xref: /openbmc/linux/drivers/net/geneve.c (revision 7f9562a1f405306eacb97f95d78cb996e33f27f5)
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/netdevice.h>
16 #include <linux/etherdevice.h>
17 #include <linux/hash.h>
18 #include <net/dst_metadata.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 /* Pseudo network device */
49 struct geneve_dev {
50 	struct hlist_node  hlist;	/* vni hash table */
51 	struct net	   *net;	/* netns for packet i/o */
52 	struct net_device  *dev;	/* netdev for geneve tunnel */
53 	struct geneve_sock *sock;	/* socket used for geneve tunnel */
54 	u8                 vni[3];	/* virtual network ID for tunnel */
55 	u8                 ttl;		/* TTL override */
56 	u8                 tos;		/* TOS override */
57 	struct sockaddr_in remote;	/* IPv4 address for link partner */
58 	struct list_head   next;	/* geneve's per namespace list */
59 	__be16		   dst_port;
60 	bool		   collect_md;
61 };
62 
63 struct geneve_sock {
64 	bool			collect_md;
65 	struct list_head	list;
66 	struct socket		*sock;
67 	struct rcu_head		rcu;
68 	int			refcnt;
69 	struct udp_offload	udp_offloads;
70 	struct hlist_head	vni_list[VNI_HASH_SIZE];
71 };
72 
73 static inline __u32 geneve_net_vni_hash(u8 vni[3])
74 {
75 	__u32 vnid;
76 
77 	vnid = (vni[0] << 16) | (vni[1] << 8) | vni[2];
78 	return hash_32(vnid, VNI_HASH_BITS);
79 }
80 
81 static __be64 vni_to_tunnel_id(const __u8 *vni)
82 {
83 #ifdef __BIG_ENDIAN
84 	return (vni[0] << 16) | (vni[1] << 8) | vni[2];
85 #else
86 	return (__force __be64)(((__force u64)vni[0] << 40) |
87 				((__force u64)vni[1] << 48) |
88 				((__force u64)vni[2] << 56));
89 #endif
90 }
91 
92 static struct geneve_dev *geneve_lookup(struct geneve_sock *gs,
93 					__be32 addr, u8 vni[])
94 {
95 	struct hlist_head *vni_list_head;
96 	struct geneve_dev *geneve;
97 	__u32 hash;
98 
99 	/* Find the device for this VNI */
100 	hash = geneve_net_vni_hash(vni);
101 	vni_list_head = &gs->vni_list[hash];
102 	hlist_for_each_entry_rcu(geneve, vni_list_head, hlist) {
103 		if (!memcmp(vni, geneve->vni, sizeof(geneve->vni)) &&
104 		    addr == geneve->remote.sin_addr.s_addr)
105 			return geneve;
106 	}
107 	return NULL;
108 }
109 
110 static inline struct genevehdr *geneve_hdr(const struct sk_buff *skb)
111 {
112 	return (struct genevehdr *)(udp_hdr(skb) + 1);
113 }
114 
115 /* geneve receive/decap routine */
116 static void geneve_rx(struct geneve_sock *gs, struct sk_buff *skb)
117 {
118 	struct genevehdr *gnvh = geneve_hdr(skb);
119 	struct metadata_dst *tun_dst = NULL;
120 	struct geneve_dev *geneve = NULL;
121 	struct pcpu_sw_netstats *stats;
122 	struct iphdr *iph;
123 	u8 *vni;
124 	__be32 addr;
125 	int err;
126 
127 	if (gs->collect_md) {
128 		static u8 zero_vni[3];
129 
130 		vni = zero_vni;
131 		addr = 0;
132 	} else {
133 		vni = gnvh->vni;
134 		iph = ip_hdr(skb); /* Still outer IP header... */
135 		addr = iph->saddr;
136 	}
137 
138 	geneve = geneve_lookup(gs, addr, vni);
139 	if (!geneve)
140 		goto drop;
141 
142 	if (ip_tunnel_collect_metadata() || gs->collect_md) {
143 		__be16 flags;
144 		void *opts;
145 
146 		flags = TUNNEL_KEY | TUNNEL_GENEVE_OPT |
147 			(gnvh->oam ? TUNNEL_OAM : 0) |
148 			(gnvh->critical ? TUNNEL_CRIT_OPT : 0);
149 
150 		tun_dst = udp_tun_rx_dst(skb, AF_INET, flags,
151 					 vni_to_tunnel_id(gnvh->vni),
152 					 gnvh->opt_len * 4);
153 		if (!tun_dst)
154 			goto drop;
155 
156 		/* Update tunnel dst according to Geneve options. */
157 		opts = ip_tunnel_info_opts(&tun_dst->u.tun_info,
158 					   gnvh->opt_len * 4);
159 		memcpy(opts, gnvh->options, gnvh->opt_len * 4);
160 	} else {
161 		/* Drop packets w/ critical options,
162 		 * since we don't support any...
163 		 */
164 		if (gnvh->critical)
165 			goto drop;
166 	}
167 
168 	skb_reset_mac_header(skb);
169 	skb_scrub_packet(skb, !net_eq(geneve->net, dev_net(geneve->dev)));
170 	skb->protocol = eth_type_trans(skb, geneve->dev);
171 	skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN);
172 
173 	if (tun_dst)
174 		skb_dst_set(skb, &tun_dst->dst);
175 
176 	/* Ignore packet loops (and multicast echo) */
177 	if (ether_addr_equal(eth_hdr(skb)->h_source, geneve->dev->dev_addr))
178 		goto drop;
179 
180 	skb_reset_network_header(skb);
181 
182 	iph = ip_hdr(skb); /* Now inner IP header... */
183 	err = IP_ECN_decapsulate(iph, skb);
184 
185 	if (unlikely(err)) {
186 		if (log_ecn_error)
187 			net_info_ratelimited("non-ECT from %pI4 with TOS=%#x\n",
188 					     &iph->saddr, iph->tos);
189 		if (err > 1) {
190 			++geneve->dev->stats.rx_frame_errors;
191 			++geneve->dev->stats.rx_errors;
192 			goto drop;
193 		}
194 	}
195 
196 	stats = this_cpu_ptr(geneve->dev->tstats);
197 	u64_stats_update_begin(&stats->syncp);
198 	stats->rx_packets++;
199 	stats->rx_bytes += skb->len;
200 	u64_stats_update_end(&stats->syncp);
201 
202 	netif_rx(skb);
203 	return;
204 drop:
205 	/* Consume bad packet */
206 	kfree_skb(skb);
207 }
208 
209 /* Setup stats when device is created */
210 static int geneve_init(struct net_device *dev)
211 {
212 	dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
213 	if (!dev->tstats)
214 		return -ENOMEM;
215 	return 0;
216 }
217 
218 static void geneve_uninit(struct net_device *dev)
219 {
220 	free_percpu(dev->tstats);
221 }
222 
223 /* Callback from net/ipv4/udp.c to receive packets */
224 static int geneve_udp_encap_recv(struct sock *sk, struct sk_buff *skb)
225 {
226 	struct genevehdr *geneveh;
227 	struct geneve_sock *gs;
228 	int opts_len;
229 
230 	/* Need Geneve and inner Ethernet header to be present */
231 	if (unlikely(!pskb_may_pull(skb, GENEVE_BASE_HLEN)))
232 		goto error;
233 
234 	/* Return packets with reserved bits set */
235 	geneveh = geneve_hdr(skb);
236 	if (unlikely(geneveh->ver != GENEVE_VER))
237 		goto error;
238 
239 	if (unlikely(geneveh->proto_type != htons(ETH_P_TEB)))
240 		goto error;
241 
242 	opts_len = geneveh->opt_len * 4;
243 	if (iptunnel_pull_header(skb, GENEVE_BASE_HLEN + opts_len,
244 				 htons(ETH_P_TEB)))
245 		goto drop;
246 
247 	gs = rcu_dereference_sk_user_data(sk);
248 	if (!gs)
249 		goto drop;
250 
251 	geneve_rx(gs, skb);
252 	return 0;
253 
254 drop:
255 	/* Consume bad packet */
256 	kfree_skb(skb);
257 	return 0;
258 
259 error:
260 	/* Let the UDP layer deal with the skb */
261 	return 1;
262 }
263 
264 static struct socket *geneve_create_sock(struct net *net, bool ipv6,
265 					 __be16 port)
266 {
267 	struct socket *sock;
268 	struct udp_port_cfg udp_conf;
269 	int err;
270 
271 	memset(&udp_conf, 0, sizeof(udp_conf));
272 
273 	if (ipv6) {
274 		udp_conf.family = AF_INET6;
275 	} else {
276 		udp_conf.family = AF_INET;
277 		udp_conf.local_ip.s_addr = htonl(INADDR_ANY);
278 	}
279 
280 	udp_conf.local_udp_port = port;
281 
282 	/* Open UDP socket */
283 	err = udp_sock_create(net, &udp_conf, &sock);
284 	if (err < 0)
285 		return ERR_PTR(err);
286 
287 	return sock;
288 }
289 
290 static void geneve_notify_add_rx_port(struct geneve_sock *gs)
291 {
292 	struct sock *sk = gs->sock->sk;
293 	sa_family_t sa_family = sk->sk_family;
294 	int err;
295 
296 	if (sa_family == AF_INET) {
297 		err = udp_add_offload(&gs->udp_offloads);
298 		if (err)
299 			pr_warn("geneve: udp_add_offload failed with status %d\n",
300 				err);
301 	}
302 }
303 
304 static int geneve_hlen(struct genevehdr *gh)
305 {
306 	return sizeof(*gh) + gh->opt_len * 4;
307 }
308 
309 static struct sk_buff **geneve_gro_receive(struct sk_buff **head,
310 					   struct sk_buff *skb,
311 					   struct udp_offload *uoff)
312 {
313 	struct sk_buff *p, **pp = NULL;
314 	struct genevehdr *gh, *gh2;
315 	unsigned int hlen, gh_len, off_gnv;
316 	const struct packet_offload *ptype;
317 	__be16 type;
318 	int flush = 1;
319 
320 	off_gnv = skb_gro_offset(skb);
321 	hlen = off_gnv + sizeof(*gh);
322 	gh = skb_gro_header_fast(skb, off_gnv);
323 	if (skb_gro_header_hard(skb, hlen)) {
324 		gh = skb_gro_header_slow(skb, hlen, off_gnv);
325 		if (unlikely(!gh))
326 			goto out;
327 	}
328 
329 	if (gh->ver != GENEVE_VER || gh->oam)
330 		goto out;
331 	gh_len = geneve_hlen(gh);
332 
333 	hlen = off_gnv + gh_len;
334 	if (skb_gro_header_hard(skb, hlen)) {
335 		gh = skb_gro_header_slow(skb, hlen, off_gnv);
336 		if (unlikely(!gh))
337 			goto out;
338 	}
339 
340 	flush = 0;
341 
342 	for (p = *head; p; p = p->next) {
343 		if (!NAPI_GRO_CB(p)->same_flow)
344 			continue;
345 
346 		gh2 = (struct genevehdr *)(p->data + off_gnv);
347 		if (gh->opt_len != gh2->opt_len ||
348 		    memcmp(gh, gh2, gh_len)) {
349 			NAPI_GRO_CB(p)->same_flow = 0;
350 			continue;
351 		}
352 	}
353 
354 	type = gh->proto_type;
355 
356 	rcu_read_lock();
357 	ptype = gro_find_receive_by_type(type);
358 	if (!ptype) {
359 		flush = 1;
360 		goto out_unlock;
361 	}
362 
363 	skb_gro_pull(skb, gh_len);
364 	skb_gro_postpull_rcsum(skb, gh, gh_len);
365 	pp = ptype->callbacks.gro_receive(head, skb);
366 
367 out_unlock:
368 	rcu_read_unlock();
369 out:
370 	NAPI_GRO_CB(skb)->flush |= flush;
371 
372 	return pp;
373 }
374 
375 static int geneve_gro_complete(struct sk_buff *skb, int nhoff,
376 			       struct udp_offload *uoff)
377 {
378 	struct genevehdr *gh;
379 	struct packet_offload *ptype;
380 	__be16 type;
381 	int gh_len;
382 	int err = -ENOSYS;
383 
384 	udp_tunnel_gro_complete(skb, nhoff);
385 
386 	gh = (struct genevehdr *)(skb->data + nhoff);
387 	gh_len = geneve_hlen(gh);
388 	type = gh->proto_type;
389 
390 	rcu_read_lock();
391 	ptype = gro_find_complete_by_type(type);
392 	if (ptype)
393 		err = ptype->callbacks.gro_complete(skb, nhoff + gh_len);
394 
395 	rcu_read_unlock();
396 	return err;
397 }
398 
399 /* Create new listen socket if needed */
400 static struct geneve_sock *geneve_socket_create(struct net *net, __be16 port,
401 						bool ipv6)
402 {
403 	struct geneve_net *gn = net_generic(net, geneve_net_id);
404 	struct geneve_sock *gs;
405 	struct socket *sock;
406 	struct udp_tunnel_sock_cfg tunnel_cfg;
407 	int h;
408 
409 	gs = kzalloc(sizeof(*gs), GFP_KERNEL);
410 	if (!gs)
411 		return ERR_PTR(-ENOMEM);
412 
413 	sock = geneve_create_sock(net, ipv6, port);
414 	if (IS_ERR(sock)) {
415 		kfree(gs);
416 		return ERR_CAST(sock);
417 	}
418 
419 	gs->sock = sock;
420 	gs->refcnt = 1;
421 	for (h = 0; h < VNI_HASH_SIZE; ++h)
422 		INIT_HLIST_HEAD(&gs->vni_list[h]);
423 
424 	/* Initialize the geneve udp offloads structure */
425 	gs->udp_offloads.port = port;
426 	gs->udp_offloads.callbacks.gro_receive  = geneve_gro_receive;
427 	gs->udp_offloads.callbacks.gro_complete = geneve_gro_complete;
428 	geneve_notify_add_rx_port(gs);
429 
430 	/* Mark socket as an encapsulation socket */
431 	tunnel_cfg.sk_user_data = gs;
432 	tunnel_cfg.encap_type = 1;
433 	tunnel_cfg.encap_rcv = geneve_udp_encap_recv;
434 	tunnel_cfg.encap_destroy = NULL;
435 	setup_udp_tunnel_sock(net, sock, &tunnel_cfg);
436 	list_add(&gs->list, &gn->sock_list);
437 	return gs;
438 }
439 
440 static void geneve_notify_del_rx_port(struct geneve_sock *gs)
441 {
442 	struct sock *sk = gs->sock->sk;
443 	sa_family_t sa_family = sk->sk_family;
444 
445 	if (sa_family == AF_INET)
446 		udp_del_offload(&gs->udp_offloads);
447 }
448 
449 static void geneve_sock_release(struct geneve_sock *gs)
450 {
451 	if (--gs->refcnt)
452 		return;
453 
454 	list_del(&gs->list);
455 	geneve_notify_del_rx_port(gs);
456 	udp_tunnel_sock_release(gs->sock);
457 	kfree_rcu(gs, rcu);
458 }
459 
460 static struct geneve_sock *geneve_find_sock(struct geneve_net *gn,
461 					    __be16 dst_port)
462 {
463 	struct geneve_sock *gs;
464 
465 	list_for_each_entry(gs, &gn->sock_list, list) {
466 		if (inet_sk(gs->sock->sk)->inet_sport == dst_port &&
467 		    inet_sk(gs->sock->sk)->sk.sk_family == AF_INET) {
468 			return gs;
469 		}
470 	}
471 	return NULL;
472 }
473 
474 static int geneve_open(struct net_device *dev)
475 {
476 	struct geneve_dev *geneve = netdev_priv(dev);
477 	struct net *net = geneve->net;
478 	struct geneve_net *gn = net_generic(net, geneve_net_id);
479 	struct geneve_sock *gs;
480 	__u32 hash;
481 
482 	gs = geneve_find_sock(gn, geneve->dst_port);
483 	if (gs) {
484 		gs->refcnt++;
485 		goto out;
486 	}
487 
488 	gs = geneve_socket_create(net, geneve->dst_port, false);
489 	if (IS_ERR(gs))
490 		return PTR_ERR(gs);
491 
492 out:
493 	gs->collect_md = geneve->collect_md;
494 	geneve->sock = gs;
495 
496 	hash = geneve_net_vni_hash(geneve->vni);
497 	hlist_add_head_rcu(&geneve->hlist, &gs->vni_list[hash]);
498 	return 0;
499 }
500 
501 static int geneve_stop(struct net_device *dev)
502 {
503 	struct geneve_dev *geneve = netdev_priv(dev);
504 	struct geneve_sock *gs = geneve->sock;
505 
506 	if (!hlist_unhashed(&geneve->hlist))
507 		hlist_del_rcu(&geneve->hlist);
508 	geneve_sock_release(gs);
509 	return 0;
510 }
511 
512 static int geneve_build_skb(struct rtable *rt, struct sk_buff *skb,
513 			    __be16 tun_flags, u8 vni[3], u8 opt_len, u8 *opt,
514 			    bool csum)
515 {
516 	struct genevehdr *gnvh;
517 	int min_headroom;
518 	int err;
519 
520 	min_headroom = LL_RESERVED_SPACE(rt->dst.dev) + rt->dst.header_len
521 			+ GENEVE_BASE_HLEN + opt_len + sizeof(struct iphdr);
522 	err = skb_cow_head(skb, min_headroom);
523 	if (unlikely(err)) {
524 		kfree_skb(skb);
525 		goto free_rt;
526 	}
527 
528 	skb = udp_tunnel_handle_offloads(skb, csum);
529 	if (IS_ERR(skb)) {
530 		err = PTR_ERR(skb);
531 		goto free_rt;
532 	}
533 
534 	gnvh = (struct genevehdr *)__skb_push(skb, sizeof(*gnvh) + opt_len);
535 	gnvh->ver = GENEVE_VER;
536 	gnvh->opt_len = opt_len / 4;
537 	gnvh->oam = !!(tun_flags & TUNNEL_OAM);
538 	gnvh->critical = !!(tun_flags & TUNNEL_CRIT_OPT);
539 	gnvh->rsvd1 = 0;
540 	memcpy(gnvh->vni, vni, 3);
541 	gnvh->proto_type = htons(ETH_P_TEB);
542 	gnvh->rsvd2 = 0;
543 	memcpy(gnvh->options, opt, opt_len);
544 
545 	skb_set_inner_protocol(skb, htons(ETH_P_TEB));
546 	return 0;
547 
548 free_rt:
549 	ip_rt_put(rt);
550 	return err;
551 }
552 
553 static struct rtable *geneve_get_rt(struct sk_buff *skb,
554 				    struct net_device *dev,
555 				    struct flowi4 *fl4,
556 				    struct ip_tunnel_info *info)
557 {
558 	struct geneve_dev *geneve = netdev_priv(dev);
559 	struct rtable *rt = NULL;
560 	__u8 tos;
561 
562 	memset(fl4, 0, sizeof(*fl4));
563 	fl4->flowi4_mark = skb->mark;
564 	fl4->flowi4_proto = IPPROTO_UDP;
565 
566 	if (info) {
567 		fl4->daddr = info->key.u.ipv4.dst;
568 		fl4->saddr = info->key.u.ipv4.src;
569 		fl4->flowi4_tos = RT_TOS(info->key.tos);
570 	} else {
571 		tos = geneve->tos;
572 		if (tos == 1) {
573 			const struct iphdr *iip = ip_hdr(skb);
574 
575 			tos = ip_tunnel_get_dsfield(iip, skb);
576 		}
577 
578 		fl4->flowi4_tos = RT_TOS(tos);
579 		fl4->daddr = geneve->remote.sin_addr.s_addr;
580 	}
581 
582 	rt = ip_route_output_key(geneve->net, fl4);
583 	if (IS_ERR(rt)) {
584 		netdev_dbg(dev, "no route to %pI4\n", &fl4->daddr);
585 		dev->stats.tx_carrier_errors++;
586 		return rt;
587 	}
588 	if (rt->dst.dev == dev) { /* is this necessary? */
589 		netdev_dbg(dev, "circular route to %pI4\n", &fl4->daddr);
590 		dev->stats.collisions++;
591 		ip_rt_put(rt);
592 		return ERR_PTR(-EINVAL);
593 	}
594 	return rt;
595 }
596 
597 /* Convert 64 bit tunnel ID to 24 bit VNI. */
598 static void tunnel_id_to_vni(__be64 tun_id, __u8 *vni)
599 {
600 #ifdef __BIG_ENDIAN
601 	vni[0] = (__force __u8)(tun_id >> 16);
602 	vni[1] = (__force __u8)(tun_id >> 8);
603 	vni[2] = (__force __u8)tun_id;
604 #else
605 	vni[0] = (__force __u8)((__force u64)tun_id >> 40);
606 	vni[1] = (__force __u8)((__force u64)tun_id >> 48);
607 	vni[2] = (__force __u8)((__force u64)tun_id >> 56);
608 #endif
609 }
610 
611 static netdev_tx_t geneve_xmit(struct sk_buff *skb, struct net_device *dev)
612 {
613 	struct geneve_dev *geneve = netdev_priv(dev);
614 	struct geneve_sock *gs = geneve->sock;
615 	struct ip_tunnel_info *info = NULL;
616 	struct rtable *rt = NULL;
617 	struct flowi4 fl4;
618 	__u8 tos, ttl;
619 	__be16 sport;
620 	bool udp_csum;
621 	__be16 df;
622 	int err;
623 
624 	if (geneve->collect_md) {
625 		info = skb_tunnel_info(skb);
626 		if (unlikely(info && !(info->mode & IP_TUNNEL_INFO_TX))) {
627 			netdev_dbg(dev, "no tunnel metadata\n");
628 			goto tx_error;
629 		}
630 		if (info && ip_tunnel_info_af(info) != AF_INET)
631 			goto tx_error;
632 	}
633 
634 	rt = geneve_get_rt(skb, dev, &fl4, info);
635 	if (IS_ERR(rt)) {
636 		netdev_dbg(dev, "no route to %pI4\n", &fl4.daddr);
637 		dev->stats.tx_carrier_errors++;
638 		goto tx_error;
639 	}
640 
641 	sport = udp_flow_src_port(geneve->net, skb, 1, USHRT_MAX, true);
642 	skb_reset_mac_header(skb);
643 
644 	if (info) {
645 		const struct ip_tunnel_key *key = &info->key;
646 		u8 *opts = NULL;
647 		u8 vni[3];
648 
649 		tunnel_id_to_vni(key->tun_id, vni);
650 		if (key->tun_flags & TUNNEL_GENEVE_OPT)
651 			opts = ip_tunnel_info_opts(info, info->options_len);
652 
653 		udp_csum = !!(key->tun_flags & TUNNEL_CSUM);
654 		err = geneve_build_skb(rt, skb, key->tun_flags, vni,
655 				       info->options_len, opts, udp_csum);
656 		if (unlikely(err))
657 			goto err;
658 
659 		tos = key->tos;
660 		ttl = key->ttl;
661 		df = key->tun_flags & TUNNEL_DONT_FRAGMENT ? htons(IP_DF) : 0;
662 	} else {
663 		const struct iphdr *iip; /* interior IP header */
664 
665 		udp_csum = false;
666 		err = geneve_build_skb(rt, skb, 0, geneve->vni,
667 				       0, NULL, udp_csum);
668 		if (unlikely(err))
669 			goto err;
670 
671 		iip = ip_hdr(skb);
672 		tos = ip_tunnel_ecn_encap(fl4.flowi4_tos, iip, skb);
673 		ttl = geneve->ttl;
674 		if (!ttl && IN_MULTICAST(ntohl(fl4.daddr)))
675 			ttl = 1;
676 		ttl = ttl ? : ip4_dst_hoplimit(&rt->dst);
677 		df = 0;
678 	}
679 	err = udp_tunnel_xmit_skb(rt, gs->sock->sk, skb, fl4.saddr, fl4.daddr,
680 				  tos, ttl, df, sport, geneve->dst_port,
681 				  !net_eq(geneve->net, dev_net(geneve->dev)),
682 				  !udp_csum);
683 
684 	iptunnel_xmit_stats(err, &dev->stats, dev->tstats);
685 	return NETDEV_TX_OK;
686 
687 tx_error:
688 	dev_kfree_skb(skb);
689 err:
690 	dev->stats.tx_errors++;
691 	return NETDEV_TX_OK;
692 }
693 
694 static const struct net_device_ops geneve_netdev_ops = {
695 	.ndo_init		= geneve_init,
696 	.ndo_uninit		= geneve_uninit,
697 	.ndo_open		= geneve_open,
698 	.ndo_stop		= geneve_stop,
699 	.ndo_start_xmit		= geneve_xmit,
700 	.ndo_get_stats64	= ip_tunnel_get_stats64,
701 	.ndo_change_mtu		= eth_change_mtu,
702 	.ndo_validate_addr	= eth_validate_addr,
703 	.ndo_set_mac_address	= eth_mac_addr,
704 };
705 
706 static void geneve_get_drvinfo(struct net_device *dev,
707 			       struct ethtool_drvinfo *drvinfo)
708 {
709 	strlcpy(drvinfo->version, GENEVE_NETDEV_VER, sizeof(drvinfo->version));
710 	strlcpy(drvinfo->driver, "geneve", sizeof(drvinfo->driver));
711 }
712 
713 static const struct ethtool_ops geneve_ethtool_ops = {
714 	.get_drvinfo	= geneve_get_drvinfo,
715 	.get_link	= ethtool_op_get_link,
716 };
717 
718 /* Info for udev, that this is a virtual tunnel endpoint */
719 static struct device_type geneve_type = {
720 	.name = "geneve",
721 };
722 
723 /* Initialize the device structure. */
724 static void geneve_setup(struct net_device *dev)
725 {
726 	ether_setup(dev);
727 
728 	dev->netdev_ops = &geneve_netdev_ops;
729 	dev->ethtool_ops = &geneve_ethtool_ops;
730 	dev->destructor = free_netdev;
731 
732 	SET_NETDEV_DEVTYPE(dev, &geneve_type);
733 
734 	dev->features    |= NETIF_F_LLTX;
735 	dev->features    |= NETIF_F_SG | NETIF_F_HW_CSUM;
736 	dev->features    |= NETIF_F_RXCSUM;
737 	dev->features    |= NETIF_F_GSO_SOFTWARE;
738 
739 	dev->vlan_features = dev->features;
740 	dev->features    |= NETIF_F_HW_VLAN_CTAG_TX | NETIF_F_HW_VLAN_STAG_TX;
741 
742 	dev->hw_features |= NETIF_F_SG | NETIF_F_HW_CSUM | NETIF_F_RXCSUM;
743 	dev->hw_features |= NETIF_F_GSO_SOFTWARE;
744 	dev->hw_features |= NETIF_F_HW_VLAN_CTAG_TX | NETIF_F_HW_VLAN_STAG_TX;
745 
746 	netif_keep_dst(dev);
747 	dev->priv_flags |= IFF_LIVE_ADDR_CHANGE | IFF_NO_QUEUE;
748 	eth_hw_addr_random(dev);
749 }
750 
751 static const struct nla_policy geneve_policy[IFLA_GENEVE_MAX + 1] = {
752 	[IFLA_GENEVE_ID]		= { .type = NLA_U32 },
753 	[IFLA_GENEVE_REMOTE]		= { .len = FIELD_SIZEOF(struct iphdr, daddr) },
754 	[IFLA_GENEVE_TTL]		= { .type = NLA_U8 },
755 	[IFLA_GENEVE_TOS]		= { .type = NLA_U8 },
756 	[IFLA_GENEVE_PORT]		= { .type = NLA_U16 },
757 	[IFLA_GENEVE_COLLECT_METADATA]	= { .type = NLA_FLAG },
758 };
759 
760 static int geneve_validate(struct nlattr *tb[], struct nlattr *data[])
761 {
762 	if (tb[IFLA_ADDRESS]) {
763 		if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
764 			return -EINVAL;
765 
766 		if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
767 			return -EADDRNOTAVAIL;
768 	}
769 
770 	if (!data)
771 		return -EINVAL;
772 
773 	if (data[IFLA_GENEVE_ID]) {
774 		__u32 vni =  nla_get_u32(data[IFLA_GENEVE_ID]);
775 
776 		if (vni >= GENEVE_VID_MASK)
777 			return -ERANGE;
778 	}
779 
780 	return 0;
781 }
782 
783 static struct geneve_dev *geneve_find_dev(struct geneve_net *gn,
784 					  __be16 dst_port,
785 					  __be32 rem_addr,
786 					  u8 vni[],
787 					  bool *tun_on_same_port,
788 					  bool *tun_collect_md)
789 {
790 	struct geneve_dev *geneve, *t;
791 
792 	*tun_on_same_port = false;
793 	*tun_collect_md = false;
794 	t = NULL;
795 	list_for_each_entry(geneve, &gn->geneve_list, next) {
796 		if (geneve->dst_port == dst_port) {
797 			*tun_collect_md = geneve->collect_md;
798 			*tun_on_same_port = true;
799 		}
800 		if (!memcmp(vni, geneve->vni, sizeof(geneve->vni)) &&
801 		    rem_addr == geneve->remote.sin_addr.s_addr &&
802 		    dst_port == geneve->dst_port)
803 			t = geneve;
804 	}
805 	return t;
806 }
807 
808 static int geneve_configure(struct net *net, struct net_device *dev,
809 			    __be32 rem_addr, __u32 vni, __u8 ttl, __u8 tos,
810 			    __u16 dst_port, bool metadata)
811 {
812 	struct geneve_net *gn = net_generic(net, geneve_net_id);
813 	struct geneve_dev *t, *geneve = netdev_priv(dev);
814 	bool tun_collect_md, tun_on_same_port;
815 	int err;
816 
817 	if (metadata) {
818 		if (rem_addr || vni || tos || ttl)
819 			return -EINVAL;
820 	}
821 
822 	geneve->net = net;
823 	geneve->dev = dev;
824 
825 	geneve->vni[0] = (vni & 0x00ff0000) >> 16;
826 	geneve->vni[1] = (vni & 0x0000ff00) >> 8;
827 	geneve->vni[2] =  vni & 0x000000ff;
828 
829 	geneve->remote.sin_addr.s_addr = rem_addr;
830 	if (IN_MULTICAST(ntohl(geneve->remote.sin_addr.s_addr)))
831 		return -EINVAL;
832 
833 	geneve->ttl = ttl;
834 	geneve->tos = tos;
835 	geneve->dst_port = htons(dst_port);
836 	geneve->collect_md = metadata;
837 
838 	t = geneve_find_dev(gn, htons(dst_port), rem_addr, geneve->vni,
839 			    &tun_on_same_port, &tun_collect_md);
840 	if (t)
841 		return -EBUSY;
842 
843 	if (metadata) {
844 		if (tun_on_same_port)
845 			return -EPERM;
846 	} else {
847 		if (tun_collect_md)
848 			return -EPERM;
849 	}
850 
851 	err = register_netdevice(dev);
852 	if (err)
853 		return err;
854 
855 	list_add(&geneve->next, &gn->geneve_list);
856 	return 0;
857 }
858 
859 static int geneve_newlink(struct net *net, struct net_device *dev,
860 			  struct nlattr *tb[], struct nlattr *data[])
861 {
862 	__u16 dst_port = GENEVE_UDP_PORT;
863 	__u8 ttl = 0, tos = 0;
864 	bool metadata = false;
865 	__be32 rem_addr;
866 	__u32 vni;
867 
868 	if (!data[IFLA_GENEVE_ID] || !data[IFLA_GENEVE_REMOTE])
869 		return -EINVAL;
870 
871 	vni = nla_get_u32(data[IFLA_GENEVE_ID]);
872 	rem_addr = nla_get_in_addr(data[IFLA_GENEVE_REMOTE]);
873 
874 	if (data[IFLA_GENEVE_TTL])
875 		ttl = nla_get_u8(data[IFLA_GENEVE_TTL]);
876 
877 	if (data[IFLA_GENEVE_TOS])
878 		tos = nla_get_u8(data[IFLA_GENEVE_TOS]);
879 
880 	if (data[IFLA_GENEVE_PORT])
881 		dst_port = nla_get_u16(data[IFLA_GENEVE_PORT]);
882 
883 	if (data[IFLA_GENEVE_COLLECT_METADATA])
884 		metadata = true;
885 
886 	return geneve_configure(net, dev, rem_addr, vni,
887 				ttl, tos, dst_port, metadata);
888 }
889 
890 static void geneve_dellink(struct net_device *dev, struct list_head *head)
891 {
892 	struct geneve_dev *geneve = netdev_priv(dev);
893 
894 	list_del(&geneve->next);
895 	unregister_netdevice_queue(dev, head);
896 }
897 
898 static size_t geneve_get_size(const struct net_device *dev)
899 {
900 	return nla_total_size(sizeof(__u32)) +	/* IFLA_GENEVE_ID */
901 		nla_total_size(sizeof(struct in_addr)) + /* IFLA_GENEVE_REMOTE */
902 		nla_total_size(sizeof(__u8)) +  /* IFLA_GENEVE_TTL */
903 		nla_total_size(sizeof(__u8)) +  /* IFLA_GENEVE_TOS */
904 		nla_total_size(sizeof(__u16)) +  /* IFLA_GENEVE_PORT */
905 		nla_total_size(0) +	 /* IFLA_GENEVE_COLLECT_METADATA */
906 		0;
907 }
908 
909 static int geneve_fill_info(struct sk_buff *skb, const struct net_device *dev)
910 {
911 	struct geneve_dev *geneve = netdev_priv(dev);
912 	__u32 vni;
913 
914 	vni = (geneve->vni[0] << 16) | (geneve->vni[1] << 8) | geneve->vni[2];
915 	if (nla_put_u32(skb, IFLA_GENEVE_ID, vni))
916 		goto nla_put_failure;
917 
918 	if (nla_put_in_addr(skb, IFLA_GENEVE_REMOTE,
919 			    geneve->remote.sin_addr.s_addr))
920 		goto nla_put_failure;
921 
922 	if (nla_put_u8(skb, IFLA_GENEVE_TTL, geneve->ttl) ||
923 	    nla_put_u8(skb, IFLA_GENEVE_TOS, geneve->tos))
924 		goto nla_put_failure;
925 
926 	if (nla_put_u16(skb, IFLA_GENEVE_PORT, ntohs(geneve->dst_port)))
927 		goto nla_put_failure;
928 
929 	if (geneve->collect_md) {
930 		if (nla_put_flag(skb, IFLA_GENEVE_COLLECT_METADATA))
931 			goto nla_put_failure;
932 	}
933 
934 	return 0;
935 
936 nla_put_failure:
937 	return -EMSGSIZE;
938 }
939 
940 static struct rtnl_link_ops geneve_link_ops __read_mostly = {
941 	.kind		= "geneve",
942 	.maxtype	= IFLA_GENEVE_MAX,
943 	.policy		= geneve_policy,
944 	.priv_size	= sizeof(struct geneve_dev),
945 	.setup		= geneve_setup,
946 	.validate	= geneve_validate,
947 	.newlink	= geneve_newlink,
948 	.dellink	= geneve_dellink,
949 	.get_size	= geneve_get_size,
950 	.fill_info	= geneve_fill_info,
951 };
952 
953 struct net_device *geneve_dev_create_fb(struct net *net, const char *name,
954 					u8 name_assign_type, u16 dst_port)
955 {
956 	struct nlattr *tb[IFLA_MAX + 1];
957 	struct net_device *dev;
958 	int err;
959 
960 	memset(tb, 0, sizeof(tb));
961 	dev = rtnl_create_link(net, name, name_assign_type,
962 			       &geneve_link_ops, tb);
963 	if (IS_ERR(dev))
964 		return dev;
965 
966 	err = geneve_configure(net, dev, 0, 0, 0, 0, dst_port, true);
967 	if (err) {
968 		free_netdev(dev);
969 		return ERR_PTR(err);
970 	}
971 	return dev;
972 }
973 EXPORT_SYMBOL_GPL(geneve_dev_create_fb);
974 
975 static __net_init int geneve_init_net(struct net *net)
976 {
977 	struct geneve_net *gn = net_generic(net, geneve_net_id);
978 
979 	INIT_LIST_HEAD(&gn->geneve_list);
980 	INIT_LIST_HEAD(&gn->sock_list);
981 	return 0;
982 }
983 
984 static void __net_exit geneve_exit_net(struct net *net)
985 {
986 	struct geneve_net *gn = net_generic(net, geneve_net_id);
987 	struct geneve_dev *geneve, *next;
988 	struct net_device *dev, *aux;
989 	LIST_HEAD(list);
990 
991 	rtnl_lock();
992 
993 	/* gather any geneve devices that were moved into this ns */
994 	for_each_netdev_safe(net, dev, aux)
995 		if (dev->rtnl_link_ops == &geneve_link_ops)
996 			unregister_netdevice_queue(dev, &list);
997 
998 	/* now gather any other geneve devices that were created in this ns */
999 	list_for_each_entry_safe(geneve, next, &gn->geneve_list, next) {
1000 		/* If geneve->dev is in the same netns, it was already added
1001 		 * to the list by the previous loop.
1002 		 */
1003 		if (!net_eq(dev_net(geneve->dev), net))
1004 			unregister_netdevice_queue(geneve->dev, &list);
1005 	}
1006 
1007 	/* unregister the devices gathered above */
1008 	unregister_netdevice_many(&list);
1009 	rtnl_unlock();
1010 }
1011 
1012 static struct pernet_operations geneve_net_ops = {
1013 	.init = geneve_init_net,
1014 	.exit = geneve_exit_net,
1015 	.id   = &geneve_net_id,
1016 	.size = sizeof(struct geneve_net),
1017 };
1018 
1019 static int __init geneve_init_module(void)
1020 {
1021 	int rc;
1022 
1023 	rc = register_pernet_subsys(&geneve_net_ops);
1024 	if (rc)
1025 		goto out1;
1026 
1027 	rc = rtnl_link_register(&geneve_link_ops);
1028 	if (rc)
1029 		goto out2;
1030 
1031 	return 0;
1032 out2:
1033 	unregister_pernet_subsys(&geneve_net_ops);
1034 out1:
1035 	return rc;
1036 }
1037 late_initcall(geneve_init_module);
1038 
1039 static void __exit geneve_cleanup_module(void)
1040 {
1041 	rtnl_link_unregister(&geneve_link_ops);
1042 	unregister_pernet_subsys(&geneve_net_ops);
1043 }
1044 module_exit(geneve_cleanup_module);
1045 
1046 MODULE_LICENSE("GPL");
1047 MODULE_VERSION(GENEVE_NETDEV_VER);
1048 MODULE_AUTHOR("John W. Linville <linville@tuxdriver.com>");
1049 MODULE_DESCRIPTION("Interface driver for GENEVE encapsulated traffic");
1050 MODULE_ALIAS_RTNL_LINK("geneve");
1051