xref: /openbmc/linux/net/ipv4/ip_tunnel_core.c (revision b0a21810)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (c) 2013 Nicira, Inc.
4  */
5 
6 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
7 
8 #include <linux/types.h>
9 #include <linux/kernel.h>
10 #include <linux/skbuff.h>
11 #include <linux/netdevice.h>
12 #include <linux/in.h>
13 #include <linux/if_arp.h>
14 #include <linux/init.h>
15 #include <linux/in6.h>
16 #include <linux/inetdevice.h>
17 #include <linux/netfilter_ipv4.h>
18 #include <linux/etherdevice.h>
19 #include <linux/if_ether.h>
20 #include <linux/if_vlan.h>
21 #include <linux/static_key.h>
22 
23 #include <net/ip.h>
24 #include <net/icmp.h>
25 #include <net/protocol.h>
26 #include <net/ip_tunnels.h>
27 #include <net/ip6_tunnel.h>
28 #include <net/arp.h>
29 #include <net/checksum.h>
30 #include <net/dsfield.h>
31 #include <net/inet_ecn.h>
32 #include <net/xfrm.h>
33 #include <net/net_namespace.h>
34 #include <net/netns/generic.h>
35 #include <net/rtnetlink.h>
36 #include <net/dst_metadata.h>
37 #include <net/geneve.h>
38 #include <net/vxlan.h>
39 #include <net/erspan.h>
40 
41 const struct ip_tunnel_encap_ops __rcu *
42 		iptun_encaps[MAX_IPTUN_ENCAP_OPS] __read_mostly;
43 EXPORT_SYMBOL(iptun_encaps);
44 
45 const struct ip6_tnl_encap_ops __rcu *
46 		ip6tun_encaps[MAX_IPTUN_ENCAP_OPS] __read_mostly;
47 EXPORT_SYMBOL(ip6tun_encaps);
48 
49 void iptunnel_xmit(struct sock *sk, struct rtable *rt, struct sk_buff *skb,
50 		   __be32 src, __be32 dst, __u8 proto,
51 		   __u8 tos, __u8 ttl, __be16 df, bool xnet)
52 {
53 	int pkt_len = skb->len - skb_inner_network_offset(skb);
54 	struct net *net = dev_net(rt->dst.dev);
55 	struct net_device *dev = skb->dev;
56 	struct iphdr *iph;
57 	int err;
58 
59 	skb_scrub_packet(skb, xnet);
60 
61 	skb_clear_hash_if_not_l4(skb);
62 	skb_dst_set(skb, &rt->dst);
63 	memset(IPCB(skb), 0, sizeof(*IPCB(skb)));
64 
65 	/* Push down and install the IP header. */
66 	skb_push(skb, sizeof(struct iphdr));
67 	skb_reset_network_header(skb);
68 
69 	iph = ip_hdr(skb);
70 
71 	iph->version	=	4;
72 	iph->ihl	=	sizeof(struct iphdr) >> 2;
73 	iph->frag_off	=	ip_mtu_locked(&rt->dst) ? 0 : df;
74 	iph->protocol	=	proto;
75 	iph->tos	=	tos;
76 	iph->daddr	=	dst;
77 	iph->saddr	=	src;
78 	iph->ttl	=	ttl;
79 	__ip_select_ident(net, iph, skb_shinfo(skb)->gso_segs ?: 1);
80 
81 	err = ip_local_out(net, sk, skb);
82 
83 	if (dev) {
84 		if (unlikely(net_xmit_eval(err)))
85 			pkt_len = 0;
86 		iptunnel_xmit_stats(dev, pkt_len);
87 	}
88 }
89 EXPORT_SYMBOL_GPL(iptunnel_xmit);
90 
91 int __iptunnel_pull_header(struct sk_buff *skb, int hdr_len,
92 			   __be16 inner_proto, bool raw_proto, bool xnet)
93 {
94 	if (unlikely(!pskb_may_pull(skb, hdr_len)))
95 		return -ENOMEM;
96 
97 	skb_pull_rcsum(skb, hdr_len);
98 
99 	if (!raw_proto && inner_proto == htons(ETH_P_TEB)) {
100 		struct ethhdr *eh;
101 
102 		if (unlikely(!pskb_may_pull(skb, ETH_HLEN)))
103 			return -ENOMEM;
104 
105 		eh = (struct ethhdr *)skb->data;
106 		if (likely(eth_proto_is_802_3(eh->h_proto)))
107 			skb->protocol = eh->h_proto;
108 		else
109 			skb->protocol = htons(ETH_P_802_2);
110 
111 	} else {
112 		skb->protocol = inner_proto;
113 	}
114 
115 	skb_clear_hash_if_not_l4(skb);
116 	__vlan_hwaccel_clear_tag(skb);
117 	skb_set_queue_mapping(skb, 0);
118 	skb_scrub_packet(skb, xnet);
119 
120 	return iptunnel_pull_offloads(skb);
121 }
122 EXPORT_SYMBOL_GPL(__iptunnel_pull_header);
123 
124 struct metadata_dst *iptunnel_metadata_reply(struct metadata_dst *md,
125 					     gfp_t flags)
126 {
127 	struct metadata_dst *res;
128 	struct ip_tunnel_info *dst, *src;
129 
130 	if (!md || md->type != METADATA_IP_TUNNEL ||
131 	    md->u.tun_info.mode & IP_TUNNEL_INFO_TX)
132 		return NULL;
133 
134 	src = &md->u.tun_info;
135 	res = metadata_dst_alloc(src->options_len, METADATA_IP_TUNNEL, flags);
136 	if (!res)
137 		return NULL;
138 
139 	dst = &res->u.tun_info;
140 	dst->key.tun_id = src->key.tun_id;
141 	if (src->mode & IP_TUNNEL_INFO_IPV6)
142 		memcpy(&dst->key.u.ipv6.dst, &src->key.u.ipv6.src,
143 		       sizeof(struct in6_addr));
144 	else
145 		dst->key.u.ipv4.dst = src->key.u.ipv4.src;
146 	dst->key.tun_flags = src->key.tun_flags;
147 	dst->mode = src->mode | IP_TUNNEL_INFO_TX;
148 	ip_tunnel_info_opts_set(dst, ip_tunnel_info_opts(src),
149 				src->options_len, 0);
150 
151 	return res;
152 }
153 EXPORT_SYMBOL_GPL(iptunnel_metadata_reply);
154 
155 int iptunnel_handle_offloads(struct sk_buff *skb,
156 			     int gso_type_mask)
157 {
158 	int err;
159 
160 	if (likely(!skb->encapsulation)) {
161 		skb_reset_inner_headers(skb);
162 		skb->encapsulation = 1;
163 	}
164 
165 	if (skb_is_gso(skb)) {
166 		err = skb_header_unclone(skb, GFP_ATOMIC);
167 		if (unlikely(err))
168 			return err;
169 		skb_shinfo(skb)->gso_type |= gso_type_mask;
170 		return 0;
171 	}
172 
173 	if (skb->ip_summed != CHECKSUM_PARTIAL) {
174 		skb->ip_summed = CHECKSUM_NONE;
175 		/* We clear encapsulation here to prevent badly-written
176 		 * drivers potentially deciding to offload an inner checksum
177 		 * if we set CHECKSUM_PARTIAL on the outer header.
178 		 * This should go away when the drivers are all fixed.
179 		 */
180 		skb->encapsulation = 0;
181 	}
182 
183 	return 0;
184 }
185 EXPORT_SYMBOL_GPL(iptunnel_handle_offloads);
186 
187 /* Often modified stats are per cpu, other are shared (netdev->stats) */
188 void ip_tunnel_get_stats64(struct net_device *dev,
189 			   struct rtnl_link_stats64 *tot)
190 {
191 	int i;
192 
193 	netdev_stats_to_stats64(tot, &dev->stats);
194 
195 	for_each_possible_cpu(i) {
196 		const struct pcpu_sw_netstats *tstats =
197 						   per_cpu_ptr(dev->tstats, i);
198 		u64 rx_packets, rx_bytes, tx_packets, tx_bytes;
199 		unsigned int start;
200 
201 		do {
202 			start = u64_stats_fetch_begin_irq(&tstats->syncp);
203 			rx_packets = tstats->rx_packets;
204 			tx_packets = tstats->tx_packets;
205 			rx_bytes = tstats->rx_bytes;
206 			tx_bytes = tstats->tx_bytes;
207 		} while (u64_stats_fetch_retry_irq(&tstats->syncp, start));
208 
209 		tot->rx_packets += rx_packets;
210 		tot->tx_packets += tx_packets;
211 		tot->rx_bytes   += rx_bytes;
212 		tot->tx_bytes   += tx_bytes;
213 	}
214 }
215 EXPORT_SYMBOL_GPL(ip_tunnel_get_stats64);
216 
217 static const struct nla_policy ip_tun_policy[LWTUNNEL_IP_MAX + 1] = {
218 	[LWTUNNEL_IP_ID]	= { .type = NLA_U64 },
219 	[LWTUNNEL_IP_DST]	= { .type = NLA_U32 },
220 	[LWTUNNEL_IP_SRC]	= { .type = NLA_U32 },
221 	[LWTUNNEL_IP_TTL]	= { .type = NLA_U8 },
222 	[LWTUNNEL_IP_TOS]	= { .type = NLA_U8 },
223 	[LWTUNNEL_IP_FLAGS]	= { .type = NLA_U16 },
224 	[LWTUNNEL_IP_OPTS]	= { .type = NLA_NESTED },
225 };
226 
227 static const struct nla_policy ip_opts_policy[LWTUNNEL_IP_OPTS_MAX + 1] = {
228 	[LWTUNNEL_IP_OPTS_GENEVE]	= { .type = NLA_NESTED },
229 	[LWTUNNEL_IP_OPTS_VXLAN]	= { .type = NLA_NESTED },
230 	[LWTUNNEL_IP_OPTS_ERSPAN]	= { .type = NLA_NESTED },
231 };
232 
233 static const struct nla_policy
234 geneve_opt_policy[LWTUNNEL_IP_OPT_GENEVE_MAX + 1] = {
235 	[LWTUNNEL_IP_OPT_GENEVE_CLASS]	= { .type = NLA_U16 },
236 	[LWTUNNEL_IP_OPT_GENEVE_TYPE]	= { .type = NLA_U8 },
237 	[LWTUNNEL_IP_OPT_GENEVE_DATA]	= { .type = NLA_BINARY, .len = 128 },
238 };
239 
240 static const struct nla_policy
241 vxlan_opt_policy[LWTUNNEL_IP_OPT_VXLAN_MAX + 1] = {
242 	[LWTUNNEL_IP_OPT_VXLAN_GBP]	= { .type = NLA_U32 },
243 };
244 
245 static const struct nla_policy
246 erspan_opt_policy[LWTUNNEL_IP_OPT_ERSPAN_MAX + 1] = {
247 	[LWTUNNEL_IP_OPT_ERSPAN_VER]	= { .type = NLA_U8 },
248 	[LWTUNNEL_IP_OPT_ERSPAN_INDEX]	= { .type = NLA_U32 },
249 	[LWTUNNEL_IP_OPT_ERSPAN_DIR]	= { .type = NLA_U8 },
250 	[LWTUNNEL_IP_OPT_ERSPAN_HWID]	= { .type = NLA_U8 },
251 };
252 
253 static int ip_tun_parse_opts_geneve(struct nlattr *attr,
254 				    struct ip_tunnel_info *info,
255 				    struct netlink_ext_ack *extack)
256 {
257 	struct nlattr *tb[LWTUNNEL_IP_OPT_GENEVE_MAX + 1];
258 	int data_len, err;
259 
260 	err = nla_parse_nested_deprecated(tb, LWTUNNEL_IP_OPT_GENEVE_MAX,
261 					  attr, geneve_opt_policy, extack);
262 	if (err)
263 		return err;
264 
265 	if (!tb[LWTUNNEL_IP_OPT_GENEVE_CLASS] ||
266 	    !tb[LWTUNNEL_IP_OPT_GENEVE_TYPE] ||
267 	    !tb[LWTUNNEL_IP_OPT_GENEVE_DATA])
268 		return -EINVAL;
269 
270 	attr = tb[LWTUNNEL_IP_OPT_GENEVE_DATA];
271 	data_len = nla_len(attr);
272 	if (data_len % 4)
273 		return -EINVAL;
274 
275 	if (info) {
276 		struct geneve_opt *opt = ip_tunnel_info_opts(info);
277 
278 		memcpy(opt->opt_data, nla_data(attr), data_len);
279 		opt->length = data_len / 4;
280 		attr = tb[LWTUNNEL_IP_OPT_GENEVE_CLASS];
281 		opt->opt_class = nla_get_be16(attr);
282 		attr = tb[LWTUNNEL_IP_OPT_GENEVE_TYPE];
283 		opt->type = nla_get_u8(attr);
284 		info->key.tun_flags |= TUNNEL_GENEVE_OPT;
285 	}
286 
287 	return sizeof(struct geneve_opt) + data_len;
288 }
289 
290 static int ip_tun_parse_opts_vxlan(struct nlattr *attr,
291 				   struct ip_tunnel_info *info,
292 				   struct netlink_ext_ack *extack)
293 {
294 	struct nlattr *tb[LWTUNNEL_IP_OPT_VXLAN_MAX + 1];
295 	int err;
296 
297 	err = nla_parse_nested_deprecated(tb, LWTUNNEL_IP_OPT_VXLAN_MAX,
298 					  attr, vxlan_opt_policy, extack);
299 	if (err)
300 		return err;
301 
302 	if (!tb[LWTUNNEL_IP_OPT_VXLAN_GBP])
303 		return -EINVAL;
304 
305 	if (info) {
306 		struct vxlan_metadata *md = ip_tunnel_info_opts(info);
307 
308 		attr = tb[LWTUNNEL_IP_OPT_VXLAN_GBP];
309 		md->gbp = nla_get_u32(attr);
310 		info->key.tun_flags |= TUNNEL_VXLAN_OPT;
311 	}
312 
313 	return sizeof(struct vxlan_metadata);
314 }
315 
316 static int ip_tun_parse_opts_erspan(struct nlattr *attr,
317 				    struct ip_tunnel_info *info,
318 				    struct netlink_ext_ack *extack)
319 {
320 	struct nlattr *tb[LWTUNNEL_IP_OPT_ERSPAN_MAX + 1];
321 	int err;
322 
323 	err = nla_parse_nested_deprecated(tb, LWTUNNEL_IP_OPT_ERSPAN_MAX,
324 					  attr, erspan_opt_policy, extack);
325 	if (err)
326 		return err;
327 
328 	if (!tb[LWTUNNEL_IP_OPT_ERSPAN_VER])
329 		return -EINVAL;
330 
331 	if (info) {
332 		struct erspan_metadata *md = ip_tunnel_info_opts(info);
333 
334 		attr = tb[LWTUNNEL_IP_OPT_ERSPAN_VER];
335 		md->version = nla_get_u8(attr);
336 
337 		if (md->version == 1 && tb[LWTUNNEL_IP_OPT_ERSPAN_INDEX]) {
338 			attr = tb[LWTUNNEL_IP_OPT_ERSPAN_INDEX];
339 			md->u.index = nla_get_be32(attr);
340 		} else if (md->version == 2 && tb[LWTUNNEL_IP_OPT_ERSPAN_DIR] &&
341 			   tb[LWTUNNEL_IP_OPT_ERSPAN_HWID]) {
342 			attr = tb[LWTUNNEL_IP_OPT_ERSPAN_DIR];
343 			md->u.md2.dir = nla_get_u8(attr);
344 			attr = tb[LWTUNNEL_IP_OPT_ERSPAN_HWID];
345 			set_hwid(&md->u.md2, nla_get_u8(attr));
346 		} else {
347 			return -EINVAL;
348 		}
349 
350 		info->key.tun_flags |= TUNNEL_ERSPAN_OPT;
351 	}
352 
353 	return sizeof(struct erspan_metadata);
354 }
355 
356 static int ip_tun_parse_opts(struct nlattr *attr, struct ip_tunnel_info *info,
357 			     struct netlink_ext_ack *extack)
358 {
359 	struct nlattr *tb[LWTUNNEL_IP_OPTS_MAX + 1];
360 	int err;
361 
362 	if (!attr)
363 		return 0;
364 
365 	err = nla_parse_nested_deprecated(tb, LWTUNNEL_IP_OPTS_MAX, attr,
366 					  ip_opts_policy, extack);
367 	if (err)
368 		return err;
369 
370 	if (tb[LWTUNNEL_IP_OPTS_GENEVE])
371 		err = ip_tun_parse_opts_geneve(tb[LWTUNNEL_IP_OPTS_GENEVE],
372 					       info, extack);
373 	else if (tb[LWTUNNEL_IP_OPTS_VXLAN])
374 		err = ip_tun_parse_opts_vxlan(tb[LWTUNNEL_IP_OPTS_VXLAN],
375 					      info, extack);
376 	else if (tb[LWTUNNEL_IP_OPTS_ERSPAN])
377 		err = ip_tun_parse_opts_erspan(tb[LWTUNNEL_IP_OPTS_ERSPAN],
378 					       info, extack);
379 	else
380 		err = -EINVAL;
381 
382 	return err;
383 }
384 
385 static int ip_tun_get_optlen(struct nlattr *attr,
386 			     struct netlink_ext_ack *extack)
387 {
388 	return ip_tun_parse_opts(attr, NULL, extack);
389 }
390 
391 static int ip_tun_set_opts(struct nlattr *attr, struct ip_tunnel_info *info,
392 			   struct netlink_ext_ack *extack)
393 {
394 	return ip_tun_parse_opts(attr, info, extack);
395 }
396 
397 static int ip_tun_build_state(struct nlattr *attr,
398 			      unsigned int family, const void *cfg,
399 			      struct lwtunnel_state **ts,
400 			      struct netlink_ext_ack *extack)
401 {
402 	struct nlattr *tb[LWTUNNEL_IP_MAX + 1];
403 	struct lwtunnel_state *new_state;
404 	struct ip_tunnel_info *tun_info;
405 	int err, opt_len;
406 
407 	err = nla_parse_nested_deprecated(tb, LWTUNNEL_IP_MAX, attr,
408 					  ip_tun_policy, extack);
409 	if (err < 0)
410 		return err;
411 
412 	opt_len = ip_tun_get_optlen(tb[LWTUNNEL_IP_OPTS], extack);
413 	if (opt_len < 0)
414 		return opt_len;
415 
416 	new_state = lwtunnel_state_alloc(sizeof(*tun_info) + opt_len);
417 	if (!new_state)
418 		return -ENOMEM;
419 
420 	new_state->type = LWTUNNEL_ENCAP_IP;
421 
422 	tun_info = lwt_tun_info(new_state);
423 
424 	err = ip_tun_set_opts(tb[LWTUNNEL_IP_OPTS], tun_info, extack);
425 	if (err < 0) {
426 		lwtstate_free(new_state);
427 		return err;
428 	}
429 
430 #ifdef CONFIG_DST_CACHE
431 	err = dst_cache_init(&tun_info->dst_cache, GFP_KERNEL);
432 	if (err) {
433 		lwtstate_free(new_state);
434 		return err;
435 	}
436 #endif
437 
438 	if (tb[LWTUNNEL_IP_ID])
439 		tun_info->key.tun_id = nla_get_be64(tb[LWTUNNEL_IP_ID]);
440 
441 	if (tb[LWTUNNEL_IP_DST])
442 		tun_info->key.u.ipv4.dst = nla_get_in_addr(tb[LWTUNNEL_IP_DST]);
443 
444 	if (tb[LWTUNNEL_IP_SRC])
445 		tun_info->key.u.ipv4.src = nla_get_in_addr(tb[LWTUNNEL_IP_SRC]);
446 
447 	if (tb[LWTUNNEL_IP_TTL])
448 		tun_info->key.ttl = nla_get_u8(tb[LWTUNNEL_IP_TTL]);
449 
450 	if (tb[LWTUNNEL_IP_TOS])
451 		tun_info->key.tos = nla_get_u8(tb[LWTUNNEL_IP_TOS]);
452 
453 	if (tb[LWTUNNEL_IP_FLAGS])
454 		tun_info->key.tun_flags |= nla_get_be16(tb[LWTUNNEL_IP_FLAGS]);
455 
456 	tun_info->mode = IP_TUNNEL_INFO_TX;
457 	tun_info->options_len = opt_len;
458 
459 	*ts = new_state;
460 
461 	return 0;
462 }
463 
464 static void ip_tun_destroy_state(struct lwtunnel_state *lwtstate)
465 {
466 #ifdef CONFIG_DST_CACHE
467 	struct ip_tunnel_info *tun_info = lwt_tun_info(lwtstate);
468 
469 	dst_cache_destroy(&tun_info->dst_cache);
470 #endif
471 }
472 
473 static int ip_tun_fill_encap_opts_geneve(struct sk_buff *skb,
474 					 struct ip_tunnel_info *tun_info)
475 {
476 	struct geneve_opt *opt;
477 	struct nlattr *nest;
478 
479 	nest = nla_nest_start_noflag(skb, LWTUNNEL_IP_OPTS_GENEVE);
480 	if (!nest)
481 		return -ENOMEM;
482 
483 	opt = ip_tunnel_info_opts(tun_info);
484 	if (nla_put_be16(skb, LWTUNNEL_IP_OPT_GENEVE_CLASS, opt->opt_class) ||
485 	    nla_put_u8(skb, LWTUNNEL_IP_OPT_GENEVE_TYPE, opt->type) ||
486 	    nla_put(skb, LWTUNNEL_IP_OPT_GENEVE_DATA, opt->length * 4,
487 		    opt->opt_data)) {
488 		nla_nest_cancel(skb, nest);
489 		return -ENOMEM;
490 	}
491 
492 	nla_nest_end(skb, nest);
493 	return 0;
494 }
495 
496 static int ip_tun_fill_encap_opts_vxlan(struct sk_buff *skb,
497 					struct ip_tunnel_info *tun_info)
498 {
499 	struct vxlan_metadata *md;
500 	struct nlattr *nest;
501 
502 	nest = nla_nest_start_noflag(skb, LWTUNNEL_IP_OPTS_VXLAN);
503 	if (!nest)
504 		return -ENOMEM;
505 
506 	md = ip_tunnel_info_opts(tun_info);
507 	if (nla_put_u32(skb, LWTUNNEL_IP_OPT_VXLAN_GBP, md->gbp)) {
508 		nla_nest_cancel(skb, nest);
509 		return -ENOMEM;
510 	}
511 
512 	nla_nest_end(skb, nest);
513 	return 0;
514 }
515 
516 static int ip_tun_fill_encap_opts_erspan(struct sk_buff *skb,
517 					 struct ip_tunnel_info *tun_info)
518 {
519 	struct erspan_metadata *md;
520 	struct nlattr *nest;
521 
522 	nest = nla_nest_start_noflag(skb, LWTUNNEL_IP_OPTS_ERSPAN);
523 	if (!nest)
524 		return -ENOMEM;
525 
526 	md = ip_tunnel_info_opts(tun_info);
527 	if (nla_put_u32(skb, LWTUNNEL_IP_OPT_ERSPAN_VER, md->version))
528 		goto err;
529 
530 	if (md->version == 1 &&
531 	    nla_put_be32(skb, LWTUNNEL_IP_OPT_ERSPAN_INDEX, md->u.index))
532 		goto err;
533 
534 	if (md->version == 2 &&
535 	    (nla_put_u8(skb, LWTUNNEL_IP_OPT_ERSPAN_DIR, md->u.md2.dir) ||
536 	     nla_put_u8(skb, LWTUNNEL_IP_OPT_ERSPAN_HWID,
537 			get_hwid(&md->u.md2))))
538 		goto err;
539 
540 	nla_nest_end(skb, nest);
541 	return 0;
542 err:
543 	nla_nest_cancel(skb, nest);
544 	return -ENOMEM;
545 }
546 
547 static int ip_tun_fill_encap_opts(struct sk_buff *skb, int type,
548 				  struct ip_tunnel_info *tun_info)
549 {
550 	struct nlattr *nest;
551 	int err = 0;
552 
553 	if (!(tun_info->key.tun_flags &
554 	      (TUNNEL_GENEVE_OPT | TUNNEL_VXLAN_OPT | TUNNEL_ERSPAN_OPT)))
555 		return 0;
556 
557 	nest = nla_nest_start_noflag(skb, type);
558 	if (!nest)
559 		return -ENOMEM;
560 
561 	if (tun_info->key.tun_flags & TUNNEL_GENEVE_OPT)
562 		err = ip_tun_fill_encap_opts_geneve(skb, tun_info);
563 	else if (tun_info->key.tun_flags & TUNNEL_VXLAN_OPT)
564 		err = ip_tun_fill_encap_opts_vxlan(skb, tun_info);
565 	else if (tun_info->key.tun_flags & TUNNEL_ERSPAN_OPT)
566 		err = ip_tun_fill_encap_opts_erspan(skb, tun_info);
567 
568 	if (err) {
569 		nla_nest_cancel(skb, nest);
570 		return err;
571 	}
572 
573 	nla_nest_end(skb, nest);
574 	return 0;
575 }
576 
577 static int ip_tun_fill_encap_info(struct sk_buff *skb,
578 				  struct lwtunnel_state *lwtstate)
579 {
580 	struct ip_tunnel_info *tun_info = lwt_tun_info(lwtstate);
581 
582 	if (nla_put_be64(skb, LWTUNNEL_IP_ID, tun_info->key.tun_id,
583 			 LWTUNNEL_IP_PAD) ||
584 	    nla_put_in_addr(skb, LWTUNNEL_IP_DST, tun_info->key.u.ipv4.dst) ||
585 	    nla_put_in_addr(skb, LWTUNNEL_IP_SRC, tun_info->key.u.ipv4.src) ||
586 	    nla_put_u8(skb, LWTUNNEL_IP_TOS, tun_info->key.tos) ||
587 	    nla_put_u8(skb, LWTUNNEL_IP_TTL, tun_info->key.ttl) ||
588 	    nla_put_be16(skb, LWTUNNEL_IP_FLAGS, tun_info->key.tun_flags) ||
589 	    ip_tun_fill_encap_opts(skb, LWTUNNEL_IP_OPTS, tun_info))
590 		return -ENOMEM;
591 
592 	return 0;
593 }
594 
595 static int ip_tun_opts_nlsize(struct ip_tunnel_info *info)
596 {
597 	int opt_len;
598 
599 	if (!(info->key.tun_flags &
600 	      (TUNNEL_GENEVE_OPT | TUNNEL_VXLAN_OPT | TUNNEL_ERSPAN_OPT)))
601 		return 0;
602 
603 	opt_len = nla_total_size(0);		/* LWTUNNEL_IP_OPTS */
604 	if (info->key.tun_flags & TUNNEL_GENEVE_OPT) {
605 		struct geneve_opt *opt = ip_tunnel_info_opts(info);
606 
607 		opt_len += nla_total_size(0)	/* LWTUNNEL_IP_OPTS_GENEVE */
608 			   + nla_total_size(2)	/* OPT_GENEVE_CLASS */
609 			   + nla_total_size(1)	/* OPT_GENEVE_TYPE */
610 			   + nla_total_size(opt->length * 4);
611 						/* OPT_GENEVE_DATA */
612 	} else if (info->key.tun_flags & TUNNEL_VXLAN_OPT) {
613 		opt_len += nla_total_size(0)	/* LWTUNNEL_IP_OPTS_VXLAN */
614 			   + nla_total_size(4);	/* OPT_VXLAN_GBP */
615 	} else if (info->key.tun_flags & TUNNEL_ERSPAN_OPT) {
616 		opt_len += nla_total_size(0)	/* LWTUNNEL_IP_OPTS_ERSPAN */
617 			   + nla_total_size(1)	/* OPT_ERSPAN_VER */
618 			   + nla_total_size(4);	/* OPT_ERSPAN_INDEX/DIR/HWID */
619 	}
620 
621 	return opt_len;
622 }
623 
624 static int ip_tun_encap_nlsize(struct lwtunnel_state *lwtstate)
625 {
626 	return nla_total_size_64bit(8)	/* LWTUNNEL_IP_ID */
627 		+ nla_total_size(4)	/* LWTUNNEL_IP_DST */
628 		+ nla_total_size(4)	/* LWTUNNEL_IP_SRC */
629 		+ nla_total_size(1)	/* LWTUNNEL_IP_TOS */
630 		+ nla_total_size(1)	/* LWTUNNEL_IP_TTL */
631 		+ nla_total_size(2)	/* LWTUNNEL_IP_FLAGS */
632 		+ ip_tun_opts_nlsize(lwt_tun_info(lwtstate));
633 					/* LWTUNNEL_IP_OPTS */
634 }
635 
636 static int ip_tun_cmp_encap(struct lwtunnel_state *a, struct lwtunnel_state *b)
637 {
638 	struct ip_tunnel_info *info_a = lwt_tun_info(a);
639 	struct ip_tunnel_info *info_b = lwt_tun_info(b);
640 
641 	return memcmp(info_a, info_b, sizeof(info_a->key)) ||
642 	       info_a->mode != info_b->mode ||
643 	       info_a->options_len != info_b->options_len ||
644 	       memcmp(ip_tunnel_info_opts(info_a),
645 		      ip_tunnel_info_opts(info_b), info_a->options_len);
646 }
647 
648 static const struct lwtunnel_encap_ops ip_tun_lwt_ops = {
649 	.build_state = ip_tun_build_state,
650 	.destroy_state = ip_tun_destroy_state,
651 	.fill_encap = ip_tun_fill_encap_info,
652 	.get_encap_size = ip_tun_encap_nlsize,
653 	.cmp_encap = ip_tun_cmp_encap,
654 	.owner = THIS_MODULE,
655 };
656 
657 static const struct nla_policy ip6_tun_policy[LWTUNNEL_IP6_MAX + 1] = {
658 	[LWTUNNEL_IP6_ID]		= { .type = NLA_U64 },
659 	[LWTUNNEL_IP6_DST]		= { .len = sizeof(struct in6_addr) },
660 	[LWTUNNEL_IP6_SRC]		= { .len = sizeof(struct in6_addr) },
661 	[LWTUNNEL_IP6_HOPLIMIT]		= { .type = NLA_U8 },
662 	[LWTUNNEL_IP6_TC]		= { .type = NLA_U8 },
663 	[LWTUNNEL_IP6_FLAGS]		= { .type = NLA_U16 },
664 };
665 
666 static int ip6_tun_build_state(struct nlattr *attr,
667 			       unsigned int family, const void *cfg,
668 			       struct lwtunnel_state **ts,
669 			       struct netlink_ext_ack *extack)
670 {
671 	struct nlattr *tb[LWTUNNEL_IP6_MAX + 1];
672 	struct lwtunnel_state *new_state;
673 	struct ip_tunnel_info *tun_info;
674 	int err, opt_len;
675 
676 	err = nla_parse_nested_deprecated(tb, LWTUNNEL_IP6_MAX, attr,
677 					  ip6_tun_policy, extack);
678 	if (err < 0)
679 		return err;
680 
681 	opt_len = ip_tun_get_optlen(tb[LWTUNNEL_IP6_OPTS], extack);
682 	if (opt_len < 0)
683 		return opt_len;
684 
685 	new_state = lwtunnel_state_alloc(sizeof(*tun_info) + opt_len);
686 	if (!new_state)
687 		return -ENOMEM;
688 
689 	new_state->type = LWTUNNEL_ENCAP_IP6;
690 
691 	tun_info = lwt_tun_info(new_state);
692 
693 	err = ip_tun_set_opts(tb[LWTUNNEL_IP6_OPTS], tun_info, extack);
694 	if (err < 0) {
695 		lwtstate_free(new_state);
696 		return err;
697 	}
698 
699 	if (tb[LWTUNNEL_IP6_ID])
700 		tun_info->key.tun_id = nla_get_be64(tb[LWTUNNEL_IP6_ID]);
701 
702 	if (tb[LWTUNNEL_IP6_DST])
703 		tun_info->key.u.ipv6.dst = nla_get_in6_addr(tb[LWTUNNEL_IP6_DST]);
704 
705 	if (tb[LWTUNNEL_IP6_SRC])
706 		tun_info->key.u.ipv6.src = nla_get_in6_addr(tb[LWTUNNEL_IP6_SRC]);
707 
708 	if (tb[LWTUNNEL_IP6_HOPLIMIT])
709 		tun_info->key.ttl = nla_get_u8(tb[LWTUNNEL_IP6_HOPLIMIT]);
710 
711 	if (tb[LWTUNNEL_IP6_TC])
712 		tun_info->key.tos = nla_get_u8(tb[LWTUNNEL_IP6_TC]);
713 
714 	if (tb[LWTUNNEL_IP6_FLAGS])
715 		tun_info->key.tun_flags |= nla_get_be16(tb[LWTUNNEL_IP6_FLAGS]);
716 
717 	tun_info->mode = IP_TUNNEL_INFO_TX | IP_TUNNEL_INFO_IPV6;
718 	tun_info->options_len = opt_len;
719 
720 	*ts = new_state;
721 
722 	return 0;
723 }
724 
725 static int ip6_tun_fill_encap_info(struct sk_buff *skb,
726 				   struct lwtunnel_state *lwtstate)
727 {
728 	struct ip_tunnel_info *tun_info = lwt_tun_info(lwtstate);
729 
730 	if (nla_put_be64(skb, LWTUNNEL_IP6_ID, tun_info->key.tun_id,
731 			 LWTUNNEL_IP6_PAD) ||
732 	    nla_put_in6_addr(skb, LWTUNNEL_IP6_DST, &tun_info->key.u.ipv6.dst) ||
733 	    nla_put_in6_addr(skb, LWTUNNEL_IP6_SRC, &tun_info->key.u.ipv6.src) ||
734 	    nla_put_u8(skb, LWTUNNEL_IP6_TC, tun_info->key.tos) ||
735 	    nla_put_u8(skb, LWTUNNEL_IP6_HOPLIMIT, tun_info->key.ttl) ||
736 	    nla_put_be16(skb, LWTUNNEL_IP6_FLAGS, tun_info->key.tun_flags) ||
737 	    ip_tun_fill_encap_opts(skb, LWTUNNEL_IP6_OPTS, tun_info))
738 		return -ENOMEM;
739 
740 	return 0;
741 }
742 
743 static int ip6_tun_encap_nlsize(struct lwtunnel_state *lwtstate)
744 {
745 	return nla_total_size_64bit(8)	/* LWTUNNEL_IP6_ID */
746 		+ nla_total_size(16)	/* LWTUNNEL_IP6_DST */
747 		+ nla_total_size(16)	/* LWTUNNEL_IP6_SRC */
748 		+ nla_total_size(1)	/* LWTUNNEL_IP6_HOPLIMIT */
749 		+ nla_total_size(1)	/* LWTUNNEL_IP6_TC */
750 		+ nla_total_size(2)	/* LWTUNNEL_IP6_FLAGS */
751 		+ ip_tun_opts_nlsize(lwt_tun_info(lwtstate));
752 					/* LWTUNNEL_IP6_OPTS */
753 }
754 
755 static const struct lwtunnel_encap_ops ip6_tun_lwt_ops = {
756 	.build_state = ip6_tun_build_state,
757 	.fill_encap = ip6_tun_fill_encap_info,
758 	.get_encap_size = ip6_tun_encap_nlsize,
759 	.cmp_encap = ip_tun_cmp_encap,
760 	.owner = THIS_MODULE,
761 };
762 
763 void __init ip_tunnel_core_init(void)
764 {
765 	/* If you land here, make sure whether increasing ip_tunnel_info's
766 	 * options_len is a reasonable choice with its usage in front ends
767 	 * (f.e., it's part of flow keys, etc).
768 	 */
769 	BUILD_BUG_ON(IP_TUNNEL_OPTS_MAX != 255);
770 
771 	lwtunnel_encap_add_ops(&ip_tun_lwt_ops, LWTUNNEL_ENCAP_IP);
772 	lwtunnel_encap_add_ops(&ip6_tun_lwt_ops, LWTUNNEL_ENCAP_IP6);
773 }
774 
775 DEFINE_STATIC_KEY_FALSE(ip_tunnel_metadata_cnt);
776 EXPORT_SYMBOL(ip_tunnel_metadata_cnt);
777 
778 void ip_tunnel_need_metadata(void)
779 {
780 	static_branch_inc(&ip_tunnel_metadata_cnt);
781 }
782 EXPORT_SYMBOL_GPL(ip_tunnel_need_metadata);
783 
784 void ip_tunnel_unneed_metadata(void)
785 {
786 	static_branch_dec(&ip_tunnel_metadata_cnt);
787 }
788 EXPORT_SYMBOL_GPL(ip_tunnel_unneed_metadata);
789