl __rcu **ip6gre_bucket(struct ip6gre_net *ign,
293 		const struct ip6_tnl *t)
294 {
295 	return __ip6gre_bucket(ign, &t->parms);
296 }
297 
298 static void ip6gre_tunnel_link(struct ip6gre_net *ign, struct ip6_tnl *t)
299 {
300 	struct ip6_tnl __rcu **tp = ip6gre_bucket(ign, t);
301 
302 	rcu_assign_pointer(t->next, rtnl_dereference(*tp));
303 	rcu_assign_pointer(*tp, t);
304 }
305 
306 static void ip6gre_tunnel_unlink(struct ip6gre_net *ign, struct ip6_tnl *t)
307 {
308 	struct ip6_tnl __rcu **tp;
309 	struct ip6_tnl *iter;
310 
311 	for (tp = ip6gre_bucket(ign, t);
312 	     (iter = rtnl_dereference(*tp)) != NULL;
313 	     tp = &iter->next) {
314 		if (t == iter) {
315 			rcu_assign_pointer(*tp, t->next);
316 			break;
317 		}
318 	}
319 }
320 
321 static struct ip6_tnl *ip6gre_tunnel_find(struct net *net,
322 					   const struct __ip6_tnl_parm *parms,
323 					   int type)
324 {
325 	const struct in6_addr *remote = &parms->raddr;
326 	const struct in6_addr *local = &parms->laddr;
327 	__be32 key = parms->i_key;
328 	int link = parms->link;
329 	struct ip6_tnl *t;
330 	struct ip6_tnl __rcu **tp;
331 	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
332 
333 	for (tp = __ip6gre_bucket(ign, parms);
334 	     (t = rtnl_dereference(*tp)) != NULL;
335 	     tp = &t->next)
336 		if (ipv6_addr_equal(local, &t->parms.laddr) &&
337 		    ipv6_addr_equal(remote, &t->parms.raddr) &&
338 		    key == t->parms.i_key &&
339 		    link == t->parms.link &&
340 		    type == t->dev->type)
341 			break;
342 
343 	return t;
344 }
345 
346 static struct ip6_tnl *ip6gre_tunnel_locate(struct net *net,
347 		const struct __ip6_tnl_parm *parms, int create)
348 {
349 	struct ip6_tnl *t, *nt;
350 	struct net_device *dev;
351 	char name[IFNAMSIZ];
352 	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
353 
354 	t = ip6gre_tunnel_find(net, parms, ARPHRD_IP6GRE);
355 	if (t && create)
356 		return NULL;
357 	if (t || !create)
358 		return t;
359 
360 	if (parms->name[0]) {
361 		if (!dev_valid_name(parms->name))
362 			return NULL;
363 		strscpy(name, parms->name, IFNAMSIZ);
364 	} else {
365 		strcpy(name, "ip6gre%d");
366 	}
367 	dev = alloc_netdev(sizeof(*t), name, NET_NAME_UNKNOWN,
368 			   ip6gre_tunnel_setup);
369 	if (!dev)
370 		return NULL;
371 
372 	dev_net_set(dev, net);
373 
374 	nt = netdev_priv(dev);
375 	nt->parms = *parms;
376 	dev->rtnl_link_ops = &ip6gre_link_ops;
377 
378 	nt->dev = dev;
379 	nt->net = dev_net(dev);
380 
381 	if (register_netdevice(dev) < 0)
382 		goto failed_free;
383 
384 	ip6gre_tnl_link_config(nt, 1);
385 	ip6gre_tunnel_link(ign, nt);
386 	return nt;
387 
388 failed_free:
389 	free_netdev(dev);
390 	return NULL;
391 }
392 
393 static void ip6erspan_tunnel_uninit(struct net_device *dev)
394 {
395 	struct ip6_tnl *t = netdev_priv(dev);
396 	struct ip6gre_net *ign = net_generic(t->net, ip6gre_net_id);
397 
398 	ip6erspan_tunnel_unlink_md(ign, t);
399 	ip6gre_tunnel_unlink(ign, t);
400 	dst_cache_reset(&t->dst_cache);
401 	netdev_put(dev, &t->dev_tracker);
402 }
403 
404 static void ip6gre_tunnel_uninit(struct net_device *dev)
405 {
406 	struct ip6_tnl *t = netdev_priv(dev);
407 	struct ip6gre_net *ign = net_generic(t->net, ip6gre_net_id);
408 
409 	ip6gre_tunnel_unlink_md(ign, t);
410 	ip6gre_tunnel_unlink(ign, t);
411 	if (ign->fb_tunnel_dev == dev)
412 		WRITE_ONCE(ign->fb_tunnel_dev, NULL);
413 	dst_cache_reset(&t->dst_cache);
414 	netdev_put(dev, &t->dev_tracker);
415 }
416 
417 
418 static int ip6gre_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
419 		       u8 type, u8 code, int offset, __be32 info)
420 {
421 	struct net *net = dev_net(skb->dev);
422 	const struct ipv6hdr *ipv6h;
423 	struct tnl_ptk_info tpi;
424 	struct ip6_tnl *t;
425 
426 	if (gre_parse_header(skb, &tpi, NULL, htons(ETH_P_IPV6),
427 			     offset) < 0)
428 		return -EINVAL;
429 
430 	ipv6h = (const struct ipv6hdr *)skb->data;
431 	t = ip6gre_tunnel_lookup(skb->dev, &ipv6h->daddr, &ipv6h->saddr,
432 				 tpi.key, tpi.proto);
433 	if (!t)
434 		return -ENOENT;
435 
436 	switch (type) {
437 	case ICMPV6_DEST_UNREACH:
438 		net_dbg_ratelimited("%s: Path to destination invalid or inactive!\n",
439 				    t->parms.name);
440 		if (code != ICMPV6_PORT_UNREACH)
441 			break;
442 		return 0;
443 	case ICMPV6_TIME_EXCEED:
444 		if (code == ICMPV6_EXC_HOPLIMIT) {
445 			net_dbg_ratelimited("%s: Too small hop limit or routing loop in tunnel!\n",
446 					    t->parms.name);
447 			break;
448 		}
449 		return 0;
450 	case ICMPV6_PARAMPROB: {
451 		struct ipv6_tlv_tnl_enc_lim *tel;
452 		__u32 teli;
453 
454 		teli = 0;
455 		if (code == ICMPV6_HDR_FIELD)
456 			teli = ip6_tnl_parse_tlv_enc_lim(skb, skb->data);
457 
458 		if (teli && teli == be32_to_cpu(info) - 2) {
459 			tel = (struct ipv6_tlv_tnl_enc_lim *) &skb->data[teli];
460 			if (tel->encap_limit == 0) {
461 				net_dbg_ratelimited("%s: Too small encapsulation limit or routing loop in tunnel!\n",
462 						    t->parms.name);
463 			}
464 		} else {
465 			net_dbg_ratelimited("%s: Recipient unable to parse tunneled packet!\n",
466 					    t->parms.name);
467 		}
468 		return 0;
469 	}
470 	case ICMPV6_PKT_TOOBIG:
471 		ip6_update_pmtu(skb, net, info, 0, 0, sock_net_uid(net, NULL));
472 		return 0;
473 	case NDISC_REDIRECT:
474 		ip6_redirect(skb, net, skb->dev->ifindex, 0,
475 			     sock_net_uid(net, NULL));
476 		return 0;
477 	}
478 
479 	if (time_before(jiffies, t->err_time + IP6TUNNEL_ERR_TIMEO))
480 		t->err_count++;
481 	else
482 		t->err_count = 1;
483 	t->err_time = jiffies;
484 
485 	return 0;
486 }
487 
488 static int ip6gre_rcv(struct sk_buff *skb, const struct tnl_ptk_info *tpi)
489 {
490 	const struct ipv6hdr *ipv6h;
491 	struct ip6_tnl *tunnel;
492 
493 	ipv6h = ipv6_hdr(skb);
494 	tunnel = ip6gre_tunnel_lookup(skb->dev,
495 				      &ipv6h->saddr, &ipv6h->daddr, tpi->key,
496 				      tpi->proto);
497 	if (tunnel) {
498 		if (tunnel->parms.collect_md) {
499 			struct metadata_dst *tun_dst;
500 			__be64 tun_id;
501 			__be16 flags;
502 
503 			flags = tpi->flags;
504 			tun_id = key32_to_tunnel_id(tpi->key);
505 
506 			tun_dst = ipv6_tun_rx_dst(skb, flags, tun_id, 0);
507 			if (!tun_dst)
508 				return PACKET_REJECT;
509 
510 			ip6_tnl_rcv(tunnel, skb, tpi, tun_dst, log_ecn_error);
511 		} else {
512 			ip6_tnl_rcv(tunnel, skb, tpi, NULL, log_ecn_error);
513 		}
514 
515 		return PACKET_RCVD;
516 	}
517 
518 	return PACKET_REJECT;
519 }
520 
521 static int ip6erspan_rcv(struct sk_buff *skb,
522 			 struct tnl_ptk_info *tpi,
523 			 int gre_hdr_len)
524 {
525 	struct erspan_base_hdr *ershdr;
526 	const struct ipv6hdr *ipv6h;
527 	struct erspan_md2 *md2;
528 	struct ip6_tnl *tunnel;
529 	u8 ver;
530 
531 	ipv6h = ipv6_hdr(skb);
532 	ershdr = (struct erspan_base_hdr *)skb->data;
533 	ver = ershdr->ver;
534 
535 	tunnel = ip6gre_tunnel_lookup(skb->dev,
536 				      &ipv6h->saddr, &ipv6h->daddr, tpi->key,
537 				      tpi->proto);
538 	if (tunnel) {
539 		int len = erspan_hdr_len(ver);
540 
541 		if (unlikely(!pskb_may_pull(skb, len)))
542 			return PACKET_REJECT;
543 
544 		if (__iptunnel_pull_header(skb, len,
545 					   htons(ETH_P_TEB),
546 					   false, false) < 0)
547 			return PACKET_REJECT;
548 
549 		if (tunnel->parms.collect_md) {
550 			struct erspan_metadata *pkt_md, *md;
551 			struct metadata_dst *tun_dst;
552 			struct ip_tunnel_info *info;
553 			unsigned char *gh;
554 			__be64 tun_id;
555 			__be16 flags;
556 
557 			tpi->flags |= TUNNEL_KEY;
558 			flags = tpi->flags;
559 			tun_id = key32_to_tunnel_id(tpi->key);
560 
561 			tun_dst = ipv6_tun_rx_dst(skb, flags, tun_id,
562 						  sizeof(*md));
563 			if (!tun_dst)
564 				return PACKET_REJECT;
565 
566 			/* skb can be uncloned in __iptunnel_pull_header, so
567 			 * old pkt_md is no longer valid and we need to reset
568 			 * it
569 			 */
570 			gh = skb_network_header(skb) +
571 			     skb_network_header_len(skb);
572 			pkt_md = (struct erspan_metadata *)(gh + gre_hdr_len +
573 							    sizeof(*ershdr));
574 			info = &tun_dst->u.tun_info;
575 			md = ip_tunnel_info_opts(info);
576 			md->version = ver;
577 			md2 = &md->u.md2;
578 			memcpy(md2, pkt_md, ver == 1 ? ERSPAN_V1_MDSIZE :
579 						       ERSPAN_V2_MDSIZE);
580 			info->key.tun_flags |= TUNNEL_ERSPAN_OPT;
581 			info->options_len = sizeof(*md);
582 
583 			ip6_tnl_rcv(tunnel, skb, tpi, tun_dst, log_ecn_error);
584 
585 		} else {
586 			ip6_tnl_rcv(tunnel, skb, tpi, NULL, log_ecn_error);
587 		}
588 
589 		return PACKET_RCVD;
590 	}
591 
592 	return PACKET_REJECT;
593 }
594 
595 static int gre_rcv(struct sk_buff *skb)
596 {
597 	struct tnl_ptk_info tpi;
598 	bool csum_err = false;
599 	int hdr_len;
600 
601 	hdr_len = gre_parse_header(skb, &tpi, &csum_err, htons(ETH_P_IPV6), 0);
602 	if (hdr_len < 0)
603 		goto drop;
604 
605 	if (iptunnel_pull_header(skb, hdr_len, tpi.proto, false))
606 		goto drop;
607 
608 	if (unlikely(tpi.proto == htons(ETH_P_ERSPAN) ||
609 		     tpi.proto == htons(ETH_P_ERSPAN2))) {
610 		if (ip6erspan_rcv(skb, &tpi, hdr_len) == PACKET_RCVD)
611 			return 0;
612 		goto out;
613 	}
614 
615 	if (ip6gre_rcv(skb, &tpi) == PACKET_RCVD)
616 		return 0;
617 
618 out:
619 	icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0);
620 drop:
621 	kfree_skb(skb);
622 	return 0;
623 }
624 
625 static int gre_handle_offloads(struct sk_buff *skb, bool csum)
626 {
627 	return iptunnel_handle_offloads(skb,
628 					csum ? SKB_GSO_GRE_CSUM : SKB_GSO_GRE);
629 }
630 
631 static void prepare_ip6gre_xmit_ipv4(struct sk_buff *skb,
632 				     struct net_device *dev,
633 				     struct flowi6 *fl6, __u8 *dsfield,
634 				     int *encap_limit)
635 {
636 	const struct iphdr *iph = ip_hdr(skb);
637 	struct ip6_tnl *t = netdev_priv(dev);
638 
639 	if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
640 		*encap_limit = t->parms.encap_limit;
641 
642 	memcpy(fl6, &t->fl.u.ip6, sizeof(*fl6));
643 
644 	if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
645 		*dsfield = ipv4_get_dsfield(iph);
646 	else
647 		*dsfield = ip6_tclass(t->parms.flowinfo);
648 
649 	if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
650 		fl6->flowi6_mark = skb->mark;
651 	else
652 		fl6->flowi6_mark = t->parms.fwmark;
653 
654 	fl6->flowi6_uid = sock_net_uid(dev_net(dev), NULL);
655 }
656 
657 static int prepare_ip6gre_xmit_ipv6(struct sk_buff *skb,
658 				    struct net_device *dev,
659 				    struct flowi6 *fl6, __u8 *dsfield,
660 				    int *encap_limit)
661 {
662 	struct ipv6hdr *ipv6h;
663 	struct ip6_tnl *t = netdev_priv(dev);
664 	__u16 offset;
665 
666 	offset = ip6_tnl_parse_tlv_enc_lim(skb, skb_network_header(skb));
667 	/* ip6_tnl_parse_tlv_enc_lim() might have reallocated skb->head */
668 	ipv6h = ipv6_hdr(skb);
669 
670 	if (offset > 0) {
671 		struct ipv6_tlv_tnl_enc_lim *tel;
672 
673 		tel = (struct ipv6_tlv_tnl_enc_lim *)&skb_network_header(skb)[offset];
674 		if (tel->encap_limit == 0) {
675 			icmpv6_ndo_send(skb, ICMPV6_PARAMPROB,
676 					ICMPV6_HDR_FIELD, offset + 2);
677 			return -1;
678 		}
679 		*encap_limit = tel->encap_limit - 1;
680 	} else if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) {
681 		*encap_limit = t->parms.encap_limit;
682 	}
683 
684 	memcpy(fl6, &t->fl.u.ip6, sizeof(*fl6));
685 
686 	if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
687 		*dsfield = ipv6_get_dsfield(ipv6h);
688 	else
689 		*dsfield = ip6_tclass(t->parms.flowinfo);
690 
691 	if (t->parms.flags & IP6_TNL_F_USE_ORIG_FLOWLABEL)
692 		fl6->flowlabel |= ip6_flowlabel(ipv6h);
693 
694 	if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
695 		fl6->flowi6_mark = skb->mark;
696 	else
697 		fl6->flowi6_mark = t->parms.fwmark;
698 
699 	fl6->flowi6_uid = sock_net_uid(dev_net(dev), NULL);
700 
701 	return 0;
702 }
703 
704 static int prepare_ip6gre_xmit_other(struct sk_buff *skb,
705 				     struct net_device *dev,
706 				     struct flowi6 *fl6, __u8 *dsfield,
707 				     int *encap_limit)
708 {
709 	struct ip6_tnl *t = netdev_priv(dev);
710 
711 	if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
712 		*encap_limit = t->parms.encap_limit;
713 
714 	memcpy(fl6, &t->fl.u.ip6, sizeof(*fl6));
715 
716 	if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
717 		*dsfield = 0;
718 	else
719 		*dsfield = ip6_tclass(t->parms.flowinfo);
720 
721 	if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
722 		fl6->flowi6_mark = skb->mark;
723 	else
724 		fl6->flowi6_mark = t->parms.fwmark;
725 
726 	fl6->flowi6_uid = sock_net_uid(dev_net(dev), NULL);
727 
728 	return 0;
729 }
730 
731 static struct ip_tunnel_info *skb_tunnel_info_txcheck(struct sk_buff *skb)
732 {
733 	struct ip_tunnel_info *tun_info;
734 
735 	tun_info = skb_tunnel_info(skb);
736 	if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX)))
737 		return ERR_PTR(-EINVAL);
738 
739 	return tun_info;
740 }
741 
742 static netdev_tx_t __gre6_xmit(struct sk_buff *skb,
743 			       struct net_device *dev, __u8 dsfield,
744 			       struct flowi6 *fl6, int encap_limit,
745 			       __u32 *pmtu, __be16 proto)
746 {
747 	struct ip6_tnl *tunnel = netdev_priv(dev);
748 	__be16 protocol;
749 	__be16 flags;
750 
751 	if (dev->type == ARPHRD_ETHER)
752 		IPCB(skb)->flags = 0;
753 
754 	if (dev->header_ops && dev->type == ARPHRD_IP6GRE)
755 		fl6->daddr = ((struct ipv6hdr *)skb->data)->daddr;
756 	else
757 		fl6->daddr = tunnel->parms.raddr;
758 
759 	/* Push GRE header. */
760 	protocol = (dev->type == ARPHRD_ETHER) ? htons(ETH_P_TEB) : proto;
761 
762 	if (tunnel->parms.collect_md) {
763 		struct ip_tunnel_info *tun_info;
764 		const struct ip_tunnel_key *key;
765 		int tun_hlen;
766 
767 		tun_info = skb_tunnel_info_txcheck(skb);
768 		if (IS_ERR(tun_info) ||
769 		    unlikely(ip_tunnel_info_af(tun_info) != AF_INET6))
770 			return -EINVAL;
771 
772 		key = &tun_info->key;
773 		memset(fl6, 0, sizeof(*fl6));
774 		fl6->flowi6_proto = IPPROTO_GRE;
775 		fl6->daddr = key->u.ipv6.dst;
776 		fl6->flowlabel = key->label;
777 		fl6->flowi6_uid = sock_net_uid(dev_net(dev), NULL);
778 		fl6->fl6_gre_key = tunnel_id_to_key32(key->tun_id);
779 
780 		dsfield = key->tos;
781 		flags = key->tun_flags &
782 			(TUNNEL_CSUM | TUNNEL_KEY | TUNNEL_SEQ);
783 		tun_hlen = gre_calc_hlen(flags);
784 
785 		if (skb_cow_head(skb, dev->needed_headroom ?: tun_hlen + tunnel->encap_hlen))
786 			return -ENOMEM;
787 
788 		gre_build_header(skb, tun_hlen,
789 				 flags, protocol,
790 				 tunnel_id_to_key32(tun_info->key.tun_id),
791 				 (flags & TUNNEL_SEQ) ? htonl(atomic_fetch_inc(&tunnel->o_seqno))
792 						      : 0);
793 
794 	} else {
795 		if (skb_cow_head(skb, dev->needed_headroom ?: tunnel->hlen))
796 			return -ENOMEM;
797 
798 		flags = tunnel->parms.o_flags;
799 
800 		gre_build_header(skb, tunnel->tun_hlen, flags,
801 				 protocol, tunnel->parms.o_key,
802 				 (flags & TUNNEL_SEQ) ? htonl(atomic_fetch_inc(&tunnel->o_seqno))
803 						      : 0);
804 	}
805 
806 	return ip6_tnl_xmit(skb, dev, dsfield, fl6, encap_limit, pmtu,
807 			    NEXTHDR_GRE);
808 }
809 
810 static inline int ip6gre_xmit_ipv4(struct sk_buff *skb, struct net_device *dev)
811 {
812 	struct ip6_tnl *t = netdev_priv(dev);
813 	int encap_limit = -1;
814 	struct flowi6 fl6;
815 	__u8 dsfield = 0;
816 	__u32 mtu;
817 	int err;
818 
819 	memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
820 
821 	if (!t->parms.collect_md)
822 		prepare_ip6gre_xmit_ipv4(skb, dev, &fl6,
823 					 &dsfield, &encap_limit);
824 
825 	err = gre_handle_offloads(skb, !!(t->parms.o_flags & TUNNEL_CSUM));
826 	if (err)
827 		return -1;
828 
829 	err = __gre6_xmit(skb, dev, dsfield, &fl6, encap_limit, &mtu,
830 			  skb->protocol);
831 	if (err != 0) {
832 		/* XXX: send ICMP error even if DF is not set. */
833 		if (err == -EMSGSIZE)
834 			icmp_ndo_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
835 				      htonl(mtu));
836 		return -1;
837 	}
838 
839 	return 0;
840 }
841 
842 static inline int ip6gre_xmit_ipv6(struct sk_buff *skb, struct net_device *dev)
843 {
844 	struct ip6_tnl *t = netdev_priv(dev);
845 	struct ipv6hdr *ipv6h = ipv6_hdr(skb);
846 	int encap_limit = -1;
847 	struct flowi6 fl6;
848 	__u8 dsfield = 0;
849 	__u32 mtu;
850 	int err;
851 
852 	if (ipv6_addr_equal(&t->parms.raddr, &ipv6h->saddr))
853 		return -1;
854 
855 	if (!t->parms.collect_md &&
856 	    prepare_ip6gre_xmit_ipv6(skb, dev, &fl6, &dsfield, &encap_limit))
857 		return -1;
858 
859 	if (gre_handle_offloads(skb, !!(t->parms.o_flags & TUNNEL_CSUM)))
860 		return -1;
861 
862 	err = __gre6_xmit(skb, dev, dsfield, &fl6, encap_limit,
863 			  &mtu, skb->protocol);
864 	if (err != 0) {
865 		if (err == -EMSGSIZE)
866 			icmpv6_ndo_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
867 		return -1;
868 	}
869 
870 	return 0;
871 }
872 
873 static int ip6gre_xmit_other(struct sk_buff *skb, struct net_device *dev)
874 {
875 	struct ip6_tnl *t = netdev_priv(dev);
876 	int encap_limit = -1;
877 	struct flowi6 fl6;
878 	__u8 dsfield = 0;
879 	__u32 mtu;
880 	int err;
881 
882 	if (!t->parms.collect_md &&
883 	    prepare_ip6gre_xmit_other(skb, dev, &fl6, &dsfield, &encap_limit))
884 		return -1;
885 
886 	err = gre_handle_offloads(skb, !!(t->parms.o_flags & TUNNEL_CSUM));
887 	if (err)
888 		return err;
889 	err = __gre6_xmit(skb, dev, dsfield, &fl6, encap_limit, &mtu, skb->protocol);
890 
891 	return err;
892 }
893 
894 static netdev_tx_t ip6gre_tunnel_xmit(struct sk_buff *skb,
895 	struct net_device *dev)
896 {
897 	struct ip6_tnl *t = netdev_priv(dev);
898 	__be16 payload_protocol;
899 	int ret;
900 
901 	if (!pskb_inet_may_pull(skb))
902 		goto tx_err;
903 
904 	if (!ip6_tnl_xmit_ctl(t, &t->parms.laddr, &t->parms.raddr))
905 		goto tx_err;
906 
907 	payload_protocol = skb_protocol(skb, true);
908 	switch (payload_protocol) {
909 	case htons(ETH_P_IP):
910 		ret = ip6gre_xmit_ipv4(skb, dev);
911 		break;
912 	case htons(ETH_P_IPV6):
913 		ret = ip6gre_xmit_ipv6(skb, dev);
914 		break;
915 	default:
916 		ret = ip6gre_xmit_other(skb, dev);
917 		break;
918 	}
919 
920 	if (ret < 0)
921 		goto tx_err;
922 
923 	return NETDEV_TX_OK;
924 
925 tx_err:
926 	if (!t->parms.collect_md || !IS_ERR(skb_tunnel_info_txcheck(skb)))
927 		DEV_STATS_INC(dev, tx_errors);
928 	DEV_STATS_INC(dev, tx_dropped);
929 	kfree_skb(skb);
930 	return NETDEV_TX_OK;
931 }
932 
933 static netdev_tx_t ip6erspan_tunnel_xmit(struct sk_buff *skb,
934 					 struct net_device *dev)
935 {
936 	struct ip_tunnel_info *tun_info = NULL;
937 	struct ip6_tnl *t = netdev_priv(dev);
938 	struct dst_entry *dst = skb_dst(skb);
939 	bool truncate = false;
940 	int encap_limit = -1;
941 	__u8 dsfield = false;
942 	struct flowi6 fl6;
943 	int err = -EINVAL;
944 	__be16 proto;
945 	__u32 mtu;
946 	int nhoff;
947 
948 	if (!pskb_inet_may_pull(skb))
949 		goto tx_err;
950 
951 	if (!ip6_tnl_xmit_ctl(t, &t->parms.laddr, &t->parms.raddr))
952 		goto tx_err;
953 
954 	if (gre_handle_offloads(skb, false))
955 		goto tx_err;
956 
957 	if (skb->len > dev->mtu + dev->hard_header_len) {
958 		if (pskb_trim(skb, dev->mtu + dev->hard_header_len))
959 			goto tx_err;
960 		truncate = true;
961 	}
962 
963 	nhoff = skb_network_offset(skb);
964 	if (skb->protocol == htons(ETH_P_IP) &&
965 	    (ntohs(ip_hdr(skb)->tot_len) > skb->len - nhoff))
966 		truncate = true;
967 
968 	if (skb->protocol == htons(ETH_P_IPV6)) {
969 		int thoff;
970 
971 		if (skb_transport_header_was_set(skb))
972 			thoff = skb_transport_offset(skb);
973 		else
974 			thoff = nhoff + sizeof(struct ipv6hdr);
975 		if (ntohs(ipv6_hdr(skb)->payload_len) > skb->len - thoff)
976 			truncate = true;
977 	}
978 
979 	if (skb_cow_head(skb, dev->needed_headroom ?: t->hlen))
980 		goto tx_err;
981 
982 	t->parms.o_flags &= ~TUNNEL_KEY;
983 	IPCB(skb)->flags = 0;
984 
985 	/* For collect_md mode, derive fl6 from the tunnel key,
986 	 * for native mode, call prepare_ip6gre_xmit_{ipv4,ipv6}.
987 	 */
988 	if (t->parms.collect_md) {
989 		const struct ip_tunnel_key *key;
990 		struct erspan_metadata *md;
991 		__be32 tun_id;
992 
993 		tun_info = skb_tunnel_info_txcheck(skb);
994 		if (IS_ERR(tun_info) ||
995 		    unlikely(ip_tunnel_info_af(tun_info) != AF_INET6))
996 			goto tx_err;
997 
998 		key = &tun_info->key;
999 		memset(&fl6, 0, sizeof(fl6));
1000 		fl6.flowi6_proto = IPPROTO_GRE;
1001 		fl6.daddr = key->u.ipv6.dst;
1002 		fl6.flowlabel = key->label;
1003 		fl6.flowi6_uid = sock_net_uid(dev_net(dev), NULL);
1004 		fl6.fl6_gre_key = tunnel_id_to_key32(key->tun_id);
1005 
1006 		dsfield = key->tos;
1007 		if (!(tun_info->key.tun_flags & TUNNEL_ERSPAN_OPT))
1008 			goto tx_err;
1009 		if (tun_info->options_len < sizeof(*md))
1010 			goto tx_err;
1011 		md = ip_tunnel_info_opts(tun_info);
1012 
1013 		tun_id = tunnel_id_to_key32(key->tun_id);
1014 		if (md->version == 1) {
1015 			erspan_build_header(skb,
1016 					    ntohl(tun_id),
1017 					    ntohl(md->u.index), truncate,
1018 					    false);
1019 			proto = htons(ETH_P_ERSPAN);
1020 		} else if (md->version == 2) {
1021 			erspan_build_header_v2(skb,
1022 					       ntohl(tun_id),
1023 					       md->u.md2.dir,
1024 					       get_hwid(&md->u.md2),
1025 					       truncate, false);
1026 			proto = htons(ETH_P_ERSPAN2);
1027 		} else {
1028 			goto tx_err;
1029 		}
1030 	} else {
1031 		switch (skb->protocol) {
1032 		case htons(ETH_P_IP):
1033 			memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
1034 			prepare_ip6gre_xmit_ipv4(skb, dev, &fl6,
1035 						 &dsfield, &encap_limit);
1036 			break;
1037 		case htons(ETH_P_IPV6):
1038 			if (ipv6_addr_equal(&t->parms.raddr, &ipv6_hdr(skb)->saddr))
1039 				goto tx_err;
1040 			if (prepare_ip6gre_xmit_ipv6(skb, dev, &fl6,
1041 						     &dsfield, &encap_limit))
1042 				goto tx_err;
1043 			break;
1044 		default:
1045 			memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6));
1046 			break;
1047 		}
1048 
1049 		if (t->parms.erspan_ver == 1) {
1050 			erspan_build_header(skb, ntohl(t->parms.o_key),
1051 					    t->parms.index,
1052 					    truncate, false);
1053 			proto = htons(ETH_P_ERSPAN);
1054 		} else if (t->parms.erspan_ver == 2) {
1055 			erspan_build_header_v2(skb, ntohl(t->parms.o_key),
1056 					       t->parms.dir,
1057 					       t->parms.hwid,
1058 					       truncate, false);
1059 			proto = htons(ETH_P_ERSPAN2);
1060 		} else {
1061 			goto tx_err;
1062 		}
1063 
1064 		fl6.daddr = t->parms.raddr;
1065 	}
1066 
1067 	/* Push GRE header. */
1068 	gre_build_header(skb, 8, TUNNEL_SEQ, proto, 0, htonl(atomic_fetch_inc(&t->o_seqno)));
1069 
1070 	/* TooBig packet may have updated dst->dev's mtu */
1071 	if (!t->parms.collect_md && dst && dst_mtu(dst) > dst->dev->mtu)
1072 		dst->ops->update_pmtu(dst, NULL, skb, dst->dev->mtu, false);
1073 
1074 	err = ip6_tnl_xmit(skb, dev, dsfield, &fl6, encap_limit, &mtu,
1075 			   NEXTHDR_GRE);
1076 	if (err != 0) {
1077 		/* XXX: send ICMP error even if DF is not set. */
1078 		if (err == -EMSGSIZE) {
1079 			if (skb->protocol == htons(ETH_P_IP))
1080 				icmp_ndo_send(skb, ICMP_DEST_UNREACH,
1081 					      ICMP_FRAG_NEEDED, htonl(mtu));
1082 			else
1083 				icmpv6_ndo_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
1084 		}
1085 
1086 		goto tx_err;
1087 	}
1088 	return NETDEV_TX_OK;
1089 
1090 tx_err:
1091 	if (!IS_ERR(tun_info))
1092 		DEV_STATS_INC(dev, tx_errors);
1093 	DEV_STATS_INC(dev, tx_dropped);
1094 	kfree_skb(skb);
1095 	return NETDEV_TX_OK;
1096 }
1097 
1098 static void ip6gre_tnl_link_config_common(struct ip6_tnl *t)
1099 {
1100 	struct net_device *dev = t->dev;
1101 	struct __ip6_tnl_parm *p = &t->parms;
1102 	struct flowi6 *fl6 = &t->fl.u.ip6;
1103 
1104 	if (dev->type != ARPHRD_ETHER) {
1105 		__dev_addr_set(dev, &p->laddr, sizeof(struct in6_addr));
1106 		memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr));
1107 	}
1108 
1109 	/* Set up flowi template */
1110 	fl6->saddr = p->laddr;
1111 	fl6->daddr = p->raddr;
1112 	fl6->flowi6_oif = p->link;
1113 	fl6->flowlabel = 0;
1114 	fl6->flowi6_proto = IPPROTO_GRE;
1115 	fl6->fl6_gre_key = t->parms.o_key;
1116 
1117 	if (!(p->flags&IP6_TNL_F_USE_ORIG_TCLASS))
1118 		fl6->flowlabel |= IPV6_TCLASS_MASK & p->flowinfo;
1119 	if (!(p->flags&IP6_TNL_F_USE_ORIG_FLOWLABEL))
1120 		fl6->flowlabel |= IPV6_FLOWLABEL_MASK & p->flowinfo;
1121 
1122 	p->flags &= ~(IP6_TNL_F_CAP_XMIT|IP6_TNL_F_CAP_RCV|IP6_TNL_F_CAP_PER_PACKET);
1123 	p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr);
1124 
1125 	if (p->flags&IP6_TNL_F_CAP_XMIT &&
1126 			p->flags&IP6_TNL_F_CAP_RCV && dev->type != ARPHRD_ETHER)
1127 		dev->flags |= IFF_POINTOPOINT;
1128 	else
1129 		dev->flags &= ~IFF_POINTOPOINT;
1130 }
1131 
1132 static void ip6gre_tnl_link_config_route(struct ip6_tnl *t, int set_mtu,
1133 					 int t_hlen)
1134 {
1135 	const struct __ip6_tnl_parm *p = &t->parms;
1136 	struct net_device *dev = t->dev;
1137 
1138 	if (p->flags & IP6_TNL_F_CAP_XMIT) {
1139 		int strict = (ipv6_addr_type(&p->raddr) &
1140 			      (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL));
1141 
1142 		struct rt6_info *rt = rt6_lookup(t->net,
1143 						 &p->raddr, &p->laddr,
1144 						 p->link, NULL, strict);
1145 
1146 		if (!rt)
1147 			return;
1148 
1149 		if (rt->dst.dev) {
1150 			unsigned short dst_len = rt->dst.dev->hard_header_len +
1151 						 t_hlen;
1152 
1153 			if (t->dev->header_ops)
1154 				dev->hard_header_len = dst_len;
1155 			else
1156 				dev->needed_headroom = dst_len;
1157 
1158 			if (set_mtu) {
1159 				int mtu = rt->dst.dev->mtu - t_hlen;
1160 
1161 				if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1162 					mtu -= 8;
1163 				if (dev->type == ARPHRD_ETHER)
1164 					mtu -= ETH_HLEN;
1165 
1166 				if (mtu < IPV6_MIN_MTU)
1167 					mtu = IPV6_MIN_MTU;
1168 				WRITE_ONCE(dev->mtu, mtu);
1169 			}
1170 		}
1171 		ip6_rt_put(rt);
1172 	}
1173 }
1174 
1175 static int ip6gre_calc_hlen(struct ip6_tnl *tunnel)
1176 {
1177 	int t_hlen;
1178 
1179 	tunnel->tun_hlen = gre_calc_hlen(tunnel->parms.o_flags);
1180 	tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen;
1181 
1182 	t_hlen = tunnel->hlen + sizeof(struct ipv6hdr);
1183 
1184 	if (tunnel->dev->header_ops)
1185 		tunnel->dev->hard_header_len = LL_MAX_HEADER + t_hlen;
1186 	else
1187 		tunnel->dev->needed_headroom = LL_MAX_HEADER + t_hlen;
1188 
1189 	return t_hlen;
1190 }
1191 
1192 static void ip6gre_tnl_link_config(struct ip6_tnl *t, int set_mtu)
1193 {
1194 	ip6gre_tnl_link_config_common(t);
1195 	ip6gre_tnl_link_config_route(t, set_mtu, ip6gre_calc_hlen(t));
1196 }
1197 
1198 static void ip6gre_tnl_copy_tnl_parm(struct ip6_tnl *t,
1199 				     const struct __ip6_tnl_parm *p)
1200 {
1201 	t->parms.laddr = p->laddr;
1202 	t->parms.raddr = p->raddr;
1203 	t->parms.flags = p->flags;
1204 	t->parms.hop_limit = p->hop_limit;
1205 	t->parms.encap_limit = p->encap_limit;
1206 	t->parms.flowinfo = p->flowinfo;
1207 	t->parms.link = p->link;
1208 	t->parms.proto = p->proto;
1209 	t->parms.i_key = p->i_key;
1210 	t->parms.o_key = p->o_key;
1211 	t->parms.i_flags = p->i_flags;
1212 	t->parms.o_flags = p->o_flags;
1213 	t->parms.fwmark = p->fwmark;
1214 	t->parms.erspan_ver = p->erspan_ver;
1215 	t->parms.index = p->index;
1216 	t->parms.dir = p->dir;
1217 	t->parms.hwid = p->hwid;
1218 	dst_cache_reset(&t->dst_cache);
1219 }
1220 
1221 static int ip6gre_tnl_change(struct ip6_tnl *t, const struct __ip6_tnl_parm *p,
1222 			     int set_mtu)
1223 {
1224 	ip6gre_tnl_copy_tnl_parm(t, p);
1225 	ip6gre_tnl_link_config(t, set_mtu);
1226 	return 0;
1227 }
1228 
1229 static void ip6gre_tnl_parm_from_user(struct __ip6_tnl_parm *p,
1230 	const struct ip6_tnl_parm2 *u)
1231 {
1232 	p->laddr = u->laddr;
1233 	p->raddr = u->raddr;
1234 	p->flags = u->flags;
1235 	p->hop_limit = u->hop_limit;
1236 	p->encap_limit = u->encap_limit;
1237 	p->flowinfo = u->flowinfo;
1238 	p->link = u->link;
1239 	p->i_key = u->i_key;
1240 	p->o_key = u->o_key;
1241 	p->i_flags = gre_flags_to_tnl_flags(u->i_flags);
1242 	p->o_flags = gre_flags_to_tnl_flags(u->o_flags);
1243 	memcpy(p->name, u->name, sizeof(u->name));
1244 }
1245 
1246 static void ip6gre_tnl_parm_to_user(struct ip6_tnl_parm2 *u,
1247 	const struct __ip6_tnl_parm *p)
1248 {
1249 	u->proto = IPPROTO_GRE;
1250 	u->laddr = p->laddr;
1251 	u->raddr = p->raddr;
1252 	u->flags = p->flags;
1253 	u->hop_limit = p->hop_limit;
1254 	u->encap_limit = p->encap_limit;
1255 	u->flowinfo = p->flowinfo;
1256 	u->link = p->link;
1257 	u->i_key = p->i_key;
1258 	u->o_key = p->o_key;
1259 	u->i_flags = gre_tnl_flags_to_gre_flags(p->i_flags);
1260 	u->o_flags = gre_tnl_flags_to_gre_flags(p->o_flags);
1261 	memcpy(u->name, p->name, sizeof(u->name));
1262 }
1263 
1264 static int ip6gre_tunnel_siocdevprivate(struct net_device *dev,
1265 					struct ifreq *ifr, void __user *data,
1266 					int cmd)
1267 {
1268 	int err = 0;
1269 	struct ip6_tnl_parm2 p;
1270 	struct __ip6_tnl_parm p1;
1271 	struct ip6_tnl *t = netdev_priv(dev);
1272 	struct net *net = t->net;
1273 	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
1274 
1275 	memset(&p1, 0, sizeof(p1));
1276 
1277 	switch (cmd) {
1278 	case SIOCGETTUNNEL:
1279 		if (dev == ign->fb_tunnel_dev) {
1280 			if (copy_from_user(&p, data, sizeof(p))) {
1281 				err = -EFAULT;
1282 				break;
1283 			}
1284 			ip6gre_tnl_parm_from_user(&p1, &p);
1285 			t = ip6gre_tunnel_locate(net, &p1, 0);
1286 			if (!t)
1287 				t = netdev_priv(dev);
1288 		}
1289 		memset(&p, 0, sizeof(p));
1290 		ip6gre_tnl_parm_to_user(&p, &t->parms);
1291 		if (copy_to_user(data, &p, sizeof(p)))
1292 			err = -EFAULT;
1293 		break;
1294 
1295 	case SIOCADDTUNNEL:
1296 	case SIOCCHGTUNNEL:
1297 		err = -EPERM;
1298 		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1299 			goto done;
1300 
1301 		err = -EFAULT;
1302 		if (copy_from_user(&p, data, sizeof(p)))
1303 			goto done;
1304 
1305 		err = -EINVAL;
1306 		if ((p.i_flags|p.o_flags)&(GRE_VERSION|GRE_ROUTING))
1307 			goto done;
1308 
1309 		if (!(p.i_flags&GRE_KEY))
1310 			p.i_key = 0;
1311 		if (!(p.o_flags&GRE_KEY))
1312 			p.o_key = 0;
1313 
1314 		ip6gre_tnl_parm_from_user(&p1, &p);
1315 		t = ip6gre_tunnel_locate(net, &p1, cmd == SIOCADDTUNNEL);
1316 
1317 		if (dev != ign->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) {
1318 			if (t) {
1319 				if (t->dev != dev) {
1320 					err = -EEXIST;
1321 					break;
1322 				}
1323 			} else {
1324 				t = netdev_priv(dev);
1325 
1326 				ip6gre_tunnel_unlink(ign, t);
1327 				synchronize_net();
1328 				ip6gre_tnl_change(t, &p1, 1);
1329 				ip6gre_tunnel_link(ign, t);
1330 				netdev_state_change(dev);
1331 			}
1332 		}
1333 
1334 		if (t) {
1335 			err = 0;
1336 
1337 			memset(&p, 0, sizeof(p));
1338 			ip6gre_tnl_parm_to_user(&p, &t->parms);
1339 			if (copy_to_user(data, &p, sizeof(p)))
1340 				err = -EFAULT;
1341 		} else
1342 			err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
1343 		break;
1344 
1345 	case SIOCDELTUNNEL:
1346 		err = -EPERM;
1347 		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1348 			goto done;
1349 
1350 		if (dev == ign->fb_tunnel_dev) {
1351 			err = -EFAULT;
1352 			if (copy_from_user(&p, data, sizeof(p)))
1353 				goto done;
1354 			err = -ENOENT;
1355 			ip6gre_tnl_parm_from_user(&p1, &p);
1356 			t = ip6gre_tunnel_locate(net, &p1, 0);
1357 			if (!t)
1358 				goto done;
1359 			err = -EPERM;
1360 			if (t == netdev_priv(ign->fb_tunnel_dev))
1361 				goto done;
1362 			dev = t->dev;
1363 		}
1364 		unregister_netdevice(dev);
1365 		err = 0;
1366 		break;
1367 
1368 	default:
1369 		err = -EINVAL;
1370 	}
1371 
1372 done:
1373 	return err;
1374 }
1375 
1376 static int ip6gre_header(struct sk_buff *skb, struct net_device *dev,
1377 			 unsigned short type, const void *daddr,
1378 			 const void *saddr, unsigned int len)
1379 {
1380 	struct ip6_tnl *t = netdev_priv(dev);
1381 	struct ipv6hdr *ipv6h;
1382 	__be16 *p;
1383 
1384 	ipv6h = skb_push(skb, t->hlen + sizeof(*ipv6h));
1385 	ip6_flow_hdr(ipv6h, 0, ip6_make_flowlabel(dev_net(dev), skb,
1386 						  t->fl.u.ip6.flowlabel,
1387 						  true, &t->fl.u.ip6));
1388 	ipv6h->hop_limit = t->parms.hop_limit;
1389 	ipv6h->nexthdr = NEXTHDR_GRE;
1390 	ipv6h->saddr = t->parms.laddr;
1391 	ipv6h->daddr = t->parms.raddr;
1392 
1393 	p = (__be16 *)(ipv6h + 1);
1394 	p[0] = t->parms.o_flags;
1395 	p[1] = htons(type);
1396 
1397 	/*
1398 	 *	Set the source hardware address.
1399 	 */
1400 
1401 	if (saddr)
1402 		memcpy(&ipv6h->saddr, saddr, sizeof(struct in6_addr));
1403 	if (daddr)
1404 		memcpy(&ipv6h->daddr, daddr, sizeof(struct in6_addr));
1405 	if (!ipv6_addr_any(&ipv6h->daddr))
1406 		return t->hlen;
1407 
1408 	return -t->hlen;
1409 }
1410 
1411 static const struct header_ops ip6gre_header_ops = {
1412 	.create	= ip6gre_header,
1413 };
1414 
1415 static const struct net_device_ops ip6gre_netdev_ops = {
1416 	.ndo_init		= ip6gre_tunnel_init,
1417 	.ndo_uninit		= ip6gre_tunnel_uninit,
1418 	.ndo_start_xmit		= ip6gre_tunnel_xmit,
1419 	.ndo_siocdevprivate	= ip6gre_tunnel_siocdevprivate,
1420 	.ndo_change_mtu		= ip6_tnl_change_mtu,
1421 	.ndo_get_stats64	= dev_get_tstats64,
1422 	.ndo_get_iflink		= ip6_tnl_get_iflink,
1423 };
1424 
1425 static void ip6gre_dev_free(struct net_device *dev)
1426 {
1427 	struct ip6_tnl *t = netdev_priv(dev);
1428 
1429 	gro_cells_destroy(&t->gro_cells);
1430 	dst_cache_destroy(&t->dst_cache);
1431 	free_percpu(dev->tstats);
1432 }
1433 
1434 static void ip6gre_tunnel_setup(struct net_device *dev)
1435 {
1436 	dev->netdev_ops = &ip6gre_netdev_ops;
1437 	dev->needs_free_netdev = true;
1438 	dev->priv_destructor = ip6gre_dev_free;
1439 
1440 	dev->type = ARPHRD_IP6GRE;
1441 
1442 	dev->flags |= IFF_NOARP;
1443 	dev->addr_len = sizeof(struct in6_addr);
1444 	netif_keep_dst(dev);
1445 	/* This perm addr will be used as interface identifier by IPv6 */
1446 	dev->addr_assign_type = NET_ADDR_RANDOM;
1447 	eth_random_addr(dev->perm_addr);
1448 }
1449 
1450 #define GRE6_FEATURES (NETIF_F_SG |		\
1451 		       NETIF_F_FRAGLIST |	\
1452 		       NETIF_F_HIGHDMA |	\
1453 		       NETIF_F_HW_CSUM)
1454 
1455 static void ip6gre_tnl_init_features(struct net_device *dev)
1456 {
1457 	struct ip6_tnl *nt = netdev_priv(dev);
1458 	__be16 flags;
1459 
1460 	dev->features		|= GRE6_FEATURES | NETIF_F_LLTX;
1461 	dev->hw_features	|= GRE6_FEATURES;
1462 
1463 	flags = nt->parms.o_flags;
1464 
1465 	/* TCP offload with GRE SEQ is not supported, nor can we support 2
1466 	 * levels of outer headers requiring an update.
1467 	 */
1468 	if (flags & TUNNEL_SEQ)
1469 		return;
1470 	if (flags & TUNNEL_CSUM && nt->encap.type != TUNNEL_ENCAP_NONE)
1471 		return;
1472 
1473 	dev->features |= NETIF_F_GSO_SOFTWARE;
1474 	dev->hw_features |= NETIF_F_GSO_SOFTWARE;
1475 }
1476 
1477 static int ip6gre_tunnel_init_common(struct net_device *dev)
1478 {
1479 	struct ip6_tnl *tunnel;
1480 	int ret;
1481 	int t_hlen;
1482 
1483 	tunnel = netdev_priv(dev);
1484 
1485 	tunnel->dev = dev;
1486 	tunnel->net = dev_net(dev);
1487 	strcpy(tunnel->parms.name, dev->name);
1488 
1489 	dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
1490 	if (!dev->tstats)
1491 		return -ENOMEM;
1492 
1493 	ret = dst_cache_init(&tunnel->dst_cache, GFP_KERNEL);
1494 	if (ret)
1495 		goto cleanup_alloc_pcpu_stats;
1496 
1497 	ret = gro_cells_init(&tunnel->gro_cells, dev);
1498 	if (ret)
1499 		goto cleanup_dst_cache_init;
1500 
1501 	t_hlen = ip6gre_calc_hlen(tunnel);
1502 	dev->mtu = ETH_DATA_LEN - t_hlen;
1503 	if (dev->type == ARPHRD_ETHER)
1504 		dev->mtu -= ETH_HLEN;
1505 	if (!(tunnel->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1506 		dev->mtu -= 8;
1507 
1508 	if (tunnel->parms.collect_md) {
1509 		netif_keep_dst(dev);
1510 	}
1511 	ip6gre_tnl_init_features(dev);
1512 
1513 	netdev_hold(dev, &tunnel->dev_tracker, GFP_KERNEL);
1514 	return 0;
1515 
1516 cleanup_dst_cache_init:
1517 	dst_cache_destroy(&tunnel->dst_cache);
1518 cleanup_alloc_pcpu_stats:
1519 	free_percpu(dev->tstats);
1520 	dev->tstats = NULL;
1521 	return ret;
1522 }
1523 
1524 static int ip6gre_tunnel_init(struct net_device *dev)
1525 {
1526 	struct ip6_tnl *tunnel;
1527 	int ret;
1528 
1529 	ret = ip6gre_tunnel_init_common(dev);
1530 	if (ret)
1531 		return ret;
1532 
1533 	tunnel = netdev_priv(dev);
1534 
1535 	if (tunnel->parms.collect_md)
1536 		return 0;
1537 
1538 	__dev_addr_set(dev, &tunnel->parms.laddr, sizeof(struct in6_addr));
1539 	memcpy(dev->broadcast, &tunnel->parms.raddr, sizeof(struct in6_addr));
1540 
1541 	if (ipv6_addr_any(&tunnel->parms.raddr))
1542 		dev->header_ops = &ip6gre_header_ops;
1543 
1544 	return 0;
1545 }
1546 
1547 static void ip6gre_fb_tunnel_init(struct net_device *dev)
1548 {
1549 	struct ip6_tnl *tunnel = netdev_priv(dev);
1550 
1551 	tunnel->dev = dev;
1552 	tunnel->net = dev_net(dev);
1553 	strcpy(tunnel->parms.name, dev->name);
1554 
1555 	tunnel->hlen		= sizeof(struct ipv6hdr) + 4;
1556 }
1557 
1558 static struct inet6_protocol ip6gre_protocol __read_mostly = {
1559 	.handler     = gre_rcv,
1560 	.err_handler = ip6gre_err,
1561 	.flags       = INET6_PROTO_FINAL,
1562 };
1563 
1564 static void ip6gre_destroy_tunnels(struct net *net, struct list_head *head)
1565 {
1566 	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
1567 	struct net_device *dev, *aux;
1568 	int prio;
1569 
1570 	for_each_netdev_safe(net, dev, aux)
1571 		if (dev->rtnl_link_ops == &ip6gre_link_ops ||
1572 		    dev->rtnl_link_ops == &ip6gre_tap_ops ||
1573 		    dev->rtnl_link_ops == &ip6erspan_tap_ops)
1574 			unregister_netdevice_queue(dev, head);
1575 
1576 	for (prio = 0; prio < 4; prio++) {
1577 		int h;
1578 		for (h = 0; h < IP6_GRE_HASH_SIZE; h++) {
1579 			struct ip6_tnl *t;
1580 
1581 			t = rtnl_dereference(ign->tunnels[prio][h]);
1582 
1583 			while (t) {
1584 				/* If dev is in the same netns, it has already
1585 				 * been added to the list by the previous loop.
1586 				 */
1587 				if (!net_eq(dev_net(t->dev), net))
1588 					unregister_netdevice_queue(t->dev,
1589 								   head);
1590 				t = rtnl_dereference(t->next);
1591 			}
1592 		}
1593 	}
1594 }
1595 
1596 static int __net_init ip6gre_init_net(struct net *net)
1597 {
1598 	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
1599 	struct net_device *ndev;
1600 	int err;
1601 
1602 	if (!net_has_fallback_tunnels(net))
1603 		return 0;
1604 	ndev = alloc_netdev(sizeof(struct ip6_tnl), "ip6gre0",
1605 			    NET_NAME_UNKNOWN, ip6gre_tunnel_setup);
1606 	if (!ndev) {
1607 		err = -ENOMEM;
1608 		goto err_alloc_dev;
1609 	}
1610 	ign->fb_tunnel_dev = ndev;
1611 	dev_net_set(ign->fb_tunnel_dev, net);
1612 	/* FB netdevice is special: we have one, and only one per netns.
1613 	 * Allowing to move it to another netns is clearly unsafe.
1614 	 */
1615 	ign->fb_tunnel_dev->features |= NETIF_F_NETNS_LOCAL;
1616 
1617 
1618 	ip6gre_fb_tunnel_init(ign->fb_tunnel_dev);
1619 	ign->fb_tunnel_dev->rtnl_link_ops = &ip6gre_link_ops;
1620 
1621 	err = register_netdev(ign->fb_tunnel_dev);
1622 	if (err)
1623 		goto err_reg_dev;
1624 
1625 	rcu_assign_pointer(ign->tunnels_wc[0],
1626 			   netdev_priv(ign->fb_tunnel_dev));
1627 	return 0;
1628 
1629 err_reg_dev:
1630 	free_netdev(ndev);
1631 err_alloc_dev:
1632 	return err;
1633 }
1634 
1635 static void __net_exit ip6gre_exit_batch_net(struct list_head *net_list)
1636 {
1637 	struct net *net;
1638 	LIST_HEAD(list);
1639 
1640 	rtnl_lock();
1641 	list_for_each_entry(net, net_list, exit_list)
1642 		ip6gre_destroy_tunnels(net, &list);
1643 	unregister_netdevice_many(&list);
1644 	rtnl_unlock();
1645 }
1646 
1647 static struct pernet_operations ip6gre_net_ops = {
1648 	.init = ip6gre_init_net,
1649 	.exit_batch = ip6gre_exit_batch_net,
1650 	.id   = &ip6gre_net_id,
1651 	.size = sizeof(struct ip6gre_net),
1652 };
1653 
1654 static int ip6gre_tunnel_validate(struct nlattr *tb[], struct nlattr *data[],
1655 				  struct netlink_ext_ack *extack)
1656 {
1657 	__be16 flags;
1658 
1659 	if (!data)
1660 		return 0;
1661 
1662 	flags = 0;
1663 	if (data[IFLA_GRE_IFLAGS])
1664 		flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]);
1665 	if (data[IFLA_GRE_OFLAGS])
1666 		flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]);
1667 	if (flags & (GRE_VERSION|GRE_ROUTING))
1668 		return -EINVAL;
1669 
1670 	return 0;
1671 }
1672 
1673 static int ip6gre_tap_validate(struct nlattr *tb[], struct nlattr *data[],
1674 			       struct netlink_ext_ack *extack)
1675 {
1676 	struct in6_addr daddr;
1677 
1678 	if (tb[IFLA_ADDRESS]) {
1679 		if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
1680 			return -EINVAL;
1681 		if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
1682 			return -EADDRNOTAVAIL;
1683 	}
1684 
1685 	if (!data)
1686 		goto out;
1687 
1688 	if (data[IFLA_GRE_REMOTE]) {
1689 		daddr = nla_get_in6_addr(data[IFLA_GRE_REMOTE]);
1690 		if (ipv6_addr_any(&daddr))
1691 			return -EINVAL;
1692 	}
1693 
1694 out:
1695 	return ip6gre_tunnel_validate(tb, data, extack);
1696 }
1697 
1698 static int ip6erspan_tap_validate(struct nlattr *tb[], struct nlattr *data[],
1699 				  struct netlink_ext_ack *extack)
1700 {
1701 	__be16 flags = 0;
1702 	int ret, ver = 0;
1703 
1704 	if (!data)
1705 		return 0;
1706 
1707 	ret = ip6gre_tap_validate(tb, data, extack);
1708 	if (ret)
1709 		return ret;
1710 
1711 	/* ERSPAN should only have GRE sequence and key flag */
1712 	if (data[IFLA_GRE_OFLAGS])
1713 		flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]);
1714 	if (data[IFLA_GRE_IFLAGS])
1715 		flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]);
1716 	if (!data[IFLA_GRE_COLLECT_METADATA] &&
1717 	    flags != (GRE_SEQ | GRE_KEY))
1718 		return -EINVAL;
1719 
1720 	/* ERSPAN Session ID only has 10-bit. Since we reuse
1721 	 * 32-bit key field as ID, check it's range.
1722 	 */
1723 	if (data[IFLA_GRE_IKEY] &&
1724 	    (ntohl(nla_get_be32(data[IFLA_GRE_IKEY])) & ~ID_MASK))
1725 		return -EINVAL;
1726 
1727 	if (data[IFLA_GRE_OKEY] &&
1728 	    (ntohl(nla_get_be32(data[IFLA_GRE_OKEY])) & ~ID_MASK))
1729 		return -EINVAL;
1730 
1731 	if (data[IFLA_GRE_ERSPAN_VER]) {
1732 		ver = nla_get_u8(data[IFLA_GRE_ERSPAN_VER]);
1733 		if (ver != 1 && ver != 2)
1734 			return -EINVAL;
1735 	}
1736 
1737 	if (ver == 1) {
1738 		if (data[IFLA_GRE_ERSPAN_INDEX]) {
1739 			u32 index = nla_get_u32(data[IFLA_GRE_ERSPAN_INDEX]);
1740 
1741 			if (index & ~INDEX_MASK)
1742 				return -EINVAL;
1743 		}
1744 	} else if (ver == 2) {
1745 		if (data[IFLA_GRE_ERSPAN_DIR]) {
1746 			u16 dir = nla_get_u8(data[IFLA_GRE_ERSPAN_DIR]);
1747 
1748 			if (dir & ~(DIR_MASK >> DIR_OFFSET))
1749 				return -EINVAL;
1750 		}
1751 
1752 		if (data[IFLA_GRE_ERSPAN_HWID]) {
1753 			u16 hwid = nla_get_u16(data[IFLA_GRE_ERSPAN_HWID]);
1754 
1755 			if (hwid & ~(HWID_MASK >> HWID_OFFSET))
1756 				return -EINVAL;
1757 		}
1758 	}
1759 
1760 	return 0;
1761 }
1762 
1763 static void ip6erspan_set_version(struct nlattr *data[],
1764 				  struct __ip6_tnl_parm *parms)
1765 {
1766 	if (!data)
1767 		return;
1768 
1769 	parms->erspan_ver = 1;
1770 	if (data[IFLA_GRE_ERSPAN_VER])
1771 		parms->erspan_ver = nla_get_u8(data[IFLA_GRE_ERSPAN_VER]);
1772 
1773 	if (parms->erspan_ver == 1) {
1774 		if (data[IFLA_GRE_ERSPAN_INDEX])
1775 			parms->index = nla_get_u32(data[IFLA_GRE_ERSPAN_INDEX]);
1776 	} else if (parms->erspan_ver == 2) {
1777 		if (data[IFLA_GRE_ERSPAN_DIR])
1778 			parms->dir = nla_get_u8(data[IFLA_GRE_ERSPAN_DIR]);
1779 		if (data[IFLA_GRE_ERSPAN_HWID])
1780 			parms->hwid = nla_get_u16(data[IFLA_GRE_ERSPAN_HWID]);
1781 	}
1782 }
1783 
1784 static void ip6gre_netlink_parms(struct nlattr *data[],
1785 				struct __ip6_tnl_parm *parms)
1786 {
1787 	memset(parms, 0, sizeof(*parms));
1788 
1789 	if (!data)
1790 		return;
1791 
1792 	if (data[IFLA_GRE_LINK])
1793 		parms->link = nla_get_u32(data[IFLA_GRE_LINK]);
1794 
1795 	if (data[IFLA_GRE_IFLAGS])
1796 		parms->i_flags = gre_flags_to_tnl_flags(
1797 				nla_get_be16(data[IFLA_GRE_IFLAGS]));
1798 
1799 	if (data[IFLA_GRE_OFLAGS])
1800 		parms->o_flags = gre_flags_to_tnl_flags(
1801 				nla_get_be16(data[IFLA_GRE_OFLAGS]));
1802 
1803 	if (data[IFLA_GRE_IKEY])
1804 		parms->i_key = nla_get_be32(data[IFLA_GRE_IKEY]);
1805 
1806 	if (data[IFLA_GRE_OKEY])
1807 		parms->o_key = nla_get_be32(data[IFLA_GRE_OKEY]);
1808 
1809 	if (data[IFLA_GRE_LOCAL])
1810 		parms->laddr = nla_get_in6_addr(data[IFLA_GRE_LOCAL]);
1811 
1812 	if (data[IFLA_GRE_REMOTE])
1813 		parms->raddr = nla_get_in6_addr(data[IFLA_GRE_REMOTE]);
1814 
1815 	if (data[IFLA_GRE_TTL])
1816 		parms->hop_limit = nla_get_u8(data[IFLA_GRE_TTL]);
1817 
1818 	if (data[IFLA_GRE_ENCAP_LIMIT])
1819 		parms->encap_limit = nla_get_u8(data[IFLA_GRE_ENCAP_LIMIT]);
1820 
1821 	if (data[IFLA_GRE_FLOWINFO])
1822 		parms->flowinfo = nla_get_be32(data[IFLA_GRE_FLOWINFO]);
1823 
1824 	if (data[IFLA_GRE_FLAGS])
1825 		parms->flags = nla_get_u32(data[IFLA_GRE_FLAGS]);
1826 
1827 	if (data[IFLA_GRE_FWMARK])
1828 		parms->fwmark = nla_get_u32(data[IFLA_GRE_FWMARK]);
1829 
1830 	if (data[IFLA_GRE_COLLECT_METADATA])
1831 		parms->collect_md = true;
1832 }
1833 
1834 static int ip6gre_tap_init(struct net_device *dev)
1835 {
1836 	int ret;
1837 
1838 	ret = ip6gre_tunnel_init_common(dev);
1839 	if (ret)
1840 		return ret;
1841 
1842 	dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1843 
1844 	return 0;
1845 }
1846 
1847 static const struct net_device_ops ip6gre_tap_netdev_ops = {
1848 	.ndo_init = ip6gre_tap_init,
1849 	.ndo_uninit = ip6gre_tunnel_uninit,
1850 	.ndo_start_xmit = ip6gre_tunnel_xmit,
1851 	.ndo_set_mac_address = eth_mac_addr,
1852 	.ndo_validate_addr = eth_validate_addr,
1853 	.ndo_change_mtu = ip6_tnl_change_mtu,
1854 	.ndo_get_stats64 = dev_get_tstats64,
1855 	.ndo_get_iflink = ip6_tnl_get_iflink,
1856 };
1857 
1858 static int ip6erspan_calc_hlen(struct ip6_tnl *tunnel)
1859 {
1860 	int t_hlen;
1861 
1862 	tunnel->tun_hlen = 8;
1863 	tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen +
1864 		       erspan_hdr_len(tunnel->parms.erspan_ver);
1865 
1866 	t_hlen = tunnel->hlen + sizeof(struct ipv6hdr);
1867 	tunnel->dev->needed_headroom = LL_MAX_HEADER + t_hlen;
1868 	return t_hlen;
1869 }
1870 
1871 static int ip6erspan_tap_init(struct net_device *dev)
1872 {
1873 	struct ip6_tnl *tunnel;
1874 	int t_hlen;
1875 	int ret;
1876 
1877 	tunnel = netdev_priv(dev);
1878 
1879 	tunnel->dev = dev;
1880 	tunnel->net = dev_net(dev);
1881 	strcpy(tunnel->parms.name, dev->name);
1882 
1883 	dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
1884 	if (!dev->tstats)
1885 		return -ENOMEM;
1886 
1887 	ret = dst_cache_init(&tunnel->dst_cache, GFP_KERNEL);
1888 	if (ret)
1889 		goto cleanup_alloc_pcpu_stats;
1890 
1891 	ret = gro_cells_init(&tunnel->gro_cells, dev);
1892 	if (ret)
1893 		goto cleanup_dst_cache_init;
1894 
1895 	t_hlen = ip6erspan_calc_hlen(tunnel);
1896 	dev->mtu = ETH_DATA_LEN - t_hlen;
1897 	if (dev->type == ARPHRD_ETHER)
1898 		dev->mtu -= ETH_HLEN;
1899 	if (!(tunnel->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1900 		dev->mtu -= 8;
1901 
1902 	dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1903 	ip6erspan_tnl_link_config(tunnel, 1);
1904 
1905 	netdev_hold(dev, &tunnel->dev_tracker, GFP_KERNEL);
1906 	return 0;
1907 
1908 cleanup_dst_cache_init:
1909 	dst_cache_destroy(&tunnel->dst_cache);
1910 cleanup_alloc_pcpu_stats:
1911 	free_percpu(dev->tstats);
1912 	dev->tstats = NULL;
1913 	return ret;
1914 }
1915 
1916 static const struct net_device_ops ip6erspan_netdev_ops = {
1917 	.ndo_init =		ip6erspan_tap_init,
1918 	.ndo_uninit =		ip6erspan_tunnel_uninit,
1919 	.ndo_start_xmit =	ip6erspan_tunnel_xmit,
1920 	.ndo_set_mac_address =	eth_mac_addr,
1921 	.ndo_validate_addr =	eth_validate_addr,
1922 	.ndo_change_mtu =	ip6_tnl_change_mtu,
1923 	.ndo_get_stats64 =	dev_get_tstats64,
1924 	.ndo_get_iflink =	ip6_tnl_get_iflink,
1925 };
1926 
1927 static void ip6gre_tap_setup(struct net_device *dev)
1928 {
1929 
1930 	ether_setup(dev);
1931 
1932 	dev->max_mtu = 0;
1933 	dev->netdev_ops = &ip6gre_tap_netdev_ops;
1934 	dev->needs_free_netdev = true;
1935 	dev->priv_destructor = ip6gre_dev_free;
1936 
1937 	dev->priv_flags &= ~IFF_TX_SKB_SHARING;
1938 	dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1939 	netif_keep_dst(dev);
1940 }
1941 
1942 static bool ip6gre_netlink_encap_parms(struct nlattr *data[],
1943 				       struct ip_tunnel_encap *ipencap)
1944 {
1945 	bool ret = false;
1946 
1947 	memset(ipencap, 0, sizeof(*ipencap));
1948 
1949 	if (!data)
1950 		return ret;
1951 
1952 	if (data[IFLA_GRE_ENCAP_TYPE]) {
1953 		ret = true;
1954 		ipencap->type = nla_get_u16(data[IFLA_GRE_ENCAP_TYPE]);
1955 	}
1956 
1957 	if (data[IFLA_GRE_ENCAP_FLAGS]) {
1958 		ret = true;
1959 		ipencap->flags = nla_get_u16(data[IFLA_GRE_ENCAP_FLAGS]);
1960 	}
1961 
1962 	if (data[IFLA_GRE_ENCAP_SPORT]) {
1963 		ret = true;
1964 		ipencap->sport = nla_get_be16(data[IFLA_GRE_ENCAP_SPORT]);
1965 	}
1966 
1967 	if (data[IFLA_GRE_ENCAP_DPORT]) {
1968 		ret = true;
1969 		ipencap->dport = nla_get_be16(data[IFLA_GRE_ENCAP_DPORT]);
1970 	}
1971 
1972 	return ret;
1973 }
1974 
1975 static int ip6gre_newlink_common(struct net *src_net, struct net_device *dev,
1976 				 struct nlattr *tb[], struct nlattr *data[],
1977 				 struct netlink_ext_ack *extack)
1978 {
1979 	struct ip6_tnl *nt;
1980 	struct ip_tunnel_encap ipencap;
1981 	int err;
1982 
1983 	nt = netdev_priv(dev);
1984 
1985 	if (ip6gre_netlink_encap_parms(data, &ipencap)) {
1986 		int err = ip6_tnl_encap_setup(nt, &ipencap);
1987 
1988 		if (err < 0)
1989 			return err;
1990 	}
1991 
1992 	if (dev->type == ARPHRD_ETHER && !tb[IFLA_ADDRESS])
1993 		eth_hw_addr_random(dev);
1994 
1995 	nt->dev = dev;
1996 	nt->net = dev_net(dev);
1997 
1998 	err = register_netdevice(dev);
1999 	if (err)
2000 		goto out;
2001 
2002 	if (tb[IFLA_MTU])
2003 		ip6_tnl_change_mtu(dev, nla_get_u32(tb[IFLA_MTU]));
2004 
2005 out:
2006 	return err;
2007 }
2008 
2009 static int ip6gre_newlink(struct net *src_net, struct net_device *dev,
2010 			  struct nlattr *tb[], struct nlattr *data[],
2011 			  struct netlink_ext_ack *extack)
2012 {
2013 	struct ip6_tnl *nt = netdev_priv(dev);
2014 	struct net *net = dev_net(dev);
2015 	struct ip6gre_net *ign;
2016 	int err;
2017 
2018 	ip6gre_netlink_parms(data, &nt->parms);
2019 	ign = net_generic(net, ip6gre_net_id);
2020 
2021 	if (nt->parms.collect_md) {
2022 		if (rtnl_dereference(ign->collect_md_tun))
2023 			return -EEXIST;
2024 	} else {
2025 		if (ip6gre_tunnel_find(net, &nt->parms, dev->type))
2026 			return -EEXIST;
2027 	}
2028 
2029 	err = ip6gre_newlink_common(src_net, dev, tb, data, extack);
2030 	if (!err) {
2031 		ip6gre_tnl_link_config(nt, !tb[IFLA_MTU]);
2032 		ip6gre_tunnel_link_md(ign, nt);
2033 		ip6gre_tunnel_link(net_generic(net, ip6gre_net_id), nt);
2034 	}
2035 	return err;
2036 }
2037 
2038 static struct ip6_tnl *
2039 ip6gre_changelink_common(struct net_device *dev, struct nlattr *tb[],
2040 			 struct nlattr *data[], struct __ip6_tnl_parm *p_p,
2041 			 struct netlink_ext_ack *extack)
2042 {
2043 	struct ip6_tnl *t, *nt = netdev_priv(dev);
2044 	struct net *net = nt->net;
2045 	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
2046 	struct ip_tunnel_encap ipencap;
2047 
2048 	if (dev == ign->fb_tunnel_dev)
2049 		return ERR_PTR(-EINVAL);
2050 
2051 	if (ip6gre_netlink_encap_parms(data, &ipencap)) {
2052 		int err = ip6_tnl_encap_setup(nt, &ipencap);
2053 
2054 		if (err < 0)
2055 			return ERR_PTR(err);
2056 	}
2057 
2058 	ip6gre_netlink_parms(data, p_p);
2059 
2060 	t = ip6gre_tunnel_locate(net, p_p, 0);
2061 
2062 	if (t) {
2063 		if (t->dev != dev)
2064 			return ERR_PTR(-EEXIST);
2065 	} else {
2066 		t = nt;
2067 	}
2068 
2069 	return t;
2070 }
2071 
2072 static int ip6gre_changelink(struct net_device *dev, struct nlattr *tb[],
2073 			     struct nlattr *data[],
2074 			     struct netlink_ext_ack *extack)
2075 {
2076 	struct ip6_tnl *t = netdev_priv(dev);
2077 	struct ip6gre_net *ign = net_generic(t->net, ip6gre_net_id);
2078 	struct __ip6_tnl_parm p;
2079 
2080 	t = ip6gre_changelink_common(dev, tb, data, &p, extack);
2081 	if (IS_ERR(t))
2082 		return PTR_ERR(t);
2083 
2084 	ip6gre_tunnel_unlink_md(ign, t);
2085 	ip6gre_tunnel_unlink(ign, t);
2086 	ip6gre_tnl_change(t, &p, !tb[IFLA_MTU]);
2087 	ip6gre_tunnel_link_md(ign, t);
2088 	ip6gre_tunnel_link(ign, t);
2089 	return 0;
2090 }
2091 
2092 static void ip6gre_dellink(struct net_device *dev, struct list_head *head)
2093 {
2094 	struct net *net = dev_net(dev);
2095 	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
2096 
2097 	if (dev != ign->fb_tunnel_dev)
2098 		unregister_netdevice_queue(dev, head);
2099 }
2100 
2101 static size_t ip6gre_get_size(const struct net_device *dev)
2102 {
2103 	return
2104 		/* IFLA_GRE_LINK */
2105 		nla_total_size(4) +
2106 		/* IFLA_GRE_IFLAGS */
2107 		nla_total_size(2) +
2108 		/* IFLA_GRE_OFLAGS */
2109 		nla_total_size(2) +
2110 		/* IFLA_GRE_IKEY */
2111 		nla_total_size(4) +
2112 		/* IFLA_GRE_OKEY */
2113 		nla_total_size(4) +
2114 		/* IFLA_GRE_LOCAL */
2115 		nla_total_size(sizeof(struct in6_addr)) +
2116 		/* IFLA_GRE_REMOTE */
2117 		nla_total_size(sizeof(struct in6_addr)) +
2118 		/* IFLA_GRE_TTL */
2119 		nla_total_size(1) +
2120 		/* IFLA_GRE_ENCAP_LIMIT */
2121 		nla_total_size(1) +
2122 		/* IFLA_GRE_FLOWINFO */
2123 		nla_total_size(4) +
2124 		/* IFLA_GRE_FLAGS */
2125 		nla_total_size(4) +
2126 		/* IFLA_GRE_ENCAP_TYPE */
2127 		nla_total_size(2) +
2128 		/* IFLA_GRE_ENCAP_FLAGS */
2129 		nla_total_size(2) +
2130 		/* IFLA_GRE_ENCAP_SPORT */
2131 		nla_total_size(2) +
2132 		/* IFLA_GRE_ENCAP_DPORT */
2133 		nla_total_size(2) +
2134 		/* IFLA_GRE_COLLECT_METADATA */
2135 		nla_total_size(0) +
2136 		/* IFLA_GRE_FWMARK */
2137 		nla_total_size(4) +
2138 		/* IFLA_GRE_ERSPAN_INDEX */
2139 		nla_total_size(4) +
2140 		0;
2141 }
2142 
2143 static int ip6gre_fill_info(struct sk_buff *skb, const struct net_device *dev)
2144 {
2145 	struct ip6_tnl *t = netdev_priv(dev);
2146 	struct __ip6_tnl_parm *p = &t->parms;
2147 	__be16 o_flags = p->o_flags;
2148 
2149 	if (p->erspan_ver == 1 || p->erspan_ver == 2) {
2150 		if (!p->collect_md)
2151 			o_flags |= TUNNEL_KEY;
2152 
2153 		if (nla_put_u8(skb, IFLA_GRE_ERSPAN_VER, p->erspan_ver))
2154 			goto nla_put_failure;
2155 
2156 		if (p->erspan_ver == 1) {
2157 			if (nla_put_u32(skb, IFLA_GRE_ERSPAN_INDEX, p->index))
2158 				goto nla_put_failure;
2159 		} else {
2160 			if (nla_put_u8(skb, IFLA_GRE_ERSPAN_DIR, p->dir))
2161 				goto nla_put_failure;
2162 			if (nla_put_u16(skb, IFLA_GRE_ERSPAN_HWID, p->hwid))
2163 				goto nla_put_failure;
2164 		}
2165 	}
2166 
2167 	if (nla_put_u32(skb, IFLA_GRE_LINK, p->link) ||
2168 	    nla_put_be16(skb, IFLA_GRE_IFLAGS,
2169 			 gre_tnl_flags_to_gre_flags(p->i_flags)) ||
2170 	    nla_put_be16(skb, IFLA_GRE_OFLAGS,
2171 			 gre_tnl_flags_to_gre_flags(o_flags)) ||
2172 	    nla_put_be32(skb, IFLA_GRE_IKEY, p->i_key) ||
2173 	    nla_put_be32(skb, IFLA_GRE_OKEY, p->o_key) ||
2174 	    nla_put_in6_addr(skb, IFLA_GRE_LOCAL, &p->laddr) ||
2175 	    nla_put_in6_addr(skb, IFLA_GRE_REMOTE, &p->raddr) ||
2176 	    nla_put_u8(skb, IFLA_GRE_TTL, p->hop_limit) ||
2177 	    nla_put_u8(skb, IFLA_GRE_ENCAP_LIMIT, p->encap_limit) ||
2178 	    nla_put_be32(skb, IFLA_GRE_FLOWINFO, p->flowinfo) ||
2179 	    nla_put_u32(skb, IFLA_GRE_FLAGS, p->flags) ||
2180 	    nla_put_u32(skb, IFLA_GRE_FWMARK, p->fwmark))
2181 		goto nla_put_failure;
2182 
2183 	if (nla_put_u16(skb, IFLA_GRE_ENCAP_TYPE,
2184 			t->encap.type) ||
2185 	    nla_put_be16(skb, IFLA_GRE_ENCAP_SPORT,
2186 			 t->encap.sport) ||
2187 	    nla_put_be16(skb, IFLA_GRE_ENCAP_DPORT,
2188 			 t->encap.dport) ||
2189 	    nla_put_u16(skb, IFLA_GRE_ENCAP_FLAGS,
2190 			t->encap.flags))
2191 		goto nla_put_failure;
2192 
2193 	if (p->collect_md) {
2194 		if (nla_put_flag(skb, IFLA_GRE_COLLECT_METADATA))
2195 			goto nla_put_failure;
2196 	}
2197 
2198 	return 0;
2199 
2200 nla_put_failure:
2201 	return -EMSGSIZE;
2202 }
2203 
2204 static const struct nla_policy ip6gre_policy[IFLA_GRE_MAX + 1] = {
2205 	[IFLA_GRE_LINK]        = { .type = NLA_U32 },
2206 	[IFLA_GRE_IFLAGS]      = { .type = NLA_U16 },
2207 	[IFLA_GRE_OFLAGS]      = { .type = NLA_U16 },
2208 	[IFLA_GRE_IKEY]        = { .type = NLA_U32 },
2209 	[IFLA_GRE_OKEY]        = { .type = NLA_U32 },
2210 	[IFLA_GRE_LOCAL]       = { .len = sizeof_field(struct ipv6hdr, saddr) },
2211 	[IFLA_GRE_REMOTE]      = { .len = sizeof_field(struct ipv6hdr, daddr) },
2212 	[IFLA_GRE_TTL]         = { .type = NLA_U8 },
2213 	[IFLA_GRE_ENCAP_LIMIT] = { .type = NLA_U8 },
2214 	[IFLA_GRE_FLOWINFO]    = { .type = NLA_U32 },
2215 	[IFLA_GRE_FLAGS]       = { .type = NLA_U32 },
2216 	[IFLA_GRE_ENCAP_TYPE]   = { .type = NLA_U16 },
2217 	[IFLA_GRE_ENCAP_FLAGS]  = { .type = NLA_U16 },
2218 	[IFLA_GRE_ENCAP_SPORT]  = { .type = NLA_U16 },
2219 	[IFLA_GRE_ENCAP_DPORT]  = { .type = NLA_U16 },
2220 	[IFLA_GRE_COLLECT_METADATA] = { .type = NLA_FLAG },
2221 	[IFLA_GRE_FWMARK]       = { .type = NLA_U32 },
2222 	[IFLA_GRE_ERSPAN_INDEX] = { .type = NLA_U32 },
2223 	[IFLA_GRE_ERSPAN_VER]	= { .type = NLA_U8 },
2224 	[IFLA_GRE_ERSPAN_DIR]	= { .type = NLA_U8 },
2225 	[IFLA_GRE_ERSPAN_HWID]	= { .type = NLA_U16 },
2226 };
2227 
2228 static void ip6erspan_tap_setup(struct net_device *dev)
2229 {
2230 	ether_setup(dev);
2231 
2232 	dev->max_mtu = 0;
2233 	dev->netdev_ops = &ip6erspan_netdev_ops;
2234 	dev->needs_free_netdev = true;
2235 	dev->priv_destructor = ip6gre_dev_free;
2236 
2237 	dev->priv_flags &= ~IFF_TX_SKB_SHARING;
2238 	dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
2239 	netif_keep_dst(dev);
2240 }
2241 
2242 static int ip6erspan_newlink(struct net *src_net, struct net_device *dev,
2243 			     struct nlattr *tb[], struct nlattr *data[],
2244 			     struct netlink_ext_ack *extack)
2245 {
2246 	struct ip6_tnl *nt = netdev_priv(dev);
2247 	struct net *net = dev_net(dev);
2248 	struct ip6gre_net *ign;
2249 	int err;
2250 
2251 	ip6gre_netlink_parms(data, &nt->parms);
2252 	ip6erspan_set_version(data, &nt->parms);
2253 	ign = net_generic(net, ip6gre_net_id);
2254 
2255 	if (nt->parms.collect_md) {
2256 		if (rtnl_dereference(ign->collect_md_tun_erspan))
2257 			return -EEXIST;
2258 	} else {
2259 		if (ip6gre_tunnel_find(net, &nt->parms, dev->type))
2260 			return -EEXIST;
2261 	}
2262 
2263 	err = ip6gre_newlink_common(src_net, dev, tb, data, extack);
2264 	if (!err) {
2265 		ip6erspan_tnl_link_config(nt, !tb[IFLA_MTU]);
2266 		ip6erspan_tunnel_link_md(ign, nt);
2267 		ip6gre_tunnel_link(net_generic(net, ip6gre_net_id), nt);
2268 	}
2269 	return err;
2270 }
2271 
2272 static void ip6erspan_tnl_link_config(struct ip6_tnl *t, int set_mtu)
2273 {
2274 	ip6gre_tnl_link_config_common(t);
2275 	ip6gre_tnl_link_config_route(t, set_mtu, ip6erspan_calc_hlen(t));
2276 }
2277 
2278 static int ip6erspan_tnl_change(struct ip6_tnl *t,
2279 				const struct __ip6_tnl_parm *p, int set_mtu)
2280 {
2281 	ip6gre_tnl_copy_tnl_parm(t, p);
2282 	ip6erspan_tnl_link_config(t, set_mtu);
2283 	return 0;
2284 }
2285 
2286 static int ip6erspan_changelink(struct net_device *dev, struct nlattr *tb[],
2287 				struct nlattr *data[],
2288 				struct netlink_ext_ack *extack)
2289 {
2290 	struct ip6gre_net *ign = net_generic(dev_net(dev), ip6gre_net_id);
2291 	struct __ip6_tnl_parm p;
2292 	struct ip6_tnl *t;
2293 
2294 	t = ip6gre_changelink_common(dev, tb, data, &p, extack);
2295 	if (IS_ERR(t))
2296 		return PTR_ERR(t);
2297 
2298 	ip6erspan_set_version(data, &p);
2299 	ip6gre_tunnel_unlink_md(ign, t);
2300 	ip6gre_tunnel_unlink(ign, t);
2301 	ip6erspan_tnl_change(t, &p, !tb[IFLA_MTU]);
2302 	ip6erspan_tunnel_link_md(ign, t);
2303 	ip6gre_tunnel_link(ign, t);
2304 	return 0;
2305 }
2306 
2307 static struct rtnl_link_ops ip6gre_link_ops __read_mostly = {
2308 	.kind		= "ip6gre",
2309 	.maxtype	= IFLA_GRE_MAX,
2310 	.policy		= ip6gre_policy,
2311 	.priv_size	= sizeof(struct ip6_tnl),
2312 	.setup		= ip6gre_tunnel_setup,
2313 	.validate	= ip6gre_tunnel_validate,
2314 	.newlink	= ip6gre_newlink,
2315 	.changelink	= ip6gre_changelink,
2316 	.dellink	= ip6gre_dellink,
2317 	.get_size	= ip6gre_get_size,
2318 	.fill_info	= ip6gre_fill_info,
2319 	.get_link_net	= ip6_tnl_get_link_net,
2320 };
2321 
2322 static struct rtnl_link_ops ip6gre_tap_ops __read_mostly = {
2323 	.kind		= "ip6gretap",
2324 	.maxtype	= IFLA_GRE_MAX,
2325 	.policy		= ip6gre_policy,
2326 	.priv_size	= sizeof(struct ip6_tnl),
2327 	.setup		= ip6gre_tap_setup,
2328 	.validate	= ip6gre_tap_validate,
2329 	.newlink	= ip6gre_newlink,
2330 	.changelink	= ip6gre_changelink,
2331 	.get_size	= ip6gre_get_size,
2332 	.fill_info	= ip6gre_fill_info,
2333 	.get_link_net	= ip6_tnl_get_link_net,
2334 };
2335 
2336 static struct rtnl_link_ops ip6erspan_tap_ops __read_mostly = {
2337 	.kind		= "ip6erspan",
2338 	.maxtype	= IFLA_GRE_MAX,
2339 	.policy		= ip6gre_policy,
2340 	.priv_size	= sizeof(struct ip6_tnl),
2341 	.setup		= ip6erspan_tap_setup,
2342 	.validate	= ip6erspan_tap_validate,
2343 	.newlink	= ip6erspan_newlink,
2344 	.changelink	= ip6erspan_changelink,
2345 	.get_size	= ip6gre_get_size,
2346 	.fill_info	= ip6gre_fill_info,
2347 	.get_link_net	= ip6_tnl_get_link_net,
2348 };
2349 
2350 /*
2351  *	And now the modules code and kernel interface.
2352  */
2353 
2354 static int __init ip6gre_init(void)
2355 {
2356 	int err;
2357 
2358 	pr_info("GRE over IPv6 tunneling driver\n");
2359 
2360 	err = register_pernet_device(&ip6gre_net_ops);
2361 	if (err < 0)
2362 		return err;
2363 
2364 	err = inet6_add_protocol(&ip6gre_protocol, IPPROTO_GRE);
2365 	if (err < 0) {
2366 		pr_info("%s: can't add protocol\n", __func__);
2367 		goto add_proto_failed;
2368 	}
2369 
2370 	err = rtnl_link_register(&ip6gre_link_ops);
2371 	if (err < 0)
2372 		goto rtnl_link_failed;
2373 
2374 	err = rtnl_link_register(&ip6gre_tap_ops);
2375 	if (err < 0)
2376 		goto tap_ops_failed;
2377 
2378 	err = rtnl_link_register(&ip6erspan_tap_ops);
2379 	if (err < 0)
2380 		goto erspan_link_failed;
2381 
2382 out:
2383 	return err;
2384 
2385 erspan_link_failed:
2386 	rtnl_link_unregister(&ip6gre_tap_ops);
2387 tap_ops_failed:
2388 	rtnl_link_unregister(&ip6gre_link_ops);
2389 rtnl_link_failed:
2390 	inet6_del_protocol(&ip6gre_protocol, IPPROTO_GRE);
2391 add_proto_failed:
2392 	unregister_pernet_device(&ip6gre_net_ops);
2393 	goto out;
2394 }
2395 
2396 static void __exit ip6gre_fini(void)
2397 {
2398 	rtnl_link_unregister(&ip6gre_tap_ops);
2399 	rtnl_link_unregister(&ip6gre_link_ops);
2400 	rtnl_link_unregister(&ip6erspan_tap_ops);
2401 	inet6_del_protocol(&ip6gre_protocol, IPPROTO_GRE);
2402 	unregister_pernet_device(&ip6gre_net_ops);
2403 }
2404 
2405 module_init(ip6gre_init);
2406 module_exit(ip6gre_fini);
2407 MODULE_LICENSE("GPL");
2408 MODULE_AUTHOR("D. Kozlov (xeb@mail.ru)");
2409 MODULE_DESCRIPTION("GRE over IPv6 tunneling device");
2410 MODULE_ALIAS_RTNL_LINK("ip6gre");
2411 MODULE_ALIAS_RTNL_LINK("ip6gretap");
2412 MODULE_ALIAS_RTNL_LINK("ip6erspan");
2413 MODULE_ALIAS_NETDEV("ip6gre0");
2414