xref: /openbmc/linux/net/ipv6/ip6_gre.c (revision 97a532c3)
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 	if (unlikely(!pskb_may_pull(skb, sizeof(*ershdr))))
532 		return PACKET_REJECT;
533 
534 	ipv6h = ipv6_hdr(skb);
535 	ershdr = (struct erspan_base_hdr *)skb->data;
536 	ver = ershdr->ver;
537 
538 	tunnel = ip6gre_tunnel_lookup(skb->dev,
539 				      &ipv6h->saddr, &ipv6h->daddr, tpi->key,
540 				      tpi->proto);
541 	if (tunnel) {
542 		int len = erspan_hdr_len(ver);
543 
544 		if (unlikely(!pskb_may_pull(skb, len)))
545 			return PACKET_REJECT;
546 
547 		if (__iptunnel_pull_header(skb, len,
548 					   htons(ETH_P_TEB),
549 					   false, false) < 0)
550 			return PACKET_REJECT;
551 
552 		if (tunnel->parms.collect_md) {
553 			struct erspan_metadata *pkt_md, *md;
554 			struct metadata_dst *tun_dst;
555 			struct ip_tunnel_info *info;
556 			unsigned char *gh;
557 			__be64 tun_id;
558 			__be16 flags;
559 
560 			tpi->flags |= TUNNEL_KEY;
561 			flags = tpi->flags;
562 			tun_id = key32_to_tunnel_id(tpi->key);
563 
564 			tun_dst = ipv6_tun_rx_dst(skb, flags, tun_id,
565 						  sizeof(*md));
566 			if (!tun_dst)
567 				return PACKET_REJECT;
568 
569 			/* skb can be uncloned in __iptunnel_pull_header, so
570 			 * old pkt_md is no longer valid and we need to reset
571 			 * it
572 			 */
573 			gh = skb_network_header(skb) +
574 			     skb_network_header_len(skb);
575 			pkt_md = (struct erspan_metadata *)(gh + gre_hdr_len +
576 							    sizeof(*ershdr));
577 			info = &tun_dst->u.tun_info;
578 			md = ip_tunnel_info_opts(info);
579 			md->version = ver;
580 			md2 = &md->u.md2;
581 			memcpy(md2, pkt_md, ver == 1 ? ERSPAN_V1_MDSIZE :
582 						       ERSPAN_V2_MDSIZE);
583 			info->key.tun_flags |= TUNNEL_ERSPAN_OPT;
584 			info->options_len = sizeof(*md);
585 
586 			ip6_tnl_rcv(tunnel, skb, tpi, tun_dst, log_ecn_error);
587 
588 		} else {
589 			ip6_tnl_rcv(tunnel, skb, tpi, NULL, log_ecn_error);
590 		}
591 
592 		return PACKET_RCVD;
593 	}
594 
595 	return PACKET_REJECT;
596 }
597 
598 static int gre_rcv(struct sk_buff *skb)
599 {
600 	struct tnl_ptk_info tpi;
601 	bool csum_err = false;
602 	int hdr_len;
603 
604 	hdr_len = gre_parse_header(skb, &tpi, &csum_err, htons(ETH_P_IPV6), 0);
605 	if (hdr_len < 0)
606 		goto drop;
607 
608 	if (iptunnel_pull_header(skb, hdr_len, tpi.proto, false))
609 		goto drop;
610 
611 	if (unlikely(tpi.proto == htons(ETH_P_ERSPAN) ||
612 		     tpi.proto == htons(ETH_P_ERSPAN2))) {
613 		if (ip6erspan_rcv(skb, &tpi, hdr_len) == PACKET_RCVD)
614 			return 0;
615 		goto out;
616 	}
617 
618 	if (ip6gre_rcv(skb, &tpi) == PACKET_RCVD)
619 		return 0;
620 
621 out:
622 	icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0);
623 drop:
624 	kfree_skb(skb);
625 	return 0;
626 }
627 
628 static int gre_handle_offloads(struct sk_buff *skb, bool csum)
629 {
630 	return iptunnel_handle_offloads(skb,
631 					csum ? SKB_GSO_GRE_CSUM : SKB_GSO_GRE);
632 }
633 
634 static void prepare_ip6gre_xmit_ipv4(struct sk_buff *skb,
635 				     struct net_device *dev,
636 				     struct flowi6 *fl6, __u8 *dsfield,
637 				     int *encap_limit)
638 {
639 	const struct iphdr *iph = ip_hdr(skb);
640 	struct ip6_tnl *t = netdev_priv(dev);
641 
642 	if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
643 		*encap_limit = t->parms.encap_limit;
644 
645 	memcpy(fl6, &t->fl.u.ip6, sizeof(*fl6));
646 
647 	if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
648 		*dsfield = ipv4_get_dsfield(iph);
649 	else
650 		*dsfield = ip6_tclass(t->parms.flowinfo);
651 
652 	if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
653 		fl6->flowi6_mark = skb->mark;
654 	else
655 		fl6->flowi6_mark = t->parms.fwmark;
656 
657 	fl6->flowi6_uid = sock_net_uid(dev_net(dev), NULL);
658 }
659 
660 static int prepare_ip6gre_xmit_ipv6(struct sk_buff *skb,
661 				    struct net_device *dev,
662 				    struct flowi6 *fl6, __u8 *dsfield,
663 				    int *encap_limit)
664 {
665 	struct ipv6hdr *ipv6h;
666 	struct ip6_tnl *t = netdev_priv(dev);
667 	__u16 offset;
668 
669 	offset = ip6_tnl_parse_tlv_enc_lim(skb, skb_network_header(skb));
670 	/* ip6_tnl_parse_tlv_enc_lim() might have reallocated skb->head */
671 	ipv6h = ipv6_hdr(skb);
672 
673 	if (offset > 0) {
674 		struct ipv6_tlv_tnl_enc_lim *tel;
675 
676 		tel = (struct ipv6_tlv_tnl_enc_lim *)&skb_network_header(skb)[offset];
677 		if (tel->encap_limit == 0) {
678 			icmpv6_ndo_send(skb, ICMPV6_PARAMPROB,
679 					ICMPV6_HDR_FIELD, offset + 2);
680 			return -1;
681 		}
682 		*encap_limit = tel->encap_limit - 1;
683 	} else if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) {
684 		*encap_limit = t->parms.encap_limit;
685 	}
686 
687 	memcpy(fl6, &t->fl.u.ip6, sizeof(*fl6));
688 
689 	if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
690 		*dsfield = ipv6_get_dsfield(ipv6h);
691 	else
692 		*dsfield = ip6_tclass(t->parms.flowinfo);
693 
694 	if (t->parms.flags & IP6_TNL_F_USE_ORIG_FLOWLABEL)
695 		fl6->flowlabel |= ip6_flowlabel(ipv6h);
696 
697 	if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
698 		fl6->flowi6_mark = skb->mark;
699 	else
700 		fl6->flowi6_mark = t->parms.fwmark;
701 
702 	fl6->flowi6_uid = sock_net_uid(dev_net(dev), NULL);
703 
704 	return 0;
705 }
706 
707 static int prepare_ip6gre_xmit_other(struct sk_buff *skb,
708 				     struct net_device *dev,
709 				     struct flowi6 *fl6, __u8 *dsfield,
710 				     int *encap_limit)
711 {
712 	struct ip6_tnl *t = netdev_priv(dev);
713 
714 	if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
715 		*encap_limit = t->parms.encap_limit;
716 
717 	memcpy(fl6, &t->fl.u.ip6, sizeof(*fl6));
718 
719 	if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
720 		*dsfield = 0;
721 	else
722 		*dsfield = ip6_tclass(t->parms.flowinfo);
723 
724 	if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
725 		fl6->flowi6_mark = skb->mark;
726 	else
727 		fl6->flowi6_mark = t->parms.fwmark;
728 
729 	fl6->flowi6_uid = sock_net_uid(dev_net(dev), NULL);
730 
731 	return 0;
732 }
733 
734 static struct ip_tunnel_info *skb_tunnel_info_txcheck(struct sk_buff *skb)
735 {
736 	struct ip_tunnel_info *tun_info;
737 
738 	tun_info = skb_tunnel_info(skb);
739 	if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX)))
740 		return ERR_PTR(-EINVAL);
741 
742 	return tun_info;
743 }
744 
745 static netdev_tx_t __gre6_xmit(struct sk_buff *skb,
746 			       struct net_device *dev, __u8 dsfield,
747 			       struct flowi6 *fl6, int encap_limit,
748 			       __u32 *pmtu, __be16 proto)
749 {
750 	struct ip6_tnl *tunnel = netdev_priv(dev);
751 	__be16 protocol;
752 	__be16 flags;
753 
754 	if (dev->type == ARPHRD_ETHER)
755 		IPCB(skb)->flags = 0;
756 
757 	if (dev->header_ops && dev->type == ARPHRD_IP6GRE)
758 		fl6->daddr = ((struct ipv6hdr *)skb->data)->daddr;
759 	else
760 		fl6->daddr = tunnel->parms.raddr;
761 
762 	/* Push GRE header. */
763 	protocol = (dev->type == ARPHRD_ETHER) ? htons(ETH_P_TEB) : proto;
764 
765 	if (tunnel->parms.collect_md) {
766 		struct ip_tunnel_info *tun_info;
767 		const struct ip_tunnel_key *key;
768 		int tun_hlen;
769 
770 		tun_info = skb_tunnel_info_txcheck(skb);
771 		if (IS_ERR(tun_info) ||
772 		    unlikely(ip_tunnel_info_af(tun_info) != AF_INET6))
773 			return -EINVAL;
774 
775 		key = &tun_info->key;
776 		memset(fl6, 0, sizeof(*fl6));
777 		fl6->flowi6_proto = IPPROTO_GRE;
778 		fl6->daddr = key->u.ipv6.dst;
779 		fl6->flowlabel = key->label;
780 		fl6->flowi6_uid = sock_net_uid(dev_net(dev), NULL);
781 		fl6->fl6_gre_key = tunnel_id_to_key32(key->tun_id);
782 
783 		dsfield = key->tos;
784 		flags = key->tun_flags &
785 			(TUNNEL_CSUM | TUNNEL_KEY | TUNNEL_SEQ);
786 		tun_hlen = gre_calc_hlen(flags);
787 
788 		if (skb_cow_head(skb, dev->needed_headroom ?: tun_hlen + tunnel->encap_hlen))
789 			return -ENOMEM;
790 
791 		gre_build_header(skb, tun_hlen,
792 				 flags, protocol,
793 				 tunnel_id_to_key32(tun_info->key.tun_id),
794 				 (flags & TUNNEL_SEQ) ? htonl(atomic_fetch_inc(&tunnel->o_seqno))
795 						      : 0);
796 
797 	} else {
798 		if (skb_cow_head(skb, dev->needed_headroom ?: tunnel->hlen))
799 			return -ENOMEM;
800 
801 		flags = tunnel->parms.o_flags;
802 
803 		gre_build_header(skb, tunnel->tun_hlen, flags,
804 				 protocol, tunnel->parms.o_key,
805 				 (flags & TUNNEL_SEQ) ? htonl(atomic_fetch_inc(&tunnel->o_seqno))
806 						      : 0);
807 	}
808 
809 	return ip6_tnl_xmit(skb, dev, dsfield, fl6, encap_limit, pmtu,
810 			    NEXTHDR_GRE);
811 }
812 
813 static inline int ip6gre_xmit_ipv4(struct sk_buff *skb, struct net_device *dev)
814 {
815 	struct ip6_tnl *t = netdev_priv(dev);
816 	int encap_limit = -1;
817 	struct flowi6 fl6;
818 	__u8 dsfield = 0;
819 	__u32 mtu;
820 	int err;
821 
822 	memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
823 
824 	if (!t->parms.collect_md)
825 		prepare_ip6gre_xmit_ipv4(skb, dev, &fl6,
826 					 &dsfield, &encap_limit);
827 
828 	err = gre_handle_offloads(skb, !!(t->parms.o_flags & TUNNEL_CSUM));
829 	if (err)
830 		return -1;
831 
832 	err = __gre6_xmit(skb, dev, dsfield, &fl6, encap_limit, &mtu,
833 			  skb->protocol);
834 	if (err != 0) {
835 		/* XXX: send ICMP error even if DF is not set. */
836 		if (err == -EMSGSIZE)
837 			icmp_ndo_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
838 				      htonl(mtu));
839 		return -1;
840 	}
841 
842 	return 0;
843 }
844 
845 static inline int ip6gre_xmit_ipv6(struct sk_buff *skb, struct net_device *dev)
846 {
847 	struct ip6_tnl *t = netdev_priv(dev);
848 	struct ipv6hdr *ipv6h = ipv6_hdr(skb);
849 	int encap_limit = -1;
850 	struct flowi6 fl6;
851 	__u8 dsfield = 0;
852 	__u32 mtu;
853 	int err;
854 
855 	if (ipv6_addr_equal(&t->parms.raddr, &ipv6h->saddr))
856 		return -1;
857 
858 	if (!t->parms.collect_md &&
859 	    prepare_ip6gre_xmit_ipv6(skb, dev, &fl6, &dsfield, &encap_limit))
860 		return -1;
861 
862 	if (gre_handle_offloads(skb, !!(t->parms.o_flags & TUNNEL_CSUM)))
863 		return -1;
864 
865 	err = __gre6_xmit(skb, dev, dsfield, &fl6, encap_limit,
866 			  &mtu, skb->protocol);
867 	if (err != 0) {
868 		if (err == -EMSGSIZE)
869 			icmpv6_ndo_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
870 		return -1;
871 	}
872 
873 	return 0;
874 }
875 
876 static int ip6gre_xmit_other(struct sk_buff *skb, struct net_device *dev)
877 {
878 	struct ip6_tnl *t = netdev_priv(dev);
879 	int encap_limit = -1;
880 	struct flowi6 fl6;
881 	__u8 dsfield = 0;
882 	__u32 mtu;
883 	int err;
884 
885 	if (!t->parms.collect_md &&
886 	    prepare_ip6gre_xmit_other(skb, dev, &fl6, &dsfield, &encap_limit))
887 		return -1;
888 
889 	err = gre_handle_offloads(skb, !!(t->parms.o_flags & TUNNEL_CSUM));
890 	if (err)
891 		return err;
892 	err = __gre6_xmit(skb, dev, dsfield, &fl6, encap_limit, &mtu, skb->protocol);
893 
894 	return err;
895 }
896 
897 static netdev_tx_t ip6gre_tunnel_xmit(struct sk_buff *skb,
898 	struct net_device *dev)
899 {
900 	struct ip6_tnl *t = netdev_priv(dev);
901 	__be16 payload_protocol;
902 	int ret;
903 
904 	if (!pskb_inet_may_pull(skb))
905 		goto tx_err;
906 
907 	if (!ip6_tnl_xmit_ctl(t, &t->parms.laddr, &t->parms.raddr))
908 		goto tx_err;
909 
910 	payload_protocol = skb_protocol(skb, true);
911 	switch (payload_protocol) {
912 	case htons(ETH_P_IP):
913 		ret = ip6gre_xmit_ipv4(skb, dev);
914 		break;
915 	case htons(ETH_P_IPV6):
916 		ret = ip6gre_xmit_ipv6(skb, dev);
917 		break;
918 	default:
919 		ret = ip6gre_xmit_other(skb, dev);
920 		break;
921 	}
922 
923 	if (ret < 0)
924 		goto tx_err;
925 
926 	return NETDEV_TX_OK;
927 
928 tx_err:
929 	if (!t->parms.collect_md || !IS_ERR(skb_tunnel_info_txcheck(skb)))
930 		DEV_STATS_INC(dev, tx_errors);
931 	DEV_STATS_INC(dev, tx_dropped);
932 	kfree_skb(skb);
933 	return NETDEV_TX_OK;
934 }
935 
936 static netdev_tx_t ip6erspan_tunnel_xmit(struct sk_buff *skb,
937 					 struct net_device *dev)
938 {
939 	struct ip_tunnel_info *tun_info = NULL;
940 	struct ip6_tnl *t = netdev_priv(dev);
941 	struct dst_entry *dst = skb_dst(skb);
942 	bool truncate = false;
943 	int encap_limit = -1;
944 	__u8 dsfield = false;
945 	struct flowi6 fl6;
946 	int err = -EINVAL;
947 	__be16 proto;
948 	__u32 mtu;
949 	int nhoff;
950 
951 	if (!pskb_inet_may_pull(skb))
952 		goto tx_err;
953 
954 	if (!ip6_tnl_xmit_ctl(t, &t->parms.laddr, &t->parms.raddr))
955 		goto tx_err;
956 
957 	if (gre_handle_offloads(skb, false))
958 		goto tx_err;
959 
960 	if (skb->len > dev->mtu + dev->hard_header_len) {
961 		if (pskb_trim(skb, dev->mtu + dev->hard_header_len))
962 			goto tx_err;
963 		truncate = true;
964 	}
965 
966 	nhoff = skb_network_offset(skb);
967 	if (skb->protocol == htons(ETH_P_IP) &&
968 	    (ntohs(ip_hdr(skb)->tot_len) > skb->len - nhoff))
969 		truncate = true;
970 
971 	if (skb->protocol == htons(ETH_P_IPV6)) {
972 		int thoff;
973 
974 		if (skb_transport_header_was_set(skb))
975 			thoff = skb_transport_offset(skb);
976 		else
977 			thoff = nhoff + sizeof(struct ipv6hdr);
978 		if (ntohs(ipv6_hdr(skb)->payload_len) > skb->len - thoff)
979 			truncate = true;
980 	}
981 
982 	if (skb_cow_head(skb, dev->needed_headroom ?: t->hlen))
983 		goto tx_err;
984 
985 	t->parms.o_flags &= ~TUNNEL_KEY;
986 	IPCB(skb)->flags = 0;
987 
988 	/* For collect_md mode, derive fl6 from the tunnel key,
989 	 * for native mode, call prepare_ip6gre_xmit_{ipv4,ipv6}.
990 	 */
991 	if (t->parms.collect_md) {
992 		const struct ip_tunnel_key *key;
993 		struct erspan_metadata *md;
994 		__be32 tun_id;
995 
996 		tun_info = skb_tunnel_info_txcheck(skb);
997 		if (IS_ERR(tun_info) ||
998 		    unlikely(ip_tunnel_info_af(tun_info) != AF_INET6))
999 			goto tx_err;
1000 
1001 		key = &tun_info->key;
1002 		memset(&fl6, 0, sizeof(fl6));
1003 		fl6.flowi6_proto = IPPROTO_GRE;
1004 		fl6.daddr = key->u.ipv6.dst;
1005 		fl6.flowlabel = key->label;
1006 		fl6.flowi6_uid = sock_net_uid(dev_net(dev), NULL);
1007 		fl6.fl6_gre_key = tunnel_id_to_key32(key->tun_id);
1008 
1009 		dsfield = key->tos;
1010 		if (!(tun_info->key.tun_flags & TUNNEL_ERSPAN_OPT))
1011 			goto tx_err;
1012 		if (tun_info->options_len < sizeof(*md))
1013 			goto tx_err;
1014 		md = ip_tunnel_info_opts(tun_info);
1015 
1016 		tun_id = tunnel_id_to_key32(key->tun_id);
1017 		if (md->version == 1) {
1018 			erspan_build_header(skb,
1019 					    ntohl(tun_id),
1020 					    ntohl(md->u.index), truncate,
1021 					    false);
1022 			proto = htons(ETH_P_ERSPAN);
1023 		} else if (md->version == 2) {
1024 			erspan_build_header_v2(skb,
1025 					       ntohl(tun_id),
1026 					       md->u.md2.dir,
1027 					       get_hwid(&md->u.md2),
1028 					       truncate, false);
1029 			proto = htons(ETH_P_ERSPAN2);
1030 		} else {
1031 			goto tx_err;
1032 		}
1033 	} else {
1034 		switch (skb->protocol) {
1035 		case htons(ETH_P_IP):
1036 			memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
1037 			prepare_ip6gre_xmit_ipv4(skb, dev, &fl6,
1038 						 &dsfield, &encap_limit);
1039 			break;
1040 		case htons(ETH_P_IPV6):
1041 			if (ipv6_addr_equal(&t->parms.raddr, &ipv6_hdr(skb)->saddr))
1042 				goto tx_err;
1043 			if (prepare_ip6gre_xmit_ipv6(skb, dev, &fl6,
1044 						     &dsfield, &encap_limit))
1045 				goto tx_err;
1046 			break;
1047 		default:
1048 			memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6));
1049 			break;
1050 		}
1051 
1052 		if (t->parms.erspan_ver == 1) {
1053 			erspan_build_header(skb, ntohl(t->parms.o_key),
1054 					    t->parms.index,
1055 					    truncate, false);
1056 			proto = htons(ETH_P_ERSPAN);
1057 		} else if (t->parms.erspan_ver == 2) {
1058 			erspan_build_header_v2(skb, ntohl(t->parms.o_key),
1059 					       t->parms.dir,
1060 					       t->parms.hwid,
1061 					       truncate, false);
1062 			proto = htons(ETH_P_ERSPAN2);
1063 		} else {
1064 			goto tx_err;
1065 		}
1066 
1067 		fl6.daddr = t->parms.raddr;
1068 	}
1069 
1070 	/* Push GRE header. */
1071 	gre_build_header(skb, 8, TUNNEL_SEQ, proto, 0, htonl(atomic_fetch_inc(&t->o_seqno)));
1072 
1073 	/* TooBig packet may have updated dst->dev's mtu */
1074 	if (!t->parms.collect_md && dst && dst_mtu(dst) > dst->dev->mtu)
1075 		dst->ops->update_pmtu(dst, NULL, skb, dst->dev->mtu, false);
1076 
1077 	err = ip6_tnl_xmit(skb, dev, dsfield, &fl6, encap_limit, &mtu,
1078 			   NEXTHDR_GRE);
1079 	if (err != 0) {
1080 		/* XXX: send ICMP error even if DF is not set. */
1081 		if (err == -EMSGSIZE) {
1082 			if (skb->protocol == htons(ETH_P_IP))
1083 				icmp_ndo_send(skb, ICMP_DEST_UNREACH,
1084 					      ICMP_FRAG_NEEDED, htonl(mtu));
1085 			else
1086 				icmpv6_ndo_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
1087 		}
1088 
1089 		goto tx_err;
1090 	}
1091 	return NETDEV_TX_OK;
1092 
1093 tx_err:
1094 	if (!IS_ERR(tun_info))
1095 		DEV_STATS_INC(dev, tx_errors);
1096 	DEV_STATS_INC(dev, tx_dropped);
1097 	kfree_skb(skb);
1098 	return NETDEV_TX_OK;
1099 }
1100 
1101 static void ip6gre_tnl_link_config_common(struct ip6_tnl *t)
1102 {
1103 	struct net_device *dev = t->dev;
1104 	struct __ip6_tnl_parm *p = &t->parms;
1105 	struct flowi6 *fl6 = &t->fl.u.ip6;
1106 
1107 	if (dev->type != ARPHRD_ETHER) {
1108 		__dev_addr_set(dev, &p->laddr, sizeof(struct in6_addr));
1109 		memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr));
1110 	}
1111 
1112 	/* Set up flowi template */
1113 	fl6->saddr = p->laddr;
1114 	fl6->daddr = p->raddr;
1115 	fl6->flowi6_oif = p->link;
1116 	fl6->flowlabel = 0;
1117 	fl6->flowi6_proto = IPPROTO_GRE;
1118 	fl6->fl6_gre_key = t->parms.o_key;
1119 
1120 	if (!(p->flags&IP6_TNL_F_USE_ORIG_TCLASS))
1121 		fl6->flowlabel |= IPV6_TCLASS_MASK & p->flowinfo;
1122 	if (!(p->flags&IP6_TNL_F_USE_ORIG_FLOWLABEL))
1123 		fl6->flowlabel |= IPV6_FLOWLABEL_MASK & p->flowinfo;
1124 
1125 	p->flags &= ~(IP6_TNL_F_CAP_XMIT|IP6_TNL_F_CAP_RCV|IP6_TNL_F_CAP_PER_PACKET);
1126 	p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr);
1127 
1128 	if (p->flags&IP6_TNL_F_CAP_XMIT &&
1129 			p->flags&IP6_TNL_F_CAP_RCV && dev->type != ARPHRD_ETHER)
1130 		dev->flags |= IFF_POINTOPOINT;
1131 	else
1132 		dev->flags &= ~IFF_POINTOPOINT;
1133 }
1134 
1135 static void ip6gre_tnl_link_config_route(struct ip6_tnl *t, int set_mtu,
1136 					 int t_hlen)
1137 {
1138 	const struct __ip6_tnl_parm *p = &t->parms;
1139 	struct net_device *dev = t->dev;
1140 
1141 	if (p->flags & IP6_TNL_F_CAP_XMIT) {
1142 		int strict = (ipv6_addr_type(&p->raddr) &
1143 			      (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL));
1144 
1145 		struct rt6_info *rt = rt6_lookup(t->net,
1146 						 &p->raddr, &p->laddr,
1147 						 p->link, NULL, strict);
1148 
1149 		if (!rt)
1150 			return;
1151 
1152 		if (rt->dst.dev) {
1153 			unsigned short dst_len = rt->dst.dev->hard_header_len +
1154 						 t_hlen;
1155 
1156 			if (t->dev->header_ops)
1157 				dev->hard_header_len = dst_len;
1158 			else
1159 				dev->needed_headroom = dst_len;
1160 
1161 			if (set_mtu) {
1162 				int mtu = rt->dst.dev->mtu - t_hlen;
1163 
1164 				if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1165 					mtu -= 8;
1166 				if (dev->type == ARPHRD_ETHER)
1167 					mtu -= ETH_HLEN;
1168 
1169 				if (mtu < IPV6_MIN_MTU)
1170 					mtu = IPV6_MIN_MTU;
1171 				WRITE_ONCE(dev->mtu, mtu);
1172 			}
1173 		}
1174 		ip6_rt_put(rt);
1175 	}
1176 }
1177 
1178 static int ip6gre_calc_hlen(struct ip6_tnl *tunnel)
1179 {
1180 	int t_hlen;
1181 
1182 	tunnel->tun_hlen = gre_calc_hlen(tunnel->parms.o_flags);
1183 	tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen;
1184 
1185 	t_hlen = tunnel->hlen + sizeof(struct ipv6hdr);
1186 
1187 	if (tunnel->dev->header_ops)
1188 		tunnel->dev->hard_header_len = LL_MAX_HEADER + t_hlen;
1189 	else
1190 		tunnel->dev->needed_headroom = LL_MAX_HEADER + t_hlen;
1191 
1192 	return t_hlen;
1193 }
1194 
1195 static void ip6gre_tnl_link_config(struct ip6_tnl *t, int set_mtu)
1196 {
1197 	ip6gre_tnl_link_config_common(t);
1198 	ip6gre_tnl_link_config_route(t, set_mtu, ip6gre_calc_hlen(t));
1199 }
1200 
1201 static void ip6gre_tnl_copy_tnl_parm(struct ip6_tnl *t,
1202 				     const struct __ip6_tnl_parm *p)
1203 {
1204 	t->parms.laddr = p->laddr;
1205 	t->parms.raddr = p->raddr;
1206 	t->parms.flags = p->flags;
1207 	t->parms.hop_limit = p->hop_limit;
1208 	t->parms.encap_limit = p->encap_limit;
1209 	t->parms.flowinfo = p->flowinfo;
1210 	t->parms.link = p->link;
1211 	t->parms.proto = p->proto;
1212 	t->parms.i_key = p->i_key;
1213 	t->parms.o_key = p->o_key;
1214 	t->parms.i_flags = p->i_flags;
1215 	t->parms.o_flags = p->o_flags;
1216 	t->parms.fwmark = p->fwmark;
1217 	t->parms.erspan_ver = p->erspan_ver;
1218 	t->parms.index = p->index;
1219 	t->parms.dir = p->dir;
1220 	t->parms.hwid = p->hwid;
1221 	dst_cache_reset(&t->dst_cache);
1222 }
1223 
1224 static int ip6gre_tnl_change(struct ip6_tnl *t, const struct __ip6_tnl_parm *p,
1225 			     int set_mtu)
1226 {
1227 	ip6gre_tnl_copy_tnl_parm(t, p);
1228 	ip6gre_tnl_link_config(t, set_mtu);
1229 	return 0;
1230 }
1231 
1232 static void ip6gre_tnl_parm_from_user(struct __ip6_tnl_parm *p,
1233 	const struct ip6_tnl_parm2 *u)
1234 {
1235 	p->laddr = u->laddr;
1236 	p->raddr = u->raddr;
1237 	p->flags = u->flags;
1238 	p->hop_limit = u->hop_limit;
1239 	p->encap_limit = u->encap_limit;
1240 	p->flowinfo = u->flowinfo;
1241 	p->link = u->link;
1242 	p->i_key = u->i_key;
1243 	p->o_key = u->o_key;
1244 	p->i_flags = gre_flags_to_tnl_flags(u->i_flags);
1245 	p->o_flags = gre_flags_to_tnl_flags(u->o_flags);
1246 	memcpy(p->name, u->name, sizeof(u->name));
1247 }
1248 
1249 static void ip6gre_tnl_parm_to_user(struct ip6_tnl_parm2 *u,
1250 	const struct __ip6_tnl_parm *p)
1251 {
1252 	u->proto = IPPROTO_GRE;
1253 	u->laddr = p->laddr;
1254 	u->raddr = p->raddr;
1255 	u->flags = p->flags;
1256 	u->hop_limit = p->hop_limit;
1257 	u->encap_limit = p->encap_limit;
1258 	u->flowinfo = p->flowinfo;
1259 	u->link = p->link;
1260 	u->i_key = p->i_key;
1261 	u->o_key = p->o_key;
1262 	u->i_flags = gre_tnl_flags_to_gre_flags(p->i_flags);
1263 	u->o_flags = gre_tnl_flags_to_gre_flags(p->o_flags);
1264 	memcpy(u->name, p->name, sizeof(u->name));
1265 }
1266 
1267 static int ip6gre_tunnel_siocdevprivate(struct net_device *dev,
1268 					struct ifreq *ifr, void __user *data,
1269 					int cmd)
1270 {
1271 	int err = 0;
1272 	struct ip6_tnl_parm2 p;
1273 	struct __ip6_tnl_parm p1;
1274 	struct ip6_tnl *t = netdev_priv(dev);
1275 	struct net *net = t->net;
1276 	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
1277 
1278 	memset(&p1, 0, sizeof(p1));
1279 
1280 	switch (cmd) {
1281 	case SIOCGETTUNNEL:
1282 		if (dev == ign->fb_tunnel_dev) {
1283 			if (copy_from_user(&p, data, sizeof(p))) {
1284 				err = -EFAULT;
1285 				break;
1286 			}
1287 			ip6gre_tnl_parm_from_user(&p1, &p);
1288 			t = ip6gre_tunnel_locate(net, &p1, 0);
1289 			if (!t)
1290 				t = netdev_priv(dev);
1291 		}
1292 		memset(&p, 0, sizeof(p));
1293 		ip6gre_tnl_parm_to_user(&p, &t->parms);
1294 		if (copy_to_user(data, &p, sizeof(p)))
1295 			err = -EFAULT;
1296 		break;
1297 
1298 	case SIOCADDTUNNEL:
1299 	case SIOCCHGTUNNEL:
1300 		err = -EPERM;
1301 		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1302 			goto done;
1303 
1304 		err = -EFAULT;
1305 		if (copy_from_user(&p, data, sizeof(p)))
1306 			goto done;
1307 
1308 		err = -EINVAL;
1309 		if ((p.i_flags|p.o_flags)&(GRE_VERSION|GRE_ROUTING))
1310 			goto done;
1311 
1312 		if (!(p.i_flags&GRE_KEY))
1313 			p.i_key = 0;
1314 		if (!(p.o_flags&GRE_KEY))
1315 			p.o_key = 0;
1316 
1317 		ip6gre_tnl_parm_from_user(&p1, &p);
1318 		t = ip6gre_tunnel_locate(net, &p1, cmd == SIOCADDTUNNEL);
1319 
1320 		if (dev != ign->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) {
1321 			if (t) {
1322 				if (t->dev != dev) {
1323 					err = -EEXIST;
1324 					break;
1325 				}
1326 			} else {
1327 				t = netdev_priv(dev);
1328 
1329 				ip6gre_tunnel_unlink(ign, t);
1330 				synchronize_net();
1331 				ip6gre_tnl_change(t, &p1, 1);
1332 				ip6gre_tunnel_link(ign, t);
1333 				netdev_state_change(dev);
1334 			}
1335 		}
1336 
1337 		if (t) {
1338 			err = 0;
1339 
1340 			memset(&p, 0, sizeof(p));
1341 			ip6gre_tnl_parm_to_user(&p, &t->parms);
1342 			if (copy_to_user(data, &p, sizeof(p)))
1343 				err = -EFAULT;
1344 		} else
1345 			err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
1346 		break;
1347 
1348 	case SIOCDELTUNNEL:
1349 		err = -EPERM;
1350 		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1351 			goto done;
1352 
1353 		if (dev == ign->fb_tunnel_dev) {
1354 			err = -EFAULT;
1355 			if (copy_from_user(&p, data, sizeof(p)))
1356 				goto done;
1357 			err = -ENOENT;
1358 			ip6gre_tnl_parm_from_user(&p1, &p);
1359 			t = ip6gre_tunnel_locate(net, &p1, 0);
1360 			if (!t)
1361 				goto done;
1362 			err = -EPERM;
1363 			if (t == netdev_priv(ign->fb_tunnel_dev))
1364 				goto done;
1365 			dev = t->dev;
1366 		}
1367 		unregister_netdevice(dev);
1368 		err = 0;
1369 		break;
1370 
1371 	default:
1372 		err = -EINVAL;
1373 	}
1374 
1375 done:
1376 	return err;
1377 }
1378 
1379 static int ip6gre_header(struct sk_buff *skb, struct net_device *dev,
1380 			 unsigned short type, const void *daddr,
1381 			 const void *saddr, unsigned int len)
1382 {
1383 	struct ip6_tnl *t = netdev_priv(dev);
1384 	struct ipv6hdr *ipv6h;
1385 	__be16 *p;
1386 
1387 	ipv6h = skb_push(skb, t->hlen + sizeof(*ipv6h));
1388 	ip6_flow_hdr(ipv6h, 0, ip6_make_flowlabel(dev_net(dev), skb,
1389 						  t->fl.u.ip6.flowlabel,
1390 						  true, &t->fl.u.ip6));
1391 	ipv6h->hop_limit = t->parms.hop_limit;
1392 	ipv6h->nexthdr = NEXTHDR_GRE;
1393 	ipv6h->saddr = t->parms.laddr;
1394 	ipv6h->daddr = t->parms.raddr;
1395 
1396 	p = (__be16 *)(ipv6h + 1);
1397 	p[0] = t->parms.o_flags;
1398 	p[1] = htons(type);
1399 
1400 	/*
1401 	 *	Set the source hardware address.
1402 	 */
1403 
1404 	if (saddr)
1405 		memcpy(&ipv6h->saddr, saddr, sizeof(struct in6_addr));
1406 	if (daddr)
1407 		memcpy(&ipv6h->daddr, daddr, sizeof(struct in6_addr));
1408 	if (!ipv6_addr_any(&ipv6h->daddr))
1409 		return t->hlen;
1410 
1411 	return -t->hlen;
1412 }
1413 
1414 static const struct header_ops ip6gre_header_ops = {
1415 	.create	= ip6gre_header,
1416 };
1417 
1418 static const struct net_device_ops ip6gre_netdev_ops = {
1419 	.ndo_init		= ip6gre_tunnel_init,
1420 	.ndo_uninit		= ip6gre_tunnel_uninit,
1421 	.ndo_start_xmit		= ip6gre_tunnel_xmit,
1422 	.ndo_siocdevprivate	= ip6gre_tunnel_siocdevprivate,
1423 	.ndo_change_mtu		= ip6_tnl_change_mtu,
1424 	.ndo_get_stats64	= dev_get_tstats64,
1425 	.ndo_get_iflink		= ip6_tnl_get_iflink,
1426 };
1427 
1428 static void ip6gre_dev_free(struct net_device *dev)
1429 {
1430 	struct ip6_tnl *t = netdev_priv(dev);
1431 
1432 	gro_cells_destroy(&t->gro_cells);
1433 	dst_cache_destroy(&t->dst_cache);
1434 	free_percpu(dev->tstats);
1435 }
1436 
1437 static void ip6gre_tunnel_setup(struct net_device *dev)
1438 {
1439 	dev->netdev_ops = &ip6gre_netdev_ops;
1440 	dev->needs_free_netdev = true;
1441 	dev->priv_destructor = ip6gre_dev_free;
1442 
1443 	dev->type = ARPHRD_IP6GRE;
1444 
1445 	dev->flags |= IFF_NOARP;
1446 	dev->addr_len = sizeof(struct in6_addr);
1447 	netif_keep_dst(dev);
1448 	/* This perm addr will be used as interface identifier by IPv6 */
1449 	dev->addr_assign_type = NET_ADDR_RANDOM;
1450 	eth_random_addr(dev->perm_addr);
1451 }
1452 
1453 #define GRE6_FEATURES (NETIF_F_SG |		\
1454 		       NETIF_F_FRAGLIST |	\
1455 		       NETIF_F_HIGHDMA |	\
1456 		       NETIF_F_HW_CSUM)
1457 
1458 static void ip6gre_tnl_init_features(struct net_device *dev)
1459 {
1460 	struct ip6_tnl *nt = netdev_priv(dev);
1461 	__be16 flags;
1462 
1463 	dev->features		|= GRE6_FEATURES | NETIF_F_LLTX;
1464 	dev->hw_features	|= GRE6_FEATURES;
1465 
1466 	flags = nt->parms.o_flags;
1467 
1468 	/* TCP offload with GRE SEQ is not supported, nor can we support 2
1469 	 * levels of outer headers requiring an update.
1470 	 */
1471 	if (flags & TUNNEL_SEQ)
1472 		return;
1473 	if (flags & TUNNEL_CSUM && nt->encap.type != TUNNEL_ENCAP_NONE)
1474 		return;
1475 
1476 	dev->features |= NETIF_F_GSO_SOFTWARE;
1477 	dev->hw_features |= NETIF_F_GSO_SOFTWARE;
1478 }
1479 
1480 static int ip6gre_tunnel_init_common(struct net_device *dev)
1481 {
1482 	struct ip6_tnl *tunnel;
1483 	int ret;
1484 	int t_hlen;
1485 
1486 	tunnel = netdev_priv(dev);
1487 
1488 	tunnel->dev = dev;
1489 	tunnel->net = dev_net(dev);
1490 	strcpy(tunnel->parms.name, dev->name);
1491 
1492 	dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
1493 	if (!dev->tstats)
1494 		return -ENOMEM;
1495 
1496 	ret = dst_cache_init(&tunnel->dst_cache, GFP_KERNEL);
1497 	if (ret)
1498 		goto cleanup_alloc_pcpu_stats;
1499 
1500 	ret = gro_cells_init(&tunnel->gro_cells, dev);
1501 	if (ret)
1502 		goto cleanup_dst_cache_init;
1503 
1504 	t_hlen = ip6gre_calc_hlen(tunnel);
1505 	dev->mtu = ETH_DATA_LEN - t_hlen;
1506 	if (dev->type == ARPHRD_ETHER)
1507 		dev->mtu -= ETH_HLEN;
1508 	if (!(tunnel->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1509 		dev->mtu -= 8;
1510 
1511 	if (tunnel->parms.collect_md) {
1512 		netif_keep_dst(dev);
1513 	}
1514 	ip6gre_tnl_init_features(dev);
1515 
1516 	netdev_hold(dev, &tunnel->dev_tracker, GFP_KERNEL);
1517 	netdev_lockdep_set_classes(dev);
1518 	return 0;
1519 
1520 cleanup_dst_cache_init:
1521 	dst_cache_destroy(&tunnel->dst_cache);
1522 cleanup_alloc_pcpu_stats:
1523 	free_percpu(dev->tstats);
1524 	dev->tstats = NULL;
1525 	return ret;
1526 }
1527 
1528 static int ip6gre_tunnel_init(struct net_device *dev)
1529 {
1530 	struct ip6_tnl *tunnel;
1531 	int ret;
1532 
1533 	ret = ip6gre_tunnel_init_common(dev);
1534 	if (ret)
1535 		return ret;
1536 
1537 	tunnel = netdev_priv(dev);
1538 
1539 	if (tunnel->parms.collect_md)
1540 		return 0;
1541 
1542 	__dev_addr_set(dev, &tunnel->parms.laddr, sizeof(struct in6_addr));
1543 	memcpy(dev->broadcast, &tunnel->parms.raddr, sizeof(struct in6_addr));
1544 
1545 	if (ipv6_addr_any(&tunnel->parms.raddr))
1546 		dev->header_ops = &ip6gre_header_ops;
1547 
1548 	return 0;
1549 }
1550 
1551 static void ip6gre_fb_tunnel_init(struct net_device *dev)
1552 {
1553 	struct ip6_tnl *tunnel = netdev_priv(dev);
1554 
1555 	tunnel->dev = dev;
1556 	tunnel->net = dev_net(dev);
1557 	strcpy(tunnel->parms.name, dev->name);
1558 
1559 	tunnel->hlen		= sizeof(struct ipv6hdr) + 4;
1560 }
1561 
1562 static struct inet6_protocol ip6gre_protocol __read_mostly = {
1563 	.handler     = gre_rcv,
1564 	.err_handler = ip6gre_err,
1565 	.flags       = INET6_PROTO_FINAL,
1566 };
1567 
1568 static void ip6gre_destroy_tunnels(struct net *net, struct list_head *head)
1569 {
1570 	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
1571 	struct net_device *dev, *aux;
1572 	int prio;
1573 
1574 	for_each_netdev_safe(net, dev, aux)
1575 		if (dev->rtnl_link_ops == &ip6gre_link_ops ||
1576 		    dev->rtnl_link_ops == &ip6gre_tap_ops ||
1577 		    dev->rtnl_link_ops == &ip6erspan_tap_ops)
1578 			unregister_netdevice_queue(dev, head);
1579 
1580 	for (prio = 0; prio < 4; prio++) {
1581 		int h;
1582 		for (h = 0; h < IP6_GRE_HASH_SIZE; h++) {
1583 			struct ip6_tnl *t;
1584 
1585 			t = rtnl_dereference(ign->tunnels[prio][h]);
1586 
1587 			while (t) {
1588 				/* If dev is in the same netns, it has already
1589 				 * been added to the list by the previous loop.
1590 				 */
1591 				if (!net_eq(dev_net(t->dev), net))
1592 					unregister_netdevice_queue(t->dev,
1593 								   head);
1594 				t = rtnl_dereference(t->next);
1595 			}
1596 		}
1597 	}
1598 }
1599 
1600 static int __net_init ip6gre_init_net(struct net *net)
1601 {
1602 	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
1603 	struct net_device *ndev;
1604 	int err;
1605 
1606 	if (!net_has_fallback_tunnels(net))
1607 		return 0;
1608 	ndev = alloc_netdev(sizeof(struct ip6_tnl), "ip6gre0",
1609 			    NET_NAME_UNKNOWN, ip6gre_tunnel_setup);
1610 	if (!ndev) {
1611 		err = -ENOMEM;
1612 		goto err_alloc_dev;
1613 	}
1614 	ign->fb_tunnel_dev = ndev;
1615 	dev_net_set(ign->fb_tunnel_dev, net);
1616 	/* FB netdevice is special: we have one, and only one per netns.
1617 	 * Allowing to move it to another netns is clearly unsafe.
1618 	 */
1619 	ign->fb_tunnel_dev->features |= NETIF_F_NETNS_LOCAL;
1620 
1621 
1622 	ip6gre_fb_tunnel_init(ign->fb_tunnel_dev);
1623 	ign->fb_tunnel_dev->rtnl_link_ops = &ip6gre_link_ops;
1624 
1625 	err = register_netdev(ign->fb_tunnel_dev);
1626 	if (err)
1627 		goto err_reg_dev;
1628 
1629 	rcu_assign_pointer(ign->tunnels_wc[0],
1630 			   netdev_priv(ign->fb_tunnel_dev));
1631 	return 0;
1632 
1633 err_reg_dev:
1634 	free_netdev(ndev);
1635 err_alloc_dev:
1636 	return err;
1637 }
1638 
1639 static void __net_exit ip6gre_exit_batch_net(struct list_head *net_list)
1640 {
1641 	struct net *net;
1642 	LIST_HEAD(list);
1643 
1644 	rtnl_lock();
1645 	list_for_each_entry(net, net_list, exit_list)
1646 		ip6gre_destroy_tunnels(net, &list);
1647 	unregister_netdevice_many(&list);
1648 	rtnl_unlock();
1649 }
1650 
1651 static struct pernet_operations ip6gre_net_ops = {
1652 	.init = ip6gre_init_net,
1653 	.exit_batch = ip6gre_exit_batch_net,
1654 	.id   = &ip6gre_net_id,
1655 	.size = sizeof(struct ip6gre_net),
1656 };
1657 
1658 static int ip6gre_tunnel_validate(struct nlattr *tb[], struct nlattr *data[],
1659 				  struct netlink_ext_ack *extack)
1660 {
1661 	__be16 flags;
1662 
1663 	if (!data)
1664 		return 0;
1665 
1666 	flags = 0;
1667 	if (data[IFLA_GRE_IFLAGS])
1668 		flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]);
1669 	if (data[IFLA_GRE_OFLAGS])
1670 		flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]);
1671 	if (flags & (GRE_VERSION|GRE_ROUTING))
1672 		return -EINVAL;
1673 
1674 	return 0;
1675 }
1676 
1677 static int ip6gre_tap_validate(struct nlattr *tb[], struct nlattr *data[],
1678 			       struct netlink_ext_ack *extack)
1679 {
1680 	struct in6_addr daddr;
1681 
1682 	if (tb[IFLA_ADDRESS]) {
1683 		if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
1684 			return -EINVAL;
1685 		if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
1686 			return -EADDRNOTAVAIL;
1687 	}
1688 
1689 	if (!data)
1690 		goto out;
1691 
1692 	if (data[IFLA_GRE_REMOTE]) {
1693 		daddr = nla_get_in6_addr(data[IFLA_GRE_REMOTE]);
1694 		if (ipv6_addr_any(&daddr))
1695 			return -EINVAL;
1696 	}
1697 
1698 out:
1699 	return ip6gre_tunnel_validate(tb, data, extack);
1700 }
1701 
1702 static int ip6erspan_tap_validate(struct nlattr *tb[], struct nlattr *data[],
1703 				  struct netlink_ext_ack *extack)
1704 {
1705 	__be16 flags = 0;
1706 	int ret, ver = 0;
1707 
1708 	if (!data)
1709 		return 0;
1710 
1711 	ret = ip6gre_tap_validate(tb, data, extack);
1712 	if (ret)
1713 		return ret;
1714 
1715 	/* ERSPAN should only have GRE sequence and key flag */
1716 	if (data[IFLA_GRE_OFLAGS])
1717 		flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]);
1718 	if (data[IFLA_GRE_IFLAGS])
1719 		flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]);
1720 	if (!data[IFLA_GRE_COLLECT_METADATA] &&
1721 	    flags != (GRE_SEQ | GRE_KEY))
1722 		return -EINVAL;
1723 
1724 	/* ERSPAN Session ID only has 10-bit. Since we reuse
1725 	 * 32-bit key field as ID, check it's range.
1726 	 */
1727 	if (data[IFLA_GRE_IKEY] &&
1728 	    (ntohl(nla_get_be32(data[IFLA_GRE_IKEY])) & ~ID_MASK))
1729 		return -EINVAL;
1730 
1731 	if (data[IFLA_GRE_OKEY] &&
1732 	    (ntohl(nla_get_be32(data[IFLA_GRE_OKEY])) & ~ID_MASK))
1733 		return -EINVAL;
1734 
1735 	if (data[IFLA_GRE_ERSPAN_VER]) {
1736 		ver = nla_get_u8(data[IFLA_GRE_ERSPAN_VER]);
1737 		if (ver != 1 && ver != 2)
1738 			return -EINVAL;
1739 	}
1740 
1741 	if (ver == 1) {
1742 		if (data[IFLA_GRE_ERSPAN_INDEX]) {
1743 			u32 index = nla_get_u32(data[IFLA_GRE_ERSPAN_INDEX]);
1744 
1745 			if (index & ~INDEX_MASK)
1746 				return -EINVAL;
1747 		}
1748 	} else if (ver == 2) {
1749 		if (data[IFLA_GRE_ERSPAN_DIR]) {
1750 			u16 dir = nla_get_u8(data[IFLA_GRE_ERSPAN_DIR]);
1751 
1752 			if (dir & ~(DIR_MASK >> DIR_OFFSET))
1753 				return -EINVAL;
1754 		}
1755 
1756 		if (data[IFLA_GRE_ERSPAN_HWID]) {
1757 			u16 hwid = nla_get_u16(data[IFLA_GRE_ERSPAN_HWID]);
1758 
1759 			if (hwid & ~(HWID_MASK >> HWID_OFFSET))
1760 				return -EINVAL;
1761 		}
1762 	}
1763 
1764 	return 0;
1765 }
1766 
1767 static void ip6erspan_set_version(struct nlattr *data[],
1768 				  struct __ip6_tnl_parm *parms)
1769 {
1770 	if (!data)
1771 		return;
1772 
1773 	parms->erspan_ver = 1;
1774 	if (data[IFLA_GRE_ERSPAN_VER])
1775 		parms->erspan_ver = nla_get_u8(data[IFLA_GRE_ERSPAN_VER]);
1776 
1777 	if (parms->erspan_ver == 1) {
1778 		if (data[IFLA_GRE_ERSPAN_INDEX])
1779 			parms->index = nla_get_u32(data[IFLA_GRE_ERSPAN_INDEX]);
1780 	} else if (parms->erspan_ver == 2) {
1781 		if (data[IFLA_GRE_ERSPAN_DIR])
1782 			parms->dir = nla_get_u8(data[IFLA_GRE_ERSPAN_DIR]);
1783 		if (data[IFLA_GRE_ERSPAN_HWID])
1784 			parms->hwid = nla_get_u16(data[IFLA_GRE_ERSPAN_HWID]);
1785 	}
1786 }
1787 
1788 static void ip6gre_netlink_parms(struct nlattr *data[],
1789 				struct __ip6_tnl_parm *parms)
1790 {
1791 	memset(parms, 0, sizeof(*parms));
1792 
1793 	if (!data)
1794 		return;
1795 
1796 	if (data[IFLA_GRE_LINK])
1797 		parms->link = nla_get_u32(data[IFLA_GRE_LINK]);
1798 
1799 	if (data[IFLA_GRE_IFLAGS])
1800 		parms->i_flags = gre_flags_to_tnl_flags(
1801 				nla_get_be16(data[IFLA_GRE_IFLAGS]));
1802 
1803 	if (data[IFLA_GRE_OFLAGS])
1804 		parms->o_flags = gre_flags_to_tnl_flags(
1805 				nla_get_be16(data[IFLA_GRE_OFLAGS]));
1806 
1807 	if (data[IFLA_GRE_IKEY])
1808 		parms->i_key = nla_get_be32(data[IFLA_GRE_IKEY]);
1809 
1810 	if (data[IFLA_GRE_OKEY])
1811 		parms->o_key = nla_get_be32(data[IFLA_GRE_OKEY]);
1812 
1813 	if (data[IFLA_GRE_LOCAL])
1814 		parms->laddr = nla_get_in6_addr(data[IFLA_GRE_LOCAL]);
1815 
1816 	if (data[IFLA_GRE_REMOTE])
1817 		parms->raddr = nla_get_in6_addr(data[IFLA_GRE_REMOTE]);
1818 
1819 	if (data[IFLA_GRE_TTL])
1820 		parms->hop_limit = nla_get_u8(data[IFLA_GRE_TTL]);
1821 
1822 	if (data[IFLA_GRE_ENCAP_LIMIT])
1823 		parms->encap_limit = nla_get_u8(data[IFLA_GRE_ENCAP_LIMIT]);
1824 
1825 	if (data[IFLA_GRE_FLOWINFO])
1826 		parms->flowinfo = nla_get_be32(data[IFLA_GRE_FLOWINFO]);
1827 
1828 	if (data[IFLA_GRE_FLAGS])
1829 		parms->flags = nla_get_u32(data[IFLA_GRE_FLAGS]);
1830 
1831 	if (data[IFLA_GRE_FWMARK])
1832 		parms->fwmark = nla_get_u32(data[IFLA_GRE_FWMARK]);
1833 
1834 	if (data[IFLA_GRE_COLLECT_METADATA])
1835 		parms->collect_md = true;
1836 }
1837 
1838 static int ip6gre_tap_init(struct net_device *dev)
1839 {
1840 	int ret;
1841 
1842 	ret = ip6gre_tunnel_init_common(dev);
1843 	if (ret)
1844 		return ret;
1845 
1846 	dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1847 
1848 	return 0;
1849 }
1850 
1851 static const struct net_device_ops ip6gre_tap_netdev_ops = {
1852 	.ndo_init = ip6gre_tap_init,
1853 	.ndo_uninit = ip6gre_tunnel_uninit,
1854 	.ndo_start_xmit = ip6gre_tunnel_xmit,
1855 	.ndo_set_mac_address = eth_mac_addr,
1856 	.ndo_validate_addr = eth_validate_addr,
1857 	.ndo_change_mtu = ip6_tnl_change_mtu,
1858 	.ndo_get_stats64 = dev_get_tstats64,
1859 	.ndo_get_iflink = ip6_tnl_get_iflink,
1860 };
1861 
1862 static int ip6erspan_calc_hlen(struct ip6_tnl *tunnel)
1863 {
1864 	int t_hlen;
1865 
1866 	tunnel->tun_hlen = 8;
1867 	tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen +
1868 		       erspan_hdr_len(tunnel->parms.erspan_ver);
1869 
1870 	t_hlen = tunnel->hlen + sizeof(struct ipv6hdr);
1871 	tunnel->dev->needed_headroom = LL_MAX_HEADER + t_hlen;
1872 	return t_hlen;
1873 }
1874 
1875 static int ip6erspan_tap_init(struct net_device *dev)
1876 {
1877 	struct ip6_tnl *tunnel;
1878 	int t_hlen;
1879 	int ret;
1880 
1881 	tunnel = netdev_priv(dev);
1882 
1883 	tunnel->dev = dev;
1884 	tunnel->net = dev_net(dev);
1885 	strcpy(tunnel->parms.name, dev->name);
1886 
1887 	dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
1888 	if (!dev->tstats)
1889 		return -ENOMEM;
1890 
1891 	ret = dst_cache_init(&tunnel->dst_cache, GFP_KERNEL);
1892 	if (ret)
1893 		goto cleanup_alloc_pcpu_stats;
1894 
1895 	ret = gro_cells_init(&tunnel->gro_cells, dev);
1896 	if (ret)
1897 		goto cleanup_dst_cache_init;
1898 
1899 	t_hlen = ip6erspan_calc_hlen(tunnel);
1900 	dev->mtu = ETH_DATA_LEN - t_hlen;
1901 	if (dev->type == ARPHRD_ETHER)
1902 		dev->mtu -= ETH_HLEN;
1903 	if (!(tunnel->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1904 		dev->mtu -= 8;
1905 
1906 	dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1907 	ip6erspan_tnl_link_config(tunnel, 1);
1908 
1909 	netdev_hold(dev, &tunnel->dev_tracker, GFP_KERNEL);
1910 	netdev_lockdep_set_classes(dev);
1911 	return 0;
1912 
1913 cleanup_dst_cache_init:
1914 	dst_cache_destroy(&tunnel->dst_cache);
1915 cleanup_alloc_pcpu_stats:
1916 	free_percpu(dev->tstats);
1917 	dev->tstats = NULL;
1918 	return ret;
1919 }
1920 
1921 static const struct net_device_ops ip6erspan_netdev_ops = {
1922 	.ndo_init =		ip6erspan_tap_init,
1923 	.ndo_uninit =		ip6erspan_tunnel_uninit,
1924 	.ndo_start_xmit =	ip6erspan_tunnel_xmit,
1925 	.ndo_set_mac_address =	eth_mac_addr,
1926 	.ndo_validate_addr =	eth_validate_addr,
1927 	.ndo_change_mtu =	ip6_tnl_change_mtu,
1928 	.ndo_get_stats64 =	dev_get_tstats64,
1929 	.ndo_get_iflink =	ip6_tnl_get_iflink,
1930 };
1931 
1932 static void ip6gre_tap_setup(struct net_device *dev)
1933 {
1934 
1935 	ether_setup(dev);
1936 
1937 	dev->max_mtu = 0;
1938 	dev->netdev_ops = &ip6gre_tap_netdev_ops;
1939 	dev->needs_free_netdev = true;
1940 	dev->priv_destructor = ip6gre_dev_free;
1941 
1942 	dev->priv_flags &= ~IFF_TX_SKB_SHARING;
1943 	dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1944 	netif_keep_dst(dev);
1945 }
1946 
1947 static bool ip6gre_netlink_encap_parms(struct nlattr *data[],
1948 				       struct ip_tunnel_encap *ipencap)
1949 {
1950 	bool ret = false;
1951 
1952 	memset(ipencap, 0, sizeof(*ipencap));
1953 
1954 	if (!data)
1955 		return ret;
1956 
1957 	if (data[IFLA_GRE_ENCAP_TYPE]) {
1958 		ret = true;
1959 		ipencap->type = nla_get_u16(data[IFLA_GRE_ENCAP_TYPE]);
1960 	}
1961 
1962 	if (data[IFLA_GRE_ENCAP_FLAGS]) {
1963 		ret = true;
1964 		ipencap->flags = nla_get_u16(data[IFLA_GRE_ENCAP_FLAGS]);
1965 	}
1966 
1967 	if (data[IFLA_GRE_ENCAP_SPORT]) {
1968 		ret = true;
1969 		ipencap->sport = nla_get_be16(data[IFLA_GRE_ENCAP_SPORT]);
1970 	}
1971 
1972 	if (data[IFLA_GRE_ENCAP_DPORT]) {
1973 		ret = true;
1974 		ipencap->dport = nla_get_be16(data[IFLA_GRE_ENCAP_DPORT]);
1975 	}
1976 
1977 	return ret;
1978 }
1979 
1980 static int ip6gre_newlink_common(struct net *src_net, struct net_device *dev,
1981 				 struct nlattr *tb[], struct nlattr *data[],
1982 				 struct netlink_ext_ack *extack)
1983 {
1984 	struct ip6_tnl *nt;
1985 	struct ip_tunnel_encap ipencap;
1986 	int err;
1987 
1988 	nt = netdev_priv(dev);
1989 
1990 	if (ip6gre_netlink_encap_parms(data, &ipencap)) {
1991 		int err = ip6_tnl_encap_setup(nt, &ipencap);
1992 
1993 		if (err < 0)
1994 			return err;
1995 	}
1996 
1997 	if (dev->type == ARPHRD_ETHER && !tb[IFLA_ADDRESS])
1998 		eth_hw_addr_random(dev);
1999 
2000 	nt->dev = dev;
2001 	nt->net = dev_net(dev);
2002 
2003 	err = register_netdevice(dev);
2004 	if (err)
2005 		goto out;
2006 
2007 	if (tb[IFLA_MTU])
2008 		ip6_tnl_change_mtu(dev, nla_get_u32(tb[IFLA_MTU]));
2009 
2010 out:
2011 	return err;
2012 }
2013 
2014 static int ip6gre_newlink(struct net *src_net, struct net_device *dev,
2015 			  struct nlattr *tb[], struct nlattr *data[],
2016 			  struct netlink_ext_ack *extack)
2017 {
2018 	struct ip6_tnl *nt = netdev_priv(dev);
2019 	struct net *net = dev_net(dev);
2020 	struct ip6gre_net *ign;
2021 	int err;
2022 
2023 	ip6gre_netlink_parms(data, &nt->parms);
2024 	ign = net_generic(net, ip6gre_net_id);
2025 
2026 	if (nt->parms.collect_md) {
2027 		if (rtnl_dereference(ign->collect_md_tun))
2028 			return -EEXIST;
2029 	} else {
2030 		if (ip6gre_tunnel_find(net, &nt->parms, dev->type))
2031 			return -EEXIST;
2032 	}
2033 
2034 	err = ip6gre_newlink_common(src_net, dev, tb, data, extack);
2035 	if (!err) {
2036 		ip6gre_tnl_link_config(nt, !tb[IFLA_MTU]);
2037 		ip6gre_tunnel_link_md(ign, nt);
2038 		ip6gre_tunnel_link(net_generic(net, ip6gre_net_id), nt);
2039 	}
2040 	return err;
2041 }
2042 
2043 static struct ip6_tnl *
2044 ip6gre_changelink_common(struct net_device *dev, struct nlattr *tb[],
2045 			 struct nlattr *data[], struct __ip6_tnl_parm *p_p,
2046 			 struct netlink_ext_ack *extack)
2047 {
2048 	struct ip6_tnl *t, *nt = netdev_priv(dev);
2049 	struct net *net = nt->net;
2050 	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
2051 	struct ip_tunnel_encap ipencap;
2052 
2053 	if (dev == ign->fb_tunnel_dev)
2054 		return ERR_PTR(-EINVAL);
2055 
2056 	if (ip6gre_netlink_encap_parms(data, &ipencap)) {
2057 		int err = ip6_tnl_encap_setup(nt, &ipencap);
2058 
2059 		if (err < 0)
2060 			return ERR_PTR(err);
2061 	}
2062 
2063 	ip6gre_netlink_parms(data, p_p);
2064 
2065 	t = ip6gre_tunnel_locate(net, p_p, 0);
2066 
2067 	if (t) {
2068 		if (t->dev != dev)
2069 			return ERR_PTR(-EEXIST);
2070 	} else {
2071 		t = nt;
2072 	}
2073 
2074 	return t;
2075 }
2076 
2077 static int ip6gre_changelink(struct net_device *dev, struct nlattr *tb[],
2078 			     struct nlattr *data[],
2079 			     struct netlink_ext_ack *extack)
2080 {
2081 	struct ip6_tnl *t = netdev_priv(dev);
2082 	struct ip6gre_net *ign = net_generic(t->net, ip6gre_net_id);
2083 	struct __ip6_tnl_parm p;
2084 
2085 	t = ip6gre_changelink_common(dev, tb, data, &p, extack);
2086 	if (IS_ERR(t))
2087 		return PTR_ERR(t);
2088 
2089 	ip6gre_tunnel_unlink_md(ign, t);
2090 	ip6gre_tunnel_unlink(ign, t);
2091 	ip6gre_tnl_change(t, &p, !tb[IFLA_MTU]);
2092 	ip6gre_tunnel_link_md(ign, t);
2093 	ip6gre_tunnel_link(ign, t);
2094 	return 0;
2095 }
2096 
2097 static void ip6gre_dellink(struct net_device *dev, struct list_head *head)
2098 {
2099 	struct net *net = dev_net(dev);
2100 	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
2101 
2102 	if (dev != ign->fb_tunnel_dev)
2103 		unregister_netdevice_queue(dev, head);
2104 }
2105 
2106 static size_t ip6gre_get_size(const struct net_device *dev)
2107 {
2108 	return
2109 		/* IFLA_GRE_LINK */
2110 		nla_total_size(4) +
2111 		/* IFLA_GRE_IFLAGS */
2112 		nla_total_size(2) +
2113 		/* IFLA_GRE_OFLAGS */
2114 		nla_total_size(2) +
2115 		/* IFLA_GRE_IKEY */
2116 		nla_total_size(4) +
2117 		/* IFLA_GRE_OKEY */
2118 		nla_total_size(4) +
2119 		/* IFLA_GRE_LOCAL */
2120 		nla_total_size(sizeof(struct in6_addr)) +
2121 		/* IFLA_GRE_REMOTE */
2122 		nla_total_size(sizeof(struct in6_addr)) +
2123 		/* IFLA_GRE_TTL */
2124 		nla_total_size(1) +
2125 		/* IFLA_GRE_ENCAP_LIMIT */
2126 		nla_total_size(1) +
2127 		/* IFLA_GRE_FLOWINFO */
2128 		nla_total_size(4) +
2129 		/* IFLA_GRE_FLAGS */
2130 		nla_total_size(4) +
2131 		/* IFLA_GRE_ENCAP_TYPE */
2132 		nla_total_size(2) +
2133 		/* IFLA_GRE_ENCAP_FLAGS */
2134 		nla_total_size(2) +
2135 		/* IFLA_GRE_ENCAP_SPORT */
2136 		nla_total_size(2) +
2137 		/* IFLA_GRE_ENCAP_DPORT */
2138 		nla_total_size(2) +
2139 		/* IFLA_GRE_COLLECT_METADATA */
2140 		nla_total_size(0) +
2141 		/* IFLA_GRE_FWMARK */
2142 		nla_total_size(4) +
2143 		/* IFLA_GRE_ERSPAN_INDEX */
2144 		nla_total_size(4) +
2145 		0;
2146 }
2147 
2148 static int ip6gre_fill_info(struct sk_buff *skb, const struct net_device *dev)
2149 {
2150 	struct ip6_tnl *t = netdev_priv(dev);
2151 	struct __ip6_tnl_parm *p = &t->parms;
2152 	__be16 o_flags = p->o_flags;
2153 
2154 	if (p->erspan_ver == 1 || p->erspan_ver == 2) {
2155 		if (!p->collect_md)
2156 			o_flags |= TUNNEL_KEY;
2157 
2158 		if (nla_put_u8(skb, IFLA_GRE_ERSPAN_VER, p->erspan_ver))
2159 			goto nla_put_failure;
2160 
2161 		if (p->erspan_ver == 1) {
2162 			if (nla_put_u32(skb, IFLA_GRE_ERSPAN_INDEX, p->index))
2163 				goto nla_put_failure;
2164 		} else {
2165 			if (nla_put_u8(skb, IFLA_GRE_ERSPAN_DIR, p->dir))
2166 				goto nla_put_failure;
2167 			if (nla_put_u16(skb, IFLA_GRE_ERSPAN_HWID, p->hwid))
2168 				goto nla_put_failure;
2169 		}
2170 	}
2171 
2172 	if (nla_put_u32(skb, IFLA_GRE_LINK, p->link) ||
2173 	    nla_put_be16(skb, IFLA_GRE_IFLAGS,
2174 			 gre_tnl_flags_to_gre_flags(p->i_flags)) ||
2175 	    nla_put_be16(skb, IFLA_GRE_OFLAGS,
2176 			 gre_tnl_flags_to_gre_flags(o_flags)) ||
2177 	    nla_put_be32(skb, IFLA_GRE_IKEY, p->i_key) ||
2178 	    nla_put_be32(skb, IFLA_GRE_OKEY, p->o_key) ||
2179 	    nla_put_in6_addr(skb, IFLA_GRE_LOCAL, &p->laddr) ||
2180 	    nla_put_in6_addr(skb, IFLA_GRE_REMOTE, &p->raddr) ||
2181 	    nla_put_u8(skb, IFLA_GRE_TTL, p->hop_limit) ||
2182 	    nla_put_u8(skb, IFLA_GRE_ENCAP_LIMIT, p->encap_limit) ||
2183 	    nla_put_be32(skb, IFLA_GRE_FLOWINFO, p->flowinfo) ||
2184 	    nla_put_u32(skb, IFLA_GRE_FLAGS, p->flags) ||
2185 	    nla_put_u32(skb, IFLA_GRE_FWMARK, p->fwmark))
2186 		goto nla_put_failure;
2187 
2188 	if (nla_put_u16(skb, IFLA_GRE_ENCAP_TYPE,
2189 			t->encap.type) ||
2190 	    nla_put_be16(skb, IFLA_GRE_ENCAP_SPORT,
2191 			 t->encap.sport) ||
2192 	    nla_put_be16(skb, IFLA_GRE_ENCAP_DPORT,
2193 			 t->encap.dport) ||
2194 	    nla_put_u16(skb, IFLA_GRE_ENCAP_FLAGS,
2195 			t->encap.flags))
2196 		goto nla_put_failure;
2197 
2198 	if (p->collect_md) {
2199 		if (nla_put_flag(skb, IFLA_GRE_COLLECT_METADATA))
2200 			goto nla_put_failure;
2201 	}
2202 
2203 	return 0;
2204 
2205 nla_put_failure:
2206 	return -EMSGSIZE;
2207 }
2208 
2209 static const struct nla_policy ip6gre_policy[IFLA_GRE_MAX + 1] = {
2210 	[IFLA_GRE_LINK]        = { .type = NLA_U32 },
2211 	[IFLA_GRE_IFLAGS]      = { .type = NLA_U16 },
2212 	[IFLA_GRE_OFLAGS]      = { .type = NLA_U16 },
2213 	[IFLA_GRE_IKEY]        = { .type = NLA_U32 },
2214 	[IFLA_GRE_OKEY]        = { .type = NLA_U32 },
2215 	[IFLA_GRE_LOCAL]       = { .len = sizeof_field(struct ipv6hdr, saddr) },
2216 	[IFLA_GRE_REMOTE]      = { .len = sizeof_field(struct ipv6hdr, daddr) },
2217 	[IFLA_GRE_TTL]         = { .type = NLA_U8 },
2218 	[IFLA_GRE_ENCAP_LIMIT] = { .type = NLA_U8 },
2219 	[IFLA_GRE_FLOWINFO]    = { .type = NLA_U32 },
2220 	[IFLA_GRE_FLAGS]       = { .type = NLA_U32 },
2221 	[IFLA_GRE_ENCAP_TYPE]   = { .type = NLA_U16 },
2222 	[IFLA_GRE_ENCAP_FLAGS]  = { .type = NLA_U16 },
2223 	[IFLA_GRE_ENCAP_SPORT]  = { .type = NLA_U16 },
2224 	[IFLA_GRE_ENCAP_DPORT]  = { .type = NLA_U16 },
2225 	[IFLA_GRE_COLLECT_METADATA] = { .type = NLA_FLAG },
2226 	[IFLA_GRE_FWMARK]       = { .type = NLA_U32 },
2227 	[IFLA_GRE_ERSPAN_INDEX] = { .type = NLA_U32 },
2228 	[IFLA_GRE_ERSPAN_VER]	= { .type = NLA_U8 },
2229 	[IFLA_GRE_ERSPAN_DIR]	= { .type = NLA_U8 },
2230 	[IFLA_GRE_ERSPAN_HWID]	= { .type = NLA_U16 },
2231 };
2232 
2233 static void ip6erspan_tap_setup(struct net_device *dev)
2234 {
2235 	ether_setup(dev);
2236 
2237 	dev->max_mtu = 0;
2238 	dev->netdev_ops = &ip6erspan_netdev_ops;
2239 	dev->needs_free_netdev = true;
2240 	dev->priv_destructor = ip6gre_dev_free;
2241 
2242 	dev->priv_flags &= ~IFF_TX_SKB_SHARING;
2243 	dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
2244 	netif_keep_dst(dev);
2245 }
2246 
2247 static int ip6erspan_newlink(struct net *src_net, struct net_device *dev,
2248 			     struct nlattr *tb[], struct nlattr *data[],
2249 			     struct netlink_ext_ack *extack)
2250 {
2251 	struct ip6_tnl *nt = netdev_priv(dev);
2252 	struct net *net = dev_net(dev);
2253 	struct ip6gre_net *ign;
2254 	int err;
2255 
2256 	ip6gre_netlink_parms(data, &nt->parms);
2257 	ip6erspan_set_version(data, &nt->parms);
2258 	ign = net_generic(net, ip6gre_net_id);
2259 
2260 	if (nt->parms.collect_md) {
2261 		if (rtnl_dereference(ign->collect_md_tun_erspan))
2262 			return -EEXIST;
2263 	} else {
2264 		if (ip6gre_tunnel_find(net, &nt->parms, dev->type))
2265 			return -EEXIST;
2266 	}
2267 
2268 	err = ip6gre_newlink_common(src_net, dev, tb, data, extack);
2269 	if (!err) {
2270 		ip6erspan_tnl_link_config(nt, !tb[IFLA_MTU]);
2271 		ip6erspan_tunnel_link_md(ign, nt);
2272 		ip6gre_tunnel_link(net_generic(net, ip6gre_net_id), nt);
2273 	}
2274 	return err;
2275 }
2276 
2277 static void ip6erspan_tnl_link_config(struct ip6_tnl *t, int set_mtu)
2278 {
2279 	ip6gre_tnl_link_config_common(t);
2280 	ip6gre_tnl_link_config_route(t, set_mtu, ip6erspan_calc_hlen(t));
2281 }
2282 
2283 static int ip6erspan_tnl_change(struct ip6_tnl *t,
2284 				const struct __ip6_tnl_parm *p, int set_mtu)
2285 {
2286 	ip6gre_tnl_copy_tnl_parm(t, p);
2287 	ip6erspan_tnl_link_config(t, set_mtu);
2288 	return 0;
2289 }
2290 
2291 static int ip6erspan_changelink(struct net_device *dev, struct nlattr *tb[],
2292 				struct nlattr *data[],
2293 				struct netlink_ext_ack *extack)
2294 {
2295 	struct ip6gre_net *ign = net_generic(dev_net(dev), ip6gre_net_id);
2296 	struct __ip6_tnl_parm p;
2297 	struct ip6_tnl *t;
2298 
2299 	t = ip6gre_changelink_common(dev, tb, data, &p, extack);
2300 	if (IS_ERR(t))
2301 		return PTR_ERR(t);
2302 
2303 	ip6erspan_set_version(data, &p);
2304 	ip6gre_tunnel_unlink_md(ign, t);
2305 	ip6gre_tunnel_unlink(ign, t);
2306 	ip6erspan_tnl_change(t, &p, !tb[IFLA_MTU]);
2307 	ip6erspan_tunnel_link_md(ign, t);
2308 	ip6gre_tunnel_link(ign, t);
2309 	return 0;
2310 }
2311 
2312 static struct rtnl_link_ops ip6gre_link_ops __read_mostly = {
2313 	.kind		= "ip6gre",
2314 	.maxtype	= IFLA_GRE_MAX,
2315 	.policy		= ip6gre_policy,
2316 	.priv_size	= sizeof(struct ip6_tnl),
2317 	.setup		= ip6gre_tunnel_setup,
2318 	.validate	= ip6gre_tunnel_validate,
2319 	.newlink	= ip6gre_newlink,
2320 	.changelink	= ip6gre_changelink,
2321 	.dellink	= ip6gre_dellink,
2322 	.get_size	= ip6gre_get_size,
2323 	.fill_info	= ip6gre_fill_info,
2324 	.get_link_net	= ip6_tnl_get_link_net,
2325 };
2326 
2327 static struct rtnl_link_ops ip6gre_tap_ops __read_mostly = {
2328 	.kind		= "ip6gretap",
2329 	.maxtype	= IFLA_GRE_MAX,
2330 	.policy		= ip6gre_policy,
2331 	.priv_size	= sizeof(struct ip6_tnl),
2332 	.setup		= ip6gre_tap_setup,
2333 	.validate	= ip6gre_tap_validate,
2334 	.newlink	= ip6gre_newlink,
2335 	.changelink	= ip6gre_changelink,
2336 	.get_size	= ip6gre_get_size,
2337 	.fill_info	= ip6gre_fill_info,
2338 	.get_link_net	= ip6_tnl_get_link_net,
2339 };
2340 
2341 static struct rtnl_link_ops ip6erspan_tap_ops __read_mostly = {
2342 	.kind		= "ip6erspan",
2343 	.maxtype	= IFLA_GRE_MAX,
2344 	.policy		= ip6gre_policy,
2345 	.priv_size	= sizeof(struct ip6_tnl),
2346 	.setup		= ip6erspan_tap_setup,
2347 	.validate	= ip6erspan_tap_validate,
2348 	.newlink	= ip6erspan_newlink,
2349 	.changelink	= ip6erspan_changelink,
2350 	.get_size	= ip6gre_get_size,
2351 	.fill_info	= ip6gre_fill_info,
2352 	.get_link_net	= ip6_tnl_get_link_net,
2353 };
2354 
2355 /*
2356  *	And now the modules code and kernel interface.
2357  */
2358 
2359 static int __init ip6gre_init(void)
2360 {
2361 	int err;
2362 
2363 	pr_info("GRE over IPv6 tunneling driver\n");
2364 
2365 	err = register_pernet_device(&ip6gre_net_ops);
2366 	if (err < 0)
2367 		return err;
2368 
2369 	err = inet6_add_protocol(&ip6gre_protocol, IPPROTO_GRE);
2370 	if (err < 0) {
2371 		pr_info("%s: can't add protocol\n", __func__);
2372 		goto add_proto_failed;
2373 	}
2374 
2375 	err = rtnl_link_register(&ip6gre_link_ops);
2376 	if (err < 0)
2377 		goto rtnl_link_failed;
2378 
2379 	err = rtnl_link_register(&ip6gre_tap_ops);
2380 	if (err < 0)
2381 		goto tap_ops_failed;
2382 
2383 	err = rtnl_link_register(&ip6erspan_tap_ops);
2384 	if (err < 0)
2385 		goto erspan_link_failed;
2386 
2387 out:
2388 	return err;
2389 
2390 erspan_link_failed:
2391 	rtnl_link_unregister(&ip6gre_tap_ops);
2392 tap_ops_failed:
2393 	rtnl_link_unregister(&ip6gre_link_ops);
2394 rtnl_link_failed:
2395 	inet6_del_protocol(&ip6gre_protocol, IPPROTO_GRE);
2396 add_proto_failed:
2397 	unregister_pernet_device(&ip6gre_net_ops);
2398 	goto out;
2399 }
2400 
2401 static void __exit ip6gre_fini(void)
2402 {
2403 	rtnl_link_unregister(&ip6gre_tap_ops);
2404 	rtnl_link_unregister(&ip6gre_link_ops);
2405 	rtnl_link_unregister(&ip6erspan_tap_ops);
2406 	inet6_del_protocol(&ip6gre_protocol, IPPROTO_GRE);
2407 	unregister_pernet_device(&ip6gre_net_ops);
2408 }
2409 
2410 module_init(ip6gre_init);
2411 module_exit(ip6gre_fini);
2412 MODULE_LICENSE("GPL");
2413 MODULE_AUTHOR("D. Kozlov (xeb@mail.ru)");
2414 MODULE_DESCRIPTION("GRE over IPv6 tunneling device");
2415 MODULE_ALIAS_RTNL_LINK("ip6gre");
2416 MODULE_ALIAS_RTNL_LINK("ip6gretap");
2417 MODULE_ALIAS_RTNL_LINK("ip6erspan");
2418 MODULE_ALIAS_NETDEV("ip6gre0");
2419