xref: /linux/drivers/net/geneve.c (revision 9a736fcb096b43b68af8329eb12abc8256dceaba)
1 /*
2  * GENEVE: Generic Network Virtualization Encapsulation
3  *
4  * Copyright (c) 2015 Red Hat, Inc.
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License version 2 as
8  * published by the Free Software Foundation.
9  */
10 
11 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
12 
13 #include <linux/kernel.h>
14 #include <linux/module.h>
15 #include <linux/etherdevice.h>
16 #include <linux/hash.h>
17 #include <net/dst_metadata.h>
18 #include <net/gro_cells.h>
19 #include <net/rtnetlink.h>
20 #include <net/geneve.h>
21 #include <net/protocol.h>
22 
23 #define GENEVE_NETDEV_VER	"0.6"
24 
25 #define GENEVE_UDP_PORT		6081
26 
27 #define GENEVE_N_VID		(1u << 24)
28 #define GENEVE_VID_MASK		(GENEVE_N_VID - 1)
29 
30 #define VNI_HASH_BITS		10
31 #define VNI_HASH_SIZE		(1<<VNI_HASH_BITS)
32 
33 static bool log_ecn_error = true;
34 module_param(log_ecn_error, bool, 0644);
35 MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN");
36 
37 #define GENEVE_VER 0
38 #define GENEVE_BASE_HLEN (sizeof(struct udphdr) + sizeof(struct genevehdr))
39 
40 /* per-network namespace private data for this module */
41 struct geneve_net {
42 	struct list_head	geneve_list;
43 	struct list_head	sock_list;
44 };
45 
46 static int geneve_net_id;
47 
48 union geneve_addr {
49 	struct sockaddr_in sin;
50 	struct sockaddr_in6 sin6;
51 	struct sockaddr sa;
52 };
53 
54 static union geneve_addr geneve_remote_unspec = { .sa.sa_family = AF_UNSPEC, };
55 
56 /* Pseudo network device */
57 struct geneve_dev {
58 	struct hlist_node  hlist;	/* vni hash table */
59 	struct net	   *net;	/* netns for packet i/o */
60 	struct net_device  *dev;	/* netdev for geneve tunnel */
61 	struct geneve_sock __rcu *sock4;	/* IPv4 socket used for geneve tunnel */
62 #if IS_ENABLED(CONFIG_IPV6)
63 	struct geneve_sock __rcu *sock6;	/* IPv6 socket used for geneve tunnel */
64 #endif
65 	u8                 vni[3];	/* virtual network ID for tunnel */
66 	u8                 ttl;		/* TTL override */
67 	u8                 tos;		/* TOS override */
68 	union geneve_addr  remote;	/* IP address for link partner */
69 	struct list_head   next;	/* geneve's per namespace list */
70 	__be32		   label;	/* IPv6 flowlabel override */
71 	__be16		   dst_port;
72 	bool		   collect_md;
73 	struct gro_cells   gro_cells;
74 	u32		   flags;
75 	struct dst_cache   dst_cache;
76 };
77 
78 /* Geneve device flags */
79 #define GENEVE_F_UDP_ZERO_CSUM_TX	BIT(0)
80 #define GENEVE_F_UDP_ZERO_CSUM6_TX	BIT(1)
81 #define GENEVE_F_UDP_ZERO_CSUM6_RX	BIT(2)
82 
83 struct geneve_sock {
84 	bool			collect_md;
85 	struct list_head	list;
86 	struct socket		*sock;
87 	struct rcu_head		rcu;
88 	int			refcnt;
89 	struct hlist_head	vni_list[VNI_HASH_SIZE];
90 	u32			flags;
91 };
92 
93 static inline __u32 geneve_net_vni_hash(u8 vni[3])
94 {
95 	__u32 vnid;
96 
97 	vnid = (vni[0] << 16) | (vni[1] << 8) | vni[2];
98 	return hash_32(vnid, VNI_HASH_BITS);
99 }
100 
101 static __be64 vni_to_tunnel_id(const __u8 *vni)
102 {
103 #ifdef __BIG_ENDIAN
104 	return (vni[0] << 16) | (vni[1] << 8) | vni[2];
105 #else
106 	return (__force __be64)(((__force u64)vni[0] << 40) |
107 				((__force u64)vni[1] << 48) |
108 				((__force u64)vni[2] << 56));
109 #endif
110 }
111 
112 static sa_family_t geneve_get_sk_family(struct geneve_sock *gs)
113 {
114 	return gs->sock->sk->sk_family;
115 }
116 
117 static struct geneve_dev *geneve_lookup(struct geneve_sock *gs,
118 					__be32 addr, u8 vni[])
119 {
120 	struct hlist_head *vni_list_head;
121 	struct geneve_dev *geneve;
122 	__u32 hash;
123 
124 	/* Find the device for this VNI */
125 	hash = geneve_net_vni_hash(vni);
126 	vni_list_head = &gs->vni_list[hash];
127 	hlist_for_each_entry_rcu(geneve, vni_list_head, hlist) {
128 		if (!memcmp(vni, geneve->vni, sizeof(geneve->vni)) &&
129 		    addr == geneve->remote.sin.sin_addr.s_addr)
130 			return geneve;
131 	}
132 	return NULL;
133 }
134 
135 #if IS_ENABLED(CONFIG_IPV6)
136 static struct geneve_dev *geneve6_lookup(struct geneve_sock *gs,
137 					 struct in6_addr addr6, u8 vni[])
138 {
139 	struct hlist_head *vni_list_head;
140 	struct geneve_dev *geneve;
141 	__u32 hash;
142 
143 	/* Find the device for this VNI */
144 	hash = geneve_net_vni_hash(vni);
145 	vni_list_head = &gs->vni_list[hash];
146 	hlist_for_each_entry_rcu(geneve, vni_list_head, hlist) {
147 		if (!memcmp(vni, geneve->vni, sizeof(geneve->vni)) &&
148 		    ipv6_addr_equal(&addr6, &geneve->remote.sin6.sin6_addr))
149 			return geneve;
150 	}
151 	return NULL;
152 }
153 #endif
154 
155 static inline struct genevehdr *geneve_hdr(const struct sk_buff *skb)
156 {
157 	return (struct genevehdr *)(udp_hdr(skb) + 1);
158 }
159 
160 static struct geneve_dev *geneve_lookup_skb(struct geneve_sock *gs,
161 					    struct sk_buff *skb)
162 {
163 	u8 *vni;
164 	__be32 addr;
165 	static u8 zero_vni[3];
166 #if IS_ENABLED(CONFIG_IPV6)
167 	static struct in6_addr zero_addr6;
168 #endif
169 
170 	if (geneve_get_sk_family(gs) == AF_INET) {
171 		struct iphdr *iph;
172 
173 		iph = ip_hdr(skb); /* outer IP header... */
174 
175 		if (gs->collect_md) {
176 			vni = zero_vni;
177 			addr = 0;
178 		} else {
179 			vni = geneve_hdr(skb)->vni;
180 			addr = iph->saddr;
181 		}
182 
183 		return geneve_lookup(gs, addr, vni);
184 #if IS_ENABLED(CONFIG_IPV6)
185 	} else if (geneve_get_sk_family(gs) == AF_INET6) {
186 		struct ipv6hdr *ip6h;
187 		struct in6_addr addr6;
188 
189 		ip6h = ipv6_hdr(skb); /* outer IPv6 header... */
190 
191 		if (gs->collect_md) {
192 			vni = zero_vni;
193 			addr6 = zero_addr6;
194 		} else {
195 			vni = geneve_hdr(skb)->vni;
196 			addr6 = ip6h->saddr;
197 		}
198 
199 		return geneve6_lookup(gs, addr6, vni);
200 #endif
201 	}
202 	return NULL;
203 }
204 
205 /* geneve receive/decap routine */
206 static void geneve_rx(struct geneve_dev *geneve, struct geneve_sock *gs,
207 		      struct sk_buff *skb)
208 {
209 	struct genevehdr *gnvh = geneve_hdr(skb);
210 	struct metadata_dst *tun_dst = NULL;
211 	struct pcpu_sw_netstats *stats;
212 	int err = 0;
213 	void *oiph;
214 
215 	if (ip_tunnel_collect_metadata() || gs->collect_md) {
216 		__be16 flags;
217 
218 		flags = TUNNEL_KEY | TUNNEL_GENEVE_OPT |
219 			(gnvh->oam ? TUNNEL_OAM : 0) |
220 			(gnvh->critical ? TUNNEL_CRIT_OPT : 0);
221 
222 		tun_dst = udp_tun_rx_dst(skb, geneve_get_sk_family(gs), flags,
223 					 vni_to_tunnel_id(gnvh->vni),
224 					 gnvh->opt_len * 4);
225 		if (!tun_dst)
226 			goto drop;
227 		/* Update tunnel dst according to Geneve options. */
228 		ip_tunnel_info_opts_set(&tun_dst->u.tun_info,
229 					gnvh->options, gnvh->opt_len * 4);
230 	} else {
231 		/* Drop packets w/ critical options,
232 		 * since we don't support any...
233 		 */
234 		if (gnvh->critical)
235 			goto drop;
236 	}
237 
238 	skb_reset_mac_header(skb);
239 	skb->protocol = eth_type_trans(skb, geneve->dev);
240 	skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN);
241 
242 	if (tun_dst)
243 		skb_dst_set(skb, &tun_dst->dst);
244 
245 	/* Ignore packet loops (and multicast echo) */
246 	if (ether_addr_equal(eth_hdr(skb)->h_source, geneve->dev->dev_addr))
247 		goto drop;
248 
249 	oiph = skb_network_header(skb);
250 	skb_reset_network_header(skb);
251 
252 	if (geneve_get_sk_family(gs) == AF_INET)
253 		err = IP_ECN_decapsulate(oiph, skb);
254 #if IS_ENABLED(CONFIG_IPV6)
255 	else
256 		err = IP6_ECN_decapsulate(oiph, skb);
257 #endif
258 
259 	if (unlikely(err)) {
260 		if (log_ecn_error) {
261 			if (geneve_get_sk_family(gs) == AF_INET)
262 				net_info_ratelimited("non-ECT from %pI4 "
263 						     "with TOS=%#x\n",
264 						     &((struct iphdr *)oiph)->saddr,
265 						     ((struct iphdr *)oiph)->tos);
266 #if IS_ENABLED(CONFIG_IPV6)
267 			else
268 				net_info_ratelimited("non-ECT from %pI6\n",
269 						     &((struct ipv6hdr *)oiph)->saddr);
270 #endif
271 		}
272 		if (err > 1) {
273 			++geneve->dev->stats.rx_frame_errors;
274 			++geneve->dev->stats.rx_errors;
275 			goto drop;
276 		}
277 	}
278 
279 	stats = this_cpu_ptr(geneve->dev->tstats);
280 	u64_stats_update_begin(&stats->syncp);
281 	stats->rx_packets++;
282 	stats->rx_bytes += skb->len;
283 	u64_stats_update_end(&stats->syncp);
284 
285 	gro_cells_receive(&geneve->gro_cells, skb);
286 	return;
287 drop:
288 	/* Consume bad packet */
289 	kfree_skb(skb);
290 }
291 
292 /* Setup stats when device is created */
293 static int geneve_init(struct net_device *dev)
294 {
295 	struct geneve_dev *geneve = netdev_priv(dev);
296 	int err;
297 
298 	dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
299 	if (!dev->tstats)
300 		return -ENOMEM;
301 
302 	err = gro_cells_init(&geneve->gro_cells, dev);
303 	if (err) {
304 		free_percpu(dev->tstats);
305 		return err;
306 	}
307 
308 	err = dst_cache_init(&geneve->dst_cache, GFP_KERNEL);
309 	if (err) {
310 		free_percpu(dev->tstats);
311 		gro_cells_destroy(&geneve->gro_cells);
312 		return err;
313 	}
314 
315 	return 0;
316 }
317 
318 static void geneve_uninit(struct net_device *dev)
319 {
320 	struct geneve_dev *geneve = netdev_priv(dev);
321 
322 	dst_cache_destroy(&geneve->dst_cache);
323 	gro_cells_destroy(&geneve->gro_cells);
324 	free_percpu(dev->tstats);
325 }
326 
327 /* Callback from net/ipv4/udp.c to receive packets */
328 static int geneve_udp_encap_recv(struct sock *sk, struct sk_buff *skb)
329 {
330 	struct genevehdr *geneveh;
331 	struct geneve_dev *geneve;
332 	struct geneve_sock *gs;
333 	int opts_len;
334 
335 	/* Need Geneve and inner Ethernet header to be present */
336 	if (unlikely(!pskb_may_pull(skb, GENEVE_BASE_HLEN)))
337 		goto drop;
338 
339 	/* Return packets with reserved bits set */
340 	geneveh = geneve_hdr(skb);
341 	if (unlikely(geneveh->ver != GENEVE_VER))
342 		goto drop;
343 
344 	if (unlikely(geneveh->proto_type != htons(ETH_P_TEB)))
345 		goto drop;
346 
347 	gs = rcu_dereference_sk_user_data(sk);
348 	if (!gs)
349 		goto drop;
350 
351 	geneve = geneve_lookup_skb(gs, skb);
352 	if (!geneve)
353 		goto drop;
354 
355 	opts_len = geneveh->opt_len * 4;
356 	if (iptunnel_pull_header(skb, GENEVE_BASE_HLEN + opts_len,
357 				 htons(ETH_P_TEB),
358 				 !net_eq(geneve->net, dev_net(geneve->dev))))
359 		goto drop;
360 
361 	geneve_rx(geneve, gs, skb);
362 	return 0;
363 
364 drop:
365 	/* Consume bad packet */
366 	kfree_skb(skb);
367 	return 0;
368 }
369 
370 static struct socket *geneve_create_sock(struct net *net, bool ipv6,
371 					 __be16 port, u32 flags)
372 {
373 	struct socket *sock;
374 	struct udp_port_cfg udp_conf;
375 	int err;
376 
377 	memset(&udp_conf, 0, sizeof(udp_conf));
378 
379 	if (ipv6) {
380 		udp_conf.family = AF_INET6;
381 		udp_conf.ipv6_v6only = 1;
382 		udp_conf.use_udp6_rx_checksums =
383 		    !(flags & GENEVE_F_UDP_ZERO_CSUM6_RX);
384 	} else {
385 		udp_conf.family = AF_INET;
386 		udp_conf.local_ip.s_addr = htonl(INADDR_ANY);
387 	}
388 
389 	udp_conf.local_udp_port = port;
390 
391 	/* Open UDP socket */
392 	err = udp_sock_create(net, &udp_conf, &sock);
393 	if (err < 0)
394 		return ERR_PTR(err);
395 
396 	return sock;
397 }
398 
399 static int geneve_hlen(struct genevehdr *gh)
400 {
401 	return sizeof(*gh) + gh->opt_len * 4;
402 }
403 
404 static struct sk_buff **geneve_gro_receive(struct sock *sk,
405 					   struct sk_buff **head,
406 					   struct sk_buff *skb)
407 {
408 	struct sk_buff *p, **pp = NULL;
409 	struct genevehdr *gh, *gh2;
410 	unsigned int hlen, gh_len, off_gnv;
411 	const struct packet_offload *ptype;
412 	__be16 type;
413 	int flush = 1;
414 
415 	off_gnv = skb_gro_offset(skb);
416 	hlen = off_gnv + sizeof(*gh);
417 	gh = skb_gro_header_fast(skb, off_gnv);
418 	if (skb_gro_header_hard(skb, hlen)) {
419 		gh = skb_gro_header_slow(skb, hlen, off_gnv);
420 		if (unlikely(!gh))
421 			goto out;
422 	}
423 
424 	if (gh->ver != GENEVE_VER || gh->oam)
425 		goto out;
426 	gh_len = geneve_hlen(gh);
427 
428 	hlen = off_gnv + gh_len;
429 	if (skb_gro_header_hard(skb, hlen)) {
430 		gh = skb_gro_header_slow(skb, hlen, off_gnv);
431 		if (unlikely(!gh))
432 			goto out;
433 	}
434 
435 	for (p = *head; p; p = p->next) {
436 		if (!NAPI_GRO_CB(p)->same_flow)
437 			continue;
438 
439 		gh2 = (struct genevehdr *)(p->data + off_gnv);
440 		if (gh->opt_len != gh2->opt_len ||
441 		    memcmp(gh, gh2, gh_len)) {
442 			NAPI_GRO_CB(p)->same_flow = 0;
443 			continue;
444 		}
445 	}
446 
447 	type = gh->proto_type;
448 
449 	rcu_read_lock();
450 	ptype = gro_find_receive_by_type(type);
451 	if (!ptype)
452 		goto out_unlock;
453 
454 	skb_gro_pull(skb, gh_len);
455 	skb_gro_postpull_rcsum(skb, gh, gh_len);
456 	pp = call_gro_receive(ptype->callbacks.gro_receive, head, skb);
457 	flush = 0;
458 
459 out_unlock:
460 	rcu_read_unlock();
461 out:
462 	NAPI_GRO_CB(skb)->flush |= flush;
463 
464 	return pp;
465 }
466 
467 static int geneve_gro_complete(struct sock *sk, struct sk_buff *skb,
468 			       int nhoff)
469 {
470 	struct genevehdr *gh;
471 	struct packet_offload *ptype;
472 	__be16 type;
473 	int gh_len;
474 	int err = -ENOSYS;
475 
476 	gh = (struct genevehdr *)(skb->data + nhoff);
477 	gh_len = geneve_hlen(gh);
478 	type = gh->proto_type;
479 
480 	rcu_read_lock();
481 	ptype = gro_find_complete_by_type(type);
482 	if (ptype)
483 		err = ptype->callbacks.gro_complete(skb, nhoff + gh_len);
484 
485 	rcu_read_unlock();
486 
487 	skb_set_inner_mac_header(skb, nhoff + gh_len);
488 
489 	return err;
490 }
491 
492 /* Create new listen socket if needed */
493 static struct geneve_sock *geneve_socket_create(struct net *net, __be16 port,
494 						bool ipv6, u32 flags)
495 {
496 	struct geneve_net *gn = net_generic(net, geneve_net_id);
497 	struct geneve_sock *gs;
498 	struct socket *sock;
499 	struct udp_tunnel_sock_cfg tunnel_cfg;
500 	int h;
501 
502 	gs = kzalloc(sizeof(*gs), GFP_KERNEL);
503 	if (!gs)
504 		return ERR_PTR(-ENOMEM);
505 
506 	sock = geneve_create_sock(net, ipv6, port, flags);
507 	if (IS_ERR(sock)) {
508 		kfree(gs);
509 		return ERR_CAST(sock);
510 	}
511 
512 	gs->sock = sock;
513 	gs->refcnt = 1;
514 	for (h = 0; h < VNI_HASH_SIZE; ++h)
515 		INIT_HLIST_HEAD(&gs->vni_list[h]);
516 
517 	/* Initialize the geneve udp offloads structure */
518 	udp_tunnel_notify_add_rx_port(gs->sock, UDP_TUNNEL_TYPE_GENEVE);
519 
520 	/* Mark socket as an encapsulation socket */
521 	memset(&tunnel_cfg, 0, sizeof(tunnel_cfg));
522 	tunnel_cfg.sk_user_data = gs;
523 	tunnel_cfg.encap_type = 1;
524 	tunnel_cfg.gro_receive = geneve_gro_receive;
525 	tunnel_cfg.gro_complete = geneve_gro_complete;
526 	tunnel_cfg.encap_rcv = geneve_udp_encap_recv;
527 	tunnel_cfg.encap_destroy = NULL;
528 	setup_udp_tunnel_sock(net, sock, &tunnel_cfg);
529 	list_add(&gs->list, &gn->sock_list);
530 	return gs;
531 }
532 
533 static void __geneve_sock_release(struct geneve_sock *gs)
534 {
535 	if (!gs || --gs->refcnt)
536 		return;
537 
538 	list_del(&gs->list);
539 	udp_tunnel_notify_del_rx_port(gs->sock, UDP_TUNNEL_TYPE_GENEVE);
540 	udp_tunnel_sock_release(gs->sock);
541 	kfree_rcu(gs, rcu);
542 }
543 
544 static void geneve_sock_release(struct geneve_dev *geneve)
545 {
546 	struct geneve_sock *gs4 = rtnl_dereference(geneve->sock4);
547 #if IS_ENABLED(CONFIG_IPV6)
548 	struct geneve_sock *gs6 = rtnl_dereference(geneve->sock6);
549 
550 	rcu_assign_pointer(geneve->sock6, NULL);
551 #endif
552 
553 	rcu_assign_pointer(geneve->sock4, NULL);
554 	synchronize_net();
555 
556 	__geneve_sock_release(gs4);
557 #if IS_ENABLED(CONFIG_IPV6)
558 	__geneve_sock_release(gs6);
559 #endif
560 }
561 
562 static struct geneve_sock *geneve_find_sock(struct geneve_net *gn,
563 					    sa_family_t family,
564 					    __be16 dst_port)
565 {
566 	struct geneve_sock *gs;
567 
568 	list_for_each_entry(gs, &gn->sock_list, list) {
569 		if (inet_sk(gs->sock->sk)->inet_sport == dst_port &&
570 		    geneve_get_sk_family(gs) == family) {
571 			return gs;
572 		}
573 	}
574 	return NULL;
575 }
576 
577 static int geneve_sock_add(struct geneve_dev *geneve, bool ipv6)
578 {
579 	struct net *net = geneve->net;
580 	struct geneve_net *gn = net_generic(net, geneve_net_id);
581 	struct geneve_sock *gs;
582 	__u32 hash;
583 
584 	gs = geneve_find_sock(gn, ipv6 ? AF_INET6 : AF_INET, geneve->dst_port);
585 	if (gs) {
586 		gs->refcnt++;
587 		goto out;
588 	}
589 
590 	gs = geneve_socket_create(net, geneve->dst_port, ipv6, geneve->flags);
591 	if (IS_ERR(gs))
592 		return PTR_ERR(gs);
593 
594 out:
595 	gs->collect_md = geneve->collect_md;
596 	gs->flags = geneve->flags;
597 #if IS_ENABLED(CONFIG_IPV6)
598 	if (ipv6)
599 		rcu_assign_pointer(geneve->sock6, gs);
600 	else
601 #endif
602 		rcu_assign_pointer(geneve->sock4, gs);
603 
604 	hash = geneve_net_vni_hash(geneve->vni);
605 	hlist_add_head_rcu(&geneve->hlist, &gs->vni_list[hash]);
606 	return 0;
607 }
608 
609 static int geneve_open(struct net_device *dev)
610 {
611 	struct geneve_dev *geneve = netdev_priv(dev);
612 	bool ipv6 = geneve->remote.sa.sa_family == AF_INET6;
613 	bool metadata = geneve->collect_md;
614 	int ret = 0;
615 
616 #if IS_ENABLED(CONFIG_IPV6)
617 	if (ipv6 || metadata)
618 		ret = geneve_sock_add(geneve, true);
619 #endif
620 	if (!ret && (!ipv6 || metadata))
621 		ret = geneve_sock_add(geneve, false);
622 	if (ret < 0)
623 		geneve_sock_release(geneve);
624 
625 	return ret;
626 }
627 
628 static int geneve_stop(struct net_device *dev)
629 {
630 	struct geneve_dev *geneve = netdev_priv(dev);
631 
632 	if (!hlist_unhashed(&geneve->hlist))
633 		hlist_del_rcu(&geneve->hlist);
634 	geneve_sock_release(geneve);
635 	return 0;
636 }
637 
638 static void geneve_build_header(struct genevehdr *geneveh,
639 				__be16 tun_flags, u8 vni[3],
640 				u8 options_len, u8 *options)
641 {
642 	geneveh->ver = GENEVE_VER;
643 	geneveh->opt_len = options_len / 4;
644 	geneveh->oam = !!(tun_flags & TUNNEL_OAM);
645 	geneveh->critical = !!(tun_flags & TUNNEL_CRIT_OPT);
646 	geneveh->rsvd1 = 0;
647 	memcpy(geneveh->vni, vni, 3);
648 	geneveh->proto_type = htons(ETH_P_TEB);
649 	geneveh->rsvd2 = 0;
650 
651 	memcpy(geneveh->options, options, options_len);
652 }
653 
654 static int geneve_build_skb(struct rtable *rt, struct sk_buff *skb,
655 			    __be16 tun_flags, u8 vni[3], u8 opt_len, u8 *opt,
656 			    u32 flags, bool xnet)
657 {
658 	struct genevehdr *gnvh;
659 	int min_headroom;
660 	int err;
661 	bool udp_sum = !(flags & GENEVE_F_UDP_ZERO_CSUM_TX);
662 
663 	skb_scrub_packet(skb, xnet);
664 
665 	min_headroom = LL_RESERVED_SPACE(rt->dst.dev) + rt->dst.header_len
666 			+ GENEVE_BASE_HLEN + opt_len + sizeof(struct iphdr);
667 	err = skb_cow_head(skb, min_headroom);
668 	if (unlikely(err))
669 		goto free_rt;
670 
671 	err = udp_tunnel_handle_offloads(skb, udp_sum);
672 	if (err)
673 		goto free_rt;
674 
675 	gnvh = (struct genevehdr *)__skb_push(skb, sizeof(*gnvh) + opt_len);
676 	geneve_build_header(gnvh, tun_flags, vni, opt_len, opt);
677 
678 	skb_set_inner_protocol(skb, htons(ETH_P_TEB));
679 	return 0;
680 
681 free_rt:
682 	ip_rt_put(rt);
683 	return err;
684 }
685 
686 #if IS_ENABLED(CONFIG_IPV6)
687 static int geneve6_build_skb(struct dst_entry *dst, struct sk_buff *skb,
688 			     __be16 tun_flags, u8 vni[3], u8 opt_len, u8 *opt,
689 			     u32 flags, bool xnet)
690 {
691 	struct genevehdr *gnvh;
692 	int min_headroom;
693 	int err;
694 	bool udp_sum = !(flags & GENEVE_F_UDP_ZERO_CSUM6_TX);
695 
696 	skb_scrub_packet(skb, xnet);
697 
698 	min_headroom = LL_RESERVED_SPACE(dst->dev) + dst->header_len
699 			+ GENEVE_BASE_HLEN + opt_len + sizeof(struct ipv6hdr);
700 	err = skb_cow_head(skb, min_headroom);
701 	if (unlikely(err))
702 		goto free_dst;
703 
704 	err = udp_tunnel_handle_offloads(skb, udp_sum);
705 	if (err)
706 		goto free_dst;
707 
708 	gnvh = (struct genevehdr *)__skb_push(skb, sizeof(*gnvh) + opt_len);
709 	geneve_build_header(gnvh, tun_flags, vni, opt_len, opt);
710 
711 	skb_set_inner_protocol(skb, htons(ETH_P_TEB));
712 	return 0;
713 
714 free_dst:
715 	dst_release(dst);
716 	return err;
717 }
718 #endif
719 
720 static struct rtable *geneve_get_v4_rt(struct sk_buff *skb,
721 				       struct net_device *dev,
722 				       struct flowi4 *fl4,
723 				       struct ip_tunnel_info *info)
724 {
725 	bool use_cache = ip_tunnel_dst_cache_usable(skb, info);
726 	struct geneve_dev *geneve = netdev_priv(dev);
727 	struct dst_cache *dst_cache;
728 	struct rtable *rt = NULL;
729 	__u8 tos;
730 
731 	if (!rcu_dereference(geneve->sock4))
732 		return ERR_PTR(-EIO);
733 
734 	memset(fl4, 0, sizeof(*fl4));
735 	fl4->flowi4_mark = skb->mark;
736 	fl4->flowi4_proto = IPPROTO_UDP;
737 
738 	if (info) {
739 		fl4->daddr = info->key.u.ipv4.dst;
740 		fl4->saddr = info->key.u.ipv4.src;
741 		fl4->flowi4_tos = RT_TOS(info->key.tos);
742 		dst_cache = &info->dst_cache;
743 	} else {
744 		tos = geneve->tos;
745 		if (tos == 1) {
746 			const struct iphdr *iip = ip_hdr(skb);
747 
748 			tos = ip_tunnel_get_dsfield(iip, skb);
749 			use_cache = false;
750 		}
751 
752 		fl4->flowi4_tos = RT_TOS(tos);
753 		fl4->daddr = geneve->remote.sin.sin_addr.s_addr;
754 		dst_cache = &geneve->dst_cache;
755 	}
756 
757 	if (use_cache) {
758 		rt = dst_cache_get_ip4(dst_cache, &fl4->saddr);
759 		if (rt)
760 			return rt;
761 	}
762 
763 	rt = ip_route_output_key(geneve->net, fl4);
764 	if (IS_ERR(rt)) {
765 		netdev_dbg(dev, "no route to %pI4\n", &fl4->daddr);
766 		return ERR_PTR(-ENETUNREACH);
767 	}
768 	if (rt->dst.dev == dev) { /* is this necessary? */
769 		netdev_dbg(dev, "circular route to %pI4\n", &fl4->daddr);
770 		ip_rt_put(rt);
771 		return ERR_PTR(-ELOOP);
772 	}
773 	if (use_cache)
774 		dst_cache_set_ip4(dst_cache, &rt->dst, fl4->saddr);
775 	return rt;
776 }
777 
778 #if IS_ENABLED(CONFIG_IPV6)
779 static struct dst_entry *geneve_get_v6_dst(struct sk_buff *skb,
780 					   struct net_device *dev,
781 					   struct flowi6 *fl6,
782 					   struct ip_tunnel_info *info)
783 {
784 	bool use_cache = ip_tunnel_dst_cache_usable(skb, info);
785 	struct geneve_dev *geneve = netdev_priv(dev);
786 	struct dst_entry *dst = NULL;
787 	struct dst_cache *dst_cache;
788 	struct geneve_sock *gs6;
789 	__u8 prio;
790 
791 	gs6 = rcu_dereference(geneve->sock6);
792 	if (!gs6)
793 		return ERR_PTR(-EIO);
794 
795 	memset(fl6, 0, sizeof(*fl6));
796 	fl6->flowi6_mark = skb->mark;
797 	fl6->flowi6_proto = IPPROTO_UDP;
798 
799 	if (info) {
800 		fl6->daddr = info->key.u.ipv6.dst;
801 		fl6->saddr = info->key.u.ipv6.src;
802 		fl6->flowlabel = ip6_make_flowinfo(RT_TOS(info->key.tos),
803 						   info->key.label);
804 		dst_cache = &info->dst_cache;
805 	} else {
806 		prio = geneve->tos;
807 		if (prio == 1) {
808 			const struct iphdr *iip = ip_hdr(skb);
809 
810 			prio = ip_tunnel_get_dsfield(iip, skb);
811 			use_cache = false;
812 		}
813 
814 		fl6->flowlabel = ip6_make_flowinfo(RT_TOS(prio),
815 						   geneve->label);
816 		fl6->daddr = geneve->remote.sin6.sin6_addr;
817 		dst_cache = &geneve->dst_cache;
818 	}
819 
820 	if (use_cache) {
821 		dst = dst_cache_get_ip6(dst_cache, &fl6->saddr);
822 		if (dst)
823 			return dst;
824 	}
825 
826 	if (ipv6_stub->ipv6_dst_lookup(geneve->net, gs6->sock->sk, &dst, fl6)) {
827 		netdev_dbg(dev, "no route to %pI6\n", &fl6->daddr);
828 		return ERR_PTR(-ENETUNREACH);
829 	}
830 	if (dst->dev == dev) { /* is this necessary? */
831 		netdev_dbg(dev, "circular route to %pI6\n", &fl6->daddr);
832 		dst_release(dst);
833 		return ERR_PTR(-ELOOP);
834 	}
835 
836 	if (use_cache)
837 		dst_cache_set_ip6(dst_cache, dst, &fl6->saddr);
838 	return dst;
839 }
840 #endif
841 
842 /* Convert 64 bit tunnel ID to 24 bit VNI. */
843 static void tunnel_id_to_vni(__be64 tun_id, __u8 *vni)
844 {
845 #ifdef __BIG_ENDIAN
846 	vni[0] = (__force __u8)(tun_id >> 16);
847 	vni[1] = (__force __u8)(tun_id >> 8);
848 	vni[2] = (__force __u8)tun_id;
849 #else
850 	vni[0] = (__force __u8)((__force u64)tun_id >> 40);
851 	vni[1] = (__force __u8)((__force u64)tun_id >> 48);
852 	vni[2] = (__force __u8)((__force u64)tun_id >> 56);
853 #endif
854 }
855 
856 static netdev_tx_t geneve_xmit_skb(struct sk_buff *skb, struct net_device *dev,
857 				   struct ip_tunnel_info *info)
858 {
859 	struct geneve_dev *geneve = netdev_priv(dev);
860 	struct geneve_sock *gs4;
861 	struct rtable *rt = NULL;
862 	int err = -EINVAL;
863 	struct flowi4 fl4;
864 	__u8 tos, ttl;
865 	__be16 sport;
866 	__be16 df;
867 	bool xnet = !net_eq(geneve->net, dev_net(geneve->dev));
868 	u32 flags = geneve->flags;
869 
870 	gs4 = rcu_dereference(geneve->sock4);
871 	if (!gs4)
872 		goto tx_error;
873 
874 	if (geneve->collect_md) {
875 		if (unlikely(!info || !(info->mode & IP_TUNNEL_INFO_TX))) {
876 			netdev_dbg(dev, "no tunnel metadata\n");
877 			goto tx_error;
878 		}
879 		if (info && ip_tunnel_info_af(info) != AF_INET)
880 			goto tx_error;
881 	}
882 
883 	rt = geneve_get_v4_rt(skb, dev, &fl4, info);
884 	if (IS_ERR(rt)) {
885 		err = PTR_ERR(rt);
886 		goto tx_error;
887 	}
888 
889 	sport = udp_flow_src_port(geneve->net, skb, 1, USHRT_MAX, true);
890 	skb_reset_mac_header(skb);
891 
892 	if (info) {
893 		const struct ip_tunnel_key *key = &info->key;
894 		u8 *opts = NULL;
895 		u8 vni[3];
896 
897 		tunnel_id_to_vni(key->tun_id, vni);
898 		if (info->options_len)
899 			opts = ip_tunnel_info_opts(info);
900 
901 		if (key->tun_flags & TUNNEL_CSUM)
902 			flags &= ~GENEVE_F_UDP_ZERO_CSUM_TX;
903 		else
904 			flags |= GENEVE_F_UDP_ZERO_CSUM_TX;
905 
906 		err = geneve_build_skb(rt, skb, key->tun_flags, vni,
907 				       info->options_len, opts, flags, xnet);
908 		if (unlikely(err))
909 			goto tx_error;
910 
911 		tos = ip_tunnel_ecn_encap(key->tos, ip_hdr(skb), skb);
912 		ttl = key->ttl;
913 		df = key->tun_flags & TUNNEL_DONT_FRAGMENT ? htons(IP_DF) : 0;
914 	} else {
915 		err = geneve_build_skb(rt, skb, 0, geneve->vni,
916 				       0, NULL, flags, xnet);
917 		if (unlikely(err))
918 			goto tx_error;
919 
920 		tos = ip_tunnel_ecn_encap(fl4.flowi4_tos, ip_hdr(skb), skb);
921 		ttl = geneve->ttl;
922 		if (!ttl && IN_MULTICAST(ntohl(fl4.daddr)))
923 			ttl = 1;
924 		ttl = ttl ? : ip4_dst_hoplimit(&rt->dst);
925 		df = 0;
926 	}
927 	udp_tunnel_xmit_skb(rt, gs4->sock->sk, skb, fl4.saddr, fl4.daddr,
928 			    tos, ttl, df, sport, geneve->dst_port,
929 			    !net_eq(geneve->net, dev_net(geneve->dev)),
930 			    !!(flags & GENEVE_F_UDP_ZERO_CSUM_TX));
931 
932 	return NETDEV_TX_OK;
933 
934 tx_error:
935 	dev_kfree_skb(skb);
936 
937 	if (err == -ELOOP)
938 		dev->stats.collisions++;
939 	else if (err == -ENETUNREACH)
940 		dev->stats.tx_carrier_errors++;
941 
942 	dev->stats.tx_errors++;
943 	return NETDEV_TX_OK;
944 }
945 
946 #if IS_ENABLED(CONFIG_IPV6)
947 static netdev_tx_t geneve6_xmit_skb(struct sk_buff *skb, struct net_device *dev,
948 				    struct ip_tunnel_info *info)
949 {
950 	struct geneve_dev *geneve = netdev_priv(dev);
951 	struct dst_entry *dst = NULL;
952 	struct geneve_sock *gs6;
953 	int err = -EINVAL;
954 	struct flowi6 fl6;
955 	__u8 prio, ttl;
956 	__be16 sport;
957 	__be32 label;
958 	bool xnet = !net_eq(geneve->net, dev_net(geneve->dev));
959 	u32 flags = geneve->flags;
960 
961 	gs6 = rcu_dereference(geneve->sock6);
962 	if (!gs6)
963 		goto tx_error;
964 
965 	if (geneve->collect_md) {
966 		if (unlikely(!info || !(info->mode & IP_TUNNEL_INFO_TX))) {
967 			netdev_dbg(dev, "no tunnel metadata\n");
968 			goto tx_error;
969 		}
970 	}
971 
972 	dst = geneve_get_v6_dst(skb, dev, &fl6, info);
973 	if (IS_ERR(dst)) {
974 		err = PTR_ERR(dst);
975 		goto tx_error;
976 	}
977 
978 	sport = udp_flow_src_port(geneve->net, skb, 1, USHRT_MAX, true);
979 	skb_reset_mac_header(skb);
980 
981 	if (info) {
982 		const struct ip_tunnel_key *key = &info->key;
983 		u8 *opts = NULL;
984 		u8 vni[3];
985 
986 		tunnel_id_to_vni(key->tun_id, vni);
987 		if (info->options_len)
988 			opts = ip_tunnel_info_opts(info);
989 
990 		if (key->tun_flags & TUNNEL_CSUM)
991 			flags &= ~GENEVE_F_UDP_ZERO_CSUM6_TX;
992 		else
993 			flags |= GENEVE_F_UDP_ZERO_CSUM6_TX;
994 
995 		err = geneve6_build_skb(dst, skb, key->tun_flags, vni,
996 					info->options_len, opts,
997 					flags, xnet);
998 		if (unlikely(err))
999 			goto tx_error;
1000 
1001 		prio = ip_tunnel_ecn_encap(key->tos, ip_hdr(skb), skb);
1002 		ttl = key->ttl;
1003 		label = info->key.label;
1004 	} else {
1005 		err = geneve6_build_skb(dst, skb, 0, geneve->vni,
1006 					0, NULL, flags, xnet);
1007 		if (unlikely(err))
1008 			goto tx_error;
1009 
1010 		prio = ip_tunnel_ecn_encap(ip6_tclass(fl6.flowlabel),
1011 					   ip_hdr(skb), skb);
1012 		ttl = geneve->ttl;
1013 		if (!ttl && ipv6_addr_is_multicast(&fl6.daddr))
1014 			ttl = 1;
1015 		ttl = ttl ? : ip6_dst_hoplimit(dst);
1016 		label = geneve->label;
1017 	}
1018 
1019 	udp_tunnel6_xmit_skb(dst, gs6->sock->sk, skb, dev,
1020 			     &fl6.saddr, &fl6.daddr, prio, ttl, label,
1021 			     sport, geneve->dst_port,
1022 			     !!(flags & GENEVE_F_UDP_ZERO_CSUM6_TX));
1023 	return NETDEV_TX_OK;
1024 
1025 tx_error:
1026 	dev_kfree_skb(skb);
1027 
1028 	if (err == -ELOOP)
1029 		dev->stats.collisions++;
1030 	else if (err == -ENETUNREACH)
1031 		dev->stats.tx_carrier_errors++;
1032 
1033 	dev->stats.tx_errors++;
1034 	return NETDEV_TX_OK;
1035 }
1036 #endif
1037 
1038 static netdev_tx_t geneve_xmit(struct sk_buff *skb, struct net_device *dev)
1039 {
1040 	struct geneve_dev *geneve = netdev_priv(dev);
1041 	struct ip_tunnel_info *info = NULL;
1042 
1043 	if (geneve->collect_md)
1044 		info = skb_tunnel_info(skb);
1045 
1046 #if IS_ENABLED(CONFIG_IPV6)
1047 	if ((info && ip_tunnel_info_af(info) == AF_INET6) ||
1048 	    (!info && geneve->remote.sa.sa_family == AF_INET6))
1049 		return geneve6_xmit_skb(skb, dev, info);
1050 #endif
1051 	return geneve_xmit_skb(skb, dev, info);
1052 }
1053 
1054 static int __geneve_change_mtu(struct net_device *dev, int new_mtu, bool strict)
1055 {
1056 	struct geneve_dev *geneve = netdev_priv(dev);
1057 	/* The max_mtu calculation does not take account of GENEVE
1058 	 * options, to avoid excluding potentially valid
1059 	 * configurations.
1060 	 */
1061 	int max_mtu = IP_MAX_MTU - GENEVE_BASE_HLEN - dev->hard_header_len;
1062 
1063 	if (geneve->remote.sa.sa_family == AF_INET6)
1064 		max_mtu -= sizeof(struct ipv6hdr);
1065 	else
1066 		max_mtu -= sizeof(struct iphdr);
1067 
1068 	if (new_mtu < 68)
1069 		return -EINVAL;
1070 
1071 	if (new_mtu > max_mtu) {
1072 		if (strict)
1073 			return -EINVAL;
1074 
1075 		new_mtu = max_mtu;
1076 	}
1077 
1078 	dev->mtu = new_mtu;
1079 	return 0;
1080 }
1081 
1082 static int geneve_change_mtu(struct net_device *dev, int new_mtu)
1083 {
1084 	return __geneve_change_mtu(dev, new_mtu, true);
1085 }
1086 
1087 static int geneve_fill_metadata_dst(struct net_device *dev, struct sk_buff *skb)
1088 {
1089 	struct ip_tunnel_info *info = skb_tunnel_info(skb);
1090 	struct geneve_dev *geneve = netdev_priv(dev);
1091 	struct rtable *rt;
1092 	struct flowi4 fl4;
1093 #if IS_ENABLED(CONFIG_IPV6)
1094 	struct dst_entry *dst;
1095 	struct flowi6 fl6;
1096 #endif
1097 
1098 	if (ip_tunnel_info_af(info) == AF_INET) {
1099 		rt = geneve_get_v4_rt(skb, dev, &fl4, info);
1100 		if (IS_ERR(rt))
1101 			return PTR_ERR(rt);
1102 
1103 		ip_rt_put(rt);
1104 		info->key.u.ipv4.src = fl4.saddr;
1105 #if IS_ENABLED(CONFIG_IPV6)
1106 	} else if (ip_tunnel_info_af(info) == AF_INET6) {
1107 		dst = geneve_get_v6_dst(skb, dev, &fl6, info);
1108 		if (IS_ERR(dst))
1109 			return PTR_ERR(dst);
1110 
1111 		dst_release(dst);
1112 		info->key.u.ipv6.src = fl6.saddr;
1113 #endif
1114 	} else {
1115 		return -EINVAL;
1116 	}
1117 
1118 	info->key.tp_src = udp_flow_src_port(geneve->net, skb,
1119 					     1, USHRT_MAX, true);
1120 	info->key.tp_dst = geneve->dst_port;
1121 	return 0;
1122 }
1123 
1124 static const struct net_device_ops geneve_netdev_ops = {
1125 	.ndo_init		= geneve_init,
1126 	.ndo_uninit		= geneve_uninit,
1127 	.ndo_open		= geneve_open,
1128 	.ndo_stop		= geneve_stop,
1129 	.ndo_start_xmit		= geneve_xmit,
1130 	.ndo_get_stats64	= ip_tunnel_get_stats64,
1131 	.ndo_change_mtu		= geneve_change_mtu,
1132 	.ndo_validate_addr	= eth_validate_addr,
1133 	.ndo_set_mac_address	= eth_mac_addr,
1134 	.ndo_fill_metadata_dst	= geneve_fill_metadata_dst,
1135 };
1136 
1137 static void geneve_get_drvinfo(struct net_device *dev,
1138 			       struct ethtool_drvinfo *drvinfo)
1139 {
1140 	strlcpy(drvinfo->version, GENEVE_NETDEV_VER, sizeof(drvinfo->version));
1141 	strlcpy(drvinfo->driver, "geneve", sizeof(drvinfo->driver));
1142 }
1143 
1144 static const struct ethtool_ops geneve_ethtool_ops = {
1145 	.get_drvinfo	= geneve_get_drvinfo,
1146 	.get_link	= ethtool_op_get_link,
1147 };
1148 
1149 /* Info for udev, that this is a virtual tunnel endpoint */
1150 static struct device_type geneve_type = {
1151 	.name = "geneve",
1152 };
1153 
1154 /* Calls the ndo_udp_tunnel_add of the caller in order to
1155  * supply the listening GENEVE udp ports. Callers are expected
1156  * to implement the ndo_udp_tunnel_add.
1157  */
1158 static void geneve_push_rx_ports(struct net_device *dev)
1159 {
1160 	struct net *net = dev_net(dev);
1161 	struct geneve_net *gn = net_generic(net, geneve_net_id);
1162 	struct geneve_sock *gs;
1163 
1164 	rcu_read_lock();
1165 	list_for_each_entry_rcu(gs, &gn->sock_list, list)
1166 		udp_tunnel_push_rx_port(dev, gs->sock,
1167 					UDP_TUNNEL_TYPE_GENEVE);
1168 	rcu_read_unlock();
1169 }
1170 
1171 /* Initialize the device structure. */
1172 static void geneve_setup(struct net_device *dev)
1173 {
1174 	ether_setup(dev);
1175 
1176 	dev->netdev_ops = &geneve_netdev_ops;
1177 	dev->ethtool_ops = &geneve_ethtool_ops;
1178 	dev->destructor = free_netdev;
1179 
1180 	SET_NETDEV_DEVTYPE(dev, &geneve_type);
1181 
1182 	dev->features    |= NETIF_F_LLTX;
1183 	dev->features    |= NETIF_F_SG | NETIF_F_HW_CSUM;
1184 	dev->features    |= NETIF_F_RXCSUM;
1185 	dev->features    |= NETIF_F_GSO_SOFTWARE;
1186 
1187 	dev->hw_features |= NETIF_F_SG | NETIF_F_HW_CSUM | NETIF_F_RXCSUM;
1188 	dev->hw_features |= NETIF_F_GSO_SOFTWARE;
1189 
1190 	netif_keep_dst(dev);
1191 	dev->priv_flags &= ~IFF_TX_SKB_SHARING;
1192 	dev->priv_flags |= IFF_LIVE_ADDR_CHANGE | IFF_NO_QUEUE;
1193 	eth_hw_addr_random(dev);
1194 }
1195 
1196 static const struct nla_policy geneve_policy[IFLA_GENEVE_MAX + 1] = {
1197 	[IFLA_GENEVE_ID]		= { .type = NLA_U32 },
1198 	[IFLA_GENEVE_REMOTE]		= { .len = FIELD_SIZEOF(struct iphdr, daddr) },
1199 	[IFLA_GENEVE_REMOTE6]		= { .len = sizeof(struct in6_addr) },
1200 	[IFLA_GENEVE_TTL]		= { .type = NLA_U8 },
1201 	[IFLA_GENEVE_TOS]		= { .type = NLA_U8 },
1202 	[IFLA_GENEVE_LABEL]		= { .type = NLA_U32 },
1203 	[IFLA_GENEVE_PORT]		= { .type = NLA_U16 },
1204 	[IFLA_GENEVE_COLLECT_METADATA]	= { .type = NLA_FLAG },
1205 	[IFLA_GENEVE_UDP_CSUM]		= { .type = NLA_U8 },
1206 	[IFLA_GENEVE_UDP_ZERO_CSUM6_TX]	= { .type = NLA_U8 },
1207 	[IFLA_GENEVE_UDP_ZERO_CSUM6_RX]	= { .type = NLA_U8 },
1208 };
1209 
1210 static int geneve_validate(struct nlattr *tb[], struct nlattr *data[])
1211 {
1212 	if (tb[IFLA_ADDRESS]) {
1213 		if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
1214 			return -EINVAL;
1215 
1216 		if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
1217 			return -EADDRNOTAVAIL;
1218 	}
1219 
1220 	if (!data)
1221 		return -EINVAL;
1222 
1223 	if (data[IFLA_GENEVE_ID]) {
1224 		__u32 vni =  nla_get_u32(data[IFLA_GENEVE_ID]);
1225 
1226 		if (vni >= GENEVE_VID_MASK)
1227 			return -ERANGE;
1228 	}
1229 
1230 	return 0;
1231 }
1232 
1233 static struct geneve_dev *geneve_find_dev(struct geneve_net *gn,
1234 					  __be16 dst_port,
1235 					  union geneve_addr *remote,
1236 					  u8 vni[],
1237 					  bool *tun_on_same_port,
1238 					  bool *tun_collect_md)
1239 {
1240 	struct geneve_dev *geneve, *t;
1241 
1242 	*tun_on_same_port = false;
1243 	*tun_collect_md = false;
1244 	t = NULL;
1245 	list_for_each_entry(geneve, &gn->geneve_list, next) {
1246 		if (geneve->dst_port == dst_port) {
1247 			*tun_collect_md = geneve->collect_md;
1248 			*tun_on_same_port = true;
1249 		}
1250 		if (!memcmp(vni, geneve->vni, sizeof(geneve->vni)) &&
1251 		    !memcmp(remote, &geneve->remote, sizeof(geneve->remote)) &&
1252 		    dst_port == geneve->dst_port)
1253 			t = geneve;
1254 	}
1255 	return t;
1256 }
1257 
1258 static int geneve_configure(struct net *net, struct net_device *dev,
1259 			    union geneve_addr *remote,
1260 			    __u32 vni, __u8 ttl, __u8 tos, __be32 label,
1261 			    __be16 dst_port, bool metadata, u32 flags)
1262 {
1263 	struct geneve_net *gn = net_generic(net, geneve_net_id);
1264 	struct geneve_dev *t, *geneve = netdev_priv(dev);
1265 	bool tun_collect_md, tun_on_same_port;
1266 	int err, encap_len;
1267 
1268 	if (!remote)
1269 		return -EINVAL;
1270 	if (metadata &&
1271 	    (remote->sa.sa_family != AF_UNSPEC || vni || tos || ttl || label))
1272 		return -EINVAL;
1273 
1274 	geneve->net = net;
1275 	geneve->dev = dev;
1276 
1277 	geneve->vni[0] = (vni & 0x00ff0000) >> 16;
1278 	geneve->vni[1] = (vni & 0x0000ff00) >> 8;
1279 	geneve->vni[2] =  vni & 0x000000ff;
1280 
1281 	if ((remote->sa.sa_family == AF_INET &&
1282 	     IN_MULTICAST(ntohl(remote->sin.sin_addr.s_addr))) ||
1283 	    (remote->sa.sa_family == AF_INET6 &&
1284 	     ipv6_addr_is_multicast(&remote->sin6.sin6_addr)))
1285 		return -EINVAL;
1286 	if (label && remote->sa.sa_family != AF_INET6)
1287 		return -EINVAL;
1288 
1289 	geneve->remote = *remote;
1290 
1291 	geneve->ttl = ttl;
1292 	geneve->tos = tos;
1293 	geneve->label = label;
1294 	geneve->dst_port = dst_port;
1295 	geneve->collect_md = metadata;
1296 	geneve->flags = flags;
1297 
1298 	t = geneve_find_dev(gn, dst_port, remote, geneve->vni,
1299 			    &tun_on_same_port, &tun_collect_md);
1300 	if (t)
1301 		return -EBUSY;
1302 
1303 	/* make enough headroom for basic scenario */
1304 	encap_len = GENEVE_BASE_HLEN + ETH_HLEN;
1305 	if (remote->sa.sa_family == AF_INET)
1306 		encap_len += sizeof(struct iphdr);
1307 	else
1308 		encap_len += sizeof(struct ipv6hdr);
1309 	dev->needed_headroom = encap_len + ETH_HLEN;
1310 
1311 	if (metadata) {
1312 		if (tun_on_same_port)
1313 			return -EPERM;
1314 	} else {
1315 		if (tun_collect_md)
1316 			return -EPERM;
1317 	}
1318 
1319 	dst_cache_reset(&geneve->dst_cache);
1320 
1321 	err = register_netdevice(dev);
1322 	if (err)
1323 		return err;
1324 
1325 	list_add(&geneve->next, &gn->geneve_list);
1326 	return 0;
1327 }
1328 
1329 static int geneve_newlink(struct net *net, struct net_device *dev,
1330 			  struct nlattr *tb[], struct nlattr *data[])
1331 {
1332 	__be16 dst_port = htons(GENEVE_UDP_PORT);
1333 	__u8 ttl = 0, tos = 0;
1334 	bool metadata = false;
1335 	union geneve_addr remote = geneve_remote_unspec;
1336 	__be32 label = 0;
1337 	__u32 vni = 0;
1338 	u32 flags = 0;
1339 
1340 	if (data[IFLA_GENEVE_REMOTE] && data[IFLA_GENEVE_REMOTE6])
1341 		return -EINVAL;
1342 
1343 	if (data[IFLA_GENEVE_REMOTE]) {
1344 		remote.sa.sa_family = AF_INET;
1345 		remote.sin.sin_addr.s_addr =
1346 			nla_get_in_addr(data[IFLA_GENEVE_REMOTE]);
1347 	}
1348 
1349 	if (data[IFLA_GENEVE_REMOTE6]) {
1350 		if (!IS_ENABLED(CONFIG_IPV6))
1351 			return -EPFNOSUPPORT;
1352 
1353 		remote.sa.sa_family = AF_INET6;
1354 		remote.sin6.sin6_addr =
1355 			nla_get_in6_addr(data[IFLA_GENEVE_REMOTE6]);
1356 
1357 		if (ipv6_addr_type(&remote.sin6.sin6_addr) &
1358 		    IPV6_ADDR_LINKLOCAL) {
1359 			netdev_dbg(dev, "link-local remote is unsupported\n");
1360 			return -EINVAL;
1361 		}
1362 	}
1363 
1364 	if (data[IFLA_GENEVE_ID])
1365 		vni = nla_get_u32(data[IFLA_GENEVE_ID]);
1366 
1367 	if (data[IFLA_GENEVE_TTL])
1368 		ttl = nla_get_u8(data[IFLA_GENEVE_TTL]);
1369 
1370 	if (data[IFLA_GENEVE_TOS])
1371 		tos = nla_get_u8(data[IFLA_GENEVE_TOS]);
1372 
1373 	if (data[IFLA_GENEVE_LABEL])
1374 		label = nla_get_be32(data[IFLA_GENEVE_LABEL]) &
1375 			IPV6_FLOWLABEL_MASK;
1376 
1377 	if (data[IFLA_GENEVE_PORT])
1378 		dst_port = nla_get_be16(data[IFLA_GENEVE_PORT]);
1379 
1380 	if (data[IFLA_GENEVE_COLLECT_METADATA])
1381 		metadata = true;
1382 
1383 	if (data[IFLA_GENEVE_UDP_CSUM] &&
1384 	    !nla_get_u8(data[IFLA_GENEVE_UDP_CSUM]))
1385 		flags |= GENEVE_F_UDP_ZERO_CSUM_TX;
1386 
1387 	if (data[IFLA_GENEVE_UDP_ZERO_CSUM6_TX] &&
1388 	    nla_get_u8(data[IFLA_GENEVE_UDP_ZERO_CSUM6_TX]))
1389 		flags |= GENEVE_F_UDP_ZERO_CSUM6_TX;
1390 
1391 	if (data[IFLA_GENEVE_UDP_ZERO_CSUM6_RX] &&
1392 	    nla_get_u8(data[IFLA_GENEVE_UDP_ZERO_CSUM6_RX]))
1393 		flags |= GENEVE_F_UDP_ZERO_CSUM6_RX;
1394 
1395 	return geneve_configure(net, dev, &remote, vni, ttl, tos, label,
1396 				dst_port, metadata, flags);
1397 }
1398 
1399 static void geneve_dellink(struct net_device *dev, struct list_head *head)
1400 {
1401 	struct geneve_dev *geneve = netdev_priv(dev);
1402 
1403 	list_del(&geneve->next);
1404 	unregister_netdevice_queue(dev, head);
1405 }
1406 
1407 static size_t geneve_get_size(const struct net_device *dev)
1408 {
1409 	return nla_total_size(sizeof(__u32)) +	/* IFLA_GENEVE_ID */
1410 		nla_total_size(sizeof(struct in6_addr)) + /* IFLA_GENEVE_REMOTE{6} */
1411 		nla_total_size(sizeof(__u8)) +  /* IFLA_GENEVE_TTL */
1412 		nla_total_size(sizeof(__u8)) +  /* IFLA_GENEVE_TOS */
1413 		nla_total_size(sizeof(__be32)) +  /* IFLA_GENEVE_LABEL */
1414 		nla_total_size(sizeof(__be16)) +  /* IFLA_GENEVE_PORT */
1415 		nla_total_size(0) +	 /* IFLA_GENEVE_COLLECT_METADATA */
1416 		nla_total_size(sizeof(__u8)) + /* IFLA_GENEVE_UDP_CSUM */
1417 		nla_total_size(sizeof(__u8)) + /* IFLA_GENEVE_UDP_ZERO_CSUM6_TX */
1418 		nla_total_size(sizeof(__u8)) + /* IFLA_GENEVE_UDP_ZERO_CSUM6_RX */
1419 		0;
1420 }
1421 
1422 static int geneve_fill_info(struct sk_buff *skb, const struct net_device *dev)
1423 {
1424 	struct geneve_dev *geneve = netdev_priv(dev);
1425 	__u32 vni;
1426 
1427 	vni = (geneve->vni[0] << 16) | (geneve->vni[1] << 8) | geneve->vni[2];
1428 	if (nla_put_u32(skb, IFLA_GENEVE_ID, vni))
1429 		goto nla_put_failure;
1430 
1431 	if (geneve->remote.sa.sa_family == AF_INET) {
1432 		if (nla_put_in_addr(skb, IFLA_GENEVE_REMOTE,
1433 				    geneve->remote.sin.sin_addr.s_addr))
1434 			goto nla_put_failure;
1435 #if IS_ENABLED(CONFIG_IPV6)
1436 	} else {
1437 		if (nla_put_in6_addr(skb, IFLA_GENEVE_REMOTE6,
1438 				     &geneve->remote.sin6.sin6_addr))
1439 			goto nla_put_failure;
1440 #endif
1441 	}
1442 
1443 	if (nla_put_u8(skb, IFLA_GENEVE_TTL, geneve->ttl) ||
1444 	    nla_put_u8(skb, IFLA_GENEVE_TOS, geneve->tos) ||
1445 	    nla_put_be32(skb, IFLA_GENEVE_LABEL, geneve->label))
1446 		goto nla_put_failure;
1447 
1448 	if (nla_put_be16(skb, IFLA_GENEVE_PORT, geneve->dst_port))
1449 		goto nla_put_failure;
1450 
1451 	if (geneve->collect_md) {
1452 		if (nla_put_flag(skb, IFLA_GENEVE_COLLECT_METADATA))
1453 			goto nla_put_failure;
1454 	}
1455 
1456 	if (nla_put_u8(skb, IFLA_GENEVE_UDP_CSUM,
1457 		       !(geneve->flags & GENEVE_F_UDP_ZERO_CSUM_TX)) ||
1458 	    nla_put_u8(skb, IFLA_GENEVE_UDP_ZERO_CSUM6_TX,
1459 		       !!(geneve->flags & GENEVE_F_UDP_ZERO_CSUM6_TX)) ||
1460 	    nla_put_u8(skb, IFLA_GENEVE_UDP_ZERO_CSUM6_RX,
1461 		       !!(geneve->flags & GENEVE_F_UDP_ZERO_CSUM6_RX)))
1462 		goto nla_put_failure;
1463 
1464 	return 0;
1465 
1466 nla_put_failure:
1467 	return -EMSGSIZE;
1468 }
1469 
1470 static struct rtnl_link_ops geneve_link_ops __read_mostly = {
1471 	.kind		= "geneve",
1472 	.maxtype	= IFLA_GENEVE_MAX,
1473 	.policy		= geneve_policy,
1474 	.priv_size	= sizeof(struct geneve_dev),
1475 	.setup		= geneve_setup,
1476 	.validate	= geneve_validate,
1477 	.newlink	= geneve_newlink,
1478 	.dellink	= geneve_dellink,
1479 	.get_size	= geneve_get_size,
1480 	.fill_info	= geneve_fill_info,
1481 };
1482 
1483 struct net_device *geneve_dev_create_fb(struct net *net, const char *name,
1484 					u8 name_assign_type, u16 dst_port)
1485 {
1486 	struct nlattr *tb[IFLA_MAX + 1];
1487 	struct net_device *dev;
1488 	LIST_HEAD(list_kill);
1489 	int err;
1490 
1491 	memset(tb, 0, sizeof(tb));
1492 	dev = rtnl_create_link(net, name, name_assign_type,
1493 			       &geneve_link_ops, tb);
1494 	if (IS_ERR(dev))
1495 		return dev;
1496 
1497 	err = geneve_configure(net, dev, &geneve_remote_unspec,
1498 			       0, 0, 0, 0, htons(dst_port), true,
1499 			       GENEVE_F_UDP_ZERO_CSUM6_RX);
1500 	if (err) {
1501 		free_netdev(dev);
1502 		return ERR_PTR(err);
1503 	}
1504 
1505 	/* openvswitch users expect packet sizes to be unrestricted,
1506 	 * so set the largest MTU we can.
1507 	 */
1508 	err = __geneve_change_mtu(dev, IP_MAX_MTU, false);
1509 	if (err)
1510 		goto err;
1511 
1512 	err = rtnl_configure_link(dev, NULL);
1513 	if (err < 0)
1514 		goto err;
1515 
1516 	return dev;
1517 
1518  err:
1519 	geneve_dellink(dev, &list_kill);
1520 	unregister_netdevice_many(&list_kill);
1521 	return ERR_PTR(err);
1522 }
1523 EXPORT_SYMBOL_GPL(geneve_dev_create_fb);
1524 
1525 static int geneve_netdevice_event(struct notifier_block *unused,
1526 				  unsigned long event, void *ptr)
1527 {
1528 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
1529 
1530 	if (event == NETDEV_UDP_TUNNEL_PUSH_INFO)
1531 		geneve_push_rx_ports(dev);
1532 
1533 	return NOTIFY_DONE;
1534 }
1535 
1536 static struct notifier_block geneve_notifier_block __read_mostly = {
1537 	.notifier_call = geneve_netdevice_event,
1538 };
1539 
1540 static __net_init int geneve_init_net(struct net *net)
1541 {
1542 	struct geneve_net *gn = net_generic(net, geneve_net_id);
1543 
1544 	INIT_LIST_HEAD(&gn->geneve_list);
1545 	INIT_LIST_HEAD(&gn->sock_list);
1546 	return 0;
1547 }
1548 
1549 static void __net_exit geneve_exit_net(struct net *net)
1550 {
1551 	struct geneve_net *gn = net_generic(net, geneve_net_id);
1552 	struct geneve_dev *geneve, *next;
1553 	struct net_device *dev, *aux;
1554 	LIST_HEAD(list);
1555 
1556 	rtnl_lock();
1557 
1558 	/* gather any geneve devices that were moved into this ns */
1559 	for_each_netdev_safe(net, dev, aux)
1560 		if (dev->rtnl_link_ops == &geneve_link_ops)
1561 			unregister_netdevice_queue(dev, &list);
1562 
1563 	/* now gather any other geneve devices that were created in this ns */
1564 	list_for_each_entry_safe(geneve, next, &gn->geneve_list, next) {
1565 		/* If geneve->dev is in the same netns, it was already added
1566 		 * to the list by the previous loop.
1567 		 */
1568 		if (!net_eq(dev_net(geneve->dev), net))
1569 			unregister_netdevice_queue(geneve->dev, &list);
1570 	}
1571 
1572 	/* unregister the devices gathered above */
1573 	unregister_netdevice_many(&list);
1574 	rtnl_unlock();
1575 }
1576 
1577 static struct pernet_operations geneve_net_ops = {
1578 	.init = geneve_init_net,
1579 	.exit = geneve_exit_net,
1580 	.id   = &geneve_net_id,
1581 	.size = sizeof(struct geneve_net),
1582 };
1583 
1584 static int __init geneve_init_module(void)
1585 {
1586 	int rc;
1587 
1588 	rc = register_pernet_subsys(&geneve_net_ops);
1589 	if (rc)
1590 		goto out1;
1591 
1592 	rc = register_netdevice_notifier(&geneve_notifier_block);
1593 	if (rc)
1594 		goto out2;
1595 
1596 	rc = rtnl_link_register(&geneve_link_ops);
1597 	if (rc)
1598 		goto out3;
1599 
1600 	return 0;
1601 
1602 out3:
1603 	unregister_netdevice_notifier(&geneve_notifier_block);
1604 out2:
1605 	unregister_pernet_subsys(&geneve_net_ops);
1606 out1:
1607 	return rc;
1608 }
1609 late_initcall(geneve_init_module);
1610 
1611 static void __exit geneve_cleanup_module(void)
1612 {
1613 	rtnl_link_unregister(&geneve_link_ops);
1614 	unregister_netdevice_notifier(&geneve_notifier_block);
1615 	unregister_pernet_subsys(&geneve_net_ops);
1616 }
1617 module_exit(geneve_cleanup_module);
1618 
1619 MODULE_LICENSE("GPL");
1620 MODULE_VERSION(GENEVE_NETDEV_VER);
1621 MODULE_AUTHOR("John W. Linville <linville@tuxdriver.com>");
1622 MODULE_DESCRIPTION("Interface driver for GENEVE encapsulated traffic");
1623 MODULE_ALIAS_RTNL_LINK("geneve");
1624