xref: /linux/net/ipv6/ip6_gre.c (revision 1a9239bb4253f9076b5b4b2a1a4e8d7defd77a95)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *	GRE over IPv6 protocol decoder.
4  *
5  *	Authors: Dmitry Kozlov (xeb@mail.ru)
6  */
7 
8 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
9 
10 #include <linux/capability.h>
11 #include <linux/module.h>
12 #include <linux/types.h>
13 #include <linux/kernel.h>
14 #include <linux/slab.h>
15 #include <linux/uaccess.h>
16 #include <linux/skbuff.h>
17 #include <linux/netdevice.h>
18 #include <linux/in.h>
19 #include <linux/tcp.h>
20 #include <linux/udp.h>
21 #include <linux/if_arp.h>
22 #include <linux/init.h>
23 #include <linux/in6.h>
24 #include <linux/inetdevice.h>
25 #include <linux/igmp.h>
26 #include <linux/netfilter_ipv4.h>
27 #include <linux/etherdevice.h>
28 #include <linux/if_ether.h>
29 #include <linux/hash.h>
30 #include <linux/if_tunnel.h>
31 #include <linux/ip6_tunnel.h>
32 
33 #include <net/sock.h>
34 #include <net/ip.h>
35 #include <net/ip_tunnels.h>
36 #include <net/icmp.h>
37 #include <net/protocol.h>
38 #include <net/addrconf.h>
39 #include <net/arp.h>
40 #include <net/checksum.h>
41 #include <net/dsfield.h>
42 #include <net/inet_ecn.h>
43 #include <net/xfrm.h>
44 #include <net/net_namespace.h>
45 #include <net/netns/generic.h>
46 #include <net/netdev_lock.h>
47 #include <net/rtnetlink.h>
48 
49 #include <net/ipv6.h>
50 #include <net/ip6_fib.h>
51 #include <net/ip6_route.h>
52 #include <net/ip6_tunnel.h>
53 #include <net/gre.h>
54 #include <net/erspan.h>
55 #include <net/dst_metadata.h>
56 
57 
58 static bool log_ecn_error = true;
59 module_param(log_ecn_error, bool, 0644);
60 MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN");
61 
62 #define IP6_GRE_HASH_SIZE_SHIFT  5
63 #define IP6_GRE_HASH_SIZE (1 << IP6_GRE_HASH_SIZE_SHIFT)
64 
65 static unsigned int ip6gre_net_id __read_mostly;
66 struct ip6gre_net {
67 	struct ip6_tnl __rcu *tunnels[4][IP6_GRE_HASH_SIZE];
68 
69 	struct ip6_tnl __rcu *collect_md_tun;
70 	struct ip6_tnl __rcu *collect_md_tun_erspan;
71 	struct net_device *fb_tunnel_dev;
72 };
73 
74 static struct rtnl_link_ops ip6gre_link_ops __read_mostly;
75 static struct rtnl_link_ops ip6gre_tap_ops __read_mostly;
76 static struct rtnl_link_ops ip6erspan_tap_ops __read_mostly;
77 static int ip6gre_tunnel_init(struct net_device *dev);
78 static void ip6gre_tunnel_setup(struct net_device *dev);
79 static void ip6gre_tunnel_link(struct ip6gre_net *ign, struct ip6_tnl *t);
80 static void ip6gre_tnl_link_config(struct ip6_tnl *t, int set_mtu);
81 static void ip6erspan_tnl_link_config(struct ip6_tnl *t, int set_mtu);
82 
83 /* Tunnel hash table */
84 
85 /*
86    4 hash tables:
87 
88    3: (remote,local)
89    2: (remote,*)
90    1: (*,local)
91    0: (*,*)
92 
93    We require exact key match i.e. if a key is present in packet
94    it will match only tunnel with the same key; if it is not present,
95    it will match only keyless tunnel.
96 
97    All keysless packets, if not matched configured keyless tunnels
98    will match fallback tunnel.
99  */
100 
101 #define HASH_KEY(key) (((__force u32)key^((__force u32)key>>4))&(IP6_GRE_HASH_SIZE - 1))
HASH_ADDR(const struct in6_addr * addr)102 static u32 HASH_ADDR(const struct in6_addr *addr)
103 {
104 	u32 hash = ipv6_addr_hash(addr);
105 
106 	return hash_32(hash, IP6_GRE_HASH_SIZE_SHIFT);
107 }
108 
109 #define tunnels_r_l	tunnels[3]
110 #define tunnels_r	tunnels[2]
111 #define tunnels_l	tunnels[1]
112 #define tunnels_wc	tunnels[0]
113 
114 /* Given src, dst and key, find appropriate for input tunnel. */
115 
ip6gre_tunnel_lookup(struct net_device * dev,const struct in6_addr * remote,const struct in6_addr * local,__be32 key,__be16 gre_proto)116 static struct ip6_tnl *ip6gre_tunnel_lookup(struct net_device *dev,
117 		const struct in6_addr *remote, const struct in6_addr *local,
118 		__be32 key, __be16 gre_proto)
119 {
120 	struct net *net = dev_net(dev);
121 	int link = dev->ifindex;
122 	unsigned int h0 = HASH_ADDR(remote);
123 	unsigned int h1 = HASH_KEY(key);
124 	struct ip6_tnl *t, *cand = NULL;
125 	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
126 	int dev_type = (gre_proto == htons(ETH_P_TEB) ||
127 			gre_proto == htons(ETH_P_ERSPAN) ||
128 			gre_proto == htons(ETH_P_ERSPAN2)) ?
129 		       ARPHRD_ETHER : ARPHRD_IP6GRE;
130 	int score, cand_score = 4;
131 	struct net_device *ndev;
132 
133 	for_each_ip_tunnel_rcu(t, ign->tunnels_r_l[h0 ^ h1]) {
134 		if (!ipv6_addr_equal(local, &t->parms.laddr) ||
135 		    !ipv6_addr_equal(remote, &t->parms.raddr) ||
136 		    key != t->parms.i_key ||
137 		    !(t->dev->flags & IFF_UP))
138 			continue;
139 
140 		if (t->dev->type != ARPHRD_IP6GRE &&
141 		    t->dev->type != dev_type)
142 			continue;
143 
144 		score = 0;
145 		if (t->parms.link != link)
146 			score |= 1;
147 		if (t->dev->type != dev_type)
148 			score |= 2;
149 		if (score == 0)
150 			return t;
151 
152 		if (score < cand_score) {
153 			cand = t;
154 			cand_score = score;
155 		}
156 	}
157 
158 	for_each_ip_tunnel_rcu(t, ign->tunnels_r[h0 ^ h1]) {
159 		if (!ipv6_addr_equal(remote, &t->parms.raddr) ||
160 		    key != t->parms.i_key ||
161 		    !(t->dev->flags & IFF_UP))
162 			continue;
163 
164 		if (t->dev->type != ARPHRD_IP6GRE &&
165 		    t->dev->type != dev_type)
166 			continue;
167 
168 		score = 0;
169 		if (t->parms.link != link)
170 			score |= 1;
171 		if (t->dev->type != dev_type)
172 			score |= 2;
173 		if (score == 0)
174 			return t;
175 
176 		if (score < cand_score) {
177 			cand = t;
178 			cand_score = score;
179 		}
180 	}
181 
182 	for_each_ip_tunnel_rcu(t, ign->tunnels_l[h1]) {
183 		if ((!ipv6_addr_equal(local, &t->parms.laddr) &&
184 			  (!ipv6_addr_equal(local, &t->parms.raddr) ||
185 				 !ipv6_addr_is_multicast(local))) ||
186 		    key != t->parms.i_key ||
187 		    !(t->dev->flags & IFF_UP))
188 			continue;
189 
190 		if (t->dev->type != ARPHRD_IP6GRE &&
191 		    t->dev->type != dev_type)
192 			continue;
193 
194 		score = 0;
195 		if (t->parms.link != link)
196 			score |= 1;
197 		if (t->dev->type != dev_type)
198 			score |= 2;
199 		if (score == 0)
200 			return t;
201 
202 		if (score < cand_score) {
203 			cand = t;
204 			cand_score = score;
205 		}
206 	}
207 
208 	for_each_ip_tunnel_rcu(t, ign->tunnels_wc[h1]) {
209 		if (t->parms.i_key != key ||
210 		    !(t->dev->flags & IFF_UP))
211 			continue;
212 
213 		if (t->dev->type != ARPHRD_IP6GRE &&
214 		    t->dev->type != dev_type)
215 			continue;
216 
217 		score = 0;
218 		if (t->parms.link != link)
219 			score |= 1;
220 		if (t->dev->type != dev_type)
221 			score |= 2;
222 		if (score == 0)
223 			return t;
224 
225 		if (score < cand_score) {
226 			cand = t;
227 			cand_score = score;
228 		}
229 	}
230 
231 	if (cand)
232 		return cand;
233 
234 	if (gre_proto == htons(ETH_P_ERSPAN) ||
235 	    gre_proto == htons(ETH_P_ERSPAN2))
236 		t = rcu_dereference(ign->collect_md_tun_erspan);
237 	else
238 		t = rcu_dereference(ign->collect_md_tun);
239 
240 	if (t && t->dev->flags & IFF_UP)
241 		return t;
242 
243 	ndev = READ_ONCE(ign->fb_tunnel_dev);
244 	if (ndev && ndev->flags & IFF_UP)
245 		return netdev_priv(ndev);
246 
247 	return NULL;
248 }
249 
__ip6gre_bucket(struct ip6gre_net * ign,const struct __ip6_tnl_parm * p)250 static struct ip6_tnl __rcu **__ip6gre_bucket(struct ip6gre_net *ign,
251 		const struct __ip6_tnl_parm *p)
252 {
253 	const struct in6_addr *remote = &p->raddr;
254 	const struct in6_addr *local = &p->laddr;
255 	unsigned int h = HASH_KEY(p->i_key);
256 	int prio = 0;
257 
258 	if (!ipv6_addr_any(local))
259 		prio |= 1;
260 	if (!ipv6_addr_any(remote) && !ipv6_addr_is_multicast(remote)) {
261 		prio |= 2;
262 		h ^= HASH_ADDR(remote);
263 	}
264 
265 	return &ign->tunnels[prio][h];
266 }
267 
ip6gre_tunnel_link_md(struct ip6gre_net * ign,struct ip6_tnl * t)268 static void ip6gre_tunnel_link_md(struct ip6gre_net *ign, struct ip6_tnl *t)
269 {
270 	if (t->parms.collect_md)
271 		rcu_assign_pointer(ign->collect_md_tun, t);
272 }
273 
ip6erspan_tunnel_link_md(struct ip6gre_net * ign,struct ip6_tnl * t)274 static void ip6erspan_tunnel_link_md(struct ip6gre_net *ign, struct ip6_tnl *t)
275 {
276 	if (t->parms.collect_md)
277 		rcu_assign_pointer(ign->collect_md_tun_erspan, t);
278 }
279 
ip6gre_tunnel_unlink_md(struct ip6gre_net * ign,struct ip6_tnl * t)280 static void ip6gre_tunnel_unlink_md(struct ip6gre_net *ign, struct ip6_tnl *t)
281 {
282 	if (t->parms.collect_md)
283 		rcu_assign_pointer(ign->collect_md_tun, NULL);
284 }
285 
ip6erspan_tunnel_unlink_md(struct ip6gre_net * ign,struct ip6_tnl * t)286 static void ip6erspan_tunnel_unlink_md(struct ip6gre_net *ign,
287 				       struct ip6_tnl *t)
288 {
289 	if (t->parms.collect_md)
290 		rcu_assign_pointer(ign->collect_md_tun_erspan, NULL);
291 }
292 
ip6gre_bucket(struct ip6gre_net * ign,const struct ip6_tnl * t)293 static inline struct ip6_tnl __rcu **ip6gre_bucket(struct ip6gre_net *ign,
294 		const struct ip6_tnl *t)
295 {
296 	return __ip6gre_bucket(ign, &t->parms);
297 }
298 
ip6gre_tunnel_link(struct ip6gre_net * ign,struct ip6_tnl * t)299 static void ip6gre_tunnel_link(struct ip6gre_net *ign, struct ip6_tnl *t)
300 {
301 	struct ip6_tnl __rcu **tp = ip6gre_bucket(ign, t);
302 
303 	rcu_assign_pointer(t->next, rtnl_dereference(*tp));
304 	rcu_assign_pointer(*tp, t);
305 }
306 
ip6gre_tunnel_unlink(struct ip6gre_net * ign,struct ip6_tnl * t)307 static void ip6gre_tunnel_unlink(struct ip6gre_net *ign, struct ip6_tnl *t)
308 {
309 	struct ip6_tnl __rcu **tp;
310 	struct ip6_tnl *iter;
311 
312 	for (tp = ip6gre_bucket(ign, t);
313 	     (iter = rtnl_dereference(*tp)) != NULL;
314 	     tp = &iter->next) {
315 		if (t == iter) {
316 			rcu_assign_pointer(*tp, t->next);
317 			break;
318 		}
319 	}
320 }
321 
ip6gre_tunnel_find(struct net * net,const struct __ip6_tnl_parm * parms,int type)322 static struct ip6_tnl *ip6gre_tunnel_find(struct net *net,
323 					   const struct __ip6_tnl_parm *parms,
324 					   int type)
325 {
326 	const struct in6_addr *remote = &parms->raddr;
327 	const struct in6_addr *local = &parms->laddr;
328 	__be32 key = parms->i_key;
329 	int link = parms->link;
330 	struct ip6_tnl *t;
331 	struct ip6_tnl __rcu **tp;
332 	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
333 
334 	for (tp = __ip6gre_bucket(ign, parms);
335 	     (t = rtnl_dereference(*tp)) != NULL;
336 	     tp = &t->next)
337 		if (ipv6_addr_equal(local, &t->parms.laddr) &&
338 		    ipv6_addr_equal(remote, &t->parms.raddr) &&
339 		    key == t->parms.i_key &&
340 		    link == t->parms.link &&
341 		    type == t->dev->type)
342 			break;
343 
344 	return t;
345 }
346 
ip6gre_tunnel_locate(struct net * net,const struct __ip6_tnl_parm * parms,int create)347 static struct ip6_tnl *ip6gre_tunnel_locate(struct net *net,
348 		const struct __ip6_tnl_parm *parms, int create)
349 {
350 	struct ip6_tnl *t, *nt;
351 	struct net_device *dev;
352 	char name[IFNAMSIZ];
353 	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
354 
355 	t = ip6gre_tunnel_find(net, parms, ARPHRD_IP6GRE);
356 	if (t && create)
357 		return NULL;
358 	if (t || !create)
359 		return t;
360 
361 	if (parms->name[0]) {
362 		if (!dev_valid_name(parms->name))
363 			return NULL;
364 		strscpy(name, parms->name, IFNAMSIZ);
365 	} else {
366 		strcpy(name, "ip6gre%d");
367 	}
368 	dev = alloc_netdev(sizeof(*t), name, NET_NAME_UNKNOWN,
369 			   ip6gre_tunnel_setup);
370 	if (!dev)
371 		return NULL;
372 
373 	dev_net_set(dev, net);
374 
375 	nt = netdev_priv(dev);
376 	nt->parms = *parms;
377 	dev->rtnl_link_ops = &ip6gre_link_ops;
378 
379 	nt->dev = dev;
380 	nt->net = dev_net(dev);
381 
382 	if (register_netdevice(dev) < 0)
383 		goto failed_free;
384 
385 	ip6gre_tnl_link_config(nt, 1);
386 	ip6gre_tunnel_link(ign, nt);
387 	return nt;
388 
389 failed_free:
390 	free_netdev(dev);
391 	return NULL;
392 }
393 
ip6erspan_tunnel_uninit(struct net_device * dev)394 static void ip6erspan_tunnel_uninit(struct net_device *dev)
395 {
396 	struct ip6_tnl *t = netdev_priv(dev);
397 	struct ip6gre_net *ign = net_generic(t->net, ip6gre_net_id);
398 
399 	ip6erspan_tunnel_unlink_md(ign, t);
400 	ip6gre_tunnel_unlink(ign, t);
401 	dst_cache_reset(&t->dst_cache);
402 	netdev_put(dev, &t->dev_tracker);
403 }
404 
ip6gre_tunnel_uninit(struct net_device * dev)405 static void ip6gre_tunnel_uninit(struct net_device *dev)
406 {
407 	struct ip6_tnl *t = netdev_priv(dev);
408 	struct ip6gre_net *ign = net_generic(t->net, ip6gre_net_id);
409 
410 	ip6gre_tunnel_unlink_md(ign, t);
411 	ip6gre_tunnel_unlink(ign, t);
412 	if (ign->fb_tunnel_dev == dev)
413 		WRITE_ONCE(ign->fb_tunnel_dev, NULL);
414 	dst_cache_reset(&t->dst_cache);
415 	netdev_put(dev, &t->dev_tracker);
416 }
417 
418 
ip6gre_err(struct sk_buff * skb,struct inet6_skb_parm * opt,u8 type,u8 code,int offset,__be32 info)419 static int ip6gre_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
420 		       u8 type, u8 code, int offset, __be32 info)
421 {
422 	struct net *net = dev_net(skb->dev);
423 	const struct ipv6hdr *ipv6h;
424 	struct tnl_ptk_info tpi;
425 	struct ip6_tnl *t;
426 
427 	if (gre_parse_header(skb, &tpi, NULL, htons(ETH_P_IPV6),
428 			     offset) < 0)
429 		return -EINVAL;
430 
431 	ipv6h = (const struct ipv6hdr *)skb->data;
432 	t = ip6gre_tunnel_lookup(skb->dev, &ipv6h->daddr, &ipv6h->saddr,
433 				 tpi.key, tpi.proto);
434 	if (!t)
435 		return -ENOENT;
436 
437 	switch (type) {
438 	case ICMPV6_DEST_UNREACH:
439 		net_dbg_ratelimited("%s: Path to destination invalid or inactive!\n",
440 				    t->parms.name);
441 		if (code != ICMPV6_PORT_UNREACH)
442 			break;
443 		return 0;
444 	case ICMPV6_TIME_EXCEED:
445 		if (code == ICMPV6_EXC_HOPLIMIT) {
446 			net_dbg_ratelimited("%s: Too small hop limit or routing loop in tunnel!\n",
447 					    t->parms.name);
448 			break;
449 		}
450 		return 0;
451 	case ICMPV6_PARAMPROB: {
452 		struct ipv6_tlv_tnl_enc_lim *tel;
453 		__u32 teli;
454 
455 		teli = 0;
456 		if (code == ICMPV6_HDR_FIELD)
457 			teli = ip6_tnl_parse_tlv_enc_lim(skb, skb->data);
458 
459 		if (teli && teli == be32_to_cpu(info) - 2) {
460 			tel = (struct ipv6_tlv_tnl_enc_lim *) &skb->data[teli];
461 			if (tel->encap_limit == 0) {
462 				net_dbg_ratelimited("%s: Too small encapsulation limit or routing loop in tunnel!\n",
463 						    t->parms.name);
464 			}
465 		} else {
466 			net_dbg_ratelimited("%s: Recipient unable to parse tunneled packet!\n",
467 					    t->parms.name);
468 		}
469 		return 0;
470 	}
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 
ip6gre_rcv(struct sk_buff * skb,const struct tnl_ptk_info * tpi)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 			IP_TUNNEL_DECLARE_FLAGS(flags);
501 			struct metadata_dst *tun_dst;
502 			__be64 tun_id;
503 
504 			ip_tunnel_flags_copy(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 
ip6erspan_rcv(struct sk_buff * skb,struct tnl_ptk_info * tpi,int gre_hdr_len)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 	if (unlikely(!pskb_may_pull(skb, sizeof(*ershdr))))
533 		return PACKET_REJECT;
534 
535 	ipv6h = ipv6_hdr(skb);
536 	ershdr = (struct erspan_base_hdr *)skb->data;
537 	ver = ershdr->ver;
538 
539 	tunnel = ip6gre_tunnel_lookup(skb->dev,
540 				      &ipv6h->saddr, &ipv6h->daddr, tpi->key,
541 				      tpi->proto);
542 	if (tunnel) {
543 		int len = erspan_hdr_len(ver);
544 
545 		if (unlikely(!pskb_may_pull(skb, len)))
546 			return PACKET_REJECT;
547 
548 		if (__iptunnel_pull_header(skb, len,
549 					   htons(ETH_P_TEB),
550 					   false, false) < 0)
551 			return PACKET_REJECT;
552 
553 		if (tunnel->parms.collect_md) {
554 			struct erspan_metadata *pkt_md, *md;
555 			IP_TUNNEL_DECLARE_FLAGS(flags);
556 			struct metadata_dst *tun_dst;
557 			struct ip_tunnel_info *info;
558 			unsigned char *gh;
559 			__be64 tun_id;
560 
561 			__set_bit(IP_TUNNEL_KEY_BIT, tpi->flags);
562 			ip_tunnel_flags_copy(flags, tpi->flags);
563 			tun_id = key32_to_tunnel_id(tpi->key);
564 
565 			tun_dst = ipv6_tun_rx_dst(skb, flags, tun_id,
566 						  sizeof(*md));
567 			if (!tun_dst)
568 				return PACKET_REJECT;
569 
570 			/* skb can be uncloned in __iptunnel_pull_header, so
571 			 * old pkt_md is no longer valid and we need to reset
572 			 * it
573 			 */
574 			gh = skb_network_header(skb) +
575 			     skb_network_header_len(skb);
576 			pkt_md = (struct erspan_metadata *)(gh + gre_hdr_len +
577 							    sizeof(*ershdr));
578 			info = &tun_dst->u.tun_info;
579 			md = ip_tunnel_info_opts(info);
580 			md->version = ver;
581 			md2 = &md->u.md2;
582 			memcpy(md2, pkt_md, ver == 1 ? ERSPAN_V1_MDSIZE :
583 						       ERSPAN_V2_MDSIZE);
584 			__set_bit(IP_TUNNEL_ERSPAN_OPT_BIT,
585 				  info->key.tun_flags);
586 			info->options_len = sizeof(*md);
587 
588 			ip6_tnl_rcv(tunnel, skb, tpi, tun_dst, log_ecn_error);
589 
590 		} else {
591 			ip6_tnl_rcv(tunnel, skb, tpi, NULL, log_ecn_error);
592 		}
593 
594 		return PACKET_RCVD;
595 	}
596 
597 	return PACKET_REJECT;
598 }
599 
gre_rcv(struct sk_buff * skb)600 static int gre_rcv(struct sk_buff *skb)
601 {
602 	struct tnl_ptk_info tpi;
603 	bool csum_err = false;
604 	int hdr_len;
605 
606 	hdr_len = gre_parse_header(skb, &tpi, &csum_err, htons(ETH_P_IPV6), 0);
607 	if (hdr_len < 0)
608 		goto drop;
609 
610 	if (iptunnel_pull_header(skb, hdr_len, tpi.proto, false))
611 		goto drop;
612 
613 	if (unlikely(tpi.proto == htons(ETH_P_ERSPAN) ||
614 		     tpi.proto == htons(ETH_P_ERSPAN2))) {
615 		if (ip6erspan_rcv(skb, &tpi, hdr_len) == PACKET_RCVD)
616 			return 0;
617 		goto out;
618 	}
619 
620 	if (ip6gre_rcv(skb, &tpi) == PACKET_RCVD)
621 		return 0;
622 
623 out:
624 	icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0);
625 drop:
626 	kfree_skb(skb);
627 	return 0;
628 }
629 
gre_handle_offloads(struct sk_buff * skb,bool csum)630 static int gre_handle_offloads(struct sk_buff *skb, bool csum)
631 {
632 	return iptunnel_handle_offloads(skb,
633 					csum ? SKB_GSO_GRE_CSUM : SKB_GSO_GRE);
634 }
635 
prepare_ip6gre_xmit_ipv4(struct sk_buff * skb,struct net_device * dev,struct flowi6 * fl6,__u8 * dsfield,int * encap_limit)636 static void prepare_ip6gre_xmit_ipv4(struct sk_buff *skb,
637 				     struct net_device *dev,
638 				     struct flowi6 *fl6, __u8 *dsfield,
639 				     int *encap_limit)
640 {
641 	const struct iphdr *iph = ip_hdr(skb);
642 	struct ip6_tnl *t = netdev_priv(dev);
643 
644 	if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
645 		*encap_limit = t->parms.encap_limit;
646 
647 	memcpy(fl6, &t->fl.u.ip6, sizeof(*fl6));
648 
649 	if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
650 		*dsfield = ipv4_get_dsfield(iph);
651 	else
652 		*dsfield = ip6_tclass(t->parms.flowinfo);
653 
654 	if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
655 		fl6->flowi6_mark = skb->mark;
656 	else
657 		fl6->flowi6_mark = t->parms.fwmark;
658 
659 	fl6->flowi6_uid = sock_net_uid(dev_net(dev), NULL);
660 }
661 
prepare_ip6gre_xmit_ipv6(struct sk_buff * skb,struct net_device * dev,struct flowi6 * fl6,__u8 * dsfield,int * encap_limit)662 static int prepare_ip6gre_xmit_ipv6(struct sk_buff *skb,
663 				    struct net_device *dev,
664 				    struct flowi6 *fl6, __u8 *dsfield,
665 				    int *encap_limit)
666 {
667 	struct ipv6hdr *ipv6h;
668 	struct ip6_tnl *t = netdev_priv(dev);
669 	__u16 offset;
670 
671 	offset = ip6_tnl_parse_tlv_enc_lim(skb, skb_network_header(skb));
672 	/* ip6_tnl_parse_tlv_enc_lim() might have reallocated skb->head */
673 	ipv6h = ipv6_hdr(skb);
674 
675 	if (offset > 0) {
676 		struct ipv6_tlv_tnl_enc_lim *tel;
677 
678 		tel = (struct ipv6_tlv_tnl_enc_lim *)&skb_network_header(skb)[offset];
679 		if (tel->encap_limit == 0) {
680 			icmpv6_ndo_send(skb, ICMPV6_PARAMPROB,
681 					ICMPV6_HDR_FIELD, offset + 2);
682 			return -1;
683 		}
684 		*encap_limit = tel->encap_limit - 1;
685 	} else if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) {
686 		*encap_limit = t->parms.encap_limit;
687 	}
688 
689 	memcpy(fl6, &t->fl.u.ip6, sizeof(*fl6));
690 
691 	if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
692 		*dsfield = ipv6_get_dsfield(ipv6h);
693 	else
694 		*dsfield = ip6_tclass(t->parms.flowinfo);
695 
696 	if (t->parms.flags & IP6_TNL_F_USE_ORIG_FLOWLABEL)
697 		fl6->flowlabel |= ip6_flowlabel(ipv6h);
698 
699 	if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
700 		fl6->flowi6_mark = skb->mark;
701 	else
702 		fl6->flowi6_mark = t->parms.fwmark;
703 
704 	fl6->flowi6_uid = sock_net_uid(dev_net(dev), NULL);
705 
706 	return 0;
707 }
708 
prepare_ip6gre_xmit_other(struct sk_buff * skb,struct net_device * dev,struct flowi6 * fl6,__u8 * dsfield,int * encap_limit)709 static int prepare_ip6gre_xmit_other(struct sk_buff *skb,
710 				     struct net_device *dev,
711 				     struct flowi6 *fl6, __u8 *dsfield,
712 				     int *encap_limit)
713 {
714 	struct ip6_tnl *t = netdev_priv(dev);
715 
716 	if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
717 		*encap_limit = t->parms.encap_limit;
718 
719 	memcpy(fl6, &t->fl.u.ip6, sizeof(*fl6));
720 
721 	if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
722 		*dsfield = 0;
723 	else
724 		*dsfield = ip6_tclass(t->parms.flowinfo);
725 
726 	if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
727 		fl6->flowi6_mark = skb->mark;
728 	else
729 		fl6->flowi6_mark = t->parms.fwmark;
730 
731 	fl6->flowi6_uid = sock_net_uid(dev_net(dev), NULL);
732 
733 	return 0;
734 }
735 
skb_tunnel_info_txcheck(struct sk_buff * skb)736 static struct ip_tunnel_info *skb_tunnel_info_txcheck(struct sk_buff *skb)
737 {
738 	struct ip_tunnel_info *tun_info;
739 
740 	tun_info = skb_tunnel_info(skb);
741 	if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX)))
742 		return ERR_PTR(-EINVAL);
743 
744 	return tun_info;
745 }
746 
__gre6_xmit(struct sk_buff * skb,struct net_device * dev,__u8 dsfield,struct flowi6 * fl6,int encap_limit,__u32 * pmtu,__be16 proto)747 static netdev_tx_t __gre6_xmit(struct sk_buff *skb,
748 			       struct net_device *dev, __u8 dsfield,
749 			       struct flowi6 *fl6, int encap_limit,
750 			       __u32 *pmtu, __be16 proto)
751 {
752 	struct ip6_tnl *tunnel = netdev_priv(dev);
753 	IP_TUNNEL_DECLARE_FLAGS(flags);
754 	__be16 protocol;
755 
756 	if (dev->type == ARPHRD_ETHER)
757 		IPCB(skb)->flags = 0;
758 
759 	if (dev->header_ops && dev->type == ARPHRD_IP6GRE)
760 		fl6->daddr = ((struct ipv6hdr *)skb->data)->daddr;
761 	else
762 		fl6->daddr = tunnel->parms.raddr;
763 
764 	/* Push GRE header. */
765 	protocol = (dev->type == ARPHRD_ETHER) ? htons(ETH_P_TEB) : proto;
766 
767 	if (tunnel->parms.collect_md) {
768 		struct ip_tunnel_info *tun_info;
769 		const struct ip_tunnel_key *key;
770 		int tun_hlen;
771 
772 		tun_info = skb_tunnel_info_txcheck(skb);
773 		if (IS_ERR(tun_info) ||
774 		    unlikely(ip_tunnel_info_af(tun_info) != AF_INET6))
775 			return -EINVAL;
776 
777 		key = &tun_info->key;
778 		memset(fl6, 0, sizeof(*fl6));
779 		fl6->flowi6_proto = IPPROTO_GRE;
780 		fl6->daddr = key->u.ipv6.dst;
781 		fl6->flowlabel = key->label;
782 		fl6->flowi6_uid = sock_net_uid(dev_net(dev), NULL);
783 		fl6->fl6_gre_key = tunnel_id_to_key32(key->tun_id);
784 
785 		dsfield = key->tos;
786 		ip_tunnel_flags_zero(flags);
787 		__set_bit(IP_TUNNEL_CSUM_BIT, flags);
788 		__set_bit(IP_TUNNEL_KEY_BIT, flags);
789 		__set_bit(IP_TUNNEL_SEQ_BIT, flags);
790 		ip_tunnel_flags_and(flags, flags, key->tun_flags);
791 		tun_hlen = gre_calc_hlen(flags);
792 
793 		if (skb_cow_head(skb, dev->needed_headroom ?: tun_hlen + tunnel->encap_hlen))
794 			return -ENOMEM;
795 
796 		gre_build_header(skb, tun_hlen,
797 				 flags, protocol,
798 				 tunnel_id_to_key32(tun_info->key.tun_id),
799 				 test_bit(IP_TUNNEL_SEQ_BIT, flags) ?
800 				 htonl(atomic_fetch_inc(&tunnel->o_seqno)) :
801 				 0);
802 
803 	} else {
804 		if (skb_cow_head(skb, dev->needed_headroom ?: tunnel->hlen))
805 			return -ENOMEM;
806 
807 		ip_tunnel_flags_copy(flags, tunnel->parms.o_flags);
808 
809 		gre_build_header(skb, tunnel->tun_hlen, flags,
810 				 protocol, tunnel->parms.o_key,
811 				 test_bit(IP_TUNNEL_SEQ_BIT, flags) ?
812 				 htonl(atomic_fetch_inc(&tunnel->o_seqno)) :
813 				 0);
814 	}
815 
816 	return ip6_tnl_xmit(skb, dev, dsfield, fl6, encap_limit, pmtu,
817 			    NEXTHDR_GRE);
818 }
819 
ip6gre_xmit_ipv4(struct sk_buff * skb,struct net_device * dev)820 static inline int ip6gre_xmit_ipv4(struct sk_buff *skb, struct net_device *dev)
821 {
822 	struct ip6_tnl *t = netdev_priv(dev);
823 	int encap_limit = -1;
824 	struct flowi6 fl6;
825 	__u8 dsfield = 0;
826 	__u32 mtu;
827 	int err;
828 
829 	memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
830 
831 	if (!t->parms.collect_md)
832 		prepare_ip6gre_xmit_ipv4(skb, dev, &fl6,
833 					 &dsfield, &encap_limit);
834 
835 	err = gre_handle_offloads(skb, test_bit(IP_TUNNEL_CSUM_BIT,
836 						t->parms.o_flags));
837 	if (err)
838 		return -1;
839 
840 	err = __gre6_xmit(skb, dev, dsfield, &fl6, encap_limit, &mtu,
841 			  skb->protocol);
842 	if (err != 0) {
843 		/* XXX: send ICMP error even if DF is not set. */
844 		if (err == -EMSGSIZE)
845 			icmp_ndo_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
846 				      htonl(mtu));
847 		return -1;
848 	}
849 
850 	return 0;
851 }
852 
ip6gre_xmit_ipv6(struct sk_buff * skb,struct net_device * dev)853 static inline int ip6gre_xmit_ipv6(struct sk_buff *skb, struct net_device *dev)
854 {
855 	struct ip6_tnl *t = netdev_priv(dev);
856 	struct ipv6hdr *ipv6h = ipv6_hdr(skb);
857 	int encap_limit = -1;
858 	struct flowi6 fl6;
859 	__u8 dsfield = 0;
860 	__u32 mtu;
861 	int err;
862 
863 	if (ipv6_addr_equal(&t->parms.raddr, &ipv6h->saddr))
864 		return -1;
865 
866 	if (!t->parms.collect_md &&
867 	    prepare_ip6gre_xmit_ipv6(skb, dev, &fl6, &dsfield, &encap_limit))
868 		return -1;
869 
870 	if (gre_handle_offloads(skb, test_bit(IP_TUNNEL_CSUM_BIT,
871 					      t->parms.o_flags)))
872 		return -1;
873 
874 	err = __gre6_xmit(skb, dev, dsfield, &fl6, encap_limit,
875 			  &mtu, skb->protocol);
876 	if (err != 0) {
877 		if (err == -EMSGSIZE)
878 			icmpv6_ndo_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
879 		return -1;
880 	}
881 
882 	return 0;
883 }
884 
ip6gre_xmit_other(struct sk_buff * skb,struct net_device * dev)885 static int ip6gre_xmit_other(struct sk_buff *skb, struct net_device *dev)
886 {
887 	struct ip6_tnl *t = netdev_priv(dev);
888 	int encap_limit = -1;
889 	struct flowi6 fl6;
890 	__u8 dsfield = 0;
891 	__u32 mtu;
892 	int err;
893 
894 	if (!t->parms.collect_md &&
895 	    prepare_ip6gre_xmit_other(skb, dev, &fl6, &dsfield, &encap_limit))
896 		return -1;
897 
898 	err = gre_handle_offloads(skb, test_bit(IP_TUNNEL_CSUM_BIT,
899 						t->parms.o_flags));
900 	if (err)
901 		return err;
902 	err = __gre6_xmit(skb, dev, dsfield, &fl6, encap_limit, &mtu, skb->protocol);
903 
904 	return err;
905 }
906 
ip6gre_tunnel_xmit(struct sk_buff * skb,struct net_device * dev)907 static netdev_tx_t ip6gre_tunnel_xmit(struct sk_buff *skb,
908 	struct net_device *dev)
909 {
910 	struct ip6_tnl *t = netdev_priv(dev);
911 	__be16 payload_protocol;
912 	int ret;
913 
914 	if (!pskb_inet_may_pull(skb))
915 		goto tx_err;
916 
917 	if (!ip6_tnl_xmit_ctl(t, &t->parms.laddr, &t->parms.raddr))
918 		goto tx_err;
919 
920 	payload_protocol = skb_protocol(skb, true);
921 	switch (payload_protocol) {
922 	case htons(ETH_P_IP):
923 		ret = ip6gre_xmit_ipv4(skb, dev);
924 		break;
925 	case htons(ETH_P_IPV6):
926 		ret = ip6gre_xmit_ipv6(skb, dev);
927 		break;
928 	default:
929 		ret = ip6gre_xmit_other(skb, dev);
930 		break;
931 	}
932 
933 	if (ret < 0)
934 		goto tx_err;
935 
936 	return NETDEV_TX_OK;
937 
938 tx_err:
939 	if (!t->parms.collect_md || !IS_ERR(skb_tunnel_info_txcheck(skb)))
940 		DEV_STATS_INC(dev, tx_errors);
941 	DEV_STATS_INC(dev, tx_dropped);
942 	kfree_skb(skb);
943 	return NETDEV_TX_OK;
944 }
945 
ip6erspan_tunnel_xmit(struct sk_buff * skb,struct net_device * dev)946 static netdev_tx_t ip6erspan_tunnel_xmit(struct sk_buff *skb,
947 					 struct net_device *dev)
948 {
949 	struct ip_tunnel_info *tun_info = NULL;
950 	struct ip6_tnl *t = netdev_priv(dev);
951 	struct dst_entry *dst = skb_dst(skb);
952 	IP_TUNNEL_DECLARE_FLAGS(flags) = { };
953 	bool truncate = false;
954 	int encap_limit = -1;
955 	__u8 dsfield = false;
956 	struct flowi6 fl6;
957 	int err = -EINVAL;
958 	__be16 proto;
959 	__u32 mtu;
960 	int nhoff;
961 
962 	if (!pskb_inet_may_pull(skb))
963 		goto tx_err;
964 
965 	if (!ip6_tnl_xmit_ctl(t, &t->parms.laddr, &t->parms.raddr))
966 		goto tx_err;
967 
968 	if (gre_handle_offloads(skb, false))
969 		goto tx_err;
970 
971 	if (skb->len > dev->mtu + dev->hard_header_len) {
972 		if (pskb_trim(skb, dev->mtu + dev->hard_header_len))
973 			goto tx_err;
974 		truncate = true;
975 	}
976 
977 	nhoff = skb_network_offset(skb);
978 	if (skb->protocol == htons(ETH_P_IP) &&
979 	    (ntohs(ip_hdr(skb)->tot_len) > skb->len - nhoff))
980 		truncate = true;
981 
982 	if (skb->protocol == htons(ETH_P_IPV6)) {
983 		int thoff;
984 
985 		if (skb_transport_header_was_set(skb))
986 			thoff = skb_transport_offset(skb);
987 		else
988 			thoff = nhoff + sizeof(struct ipv6hdr);
989 		if (ntohs(ipv6_hdr(skb)->payload_len) > skb->len - thoff)
990 			truncate = true;
991 	}
992 
993 	if (skb_cow_head(skb, dev->needed_headroom ?: t->hlen))
994 		goto tx_err;
995 
996 	__clear_bit(IP_TUNNEL_KEY_BIT, t->parms.o_flags);
997 	IPCB(skb)->flags = 0;
998 
999 	/* For collect_md mode, derive fl6 from the tunnel key,
1000 	 * for native mode, call prepare_ip6gre_xmit_{ipv4,ipv6}.
1001 	 */
1002 	if (t->parms.collect_md) {
1003 		const struct ip_tunnel_key *key;
1004 		struct erspan_metadata *md;
1005 		__be32 tun_id;
1006 
1007 		tun_info = skb_tunnel_info_txcheck(skb);
1008 		if (IS_ERR(tun_info) ||
1009 		    unlikely(ip_tunnel_info_af(tun_info) != AF_INET6))
1010 			goto tx_err;
1011 
1012 		key = &tun_info->key;
1013 		memset(&fl6, 0, sizeof(fl6));
1014 		fl6.flowi6_proto = IPPROTO_GRE;
1015 		fl6.daddr = key->u.ipv6.dst;
1016 		fl6.flowlabel = key->label;
1017 		fl6.flowi6_uid = sock_net_uid(dev_net(dev), NULL);
1018 		fl6.fl6_gre_key = tunnel_id_to_key32(key->tun_id);
1019 
1020 		dsfield = key->tos;
1021 		if (!test_bit(IP_TUNNEL_ERSPAN_OPT_BIT,
1022 			      tun_info->key.tun_flags))
1023 			goto tx_err;
1024 		if (tun_info->options_len < sizeof(*md))
1025 			goto tx_err;
1026 		md = ip_tunnel_info_opts(tun_info);
1027 
1028 		tun_id = tunnel_id_to_key32(key->tun_id);
1029 		if (md->version == 1) {
1030 			erspan_build_header(skb,
1031 					    ntohl(tun_id),
1032 					    ntohl(md->u.index), truncate,
1033 					    false);
1034 			proto = htons(ETH_P_ERSPAN);
1035 		} else if (md->version == 2) {
1036 			erspan_build_header_v2(skb,
1037 					       ntohl(tun_id),
1038 					       md->u.md2.dir,
1039 					       get_hwid(&md->u.md2),
1040 					       truncate, false);
1041 			proto = htons(ETH_P_ERSPAN2);
1042 		} else {
1043 			goto tx_err;
1044 		}
1045 	} else {
1046 		switch (skb->protocol) {
1047 		case htons(ETH_P_IP):
1048 			memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
1049 			prepare_ip6gre_xmit_ipv4(skb, dev, &fl6,
1050 						 &dsfield, &encap_limit);
1051 			break;
1052 		case htons(ETH_P_IPV6):
1053 			if (ipv6_addr_equal(&t->parms.raddr, &ipv6_hdr(skb)->saddr))
1054 				goto tx_err;
1055 			if (prepare_ip6gre_xmit_ipv6(skb, dev, &fl6,
1056 						     &dsfield, &encap_limit))
1057 				goto tx_err;
1058 			break;
1059 		default:
1060 			memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6));
1061 			break;
1062 		}
1063 
1064 		if (t->parms.erspan_ver == 1) {
1065 			erspan_build_header(skb, ntohl(t->parms.o_key),
1066 					    t->parms.index,
1067 					    truncate, false);
1068 			proto = htons(ETH_P_ERSPAN);
1069 		} else if (t->parms.erspan_ver == 2) {
1070 			erspan_build_header_v2(skb, ntohl(t->parms.o_key),
1071 					       t->parms.dir,
1072 					       t->parms.hwid,
1073 					       truncate, false);
1074 			proto = htons(ETH_P_ERSPAN2);
1075 		} else {
1076 			goto tx_err;
1077 		}
1078 
1079 		fl6.daddr = t->parms.raddr;
1080 	}
1081 
1082 	/* Push GRE header. */
1083 	__set_bit(IP_TUNNEL_SEQ_BIT, flags);
1084 	gre_build_header(skb, 8, flags, proto, 0,
1085 			 htonl(atomic_fetch_inc(&t->o_seqno)));
1086 
1087 	/* TooBig packet may have updated dst->dev's mtu */
1088 	if (!t->parms.collect_md && dst && dst_mtu(dst) > dst->dev->mtu)
1089 		dst->ops->update_pmtu(dst, NULL, skb, dst->dev->mtu, false);
1090 
1091 	err = ip6_tnl_xmit(skb, dev, dsfield, &fl6, encap_limit, &mtu,
1092 			   NEXTHDR_GRE);
1093 	if (err != 0) {
1094 		/* XXX: send ICMP error even if DF is not set. */
1095 		if (err == -EMSGSIZE) {
1096 			if (skb->protocol == htons(ETH_P_IP))
1097 				icmp_ndo_send(skb, ICMP_DEST_UNREACH,
1098 					      ICMP_FRAG_NEEDED, htonl(mtu));
1099 			else
1100 				icmpv6_ndo_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
1101 		}
1102 
1103 		goto tx_err;
1104 	}
1105 	return NETDEV_TX_OK;
1106 
1107 tx_err:
1108 	if (!IS_ERR(tun_info))
1109 		DEV_STATS_INC(dev, tx_errors);
1110 	DEV_STATS_INC(dev, tx_dropped);
1111 	kfree_skb(skb);
1112 	return NETDEV_TX_OK;
1113 }
1114 
ip6gre_tnl_link_config_common(struct ip6_tnl * t)1115 static void ip6gre_tnl_link_config_common(struct ip6_tnl *t)
1116 {
1117 	struct net_device *dev = t->dev;
1118 	struct __ip6_tnl_parm *p = &t->parms;
1119 	struct flowi6 *fl6 = &t->fl.u.ip6;
1120 
1121 	if (dev->type != ARPHRD_ETHER) {
1122 		__dev_addr_set(dev, &p->laddr, sizeof(struct in6_addr));
1123 		memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr));
1124 	}
1125 
1126 	/* Set up flowi template */
1127 	fl6->saddr = p->laddr;
1128 	fl6->daddr = p->raddr;
1129 	fl6->flowi6_oif = p->link;
1130 	fl6->flowlabel = 0;
1131 	fl6->flowi6_proto = IPPROTO_GRE;
1132 	fl6->fl6_gre_key = t->parms.o_key;
1133 
1134 	if (!(p->flags&IP6_TNL_F_USE_ORIG_TCLASS))
1135 		fl6->flowlabel |= IPV6_TCLASS_MASK & p->flowinfo;
1136 	if (!(p->flags&IP6_TNL_F_USE_ORIG_FLOWLABEL))
1137 		fl6->flowlabel |= IPV6_FLOWLABEL_MASK & p->flowinfo;
1138 
1139 	p->flags &= ~(IP6_TNL_F_CAP_XMIT|IP6_TNL_F_CAP_RCV|IP6_TNL_F_CAP_PER_PACKET);
1140 	p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr);
1141 
1142 	if (p->flags&IP6_TNL_F_CAP_XMIT &&
1143 			p->flags&IP6_TNL_F_CAP_RCV && dev->type != ARPHRD_ETHER)
1144 		dev->flags |= IFF_POINTOPOINT;
1145 	else
1146 		dev->flags &= ~IFF_POINTOPOINT;
1147 }
1148 
ip6gre_tnl_link_config_route(struct ip6_tnl * t,int set_mtu,int t_hlen)1149 static void ip6gre_tnl_link_config_route(struct ip6_tnl *t, int set_mtu,
1150 					 int t_hlen)
1151 {
1152 	const struct __ip6_tnl_parm *p = &t->parms;
1153 	struct net_device *dev = t->dev;
1154 
1155 	if (p->flags & IP6_TNL_F_CAP_XMIT) {
1156 		int strict = (ipv6_addr_type(&p->raddr) &
1157 			      (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL));
1158 
1159 		struct rt6_info *rt = rt6_lookup(t->net,
1160 						 &p->raddr, &p->laddr,
1161 						 p->link, NULL, strict);
1162 
1163 		if (!rt)
1164 			return;
1165 
1166 		if (rt->dst.dev) {
1167 			unsigned short dst_len = rt->dst.dev->hard_header_len +
1168 						 t_hlen;
1169 
1170 			if (t->dev->header_ops)
1171 				dev->hard_header_len = dst_len;
1172 			else
1173 				dev->needed_headroom = dst_len;
1174 
1175 			if (set_mtu) {
1176 				int mtu = rt->dst.dev->mtu - t_hlen;
1177 
1178 				if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1179 					mtu -= 8;
1180 				if (dev->type == ARPHRD_ETHER)
1181 					mtu -= ETH_HLEN;
1182 
1183 				if (mtu < IPV6_MIN_MTU)
1184 					mtu = IPV6_MIN_MTU;
1185 				WRITE_ONCE(dev->mtu, mtu);
1186 			}
1187 		}
1188 		ip6_rt_put(rt);
1189 	}
1190 }
1191 
ip6gre_calc_hlen(struct ip6_tnl * tunnel)1192 static int ip6gre_calc_hlen(struct ip6_tnl *tunnel)
1193 {
1194 	int t_hlen;
1195 
1196 	tunnel->tun_hlen = gre_calc_hlen(tunnel->parms.o_flags);
1197 	tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen;
1198 
1199 	t_hlen = tunnel->hlen + sizeof(struct ipv6hdr);
1200 
1201 	if (tunnel->dev->header_ops)
1202 		tunnel->dev->hard_header_len = LL_MAX_HEADER + t_hlen;
1203 	else
1204 		tunnel->dev->needed_headroom = LL_MAX_HEADER + t_hlen;
1205 
1206 	return t_hlen;
1207 }
1208 
ip6gre_tnl_link_config(struct ip6_tnl * t,int set_mtu)1209 static void ip6gre_tnl_link_config(struct ip6_tnl *t, int set_mtu)
1210 {
1211 	ip6gre_tnl_link_config_common(t);
1212 	ip6gre_tnl_link_config_route(t, set_mtu, ip6gre_calc_hlen(t));
1213 }
1214 
ip6gre_tnl_copy_tnl_parm(struct ip6_tnl * t,const struct __ip6_tnl_parm * p)1215 static void ip6gre_tnl_copy_tnl_parm(struct ip6_tnl *t,
1216 				     const struct __ip6_tnl_parm *p)
1217 {
1218 	t->parms.laddr = p->laddr;
1219 	t->parms.raddr = p->raddr;
1220 	t->parms.flags = p->flags;
1221 	t->parms.hop_limit = p->hop_limit;
1222 	t->parms.encap_limit = p->encap_limit;
1223 	t->parms.flowinfo = p->flowinfo;
1224 	t->parms.link = p->link;
1225 	t->parms.proto = p->proto;
1226 	t->parms.i_key = p->i_key;
1227 	t->parms.o_key = p->o_key;
1228 	ip_tunnel_flags_copy(t->parms.i_flags, p->i_flags);
1229 	ip_tunnel_flags_copy(t->parms.o_flags, p->o_flags);
1230 	t->parms.fwmark = p->fwmark;
1231 	t->parms.erspan_ver = p->erspan_ver;
1232 	t->parms.index = p->index;
1233 	t->parms.dir = p->dir;
1234 	t->parms.hwid = p->hwid;
1235 	dst_cache_reset(&t->dst_cache);
1236 }
1237 
ip6gre_tnl_change(struct ip6_tnl * t,const struct __ip6_tnl_parm * p,int set_mtu)1238 static int ip6gre_tnl_change(struct ip6_tnl *t, const struct __ip6_tnl_parm *p,
1239 			     int set_mtu)
1240 {
1241 	ip6gre_tnl_copy_tnl_parm(t, p);
1242 	ip6gre_tnl_link_config(t, set_mtu);
1243 	return 0;
1244 }
1245 
ip6gre_tnl_parm_from_user(struct __ip6_tnl_parm * p,const struct ip6_tnl_parm2 * u)1246 static void ip6gre_tnl_parm_from_user(struct __ip6_tnl_parm *p,
1247 	const struct ip6_tnl_parm2 *u)
1248 {
1249 	p->laddr = u->laddr;
1250 	p->raddr = u->raddr;
1251 	p->flags = u->flags;
1252 	p->hop_limit = u->hop_limit;
1253 	p->encap_limit = u->encap_limit;
1254 	p->flowinfo = u->flowinfo;
1255 	p->link = u->link;
1256 	p->i_key = u->i_key;
1257 	p->o_key = u->o_key;
1258 	gre_flags_to_tnl_flags(p->i_flags, u->i_flags);
1259 	gre_flags_to_tnl_flags(p->o_flags, u->o_flags);
1260 	memcpy(p->name, u->name, sizeof(u->name));
1261 }
1262 
ip6gre_tnl_parm_to_user(struct ip6_tnl_parm2 * u,const struct __ip6_tnl_parm * p)1263 static void ip6gre_tnl_parm_to_user(struct ip6_tnl_parm2 *u,
1264 	const struct __ip6_tnl_parm *p)
1265 {
1266 	u->proto = IPPROTO_GRE;
1267 	u->laddr = p->laddr;
1268 	u->raddr = p->raddr;
1269 	u->flags = p->flags;
1270 	u->hop_limit = p->hop_limit;
1271 	u->encap_limit = p->encap_limit;
1272 	u->flowinfo = p->flowinfo;
1273 	u->link = p->link;
1274 	u->i_key = p->i_key;
1275 	u->o_key = p->o_key;
1276 	u->i_flags = gre_tnl_flags_to_gre_flags(p->i_flags);
1277 	u->o_flags = gre_tnl_flags_to_gre_flags(p->o_flags);
1278 	memcpy(u->name, p->name, sizeof(u->name));
1279 }
1280 
ip6gre_tunnel_siocdevprivate(struct net_device * dev,struct ifreq * ifr,void __user * data,int cmd)1281 static int ip6gre_tunnel_siocdevprivate(struct net_device *dev,
1282 					struct ifreq *ifr, void __user *data,
1283 					int cmd)
1284 {
1285 	int err = 0;
1286 	struct ip6_tnl_parm2 p;
1287 	struct __ip6_tnl_parm p1;
1288 	struct ip6_tnl *t = netdev_priv(dev);
1289 	struct net *net = t->net;
1290 	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
1291 
1292 	memset(&p1, 0, sizeof(p1));
1293 
1294 	switch (cmd) {
1295 	case SIOCGETTUNNEL:
1296 		if (dev == ign->fb_tunnel_dev) {
1297 			if (copy_from_user(&p, data, sizeof(p))) {
1298 				err = -EFAULT;
1299 				break;
1300 			}
1301 			ip6gre_tnl_parm_from_user(&p1, &p);
1302 			t = ip6gre_tunnel_locate(net, &p1, 0);
1303 			if (!t)
1304 				t = netdev_priv(dev);
1305 		}
1306 		memset(&p, 0, sizeof(p));
1307 		ip6gre_tnl_parm_to_user(&p, &t->parms);
1308 		if (copy_to_user(data, &p, sizeof(p)))
1309 			err = -EFAULT;
1310 		break;
1311 
1312 	case SIOCADDTUNNEL:
1313 	case SIOCCHGTUNNEL:
1314 		err = -EPERM;
1315 		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1316 			goto done;
1317 
1318 		err = -EFAULT;
1319 		if (copy_from_user(&p, data, sizeof(p)))
1320 			goto done;
1321 
1322 		err = -EINVAL;
1323 		if ((p.i_flags|p.o_flags)&(GRE_VERSION|GRE_ROUTING))
1324 			goto done;
1325 
1326 		if (!(p.i_flags&GRE_KEY))
1327 			p.i_key = 0;
1328 		if (!(p.o_flags&GRE_KEY))
1329 			p.o_key = 0;
1330 
1331 		ip6gre_tnl_parm_from_user(&p1, &p);
1332 		t = ip6gre_tunnel_locate(net, &p1, cmd == SIOCADDTUNNEL);
1333 
1334 		if (dev != ign->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) {
1335 			if (t) {
1336 				if (t->dev != dev) {
1337 					err = -EEXIST;
1338 					break;
1339 				}
1340 			} else {
1341 				t = netdev_priv(dev);
1342 
1343 				ip6gre_tunnel_unlink(ign, t);
1344 				synchronize_net();
1345 				ip6gre_tnl_change(t, &p1, 1);
1346 				ip6gre_tunnel_link(ign, t);
1347 				netdev_state_change(dev);
1348 			}
1349 		}
1350 
1351 		if (t) {
1352 			err = 0;
1353 
1354 			memset(&p, 0, sizeof(p));
1355 			ip6gre_tnl_parm_to_user(&p, &t->parms);
1356 			if (copy_to_user(data, &p, sizeof(p)))
1357 				err = -EFAULT;
1358 		} else
1359 			err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
1360 		break;
1361 
1362 	case SIOCDELTUNNEL:
1363 		err = -EPERM;
1364 		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1365 			goto done;
1366 
1367 		if (dev == ign->fb_tunnel_dev) {
1368 			err = -EFAULT;
1369 			if (copy_from_user(&p, data, sizeof(p)))
1370 				goto done;
1371 			err = -ENOENT;
1372 			ip6gre_tnl_parm_from_user(&p1, &p);
1373 			t = ip6gre_tunnel_locate(net, &p1, 0);
1374 			if (!t)
1375 				goto done;
1376 			err = -EPERM;
1377 			if (t == netdev_priv(ign->fb_tunnel_dev))
1378 				goto done;
1379 			dev = t->dev;
1380 		}
1381 		unregister_netdevice(dev);
1382 		err = 0;
1383 		break;
1384 
1385 	default:
1386 		err = -EINVAL;
1387 	}
1388 
1389 done:
1390 	return err;
1391 }
1392 
ip6gre_header(struct sk_buff * skb,struct net_device * dev,unsigned short type,const void * daddr,const void * saddr,unsigned int len)1393 static int ip6gre_header(struct sk_buff *skb, struct net_device *dev,
1394 			 unsigned short type, const void *daddr,
1395 			 const void *saddr, unsigned int len)
1396 {
1397 	struct ip6_tnl *t = netdev_priv(dev);
1398 	struct ipv6hdr *ipv6h;
1399 	__be16 *p;
1400 
1401 	ipv6h = skb_push(skb, t->hlen + sizeof(*ipv6h));
1402 	ip6_flow_hdr(ipv6h, 0, ip6_make_flowlabel(dev_net(dev), skb,
1403 						  t->fl.u.ip6.flowlabel,
1404 						  true, &t->fl.u.ip6));
1405 	ipv6h->hop_limit = t->parms.hop_limit;
1406 	ipv6h->nexthdr = NEXTHDR_GRE;
1407 	ipv6h->saddr = t->parms.laddr;
1408 	ipv6h->daddr = t->parms.raddr;
1409 
1410 	p = (__be16 *)(ipv6h + 1);
1411 	p[0] = ip_tunnel_flags_to_be16(t->parms.o_flags);
1412 	p[1] = htons(type);
1413 
1414 	/*
1415 	 *	Set the source hardware address.
1416 	 */
1417 
1418 	if (saddr)
1419 		memcpy(&ipv6h->saddr, saddr, sizeof(struct in6_addr));
1420 	if (daddr)
1421 		memcpy(&ipv6h->daddr, daddr, sizeof(struct in6_addr));
1422 	if (!ipv6_addr_any(&ipv6h->daddr))
1423 		return t->hlen;
1424 
1425 	return -t->hlen;
1426 }
1427 
1428 static const struct header_ops ip6gre_header_ops = {
1429 	.create	= ip6gre_header,
1430 };
1431 
1432 static const struct net_device_ops ip6gre_netdev_ops = {
1433 	.ndo_init		= ip6gre_tunnel_init,
1434 	.ndo_uninit		= ip6gre_tunnel_uninit,
1435 	.ndo_start_xmit		= ip6gre_tunnel_xmit,
1436 	.ndo_siocdevprivate	= ip6gre_tunnel_siocdevprivate,
1437 	.ndo_change_mtu		= ip6_tnl_change_mtu,
1438 	.ndo_get_iflink		= ip6_tnl_get_iflink,
1439 };
1440 
ip6gre_dev_free(struct net_device * dev)1441 static void ip6gre_dev_free(struct net_device *dev)
1442 {
1443 	struct ip6_tnl *t = netdev_priv(dev);
1444 
1445 	gro_cells_destroy(&t->gro_cells);
1446 	dst_cache_destroy(&t->dst_cache);
1447 }
1448 
ip6gre_tunnel_setup(struct net_device * dev)1449 static void ip6gre_tunnel_setup(struct net_device *dev)
1450 {
1451 	dev->netdev_ops = &ip6gre_netdev_ops;
1452 	dev->needs_free_netdev = true;
1453 	dev->priv_destructor = ip6gre_dev_free;
1454 
1455 	dev->pcpu_stat_type = NETDEV_PCPU_STAT_TSTATS;
1456 	dev->type = ARPHRD_IP6GRE;
1457 
1458 	dev->flags |= IFF_NOARP;
1459 	dev->addr_len = sizeof(struct in6_addr);
1460 	netif_keep_dst(dev);
1461 	/* This perm addr will be used as interface identifier by IPv6 */
1462 	dev->addr_assign_type = NET_ADDR_RANDOM;
1463 	eth_random_addr(dev->perm_addr);
1464 }
1465 
1466 #define GRE6_FEATURES (NETIF_F_SG |		\
1467 		       NETIF_F_FRAGLIST |	\
1468 		       NETIF_F_HIGHDMA |	\
1469 		       NETIF_F_HW_CSUM)
1470 
ip6gre_tnl_init_features(struct net_device * dev)1471 static void ip6gre_tnl_init_features(struct net_device *dev)
1472 {
1473 	struct ip6_tnl *nt = netdev_priv(dev);
1474 
1475 	dev->features		|= GRE6_FEATURES;
1476 	dev->hw_features	|= GRE6_FEATURES;
1477 
1478 	/* TCP offload with GRE SEQ is not supported, nor can we support 2
1479 	 * levels of outer headers requiring an update.
1480 	 */
1481 	if (test_bit(IP_TUNNEL_SEQ_BIT, nt->parms.o_flags))
1482 		return;
1483 	if (test_bit(IP_TUNNEL_CSUM_BIT, nt->parms.o_flags) &&
1484 	    nt->encap.type != TUNNEL_ENCAP_NONE)
1485 		return;
1486 
1487 	dev->features |= NETIF_F_GSO_SOFTWARE;
1488 	dev->hw_features |= NETIF_F_GSO_SOFTWARE;
1489 
1490 	dev->lltx = true;
1491 }
1492 
ip6gre_tunnel_init_common(struct net_device * dev)1493 static int ip6gre_tunnel_init_common(struct net_device *dev)
1494 {
1495 	struct ip6_tnl *tunnel;
1496 	int ret;
1497 	int t_hlen;
1498 
1499 	tunnel = netdev_priv(dev);
1500 
1501 	tunnel->dev = dev;
1502 	strcpy(tunnel->parms.name, dev->name);
1503 
1504 	ret = dst_cache_init(&tunnel->dst_cache, GFP_KERNEL);
1505 	if (ret)
1506 		return ret;
1507 
1508 	ret = gro_cells_init(&tunnel->gro_cells, dev);
1509 	if (ret)
1510 		goto cleanup_dst_cache_init;
1511 
1512 	t_hlen = ip6gre_calc_hlen(tunnel);
1513 	dev->mtu = ETH_DATA_LEN - t_hlen;
1514 	if (dev->type == ARPHRD_ETHER)
1515 		dev->mtu -= ETH_HLEN;
1516 	if (!(tunnel->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1517 		dev->mtu -= 8;
1518 
1519 	if (tunnel->parms.collect_md) {
1520 		netif_keep_dst(dev);
1521 	}
1522 	ip6gre_tnl_init_features(dev);
1523 
1524 	netdev_hold(dev, &tunnel->dev_tracker, GFP_KERNEL);
1525 	netdev_lockdep_set_classes(dev);
1526 	return 0;
1527 
1528 cleanup_dst_cache_init:
1529 	dst_cache_destroy(&tunnel->dst_cache);
1530 	return ret;
1531 }
1532 
ip6gre_tunnel_init(struct net_device * dev)1533 static int ip6gre_tunnel_init(struct net_device *dev)
1534 {
1535 	struct ip6_tnl *tunnel;
1536 	int ret;
1537 
1538 	ret = ip6gre_tunnel_init_common(dev);
1539 	if (ret)
1540 		return ret;
1541 
1542 	tunnel = netdev_priv(dev);
1543 
1544 	if (tunnel->parms.collect_md)
1545 		return 0;
1546 
1547 	__dev_addr_set(dev, &tunnel->parms.laddr, sizeof(struct in6_addr));
1548 	memcpy(dev->broadcast, &tunnel->parms.raddr, sizeof(struct in6_addr));
1549 
1550 	if (ipv6_addr_any(&tunnel->parms.raddr))
1551 		dev->header_ops = &ip6gre_header_ops;
1552 
1553 	return 0;
1554 }
1555 
ip6gre_fb_tunnel_init(struct net_device * dev)1556 static void ip6gre_fb_tunnel_init(struct net_device *dev)
1557 {
1558 	struct ip6_tnl *tunnel = netdev_priv(dev);
1559 
1560 	tunnel->dev = dev;
1561 	tunnel->net = dev_net(dev);
1562 	strcpy(tunnel->parms.name, dev->name);
1563 
1564 	tunnel->hlen		= sizeof(struct ipv6hdr) + 4;
1565 }
1566 
1567 static struct inet6_protocol ip6gre_protocol __read_mostly = {
1568 	.handler     = gre_rcv,
1569 	.err_handler = ip6gre_err,
1570 	.flags       = INET6_PROTO_FINAL,
1571 };
1572 
ip6gre_destroy_tunnels(struct net * net,struct list_head * head)1573 static void ip6gre_destroy_tunnels(struct net *net, struct list_head *head)
1574 {
1575 	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
1576 	struct net_device *dev, *aux;
1577 	int prio;
1578 
1579 	for_each_netdev_safe(net, dev, aux)
1580 		if (dev->rtnl_link_ops == &ip6gre_link_ops ||
1581 		    dev->rtnl_link_ops == &ip6gre_tap_ops ||
1582 		    dev->rtnl_link_ops == &ip6erspan_tap_ops)
1583 			unregister_netdevice_queue(dev, head);
1584 
1585 	for (prio = 0; prio < 4; prio++) {
1586 		int h;
1587 		for (h = 0; h < IP6_GRE_HASH_SIZE; h++) {
1588 			struct ip6_tnl *t;
1589 
1590 			t = rtnl_dereference(ign->tunnels[prio][h]);
1591 
1592 			while (t) {
1593 				/* If dev is in the same netns, it has already
1594 				 * been added to the list by the previous loop.
1595 				 */
1596 				if (!net_eq(dev_net(t->dev), net))
1597 					unregister_netdevice_queue(t->dev,
1598 								   head);
1599 				t = rtnl_dereference(t->next);
1600 			}
1601 		}
1602 	}
1603 }
1604 
ip6gre_init_net(struct net * net)1605 static int __net_init ip6gre_init_net(struct net *net)
1606 {
1607 	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
1608 	struct net_device *ndev;
1609 	int err;
1610 
1611 	if (!net_has_fallback_tunnels(net))
1612 		return 0;
1613 	ndev = alloc_netdev(sizeof(struct ip6_tnl), "ip6gre0",
1614 			    NET_NAME_UNKNOWN, ip6gre_tunnel_setup);
1615 	if (!ndev) {
1616 		err = -ENOMEM;
1617 		goto err_alloc_dev;
1618 	}
1619 	ign->fb_tunnel_dev = ndev;
1620 	dev_net_set(ign->fb_tunnel_dev, net);
1621 	/* FB netdevice is special: we have one, and only one per netns.
1622 	 * Allowing to move it to another netns is clearly unsafe.
1623 	 */
1624 	ign->fb_tunnel_dev->netns_immutable = true;
1625 
1626 	ip6gre_fb_tunnel_init(ign->fb_tunnel_dev);
1627 	ign->fb_tunnel_dev->rtnl_link_ops = &ip6gre_link_ops;
1628 
1629 	err = register_netdev(ign->fb_tunnel_dev);
1630 	if (err)
1631 		goto err_reg_dev;
1632 
1633 	rcu_assign_pointer(ign->tunnels_wc[0],
1634 			   netdev_priv(ign->fb_tunnel_dev));
1635 	return 0;
1636 
1637 err_reg_dev:
1638 	free_netdev(ndev);
1639 err_alloc_dev:
1640 	return err;
1641 }
1642 
ip6gre_exit_batch_rtnl(struct list_head * net_list,struct list_head * dev_to_kill)1643 static void __net_exit ip6gre_exit_batch_rtnl(struct list_head *net_list,
1644 					      struct list_head *dev_to_kill)
1645 {
1646 	struct net *net;
1647 
1648 	ASSERT_RTNL();
1649 	list_for_each_entry(net, net_list, exit_list)
1650 		ip6gre_destroy_tunnels(net, dev_to_kill);
1651 }
1652 
1653 static struct pernet_operations ip6gre_net_ops = {
1654 	.init = ip6gre_init_net,
1655 	.exit_batch_rtnl = ip6gre_exit_batch_rtnl,
1656 	.id   = &ip6gre_net_id,
1657 	.size = sizeof(struct ip6gre_net),
1658 };
1659 
ip6gre_tunnel_validate(struct nlattr * tb[],struct nlattr * data[],struct netlink_ext_ack * extack)1660 static int ip6gre_tunnel_validate(struct nlattr *tb[], struct nlattr *data[],
1661 				  struct netlink_ext_ack *extack)
1662 {
1663 	__be16 flags;
1664 
1665 	if (!data)
1666 		return 0;
1667 
1668 	flags = 0;
1669 	if (data[IFLA_GRE_IFLAGS])
1670 		flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]);
1671 	if (data[IFLA_GRE_OFLAGS])
1672 		flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]);
1673 	if (flags & (GRE_VERSION|GRE_ROUTING))
1674 		return -EINVAL;
1675 
1676 	return 0;
1677 }
1678 
ip6gre_tap_validate(struct nlattr * tb[],struct nlattr * data[],struct netlink_ext_ack * extack)1679 static int ip6gre_tap_validate(struct nlattr *tb[], struct nlattr *data[],
1680 			       struct netlink_ext_ack *extack)
1681 {
1682 	struct in6_addr daddr;
1683 
1684 	if (tb[IFLA_ADDRESS]) {
1685 		if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
1686 			return -EINVAL;
1687 		if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
1688 			return -EADDRNOTAVAIL;
1689 	}
1690 
1691 	if (!data)
1692 		goto out;
1693 
1694 	if (data[IFLA_GRE_REMOTE]) {
1695 		daddr = nla_get_in6_addr(data[IFLA_GRE_REMOTE]);
1696 		if (ipv6_addr_any(&daddr))
1697 			return -EINVAL;
1698 	}
1699 
1700 out:
1701 	return ip6gre_tunnel_validate(tb, data, extack);
1702 }
1703 
ip6erspan_tap_validate(struct nlattr * tb[],struct nlattr * data[],struct netlink_ext_ack * extack)1704 static int ip6erspan_tap_validate(struct nlattr *tb[], struct nlattr *data[],
1705 				  struct netlink_ext_ack *extack)
1706 {
1707 	__be16 flags = 0;
1708 	int ret, ver = 0;
1709 
1710 	if (!data)
1711 		return 0;
1712 
1713 	ret = ip6gre_tap_validate(tb, data, extack);
1714 	if (ret)
1715 		return ret;
1716 
1717 	/* ERSPAN should only have GRE sequence and key flag */
1718 	if (data[IFLA_GRE_OFLAGS])
1719 		flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]);
1720 	if (data[IFLA_GRE_IFLAGS])
1721 		flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]);
1722 	if (!data[IFLA_GRE_COLLECT_METADATA] &&
1723 	    flags != (GRE_SEQ | GRE_KEY))
1724 		return -EINVAL;
1725 
1726 	/* ERSPAN Session ID only has 10-bit. Since we reuse
1727 	 * 32-bit key field as ID, check it's range.
1728 	 */
1729 	if (data[IFLA_GRE_IKEY] &&
1730 	    (ntohl(nla_get_be32(data[IFLA_GRE_IKEY])) & ~ID_MASK))
1731 		return -EINVAL;
1732 
1733 	if (data[IFLA_GRE_OKEY] &&
1734 	    (ntohl(nla_get_be32(data[IFLA_GRE_OKEY])) & ~ID_MASK))
1735 		return -EINVAL;
1736 
1737 	if (data[IFLA_GRE_ERSPAN_VER]) {
1738 		ver = nla_get_u8(data[IFLA_GRE_ERSPAN_VER]);
1739 		if (ver != 1 && ver != 2)
1740 			return -EINVAL;
1741 	}
1742 
1743 	if (ver == 1) {
1744 		if (data[IFLA_GRE_ERSPAN_INDEX]) {
1745 			u32 index = nla_get_u32(data[IFLA_GRE_ERSPAN_INDEX]);
1746 
1747 			if (index & ~INDEX_MASK)
1748 				return -EINVAL;
1749 		}
1750 	} else if (ver == 2) {
1751 		if (data[IFLA_GRE_ERSPAN_DIR]) {
1752 			u16 dir = nla_get_u8(data[IFLA_GRE_ERSPAN_DIR]);
1753 
1754 			if (dir & ~(DIR_MASK >> DIR_OFFSET))
1755 				return -EINVAL;
1756 		}
1757 
1758 		if (data[IFLA_GRE_ERSPAN_HWID]) {
1759 			u16 hwid = nla_get_u16(data[IFLA_GRE_ERSPAN_HWID]);
1760 
1761 			if (hwid & ~(HWID_MASK >> HWID_OFFSET))
1762 				return -EINVAL;
1763 		}
1764 	}
1765 
1766 	return 0;
1767 }
1768 
ip6erspan_set_version(struct nlattr * data[],struct __ip6_tnl_parm * parms)1769 static void ip6erspan_set_version(struct nlattr *data[],
1770 				  struct __ip6_tnl_parm *parms)
1771 {
1772 	if (!data)
1773 		return;
1774 
1775 	parms->erspan_ver = 1;
1776 	if (data[IFLA_GRE_ERSPAN_VER])
1777 		parms->erspan_ver = nla_get_u8(data[IFLA_GRE_ERSPAN_VER]);
1778 
1779 	if (parms->erspan_ver == 1) {
1780 		if (data[IFLA_GRE_ERSPAN_INDEX])
1781 			parms->index = nla_get_u32(data[IFLA_GRE_ERSPAN_INDEX]);
1782 	} else if (parms->erspan_ver == 2) {
1783 		if (data[IFLA_GRE_ERSPAN_DIR])
1784 			parms->dir = nla_get_u8(data[IFLA_GRE_ERSPAN_DIR]);
1785 		if (data[IFLA_GRE_ERSPAN_HWID])
1786 			parms->hwid = nla_get_u16(data[IFLA_GRE_ERSPAN_HWID]);
1787 	}
1788 }
1789 
ip6gre_netlink_parms(struct nlattr * data[],struct __ip6_tnl_parm * parms)1790 static void ip6gre_netlink_parms(struct nlattr *data[],
1791 				struct __ip6_tnl_parm *parms)
1792 {
1793 	memset(parms, 0, sizeof(*parms));
1794 
1795 	if (!data)
1796 		return;
1797 
1798 	if (data[IFLA_GRE_LINK])
1799 		parms->link = nla_get_u32(data[IFLA_GRE_LINK]);
1800 
1801 	if (data[IFLA_GRE_IFLAGS])
1802 		gre_flags_to_tnl_flags(parms->i_flags,
1803 				       nla_get_be16(data[IFLA_GRE_IFLAGS]));
1804 
1805 	if (data[IFLA_GRE_OFLAGS])
1806 		gre_flags_to_tnl_flags(parms->o_flags,
1807 				       nla_get_be16(data[IFLA_GRE_OFLAGS]));
1808 
1809 	if (data[IFLA_GRE_IKEY])
1810 		parms->i_key = nla_get_be32(data[IFLA_GRE_IKEY]);
1811 
1812 	if (data[IFLA_GRE_OKEY])
1813 		parms->o_key = nla_get_be32(data[IFLA_GRE_OKEY]);
1814 
1815 	if (data[IFLA_GRE_LOCAL])
1816 		parms->laddr = nla_get_in6_addr(data[IFLA_GRE_LOCAL]);
1817 
1818 	if (data[IFLA_GRE_REMOTE])
1819 		parms->raddr = nla_get_in6_addr(data[IFLA_GRE_REMOTE]);
1820 
1821 	if (data[IFLA_GRE_TTL])
1822 		parms->hop_limit = nla_get_u8(data[IFLA_GRE_TTL]);
1823 
1824 	if (data[IFLA_GRE_ENCAP_LIMIT])
1825 		parms->encap_limit = nla_get_u8(data[IFLA_GRE_ENCAP_LIMIT]);
1826 
1827 	if (data[IFLA_GRE_FLOWINFO])
1828 		parms->flowinfo = nla_get_be32(data[IFLA_GRE_FLOWINFO]);
1829 
1830 	if (data[IFLA_GRE_FLAGS])
1831 		parms->flags = nla_get_u32(data[IFLA_GRE_FLAGS]);
1832 
1833 	if (data[IFLA_GRE_FWMARK])
1834 		parms->fwmark = nla_get_u32(data[IFLA_GRE_FWMARK]);
1835 
1836 	if (data[IFLA_GRE_COLLECT_METADATA])
1837 		parms->collect_md = true;
1838 }
1839 
ip6gre_tap_init(struct net_device * dev)1840 static int ip6gre_tap_init(struct net_device *dev)
1841 {
1842 	int ret;
1843 
1844 	ret = ip6gre_tunnel_init_common(dev);
1845 	if (ret)
1846 		return ret;
1847 
1848 	dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1849 
1850 	return 0;
1851 }
1852 
1853 static const struct net_device_ops ip6gre_tap_netdev_ops = {
1854 	.ndo_init = ip6gre_tap_init,
1855 	.ndo_uninit = ip6gre_tunnel_uninit,
1856 	.ndo_start_xmit = ip6gre_tunnel_xmit,
1857 	.ndo_set_mac_address = eth_mac_addr,
1858 	.ndo_validate_addr = eth_validate_addr,
1859 	.ndo_change_mtu = ip6_tnl_change_mtu,
1860 	.ndo_get_iflink = ip6_tnl_get_iflink,
1861 };
1862 
ip6erspan_calc_hlen(struct ip6_tnl * tunnel)1863 static int ip6erspan_calc_hlen(struct ip6_tnl *tunnel)
1864 {
1865 	int t_hlen;
1866 
1867 	tunnel->tun_hlen = 8;
1868 	tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen +
1869 		       erspan_hdr_len(tunnel->parms.erspan_ver);
1870 
1871 	t_hlen = tunnel->hlen + sizeof(struct ipv6hdr);
1872 	tunnel->dev->needed_headroom = LL_MAX_HEADER + t_hlen;
1873 	return t_hlen;
1874 }
1875 
ip6erspan_tap_init(struct net_device * dev)1876 static int ip6erspan_tap_init(struct net_device *dev)
1877 {
1878 	struct ip6_tnl *tunnel;
1879 	int t_hlen;
1880 	int ret;
1881 
1882 	tunnel = netdev_priv(dev);
1883 
1884 	tunnel->dev = dev;
1885 	strcpy(tunnel->parms.name, dev->name);
1886 
1887 	ret = dst_cache_init(&tunnel->dst_cache, GFP_KERNEL);
1888 	if (ret)
1889 		return ret;
1890 
1891 	ret = gro_cells_init(&tunnel->gro_cells, dev);
1892 	if (ret)
1893 		goto cleanup_dst_cache_init;
1894 
1895 	t_hlen = ip6erspan_calc_hlen(tunnel);
1896 	dev->mtu = ETH_DATA_LEN - t_hlen;
1897 	if (dev->type == ARPHRD_ETHER)
1898 		dev->mtu -= ETH_HLEN;
1899 	if (!(tunnel->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1900 		dev->mtu -= 8;
1901 
1902 	dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1903 	ip6erspan_tnl_link_config(tunnel, 1);
1904 
1905 	netdev_hold(dev, &tunnel->dev_tracker, GFP_KERNEL);
1906 	netdev_lockdep_set_classes(dev);
1907 	return 0;
1908 
1909 cleanup_dst_cache_init:
1910 	dst_cache_destroy(&tunnel->dst_cache);
1911 	return ret;
1912 }
1913 
1914 static const struct net_device_ops ip6erspan_netdev_ops = {
1915 	.ndo_init =		ip6erspan_tap_init,
1916 	.ndo_uninit =		ip6erspan_tunnel_uninit,
1917 	.ndo_start_xmit =	ip6erspan_tunnel_xmit,
1918 	.ndo_set_mac_address =	eth_mac_addr,
1919 	.ndo_validate_addr =	eth_validate_addr,
1920 	.ndo_change_mtu =	ip6_tnl_change_mtu,
1921 	.ndo_get_iflink =	ip6_tnl_get_iflink,
1922 };
1923 
ip6gre_tap_setup(struct net_device * dev)1924 static void ip6gre_tap_setup(struct net_device *dev)
1925 {
1926 
1927 	ether_setup(dev);
1928 
1929 	dev->max_mtu = 0;
1930 	dev->netdev_ops = &ip6gre_tap_netdev_ops;
1931 	dev->needs_free_netdev = true;
1932 	dev->priv_destructor = ip6gre_dev_free;
1933 
1934 	dev->pcpu_stat_type = NETDEV_PCPU_STAT_TSTATS;
1935 	dev->priv_flags &= ~IFF_TX_SKB_SHARING;
1936 	dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1937 	netif_keep_dst(dev);
1938 }
1939 
ip6gre_netlink_encap_parms(struct nlattr * data[],struct ip_tunnel_encap * ipencap)1940 static bool ip6gre_netlink_encap_parms(struct nlattr *data[],
1941 				       struct ip_tunnel_encap *ipencap)
1942 {
1943 	bool ret = false;
1944 
1945 	memset(ipencap, 0, sizeof(*ipencap));
1946 
1947 	if (!data)
1948 		return ret;
1949 
1950 	if (data[IFLA_GRE_ENCAP_TYPE]) {
1951 		ret = true;
1952 		ipencap->type = nla_get_u16(data[IFLA_GRE_ENCAP_TYPE]);
1953 	}
1954 
1955 	if (data[IFLA_GRE_ENCAP_FLAGS]) {
1956 		ret = true;
1957 		ipencap->flags = nla_get_u16(data[IFLA_GRE_ENCAP_FLAGS]);
1958 	}
1959 
1960 	if (data[IFLA_GRE_ENCAP_SPORT]) {
1961 		ret = true;
1962 		ipencap->sport = nla_get_be16(data[IFLA_GRE_ENCAP_SPORT]);
1963 	}
1964 
1965 	if (data[IFLA_GRE_ENCAP_DPORT]) {
1966 		ret = true;
1967 		ipencap->dport = nla_get_be16(data[IFLA_GRE_ENCAP_DPORT]);
1968 	}
1969 
1970 	return ret;
1971 }
1972 
ip6gre_newlink_common(struct net * link_net,struct net_device * dev,struct nlattr * tb[],struct nlattr * data[],struct netlink_ext_ack * extack)1973 static int ip6gre_newlink_common(struct net *link_net, struct net_device *dev,
1974 				 struct nlattr *tb[], struct nlattr *data[],
1975 				 struct netlink_ext_ack *extack)
1976 {
1977 	struct ip6_tnl *nt;
1978 	struct ip_tunnel_encap ipencap;
1979 	int err;
1980 
1981 	nt = netdev_priv(dev);
1982 
1983 	if (ip6gre_netlink_encap_parms(data, &ipencap)) {
1984 		int err = ip6_tnl_encap_setup(nt, &ipencap);
1985 
1986 		if (err < 0)
1987 			return err;
1988 	}
1989 
1990 	if (dev->type == ARPHRD_ETHER && !tb[IFLA_ADDRESS])
1991 		eth_hw_addr_random(dev);
1992 
1993 	nt->dev = dev;
1994 	nt->net = link_net;
1995 
1996 	err = register_netdevice(dev);
1997 	if (err)
1998 		goto out;
1999 
2000 	if (tb[IFLA_MTU])
2001 		ip6_tnl_change_mtu(dev, nla_get_u32(tb[IFLA_MTU]));
2002 
2003 out:
2004 	return err;
2005 }
2006 
ip6gre_newlink(struct net_device * dev,struct rtnl_newlink_params * params,struct netlink_ext_ack * extack)2007 static int ip6gre_newlink(struct net_device *dev,
2008 			  struct rtnl_newlink_params *params,
2009 			  struct netlink_ext_ack *extack)
2010 {
2011 	struct net *net = params->link_net ? : dev_net(dev);
2012 	struct ip6_tnl *nt = netdev_priv(dev);
2013 	struct nlattr **data = params->data;
2014 	struct nlattr **tb = params->tb;
2015 	struct ip6gre_net *ign;
2016 	int err;
2017 
2018 	ip6gre_netlink_parms(data, &nt->parms);
2019 	ign = net_generic(net, ip6gre_net_id);
2020 
2021 	if (nt->parms.collect_md) {
2022 		if (rtnl_dereference(ign->collect_md_tun))
2023 			return -EEXIST;
2024 	} else {
2025 		if (ip6gre_tunnel_find(net, &nt->parms, dev->type))
2026 			return -EEXIST;
2027 	}
2028 
2029 	err = ip6gre_newlink_common(net, dev, tb, data, extack);
2030 	if (!err) {
2031 		ip6gre_tnl_link_config(nt, !tb[IFLA_MTU]);
2032 		ip6gre_tunnel_link_md(ign, nt);
2033 		ip6gre_tunnel_link(net_generic(net, ip6gre_net_id), nt);
2034 	}
2035 	return err;
2036 }
2037 
2038 static struct ip6_tnl *
ip6gre_changelink_common(struct net_device * dev,struct nlattr * tb[],struct nlattr * data[],struct __ip6_tnl_parm * p_p,struct netlink_ext_ack * extack)2039 ip6gre_changelink_common(struct net_device *dev, struct nlattr *tb[],
2040 			 struct nlattr *data[], struct __ip6_tnl_parm *p_p,
2041 			 struct netlink_ext_ack *extack)
2042 {
2043 	struct ip6_tnl *t, *nt = netdev_priv(dev);
2044 	struct net *net = nt->net;
2045 	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
2046 	struct ip_tunnel_encap ipencap;
2047 
2048 	if (dev == ign->fb_tunnel_dev)
2049 		return ERR_PTR(-EINVAL);
2050 
2051 	if (ip6gre_netlink_encap_parms(data, &ipencap)) {
2052 		int err = ip6_tnl_encap_setup(nt, &ipencap);
2053 
2054 		if (err < 0)
2055 			return ERR_PTR(err);
2056 	}
2057 
2058 	ip6gre_netlink_parms(data, p_p);
2059 
2060 	t = ip6gre_tunnel_locate(net, p_p, 0);
2061 
2062 	if (t) {
2063 		if (t->dev != dev)
2064 			return ERR_PTR(-EEXIST);
2065 	} else {
2066 		t = nt;
2067 	}
2068 
2069 	return t;
2070 }
2071 
ip6gre_changelink(struct net_device * dev,struct nlattr * tb[],struct nlattr * data[],struct netlink_ext_ack * extack)2072 static int ip6gre_changelink(struct net_device *dev, struct nlattr *tb[],
2073 			     struct nlattr *data[],
2074 			     struct netlink_ext_ack *extack)
2075 {
2076 	struct ip6_tnl *t = netdev_priv(dev);
2077 	struct ip6gre_net *ign = net_generic(t->net, ip6gre_net_id);
2078 	struct __ip6_tnl_parm p;
2079 
2080 	t = ip6gre_changelink_common(dev, tb, data, &p, extack);
2081 	if (IS_ERR(t))
2082 		return PTR_ERR(t);
2083 
2084 	ip6gre_tunnel_unlink_md(ign, t);
2085 	ip6gre_tunnel_unlink(ign, t);
2086 	ip6gre_tnl_change(t, &p, !tb[IFLA_MTU]);
2087 	ip6gre_tunnel_link_md(ign, t);
2088 	ip6gre_tunnel_link(ign, t);
2089 	return 0;
2090 }
2091 
ip6gre_dellink(struct net_device * dev,struct list_head * head)2092 static void ip6gre_dellink(struct net_device *dev, struct list_head *head)
2093 {
2094 	struct net *net = dev_net(dev);
2095 	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
2096 
2097 	if (dev != ign->fb_tunnel_dev)
2098 		unregister_netdevice_queue(dev, head);
2099 }
2100 
ip6gre_get_size(const struct net_device * dev)2101 static size_t ip6gre_get_size(const struct net_device *dev)
2102 {
2103 	return
2104 		/* IFLA_GRE_LINK */
2105 		nla_total_size(4) +
2106 		/* IFLA_GRE_IFLAGS */
2107 		nla_total_size(2) +
2108 		/* IFLA_GRE_OFLAGS */
2109 		nla_total_size(2) +
2110 		/* IFLA_GRE_IKEY */
2111 		nla_total_size(4) +
2112 		/* IFLA_GRE_OKEY */
2113 		nla_total_size(4) +
2114 		/* IFLA_GRE_LOCAL */
2115 		nla_total_size(sizeof(struct in6_addr)) +
2116 		/* IFLA_GRE_REMOTE */
2117 		nla_total_size(sizeof(struct in6_addr)) +
2118 		/* IFLA_GRE_TTL */
2119 		nla_total_size(1) +
2120 		/* IFLA_GRE_ENCAP_LIMIT */
2121 		nla_total_size(1) +
2122 		/* IFLA_GRE_FLOWINFO */
2123 		nla_total_size(4) +
2124 		/* IFLA_GRE_FLAGS */
2125 		nla_total_size(4) +
2126 		/* IFLA_GRE_ENCAP_TYPE */
2127 		nla_total_size(2) +
2128 		/* IFLA_GRE_ENCAP_FLAGS */
2129 		nla_total_size(2) +
2130 		/* IFLA_GRE_ENCAP_SPORT */
2131 		nla_total_size(2) +
2132 		/* IFLA_GRE_ENCAP_DPORT */
2133 		nla_total_size(2) +
2134 		/* IFLA_GRE_COLLECT_METADATA */
2135 		nla_total_size(0) +
2136 		/* IFLA_GRE_FWMARK */
2137 		nla_total_size(4) +
2138 		/* IFLA_GRE_ERSPAN_INDEX */
2139 		nla_total_size(4) +
2140 		0;
2141 }
2142 
ip6gre_fill_info(struct sk_buff * skb,const struct net_device * dev)2143 static int ip6gre_fill_info(struct sk_buff *skb, const struct net_device *dev)
2144 {
2145 	struct ip6_tnl *t = netdev_priv(dev);
2146 	struct __ip6_tnl_parm *p = &t->parms;
2147 	IP_TUNNEL_DECLARE_FLAGS(o_flags);
2148 
2149 	ip_tunnel_flags_copy(o_flags, p->o_flags);
2150 
2151 	if (p->erspan_ver == 1 || p->erspan_ver == 2) {
2152 		if (!p->collect_md)
2153 			__set_bit(IP_TUNNEL_KEY_BIT, o_flags);
2154 
2155 		if (nla_put_u8(skb, IFLA_GRE_ERSPAN_VER, p->erspan_ver))
2156 			goto nla_put_failure;
2157 
2158 		if (p->erspan_ver == 1) {
2159 			if (nla_put_u32(skb, IFLA_GRE_ERSPAN_INDEX, p->index))
2160 				goto nla_put_failure;
2161 		} else {
2162 			if (nla_put_u8(skb, IFLA_GRE_ERSPAN_DIR, p->dir))
2163 				goto nla_put_failure;
2164 			if (nla_put_u16(skb, IFLA_GRE_ERSPAN_HWID, p->hwid))
2165 				goto nla_put_failure;
2166 		}
2167 	}
2168 
2169 	if (nla_put_u32(skb, IFLA_GRE_LINK, p->link) ||
2170 	    nla_put_be16(skb, IFLA_GRE_IFLAGS,
2171 			 gre_tnl_flags_to_gre_flags(p->i_flags)) ||
2172 	    nla_put_be16(skb, IFLA_GRE_OFLAGS,
2173 			 gre_tnl_flags_to_gre_flags(o_flags)) ||
2174 	    nla_put_be32(skb, IFLA_GRE_IKEY, p->i_key) ||
2175 	    nla_put_be32(skb, IFLA_GRE_OKEY, p->o_key) ||
2176 	    nla_put_in6_addr(skb, IFLA_GRE_LOCAL, &p->laddr) ||
2177 	    nla_put_in6_addr(skb, IFLA_GRE_REMOTE, &p->raddr) ||
2178 	    nla_put_u8(skb, IFLA_GRE_TTL, p->hop_limit) ||
2179 	    nla_put_u8(skb, IFLA_GRE_ENCAP_LIMIT, p->encap_limit) ||
2180 	    nla_put_be32(skb, IFLA_GRE_FLOWINFO, p->flowinfo) ||
2181 	    nla_put_u32(skb, IFLA_GRE_FLAGS, p->flags) ||
2182 	    nla_put_u32(skb, IFLA_GRE_FWMARK, p->fwmark))
2183 		goto nla_put_failure;
2184 
2185 	if (nla_put_u16(skb, IFLA_GRE_ENCAP_TYPE,
2186 			t->encap.type) ||
2187 	    nla_put_be16(skb, IFLA_GRE_ENCAP_SPORT,
2188 			 t->encap.sport) ||
2189 	    nla_put_be16(skb, IFLA_GRE_ENCAP_DPORT,
2190 			 t->encap.dport) ||
2191 	    nla_put_u16(skb, IFLA_GRE_ENCAP_FLAGS,
2192 			t->encap.flags))
2193 		goto nla_put_failure;
2194 
2195 	if (p->collect_md) {
2196 		if (nla_put_flag(skb, IFLA_GRE_COLLECT_METADATA))
2197 			goto nla_put_failure;
2198 	}
2199 
2200 	return 0;
2201 
2202 nla_put_failure:
2203 	return -EMSGSIZE;
2204 }
2205 
2206 static const struct nla_policy ip6gre_policy[IFLA_GRE_MAX + 1] = {
2207 	[IFLA_GRE_LINK]        = { .type = NLA_U32 },
2208 	[IFLA_GRE_IFLAGS]      = { .type = NLA_U16 },
2209 	[IFLA_GRE_OFLAGS]      = { .type = NLA_U16 },
2210 	[IFLA_GRE_IKEY]        = { .type = NLA_U32 },
2211 	[IFLA_GRE_OKEY]        = { .type = NLA_U32 },
2212 	[IFLA_GRE_LOCAL]       = { .len = sizeof_field(struct ipv6hdr, saddr) },
2213 	[IFLA_GRE_REMOTE]      = { .len = sizeof_field(struct ipv6hdr, daddr) },
2214 	[IFLA_GRE_TTL]         = { .type = NLA_U8 },
2215 	[IFLA_GRE_ENCAP_LIMIT] = { .type = NLA_U8 },
2216 	[IFLA_GRE_FLOWINFO]    = { .type = NLA_U32 },
2217 	[IFLA_GRE_FLAGS]       = { .type = NLA_U32 },
2218 	[IFLA_GRE_ENCAP_TYPE]   = { .type = NLA_U16 },
2219 	[IFLA_GRE_ENCAP_FLAGS]  = { .type = NLA_U16 },
2220 	[IFLA_GRE_ENCAP_SPORT]  = { .type = NLA_U16 },
2221 	[IFLA_GRE_ENCAP_DPORT]  = { .type = NLA_U16 },
2222 	[IFLA_GRE_COLLECT_METADATA] = { .type = NLA_FLAG },
2223 	[IFLA_GRE_FWMARK]       = { .type = NLA_U32 },
2224 	[IFLA_GRE_ERSPAN_INDEX] = { .type = NLA_U32 },
2225 	[IFLA_GRE_ERSPAN_VER]	= { .type = NLA_U8 },
2226 	[IFLA_GRE_ERSPAN_DIR]	= { .type = NLA_U8 },
2227 	[IFLA_GRE_ERSPAN_HWID]	= { .type = NLA_U16 },
2228 };
2229 
ip6erspan_tap_setup(struct net_device * dev)2230 static void ip6erspan_tap_setup(struct net_device *dev)
2231 {
2232 	ether_setup(dev);
2233 
2234 	dev->max_mtu = 0;
2235 	dev->netdev_ops = &ip6erspan_netdev_ops;
2236 	dev->needs_free_netdev = true;
2237 	dev->priv_destructor = ip6gre_dev_free;
2238 
2239 	dev->pcpu_stat_type = NETDEV_PCPU_STAT_TSTATS;
2240 	dev->priv_flags &= ~IFF_TX_SKB_SHARING;
2241 	dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
2242 	netif_keep_dst(dev);
2243 }
2244 
ip6erspan_newlink(struct net_device * dev,struct rtnl_newlink_params * params,struct netlink_ext_ack * extack)2245 static int ip6erspan_newlink(struct net_device *dev,
2246 			     struct rtnl_newlink_params *params,
2247 			     struct netlink_ext_ack *extack)
2248 {
2249 	struct net *net = params->link_net ? : dev_net(dev);
2250 	struct ip6_tnl *nt = netdev_priv(dev);
2251 	struct nlattr **data = params->data;
2252 	struct nlattr **tb = params->tb;
2253 	struct ip6gre_net *ign;
2254 	int err;
2255 
2256 	ip6gre_netlink_parms(data, &nt->parms);
2257 	ip6erspan_set_version(data, &nt->parms);
2258 	ign = net_generic(net, ip6gre_net_id);
2259 
2260 	if (nt->parms.collect_md) {
2261 		if (rtnl_dereference(ign->collect_md_tun_erspan))
2262 			return -EEXIST;
2263 	} else {
2264 		if (ip6gre_tunnel_find(net, &nt->parms, dev->type))
2265 			return -EEXIST;
2266 	}
2267 
2268 	err = ip6gre_newlink_common(net, dev, tb, data, extack);
2269 	if (!err) {
2270 		ip6erspan_tnl_link_config(nt, !tb[IFLA_MTU]);
2271 		ip6erspan_tunnel_link_md(ign, nt);
2272 		ip6gre_tunnel_link(net_generic(net, ip6gre_net_id), nt);
2273 	}
2274 	return err;
2275 }
2276 
ip6erspan_tnl_link_config(struct ip6_tnl * t,int set_mtu)2277 static void ip6erspan_tnl_link_config(struct ip6_tnl *t, int set_mtu)
2278 {
2279 	ip6gre_tnl_link_config_common(t);
2280 	ip6gre_tnl_link_config_route(t, set_mtu, ip6erspan_calc_hlen(t));
2281 }
2282 
ip6erspan_tnl_change(struct ip6_tnl * t,const struct __ip6_tnl_parm * p,int set_mtu)2283 static int ip6erspan_tnl_change(struct ip6_tnl *t,
2284 				const struct __ip6_tnl_parm *p, int set_mtu)
2285 {
2286 	ip6gre_tnl_copy_tnl_parm(t, p);
2287 	ip6erspan_tnl_link_config(t, set_mtu);
2288 	return 0;
2289 }
2290 
ip6erspan_changelink(struct net_device * dev,struct nlattr * tb[],struct nlattr * data[],struct netlink_ext_ack * extack)2291 static int ip6erspan_changelink(struct net_device *dev, struct nlattr *tb[],
2292 				struct nlattr *data[],
2293 				struct netlink_ext_ack *extack)
2294 {
2295 	struct ip6gre_net *ign = net_generic(dev_net(dev), ip6gre_net_id);
2296 	struct __ip6_tnl_parm p;
2297 	struct ip6_tnl *t;
2298 
2299 	t = ip6gre_changelink_common(dev, tb, data, &p, extack);
2300 	if (IS_ERR(t))
2301 		return PTR_ERR(t);
2302 
2303 	ip6erspan_set_version(data, &p);
2304 	ip6gre_tunnel_unlink_md(ign, t);
2305 	ip6gre_tunnel_unlink(ign, t);
2306 	ip6erspan_tnl_change(t, &p, !tb[IFLA_MTU]);
2307 	ip6erspan_tunnel_link_md(ign, t);
2308 	ip6gre_tunnel_link(ign, t);
2309 	return 0;
2310 }
2311 
2312 static struct rtnl_link_ops ip6gre_link_ops __read_mostly = {
2313 	.kind		= "ip6gre",
2314 	.maxtype	= IFLA_GRE_MAX,
2315 	.policy		= ip6gre_policy,
2316 	.priv_size	= sizeof(struct ip6_tnl),
2317 	.setup		= ip6gre_tunnel_setup,
2318 	.validate	= ip6gre_tunnel_validate,
2319 	.newlink	= ip6gre_newlink,
2320 	.changelink	= ip6gre_changelink,
2321 	.dellink	= ip6gre_dellink,
2322 	.get_size	= ip6gre_get_size,
2323 	.fill_info	= ip6gre_fill_info,
2324 	.get_link_net	= ip6_tnl_get_link_net,
2325 };
2326 
2327 static struct rtnl_link_ops ip6gre_tap_ops __read_mostly = {
2328 	.kind		= "ip6gretap",
2329 	.maxtype	= IFLA_GRE_MAX,
2330 	.policy		= ip6gre_policy,
2331 	.priv_size	= sizeof(struct ip6_tnl),
2332 	.setup		= ip6gre_tap_setup,
2333 	.validate	= ip6gre_tap_validate,
2334 	.newlink	= ip6gre_newlink,
2335 	.changelink	= ip6gre_changelink,
2336 	.get_size	= ip6gre_get_size,
2337 	.fill_info	= ip6gre_fill_info,
2338 	.get_link_net	= ip6_tnl_get_link_net,
2339 };
2340 
2341 static struct rtnl_link_ops ip6erspan_tap_ops __read_mostly = {
2342 	.kind		= "ip6erspan",
2343 	.maxtype	= IFLA_GRE_MAX,
2344 	.policy		= ip6gre_policy,
2345 	.priv_size	= sizeof(struct ip6_tnl),
2346 	.setup		= ip6erspan_tap_setup,
2347 	.validate	= ip6erspan_tap_validate,
2348 	.newlink	= ip6erspan_newlink,
2349 	.changelink	= ip6erspan_changelink,
2350 	.get_size	= ip6gre_get_size,
2351 	.fill_info	= ip6gre_fill_info,
2352 	.get_link_net	= ip6_tnl_get_link_net,
2353 };
2354 
2355 /*
2356  *	And now the modules code and kernel interface.
2357  */
2358 
ip6gre_init(void)2359 static int __init ip6gre_init(void)
2360 {
2361 	int err;
2362 
2363 	pr_info("GRE over IPv6 tunneling driver\n");
2364 
2365 	err = register_pernet_device(&ip6gre_net_ops);
2366 	if (err < 0)
2367 		return err;
2368 
2369 	err = inet6_add_protocol(&ip6gre_protocol, IPPROTO_GRE);
2370 	if (err < 0) {
2371 		pr_info("%s: can't add protocol\n", __func__);
2372 		goto add_proto_failed;
2373 	}
2374 
2375 	err = rtnl_link_register(&ip6gre_link_ops);
2376 	if (err < 0)
2377 		goto rtnl_link_failed;
2378 
2379 	err = rtnl_link_register(&ip6gre_tap_ops);
2380 	if (err < 0)
2381 		goto tap_ops_failed;
2382 
2383 	err = rtnl_link_register(&ip6erspan_tap_ops);
2384 	if (err < 0)
2385 		goto erspan_link_failed;
2386 
2387 out:
2388 	return err;
2389 
2390 erspan_link_failed:
2391 	rtnl_link_unregister(&ip6gre_tap_ops);
2392 tap_ops_failed:
2393 	rtnl_link_unregister(&ip6gre_link_ops);
2394 rtnl_link_failed:
2395 	inet6_del_protocol(&ip6gre_protocol, IPPROTO_GRE);
2396 add_proto_failed:
2397 	unregister_pernet_device(&ip6gre_net_ops);
2398 	goto out;
2399 }
2400 
ip6gre_fini(void)2401 static void __exit ip6gre_fini(void)
2402 {
2403 	rtnl_link_unregister(&ip6gre_tap_ops);
2404 	rtnl_link_unregister(&ip6gre_link_ops);
2405 	rtnl_link_unregister(&ip6erspan_tap_ops);
2406 	inet6_del_protocol(&ip6gre_protocol, IPPROTO_GRE);
2407 	unregister_pernet_device(&ip6gre_net_ops);
2408 }
2409 
2410 module_init(ip6gre_init);
2411 module_exit(ip6gre_fini);
2412 MODULE_LICENSE("GPL");
2413 MODULE_AUTHOR("D. Kozlov <xeb@mail.ru>");
2414 MODULE_DESCRIPTION("GRE over IPv6 tunneling device");
2415 MODULE_ALIAS_RTNL_LINK("ip6gre");
2416 MODULE_ALIAS_RTNL_LINK("ip6gretap");
2417 MODULE_ALIAS_RTNL_LINK("ip6erspan");
2418 MODULE_ALIAS_NETDEV("ip6gre0");
2419