xref: /openbmc/linux/net/ipv6/ip6_gre.c (revision f05643a0)
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 		strlcpy(name, parms->name, IFNAMSIZ);
364 	} else {
365 		strcpy(name, "ip6gre%d");
366 	}
367 	dev = alloc_netdev(sizeof(*t), name, NET_NAME_UNKNOWN,
368 			   ip6gre_tunnel_setup);
369 	if (!dev)
370 		return NULL;
371 
372 	dev_net_set(dev, net);
373 
374 	nt = netdev_priv(dev);
375 	nt->parms = *parms;
376 	dev->rtnl_link_ops = &ip6gre_link_ops;
377 
378 	nt->dev = dev;
379 	nt->net = dev_net(dev);
380 
381 	if (register_netdevice(dev) < 0)
382 		goto failed_free;
383 
384 	ip6gre_tnl_link_config(nt, 1);
385 	ip6gre_tunnel_link(ign, nt);
386 	return nt;
387 
388 failed_free:
389 	free_netdev(dev);
390 	return NULL;
391 }
392 
393 static void ip6erspan_tunnel_uninit(struct net_device *dev)
394 {
395 	struct ip6_tnl *t = netdev_priv(dev);
396 	struct ip6gre_net *ign = net_generic(t->net, ip6gre_net_id);
397 
398 	ip6erspan_tunnel_unlink_md(ign, t);
399 	ip6gre_tunnel_unlink(ign, t);
400 	dst_cache_reset(&t->dst_cache);
401 	netdev_put(dev, &t->dev_tracker);
402 }
403 
404 static void ip6gre_tunnel_uninit(struct net_device *dev)
405 {
406 	struct ip6_tnl *t = netdev_priv(dev);
407 	struct ip6gre_net *ign = net_generic(t->net, ip6gre_net_id);
408 
409 	ip6gre_tunnel_unlink_md(ign, t);
410 	ip6gre_tunnel_unlink(ign, t);
411 	if (ign->fb_tunnel_dev == dev)
412 		WRITE_ONCE(ign->fb_tunnel_dev, NULL);
413 	dst_cache_reset(&t->dst_cache);
414 	netdev_put(dev, &t->dev_tracker);
415 }
416 
417 
418 static int ip6gre_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
419 		       u8 type, u8 code, int offset, __be32 info)
420 {
421 	struct net *net = dev_net(skb->dev);
422 	const struct ipv6hdr *ipv6h;
423 	struct tnl_ptk_info tpi;
424 	struct ip6_tnl *t;
425 
426 	if (gre_parse_header(skb, &tpi, NULL, htons(ETH_P_IPV6),
427 			     offset) < 0)
428 		return -EINVAL;
429 
430 	ipv6h = (const struct ipv6hdr *)skb->data;
431 	t = ip6gre_tunnel_lookup(skb->dev, &ipv6h->daddr, &ipv6h->saddr,
432 				 tpi.key, tpi.proto);
433 	if (!t)
434 		return -ENOENT;
435 
436 	switch (type) {
437 	case ICMPV6_DEST_UNREACH:
438 		net_dbg_ratelimited("%s: Path to destination invalid or inactive!\n",
439 				    t->parms.name);
440 		if (code != ICMPV6_PORT_UNREACH)
441 			break;
442 		return 0;
443 	case ICMPV6_TIME_EXCEED:
444 		if (code == ICMPV6_EXC_HOPLIMIT) {
445 			net_dbg_ratelimited("%s: Too small hop limit or routing loop in tunnel!\n",
446 					    t->parms.name);
447 			break;
448 		}
449 		return 0;
450 	case ICMPV6_PARAMPROB: {
451 		struct ipv6_tlv_tnl_enc_lim *tel;
452 		__u32 teli;
453 
454 		teli = 0;
455 		if (code == ICMPV6_HDR_FIELD)
456 			teli = ip6_tnl_parse_tlv_enc_lim(skb, skb->data);
457 
458 		if (teli && teli == be32_to_cpu(info) - 2) {
459 			tel = (struct ipv6_tlv_tnl_enc_lim *) &skb->data[teli];
460 			if (tel->encap_limit == 0) {
461 				net_dbg_ratelimited("%s: Too small encapsulation limit or routing loop in tunnel!\n",
462 						    t->parms.name);
463 			}
464 		} else {
465 			net_dbg_ratelimited("%s: Recipient unable to parse tunneled packet!\n",
466 					    t->parms.name);
467 		}
468 		return 0;
469 	}
470 	case ICMPV6_PKT_TOOBIG:
471 		ip6_update_pmtu(skb, net, info, 0, 0, sock_net_uid(net, NULL));
472 		return 0;
473 	case NDISC_REDIRECT:
474 		ip6_redirect(skb, net, skb->dev->ifindex, 0,
475 			     sock_net_uid(net, NULL));
476 		return 0;
477 	}
478 
479 	if (time_before(jiffies, t->err_time + IP6TUNNEL_ERR_TIMEO))
480 		t->err_count++;
481 	else
482 		t->err_count = 1;
483 	t->err_time = jiffies;
484 
485 	return 0;
486 }
487 
488 static int ip6gre_rcv(struct sk_buff *skb, const struct tnl_ptk_info *tpi)
489 {
490 	const struct ipv6hdr *ipv6h;
491 	struct ip6_tnl *tunnel;
492 
493 	ipv6h = ipv6_hdr(skb);
494 	tunnel = ip6gre_tunnel_lookup(skb->dev,
495 				      &ipv6h->saddr, &ipv6h->daddr, tpi->key,
496 				      tpi->proto);
497 	if (tunnel) {
498 		if (tunnel->parms.collect_md) {
499 			struct metadata_dst *tun_dst;
500 			__be64 tun_id;
501 			__be16 flags;
502 
503 			flags = tpi->flags;
504 			tun_id = key32_to_tunnel_id(tpi->key);
505 
506 			tun_dst = ipv6_tun_rx_dst(skb, flags, tun_id, 0);
507 			if (!tun_dst)
508 				return PACKET_REJECT;
509 
510 			ip6_tnl_rcv(tunnel, skb, tpi, tun_dst, log_ecn_error);
511 		} else {
512 			ip6_tnl_rcv(tunnel, skb, tpi, NULL, log_ecn_error);
513 		}
514 
515 		return PACKET_RCVD;
516 	}
517 
518 	return PACKET_REJECT;
519 }
520 
521 static int ip6erspan_rcv(struct sk_buff *skb,
522 			 struct tnl_ptk_info *tpi,
523 			 int gre_hdr_len)
524 {
525 	struct erspan_base_hdr *ershdr;
526 	const struct ipv6hdr *ipv6h;
527 	struct erspan_md2 *md2;
528 	struct ip6_tnl *tunnel;
529 	u8 ver;
530 
531 	ipv6h = ipv6_hdr(skb);
532 	ershdr = (struct erspan_base_hdr *)skb->data;
533 	ver = ershdr->ver;
534 
535 	tunnel = ip6gre_tunnel_lookup(skb->dev,
536 				      &ipv6h->saddr, &ipv6h->daddr, tpi->key,
537 				      tpi->proto);
538 	if (tunnel) {
539 		int len = erspan_hdr_len(ver);
540 
541 		if (unlikely(!pskb_may_pull(skb, len)))
542 			return PACKET_REJECT;
543 
544 		if (__iptunnel_pull_header(skb, len,
545 					   htons(ETH_P_TEB),
546 					   false, false) < 0)
547 			return PACKET_REJECT;
548 
549 		if (tunnel->parms.collect_md) {
550 			struct erspan_metadata *pkt_md, *md;
551 			struct metadata_dst *tun_dst;
552 			struct ip_tunnel_info *info;
553 			unsigned char *gh;
554 			__be64 tun_id;
555 			__be16 flags;
556 
557 			tpi->flags |= TUNNEL_KEY;
558 			flags = tpi->flags;
559 			tun_id = key32_to_tunnel_id(tpi->key);
560 
561 			tun_dst = ipv6_tun_rx_dst(skb, flags, tun_id,
562 						  sizeof(*md));
563 			if (!tun_dst)
564 				return PACKET_REJECT;
565 
566 			/* skb can be uncloned in __iptunnel_pull_header, so
567 			 * old pkt_md is no longer valid and we need to reset
568 			 * it
569 			 */
570 			gh = skb_network_header(skb) +
571 			     skb_network_header_len(skb);
572 			pkt_md = (struct erspan_metadata *)(gh + gre_hdr_len +
573 							    sizeof(*ershdr));
574 			info = &tun_dst->u.tun_info;
575 			md = ip_tunnel_info_opts(info);
576 			md->version = ver;
577 			md2 = &md->u.md2;
578 			memcpy(md2, pkt_md, ver == 1 ? ERSPAN_V1_MDSIZE :
579 						       ERSPAN_V2_MDSIZE);
580 			info->key.tun_flags |= TUNNEL_ERSPAN_OPT;
581 			info->options_len = sizeof(*md);
582 
583 			ip6_tnl_rcv(tunnel, skb, tpi, tun_dst, log_ecn_error);
584 
585 		} else {
586 			ip6_tnl_rcv(tunnel, skb, tpi, NULL, log_ecn_error);
587 		}
588 
589 		return PACKET_RCVD;
590 	}
591 
592 	return PACKET_REJECT;
593 }
594 
595 static int gre_rcv(struct sk_buff *skb)
596 {
597 	struct tnl_ptk_info tpi;
598 	bool csum_err = false;
599 	int hdr_len;
600 
601 	hdr_len = gre_parse_header(skb, &tpi, &csum_err, htons(ETH_P_IPV6), 0);
602 	if (hdr_len < 0)
603 		goto drop;
604 
605 	if (iptunnel_pull_header(skb, hdr_len, tpi.proto, false))
606 		goto drop;
607 
608 	if (unlikely(tpi.proto == htons(ETH_P_ERSPAN) ||
609 		     tpi.proto == htons(ETH_P_ERSPAN2))) {
610 		if (ip6erspan_rcv(skb, &tpi, hdr_len) == PACKET_RCVD)
611 			return 0;
612 		goto out;
613 	}
614 
615 	if (ip6gre_rcv(skb, &tpi) == PACKET_RCVD)
616 		return 0;
617 
618 out:
619 	icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0);
620 drop:
621 	kfree_skb(skb);
622 	return 0;
623 }
624 
625 static int gre_handle_offloads(struct sk_buff *skb, bool csum)
626 {
627 	return iptunnel_handle_offloads(skb,
628 					csum ? SKB_GSO_GRE_CSUM : SKB_GSO_GRE);
629 }
630 
631 static void prepare_ip6gre_xmit_ipv4(struct sk_buff *skb,
632 				     struct net_device *dev,
633 				     struct flowi6 *fl6, __u8 *dsfield,
634 				     int *encap_limit)
635 {
636 	const struct iphdr *iph = ip_hdr(skb);
637 	struct ip6_tnl *t = netdev_priv(dev);
638 
639 	if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
640 		*encap_limit = t->parms.encap_limit;
641 
642 	memcpy(fl6, &t->fl.u.ip6, sizeof(*fl6));
643 
644 	if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
645 		*dsfield = ipv4_get_dsfield(iph);
646 	else
647 		*dsfield = ip6_tclass(t->parms.flowinfo);
648 
649 	if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
650 		fl6->flowi6_mark = skb->mark;
651 	else
652 		fl6->flowi6_mark = t->parms.fwmark;
653 
654 	fl6->flowi6_uid = sock_net_uid(dev_net(dev), NULL);
655 }
656 
657 static int prepare_ip6gre_xmit_ipv6(struct sk_buff *skb,
658 				    struct net_device *dev,
659 				    struct flowi6 *fl6, __u8 *dsfield,
660 				    int *encap_limit)
661 {
662 	struct ipv6hdr *ipv6h;
663 	struct ip6_tnl *t = netdev_priv(dev);
664 	__u16 offset;
665 
666 	offset = ip6_tnl_parse_tlv_enc_lim(skb, skb_network_header(skb));
667 	/* ip6_tnl_parse_tlv_enc_lim() might have reallocated skb->head */
668 	ipv6h = ipv6_hdr(skb);
669 
670 	if (offset > 0) {
671 		struct ipv6_tlv_tnl_enc_lim *tel;
672 
673 		tel = (struct ipv6_tlv_tnl_enc_lim *)&skb_network_header(skb)[offset];
674 		if (tel->encap_limit == 0) {
675 			icmpv6_ndo_send(skb, ICMPV6_PARAMPROB,
676 					ICMPV6_HDR_FIELD, offset + 2);
677 			return -1;
678 		}
679 		*encap_limit = tel->encap_limit - 1;
680 	} else if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) {
681 		*encap_limit = t->parms.encap_limit;
682 	}
683 
684 	memcpy(fl6, &t->fl.u.ip6, sizeof(*fl6));
685 
686 	if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
687 		*dsfield = ipv6_get_dsfield(ipv6h);
688 	else
689 		*dsfield = ip6_tclass(t->parms.flowinfo);
690 
691 	if (t->parms.flags & IP6_TNL_F_USE_ORIG_FLOWLABEL)
692 		fl6->flowlabel |= ip6_flowlabel(ipv6h);
693 
694 	if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
695 		fl6->flowi6_mark = skb->mark;
696 	else
697 		fl6->flowi6_mark = t->parms.fwmark;
698 
699 	fl6->flowi6_uid = sock_net_uid(dev_net(dev), NULL);
700 
701 	return 0;
702 }
703 
704 static struct ip_tunnel_info *skb_tunnel_info_txcheck(struct sk_buff *skb)
705 {
706 	struct ip_tunnel_info *tun_info;
707 
708 	tun_info = skb_tunnel_info(skb);
709 	if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX)))
710 		return ERR_PTR(-EINVAL);
711 
712 	return tun_info;
713 }
714 
715 static netdev_tx_t __gre6_xmit(struct sk_buff *skb,
716 			       struct net_device *dev, __u8 dsfield,
717 			       struct flowi6 *fl6, int encap_limit,
718 			       __u32 *pmtu, __be16 proto)
719 {
720 	struct ip6_tnl *tunnel = netdev_priv(dev);
721 	__be16 protocol;
722 	__be16 flags;
723 
724 	if (dev->type == ARPHRD_ETHER)
725 		IPCB(skb)->flags = 0;
726 
727 	if (dev->header_ops && dev->type == ARPHRD_IP6GRE)
728 		fl6->daddr = ((struct ipv6hdr *)skb->data)->daddr;
729 	else
730 		fl6->daddr = tunnel->parms.raddr;
731 
732 	/* Push GRE header. */
733 	protocol = (dev->type == ARPHRD_ETHER) ? htons(ETH_P_TEB) : proto;
734 
735 	if (tunnel->parms.collect_md) {
736 		struct ip_tunnel_info *tun_info;
737 		const struct ip_tunnel_key *key;
738 		int tun_hlen;
739 
740 		tun_info = skb_tunnel_info_txcheck(skb);
741 		if (IS_ERR(tun_info) ||
742 		    unlikely(ip_tunnel_info_af(tun_info) != AF_INET6))
743 			return -EINVAL;
744 
745 		key = &tun_info->key;
746 		memset(fl6, 0, sizeof(*fl6));
747 		fl6->flowi6_proto = IPPROTO_GRE;
748 		fl6->daddr = key->u.ipv6.dst;
749 		fl6->flowlabel = key->label;
750 		fl6->flowi6_uid = sock_net_uid(dev_net(dev), NULL);
751 		fl6->fl6_gre_key = tunnel_id_to_key32(key->tun_id);
752 
753 		dsfield = key->tos;
754 		flags = key->tun_flags &
755 			(TUNNEL_CSUM | TUNNEL_KEY | TUNNEL_SEQ);
756 		tun_hlen = gre_calc_hlen(flags);
757 
758 		if (skb_cow_head(skb, dev->needed_headroom ?: tun_hlen + tunnel->encap_hlen))
759 			return -ENOMEM;
760 
761 		gre_build_header(skb, tun_hlen,
762 				 flags, protocol,
763 				 tunnel_id_to_key32(tun_info->key.tun_id),
764 				 (flags & TUNNEL_SEQ) ? htonl(atomic_fetch_inc(&tunnel->o_seqno))
765 						      : 0);
766 
767 	} else {
768 		if (skb_cow_head(skb, dev->needed_headroom ?: tunnel->hlen))
769 			return -ENOMEM;
770 
771 		flags = tunnel->parms.o_flags;
772 
773 		gre_build_header(skb, tunnel->tun_hlen, flags,
774 				 protocol, tunnel->parms.o_key,
775 				 (flags & TUNNEL_SEQ) ? htonl(atomic_fetch_inc(&tunnel->o_seqno))
776 						      : 0);
777 	}
778 
779 	return ip6_tnl_xmit(skb, dev, dsfield, fl6, encap_limit, pmtu,
780 			    NEXTHDR_GRE);
781 }
782 
783 static inline int ip6gre_xmit_ipv4(struct sk_buff *skb, struct net_device *dev)
784 {
785 	struct ip6_tnl *t = netdev_priv(dev);
786 	int encap_limit = -1;
787 	struct flowi6 fl6;
788 	__u8 dsfield = 0;
789 	__u32 mtu;
790 	int err;
791 
792 	memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
793 
794 	if (!t->parms.collect_md)
795 		prepare_ip6gre_xmit_ipv4(skb, dev, &fl6,
796 					 &dsfield, &encap_limit);
797 
798 	err = gre_handle_offloads(skb, !!(t->parms.o_flags & TUNNEL_CSUM));
799 	if (err)
800 		return -1;
801 
802 	err = __gre6_xmit(skb, dev, dsfield, &fl6, encap_limit, &mtu,
803 			  skb->protocol);
804 	if (err != 0) {
805 		/* XXX: send ICMP error even if DF is not set. */
806 		if (err == -EMSGSIZE)
807 			icmp_ndo_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
808 				      htonl(mtu));
809 		return -1;
810 	}
811 
812 	return 0;
813 }
814 
815 static inline int ip6gre_xmit_ipv6(struct sk_buff *skb, struct net_device *dev)
816 {
817 	struct ip6_tnl *t = netdev_priv(dev);
818 	struct ipv6hdr *ipv6h = ipv6_hdr(skb);
819 	int encap_limit = -1;
820 	struct flowi6 fl6;
821 	__u8 dsfield = 0;
822 	__u32 mtu;
823 	int err;
824 
825 	if (ipv6_addr_equal(&t->parms.raddr, &ipv6h->saddr))
826 		return -1;
827 
828 	if (!t->parms.collect_md &&
829 	    prepare_ip6gre_xmit_ipv6(skb, dev, &fl6, &dsfield, &encap_limit))
830 		return -1;
831 
832 	if (gre_handle_offloads(skb, !!(t->parms.o_flags & TUNNEL_CSUM)))
833 		return -1;
834 
835 	err = __gre6_xmit(skb, dev, dsfield, &fl6, encap_limit,
836 			  &mtu, skb->protocol);
837 	if (err != 0) {
838 		if (err == -EMSGSIZE)
839 			icmpv6_ndo_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
840 		return -1;
841 	}
842 
843 	return 0;
844 }
845 
846 /**
847  * ip6gre_tnl_addr_conflict - compare packet addresses to tunnel's own
848  *   @t: the outgoing tunnel device
849  *   @hdr: IPv6 header from the incoming packet
850  *
851  * Description:
852  *   Avoid trivial tunneling loop by checking that tunnel exit-point
853  *   doesn't match source of incoming packet.
854  *
855  * Return:
856  *   1 if conflict,
857  *   0 else
858  **/
859 
860 static inline bool ip6gre_tnl_addr_conflict(const struct ip6_tnl *t,
861 	const struct ipv6hdr *hdr)
862 {
863 	return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr);
864 }
865 
866 static int ip6gre_xmit_other(struct sk_buff *skb, struct net_device *dev)
867 {
868 	struct ip6_tnl *t = netdev_priv(dev);
869 	int encap_limit = -1;
870 	struct flowi6 fl6;
871 	__u32 mtu;
872 	int err;
873 
874 	if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
875 		encap_limit = t->parms.encap_limit;
876 
877 	if (!t->parms.collect_md)
878 		memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6));
879 
880 	err = gre_handle_offloads(skb, !!(t->parms.o_flags & TUNNEL_CSUM));
881 	if (err)
882 		return err;
883 
884 	err = __gre6_xmit(skb, dev, 0, &fl6, encap_limit, &mtu, skb->protocol);
885 
886 	return err;
887 }
888 
889 static netdev_tx_t ip6gre_tunnel_xmit(struct sk_buff *skb,
890 	struct net_device *dev)
891 {
892 	struct ip6_tnl *t = netdev_priv(dev);
893 	struct net_device_stats *stats = &t->dev->stats;
894 	int ret;
895 
896 	if (!pskb_inet_may_pull(skb))
897 		goto tx_err;
898 
899 	if (!ip6_tnl_xmit_ctl(t, &t->parms.laddr, &t->parms.raddr))
900 		goto tx_err;
901 
902 	switch (skb->protocol) {
903 	case htons(ETH_P_IP):
904 		ret = ip6gre_xmit_ipv4(skb, dev);
905 		break;
906 	case htons(ETH_P_IPV6):
907 		ret = ip6gre_xmit_ipv6(skb, dev);
908 		break;
909 	default:
910 		ret = ip6gre_xmit_other(skb, dev);
911 		break;
912 	}
913 
914 	if (ret < 0)
915 		goto tx_err;
916 
917 	return NETDEV_TX_OK;
918 
919 tx_err:
920 	if (!t->parms.collect_md || !IS_ERR(skb_tunnel_info_txcheck(skb)))
921 		stats->tx_errors++;
922 	stats->tx_dropped++;
923 	kfree_skb(skb);
924 	return NETDEV_TX_OK;
925 }
926 
927 static netdev_tx_t ip6erspan_tunnel_xmit(struct sk_buff *skb,
928 					 struct net_device *dev)
929 {
930 	struct ip_tunnel_info *tun_info = NULL;
931 	struct ip6_tnl *t = netdev_priv(dev);
932 	struct dst_entry *dst = skb_dst(skb);
933 	struct net_device_stats *stats;
934 	bool truncate = false;
935 	int encap_limit = -1;
936 	__u8 dsfield = false;
937 	struct flowi6 fl6;
938 	int err = -EINVAL;
939 	__be16 proto;
940 	__u32 mtu;
941 	int nhoff;
942 
943 	if (!pskb_inet_may_pull(skb))
944 		goto tx_err;
945 
946 	if (!ip6_tnl_xmit_ctl(t, &t->parms.laddr, &t->parms.raddr))
947 		goto tx_err;
948 
949 	if (gre_handle_offloads(skb, false))
950 		goto tx_err;
951 
952 	if (skb->len > dev->mtu + dev->hard_header_len) {
953 		pskb_trim(skb, dev->mtu + dev->hard_header_len);
954 		truncate = true;
955 	}
956 
957 	nhoff = skb_network_header(skb) - skb_mac_header(skb);
958 	if (skb->protocol == htons(ETH_P_IP) &&
959 	    (ntohs(ip_hdr(skb)->tot_len) > skb->len - nhoff))
960 		truncate = true;
961 
962 	if (skb->protocol == htons(ETH_P_IPV6)) {
963 		int thoff;
964 
965 		if (skb_transport_header_was_set(skb))
966 			thoff = skb_transport_header(skb) - skb_mac_header(skb);
967 		else
968 			thoff = nhoff + sizeof(struct ipv6hdr);
969 		if (ntohs(ipv6_hdr(skb)->payload_len) > skb->len - thoff)
970 			truncate = true;
971 	}
972 
973 	if (skb_cow_head(skb, dev->needed_headroom ?: t->hlen))
974 		goto tx_err;
975 
976 	t->parms.o_flags &= ~TUNNEL_KEY;
977 	IPCB(skb)->flags = 0;
978 
979 	/* For collect_md mode, derive fl6 from the tunnel key,
980 	 * for native mode, call prepare_ip6gre_xmit_{ipv4,ipv6}.
981 	 */
982 	if (t->parms.collect_md) {
983 		const struct ip_tunnel_key *key;
984 		struct erspan_metadata *md;
985 		__be32 tun_id;
986 
987 		tun_info = skb_tunnel_info_txcheck(skb);
988 		if (IS_ERR(tun_info) ||
989 		    unlikely(ip_tunnel_info_af(tun_info) != AF_INET6))
990 			goto tx_err;
991 
992 		key = &tun_info->key;
993 		memset(&fl6, 0, sizeof(fl6));
994 		fl6.flowi6_proto = IPPROTO_GRE;
995 		fl6.daddr = key->u.ipv6.dst;
996 		fl6.flowlabel = key->label;
997 		fl6.flowi6_uid = sock_net_uid(dev_net(dev), NULL);
998 		fl6.fl6_gre_key = tunnel_id_to_key32(key->tun_id);
999 
1000 		dsfield = key->tos;
1001 		if (!(tun_info->key.tun_flags & TUNNEL_ERSPAN_OPT))
1002 			goto tx_err;
1003 		if (tun_info->options_len < sizeof(*md))
1004 			goto tx_err;
1005 		md = ip_tunnel_info_opts(tun_info);
1006 
1007 		tun_id = tunnel_id_to_key32(key->tun_id);
1008 		if (md->version == 1) {
1009 			erspan_build_header(skb,
1010 					    ntohl(tun_id),
1011 					    ntohl(md->u.index), truncate,
1012 					    false);
1013 		} else if (md->version == 2) {
1014 			erspan_build_header_v2(skb,
1015 					       ntohl(tun_id),
1016 					       md->u.md2.dir,
1017 					       get_hwid(&md->u.md2),
1018 					       truncate, false);
1019 		} else {
1020 			goto tx_err;
1021 		}
1022 	} else {
1023 		switch (skb->protocol) {
1024 		case htons(ETH_P_IP):
1025 			memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
1026 			prepare_ip6gre_xmit_ipv4(skb, dev, &fl6,
1027 						 &dsfield, &encap_limit);
1028 			break;
1029 		case htons(ETH_P_IPV6):
1030 			if (ipv6_addr_equal(&t->parms.raddr, &ipv6_hdr(skb)->saddr))
1031 				goto tx_err;
1032 			if (prepare_ip6gre_xmit_ipv6(skb, dev, &fl6,
1033 						     &dsfield, &encap_limit))
1034 				goto tx_err;
1035 			break;
1036 		default:
1037 			memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6));
1038 			break;
1039 		}
1040 
1041 		if (t->parms.erspan_ver == 1)
1042 			erspan_build_header(skb, ntohl(t->parms.o_key),
1043 					    t->parms.index,
1044 					    truncate, false);
1045 		else if (t->parms.erspan_ver == 2)
1046 			erspan_build_header_v2(skb, ntohl(t->parms.o_key),
1047 					       t->parms.dir,
1048 					       t->parms.hwid,
1049 					       truncate, false);
1050 		else
1051 			goto tx_err;
1052 
1053 		fl6.daddr = t->parms.raddr;
1054 	}
1055 
1056 	/* Push GRE header. */
1057 	proto = (t->parms.erspan_ver == 1) ? htons(ETH_P_ERSPAN)
1058 					   : htons(ETH_P_ERSPAN2);
1059 	gre_build_header(skb, 8, TUNNEL_SEQ, proto, 0, htonl(atomic_fetch_inc(&t->o_seqno)));
1060 
1061 	/* TooBig packet may have updated dst->dev's mtu */
1062 	if (!t->parms.collect_md && dst && dst_mtu(dst) > dst->dev->mtu)
1063 		dst->ops->update_pmtu(dst, NULL, skb, dst->dev->mtu, false);
1064 
1065 	err = ip6_tnl_xmit(skb, dev, dsfield, &fl6, encap_limit, &mtu,
1066 			   NEXTHDR_GRE);
1067 	if (err != 0) {
1068 		/* XXX: send ICMP error even if DF is not set. */
1069 		if (err == -EMSGSIZE) {
1070 			if (skb->protocol == htons(ETH_P_IP))
1071 				icmp_ndo_send(skb, ICMP_DEST_UNREACH,
1072 					      ICMP_FRAG_NEEDED, htonl(mtu));
1073 			else
1074 				icmpv6_ndo_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
1075 		}
1076 
1077 		goto tx_err;
1078 	}
1079 	return NETDEV_TX_OK;
1080 
1081 tx_err:
1082 	stats = &t->dev->stats;
1083 	if (!IS_ERR(tun_info))
1084 		stats->tx_errors++;
1085 	stats->tx_dropped++;
1086 	kfree_skb(skb);
1087 	return NETDEV_TX_OK;
1088 }
1089 
1090 static void ip6gre_tnl_link_config_common(struct ip6_tnl *t)
1091 {
1092 	struct net_device *dev = t->dev;
1093 	struct __ip6_tnl_parm *p = &t->parms;
1094 	struct flowi6 *fl6 = &t->fl.u.ip6;
1095 
1096 	if (dev->type != ARPHRD_ETHER) {
1097 		__dev_addr_set(dev, &p->laddr, sizeof(struct in6_addr));
1098 		memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr));
1099 	}
1100 
1101 	/* Set up flowi template */
1102 	fl6->saddr = p->laddr;
1103 	fl6->daddr = p->raddr;
1104 	fl6->flowi6_oif = p->link;
1105 	fl6->flowlabel = 0;
1106 	fl6->flowi6_proto = IPPROTO_GRE;
1107 	fl6->fl6_gre_key = t->parms.o_key;
1108 
1109 	if (!(p->flags&IP6_TNL_F_USE_ORIG_TCLASS))
1110 		fl6->flowlabel |= IPV6_TCLASS_MASK & p->flowinfo;
1111 	if (!(p->flags&IP6_TNL_F_USE_ORIG_FLOWLABEL))
1112 		fl6->flowlabel |= IPV6_FLOWLABEL_MASK & p->flowinfo;
1113 
1114 	p->flags &= ~(IP6_TNL_F_CAP_XMIT|IP6_TNL_F_CAP_RCV|IP6_TNL_F_CAP_PER_PACKET);
1115 	p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr);
1116 
1117 	if (p->flags&IP6_TNL_F_CAP_XMIT &&
1118 			p->flags&IP6_TNL_F_CAP_RCV && dev->type != ARPHRD_ETHER)
1119 		dev->flags |= IFF_POINTOPOINT;
1120 	else
1121 		dev->flags &= ~IFF_POINTOPOINT;
1122 }
1123 
1124 static void ip6gre_tnl_link_config_route(struct ip6_tnl *t, int set_mtu,
1125 					 int t_hlen)
1126 {
1127 	const struct __ip6_tnl_parm *p = &t->parms;
1128 	struct net_device *dev = t->dev;
1129 
1130 	if (p->flags & IP6_TNL_F_CAP_XMIT) {
1131 		int strict = (ipv6_addr_type(&p->raddr) &
1132 			      (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL));
1133 
1134 		struct rt6_info *rt = rt6_lookup(t->net,
1135 						 &p->raddr, &p->laddr,
1136 						 p->link, NULL, strict);
1137 
1138 		if (!rt)
1139 			return;
1140 
1141 		if (rt->dst.dev) {
1142 			unsigned short dst_len = rt->dst.dev->hard_header_len +
1143 						 t_hlen;
1144 
1145 			if (t->dev->header_ops)
1146 				dev->hard_header_len = dst_len;
1147 			else
1148 				dev->needed_headroom = dst_len;
1149 
1150 			if (set_mtu) {
1151 				dev->mtu = rt->dst.dev->mtu - t_hlen;
1152 				if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1153 					dev->mtu -= 8;
1154 				if (dev->type == ARPHRD_ETHER)
1155 					dev->mtu -= ETH_HLEN;
1156 
1157 				if (dev->mtu < IPV6_MIN_MTU)
1158 					dev->mtu = IPV6_MIN_MTU;
1159 			}
1160 		}
1161 		ip6_rt_put(rt);
1162 	}
1163 }
1164 
1165 static int ip6gre_calc_hlen(struct ip6_tnl *tunnel)
1166 {
1167 	int t_hlen;
1168 
1169 	tunnel->tun_hlen = gre_calc_hlen(tunnel->parms.o_flags);
1170 	tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen;
1171 
1172 	t_hlen = tunnel->hlen + sizeof(struct ipv6hdr);
1173 
1174 	if (tunnel->dev->header_ops)
1175 		tunnel->dev->hard_header_len = LL_MAX_HEADER + t_hlen;
1176 	else
1177 		tunnel->dev->needed_headroom = LL_MAX_HEADER + t_hlen;
1178 
1179 	return t_hlen;
1180 }
1181 
1182 static void ip6gre_tnl_link_config(struct ip6_tnl *t, int set_mtu)
1183 {
1184 	ip6gre_tnl_link_config_common(t);
1185 	ip6gre_tnl_link_config_route(t, set_mtu, ip6gre_calc_hlen(t));
1186 }
1187 
1188 static void ip6gre_tnl_copy_tnl_parm(struct ip6_tnl *t,
1189 				     const struct __ip6_tnl_parm *p)
1190 {
1191 	t->parms.laddr = p->laddr;
1192 	t->parms.raddr = p->raddr;
1193 	t->parms.flags = p->flags;
1194 	t->parms.hop_limit = p->hop_limit;
1195 	t->parms.encap_limit = p->encap_limit;
1196 	t->parms.flowinfo = p->flowinfo;
1197 	t->parms.link = p->link;
1198 	t->parms.proto = p->proto;
1199 	t->parms.i_key = p->i_key;
1200 	t->parms.o_key = p->o_key;
1201 	t->parms.i_flags = p->i_flags;
1202 	t->parms.o_flags = p->o_flags;
1203 	t->parms.fwmark = p->fwmark;
1204 	t->parms.erspan_ver = p->erspan_ver;
1205 	t->parms.index = p->index;
1206 	t->parms.dir = p->dir;
1207 	t->parms.hwid = p->hwid;
1208 	dst_cache_reset(&t->dst_cache);
1209 }
1210 
1211 static int ip6gre_tnl_change(struct ip6_tnl *t, const struct __ip6_tnl_parm *p,
1212 			     int set_mtu)
1213 {
1214 	ip6gre_tnl_copy_tnl_parm(t, p);
1215 	ip6gre_tnl_link_config(t, set_mtu);
1216 	return 0;
1217 }
1218 
1219 static void ip6gre_tnl_parm_from_user(struct __ip6_tnl_parm *p,
1220 	const struct ip6_tnl_parm2 *u)
1221 {
1222 	p->laddr = u->laddr;
1223 	p->raddr = u->raddr;
1224 	p->flags = u->flags;
1225 	p->hop_limit = u->hop_limit;
1226 	p->encap_limit = u->encap_limit;
1227 	p->flowinfo = u->flowinfo;
1228 	p->link = u->link;
1229 	p->i_key = u->i_key;
1230 	p->o_key = u->o_key;
1231 	p->i_flags = gre_flags_to_tnl_flags(u->i_flags);
1232 	p->o_flags = gre_flags_to_tnl_flags(u->o_flags);
1233 	memcpy(p->name, u->name, sizeof(u->name));
1234 }
1235 
1236 static void ip6gre_tnl_parm_to_user(struct ip6_tnl_parm2 *u,
1237 	const struct __ip6_tnl_parm *p)
1238 {
1239 	u->proto = IPPROTO_GRE;
1240 	u->laddr = p->laddr;
1241 	u->raddr = p->raddr;
1242 	u->flags = p->flags;
1243 	u->hop_limit = p->hop_limit;
1244 	u->encap_limit = p->encap_limit;
1245 	u->flowinfo = p->flowinfo;
1246 	u->link = p->link;
1247 	u->i_key = p->i_key;
1248 	u->o_key = p->o_key;
1249 	u->i_flags = gre_tnl_flags_to_gre_flags(p->i_flags);
1250 	u->o_flags = gre_tnl_flags_to_gre_flags(p->o_flags);
1251 	memcpy(u->name, p->name, sizeof(u->name));
1252 }
1253 
1254 static int ip6gre_tunnel_siocdevprivate(struct net_device *dev,
1255 					struct ifreq *ifr, void __user *data,
1256 					int cmd)
1257 {
1258 	int err = 0;
1259 	struct ip6_tnl_parm2 p;
1260 	struct __ip6_tnl_parm p1;
1261 	struct ip6_tnl *t = netdev_priv(dev);
1262 	struct net *net = t->net;
1263 	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
1264 
1265 	memset(&p1, 0, sizeof(p1));
1266 
1267 	switch (cmd) {
1268 	case SIOCGETTUNNEL:
1269 		if (dev == ign->fb_tunnel_dev) {
1270 			if (copy_from_user(&p, data, sizeof(p))) {
1271 				err = -EFAULT;
1272 				break;
1273 			}
1274 			ip6gre_tnl_parm_from_user(&p1, &p);
1275 			t = ip6gre_tunnel_locate(net, &p1, 0);
1276 			if (!t)
1277 				t = netdev_priv(dev);
1278 		}
1279 		memset(&p, 0, sizeof(p));
1280 		ip6gre_tnl_parm_to_user(&p, &t->parms);
1281 		if (copy_to_user(data, &p, sizeof(p)))
1282 			err = -EFAULT;
1283 		break;
1284 
1285 	case SIOCADDTUNNEL:
1286 	case SIOCCHGTUNNEL:
1287 		err = -EPERM;
1288 		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1289 			goto done;
1290 
1291 		err = -EFAULT;
1292 		if (copy_from_user(&p, data, sizeof(p)))
1293 			goto done;
1294 
1295 		err = -EINVAL;
1296 		if ((p.i_flags|p.o_flags)&(GRE_VERSION|GRE_ROUTING))
1297 			goto done;
1298 
1299 		if (!(p.i_flags&GRE_KEY))
1300 			p.i_key = 0;
1301 		if (!(p.o_flags&GRE_KEY))
1302 			p.o_key = 0;
1303 
1304 		ip6gre_tnl_parm_from_user(&p1, &p);
1305 		t = ip6gre_tunnel_locate(net, &p1, cmd == SIOCADDTUNNEL);
1306 
1307 		if (dev != ign->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) {
1308 			if (t) {
1309 				if (t->dev != dev) {
1310 					err = -EEXIST;
1311 					break;
1312 				}
1313 			} else {
1314 				t = netdev_priv(dev);
1315 
1316 				ip6gre_tunnel_unlink(ign, t);
1317 				synchronize_net();
1318 				ip6gre_tnl_change(t, &p1, 1);
1319 				ip6gre_tunnel_link(ign, t);
1320 				netdev_state_change(dev);
1321 			}
1322 		}
1323 
1324 		if (t) {
1325 			err = 0;
1326 
1327 			memset(&p, 0, sizeof(p));
1328 			ip6gre_tnl_parm_to_user(&p, &t->parms);
1329 			if (copy_to_user(data, &p, sizeof(p)))
1330 				err = -EFAULT;
1331 		} else
1332 			err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
1333 		break;
1334 
1335 	case SIOCDELTUNNEL:
1336 		err = -EPERM;
1337 		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1338 			goto done;
1339 
1340 		if (dev == ign->fb_tunnel_dev) {
1341 			err = -EFAULT;
1342 			if (copy_from_user(&p, data, sizeof(p)))
1343 				goto done;
1344 			err = -ENOENT;
1345 			ip6gre_tnl_parm_from_user(&p1, &p);
1346 			t = ip6gre_tunnel_locate(net, &p1, 0);
1347 			if (!t)
1348 				goto done;
1349 			err = -EPERM;
1350 			if (t == netdev_priv(ign->fb_tunnel_dev))
1351 				goto done;
1352 			dev = t->dev;
1353 		}
1354 		unregister_netdevice(dev);
1355 		err = 0;
1356 		break;
1357 
1358 	default:
1359 		err = -EINVAL;
1360 	}
1361 
1362 done:
1363 	return err;
1364 }
1365 
1366 static int ip6gre_header(struct sk_buff *skb, struct net_device *dev,
1367 			 unsigned short type, const void *daddr,
1368 			 const void *saddr, unsigned int len)
1369 {
1370 	struct ip6_tnl *t = netdev_priv(dev);
1371 	struct ipv6hdr *ipv6h;
1372 	__be16 *p;
1373 
1374 	ipv6h = skb_push(skb, t->hlen + sizeof(*ipv6h));
1375 	ip6_flow_hdr(ipv6h, 0, ip6_make_flowlabel(dev_net(dev), skb,
1376 						  t->fl.u.ip6.flowlabel,
1377 						  true, &t->fl.u.ip6));
1378 	ipv6h->hop_limit = t->parms.hop_limit;
1379 	ipv6h->nexthdr = NEXTHDR_GRE;
1380 	ipv6h->saddr = t->parms.laddr;
1381 	ipv6h->daddr = t->parms.raddr;
1382 
1383 	p = (__be16 *)(ipv6h + 1);
1384 	p[0] = t->parms.o_flags;
1385 	p[1] = htons(type);
1386 
1387 	/*
1388 	 *	Set the source hardware address.
1389 	 */
1390 
1391 	if (saddr)
1392 		memcpy(&ipv6h->saddr, saddr, sizeof(struct in6_addr));
1393 	if (daddr)
1394 		memcpy(&ipv6h->daddr, daddr, sizeof(struct in6_addr));
1395 	if (!ipv6_addr_any(&ipv6h->daddr))
1396 		return t->hlen;
1397 
1398 	return -t->hlen;
1399 }
1400 
1401 static const struct header_ops ip6gre_header_ops = {
1402 	.create	= ip6gre_header,
1403 };
1404 
1405 static const struct net_device_ops ip6gre_netdev_ops = {
1406 	.ndo_init		= ip6gre_tunnel_init,
1407 	.ndo_uninit		= ip6gre_tunnel_uninit,
1408 	.ndo_start_xmit		= ip6gre_tunnel_xmit,
1409 	.ndo_siocdevprivate	= ip6gre_tunnel_siocdevprivate,
1410 	.ndo_change_mtu		= ip6_tnl_change_mtu,
1411 	.ndo_get_stats64	= dev_get_tstats64,
1412 	.ndo_get_iflink		= ip6_tnl_get_iflink,
1413 };
1414 
1415 static void ip6gre_dev_free(struct net_device *dev)
1416 {
1417 	struct ip6_tnl *t = netdev_priv(dev);
1418 
1419 	gro_cells_destroy(&t->gro_cells);
1420 	dst_cache_destroy(&t->dst_cache);
1421 	free_percpu(dev->tstats);
1422 }
1423 
1424 static void ip6gre_tunnel_setup(struct net_device *dev)
1425 {
1426 	dev->netdev_ops = &ip6gre_netdev_ops;
1427 	dev->needs_free_netdev = true;
1428 	dev->priv_destructor = ip6gre_dev_free;
1429 
1430 	dev->type = ARPHRD_IP6GRE;
1431 
1432 	dev->flags |= IFF_NOARP;
1433 	dev->addr_len = sizeof(struct in6_addr);
1434 	netif_keep_dst(dev);
1435 	/* This perm addr will be used as interface identifier by IPv6 */
1436 	dev->addr_assign_type = NET_ADDR_RANDOM;
1437 	eth_random_addr(dev->perm_addr);
1438 }
1439 
1440 #define GRE6_FEATURES (NETIF_F_SG |		\
1441 		       NETIF_F_FRAGLIST |	\
1442 		       NETIF_F_HIGHDMA |	\
1443 		       NETIF_F_HW_CSUM)
1444 
1445 static void ip6gre_tnl_init_features(struct net_device *dev)
1446 {
1447 	struct ip6_tnl *nt = netdev_priv(dev);
1448 	__be16 flags;
1449 
1450 	dev->features		|= GRE6_FEATURES | NETIF_F_LLTX;
1451 	dev->hw_features	|= GRE6_FEATURES;
1452 
1453 	flags = nt->parms.o_flags;
1454 
1455 	/* TCP offload with GRE SEQ is not supported, nor can we support 2
1456 	 * levels of outer headers requiring an update.
1457 	 */
1458 	if (flags & TUNNEL_SEQ)
1459 		return;
1460 	if (flags & TUNNEL_CSUM && nt->encap.type != TUNNEL_ENCAP_NONE)
1461 		return;
1462 
1463 	dev->features |= NETIF_F_GSO_SOFTWARE;
1464 	dev->hw_features |= NETIF_F_GSO_SOFTWARE;
1465 }
1466 
1467 static int ip6gre_tunnel_init_common(struct net_device *dev)
1468 {
1469 	struct ip6_tnl *tunnel;
1470 	int ret;
1471 	int t_hlen;
1472 
1473 	tunnel = netdev_priv(dev);
1474 
1475 	tunnel->dev = dev;
1476 	tunnel->net = dev_net(dev);
1477 	strcpy(tunnel->parms.name, dev->name);
1478 
1479 	dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
1480 	if (!dev->tstats)
1481 		return -ENOMEM;
1482 
1483 	ret = dst_cache_init(&tunnel->dst_cache, GFP_KERNEL);
1484 	if (ret)
1485 		goto cleanup_alloc_pcpu_stats;
1486 
1487 	ret = gro_cells_init(&tunnel->gro_cells, dev);
1488 	if (ret)
1489 		goto cleanup_dst_cache_init;
1490 
1491 	t_hlen = ip6gre_calc_hlen(tunnel);
1492 	dev->mtu = ETH_DATA_LEN - t_hlen;
1493 	if (dev->type == ARPHRD_ETHER)
1494 		dev->mtu -= ETH_HLEN;
1495 	if (!(tunnel->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1496 		dev->mtu -= 8;
1497 
1498 	if (tunnel->parms.collect_md) {
1499 		netif_keep_dst(dev);
1500 	}
1501 	ip6gre_tnl_init_features(dev);
1502 
1503 	netdev_hold(dev, &tunnel->dev_tracker, GFP_KERNEL);
1504 	return 0;
1505 
1506 cleanup_dst_cache_init:
1507 	dst_cache_destroy(&tunnel->dst_cache);
1508 cleanup_alloc_pcpu_stats:
1509 	free_percpu(dev->tstats);
1510 	dev->tstats = NULL;
1511 	return ret;
1512 }
1513 
1514 static int ip6gre_tunnel_init(struct net_device *dev)
1515 {
1516 	struct ip6_tnl *tunnel;
1517 	int ret;
1518 
1519 	ret = ip6gre_tunnel_init_common(dev);
1520 	if (ret)
1521 		return ret;
1522 
1523 	tunnel = netdev_priv(dev);
1524 
1525 	if (tunnel->parms.collect_md)
1526 		return 0;
1527 
1528 	__dev_addr_set(dev, &tunnel->parms.laddr, sizeof(struct in6_addr));
1529 	memcpy(dev->broadcast, &tunnel->parms.raddr, sizeof(struct in6_addr));
1530 
1531 	if (ipv6_addr_any(&tunnel->parms.raddr))
1532 		dev->header_ops = &ip6gre_header_ops;
1533 
1534 	return 0;
1535 }
1536 
1537 static void ip6gre_fb_tunnel_init(struct net_device *dev)
1538 {
1539 	struct ip6_tnl *tunnel = netdev_priv(dev);
1540 
1541 	tunnel->dev = dev;
1542 	tunnel->net = dev_net(dev);
1543 	strcpy(tunnel->parms.name, dev->name);
1544 
1545 	tunnel->hlen		= sizeof(struct ipv6hdr) + 4;
1546 }
1547 
1548 static struct inet6_protocol ip6gre_protocol __read_mostly = {
1549 	.handler     = gre_rcv,
1550 	.err_handler = ip6gre_err,
1551 	.flags       = INET6_PROTO_FINAL,
1552 };
1553 
1554 static void ip6gre_destroy_tunnels(struct net *net, struct list_head *head)
1555 {
1556 	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
1557 	struct net_device *dev, *aux;
1558 	int prio;
1559 
1560 	for_each_netdev_safe(net, dev, aux)
1561 		if (dev->rtnl_link_ops == &ip6gre_link_ops ||
1562 		    dev->rtnl_link_ops == &ip6gre_tap_ops ||
1563 		    dev->rtnl_link_ops == &ip6erspan_tap_ops)
1564 			unregister_netdevice_queue(dev, head);
1565 
1566 	for (prio = 0; prio < 4; prio++) {
1567 		int h;
1568 		for (h = 0; h < IP6_GRE_HASH_SIZE; h++) {
1569 			struct ip6_tnl *t;
1570 
1571 			t = rtnl_dereference(ign->tunnels[prio][h]);
1572 
1573 			while (t) {
1574 				/* If dev is in the same netns, it has already
1575 				 * been added to the list by the previous loop.
1576 				 */
1577 				if (!net_eq(dev_net(t->dev), net))
1578 					unregister_netdevice_queue(t->dev,
1579 								   head);
1580 				t = rtnl_dereference(t->next);
1581 			}
1582 		}
1583 	}
1584 }
1585 
1586 static int __net_init ip6gre_init_net(struct net *net)
1587 {
1588 	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
1589 	struct net_device *ndev;
1590 	int err;
1591 
1592 	if (!net_has_fallback_tunnels(net))
1593 		return 0;
1594 	ndev = alloc_netdev(sizeof(struct ip6_tnl), "ip6gre0",
1595 			    NET_NAME_UNKNOWN, ip6gre_tunnel_setup);
1596 	if (!ndev) {
1597 		err = -ENOMEM;
1598 		goto err_alloc_dev;
1599 	}
1600 	ign->fb_tunnel_dev = ndev;
1601 	dev_net_set(ign->fb_tunnel_dev, net);
1602 	/* FB netdevice is special: we have one, and only one per netns.
1603 	 * Allowing to move it to another netns is clearly unsafe.
1604 	 */
1605 	ign->fb_tunnel_dev->features |= NETIF_F_NETNS_LOCAL;
1606 
1607 
1608 	ip6gre_fb_tunnel_init(ign->fb_tunnel_dev);
1609 	ign->fb_tunnel_dev->rtnl_link_ops = &ip6gre_link_ops;
1610 
1611 	err = register_netdev(ign->fb_tunnel_dev);
1612 	if (err)
1613 		goto err_reg_dev;
1614 
1615 	rcu_assign_pointer(ign->tunnels_wc[0],
1616 			   netdev_priv(ign->fb_tunnel_dev));
1617 	return 0;
1618 
1619 err_reg_dev:
1620 	free_netdev(ndev);
1621 err_alloc_dev:
1622 	return err;
1623 }
1624 
1625 static void __net_exit ip6gre_exit_batch_net(struct list_head *net_list)
1626 {
1627 	struct net *net;
1628 	LIST_HEAD(list);
1629 
1630 	rtnl_lock();
1631 	list_for_each_entry(net, net_list, exit_list)
1632 		ip6gre_destroy_tunnels(net, &list);
1633 	unregister_netdevice_many(&list);
1634 	rtnl_unlock();
1635 }
1636 
1637 static struct pernet_operations ip6gre_net_ops = {
1638 	.init = ip6gre_init_net,
1639 	.exit_batch = ip6gre_exit_batch_net,
1640 	.id   = &ip6gre_net_id,
1641 	.size = sizeof(struct ip6gre_net),
1642 };
1643 
1644 static int ip6gre_tunnel_validate(struct nlattr *tb[], struct nlattr *data[],
1645 				  struct netlink_ext_ack *extack)
1646 {
1647 	__be16 flags;
1648 
1649 	if (!data)
1650 		return 0;
1651 
1652 	flags = 0;
1653 	if (data[IFLA_GRE_IFLAGS])
1654 		flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]);
1655 	if (data[IFLA_GRE_OFLAGS])
1656 		flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]);
1657 	if (flags & (GRE_VERSION|GRE_ROUTING))
1658 		return -EINVAL;
1659 
1660 	return 0;
1661 }
1662 
1663 static int ip6gre_tap_validate(struct nlattr *tb[], struct nlattr *data[],
1664 			       struct netlink_ext_ack *extack)
1665 {
1666 	struct in6_addr daddr;
1667 
1668 	if (tb[IFLA_ADDRESS]) {
1669 		if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
1670 			return -EINVAL;
1671 		if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
1672 			return -EADDRNOTAVAIL;
1673 	}
1674 
1675 	if (!data)
1676 		goto out;
1677 
1678 	if (data[IFLA_GRE_REMOTE]) {
1679 		daddr = nla_get_in6_addr(data[IFLA_GRE_REMOTE]);
1680 		if (ipv6_addr_any(&daddr))
1681 			return -EINVAL;
1682 	}
1683 
1684 out:
1685 	return ip6gre_tunnel_validate(tb, data, extack);
1686 }
1687 
1688 static int ip6erspan_tap_validate(struct nlattr *tb[], struct nlattr *data[],
1689 				  struct netlink_ext_ack *extack)
1690 {
1691 	__be16 flags = 0;
1692 	int ret, ver = 0;
1693 
1694 	if (!data)
1695 		return 0;
1696 
1697 	ret = ip6gre_tap_validate(tb, data, extack);
1698 	if (ret)
1699 		return ret;
1700 
1701 	/* ERSPAN should only have GRE sequence and key flag */
1702 	if (data[IFLA_GRE_OFLAGS])
1703 		flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]);
1704 	if (data[IFLA_GRE_IFLAGS])
1705 		flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]);
1706 	if (!data[IFLA_GRE_COLLECT_METADATA] &&
1707 	    flags != (GRE_SEQ | GRE_KEY))
1708 		return -EINVAL;
1709 
1710 	/* ERSPAN Session ID only has 10-bit. Since we reuse
1711 	 * 32-bit key field as ID, check it's range.
1712 	 */
1713 	if (data[IFLA_GRE_IKEY] &&
1714 	    (ntohl(nla_get_be32(data[IFLA_GRE_IKEY])) & ~ID_MASK))
1715 		return -EINVAL;
1716 
1717 	if (data[IFLA_GRE_OKEY] &&
1718 	    (ntohl(nla_get_be32(data[IFLA_GRE_OKEY])) & ~ID_MASK))
1719 		return -EINVAL;
1720 
1721 	if (data[IFLA_GRE_ERSPAN_VER]) {
1722 		ver = nla_get_u8(data[IFLA_GRE_ERSPAN_VER]);
1723 		if (ver != 1 && ver != 2)
1724 			return -EINVAL;
1725 	}
1726 
1727 	if (ver == 1) {
1728 		if (data[IFLA_GRE_ERSPAN_INDEX]) {
1729 			u32 index = nla_get_u32(data[IFLA_GRE_ERSPAN_INDEX]);
1730 
1731 			if (index & ~INDEX_MASK)
1732 				return -EINVAL;
1733 		}
1734 	} else if (ver == 2) {
1735 		if (data[IFLA_GRE_ERSPAN_DIR]) {
1736 			u16 dir = nla_get_u8(data[IFLA_GRE_ERSPAN_DIR]);
1737 
1738 			if (dir & ~(DIR_MASK >> DIR_OFFSET))
1739 				return -EINVAL;
1740 		}
1741 
1742 		if (data[IFLA_GRE_ERSPAN_HWID]) {
1743 			u16 hwid = nla_get_u16(data[IFLA_GRE_ERSPAN_HWID]);
1744 
1745 			if (hwid & ~(HWID_MASK >> HWID_OFFSET))
1746 				return -EINVAL;
1747 		}
1748 	}
1749 
1750 	return 0;
1751 }
1752 
1753 static void ip6erspan_set_version(struct nlattr *data[],
1754 				  struct __ip6_tnl_parm *parms)
1755 {
1756 	if (!data)
1757 		return;
1758 
1759 	parms->erspan_ver = 1;
1760 	if (data[IFLA_GRE_ERSPAN_VER])
1761 		parms->erspan_ver = nla_get_u8(data[IFLA_GRE_ERSPAN_VER]);
1762 
1763 	if (parms->erspan_ver == 1) {
1764 		if (data[IFLA_GRE_ERSPAN_INDEX])
1765 			parms->index = nla_get_u32(data[IFLA_GRE_ERSPAN_INDEX]);
1766 	} else if (parms->erspan_ver == 2) {
1767 		if (data[IFLA_GRE_ERSPAN_DIR])
1768 			parms->dir = nla_get_u8(data[IFLA_GRE_ERSPAN_DIR]);
1769 		if (data[IFLA_GRE_ERSPAN_HWID])
1770 			parms->hwid = nla_get_u16(data[IFLA_GRE_ERSPAN_HWID]);
1771 	}
1772 }
1773 
1774 static void ip6gre_netlink_parms(struct nlattr *data[],
1775 				struct __ip6_tnl_parm *parms)
1776 {
1777 	memset(parms, 0, sizeof(*parms));
1778 
1779 	if (!data)
1780 		return;
1781 
1782 	if (data[IFLA_GRE_LINK])
1783 		parms->link = nla_get_u32(data[IFLA_GRE_LINK]);
1784 
1785 	if (data[IFLA_GRE_IFLAGS])
1786 		parms->i_flags = gre_flags_to_tnl_flags(
1787 				nla_get_be16(data[IFLA_GRE_IFLAGS]));
1788 
1789 	if (data[IFLA_GRE_OFLAGS])
1790 		parms->o_flags = gre_flags_to_tnl_flags(
1791 				nla_get_be16(data[IFLA_GRE_OFLAGS]));
1792 
1793 	if (data[IFLA_GRE_IKEY])
1794 		parms->i_key = nla_get_be32(data[IFLA_GRE_IKEY]);
1795 
1796 	if (data[IFLA_GRE_OKEY])
1797 		parms->o_key = nla_get_be32(data[IFLA_GRE_OKEY]);
1798 
1799 	if (data[IFLA_GRE_LOCAL])
1800 		parms->laddr = nla_get_in6_addr(data[IFLA_GRE_LOCAL]);
1801 
1802 	if (data[IFLA_GRE_REMOTE])
1803 		parms->raddr = nla_get_in6_addr(data[IFLA_GRE_REMOTE]);
1804 
1805 	if (data[IFLA_GRE_TTL])
1806 		parms->hop_limit = nla_get_u8(data[IFLA_GRE_TTL]);
1807 
1808 	if (data[IFLA_GRE_ENCAP_LIMIT])
1809 		parms->encap_limit = nla_get_u8(data[IFLA_GRE_ENCAP_LIMIT]);
1810 
1811 	if (data[IFLA_GRE_FLOWINFO])
1812 		parms->flowinfo = nla_get_be32(data[IFLA_GRE_FLOWINFO]);
1813 
1814 	if (data[IFLA_GRE_FLAGS])
1815 		parms->flags = nla_get_u32(data[IFLA_GRE_FLAGS]);
1816 
1817 	if (data[IFLA_GRE_FWMARK])
1818 		parms->fwmark = nla_get_u32(data[IFLA_GRE_FWMARK]);
1819 
1820 	if (data[IFLA_GRE_COLLECT_METADATA])
1821 		parms->collect_md = true;
1822 }
1823 
1824 static int ip6gre_tap_init(struct net_device *dev)
1825 {
1826 	int ret;
1827 
1828 	ret = ip6gre_tunnel_init_common(dev);
1829 	if (ret)
1830 		return ret;
1831 
1832 	dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1833 
1834 	return 0;
1835 }
1836 
1837 static const struct net_device_ops ip6gre_tap_netdev_ops = {
1838 	.ndo_init = ip6gre_tap_init,
1839 	.ndo_uninit = ip6gre_tunnel_uninit,
1840 	.ndo_start_xmit = ip6gre_tunnel_xmit,
1841 	.ndo_set_mac_address = eth_mac_addr,
1842 	.ndo_validate_addr = eth_validate_addr,
1843 	.ndo_change_mtu = ip6_tnl_change_mtu,
1844 	.ndo_get_stats64 = dev_get_tstats64,
1845 	.ndo_get_iflink = ip6_tnl_get_iflink,
1846 };
1847 
1848 static int ip6erspan_calc_hlen(struct ip6_tnl *tunnel)
1849 {
1850 	int t_hlen;
1851 
1852 	tunnel->tun_hlen = 8;
1853 	tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen +
1854 		       erspan_hdr_len(tunnel->parms.erspan_ver);
1855 
1856 	t_hlen = tunnel->hlen + sizeof(struct ipv6hdr);
1857 	tunnel->dev->needed_headroom = LL_MAX_HEADER + t_hlen;
1858 	return t_hlen;
1859 }
1860 
1861 static int ip6erspan_tap_init(struct net_device *dev)
1862 {
1863 	struct ip6_tnl *tunnel;
1864 	int t_hlen;
1865 	int ret;
1866 
1867 	tunnel = netdev_priv(dev);
1868 
1869 	tunnel->dev = dev;
1870 	tunnel->net = dev_net(dev);
1871 	strcpy(tunnel->parms.name, dev->name);
1872 
1873 	dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
1874 	if (!dev->tstats)
1875 		return -ENOMEM;
1876 
1877 	ret = dst_cache_init(&tunnel->dst_cache, GFP_KERNEL);
1878 	if (ret)
1879 		goto cleanup_alloc_pcpu_stats;
1880 
1881 	ret = gro_cells_init(&tunnel->gro_cells, dev);
1882 	if (ret)
1883 		goto cleanup_dst_cache_init;
1884 
1885 	t_hlen = ip6erspan_calc_hlen(tunnel);
1886 	dev->mtu = ETH_DATA_LEN - t_hlen;
1887 	if (dev->type == ARPHRD_ETHER)
1888 		dev->mtu -= ETH_HLEN;
1889 	if (!(tunnel->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1890 		dev->mtu -= 8;
1891 
1892 	dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1893 	ip6erspan_tnl_link_config(tunnel, 1);
1894 
1895 	netdev_hold(dev, &tunnel->dev_tracker, GFP_KERNEL);
1896 	return 0;
1897 
1898 cleanup_dst_cache_init:
1899 	dst_cache_destroy(&tunnel->dst_cache);
1900 cleanup_alloc_pcpu_stats:
1901 	free_percpu(dev->tstats);
1902 	dev->tstats = NULL;
1903 	return ret;
1904 }
1905 
1906 static const struct net_device_ops ip6erspan_netdev_ops = {
1907 	.ndo_init =		ip6erspan_tap_init,
1908 	.ndo_uninit =		ip6erspan_tunnel_uninit,
1909 	.ndo_start_xmit =	ip6erspan_tunnel_xmit,
1910 	.ndo_set_mac_address =	eth_mac_addr,
1911 	.ndo_validate_addr =	eth_validate_addr,
1912 	.ndo_change_mtu =	ip6_tnl_change_mtu,
1913 	.ndo_get_stats64 =	dev_get_tstats64,
1914 	.ndo_get_iflink =	ip6_tnl_get_iflink,
1915 };
1916 
1917 static void ip6gre_tap_setup(struct net_device *dev)
1918 {
1919 
1920 	ether_setup(dev);
1921 
1922 	dev->max_mtu = 0;
1923 	dev->netdev_ops = &ip6gre_tap_netdev_ops;
1924 	dev->needs_free_netdev = true;
1925 	dev->priv_destructor = ip6gre_dev_free;
1926 
1927 	dev->priv_flags &= ~IFF_TX_SKB_SHARING;
1928 	dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1929 	netif_keep_dst(dev);
1930 }
1931 
1932 static bool ip6gre_netlink_encap_parms(struct nlattr *data[],
1933 				       struct ip_tunnel_encap *ipencap)
1934 {
1935 	bool ret = false;
1936 
1937 	memset(ipencap, 0, sizeof(*ipencap));
1938 
1939 	if (!data)
1940 		return ret;
1941 
1942 	if (data[IFLA_GRE_ENCAP_TYPE]) {
1943 		ret = true;
1944 		ipencap->type = nla_get_u16(data[IFLA_GRE_ENCAP_TYPE]);
1945 	}
1946 
1947 	if (data[IFLA_GRE_ENCAP_FLAGS]) {
1948 		ret = true;
1949 		ipencap->flags = nla_get_u16(data[IFLA_GRE_ENCAP_FLAGS]);
1950 	}
1951 
1952 	if (data[IFLA_GRE_ENCAP_SPORT]) {
1953 		ret = true;
1954 		ipencap->sport = nla_get_be16(data[IFLA_GRE_ENCAP_SPORT]);
1955 	}
1956 
1957 	if (data[IFLA_GRE_ENCAP_DPORT]) {
1958 		ret = true;
1959 		ipencap->dport = nla_get_be16(data[IFLA_GRE_ENCAP_DPORT]);
1960 	}
1961 
1962 	return ret;
1963 }
1964 
1965 static int ip6gre_newlink_common(struct net *src_net, struct net_device *dev,
1966 				 struct nlattr *tb[], struct nlattr *data[],
1967 				 struct netlink_ext_ack *extack)
1968 {
1969 	struct ip6_tnl *nt;
1970 	struct ip_tunnel_encap ipencap;
1971 	int err;
1972 
1973 	nt = netdev_priv(dev);
1974 
1975 	if (ip6gre_netlink_encap_parms(data, &ipencap)) {
1976 		int err = ip6_tnl_encap_setup(nt, &ipencap);
1977 
1978 		if (err < 0)
1979 			return err;
1980 	}
1981 
1982 	if (dev->type == ARPHRD_ETHER && !tb[IFLA_ADDRESS])
1983 		eth_hw_addr_random(dev);
1984 
1985 	nt->dev = dev;
1986 	nt->net = dev_net(dev);
1987 
1988 	err = register_netdevice(dev);
1989 	if (err)
1990 		goto out;
1991 
1992 	if (tb[IFLA_MTU])
1993 		ip6_tnl_change_mtu(dev, nla_get_u32(tb[IFLA_MTU]));
1994 
1995 out:
1996 	return err;
1997 }
1998 
1999 static int ip6gre_newlink(struct net *src_net, struct net_device *dev,
2000 			  struct nlattr *tb[], struct nlattr *data[],
2001 			  struct netlink_ext_ack *extack)
2002 {
2003 	struct ip6_tnl *nt = netdev_priv(dev);
2004 	struct net *net = dev_net(dev);
2005 	struct ip6gre_net *ign;
2006 	int err;
2007 
2008 	ip6gre_netlink_parms(data, &nt->parms);
2009 	ign = net_generic(net, ip6gre_net_id);
2010 
2011 	if (nt->parms.collect_md) {
2012 		if (rtnl_dereference(ign->collect_md_tun))
2013 			return -EEXIST;
2014 	} else {
2015 		if (ip6gre_tunnel_find(net, &nt->parms, dev->type))
2016 			return -EEXIST;
2017 	}
2018 
2019 	err = ip6gre_newlink_common(src_net, dev, tb, data, extack);
2020 	if (!err) {
2021 		ip6gre_tnl_link_config(nt, !tb[IFLA_MTU]);
2022 		ip6gre_tunnel_link_md(ign, nt);
2023 		ip6gre_tunnel_link(net_generic(net, ip6gre_net_id), nt);
2024 	}
2025 	return err;
2026 }
2027 
2028 static struct ip6_tnl *
2029 ip6gre_changelink_common(struct net_device *dev, struct nlattr *tb[],
2030 			 struct nlattr *data[], struct __ip6_tnl_parm *p_p,
2031 			 struct netlink_ext_ack *extack)
2032 {
2033 	struct ip6_tnl *t, *nt = netdev_priv(dev);
2034 	struct net *net = nt->net;
2035 	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
2036 	struct ip_tunnel_encap ipencap;
2037 
2038 	if (dev == ign->fb_tunnel_dev)
2039 		return ERR_PTR(-EINVAL);
2040 
2041 	if (ip6gre_netlink_encap_parms(data, &ipencap)) {
2042 		int err = ip6_tnl_encap_setup(nt, &ipencap);
2043 
2044 		if (err < 0)
2045 			return ERR_PTR(err);
2046 	}
2047 
2048 	ip6gre_netlink_parms(data, p_p);
2049 
2050 	t = ip6gre_tunnel_locate(net, p_p, 0);
2051 
2052 	if (t) {
2053 		if (t->dev != dev)
2054 			return ERR_PTR(-EEXIST);
2055 	} else {
2056 		t = nt;
2057 	}
2058 
2059 	return t;
2060 }
2061 
2062 static int ip6gre_changelink(struct net_device *dev, struct nlattr *tb[],
2063 			     struct nlattr *data[],
2064 			     struct netlink_ext_ack *extack)
2065 {
2066 	struct ip6_tnl *t = netdev_priv(dev);
2067 	struct ip6gre_net *ign = net_generic(t->net, ip6gre_net_id);
2068 	struct __ip6_tnl_parm p;
2069 
2070 	t = ip6gre_changelink_common(dev, tb, data, &p, extack);
2071 	if (IS_ERR(t))
2072 		return PTR_ERR(t);
2073 
2074 	ip6gre_tunnel_unlink_md(ign, t);
2075 	ip6gre_tunnel_unlink(ign, t);
2076 	ip6gre_tnl_change(t, &p, !tb[IFLA_MTU]);
2077 	ip6gre_tunnel_link_md(ign, t);
2078 	ip6gre_tunnel_link(ign, t);
2079 	return 0;
2080 }
2081 
2082 static void ip6gre_dellink(struct net_device *dev, struct list_head *head)
2083 {
2084 	struct net *net = dev_net(dev);
2085 	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
2086 
2087 	if (dev != ign->fb_tunnel_dev)
2088 		unregister_netdevice_queue(dev, head);
2089 }
2090 
2091 static size_t ip6gre_get_size(const struct net_device *dev)
2092 {
2093 	return
2094 		/* IFLA_GRE_LINK */
2095 		nla_total_size(4) +
2096 		/* IFLA_GRE_IFLAGS */
2097 		nla_total_size(2) +
2098 		/* IFLA_GRE_OFLAGS */
2099 		nla_total_size(2) +
2100 		/* IFLA_GRE_IKEY */
2101 		nla_total_size(4) +
2102 		/* IFLA_GRE_OKEY */
2103 		nla_total_size(4) +
2104 		/* IFLA_GRE_LOCAL */
2105 		nla_total_size(sizeof(struct in6_addr)) +
2106 		/* IFLA_GRE_REMOTE */
2107 		nla_total_size(sizeof(struct in6_addr)) +
2108 		/* IFLA_GRE_TTL */
2109 		nla_total_size(1) +
2110 		/* IFLA_GRE_ENCAP_LIMIT */
2111 		nla_total_size(1) +
2112 		/* IFLA_GRE_FLOWINFO */
2113 		nla_total_size(4) +
2114 		/* IFLA_GRE_FLAGS */
2115 		nla_total_size(4) +
2116 		/* IFLA_GRE_ENCAP_TYPE */
2117 		nla_total_size(2) +
2118 		/* IFLA_GRE_ENCAP_FLAGS */
2119 		nla_total_size(2) +
2120 		/* IFLA_GRE_ENCAP_SPORT */
2121 		nla_total_size(2) +
2122 		/* IFLA_GRE_ENCAP_DPORT */
2123 		nla_total_size(2) +
2124 		/* IFLA_GRE_COLLECT_METADATA */
2125 		nla_total_size(0) +
2126 		/* IFLA_GRE_FWMARK */
2127 		nla_total_size(4) +
2128 		/* IFLA_GRE_ERSPAN_INDEX */
2129 		nla_total_size(4) +
2130 		0;
2131 }
2132 
2133 static int ip6gre_fill_info(struct sk_buff *skb, const struct net_device *dev)
2134 {
2135 	struct ip6_tnl *t = netdev_priv(dev);
2136 	struct __ip6_tnl_parm *p = &t->parms;
2137 	__be16 o_flags = p->o_flags;
2138 
2139 	if (p->erspan_ver == 1 || p->erspan_ver == 2) {
2140 		if (!p->collect_md)
2141 			o_flags |= TUNNEL_KEY;
2142 
2143 		if (nla_put_u8(skb, IFLA_GRE_ERSPAN_VER, p->erspan_ver))
2144 			goto nla_put_failure;
2145 
2146 		if (p->erspan_ver == 1) {
2147 			if (nla_put_u32(skb, IFLA_GRE_ERSPAN_INDEX, p->index))
2148 				goto nla_put_failure;
2149 		} else {
2150 			if (nla_put_u8(skb, IFLA_GRE_ERSPAN_DIR, p->dir))
2151 				goto nla_put_failure;
2152 			if (nla_put_u16(skb, IFLA_GRE_ERSPAN_HWID, p->hwid))
2153 				goto nla_put_failure;
2154 		}
2155 	}
2156 
2157 	if (nla_put_u32(skb, IFLA_GRE_LINK, p->link) ||
2158 	    nla_put_be16(skb, IFLA_GRE_IFLAGS,
2159 			 gre_tnl_flags_to_gre_flags(p->i_flags)) ||
2160 	    nla_put_be16(skb, IFLA_GRE_OFLAGS,
2161 			 gre_tnl_flags_to_gre_flags(o_flags)) ||
2162 	    nla_put_be32(skb, IFLA_GRE_IKEY, p->i_key) ||
2163 	    nla_put_be32(skb, IFLA_GRE_OKEY, p->o_key) ||
2164 	    nla_put_in6_addr(skb, IFLA_GRE_LOCAL, &p->laddr) ||
2165 	    nla_put_in6_addr(skb, IFLA_GRE_REMOTE, &p->raddr) ||
2166 	    nla_put_u8(skb, IFLA_GRE_TTL, p->hop_limit) ||
2167 	    nla_put_u8(skb, IFLA_GRE_ENCAP_LIMIT, p->encap_limit) ||
2168 	    nla_put_be32(skb, IFLA_GRE_FLOWINFO, p->flowinfo) ||
2169 	    nla_put_u32(skb, IFLA_GRE_FLAGS, p->flags) ||
2170 	    nla_put_u32(skb, IFLA_GRE_FWMARK, p->fwmark))
2171 		goto nla_put_failure;
2172 
2173 	if (nla_put_u16(skb, IFLA_GRE_ENCAP_TYPE,
2174 			t->encap.type) ||
2175 	    nla_put_be16(skb, IFLA_GRE_ENCAP_SPORT,
2176 			 t->encap.sport) ||
2177 	    nla_put_be16(skb, IFLA_GRE_ENCAP_DPORT,
2178 			 t->encap.dport) ||
2179 	    nla_put_u16(skb, IFLA_GRE_ENCAP_FLAGS,
2180 			t->encap.flags))
2181 		goto nla_put_failure;
2182 
2183 	if (p->collect_md) {
2184 		if (nla_put_flag(skb, IFLA_GRE_COLLECT_METADATA))
2185 			goto nla_put_failure;
2186 	}
2187 
2188 	return 0;
2189 
2190 nla_put_failure:
2191 	return -EMSGSIZE;
2192 }
2193 
2194 static const struct nla_policy ip6gre_policy[IFLA_GRE_MAX + 1] = {
2195 	[IFLA_GRE_LINK]        = { .type = NLA_U32 },
2196 	[IFLA_GRE_IFLAGS]      = { .type = NLA_U16 },
2197 	[IFLA_GRE_OFLAGS]      = { .type = NLA_U16 },
2198 	[IFLA_GRE_IKEY]        = { .type = NLA_U32 },
2199 	[IFLA_GRE_OKEY]        = { .type = NLA_U32 },
2200 	[IFLA_GRE_LOCAL]       = { .len = sizeof_field(struct ipv6hdr, saddr) },
2201 	[IFLA_GRE_REMOTE]      = { .len = sizeof_field(struct ipv6hdr, daddr) },
2202 	[IFLA_GRE_TTL]         = { .type = NLA_U8 },
2203 	[IFLA_GRE_ENCAP_LIMIT] = { .type = NLA_U8 },
2204 	[IFLA_GRE_FLOWINFO]    = { .type = NLA_U32 },
2205 	[IFLA_GRE_FLAGS]       = { .type = NLA_U32 },
2206 	[IFLA_GRE_ENCAP_TYPE]   = { .type = NLA_U16 },
2207 	[IFLA_GRE_ENCAP_FLAGS]  = { .type = NLA_U16 },
2208 	[IFLA_GRE_ENCAP_SPORT]  = { .type = NLA_U16 },
2209 	[IFLA_GRE_ENCAP_DPORT]  = { .type = NLA_U16 },
2210 	[IFLA_GRE_COLLECT_METADATA] = { .type = NLA_FLAG },
2211 	[IFLA_GRE_FWMARK]       = { .type = NLA_U32 },
2212 	[IFLA_GRE_ERSPAN_INDEX] = { .type = NLA_U32 },
2213 	[IFLA_GRE_ERSPAN_VER]	= { .type = NLA_U8 },
2214 	[IFLA_GRE_ERSPAN_DIR]	= { .type = NLA_U8 },
2215 	[IFLA_GRE_ERSPAN_HWID]	= { .type = NLA_U16 },
2216 };
2217 
2218 static void ip6erspan_tap_setup(struct net_device *dev)
2219 {
2220 	ether_setup(dev);
2221 
2222 	dev->max_mtu = 0;
2223 	dev->netdev_ops = &ip6erspan_netdev_ops;
2224 	dev->needs_free_netdev = true;
2225 	dev->priv_destructor = ip6gre_dev_free;
2226 
2227 	dev->priv_flags &= ~IFF_TX_SKB_SHARING;
2228 	dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
2229 	netif_keep_dst(dev);
2230 }
2231 
2232 static int ip6erspan_newlink(struct net *src_net, struct net_device *dev,
2233 			     struct nlattr *tb[], struct nlattr *data[],
2234 			     struct netlink_ext_ack *extack)
2235 {
2236 	struct ip6_tnl *nt = netdev_priv(dev);
2237 	struct net *net = dev_net(dev);
2238 	struct ip6gre_net *ign;
2239 	int err;
2240 
2241 	ip6gre_netlink_parms(data, &nt->parms);
2242 	ip6erspan_set_version(data, &nt->parms);
2243 	ign = net_generic(net, ip6gre_net_id);
2244 
2245 	if (nt->parms.collect_md) {
2246 		if (rtnl_dereference(ign->collect_md_tun_erspan))
2247 			return -EEXIST;
2248 	} else {
2249 		if (ip6gre_tunnel_find(net, &nt->parms, dev->type))
2250 			return -EEXIST;
2251 	}
2252 
2253 	err = ip6gre_newlink_common(src_net, dev, tb, data, extack);
2254 	if (!err) {
2255 		ip6erspan_tnl_link_config(nt, !tb[IFLA_MTU]);
2256 		ip6erspan_tunnel_link_md(ign, nt);
2257 		ip6gre_tunnel_link(net_generic(net, ip6gre_net_id), nt);
2258 	}
2259 	return err;
2260 }
2261 
2262 static void ip6erspan_tnl_link_config(struct ip6_tnl *t, int set_mtu)
2263 {
2264 	ip6gre_tnl_link_config_common(t);
2265 	ip6gre_tnl_link_config_route(t, set_mtu, ip6erspan_calc_hlen(t));
2266 }
2267 
2268 static int ip6erspan_tnl_change(struct ip6_tnl *t,
2269 				const struct __ip6_tnl_parm *p, int set_mtu)
2270 {
2271 	ip6gre_tnl_copy_tnl_parm(t, p);
2272 	ip6erspan_tnl_link_config(t, set_mtu);
2273 	return 0;
2274 }
2275 
2276 static int ip6erspan_changelink(struct net_device *dev, struct nlattr *tb[],
2277 				struct nlattr *data[],
2278 				struct netlink_ext_ack *extack)
2279 {
2280 	struct ip6gre_net *ign = net_generic(dev_net(dev), ip6gre_net_id);
2281 	struct __ip6_tnl_parm p;
2282 	struct ip6_tnl *t;
2283 
2284 	t = ip6gre_changelink_common(dev, tb, data, &p, extack);
2285 	if (IS_ERR(t))
2286 		return PTR_ERR(t);
2287 
2288 	ip6erspan_set_version(data, &p);
2289 	ip6gre_tunnel_unlink_md(ign, t);
2290 	ip6gre_tunnel_unlink(ign, t);
2291 	ip6erspan_tnl_change(t, &p, !tb[IFLA_MTU]);
2292 	ip6erspan_tunnel_link_md(ign, t);
2293 	ip6gre_tunnel_link(ign, t);
2294 	return 0;
2295 }
2296 
2297 static struct rtnl_link_ops ip6gre_link_ops __read_mostly = {
2298 	.kind		= "ip6gre",
2299 	.maxtype	= IFLA_GRE_MAX,
2300 	.policy		= ip6gre_policy,
2301 	.priv_size	= sizeof(struct ip6_tnl),
2302 	.setup		= ip6gre_tunnel_setup,
2303 	.validate	= ip6gre_tunnel_validate,
2304 	.newlink	= ip6gre_newlink,
2305 	.changelink	= ip6gre_changelink,
2306 	.dellink	= ip6gre_dellink,
2307 	.get_size	= ip6gre_get_size,
2308 	.fill_info	= ip6gre_fill_info,
2309 	.get_link_net	= ip6_tnl_get_link_net,
2310 };
2311 
2312 static struct rtnl_link_ops ip6gre_tap_ops __read_mostly = {
2313 	.kind		= "ip6gretap",
2314 	.maxtype	= IFLA_GRE_MAX,
2315 	.policy		= ip6gre_policy,
2316 	.priv_size	= sizeof(struct ip6_tnl),
2317 	.setup		= ip6gre_tap_setup,
2318 	.validate	= ip6gre_tap_validate,
2319 	.newlink	= ip6gre_newlink,
2320 	.changelink	= ip6gre_changelink,
2321 	.get_size	= ip6gre_get_size,
2322 	.fill_info	= ip6gre_fill_info,
2323 	.get_link_net	= ip6_tnl_get_link_net,
2324 };
2325 
2326 static struct rtnl_link_ops ip6erspan_tap_ops __read_mostly = {
2327 	.kind		= "ip6erspan",
2328 	.maxtype	= IFLA_GRE_MAX,
2329 	.policy		= ip6gre_policy,
2330 	.priv_size	= sizeof(struct ip6_tnl),
2331 	.setup		= ip6erspan_tap_setup,
2332 	.validate	= ip6erspan_tap_validate,
2333 	.newlink	= ip6erspan_newlink,
2334 	.changelink	= ip6erspan_changelink,
2335 	.get_size	= ip6gre_get_size,
2336 	.fill_info	= ip6gre_fill_info,
2337 	.get_link_net	= ip6_tnl_get_link_net,
2338 };
2339 
2340 /*
2341  *	And now the modules code and kernel interface.
2342  */
2343 
2344 static int __init ip6gre_init(void)
2345 {
2346 	int err;
2347 
2348 	pr_info("GRE over IPv6 tunneling driver\n");
2349 
2350 	err = register_pernet_device(&ip6gre_net_ops);
2351 	if (err < 0)
2352 		return err;
2353 
2354 	err = inet6_add_protocol(&ip6gre_protocol, IPPROTO_GRE);
2355 	if (err < 0) {
2356 		pr_info("%s: can't add protocol\n", __func__);
2357 		goto add_proto_failed;
2358 	}
2359 
2360 	err = rtnl_link_register(&ip6gre_link_ops);
2361 	if (err < 0)
2362 		goto rtnl_link_failed;
2363 
2364 	err = rtnl_link_register(&ip6gre_tap_ops);
2365 	if (err < 0)
2366 		goto tap_ops_failed;
2367 
2368 	err = rtnl_link_register(&ip6erspan_tap_ops);
2369 	if (err < 0)
2370 		goto erspan_link_failed;
2371 
2372 out:
2373 	return err;
2374 
2375 erspan_link_failed:
2376 	rtnl_link_unregister(&ip6gre_tap_ops);
2377 tap_ops_failed:
2378 	rtnl_link_unregister(&ip6gre_link_ops);
2379 rtnl_link_failed:
2380 	inet6_del_protocol(&ip6gre_protocol, IPPROTO_GRE);
2381 add_proto_failed:
2382 	unregister_pernet_device(&ip6gre_net_ops);
2383 	goto out;
2384 }
2385 
2386 static void __exit ip6gre_fini(void)
2387 {
2388 	rtnl_link_unregister(&ip6gre_tap_ops);
2389 	rtnl_link_unregister(&ip6gre_link_ops);
2390 	rtnl_link_unregister(&ip6erspan_tap_ops);
2391 	inet6_del_protocol(&ip6gre_protocol, IPPROTO_GRE);
2392 	unregister_pernet_device(&ip6gre_net_ops);
2393 }
2394 
2395 module_init(ip6gre_init);
2396 module_exit(ip6gre_fini);
2397 MODULE_LICENSE("GPL");
2398 MODULE_AUTHOR("D. Kozlov (xeb@mail.ru)");
2399 MODULE_DESCRIPTION("GRE over IPv6 tunneling device");
2400 MODULE_ALIAS_RTNL_LINK("ip6gre");
2401 MODULE_ALIAS_RTNL_LINK("ip6gretap");
2402 MODULE_ALIAS_RTNL_LINK("ip6erspan");
2403 MODULE_ALIAS_NETDEV("ip6gre0");
2404