xref: /openbmc/linux/net/ipv6/ip6_gre.c (revision 04dc82e1)
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 
131 	for_each_ip_tunnel_rcu(t, ign->tunnels_r_l[h0 ^ h1]) {
132 		if (!ipv6_addr_equal(local, &t->parms.laddr) ||
133 		    !ipv6_addr_equal(remote, &t->parms.raddr) ||
134 		    key != t->parms.i_key ||
135 		    !(t->dev->flags & IFF_UP))
136 			continue;
137 
138 		if (t->dev->type != ARPHRD_IP6GRE &&
139 		    t->dev->type != dev_type)
140 			continue;
141 
142 		score = 0;
143 		if (t->parms.link != link)
144 			score |= 1;
145 		if (t->dev->type != dev_type)
146 			score |= 2;
147 		if (score == 0)
148 			return t;
149 
150 		if (score < cand_score) {
151 			cand = t;
152 			cand_score = score;
153 		}
154 	}
155 
156 	for_each_ip_tunnel_rcu(t, ign->tunnels_r[h0 ^ h1]) {
157 		if (!ipv6_addr_equal(remote, &t->parms.raddr) ||
158 		    key != t->parms.i_key ||
159 		    !(t->dev->flags & IFF_UP))
160 			continue;
161 
162 		if (t->dev->type != ARPHRD_IP6GRE &&
163 		    t->dev->type != dev_type)
164 			continue;
165 
166 		score = 0;
167 		if (t->parms.link != link)
168 			score |= 1;
169 		if (t->dev->type != dev_type)
170 			score |= 2;
171 		if (score == 0)
172 			return t;
173 
174 		if (score < cand_score) {
175 			cand = t;
176 			cand_score = score;
177 		}
178 	}
179 
180 	for_each_ip_tunnel_rcu(t, ign->tunnels_l[h1]) {
181 		if ((!ipv6_addr_equal(local, &t->parms.laddr) &&
182 			  (!ipv6_addr_equal(local, &t->parms.raddr) ||
183 				 !ipv6_addr_is_multicast(local))) ||
184 		    key != t->parms.i_key ||
185 		    !(t->dev->flags & IFF_UP))
186 			continue;
187 
188 		if (t->dev->type != ARPHRD_IP6GRE &&
189 		    t->dev->type != dev_type)
190 			continue;
191 
192 		score = 0;
193 		if (t->parms.link != link)
194 			score |= 1;
195 		if (t->dev->type != dev_type)
196 			score |= 2;
197 		if (score == 0)
198 			return t;
199 
200 		if (score < cand_score) {
201 			cand = t;
202 			cand_score = score;
203 		}
204 	}
205 
206 	for_each_ip_tunnel_rcu(t, ign->tunnels_wc[h1]) {
207 		if (t->parms.i_key != key ||
208 		    !(t->dev->flags & IFF_UP))
209 			continue;
210 
211 		if (t->dev->type != ARPHRD_IP6GRE &&
212 		    t->dev->type != dev_type)
213 			continue;
214 
215 		score = 0;
216 		if (t->parms.link != link)
217 			score |= 1;
218 		if (t->dev->type != dev_type)
219 			score |= 2;
220 		if (score == 0)
221 			return t;
222 
223 		if (score < cand_score) {
224 			cand = t;
225 			cand_score = score;
226 		}
227 	}
228 
229 	if (cand)
230 		return cand;
231 
232 	if (gre_proto == htons(ETH_P_ERSPAN) ||
233 	    gre_proto == htons(ETH_P_ERSPAN2))
234 		t = rcu_dereference(ign->collect_md_tun_erspan);
235 	else
236 		t = rcu_dereference(ign->collect_md_tun);
237 
238 	if (t && t->dev->flags & IFF_UP)
239 		return t;
240 
241 	dev = ign->fb_tunnel_dev;
242 	if (dev && dev->flags & IFF_UP)
243 		return netdev_priv(dev);
244 
245 	return NULL;
246 }
247 
248 static struct ip6_tnl __rcu **__ip6gre_bucket(struct ip6gre_net *ign,
249 		const struct __ip6_tnl_parm *p)
250 {
251 	const struct in6_addr *remote = &p->raddr;
252 	const struct in6_addr *local = &p->laddr;
253 	unsigned int h = HASH_KEY(p->i_key);
254 	int prio = 0;
255 
256 	if (!ipv6_addr_any(local))
257 		prio |= 1;
258 	if (!ipv6_addr_any(remote) && !ipv6_addr_is_multicast(remote)) {
259 		prio |= 2;
260 		h ^= HASH_ADDR(remote);
261 	}
262 
263 	return &ign->tunnels[prio][h];
264 }
265 
266 static void ip6gre_tunnel_link_md(struct ip6gre_net *ign, struct ip6_tnl *t)
267 {
268 	if (t->parms.collect_md)
269 		rcu_assign_pointer(ign->collect_md_tun, t);
270 }
271 
272 static void ip6erspan_tunnel_link_md(struct ip6gre_net *ign, struct ip6_tnl *t)
273 {
274 	if (t->parms.collect_md)
275 		rcu_assign_pointer(ign->collect_md_tun_erspan, t);
276 }
277 
278 static void ip6gre_tunnel_unlink_md(struct ip6gre_net *ign, struct ip6_tnl *t)
279 {
280 	if (t->parms.collect_md)
281 		rcu_assign_pointer(ign->collect_md_tun, NULL);
282 }
283 
284 static void ip6erspan_tunnel_unlink_md(struct ip6gre_net *ign,
285 				       struct ip6_tnl *t)
286 {
287 	if (t->parms.collect_md)
288 		rcu_assign_pointer(ign->collect_md_tun_erspan, NULL);
289 }
290 
291 static inline struct ip6_tnl __rcu **ip6gre_bucket(struct ip6gre_net *ign,
292 		const struct ip6_tnl *t)
293 {
294 	return __ip6gre_bucket(ign, &t->parms);
295 }
296 
297 static void ip6gre_tunnel_link(struct ip6gre_net *ign, struct ip6_tnl *t)
298 {
299 	struct ip6_tnl __rcu **tp = ip6gre_bucket(ign, t);
300 
301 	rcu_assign_pointer(t->next, rtnl_dereference(*tp));
302 	rcu_assign_pointer(*tp, t);
303 }
304 
305 static void ip6gre_tunnel_unlink(struct ip6gre_net *ign, struct ip6_tnl *t)
306 {
307 	struct ip6_tnl __rcu **tp;
308 	struct ip6_tnl *iter;
309 
310 	for (tp = ip6gre_bucket(ign, t);
311 	     (iter = rtnl_dereference(*tp)) != NULL;
312 	     tp = &iter->next) {
313 		if (t == iter) {
314 			rcu_assign_pointer(*tp, t->next);
315 			break;
316 		}
317 	}
318 }
319 
320 static struct ip6_tnl *ip6gre_tunnel_find(struct net *net,
321 					   const struct __ip6_tnl_parm *parms,
322 					   int type)
323 {
324 	const struct in6_addr *remote = &parms->raddr;
325 	const struct in6_addr *local = &parms->laddr;
326 	__be32 key = parms->i_key;
327 	int link = parms->link;
328 	struct ip6_tnl *t;
329 	struct ip6_tnl __rcu **tp;
330 	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
331 
332 	for (tp = __ip6gre_bucket(ign, parms);
333 	     (t = rtnl_dereference(*tp)) != NULL;
334 	     tp = &t->next)
335 		if (ipv6_addr_equal(local, &t->parms.laddr) &&
336 		    ipv6_addr_equal(remote, &t->parms.raddr) &&
337 		    key == t->parms.i_key &&
338 		    link == t->parms.link &&
339 		    type == t->dev->type)
340 			break;
341 
342 	return t;
343 }
344 
345 static struct ip6_tnl *ip6gre_tunnel_locate(struct net *net,
346 		const struct __ip6_tnl_parm *parms, int create)
347 {
348 	struct ip6_tnl *t, *nt;
349 	struct net_device *dev;
350 	char name[IFNAMSIZ];
351 	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
352 
353 	t = ip6gre_tunnel_find(net, parms, ARPHRD_IP6GRE);
354 	if (t && create)
355 		return NULL;
356 	if (t || !create)
357 		return t;
358 
359 	if (parms->name[0]) {
360 		if (!dev_valid_name(parms->name))
361 			return NULL;
362 		strlcpy(name, parms->name, IFNAMSIZ);
363 	} else {
364 		strcpy(name, "ip6gre%d");
365 	}
366 	dev = alloc_netdev(sizeof(*t), name, NET_NAME_UNKNOWN,
367 			   ip6gre_tunnel_setup);
368 	if (!dev)
369 		return NULL;
370 
371 	dev_net_set(dev, net);
372 
373 	nt = netdev_priv(dev);
374 	nt->parms = *parms;
375 	dev->rtnl_link_ops = &ip6gre_link_ops;
376 
377 	nt->dev = dev;
378 	nt->net = dev_net(dev);
379 
380 	if (register_netdevice(dev) < 0)
381 		goto failed_free;
382 
383 	ip6gre_tnl_link_config(nt, 1);
384 
385 	/* Can use a lockless transmit, unless we generate output sequences */
386 	if (!(nt->parms.o_flags & TUNNEL_SEQ))
387 		dev->features |= NETIF_F_LLTX;
388 
389 	dev_hold(dev);
390 	ip6gre_tunnel_link(ign, nt);
391 	return nt;
392 
393 failed_free:
394 	free_netdev(dev);
395 	return NULL;
396 }
397 
398 static void ip6erspan_tunnel_uninit(struct net_device *dev)
399 {
400 	struct ip6_tnl *t = netdev_priv(dev);
401 	struct ip6gre_net *ign = net_generic(t->net, ip6gre_net_id);
402 
403 	ip6erspan_tunnel_unlink_md(ign, t);
404 	ip6gre_tunnel_unlink(ign, t);
405 	dst_cache_reset(&t->dst_cache);
406 	dev_put(dev);
407 }
408 
409 static void ip6gre_tunnel_uninit(struct net_device *dev)
410 {
411 	struct ip6_tnl *t = netdev_priv(dev);
412 	struct ip6gre_net *ign = net_generic(t->net, ip6gre_net_id);
413 
414 	ip6gre_tunnel_unlink_md(ign, t);
415 	ip6gre_tunnel_unlink(ign, t);
416 	dst_cache_reset(&t->dst_cache);
417 	dev_put(dev);
418 }
419 
420 
421 static int ip6gre_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
422 		       u8 type, u8 code, int offset, __be32 info)
423 {
424 	struct net *net = dev_net(skb->dev);
425 	const struct ipv6hdr *ipv6h;
426 	struct tnl_ptk_info tpi;
427 	struct ip6_tnl *t;
428 
429 	if (gre_parse_header(skb, &tpi, NULL, htons(ETH_P_IPV6),
430 			     offset) < 0)
431 		return -EINVAL;
432 
433 	ipv6h = (const struct ipv6hdr *)skb->data;
434 	t = ip6gre_tunnel_lookup(skb->dev, &ipv6h->daddr, &ipv6h->saddr,
435 				 tpi.key, tpi.proto);
436 	if (!t)
437 		return -ENOENT;
438 
439 	switch (type) {
440 		struct ipv6_tlv_tnl_enc_lim *tel;
441 		__u32 teli;
442 	case ICMPV6_DEST_UNREACH:
443 		net_dbg_ratelimited("%s: Path to destination invalid or inactive!\n",
444 				    t->parms.name);
445 		if (code != ICMPV6_PORT_UNREACH)
446 			break;
447 		return 0;
448 	case ICMPV6_TIME_EXCEED:
449 		if (code == ICMPV6_EXC_HOPLIMIT) {
450 			net_dbg_ratelimited("%s: Too small hop limit or routing loop in tunnel!\n",
451 					    t->parms.name);
452 			break;
453 		}
454 		return 0;
455 	case ICMPV6_PARAMPROB:
456 		teli = 0;
457 		if (code == ICMPV6_HDR_FIELD)
458 			teli = ip6_tnl_parse_tlv_enc_lim(skb, skb->data);
459 
460 		if (teli && teli == be32_to_cpu(info) - 2) {
461 			tel = (struct ipv6_tlv_tnl_enc_lim *) &skb->data[teli];
462 			if (tel->encap_limit == 0) {
463 				net_dbg_ratelimited("%s: Too small encapsulation limit or routing loop in tunnel!\n",
464 						    t->parms.name);
465 			}
466 		} else {
467 			net_dbg_ratelimited("%s: Recipient unable to parse tunneled packet!\n",
468 					    t->parms.name);
469 		}
470 		return 0;
471 	case ICMPV6_PKT_TOOBIG:
472 		ip6_update_pmtu(skb, net, info, 0, 0, sock_net_uid(net, NULL));
473 		return 0;
474 	case NDISC_REDIRECT:
475 		ip6_redirect(skb, net, skb->dev->ifindex, 0,
476 			     sock_net_uid(net, NULL));
477 		return 0;
478 	}
479 
480 	if (time_before(jiffies, t->err_time + IP6TUNNEL_ERR_TIMEO))
481 		t->err_count++;
482 	else
483 		t->err_count = 1;
484 	t->err_time = jiffies;
485 
486 	return 0;
487 }
488 
489 static int ip6gre_rcv(struct sk_buff *skb, const struct tnl_ptk_info *tpi)
490 {
491 	const struct ipv6hdr *ipv6h;
492 	struct ip6_tnl *tunnel;
493 
494 	ipv6h = ipv6_hdr(skb);
495 	tunnel = ip6gre_tunnel_lookup(skb->dev,
496 				      &ipv6h->saddr, &ipv6h->daddr, tpi->key,
497 				      tpi->proto);
498 	if (tunnel) {
499 		if (tunnel->parms.collect_md) {
500 			struct metadata_dst *tun_dst;
501 			__be64 tun_id;
502 			__be16 flags;
503 
504 			flags = tpi->flags;
505 			tun_id = key32_to_tunnel_id(tpi->key);
506 
507 			tun_dst = ipv6_tun_rx_dst(skb, flags, tun_id, 0);
508 			if (!tun_dst)
509 				return PACKET_REJECT;
510 
511 			ip6_tnl_rcv(tunnel, skb, tpi, tun_dst, log_ecn_error);
512 		} else {
513 			ip6_tnl_rcv(tunnel, skb, tpi, NULL, log_ecn_error);
514 		}
515 
516 		return PACKET_RCVD;
517 	}
518 
519 	return PACKET_REJECT;
520 }
521 
522 static int ip6erspan_rcv(struct sk_buff *skb,
523 			 struct tnl_ptk_info *tpi,
524 			 int gre_hdr_len)
525 {
526 	struct erspan_base_hdr *ershdr;
527 	const struct ipv6hdr *ipv6h;
528 	struct erspan_md2 *md2;
529 	struct ip6_tnl *tunnel;
530 	u8 ver;
531 
532 	ipv6h = ipv6_hdr(skb);
533 	ershdr = (struct erspan_base_hdr *)skb->data;
534 	ver = ershdr->ver;
535 
536 	tunnel = ip6gre_tunnel_lookup(skb->dev,
537 				      &ipv6h->saddr, &ipv6h->daddr, tpi->key,
538 				      tpi->proto);
539 	if (tunnel) {
540 		int len = erspan_hdr_len(ver);
541 
542 		if (unlikely(!pskb_may_pull(skb, len)))
543 			return PACKET_REJECT;
544 
545 		if (__iptunnel_pull_header(skb, len,
546 					   htons(ETH_P_TEB),
547 					   false, false) < 0)
548 			return PACKET_REJECT;
549 
550 		if (tunnel->parms.collect_md) {
551 			struct erspan_metadata *pkt_md, *md;
552 			struct metadata_dst *tun_dst;
553 			struct ip_tunnel_info *info;
554 			unsigned char *gh;
555 			__be64 tun_id;
556 			__be16 flags;
557 
558 			tpi->flags |= TUNNEL_KEY;
559 			flags = tpi->flags;
560 			tun_id = key32_to_tunnel_id(tpi->key);
561 
562 			tun_dst = ipv6_tun_rx_dst(skb, flags, tun_id,
563 						  sizeof(*md));
564 			if (!tun_dst)
565 				return PACKET_REJECT;
566 
567 			/* skb can be uncloned in __iptunnel_pull_header, so
568 			 * old pkt_md is no longer valid and we need to reset
569 			 * it
570 			 */
571 			gh = skb_network_header(skb) +
572 			     skb_network_header_len(skb);
573 			pkt_md = (struct erspan_metadata *)(gh + gre_hdr_len +
574 							    sizeof(*ershdr));
575 			info = &tun_dst->u.tun_info;
576 			md = ip_tunnel_info_opts(info);
577 			md->version = ver;
578 			md2 = &md->u.md2;
579 			memcpy(md2, pkt_md, ver == 1 ? ERSPAN_V1_MDSIZE :
580 						       ERSPAN_V2_MDSIZE);
581 			info->key.tun_flags |= TUNNEL_ERSPAN_OPT;
582 			info->options_len = sizeof(*md);
583 
584 			ip6_tnl_rcv(tunnel, skb, tpi, tun_dst, log_ecn_error);
585 
586 		} else {
587 			ip6_tnl_rcv(tunnel, skb, tpi, NULL, log_ecn_error);
588 		}
589 
590 		return PACKET_RCVD;
591 	}
592 
593 	return PACKET_REJECT;
594 }
595 
596 static int gre_rcv(struct sk_buff *skb)
597 {
598 	struct tnl_ptk_info tpi;
599 	bool csum_err = false;
600 	int hdr_len;
601 
602 	hdr_len = gre_parse_header(skb, &tpi, &csum_err, htons(ETH_P_IPV6), 0);
603 	if (hdr_len < 0)
604 		goto drop;
605 
606 	if (iptunnel_pull_header(skb, hdr_len, tpi.proto, false))
607 		goto drop;
608 
609 	if (unlikely(tpi.proto == htons(ETH_P_ERSPAN) ||
610 		     tpi.proto == htons(ETH_P_ERSPAN2))) {
611 		if (ip6erspan_rcv(skb, &tpi, hdr_len) == PACKET_RCVD)
612 			return 0;
613 		goto out;
614 	}
615 
616 	if (ip6gre_rcv(skb, &tpi) == PACKET_RCVD)
617 		return 0;
618 
619 out:
620 	icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0);
621 drop:
622 	kfree_skb(skb);
623 	return 0;
624 }
625 
626 static int gre_handle_offloads(struct sk_buff *skb, bool csum)
627 {
628 	return iptunnel_handle_offloads(skb,
629 					csum ? SKB_GSO_GRE_CSUM : SKB_GSO_GRE);
630 }
631 
632 static void prepare_ip6gre_xmit_ipv4(struct sk_buff *skb,
633 				     struct net_device *dev,
634 				     struct flowi6 *fl6, __u8 *dsfield,
635 				     int *encap_limit)
636 {
637 	const struct iphdr *iph = ip_hdr(skb);
638 	struct ip6_tnl *t = netdev_priv(dev);
639 
640 	if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
641 		*encap_limit = t->parms.encap_limit;
642 
643 	memcpy(fl6, &t->fl.u.ip6, sizeof(*fl6));
644 
645 	if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
646 		*dsfield = ipv4_get_dsfield(iph);
647 	else
648 		*dsfield = ip6_tclass(t->parms.flowinfo);
649 
650 	if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
651 		fl6->flowi6_mark = skb->mark;
652 	else
653 		fl6->flowi6_mark = t->parms.fwmark;
654 
655 	fl6->flowi6_uid = sock_net_uid(dev_net(dev), NULL);
656 }
657 
658 static int prepare_ip6gre_xmit_ipv6(struct sk_buff *skb,
659 				    struct net_device *dev,
660 				    struct flowi6 *fl6, __u8 *dsfield,
661 				    int *encap_limit)
662 {
663 	struct ipv6hdr *ipv6h = ipv6_hdr(skb);
664 	struct ip6_tnl *t = netdev_priv(dev);
665 	__u16 offset;
666 
667 	offset = ip6_tnl_parse_tlv_enc_lim(skb, skb_network_header(skb));
668 	/* ip6_tnl_parse_tlv_enc_lim() might have reallocated skb->head */
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_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 netdev_tx_t __gre6_xmit(struct sk_buff *skb,
705 			       struct net_device *dev, __u8 dsfield,
706 			       struct flowi6 *fl6, int encap_limit,
707 			       __u32 *pmtu, __be16 proto)
708 {
709 	struct ip6_tnl *tunnel = netdev_priv(dev);
710 	__be16 protocol;
711 
712 	if (dev->type == ARPHRD_ETHER)
713 		IPCB(skb)->flags = 0;
714 
715 	if (dev->header_ops && dev->type == ARPHRD_IP6GRE)
716 		fl6->daddr = ((struct ipv6hdr *)skb->data)->daddr;
717 	else
718 		fl6->daddr = tunnel->parms.raddr;
719 
720 	if (skb_cow_head(skb, dev->needed_headroom ?: tunnel->hlen))
721 		return -ENOMEM;
722 
723 	/* Push GRE header. */
724 	protocol = (dev->type == ARPHRD_ETHER) ? htons(ETH_P_TEB) : proto;
725 
726 	if (tunnel->parms.collect_md) {
727 		struct ip_tunnel_info *tun_info;
728 		const struct ip_tunnel_key *key;
729 		__be16 flags;
730 
731 		tun_info = skb_tunnel_info(skb);
732 		if (unlikely(!tun_info ||
733 			     !(tun_info->mode & IP_TUNNEL_INFO_TX) ||
734 			     ip_tunnel_info_af(tun_info) != AF_INET6))
735 			return -EINVAL;
736 
737 		key = &tun_info->key;
738 		memset(fl6, 0, sizeof(*fl6));
739 		fl6->flowi6_proto = IPPROTO_GRE;
740 		fl6->daddr = key->u.ipv6.dst;
741 		fl6->flowlabel = key->label;
742 		fl6->flowi6_uid = sock_net_uid(dev_net(dev), NULL);
743 
744 		dsfield = key->tos;
745 		flags = key->tun_flags &
746 			(TUNNEL_CSUM | TUNNEL_KEY | TUNNEL_SEQ);
747 		tunnel->tun_hlen = gre_calc_hlen(flags);
748 
749 		gre_build_header(skb, tunnel->tun_hlen,
750 				 flags, protocol,
751 				 tunnel_id_to_key32(tun_info->key.tun_id),
752 				 (flags & TUNNEL_SEQ) ? htonl(tunnel->o_seqno++)
753 						      : 0);
754 
755 	} else {
756 		if (tunnel->parms.o_flags & TUNNEL_SEQ)
757 			tunnel->o_seqno++;
758 
759 		gre_build_header(skb, tunnel->tun_hlen, tunnel->parms.o_flags,
760 				 protocol, tunnel->parms.o_key,
761 				 htonl(tunnel->o_seqno));
762 	}
763 
764 	return ip6_tnl_xmit(skb, dev, dsfield, fl6, encap_limit, pmtu,
765 			    NEXTHDR_GRE);
766 }
767 
768 static inline int ip6gre_xmit_ipv4(struct sk_buff *skb, struct net_device *dev)
769 {
770 	struct ip6_tnl *t = netdev_priv(dev);
771 	int encap_limit = -1;
772 	struct flowi6 fl6;
773 	__u8 dsfield = 0;
774 	__u32 mtu;
775 	int err;
776 
777 	memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
778 
779 	if (!t->parms.collect_md)
780 		prepare_ip6gre_xmit_ipv4(skb, dev, &fl6,
781 					 &dsfield, &encap_limit);
782 
783 	err = gre_handle_offloads(skb, !!(t->parms.o_flags & TUNNEL_CSUM));
784 	if (err)
785 		return -1;
786 
787 	err = __gre6_xmit(skb, dev, dsfield, &fl6, encap_limit, &mtu,
788 			  skb->protocol);
789 	if (err != 0) {
790 		/* XXX: send ICMP error even if DF is not set. */
791 		if (err == -EMSGSIZE)
792 			icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
793 				  htonl(mtu));
794 		return -1;
795 	}
796 
797 	return 0;
798 }
799 
800 static inline int ip6gre_xmit_ipv6(struct sk_buff *skb, struct net_device *dev)
801 {
802 	struct ip6_tnl *t = netdev_priv(dev);
803 	struct ipv6hdr *ipv6h = ipv6_hdr(skb);
804 	int encap_limit = -1;
805 	struct flowi6 fl6;
806 	__u8 dsfield = 0;
807 	__u32 mtu;
808 	int err;
809 
810 	if (ipv6_addr_equal(&t->parms.raddr, &ipv6h->saddr))
811 		return -1;
812 
813 	if (!t->parms.collect_md &&
814 	    prepare_ip6gre_xmit_ipv6(skb, dev, &fl6, &dsfield, &encap_limit))
815 		return -1;
816 
817 	if (gre_handle_offloads(skb, !!(t->parms.o_flags & TUNNEL_CSUM)))
818 		return -1;
819 
820 	err = __gre6_xmit(skb, dev, dsfield, &fl6, encap_limit,
821 			  &mtu, skb->protocol);
822 	if (err != 0) {
823 		if (err == -EMSGSIZE)
824 			icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
825 		return -1;
826 	}
827 
828 	return 0;
829 }
830 
831 /**
832  * ip6gre_tnl_addr_conflict - compare packet addresses to tunnel's own
833  *   @t: the outgoing tunnel device
834  *   @hdr: IPv6 header from the incoming packet
835  *
836  * Description:
837  *   Avoid trivial tunneling loop by checking that tunnel exit-point
838  *   doesn't match source of incoming packet.
839  *
840  * Return:
841  *   1 if conflict,
842  *   0 else
843  **/
844 
845 static inline bool ip6gre_tnl_addr_conflict(const struct ip6_tnl *t,
846 	const struct ipv6hdr *hdr)
847 {
848 	return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr);
849 }
850 
851 static int ip6gre_xmit_other(struct sk_buff *skb, struct net_device *dev)
852 {
853 	struct ip6_tnl *t = netdev_priv(dev);
854 	int encap_limit = -1;
855 	struct flowi6 fl6;
856 	__u32 mtu;
857 	int err;
858 
859 	if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
860 		encap_limit = t->parms.encap_limit;
861 
862 	if (!t->parms.collect_md)
863 		memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6));
864 
865 	err = gre_handle_offloads(skb, !!(t->parms.o_flags & TUNNEL_CSUM));
866 	if (err)
867 		return err;
868 
869 	err = __gre6_xmit(skb, dev, 0, &fl6, encap_limit, &mtu, skb->protocol);
870 
871 	return err;
872 }
873 
874 static netdev_tx_t ip6gre_tunnel_xmit(struct sk_buff *skb,
875 	struct net_device *dev)
876 {
877 	struct ip6_tnl *t = netdev_priv(dev);
878 	struct net_device_stats *stats = &t->dev->stats;
879 	int ret;
880 
881 	if (!pskb_inet_may_pull(skb))
882 		goto tx_err;
883 
884 	if (!ip6_tnl_xmit_ctl(t, &t->parms.laddr, &t->parms.raddr))
885 		goto tx_err;
886 
887 	switch (skb->protocol) {
888 	case htons(ETH_P_IP):
889 		ret = ip6gre_xmit_ipv4(skb, dev);
890 		break;
891 	case htons(ETH_P_IPV6):
892 		ret = ip6gre_xmit_ipv6(skb, dev);
893 		break;
894 	default:
895 		ret = ip6gre_xmit_other(skb, dev);
896 		break;
897 	}
898 
899 	if (ret < 0)
900 		goto tx_err;
901 
902 	return NETDEV_TX_OK;
903 
904 tx_err:
905 	stats->tx_errors++;
906 	stats->tx_dropped++;
907 	kfree_skb(skb);
908 	return NETDEV_TX_OK;
909 }
910 
911 static netdev_tx_t ip6erspan_tunnel_xmit(struct sk_buff *skb,
912 					 struct net_device *dev)
913 {
914 	struct ip6_tnl *t = netdev_priv(dev);
915 	struct dst_entry *dst = skb_dst(skb);
916 	struct net_device_stats *stats;
917 	bool truncate = false;
918 	int encap_limit = -1;
919 	__u8 dsfield = false;
920 	struct flowi6 fl6;
921 	int err = -EINVAL;
922 	__be16 proto;
923 	__u32 mtu;
924 	int nhoff;
925 	int thoff;
926 
927 	if (!pskb_inet_may_pull(skb))
928 		goto tx_err;
929 
930 	if (!ip6_tnl_xmit_ctl(t, &t->parms.laddr, &t->parms.raddr))
931 		goto tx_err;
932 
933 	if (gre_handle_offloads(skb, false))
934 		goto tx_err;
935 
936 	if (skb->len > dev->mtu + dev->hard_header_len) {
937 		pskb_trim(skb, dev->mtu + dev->hard_header_len);
938 		truncate = true;
939 	}
940 
941 	nhoff = skb_network_header(skb) - skb_mac_header(skb);
942 	if (skb->protocol == htons(ETH_P_IP) &&
943 	    (ntohs(ip_hdr(skb)->tot_len) > skb->len - nhoff))
944 		truncate = true;
945 
946 	thoff = skb_transport_header(skb) - skb_mac_header(skb);
947 	if (skb->protocol == htons(ETH_P_IPV6) &&
948 	    (ntohs(ipv6_hdr(skb)->payload_len) > skb->len - thoff))
949 		truncate = true;
950 
951 	if (skb_cow_head(skb, dev->needed_headroom ?: t->hlen))
952 		goto tx_err;
953 
954 	t->parms.o_flags &= ~TUNNEL_KEY;
955 	IPCB(skb)->flags = 0;
956 
957 	/* For collect_md mode, derive fl6 from the tunnel key,
958 	 * for native mode, call prepare_ip6gre_xmit_{ipv4,ipv6}.
959 	 */
960 	if (t->parms.collect_md) {
961 		struct ip_tunnel_info *tun_info;
962 		const struct ip_tunnel_key *key;
963 		struct erspan_metadata *md;
964 		__be32 tun_id;
965 
966 		tun_info = skb_tunnel_info(skb);
967 		if (unlikely(!tun_info ||
968 			     !(tun_info->mode & IP_TUNNEL_INFO_TX) ||
969 			     ip_tunnel_info_af(tun_info) != AF_INET6))
970 			return -EINVAL;
971 
972 		key = &tun_info->key;
973 		memset(&fl6, 0, sizeof(fl6));
974 		fl6.flowi6_proto = IPPROTO_GRE;
975 		fl6.daddr = key->u.ipv6.dst;
976 		fl6.flowlabel = key->label;
977 		fl6.flowi6_uid = sock_net_uid(dev_net(dev), NULL);
978 
979 		dsfield = key->tos;
980 		if (!(tun_info->key.tun_flags & TUNNEL_ERSPAN_OPT))
981 			goto tx_err;
982 		md = ip_tunnel_info_opts(tun_info);
983 		if (!md)
984 			goto tx_err;
985 
986 		tun_id = tunnel_id_to_key32(key->tun_id);
987 		if (md->version == 1) {
988 			erspan_build_header(skb,
989 					    ntohl(tun_id),
990 					    ntohl(md->u.index), truncate,
991 					    false);
992 		} else if (md->version == 2) {
993 			erspan_build_header_v2(skb,
994 					       ntohl(tun_id),
995 					       md->u.md2.dir,
996 					       get_hwid(&md->u.md2),
997 					       truncate, false);
998 		} else {
999 			goto tx_err;
1000 		}
1001 	} else {
1002 		switch (skb->protocol) {
1003 		case htons(ETH_P_IP):
1004 			memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
1005 			prepare_ip6gre_xmit_ipv4(skb, dev, &fl6,
1006 						 &dsfield, &encap_limit);
1007 			break;
1008 		case htons(ETH_P_IPV6):
1009 			if (ipv6_addr_equal(&t->parms.raddr, &ipv6_hdr(skb)->saddr))
1010 				goto tx_err;
1011 			if (prepare_ip6gre_xmit_ipv6(skb, dev, &fl6,
1012 						     &dsfield, &encap_limit))
1013 				goto tx_err;
1014 			break;
1015 		default:
1016 			memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6));
1017 			break;
1018 		}
1019 
1020 		if (t->parms.erspan_ver == 1)
1021 			erspan_build_header(skb, ntohl(t->parms.o_key),
1022 					    t->parms.index,
1023 					    truncate, false);
1024 		else if (t->parms.erspan_ver == 2)
1025 			erspan_build_header_v2(skb, ntohl(t->parms.o_key),
1026 					       t->parms.dir,
1027 					       t->parms.hwid,
1028 					       truncate, false);
1029 		else
1030 			goto tx_err;
1031 
1032 		fl6.daddr = t->parms.raddr;
1033 	}
1034 
1035 	/* Push GRE header. */
1036 	proto = (t->parms.erspan_ver == 1) ? htons(ETH_P_ERSPAN)
1037 					   : htons(ETH_P_ERSPAN2);
1038 	gre_build_header(skb, 8, TUNNEL_SEQ, proto, 0, htonl(t->o_seqno++));
1039 
1040 	/* TooBig packet may have updated dst->dev's mtu */
1041 	if (!t->parms.collect_md && dst && dst_mtu(dst) > dst->dev->mtu)
1042 		dst->ops->update_pmtu(dst, NULL, skb, dst->dev->mtu);
1043 
1044 	err = ip6_tnl_xmit(skb, dev, dsfield, &fl6, encap_limit, &mtu,
1045 			   NEXTHDR_GRE);
1046 	if (err != 0) {
1047 		/* XXX: send ICMP error even if DF is not set. */
1048 		if (err == -EMSGSIZE) {
1049 			if (skb->protocol == htons(ETH_P_IP))
1050 				icmp_send(skb, ICMP_DEST_UNREACH,
1051 					  ICMP_FRAG_NEEDED, htonl(mtu));
1052 			else
1053 				icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
1054 		}
1055 
1056 		goto tx_err;
1057 	}
1058 	return NETDEV_TX_OK;
1059 
1060 tx_err:
1061 	stats = &t->dev->stats;
1062 	stats->tx_errors++;
1063 	stats->tx_dropped++;
1064 	kfree_skb(skb);
1065 	return NETDEV_TX_OK;
1066 }
1067 
1068 static void ip6gre_tnl_link_config_common(struct ip6_tnl *t)
1069 {
1070 	struct net_device *dev = t->dev;
1071 	struct __ip6_tnl_parm *p = &t->parms;
1072 	struct flowi6 *fl6 = &t->fl.u.ip6;
1073 
1074 	if (dev->type != ARPHRD_ETHER) {
1075 		memcpy(dev->dev_addr, &p->laddr, sizeof(struct in6_addr));
1076 		memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr));
1077 	}
1078 
1079 	/* Set up flowi template */
1080 	fl6->saddr = p->laddr;
1081 	fl6->daddr = p->raddr;
1082 	fl6->flowi6_oif = p->link;
1083 	fl6->flowlabel = 0;
1084 	fl6->flowi6_proto = IPPROTO_GRE;
1085 
1086 	if (!(p->flags&IP6_TNL_F_USE_ORIG_TCLASS))
1087 		fl6->flowlabel |= IPV6_TCLASS_MASK & p->flowinfo;
1088 	if (!(p->flags&IP6_TNL_F_USE_ORIG_FLOWLABEL))
1089 		fl6->flowlabel |= IPV6_FLOWLABEL_MASK & p->flowinfo;
1090 
1091 	p->flags &= ~(IP6_TNL_F_CAP_XMIT|IP6_TNL_F_CAP_RCV|IP6_TNL_F_CAP_PER_PACKET);
1092 	p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr);
1093 
1094 	if (p->flags&IP6_TNL_F_CAP_XMIT &&
1095 			p->flags&IP6_TNL_F_CAP_RCV && dev->type != ARPHRD_ETHER)
1096 		dev->flags |= IFF_POINTOPOINT;
1097 	else
1098 		dev->flags &= ~IFF_POINTOPOINT;
1099 }
1100 
1101 static void ip6gre_tnl_link_config_route(struct ip6_tnl *t, int set_mtu,
1102 					 int t_hlen)
1103 {
1104 	const struct __ip6_tnl_parm *p = &t->parms;
1105 	struct net_device *dev = t->dev;
1106 
1107 	if (p->flags & IP6_TNL_F_CAP_XMIT) {
1108 		int strict = (ipv6_addr_type(&p->raddr) &
1109 			      (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL));
1110 
1111 		struct rt6_info *rt = rt6_lookup(t->net,
1112 						 &p->raddr, &p->laddr,
1113 						 p->link, NULL, strict);
1114 
1115 		if (!rt)
1116 			return;
1117 
1118 		if (rt->dst.dev) {
1119 			dev->needed_headroom = rt->dst.dev->hard_header_len +
1120 					       t_hlen;
1121 
1122 			if (set_mtu) {
1123 				dev->mtu = rt->dst.dev->mtu - t_hlen;
1124 				if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1125 					dev->mtu -= 8;
1126 				if (dev->type == ARPHRD_ETHER)
1127 					dev->mtu -= ETH_HLEN;
1128 
1129 				if (dev->mtu < IPV6_MIN_MTU)
1130 					dev->mtu = IPV6_MIN_MTU;
1131 			}
1132 		}
1133 		ip6_rt_put(rt);
1134 	}
1135 }
1136 
1137 static int ip6gre_calc_hlen(struct ip6_tnl *tunnel)
1138 {
1139 	int t_hlen;
1140 
1141 	tunnel->tun_hlen = gre_calc_hlen(tunnel->parms.o_flags);
1142 	tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen;
1143 
1144 	t_hlen = tunnel->hlen + sizeof(struct ipv6hdr);
1145 	tunnel->dev->needed_headroom = LL_MAX_HEADER + t_hlen;
1146 	return t_hlen;
1147 }
1148 
1149 static void ip6gre_tnl_link_config(struct ip6_tnl *t, int set_mtu)
1150 {
1151 	ip6gre_tnl_link_config_common(t);
1152 	ip6gre_tnl_link_config_route(t, set_mtu, ip6gre_calc_hlen(t));
1153 }
1154 
1155 static void ip6gre_tnl_copy_tnl_parm(struct ip6_tnl *t,
1156 				     const struct __ip6_tnl_parm *p)
1157 {
1158 	t->parms.laddr = p->laddr;
1159 	t->parms.raddr = p->raddr;
1160 	t->parms.flags = p->flags;
1161 	t->parms.hop_limit = p->hop_limit;
1162 	t->parms.encap_limit = p->encap_limit;
1163 	t->parms.flowinfo = p->flowinfo;
1164 	t->parms.link = p->link;
1165 	t->parms.proto = p->proto;
1166 	t->parms.i_key = p->i_key;
1167 	t->parms.o_key = p->o_key;
1168 	t->parms.i_flags = p->i_flags;
1169 	t->parms.o_flags = p->o_flags;
1170 	t->parms.fwmark = p->fwmark;
1171 	t->parms.erspan_ver = p->erspan_ver;
1172 	t->parms.index = p->index;
1173 	t->parms.dir = p->dir;
1174 	t->parms.hwid = p->hwid;
1175 	dst_cache_reset(&t->dst_cache);
1176 }
1177 
1178 static int ip6gre_tnl_change(struct ip6_tnl *t, const struct __ip6_tnl_parm *p,
1179 			     int set_mtu)
1180 {
1181 	ip6gre_tnl_copy_tnl_parm(t, p);
1182 	ip6gre_tnl_link_config(t, set_mtu);
1183 	return 0;
1184 }
1185 
1186 static void ip6gre_tnl_parm_from_user(struct __ip6_tnl_parm *p,
1187 	const struct ip6_tnl_parm2 *u)
1188 {
1189 	p->laddr = u->laddr;
1190 	p->raddr = u->raddr;
1191 	p->flags = u->flags;
1192 	p->hop_limit = u->hop_limit;
1193 	p->encap_limit = u->encap_limit;
1194 	p->flowinfo = u->flowinfo;
1195 	p->link = u->link;
1196 	p->i_key = u->i_key;
1197 	p->o_key = u->o_key;
1198 	p->i_flags = gre_flags_to_tnl_flags(u->i_flags);
1199 	p->o_flags = gre_flags_to_tnl_flags(u->o_flags);
1200 	memcpy(p->name, u->name, sizeof(u->name));
1201 }
1202 
1203 static void ip6gre_tnl_parm_to_user(struct ip6_tnl_parm2 *u,
1204 	const struct __ip6_tnl_parm *p)
1205 {
1206 	u->proto = IPPROTO_GRE;
1207 	u->laddr = p->laddr;
1208 	u->raddr = p->raddr;
1209 	u->flags = p->flags;
1210 	u->hop_limit = p->hop_limit;
1211 	u->encap_limit = p->encap_limit;
1212 	u->flowinfo = p->flowinfo;
1213 	u->link = p->link;
1214 	u->i_key = p->i_key;
1215 	u->o_key = p->o_key;
1216 	u->i_flags = gre_tnl_flags_to_gre_flags(p->i_flags);
1217 	u->o_flags = gre_tnl_flags_to_gre_flags(p->o_flags);
1218 	memcpy(u->name, p->name, sizeof(u->name));
1219 }
1220 
1221 static int ip6gre_tunnel_ioctl(struct net_device *dev,
1222 	struct ifreq *ifr, int cmd)
1223 {
1224 	int err = 0;
1225 	struct ip6_tnl_parm2 p;
1226 	struct __ip6_tnl_parm p1;
1227 	struct ip6_tnl *t = netdev_priv(dev);
1228 	struct net *net = t->net;
1229 	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
1230 
1231 	memset(&p1, 0, sizeof(p1));
1232 
1233 	switch (cmd) {
1234 	case SIOCGETTUNNEL:
1235 		if (dev == ign->fb_tunnel_dev) {
1236 			if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) {
1237 				err = -EFAULT;
1238 				break;
1239 			}
1240 			ip6gre_tnl_parm_from_user(&p1, &p);
1241 			t = ip6gre_tunnel_locate(net, &p1, 0);
1242 			if (!t)
1243 				t = netdev_priv(dev);
1244 		}
1245 		memset(&p, 0, sizeof(p));
1246 		ip6gre_tnl_parm_to_user(&p, &t->parms);
1247 		if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
1248 			err = -EFAULT;
1249 		break;
1250 
1251 	case SIOCADDTUNNEL:
1252 	case SIOCCHGTUNNEL:
1253 		err = -EPERM;
1254 		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1255 			goto done;
1256 
1257 		err = -EFAULT;
1258 		if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
1259 			goto done;
1260 
1261 		err = -EINVAL;
1262 		if ((p.i_flags|p.o_flags)&(GRE_VERSION|GRE_ROUTING))
1263 			goto done;
1264 
1265 		if (!(p.i_flags&GRE_KEY))
1266 			p.i_key = 0;
1267 		if (!(p.o_flags&GRE_KEY))
1268 			p.o_key = 0;
1269 
1270 		ip6gre_tnl_parm_from_user(&p1, &p);
1271 		t = ip6gre_tunnel_locate(net, &p1, cmd == SIOCADDTUNNEL);
1272 
1273 		if (dev != ign->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) {
1274 			if (t) {
1275 				if (t->dev != dev) {
1276 					err = -EEXIST;
1277 					break;
1278 				}
1279 			} else {
1280 				t = netdev_priv(dev);
1281 
1282 				ip6gre_tunnel_unlink(ign, t);
1283 				synchronize_net();
1284 				ip6gre_tnl_change(t, &p1, 1);
1285 				ip6gre_tunnel_link(ign, t);
1286 				netdev_state_change(dev);
1287 			}
1288 		}
1289 
1290 		if (t) {
1291 			err = 0;
1292 
1293 			memset(&p, 0, sizeof(p));
1294 			ip6gre_tnl_parm_to_user(&p, &t->parms);
1295 			if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
1296 				err = -EFAULT;
1297 		} else
1298 			err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
1299 		break;
1300 
1301 	case SIOCDELTUNNEL:
1302 		err = -EPERM;
1303 		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1304 			goto done;
1305 
1306 		if (dev == ign->fb_tunnel_dev) {
1307 			err = -EFAULT;
1308 			if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
1309 				goto done;
1310 			err = -ENOENT;
1311 			ip6gre_tnl_parm_from_user(&p1, &p);
1312 			t = ip6gre_tunnel_locate(net, &p1, 0);
1313 			if (!t)
1314 				goto done;
1315 			err = -EPERM;
1316 			if (t == netdev_priv(ign->fb_tunnel_dev))
1317 				goto done;
1318 			dev = t->dev;
1319 		}
1320 		unregister_netdevice(dev);
1321 		err = 0;
1322 		break;
1323 
1324 	default:
1325 		err = -EINVAL;
1326 	}
1327 
1328 done:
1329 	return err;
1330 }
1331 
1332 static int ip6gre_header(struct sk_buff *skb, struct net_device *dev,
1333 			 unsigned short type, const void *daddr,
1334 			 const void *saddr, unsigned int len)
1335 {
1336 	struct ip6_tnl *t = netdev_priv(dev);
1337 	struct ipv6hdr *ipv6h;
1338 	__be16 *p;
1339 
1340 	ipv6h = skb_push(skb, t->hlen + sizeof(*ipv6h));
1341 	ip6_flow_hdr(ipv6h, 0, ip6_make_flowlabel(dev_net(dev), skb,
1342 						  t->fl.u.ip6.flowlabel,
1343 						  true, &t->fl.u.ip6));
1344 	ipv6h->hop_limit = t->parms.hop_limit;
1345 	ipv6h->nexthdr = NEXTHDR_GRE;
1346 	ipv6h->saddr = t->parms.laddr;
1347 	ipv6h->daddr = t->parms.raddr;
1348 
1349 	p = (__be16 *)(ipv6h + 1);
1350 	p[0] = t->parms.o_flags;
1351 	p[1] = htons(type);
1352 
1353 	/*
1354 	 *	Set the source hardware address.
1355 	 */
1356 
1357 	if (saddr)
1358 		memcpy(&ipv6h->saddr, saddr, sizeof(struct in6_addr));
1359 	if (daddr)
1360 		memcpy(&ipv6h->daddr, daddr, sizeof(struct in6_addr));
1361 	if (!ipv6_addr_any(&ipv6h->daddr))
1362 		return t->hlen;
1363 
1364 	return -t->hlen;
1365 }
1366 
1367 static const struct header_ops ip6gre_header_ops = {
1368 	.create	= ip6gre_header,
1369 };
1370 
1371 static const struct net_device_ops ip6gre_netdev_ops = {
1372 	.ndo_init		= ip6gre_tunnel_init,
1373 	.ndo_uninit		= ip6gre_tunnel_uninit,
1374 	.ndo_start_xmit		= ip6gre_tunnel_xmit,
1375 	.ndo_do_ioctl		= ip6gre_tunnel_ioctl,
1376 	.ndo_change_mtu		= ip6_tnl_change_mtu,
1377 	.ndo_get_stats64	= ip_tunnel_get_stats64,
1378 	.ndo_get_iflink		= ip6_tnl_get_iflink,
1379 };
1380 
1381 static void ip6gre_dev_free(struct net_device *dev)
1382 {
1383 	struct ip6_tnl *t = netdev_priv(dev);
1384 
1385 	gro_cells_destroy(&t->gro_cells);
1386 	dst_cache_destroy(&t->dst_cache);
1387 	free_percpu(dev->tstats);
1388 }
1389 
1390 static void ip6gre_tunnel_setup(struct net_device *dev)
1391 {
1392 	dev->netdev_ops = &ip6gre_netdev_ops;
1393 	dev->needs_free_netdev = true;
1394 	dev->priv_destructor = ip6gre_dev_free;
1395 
1396 	dev->type = ARPHRD_IP6GRE;
1397 
1398 	dev->flags |= IFF_NOARP;
1399 	dev->addr_len = sizeof(struct in6_addr);
1400 	netif_keep_dst(dev);
1401 	/* This perm addr will be used as interface identifier by IPv6 */
1402 	dev->addr_assign_type = NET_ADDR_RANDOM;
1403 	eth_random_addr(dev->perm_addr);
1404 }
1405 
1406 #define GRE6_FEATURES (NETIF_F_SG |		\
1407 		       NETIF_F_FRAGLIST |	\
1408 		       NETIF_F_HIGHDMA |	\
1409 		       NETIF_F_HW_CSUM)
1410 
1411 static void ip6gre_tnl_init_features(struct net_device *dev)
1412 {
1413 	struct ip6_tnl *nt = netdev_priv(dev);
1414 
1415 	dev->features		|= GRE6_FEATURES;
1416 	dev->hw_features	|= GRE6_FEATURES;
1417 
1418 	if (!(nt->parms.o_flags & TUNNEL_SEQ)) {
1419 		/* TCP offload with GRE SEQ is not supported, nor
1420 		 * can we support 2 levels of outer headers requiring
1421 		 * an update.
1422 		 */
1423 		if (!(nt->parms.o_flags & TUNNEL_CSUM) ||
1424 		    nt->encap.type == TUNNEL_ENCAP_NONE) {
1425 			dev->features    |= NETIF_F_GSO_SOFTWARE;
1426 			dev->hw_features |= NETIF_F_GSO_SOFTWARE;
1427 		}
1428 
1429 		/* Can use a lockless transmit, unless we generate
1430 		 * output sequences
1431 		 */
1432 		dev->features |= NETIF_F_LLTX;
1433 	}
1434 }
1435 
1436 static int ip6gre_tunnel_init_common(struct net_device *dev)
1437 {
1438 	struct ip6_tnl *tunnel;
1439 	int ret;
1440 	int t_hlen;
1441 
1442 	tunnel = netdev_priv(dev);
1443 
1444 	tunnel->dev = dev;
1445 	tunnel->net = dev_net(dev);
1446 	strcpy(tunnel->parms.name, dev->name);
1447 
1448 	dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
1449 	if (!dev->tstats)
1450 		return -ENOMEM;
1451 
1452 	ret = dst_cache_init(&tunnel->dst_cache, GFP_KERNEL);
1453 	if (ret)
1454 		goto cleanup_alloc_pcpu_stats;
1455 
1456 	ret = gro_cells_init(&tunnel->gro_cells, dev);
1457 	if (ret)
1458 		goto cleanup_dst_cache_init;
1459 
1460 	t_hlen = ip6gre_calc_hlen(tunnel);
1461 	dev->mtu = ETH_DATA_LEN - t_hlen;
1462 	if (dev->type == ARPHRD_ETHER)
1463 		dev->mtu -= ETH_HLEN;
1464 	if (!(tunnel->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1465 		dev->mtu -= 8;
1466 
1467 	if (tunnel->parms.collect_md) {
1468 		dev->features |= NETIF_F_NETNS_LOCAL;
1469 		netif_keep_dst(dev);
1470 	}
1471 	ip6gre_tnl_init_features(dev);
1472 
1473 	return 0;
1474 
1475 cleanup_dst_cache_init:
1476 	dst_cache_destroy(&tunnel->dst_cache);
1477 cleanup_alloc_pcpu_stats:
1478 	free_percpu(dev->tstats);
1479 	dev->tstats = NULL;
1480 	return ret;
1481 }
1482 
1483 static int ip6gre_tunnel_init(struct net_device *dev)
1484 {
1485 	struct ip6_tnl *tunnel;
1486 	int ret;
1487 
1488 	ret = ip6gre_tunnel_init_common(dev);
1489 	if (ret)
1490 		return ret;
1491 
1492 	tunnel = netdev_priv(dev);
1493 
1494 	if (tunnel->parms.collect_md)
1495 		return 0;
1496 
1497 	memcpy(dev->dev_addr, &tunnel->parms.laddr, sizeof(struct in6_addr));
1498 	memcpy(dev->broadcast, &tunnel->parms.raddr, sizeof(struct in6_addr));
1499 
1500 	if (ipv6_addr_any(&tunnel->parms.raddr))
1501 		dev->header_ops = &ip6gre_header_ops;
1502 
1503 	return 0;
1504 }
1505 
1506 static void ip6gre_fb_tunnel_init(struct net_device *dev)
1507 {
1508 	struct ip6_tnl *tunnel = netdev_priv(dev);
1509 
1510 	tunnel->dev = dev;
1511 	tunnel->net = dev_net(dev);
1512 	strcpy(tunnel->parms.name, dev->name);
1513 
1514 	tunnel->hlen		= sizeof(struct ipv6hdr) + 4;
1515 
1516 	dev_hold(dev);
1517 }
1518 
1519 static struct inet6_protocol ip6gre_protocol __read_mostly = {
1520 	.handler     = gre_rcv,
1521 	.err_handler = ip6gre_err,
1522 	.flags       = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
1523 };
1524 
1525 static void ip6gre_destroy_tunnels(struct net *net, struct list_head *head)
1526 {
1527 	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
1528 	struct net_device *dev, *aux;
1529 	int prio;
1530 
1531 	for_each_netdev_safe(net, dev, aux)
1532 		if (dev->rtnl_link_ops == &ip6gre_link_ops ||
1533 		    dev->rtnl_link_ops == &ip6gre_tap_ops ||
1534 		    dev->rtnl_link_ops == &ip6erspan_tap_ops)
1535 			unregister_netdevice_queue(dev, head);
1536 
1537 	for (prio = 0; prio < 4; prio++) {
1538 		int h;
1539 		for (h = 0; h < IP6_GRE_HASH_SIZE; h++) {
1540 			struct ip6_tnl *t;
1541 
1542 			t = rtnl_dereference(ign->tunnels[prio][h]);
1543 
1544 			while (t) {
1545 				/* If dev is in the same netns, it has already
1546 				 * been added to the list by the previous loop.
1547 				 */
1548 				if (!net_eq(dev_net(t->dev), net))
1549 					unregister_netdevice_queue(t->dev,
1550 								   head);
1551 				t = rtnl_dereference(t->next);
1552 			}
1553 		}
1554 	}
1555 }
1556 
1557 static int __net_init ip6gre_init_net(struct net *net)
1558 {
1559 	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
1560 	int err;
1561 
1562 	if (!net_has_fallback_tunnels(net))
1563 		return 0;
1564 	ign->fb_tunnel_dev = alloc_netdev(sizeof(struct ip6_tnl), "ip6gre0",
1565 					  NET_NAME_UNKNOWN,
1566 					  ip6gre_tunnel_setup);
1567 	if (!ign->fb_tunnel_dev) {
1568 		err = -ENOMEM;
1569 		goto err_alloc_dev;
1570 	}
1571 	dev_net_set(ign->fb_tunnel_dev, net);
1572 	/* FB netdevice is special: we have one, and only one per netns.
1573 	 * Allowing to move it to another netns is clearly unsafe.
1574 	 */
1575 	ign->fb_tunnel_dev->features |= NETIF_F_NETNS_LOCAL;
1576 
1577 
1578 	ip6gre_fb_tunnel_init(ign->fb_tunnel_dev);
1579 	ign->fb_tunnel_dev->rtnl_link_ops = &ip6gre_link_ops;
1580 
1581 	err = register_netdev(ign->fb_tunnel_dev);
1582 	if (err)
1583 		goto err_reg_dev;
1584 
1585 	rcu_assign_pointer(ign->tunnels_wc[0],
1586 			   netdev_priv(ign->fb_tunnel_dev));
1587 	return 0;
1588 
1589 err_reg_dev:
1590 	free_netdev(ign->fb_tunnel_dev);
1591 err_alloc_dev:
1592 	return err;
1593 }
1594 
1595 static void __net_exit ip6gre_exit_batch_net(struct list_head *net_list)
1596 {
1597 	struct net *net;
1598 	LIST_HEAD(list);
1599 
1600 	rtnl_lock();
1601 	list_for_each_entry(net, net_list, exit_list)
1602 		ip6gre_destroy_tunnels(net, &list);
1603 	unregister_netdevice_many(&list);
1604 	rtnl_unlock();
1605 }
1606 
1607 static struct pernet_operations ip6gre_net_ops = {
1608 	.init = ip6gre_init_net,
1609 	.exit_batch = ip6gre_exit_batch_net,
1610 	.id   = &ip6gre_net_id,
1611 	.size = sizeof(struct ip6gre_net),
1612 };
1613 
1614 static int ip6gre_tunnel_validate(struct nlattr *tb[], struct nlattr *data[],
1615 				  struct netlink_ext_ack *extack)
1616 {
1617 	__be16 flags;
1618 
1619 	if (!data)
1620 		return 0;
1621 
1622 	flags = 0;
1623 	if (data[IFLA_GRE_IFLAGS])
1624 		flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]);
1625 	if (data[IFLA_GRE_OFLAGS])
1626 		flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]);
1627 	if (flags & (GRE_VERSION|GRE_ROUTING))
1628 		return -EINVAL;
1629 
1630 	return 0;
1631 }
1632 
1633 static int ip6gre_tap_validate(struct nlattr *tb[], struct nlattr *data[],
1634 			       struct netlink_ext_ack *extack)
1635 {
1636 	struct in6_addr daddr;
1637 
1638 	if (tb[IFLA_ADDRESS]) {
1639 		if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
1640 			return -EINVAL;
1641 		if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
1642 			return -EADDRNOTAVAIL;
1643 	}
1644 
1645 	if (!data)
1646 		goto out;
1647 
1648 	if (data[IFLA_GRE_REMOTE]) {
1649 		daddr = nla_get_in6_addr(data[IFLA_GRE_REMOTE]);
1650 		if (ipv6_addr_any(&daddr))
1651 			return -EINVAL;
1652 	}
1653 
1654 out:
1655 	return ip6gre_tunnel_validate(tb, data, extack);
1656 }
1657 
1658 static int ip6erspan_tap_validate(struct nlattr *tb[], struct nlattr *data[],
1659 				  struct netlink_ext_ack *extack)
1660 {
1661 	__be16 flags = 0;
1662 	int ret, ver = 0;
1663 
1664 	if (!data)
1665 		return 0;
1666 
1667 	ret = ip6gre_tap_validate(tb, data, extack);
1668 	if (ret)
1669 		return ret;
1670 
1671 	/* ERSPAN should only have GRE sequence and key flag */
1672 	if (data[IFLA_GRE_OFLAGS])
1673 		flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]);
1674 	if (data[IFLA_GRE_IFLAGS])
1675 		flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]);
1676 	if (!data[IFLA_GRE_COLLECT_METADATA] &&
1677 	    flags != (GRE_SEQ | GRE_KEY))
1678 		return -EINVAL;
1679 
1680 	/* ERSPAN Session ID only has 10-bit. Since we reuse
1681 	 * 32-bit key field as ID, check it's range.
1682 	 */
1683 	if (data[IFLA_GRE_IKEY] &&
1684 	    (ntohl(nla_get_be32(data[IFLA_GRE_IKEY])) & ~ID_MASK))
1685 		return -EINVAL;
1686 
1687 	if (data[IFLA_GRE_OKEY] &&
1688 	    (ntohl(nla_get_be32(data[IFLA_GRE_OKEY])) & ~ID_MASK))
1689 		return -EINVAL;
1690 
1691 	if (data[IFLA_GRE_ERSPAN_VER]) {
1692 		ver = nla_get_u8(data[IFLA_GRE_ERSPAN_VER]);
1693 		if (ver != 1 && ver != 2)
1694 			return -EINVAL;
1695 	}
1696 
1697 	if (ver == 1) {
1698 		if (data[IFLA_GRE_ERSPAN_INDEX]) {
1699 			u32 index = nla_get_u32(data[IFLA_GRE_ERSPAN_INDEX]);
1700 
1701 			if (index & ~INDEX_MASK)
1702 				return -EINVAL;
1703 		}
1704 	} else if (ver == 2) {
1705 		if (data[IFLA_GRE_ERSPAN_DIR]) {
1706 			u16 dir = nla_get_u8(data[IFLA_GRE_ERSPAN_DIR]);
1707 
1708 			if (dir & ~(DIR_MASK >> DIR_OFFSET))
1709 				return -EINVAL;
1710 		}
1711 
1712 		if (data[IFLA_GRE_ERSPAN_HWID]) {
1713 			u16 hwid = nla_get_u16(data[IFLA_GRE_ERSPAN_HWID]);
1714 
1715 			if (hwid & ~(HWID_MASK >> HWID_OFFSET))
1716 				return -EINVAL;
1717 		}
1718 	}
1719 
1720 	return 0;
1721 }
1722 
1723 static void ip6erspan_set_version(struct nlattr *data[],
1724 				  struct __ip6_tnl_parm *parms)
1725 {
1726 	if (!data)
1727 		return;
1728 
1729 	parms->erspan_ver = 1;
1730 	if (data[IFLA_GRE_ERSPAN_VER])
1731 		parms->erspan_ver = nla_get_u8(data[IFLA_GRE_ERSPAN_VER]);
1732 
1733 	if (parms->erspan_ver == 1) {
1734 		if (data[IFLA_GRE_ERSPAN_INDEX])
1735 			parms->index = nla_get_u32(data[IFLA_GRE_ERSPAN_INDEX]);
1736 	} else if (parms->erspan_ver == 2) {
1737 		if (data[IFLA_GRE_ERSPAN_DIR])
1738 			parms->dir = nla_get_u8(data[IFLA_GRE_ERSPAN_DIR]);
1739 		if (data[IFLA_GRE_ERSPAN_HWID])
1740 			parms->hwid = nla_get_u16(data[IFLA_GRE_ERSPAN_HWID]);
1741 	}
1742 }
1743 
1744 static void ip6gre_netlink_parms(struct nlattr *data[],
1745 				struct __ip6_tnl_parm *parms)
1746 {
1747 	memset(parms, 0, sizeof(*parms));
1748 
1749 	if (!data)
1750 		return;
1751 
1752 	if (data[IFLA_GRE_LINK])
1753 		parms->link = nla_get_u32(data[IFLA_GRE_LINK]);
1754 
1755 	if (data[IFLA_GRE_IFLAGS])
1756 		parms->i_flags = gre_flags_to_tnl_flags(
1757 				nla_get_be16(data[IFLA_GRE_IFLAGS]));
1758 
1759 	if (data[IFLA_GRE_OFLAGS])
1760 		parms->o_flags = gre_flags_to_tnl_flags(
1761 				nla_get_be16(data[IFLA_GRE_OFLAGS]));
1762 
1763 	if (data[IFLA_GRE_IKEY])
1764 		parms->i_key = nla_get_be32(data[IFLA_GRE_IKEY]);
1765 
1766 	if (data[IFLA_GRE_OKEY])
1767 		parms->o_key = nla_get_be32(data[IFLA_GRE_OKEY]);
1768 
1769 	if (data[IFLA_GRE_LOCAL])
1770 		parms->laddr = nla_get_in6_addr(data[IFLA_GRE_LOCAL]);
1771 
1772 	if (data[IFLA_GRE_REMOTE])
1773 		parms->raddr = nla_get_in6_addr(data[IFLA_GRE_REMOTE]);
1774 
1775 	if (data[IFLA_GRE_TTL])
1776 		parms->hop_limit = nla_get_u8(data[IFLA_GRE_TTL]);
1777 
1778 	if (data[IFLA_GRE_ENCAP_LIMIT])
1779 		parms->encap_limit = nla_get_u8(data[IFLA_GRE_ENCAP_LIMIT]);
1780 
1781 	if (data[IFLA_GRE_FLOWINFO])
1782 		parms->flowinfo = nla_get_be32(data[IFLA_GRE_FLOWINFO]);
1783 
1784 	if (data[IFLA_GRE_FLAGS])
1785 		parms->flags = nla_get_u32(data[IFLA_GRE_FLAGS]);
1786 
1787 	if (data[IFLA_GRE_FWMARK])
1788 		parms->fwmark = nla_get_u32(data[IFLA_GRE_FWMARK]);
1789 
1790 	if (data[IFLA_GRE_COLLECT_METADATA])
1791 		parms->collect_md = true;
1792 }
1793 
1794 static int ip6gre_tap_init(struct net_device *dev)
1795 {
1796 	int ret;
1797 
1798 	ret = ip6gre_tunnel_init_common(dev);
1799 	if (ret)
1800 		return ret;
1801 
1802 	dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1803 
1804 	return 0;
1805 }
1806 
1807 static const struct net_device_ops ip6gre_tap_netdev_ops = {
1808 	.ndo_init = ip6gre_tap_init,
1809 	.ndo_uninit = ip6gre_tunnel_uninit,
1810 	.ndo_start_xmit = ip6gre_tunnel_xmit,
1811 	.ndo_set_mac_address = eth_mac_addr,
1812 	.ndo_validate_addr = eth_validate_addr,
1813 	.ndo_change_mtu = ip6_tnl_change_mtu,
1814 	.ndo_get_stats64 = ip_tunnel_get_stats64,
1815 	.ndo_get_iflink = ip6_tnl_get_iflink,
1816 };
1817 
1818 static int ip6erspan_calc_hlen(struct ip6_tnl *tunnel)
1819 {
1820 	int t_hlen;
1821 
1822 	tunnel->tun_hlen = 8;
1823 	tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen +
1824 		       erspan_hdr_len(tunnel->parms.erspan_ver);
1825 
1826 	t_hlen = tunnel->hlen + sizeof(struct ipv6hdr);
1827 	tunnel->dev->needed_headroom = LL_MAX_HEADER + t_hlen;
1828 	return t_hlen;
1829 }
1830 
1831 static int ip6erspan_tap_init(struct net_device *dev)
1832 {
1833 	struct ip6_tnl *tunnel;
1834 	int t_hlen;
1835 	int ret;
1836 
1837 	tunnel = netdev_priv(dev);
1838 
1839 	tunnel->dev = dev;
1840 	tunnel->net = dev_net(dev);
1841 	strcpy(tunnel->parms.name, dev->name);
1842 
1843 	dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
1844 	if (!dev->tstats)
1845 		return -ENOMEM;
1846 
1847 	ret = dst_cache_init(&tunnel->dst_cache, GFP_KERNEL);
1848 	if (ret)
1849 		goto cleanup_alloc_pcpu_stats;
1850 
1851 	ret = gro_cells_init(&tunnel->gro_cells, dev);
1852 	if (ret)
1853 		goto cleanup_dst_cache_init;
1854 
1855 	t_hlen = ip6erspan_calc_hlen(tunnel);
1856 	dev->mtu = ETH_DATA_LEN - t_hlen;
1857 	if (dev->type == ARPHRD_ETHER)
1858 		dev->mtu -= ETH_HLEN;
1859 	if (!(tunnel->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1860 		dev->mtu -= 8;
1861 
1862 	dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1863 	ip6erspan_tnl_link_config(tunnel, 1);
1864 
1865 	return 0;
1866 
1867 cleanup_dst_cache_init:
1868 	dst_cache_destroy(&tunnel->dst_cache);
1869 cleanup_alloc_pcpu_stats:
1870 	free_percpu(dev->tstats);
1871 	dev->tstats = NULL;
1872 	return ret;
1873 }
1874 
1875 static const struct net_device_ops ip6erspan_netdev_ops = {
1876 	.ndo_init =		ip6erspan_tap_init,
1877 	.ndo_uninit =		ip6erspan_tunnel_uninit,
1878 	.ndo_start_xmit =	ip6erspan_tunnel_xmit,
1879 	.ndo_set_mac_address =	eth_mac_addr,
1880 	.ndo_validate_addr =	eth_validate_addr,
1881 	.ndo_change_mtu =	ip6_tnl_change_mtu,
1882 	.ndo_get_stats64 =	ip_tunnel_get_stats64,
1883 	.ndo_get_iflink =	ip6_tnl_get_iflink,
1884 };
1885 
1886 static void ip6gre_tap_setup(struct net_device *dev)
1887 {
1888 
1889 	ether_setup(dev);
1890 
1891 	dev->max_mtu = 0;
1892 	dev->netdev_ops = &ip6gre_tap_netdev_ops;
1893 	dev->needs_free_netdev = true;
1894 	dev->priv_destructor = ip6gre_dev_free;
1895 
1896 	dev->features |= NETIF_F_NETNS_LOCAL;
1897 	dev->priv_flags &= ~IFF_TX_SKB_SHARING;
1898 	dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1899 	netif_keep_dst(dev);
1900 }
1901 
1902 static bool ip6gre_netlink_encap_parms(struct nlattr *data[],
1903 				       struct ip_tunnel_encap *ipencap)
1904 {
1905 	bool ret = false;
1906 
1907 	memset(ipencap, 0, sizeof(*ipencap));
1908 
1909 	if (!data)
1910 		return ret;
1911 
1912 	if (data[IFLA_GRE_ENCAP_TYPE]) {
1913 		ret = true;
1914 		ipencap->type = nla_get_u16(data[IFLA_GRE_ENCAP_TYPE]);
1915 	}
1916 
1917 	if (data[IFLA_GRE_ENCAP_FLAGS]) {
1918 		ret = true;
1919 		ipencap->flags = nla_get_u16(data[IFLA_GRE_ENCAP_FLAGS]);
1920 	}
1921 
1922 	if (data[IFLA_GRE_ENCAP_SPORT]) {
1923 		ret = true;
1924 		ipencap->sport = nla_get_be16(data[IFLA_GRE_ENCAP_SPORT]);
1925 	}
1926 
1927 	if (data[IFLA_GRE_ENCAP_DPORT]) {
1928 		ret = true;
1929 		ipencap->dport = nla_get_be16(data[IFLA_GRE_ENCAP_DPORT]);
1930 	}
1931 
1932 	return ret;
1933 }
1934 
1935 static int ip6gre_newlink_common(struct net *src_net, struct net_device *dev,
1936 				 struct nlattr *tb[], struct nlattr *data[],
1937 				 struct netlink_ext_ack *extack)
1938 {
1939 	struct ip6_tnl *nt;
1940 	struct ip_tunnel_encap ipencap;
1941 	int err;
1942 
1943 	nt = netdev_priv(dev);
1944 
1945 	if (ip6gre_netlink_encap_parms(data, &ipencap)) {
1946 		int err = ip6_tnl_encap_setup(nt, &ipencap);
1947 
1948 		if (err < 0)
1949 			return err;
1950 	}
1951 
1952 	if (dev->type == ARPHRD_ETHER && !tb[IFLA_ADDRESS])
1953 		eth_hw_addr_random(dev);
1954 
1955 	nt->dev = dev;
1956 	nt->net = dev_net(dev);
1957 
1958 	err = register_netdevice(dev);
1959 	if (err)
1960 		goto out;
1961 
1962 	if (tb[IFLA_MTU])
1963 		ip6_tnl_change_mtu(dev, nla_get_u32(tb[IFLA_MTU]));
1964 
1965 	dev_hold(dev);
1966 
1967 out:
1968 	return err;
1969 }
1970 
1971 static int ip6gre_newlink(struct net *src_net, struct net_device *dev,
1972 			  struct nlattr *tb[], struct nlattr *data[],
1973 			  struct netlink_ext_ack *extack)
1974 {
1975 	struct ip6_tnl *nt = netdev_priv(dev);
1976 	struct net *net = dev_net(dev);
1977 	struct ip6gre_net *ign;
1978 	int err;
1979 
1980 	ip6gre_netlink_parms(data, &nt->parms);
1981 	ign = net_generic(net, ip6gre_net_id);
1982 
1983 	if (nt->parms.collect_md) {
1984 		if (rtnl_dereference(ign->collect_md_tun))
1985 			return -EEXIST;
1986 	} else {
1987 		if (ip6gre_tunnel_find(net, &nt->parms, dev->type))
1988 			return -EEXIST;
1989 	}
1990 
1991 	err = ip6gre_newlink_common(src_net, dev, tb, data, extack);
1992 	if (!err) {
1993 		ip6gre_tnl_link_config(nt, !tb[IFLA_MTU]);
1994 		ip6gre_tunnel_link_md(ign, nt);
1995 		ip6gre_tunnel_link(net_generic(net, ip6gre_net_id), nt);
1996 	}
1997 	return err;
1998 }
1999 
2000 static struct ip6_tnl *
2001 ip6gre_changelink_common(struct net_device *dev, struct nlattr *tb[],
2002 			 struct nlattr *data[], struct __ip6_tnl_parm *p_p,
2003 			 struct netlink_ext_ack *extack)
2004 {
2005 	struct ip6_tnl *t, *nt = netdev_priv(dev);
2006 	struct net *net = nt->net;
2007 	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
2008 	struct ip_tunnel_encap ipencap;
2009 
2010 	if (dev == ign->fb_tunnel_dev)
2011 		return ERR_PTR(-EINVAL);
2012 
2013 	if (ip6gre_netlink_encap_parms(data, &ipencap)) {
2014 		int err = ip6_tnl_encap_setup(nt, &ipencap);
2015 
2016 		if (err < 0)
2017 			return ERR_PTR(err);
2018 	}
2019 
2020 	ip6gre_netlink_parms(data, p_p);
2021 
2022 	t = ip6gre_tunnel_locate(net, p_p, 0);
2023 
2024 	if (t) {
2025 		if (t->dev != dev)
2026 			return ERR_PTR(-EEXIST);
2027 	} else {
2028 		t = nt;
2029 	}
2030 
2031 	return t;
2032 }
2033 
2034 static int ip6gre_changelink(struct net_device *dev, struct nlattr *tb[],
2035 			     struct nlattr *data[],
2036 			     struct netlink_ext_ack *extack)
2037 {
2038 	struct ip6_tnl *t = netdev_priv(dev);
2039 	struct ip6gre_net *ign = net_generic(t->net, ip6gre_net_id);
2040 	struct __ip6_tnl_parm p;
2041 
2042 	t = ip6gre_changelink_common(dev, tb, data, &p, extack);
2043 	if (IS_ERR(t))
2044 		return PTR_ERR(t);
2045 
2046 	ip6gre_tunnel_unlink_md(ign, t);
2047 	ip6gre_tunnel_unlink(ign, t);
2048 	ip6gre_tnl_change(t, &p, !tb[IFLA_MTU]);
2049 	ip6gre_tunnel_link_md(ign, t);
2050 	ip6gre_tunnel_link(ign, t);
2051 	return 0;
2052 }
2053 
2054 static void ip6gre_dellink(struct net_device *dev, struct list_head *head)
2055 {
2056 	struct net *net = dev_net(dev);
2057 	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
2058 
2059 	if (dev != ign->fb_tunnel_dev)
2060 		unregister_netdevice_queue(dev, head);
2061 }
2062 
2063 static size_t ip6gre_get_size(const struct net_device *dev)
2064 {
2065 	return
2066 		/* IFLA_GRE_LINK */
2067 		nla_total_size(4) +
2068 		/* IFLA_GRE_IFLAGS */
2069 		nla_total_size(2) +
2070 		/* IFLA_GRE_OFLAGS */
2071 		nla_total_size(2) +
2072 		/* IFLA_GRE_IKEY */
2073 		nla_total_size(4) +
2074 		/* IFLA_GRE_OKEY */
2075 		nla_total_size(4) +
2076 		/* IFLA_GRE_LOCAL */
2077 		nla_total_size(sizeof(struct in6_addr)) +
2078 		/* IFLA_GRE_REMOTE */
2079 		nla_total_size(sizeof(struct in6_addr)) +
2080 		/* IFLA_GRE_TTL */
2081 		nla_total_size(1) +
2082 		/* IFLA_GRE_ENCAP_LIMIT */
2083 		nla_total_size(1) +
2084 		/* IFLA_GRE_FLOWINFO */
2085 		nla_total_size(4) +
2086 		/* IFLA_GRE_FLAGS */
2087 		nla_total_size(4) +
2088 		/* IFLA_GRE_ENCAP_TYPE */
2089 		nla_total_size(2) +
2090 		/* IFLA_GRE_ENCAP_FLAGS */
2091 		nla_total_size(2) +
2092 		/* IFLA_GRE_ENCAP_SPORT */
2093 		nla_total_size(2) +
2094 		/* IFLA_GRE_ENCAP_DPORT */
2095 		nla_total_size(2) +
2096 		/* IFLA_GRE_COLLECT_METADATA */
2097 		nla_total_size(0) +
2098 		/* IFLA_GRE_FWMARK */
2099 		nla_total_size(4) +
2100 		/* IFLA_GRE_ERSPAN_INDEX */
2101 		nla_total_size(4) +
2102 		0;
2103 }
2104 
2105 static int ip6gre_fill_info(struct sk_buff *skb, const struct net_device *dev)
2106 {
2107 	struct ip6_tnl *t = netdev_priv(dev);
2108 	struct __ip6_tnl_parm *p = &t->parms;
2109 	__be16 o_flags = p->o_flags;
2110 
2111 	if (p->erspan_ver == 1 || p->erspan_ver == 2) {
2112 		if (!p->collect_md)
2113 			o_flags |= TUNNEL_KEY;
2114 
2115 		if (nla_put_u8(skb, IFLA_GRE_ERSPAN_VER, p->erspan_ver))
2116 			goto nla_put_failure;
2117 
2118 		if (p->erspan_ver == 1) {
2119 			if (nla_put_u32(skb, IFLA_GRE_ERSPAN_INDEX, p->index))
2120 				goto nla_put_failure;
2121 		} else {
2122 			if (nla_put_u8(skb, IFLA_GRE_ERSPAN_DIR, p->dir))
2123 				goto nla_put_failure;
2124 			if (nla_put_u16(skb, IFLA_GRE_ERSPAN_HWID, p->hwid))
2125 				goto nla_put_failure;
2126 		}
2127 	}
2128 
2129 	if (nla_put_u32(skb, IFLA_GRE_LINK, p->link) ||
2130 	    nla_put_be16(skb, IFLA_GRE_IFLAGS,
2131 			 gre_tnl_flags_to_gre_flags(p->i_flags)) ||
2132 	    nla_put_be16(skb, IFLA_GRE_OFLAGS,
2133 			 gre_tnl_flags_to_gre_flags(o_flags)) ||
2134 	    nla_put_be32(skb, IFLA_GRE_IKEY, p->i_key) ||
2135 	    nla_put_be32(skb, IFLA_GRE_OKEY, p->o_key) ||
2136 	    nla_put_in6_addr(skb, IFLA_GRE_LOCAL, &p->laddr) ||
2137 	    nla_put_in6_addr(skb, IFLA_GRE_REMOTE, &p->raddr) ||
2138 	    nla_put_u8(skb, IFLA_GRE_TTL, p->hop_limit) ||
2139 	    nla_put_u8(skb, IFLA_GRE_ENCAP_LIMIT, p->encap_limit) ||
2140 	    nla_put_be32(skb, IFLA_GRE_FLOWINFO, p->flowinfo) ||
2141 	    nla_put_u32(skb, IFLA_GRE_FLAGS, p->flags) ||
2142 	    nla_put_u32(skb, IFLA_GRE_FWMARK, p->fwmark))
2143 		goto nla_put_failure;
2144 
2145 	if (nla_put_u16(skb, IFLA_GRE_ENCAP_TYPE,
2146 			t->encap.type) ||
2147 	    nla_put_be16(skb, IFLA_GRE_ENCAP_SPORT,
2148 			 t->encap.sport) ||
2149 	    nla_put_be16(skb, IFLA_GRE_ENCAP_DPORT,
2150 			 t->encap.dport) ||
2151 	    nla_put_u16(skb, IFLA_GRE_ENCAP_FLAGS,
2152 			t->encap.flags))
2153 		goto nla_put_failure;
2154 
2155 	if (p->collect_md) {
2156 		if (nla_put_flag(skb, IFLA_GRE_COLLECT_METADATA))
2157 			goto nla_put_failure;
2158 	}
2159 
2160 	return 0;
2161 
2162 nla_put_failure:
2163 	return -EMSGSIZE;
2164 }
2165 
2166 static const struct nla_policy ip6gre_policy[IFLA_GRE_MAX + 1] = {
2167 	[IFLA_GRE_LINK]        = { .type = NLA_U32 },
2168 	[IFLA_GRE_IFLAGS]      = { .type = NLA_U16 },
2169 	[IFLA_GRE_OFLAGS]      = { .type = NLA_U16 },
2170 	[IFLA_GRE_IKEY]        = { .type = NLA_U32 },
2171 	[IFLA_GRE_OKEY]        = { .type = NLA_U32 },
2172 	[IFLA_GRE_LOCAL]       = { .len = FIELD_SIZEOF(struct ipv6hdr, saddr) },
2173 	[IFLA_GRE_REMOTE]      = { .len = FIELD_SIZEOF(struct ipv6hdr, daddr) },
2174 	[IFLA_GRE_TTL]         = { .type = NLA_U8 },
2175 	[IFLA_GRE_ENCAP_LIMIT] = { .type = NLA_U8 },
2176 	[IFLA_GRE_FLOWINFO]    = { .type = NLA_U32 },
2177 	[IFLA_GRE_FLAGS]       = { .type = NLA_U32 },
2178 	[IFLA_GRE_ENCAP_TYPE]   = { .type = NLA_U16 },
2179 	[IFLA_GRE_ENCAP_FLAGS]  = { .type = NLA_U16 },
2180 	[IFLA_GRE_ENCAP_SPORT]  = { .type = NLA_U16 },
2181 	[IFLA_GRE_ENCAP_DPORT]  = { .type = NLA_U16 },
2182 	[IFLA_GRE_COLLECT_METADATA] = { .type = NLA_FLAG },
2183 	[IFLA_GRE_FWMARK]       = { .type = NLA_U32 },
2184 	[IFLA_GRE_ERSPAN_INDEX] = { .type = NLA_U32 },
2185 	[IFLA_GRE_ERSPAN_VER]	= { .type = NLA_U8 },
2186 	[IFLA_GRE_ERSPAN_DIR]	= { .type = NLA_U8 },
2187 	[IFLA_GRE_ERSPAN_HWID]	= { .type = NLA_U16 },
2188 };
2189 
2190 static void ip6erspan_tap_setup(struct net_device *dev)
2191 {
2192 	ether_setup(dev);
2193 
2194 	dev->netdev_ops = &ip6erspan_netdev_ops;
2195 	dev->needs_free_netdev = true;
2196 	dev->priv_destructor = ip6gre_dev_free;
2197 
2198 	dev->features |= NETIF_F_NETNS_LOCAL;
2199 	dev->priv_flags &= ~IFF_TX_SKB_SHARING;
2200 	dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
2201 	netif_keep_dst(dev);
2202 }
2203 
2204 static int ip6erspan_newlink(struct net *src_net, struct net_device *dev,
2205 			     struct nlattr *tb[], struct nlattr *data[],
2206 			     struct netlink_ext_ack *extack)
2207 {
2208 	struct ip6_tnl *nt = netdev_priv(dev);
2209 	struct net *net = dev_net(dev);
2210 	struct ip6gre_net *ign;
2211 	int err;
2212 
2213 	ip6gre_netlink_parms(data, &nt->parms);
2214 	ip6erspan_set_version(data, &nt->parms);
2215 	ign = net_generic(net, ip6gre_net_id);
2216 
2217 	if (nt->parms.collect_md) {
2218 		if (rtnl_dereference(ign->collect_md_tun_erspan))
2219 			return -EEXIST;
2220 	} else {
2221 		if (ip6gre_tunnel_find(net, &nt->parms, dev->type))
2222 			return -EEXIST;
2223 	}
2224 
2225 	err = ip6gre_newlink_common(src_net, dev, tb, data, extack);
2226 	if (!err) {
2227 		ip6erspan_tnl_link_config(nt, !tb[IFLA_MTU]);
2228 		ip6erspan_tunnel_link_md(ign, nt);
2229 		ip6gre_tunnel_link(net_generic(net, ip6gre_net_id), nt);
2230 	}
2231 	return err;
2232 }
2233 
2234 static void ip6erspan_tnl_link_config(struct ip6_tnl *t, int set_mtu)
2235 {
2236 	ip6gre_tnl_link_config_common(t);
2237 	ip6gre_tnl_link_config_route(t, set_mtu, ip6erspan_calc_hlen(t));
2238 }
2239 
2240 static int ip6erspan_tnl_change(struct ip6_tnl *t,
2241 				const struct __ip6_tnl_parm *p, int set_mtu)
2242 {
2243 	ip6gre_tnl_copy_tnl_parm(t, p);
2244 	ip6erspan_tnl_link_config(t, set_mtu);
2245 	return 0;
2246 }
2247 
2248 static int ip6erspan_changelink(struct net_device *dev, struct nlattr *tb[],
2249 				struct nlattr *data[],
2250 				struct netlink_ext_ack *extack)
2251 {
2252 	struct ip6gre_net *ign = net_generic(dev_net(dev), ip6gre_net_id);
2253 	struct __ip6_tnl_parm p;
2254 	struct ip6_tnl *t;
2255 
2256 	t = ip6gre_changelink_common(dev, tb, data, &p, extack);
2257 	if (IS_ERR(t))
2258 		return PTR_ERR(t);
2259 
2260 	ip6erspan_set_version(data, &p);
2261 	ip6gre_tunnel_unlink_md(ign, t);
2262 	ip6gre_tunnel_unlink(ign, t);
2263 	ip6erspan_tnl_change(t, &p, !tb[IFLA_MTU]);
2264 	ip6erspan_tunnel_link_md(ign, t);
2265 	ip6gre_tunnel_link(ign, t);
2266 	return 0;
2267 }
2268 
2269 static struct rtnl_link_ops ip6gre_link_ops __read_mostly = {
2270 	.kind		= "ip6gre",
2271 	.maxtype	= IFLA_GRE_MAX,
2272 	.policy		= ip6gre_policy,
2273 	.priv_size	= sizeof(struct ip6_tnl),
2274 	.setup		= ip6gre_tunnel_setup,
2275 	.validate	= ip6gre_tunnel_validate,
2276 	.newlink	= ip6gre_newlink,
2277 	.changelink	= ip6gre_changelink,
2278 	.dellink	= ip6gre_dellink,
2279 	.get_size	= ip6gre_get_size,
2280 	.fill_info	= ip6gre_fill_info,
2281 	.get_link_net	= ip6_tnl_get_link_net,
2282 };
2283 
2284 static struct rtnl_link_ops ip6gre_tap_ops __read_mostly = {
2285 	.kind		= "ip6gretap",
2286 	.maxtype	= IFLA_GRE_MAX,
2287 	.policy		= ip6gre_policy,
2288 	.priv_size	= sizeof(struct ip6_tnl),
2289 	.setup		= ip6gre_tap_setup,
2290 	.validate	= ip6gre_tap_validate,
2291 	.newlink	= ip6gre_newlink,
2292 	.changelink	= ip6gre_changelink,
2293 	.get_size	= ip6gre_get_size,
2294 	.fill_info	= ip6gre_fill_info,
2295 	.get_link_net	= ip6_tnl_get_link_net,
2296 };
2297 
2298 static struct rtnl_link_ops ip6erspan_tap_ops __read_mostly = {
2299 	.kind		= "ip6erspan",
2300 	.maxtype	= IFLA_GRE_MAX,
2301 	.policy		= ip6gre_policy,
2302 	.priv_size	= sizeof(struct ip6_tnl),
2303 	.setup		= ip6erspan_tap_setup,
2304 	.validate	= ip6erspan_tap_validate,
2305 	.newlink	= ip6erspan_newlink,
2306 	.changelink	= ip6erspan_changelink,
2307 	.get_size	= ip6gre_get_size,
2308 	.fill_info	= ip6gre_fill_info,
2309 	.get_link_net	= ip6_tnl_get_link_net,
2310 };
2311 
2312 /*
2313  *	And now the modules code and kernel interface.
2314  */
2315 
2316 static int __init ip6gre_init(void)
2317 {
2318 	int err;
2319 
2320 	pr_info("GRE over IPv6 tunneling driver\n");
2321 
2322 	err = register_pernet_device(&ip6gre_net_ops);
2323 	if (err < 0)
2324 		return err;
2325 
2326 	err = inet6_add_protocol(&ip6gre_protocol, IPPROTO_GRE);
2327 	if (err < 0) {
2328 		pr_info("%s: can't add protocol\n", __func__);
2329 		goto add_proto_failed;
2330 	}
2331 
2332 	err = rtnl_link_register(&ip6gre_link_ops);
2333 	if (err < 0)
2334 		goto rtnl_link_failed;
2335 
2336 	err = rtnl_link_register(&ip6gre_tap_ops);
2337 	if (err < 0)
2338 		goto tap_ops_failed;
2339 
2340 	err = rtnl_link_register(&ip6erspan_tap_ops);
2341 	if (err < 0)
2342 		goto erspan_link_failed;
2343 
2344 out:
2345 	return err;
2346 
2347 erspan_link_failed:
2348 	rtnl_link_unregister(&ip6gre_tap_ops);
2349 tap_ops_failed:
2350 	rtnl_link_unregister(&ip6gre_link_ops);
2351 rtnl_link_failed:
2352 	inet6_del_protocol(&ip6gre_protocol, IPPROTO_GRE);
2353 add_proto_failed:
2354 	unregister_pernet_device(&ip6gre_net_ops);
2355 	goto out;
2356 }
2357 
2358 static void __exit ip6gre_fini(void)
2359 {
2360 	rtnl_link_unregister(&ip6gre_tap_ops);
2361 	rtnl_link_unregister(&ip6gre_link_ops);
2362 	rtnl_link_unregister(&ip6erspan_tap_ops);
2363 	inet6_del_protocol(&ip6gre_protocol, IPPROTO_GRE);
2364 	unregister_pernet_device(&ip6gre_net_ops);
2365 }
2366 
2367 module_init(ip6gre_init);
2368 module_exit(ip6gre_fini);
2369 MODULE_LICENSE("GPL");
2370 MODULE_AUTHOR("D. Kozlov (xeb@mail.ru)");
2371 MODULE_DESCRIPTION("GRE over IPv6 tunneling device");
2372 MODULE_ALIAS_RTNL_LINK("ip6gre");
2373 MODULE_ALIAS_RTNL_LINK("ip6gretap");
2374 MODULE_ALIAS_RTNL_LINK("ip6erspan");
2375 MODULE_ALIAS_NETDEV("ip6gre0");
2376