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1/*
2 * Linux NET3: GRE over IP protocol decoder.
3 *
4 * Authors: Alexey Kuznetsov (kuznet@ms2.inr.ac.ru)
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
10 *
11 */
12
13#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
14
15#include <linux/capability.h>
16#include <linux/module.h>
17#include <linux/types.h>
18#include <linux/kernel.h>
19#include <linux/slab.h>
20#include <asm/uaccess.h>
21#include <linux/skbuff.h>
22#include <linux/netdevice.h>
23#include <linux/in.h>
24#include <linux/tcp.h>
25#include <linux/udp.h>
26#include <linux/if_arp.h>
27#include <linux/mroute.h>
28#include <linux/init.h>
29#include <linux/in6.h>
30#include <linux/inetdevice.h>
31#include <linux/igmp.h>
32#include <linux/netfilter_ipv4.h>
33#include <linux/etherdevice.h>
34#include <linux/if_ether.h>
35
36#include <net/sock.h>
37#include <net/ip.h>
38#include <net/icmp.h>
39#include <net/protocol.h>
40#include <net/ip_tunnels.h>
41#include <net/arp.h>
42#include <net/checksum.h>
43#include <net/dsfield.h>
44#include <net/inet_ecn.h>
45#include <net/xfrm.h>
46#include <net/net_namespace.h>
47#include <net/netns/generic.h>
48#include <net/rtnetlink.h>
49#include <net/gre.h>
50
51#if IS_ENABLED(CONFIG_IPV6)
52#include <net/ipv6.h>
53#include <net/ip6_fib.h>
54#include <net/ip6_route.h>
55#endif
56
57/*
58 Problems & solutions
59 --------------------
60
61 1. The most important issue is detecting local dead loops.
62 They would cause complete host lockup in transmit, which
63 would be "resolved" by stack overflow or, if queueing is enabled,
64 with infinite looping in net_bh.
65
66 We cannot track such dead loops during route installation,
67 it is infeasible task. The most general solutions would be
68 to keep skb->encapsulation counter (sort of local ttl),
69 and silently drop packet when it expires. It is a good
70 solution, but it supposes maintaining new variable in ALL
71 skb, even if no tunneling is used.
72
73 Current solution: xmit_recursion breaks dead loops. This is a percpu
74 counter, since when we enter the first ndo_xmit(), cpu migration is
75 forbidden. We force an exit if this counter reaches RECURSION_LIMIT
76
77 2. Networking dead loops would not kill routers, but would really
78 kill network. IP hop limit plays role of "t->recursion" in this case,
79 if we copy it from packet being encapsulated to upper header.
80 It is very good solution, but it introduces two problems:
81
82 - Routing protocols, using packets with ttl=1 (OSPF, RIP2),
83 do not work over tunnels.
84 - traceroute does not work. I planned to relay ICMP from tunnel,
85 so that this problem would be solved and traceroute output
86 would even more informative. This idea appeared to be wrong:
87 only Linux complies to rfc1812 now (yes, guys, Linux is the only
88 true router now :-)), all routers (at least, in neighbourhood of mine)
89 return only 8 bytes of payload. It is the end.
90
91 Hence, if we want that OSPF worked or traceroute said something reasonable,
92 we should search for another solution.
93
94 One of them is to parse packet trying to detect inner encapsulation
95 made by our node. It is difficult or even impossible, especially,
96 taking into account fragmentation. TO be short, ttl is not solution at all.
97
98 Current solution: The solution was UNEXPECTEDLY SIMPLE.
99 We force DF flag on tunnels with preconfigured hop limit,
100 that is ALL. :-) Well, it does not remove the problem completely,
101 but exponential growth of network traffic is changed to linear
102 (branches, that exceed pmtu are pruned) and tunnel mtu
103 rapidly degrades to value <68, where looping stops.
104 Yes, it is not good if there exists a router in the loop,
105 which does not force DF, even when encapsulating packets have DF set.
106 But it is not our problem! Nobody could accuse us, we made
107 all that we could make. Even if it is your gated who injected
108 fatal route to network, even if it were you who configured
109 fatal static route: you are innocent. :-)
110
111 Alexey Kuznetsov.
112 */
113
114static bool log_ecn_error = true;
115module_param(log_ecn_error, bool, 0644);
116MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN");
117
118static struct rtnl_link_ops ipgre_link_ops __read_mostly;
119static int ipgre_tunnel_init(struct net_device *dev);
120
121static int ipgre_net_id __read_mostly;
122static int gre_tap_net_id __read_mostly;
123
124static int ipgre_err(struct sk_buff *skb, u32 info,
125 const struct tnl_ptk_info *tpi)
126{
127
128 /* All the routers (except for Linux) return only
129 8 bytes of packet payload. It means, that precise relaying of
130 ICMP in the real Internet is absolutely infeasible.
131
132 Moreover, Cisco "wise men" put GRE key to the third word
133 in GRE header. It makes impossible maintaining even soft
134 state for keyed GRE tunnels with enabled checksum. Tell
135 them "thank you".
136
137 Well, I wonder, rfc1812 was written by Cisco employee,
138 what the hell these idiots break standards established
139 by themselves???
140 */
141 struct net *net = dev_net(skb->dev);
142 struct ip_tunnel_net *itn;
143 const struct iphdr *iph;
144 const int type = icmp_hdr(skb)->type;
145 const int code = icmp_hdr(skb)->code;
146 struct ip_tunnel *t;
147
148 switch (type) {
149 default:
150 case ICMP_PARAMETERPROB:
151 return PACKET_RCVD;
152
153 case ICMP_DEST_UNREACH:
154 switch (code) {
155 case ICMP_SR_FAILED:
156 case ICMP_PORT_UNREACH:
157 /* Impossible event. */
158 return PACKET_RCVD;
159 default:
160 /* All others are translated to HOST_UNREACH.
161 rfc2003 contains "deep thoughts" about NET_UNREACH,
162 I believe they are just ether pollution. --ANK
163 */
164 break;
165 }
166 break;
167 case ICMP_TIME_EXCEEDED:
168 if (code != ICMP_EXC_TTL)
169 return PACKET_RCVD;
170 break;
171
172 case ICMP_REDIRECT:
173 break;
174 }
175
176 if (tpi->proto == htons(ETH_P_TEB))
177 itn = net_generic(net, gre_tap_net_id);
178 else
179 itn = net_generic(net, ipgre_net_id);
180
181 iph = (const struct iphdr *)(icmp_hdr(skb) + 1);
182 t = ip_tunnel_lookup(itn, skb->dev->ifindex, tpi->flags,
183 iph->daddr, iph->saddr, tpi->key);
184
185 if (t == NULL)
186 return PACKET_REJECT;
187
188 if (t->parms.iph.daddr == 0 ||
189 ipv4_is_multicast(t->parms.iph.daddr))
190 return PACKET_RCVD;
191
192 if (t->parms.iph.ttl == 0 && type == ICMP_TIME_EXCEEDED)
193 return PACKET_RCVD;
194
195 if (time_before(jiffies, t->err_time + IPTUNNEL_ERR_TIMEO))
196 t->err_count++;
197 else
198 t->err_count = 1;
199 t->err_time = jiffies;
200 return PACKET_RCVD;
201}
202
203static int ipgre_rcv(struct sk_buff *skb, const struct tnl_ptk_info *tpi)
204{
205 struct net *net = dev_net(skb->dev);
206 struct ip_tunnel_net *itn;
207 const struct iphdr *iph;
208 struct ip_tunnel *tunnel;
209
210 if (tpi->proto == htons(ETH_P_TEB))
211 itn = net_generic(net, gre_tap_net_id);
212 else
213 itn = net_generic(net, ipgre_net_id);
214
215 iph = ip_hdr(skb);
216 tunnel = ip_tunnel_lookup(itn, skb->dev->ifindex, tpi->flags,
217 iph->saddr, iph->daddr, tpi->key);
218
219 if (tunnel) {
220 skb_pop_mac_header(skb);
221 ip_tunnel_rcv(tunnel, skb, tpi, log_ecn_error);
222 return PACKET_RCVD;
223 }
224 return PACKET_REJECT;
225}
226
227static void __gre_xmit(struct sk_buff *skb, struct net_device *dev,
228 const struct iphdr *tnl_params,
229 __be16 proto)
230{
231 struct ip_tunnel *tunnel = netdev_priv(dev);
232 struct tnl_ptk_info tpi;
233
234 tpi.flags = tunnel->parms.o_flags;
235 tpi.proto = proto;
236 tpi.key = tunnel->parms.o_key;
237 if (tunnel->parms.o_flags & TUNNEL_SEQ)
238 tunnel->o_seqno++;
239 tpi.seq = htonl(tunnel->o_seqno);
240
241 /* Push GRE header. */
242 gre_build_header(skb, &tpi, tunnel->hlen);
243
244 ip_tunnel_xmit(skb, dev, tnl_params, tnl_params->protocol);
245}
246
247static netdev_tx_t ipgre_xmit(struct sk_buff *skb,
248 struct net_device *dev)
249{
250 struct ip_tunnel *tunnel = netdev_priv(dev);
251 const struct iphdr *tnl_params;
252
253 skb = gre_handle_offloads(skb, !!(tunnel->parms.o_flags&TUNNEL_CSUM));
254 if (IS_ERR(skb))
255 goto out;
256
257 if (dev->header_ops) {
258 /* Need space for new headers */
259 if (skb_cow_head(skb, dev->needed_headroom -
260 (tunnel->hlen + sizeof(struct iphdr))))
261 goto free_skb;
262
263 tnl_params = (const struct iphdr *)skb->data;
264
265 /* Pull skb since ip_tunnel_xmit() needs skb->data pointing
266 * to gre header.
267 */
268 skb_pull(skb, tunnel->hlen + sizeof(struct iphdr));
269 } else {
270 if (skb_cow_head(skb, dev->needed_headroom))
271 goto free_skb;
272
273 tnl_params = &tunnel->parms.iph;
274 }
275
276 __gre_xmit(skb, dev, tnl_params, skb->protocol);
277
278 return NETDEV_TX_OK;
279
280free_skb:
281 kfree_skb(skb);
282out:
283 dev->stats.tx_dropped++;
284 return NETDEV_TX_OK;
285}
286
287static netdev_tx_t gre_tap_xmit(struct sk_buff *skb,
288 struct net_device *dev)
289{
290 struct ip_tunnel *tunnel = netdev_priv(dev);
291
292 skb = gre_handle_offloads(skb, !!(tunnel->parms.o_flags&TUNNEL_CSUM));
293 if (IS_ERR(skb))
294 goto out;
295
296 if (skb_cow_head(skb, dev->needed_headroom))
297 goto free_skb;
298
299 __gre_xmit(skb, dev, &tunnel->parms.iph, htons(ETH_P_TEB));
300
301 return NETDEV_TX_OK;
302
303free_skb:
304 kfree_skb(skb);
305out:
306 dev->stats.tx_dropped++;
307 return NETDEV_TX_OK;
308}
309
310static int ipgre_tunnel_ioctl(struct net_device *dev,
311 struct ifreq *ifr, int cmd)
312{
313 int err = 0;
314 struct ip_tunnel_parm p;
315
316 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
317 return -EFAULT;
318 if (cmd == SIOCADDTUNNEL || cmd == SIOCCHGTUNNEL) {
319 if (p.iph.version != 4 || p.iph.protocol != IPPROTO_GRE ||
320 p.iph.ihl != 5 || (p.iph.frag_off&htons(~IP_DF)) ||
321 ((p.i_flags|p.o_flags)&(GRE_VERSION|GRE_ROUTING)))
322 return -EINVAL;
323 }
324 p.i_flags = gre_flags_to_tnl_flags(p.i_flags);
325 p.o_flags = gre_flags_to_tnl_flags(p.o_flags);
326
327 err = ip_tunnel_ioctl(dev, &p, cmd);
328 if (err)
329 return err;
330
331 p.i_flags = tnl_flags_to_gre_flags(p.i_flags);
332 p.o_flags = tnl_flags_to_gre_flags(p.o_flags);
333
334 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
335 return -EFAULT;
336 return 0;
337}
338
339/* Nice toy. Unfortunately, useless in real life :-)
340 It allows to construct virtual multiprotocol broadcast "LAN"
341 over the Internet, provided multicast routing is tuned.
342
343
344 I have no idea was this bicycle invented before me,
345 so that I had to set ARPHRD_IPGRE to a random value.
346 I have an impression, that Cisco could make something similar,
347 but this feature is apparently missing in IOS<=11.2(8).
348
349 I set up 10.66.66/24 and fec0:6666:6666::0/96 as virtual networks
350 with broadcast 224.66.66.66. If you have access to mbone, play with me :-)
351
352 ping -t 255 224.66.66.66
353
354 If nobody answers, mbone does not work.
355
356 ip tunnel add Universe mode gre remote 224.66.66.66 local <Your_real_addr> ttl 255
357 ip addr add 10.66.66.<somewhat>/24 dev Universe
358 ifconfig Universe up
359 ifconfig Universe add fe80::<Your_real_addr>/10
360 ifconfig Universe add fec0:6666:6666::<Your_real_addr>/96
361 ftp 10.66.66.66
362 ...
363 ftp fec0:6666:6666::193.233.7.65
364 ...
365 */
366static int ipgre_header(struct sk_buff *skb, struct net_device *dev,
367 unsigned short type,
368 const void *daddr, const void *saddr, unsigned int len)
369{
370 struct ip_tunnel *t = netdev_priv(dev);
371 struct iphdr *iph;
372 struct gre_base_hdr *greh;
373
374 iph = (struct iphdr *)skb_push(skb, t->hlen + sizeof(*iph));
375 greh = (struct gre_base_hdr *)(iph+1);
376 greh->flags = tnl_flags_to_gre_flags(t->parms.o_flags);
377 greh->protocol = htons(type);
378
379 memcpy(iph, &t->parms.iph, sizeof(struct iphdr));
380
381 /* Set the source hardware address. */
382 if (saddr)
383 memcpy(&iph->saddr, saddr, 4);
384 if (daddr)
385 memcpy(&iph->daddr, daddr, 4);
386 if (iph->daddr)
387 return t->hlen + sizeof(*iph);
388
389 return -(t->hlen + sizeof(*iph));
390}
391
392static int ipgre_header_parse(const struct sk_buff *skb, unsigned char *haddr)
393{
394 const struct iphdr *iph = (const struct iphdr *) skb_mac_header(skb);
395 memcpy(haddr, &iph->saddr, 4);
396 return 4;
397}
398
399static const struct header_ops ipgre_header_ops = {
400 .create = ipgre_header,
401 .parse = ipgre_header_parse,
402};
403
404#ifdef CONFIG_NET_IPGRE_BROADCAST
405static int ipgre_open(struct net_device *dev)
406{
407 struct ip_tunnel *t = netdev_priv(dev);
408
409 if (ipv4_is_multicast(t->parms.iph.daddr)) {
410 struct flowi4 fl4;
411 struct rtable *rt;
412
413 rt = ip_route_output_gre(dev_net(dev), &fl4,
414 t->parms.iph.daddr,
415 t->parms.iph.saddr,
416 t->parms.o_key,
417 RT_TOS(t->parms.iph.tos),
418 t->parms.link);
419 if (IS_ERR(rt))
420 return -EADDRNOTAVAIL;
421 dev = rt->dst.dev;
422 ip_rt_put(rt);
423 if (__in_dev_get_rtnl(dev) == NULL)
424 return -EADDRNOTAVAIL;
425 t->mlink = dev->ifindex;
426 ip_mc_inc_group(__in_dev_get_rtnl(dev), t->parms.iph.daddr);
427 }
428 return 0;
429}
430
431static int ipgre_close(struct net_device *dev)
432{
433 struct ip_tunnel *t = netdev_priv(dev);
434
435 if (ipv4_is_multicast(t->parms.iph.daddr) && t->mlink) {
436 struct in_device *in_dev;
437 in_dev = inetdev_by_index(dev_net(dev), t->mlink);
438 if (in_dev)
439 ip_mc_dec_group(in_dev, t->parms.iph.daddr);
440 }
441 return 0;
442}
443#endif
444
445static const struct net_device_ops ipgre_netdev_ops = {
446 .ndo_init = ipgre_tunnel_init,
447 .ndo_uninit = ip_tunnel_uninit,
448#ifdef CONFIG_NET_IPGRE_BROADCAST
449 .ndo_open = ipgre_open,
450 .ndo_stop = ipgre_close,
451#endif
452 .ndo_start_xmit = ipgre_xmit,
453 .ndo_do_ioctl = ipgre_tunnel_ioctl,
454 .ndo_change_mtu = ip_tunnel_change_mtu,
455 .ndo_get_stats64 = ip_tunnel_get_stats64,
456};
457
458#define GRE_FEATURES (NETIF_F_SG | \
459 NETIF_F_FRAGLIST | \
460 NETIF_F_HIGHDMA | \
461 NETIF_F_HW_CSUM)
462
463static void ipgre_tunnel_setup(struct net_device *dev)
464{
465 dev->netdev_ops = &ipgre_netdev_ops;
466 dev->type = ARPHRD_IPGRE;
467 ip_tunnel_setup(dev, ipgre_net_id);
468}
469
470static void __gre_tunnel_init(struct net_device *dev)
471{
472 struct ip_tunnel *tunnel;
473
474 tunnel = netdev_priv(dev);
475 tunnel->hlen = ip_gre_calc_hlen(tunnel->parms.o_flags);
476 tunnel->parms.iph.protocol = IPPROTO_GRE;
477
478 dev->needed_headroom = LL_MAX_HEADER + sizeof(struct iphdr) + 4;
479 dev->mtu = ETH_DATA_LEN - sizeof(struct iphdr) - 4;
480
481 dev->features |= NETIF_F_NETNS_LOCAL | GRE_FEATURES;
482 dev->hw_features |= GRE_FEATURES;
483
484 if (!(tunnel->parms.o_flags & TUNNEL_SEQ)) {
485 /* TCP offload with GRE SEQ is not supported. */
486 dev->features |= NETIF_F_GSO_SOFTWARE;
487 dev->hw_features |= NETIF_F_GSO_SOFTWARE;
488 /* Can use a lockless transmit, unless we generate
489 * output sequences
490 */
491 dev->features |= NETIF_F_LLTX;
492 }
493}
494
495static int ipgre_tunnel_init(struct net_device *dev)
496{
497 struct ip_tunnel *tunnel = netdev_priv(dev);
498 struct iphdr *iph = &tunnel->parms.iph;
499
500 __gre_tunnel_init(dev);
501
502 memcpy(dev->dev_addr, &iph->saddr, 4);
503 memcpy(dev->broadcast, &iph->daddr, 4);
504
505 dev->flags = IFF_NOARP;
506 dev->priv_flags &= ~IFF_XMIT_DST_RELEASE;
507 dev->addr_len = 4;
508
509 if (iph->daddr) {
510#ifdef CONFIG_NET_IPGRE_BROADCAST
511 if (ipv4_is_multicast(iph->daddr)) {
512 if (!iph->saddr)
513 return -EINVAL;
514 dev->flags = IFF_BROADCAST;
515 dev->header_ops = &ipgre_header_ops;
516 }
517#endif
518 } else
519 dev->header_ops = &ipgre_header_ops;
520
521 return ip_tunnel_init(dev);
522}
523
524static struct gre_cisco_protocol ipgre_protocol = {
525 .handler = ipgre_rcv,
526 .err_handler = ipgre_err,
527 .priority = 0,
528};
529
530static int __net_init ipgre_init_net(struct net *net)
531{
532 return ip_tunnel_init_net(net, ipgre_net_id, &ipgre_link_ops, NULL);
533}
534
535static void __net_exit ipgre_exit_net(struct net *net)
536{
537 struct ip_tunnel_net *itn = net_generic(net, ipgre_net_id);
538 ip_tunnel_delete_net(itn, &ipgre_link_ops);
539}
540
541static struct pernet_operations ipgre_net_ops = {
542 .init = ipgre_init_net,
543 .exit = ipgre_exit_net,
544 .id = &ipgre_net_id,
545 .size = sizeof(struct ip_tunnel_net),
546};
547
548static int ipgre_tunnel_validate(struct nlattr *tb[], struct nlattr *data[])
549{
550 __be16 flags;
551
552 if (!data)
553 return 0;
554
555 flags = 0;
556 if (data[IFLA_GRE_IFLAGS])
557 flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]);
558 if (data[IFLA_GRE_OFLAGS])
559 flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]);
560 if (flags & (GRE_VERSION|GRE_ROUTING))
561 return -EINVAL;
562
563 return 0;
564}
565
566static int ipgre_tap_validate(struct nlattr *tb[], struct nlattr *data[])
567{
568 __be32 daddr;
569
570 if (tb[IFLA_ADDRESS]) {
571 if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
572 return -EINVAL;
573 if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
574 return -EADDRNOTAVAIL;
575 }
576
577 if (!data)
578 goto out;
579
580 if (data[IFLA_GRE_REMOTE]) {
581 memcpy(&daddr, nla_data(data[IFLA_GRE_REMOTE]), 4);
582 if (!daddr)
583 return -EINVAL;
584 }
585
586out:
587 return ipgre_tunnel_validate(tb, data);
588}
589
590static void ipgre_netlink_parms(struct nlattr *data[], struct nlattr *tb[],
591 struct ip_tunnel_parm *parms)
592{
593 memset(parms, 0, sizeof(*parms));
594
595 parms->iph.protocol = IPPROTO_GRE;
596
597 if (!data)
598 return;
599
600 if (data[IFLA_GRE_LINK])
601 parms->link = nla_get_u32(data[IFLA_GRE_LINK]);
602
603 if (data[IFLA_GRE_IFLAGS])
604 parms->i_flags = gre_flags_to_tnl_flags(nla_get_be16(data[IFLA_GRE_IFLAGS]));
605
606 if (data[IFLA_GRE_OFLAGS])
607 parms->o_flags = gre_flags_to_tnl_flags(nla_get_be16(data[IFLA_GRE_OFLAGS]));
608
609 if (data[IFLA_GRE_IKEY])
610 parms->i_key = nla_get_be32(data[IFLA_GRE_IKEY]);
611
612 if (data[IFLA_GRE_OKEY])
613 parms->o_key = nla_get_be32(data[IFLA_GRE_OKEY]);
614
615 if (data[IFLA_GRE_LOCAL])
616 parms->iph.saddr = nla_get_be32(data[IFLA_GRE_LOCAL]);
617
618 if (data[IFLA_GRE_REMOTE])
619 parms->iph.daddr = nla_get_be32(data[IFLA_GRE_REMOTE]);
620
621 if (data[IFLA_GRE_TTL])
622 parms->iph.ttl = nla_get_u8(data[IFLA_GRE_TTL]);
623
624 if (data[IFLA_GRE_TOS])
625 parms->iph.tos = nla_get_u8(data[IFLA_GRE_TOS]);
626
627 if (!data[IFLA_GRE_PMTUDISC] || nla_get_u8(data[IFLA_GRE_PMTUDISC]))
628 parms->iph.frag_off = htons(IP_DF);
629}
630
631static int gre_tap_init(struct net_device *dev)
632{
633 __gre_tunnel_init(dev);
634
635 return ip_tunnel_init(dev);
636}
637
638static const struct net_device_ops gre_tap_netdev_ops = {
639 .ndo_init = gre_tap_init,
640 .ndo_uninit = ip_tunnel_uninit,
641 .ndo_start_xmit = gre_tap_xmit,
642 .ndo_set_mac_address = eth_mac_addr,
643 .ndo_validate_addr = eth_validate_addr,
644 .ndo_change_mtu = ip_tunnel_change_mtu,
645 .ndo_get_stats64 = ip_tunnel_get_stats64,
646};
647
648static void ipgre_tap_setup(struct net_device *dev)
649{
650 ether_setup(dev);
651 dev->netdev_ops = &gre_tap_netdev_ops;
652 ip_tunnel_setup(dev, gre_tap_net_id);
653}
654
655static int ipgre_newlink(struct net *src_net, struct net_device *dev,
656 struct nlattr *tb[], struct nlattr *data[])
657{
658 struct ip_tunnel_parm p;
659
660 ipgre_netlink_parms(data, tb, &p);
661 return ip_tunnel_newlink(dev, tb, &p);
662}
663
664static int ipgre_changelink(struct net_device *dev, struct nlattr *tb[],
665 struct nlattr *data[])
666{
667 struct ip_tunnel_parm p;
668
669 ipgre_netlink_parms(data, tb, &p);
670 return ip_tunnel_changelink(dev, tb, &p);
671}
672
673static size_t ipgre_get_size(const struct net_device *dev)
674{
675 return
676 /* IFLA_GRE_LINK */
677 nla_total_size(4) +
678 /* IFLA_GRE_IFLAGS */
679 nla_total_size(2) +
680 /* IFLA_GRE_OFLAGS */
681 nla_total_size(2) +
682 /* IFLA_GRE_IKEY */
683 nla_total_size(4) +
684 /* IFLA_GRE_OKEY */
685 nla_total_size(4) +
686 /* IFLA_GRE_LOCAL */
687 nla_total_size(4) +
688 /* IFLA_GRE_REMOTE */
689 nla_total_size(4) +
690 /* IFLA_GRE_TTL */
691 nla_total_size(1) +
692 /* IFLA_GRE_TOS */
693 nla_total_size(1) +
694 /* IFLA_GRE_PMTUDISC */
695 nla_total_size(1) +
696 0;
697}
698
699static int ipgre_fill_info(struct sk_buff *skb, const struct net_device *dev)
700{
701 struct ip_tunnel *t = netdev_priv(dev);
702 struct ip_tunnel_parm *p = &t->parms;
703
704 if (nla_put_u32(skb, IFLA_GRE_LINK, p->link) ||
705 nla_put_be16(skb, IFLA_GRE_IFLAGS, tnl_flags_to_gre_flags(p->i_flags)) ||
706 nla_put_be16(skb, IFLA_GRE_OFLAGS, tnl_flags_to_gre_flags(p->o_flags)) ||
707 nla_put_be32(skb, IFLA_GRE_IKEY, p->i_key) ||
708 nla_put_be32(skb, IFLA_GRE_OKEY, p->o_key) ||
709 nla_put_be32(skb, IFLA_GRE_LOCAL, p->iph.saddr) ||
710 nla_put_be32(skb, IFLA_GRE_REMOTE, p->iph.daddr) ||
711 nla_put_u8(skb, IFLA_GRE_TTL, p->iph.ttl) ||
712 nla_put_u8(skb, IFLA_GRE_TOS, p->iph.tos) ||
713 nla_put_u8(skb, IFLA_GRE_PMTUDISC,
714 !!(p->iph.frag_off & htons(IP_DF))))
715 goto nla_put_failure;
716 return 0;
717
718nla_put_failure:
719 return -EMSGSIZE;
720}
721
722static const struct nla_policy ipgre_policy[IFLA_GRE_MAX + 1] = {
723 [IFLA_GRE_LINK] = { .type = NLA_U32 },
724 [IFLA_GRE_IFLAGS] = { .type = NLA_U16 },
725 [IFLA_GRE_OFLAGS] = { .type = NLA_U16 },
726 [IFLA_GRE_IKEY] = { .type = NLA_U32 },
727 [IFLA_GRE_OKEY] = { .type = NLA_U32 },
728 [IFLA_GRE_LOCAL] = { .len = FIELD_SIZEOF(struct iphdr, saddr) },
729 [IFLA_GRE_REMOTE] = { .len = FIELD_SIZEOF(struct iphdr, daddr) },
730 [IFLA_GRE_TTL] = { .type = NLA_U8 },
731 [IFLA_GRE_TOS] = { .type = NLA_U8 },
732 [IFLA_GRE_PMTUDISC] = { .type = NLA_U8 },
733};
734
735static struct rtnl_link_ops ipgre_link_ops __read_mostly = {
736 .kind = "gre",
737 .maxtype = IFLA_GRE_MAX,
738 .policy = ipgre_policy,
739 .priv_size = sizeof(struct ip_tunnel),
740 .setup = ipgre_tunnel_setup,
741 .validate = ipgre_tunnel_validate,
742 .newlink = ipgre_newlink,
743 .changelink = ipgre_changelink,
744 .dellink = ip_tunnel_dellink,
745 .get_size = ipgre_get_size,
746 .fill_info = ipgre_fill_info,
747};
748
749static struct rtnl_link_ops ipgre_tap_ops __read_mostly = {
750 .kind = "gretap",
751 .maxtype = IFLA_GRE_MAX,
752 .policy = ipgre_policy,
753 .priv_size = sizeof(struct ip_tunnel),
754 .setup = ipgre_tap_setup,
755 .validate = ipgre_tap_validate,
756 .newlink = ipgre_newlink,
757 .changelink = ipgre_changelink,
758 .dellink = ip_tunnel_dellink,
759 .get_size = ipgre_get_size,
760 .fill_info = ipgre_fill_info,
761};
762
763static int __net_init ipgre_tap_init_net(struct net *net)
764{
765 return ip_tunnel_init_net(net, gre_tap_net_id, &ipgre_tap_ops, NULL);
766}
767
768static void __net_exit ipgre_tap_exit_net(struct net *net)
769{
770 struct ip_tunnel_net *itn = net_generic(net, gre_tap_net_id);
771 ip_tunnel_delete_net(itn, &ipgre_tap_ops);
772}
773
774static struct pernet_operations ipgre_tap_net_ops = {
775 .init = ipgre_tap_init_net,
776 .exit = ipgre_tap_exit_net,
777 .id = &gre_tap_net_id,
778 .size = sizeof(struct ip_tunnel_net),
779};
780
781static int __init ipgre_init(void)
782{
783 int err;
784
785 pr_info("GRE over IPv4 tunneling driver\n");
786
787 err = register_pernet_device(&ipgre_net_ops);
788 if (err < 0)
789 return err;
790
791 err = register_pernet_device(&ipgre_tap_net_ops);
792 if (err < 0)
793 goto pnet_tap_faied;
794
795 err = gre_cisco_register(&ipgre_protocol);
796 if (err < 0) {
797 pr_info("%s: can't add protocol\n", __func__);
798 goto add_proto_failed;
799 }
800
801 err = rtnl_link_register(&ipgre_link_ops);
802 if (err < 0)
803 goto rtnl_link_failed;
804
805 err = rtnl_link_register(&ipgre_tap_ops);
806 if (err < 0)
807 goto tap_ops_failed;
808
809 return 0;
810
811tap_ops_failed:
812 rtnl_link_unregister(&ipgre_link_ops);
813rtnl_link_failed:
814 gre_cisco_unregister(&ipgre_protocol);
815add_proto_failed:
816 unregister_pernet_device(&ipgre_tap_net_ops);
817pnet_tap_faied:
818 unregister_pernet_device(&ipgre_net_ops);
819 return err;
820}
821
822static void __exit ipgre_fini(void)
823{
824 rtnl_link_unregister(&ipgre_tap_ops);
825 rtnl_link_unregister(&ipgre_link_ops);
826 gre_cisco_unregister(&ipgre_protocol);
827 unregister_pernet_device(&ipgre_tap_net_ops);
828 unregister_pernet_device(&ipgre_net_ops);
829}
830
831module_init(ipgre_init);
832module_exit(ipgre_fini);
833MODULE_LICENSE("GPL");
834MODULE_ALIAS_RTNL_LINK("gre");
835MODULE_ALIAS_RTNL_LINK("gretap");
836MODULE_ALIAS_NETDEV("gre0");
837MODULE_ALIAS_NETDEV("gretap0");
1/*
2 * Linux NET3: GRE over IP protocol decoder.
3 *
4 * Authors: Alexey Kuznetsov (kuznet@ms2.inr.ac.ru)
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
10 *
11 */
12
13#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
14
15#include <linux/capability.h>
16#include <linux/module.h>
17#include <linux/types.h>
18#include <linux/kernel.h>
19#include <linux/slab.h>
20#include <linux/uaccess.h>
21#include <linux/skbuff.h>
22#include <linux/netdevice.h>
23#include <linux/in.h>
24#include <linux/tcp.h>
25#include <linux/udp.h>
26#include <linux/if_arp.h>
27#include <linux/if_vlan.h>
28#include <linux/init.h>
29#include <linux/in6.h>
30#include <linux/inetdevice.h>
31#include <linux/igmp.h>
32#include <linux/netfilter_ipv4.h>
33#include <linux/etherdevice.h>
34#include <linux/if_ether.h>
35
36#include <net/sock.h>
37#include <net/ip.h>
38#include <net/icmp.h>
39#include <net/protocol.h>
40#include <net/ip_tunnels.h>
41#include <net/arp.h>
42#include <net/checksum.h>
43#include <net/dsfield.h>
44#include <net/inet_ecn.h>
45#include <net/xfrm.h>
46#include <net/net_namespace.h>
47#include <net/netns/generic.h>
48#include <net/rtnetlink.h>
49#include <net/gre.h>
50#include <net/dst_metadata.h>
51#include <net/erspan.h>
52
53/*
54 Problems & solutions
55 --------------------
56
57 1. The most important issue is detecting local dead loops.
58 They would cause complete host lockup in transmit, which
59 would be "resolved" by stack overflow or, if queueing is enabled,
60 with infinite looping in net_bh.
61
62 We cannot track such dead loops during route installation,
63 it is infeasible task. The most general solutions would be
64 to keep skb->encapsulation counter (sort of local ttl),
65 and silently drop packet when it expires. It is a good
66 solution, but it supposes maintaining new variable in ALL
67 skb, even if no tunneling is used.
68
69 Current solution: xmit_recursion breaks dead loops. This is a percpu
70 counter, since when we enter the first ndo_xmit(), cpu migration is
71 forbidden. We force an exit if this counter reaches RECURSION_LIMIT
72
73 2. Networking dead loops would not kill routers, but would really
74 kill network. IP hop limit plays role of "t->recursion" in this case,
75 if we copy it from packet being encapsulated to upper header.
76 It is very good solution, but it introduces two problems:
77
78 - Routing protocols, using packets with ttl=1 (OSPF, RIP2),
79 do not work over tunnels.
80 - traceroute does not work. I planned to relay ICMP from tunnel,
81 so that this problem would be solved and traceroute output
82 would even more informative. This idea appeared to be wrong:
83 only Linux complies to rfc1812 now (yes, guys, Linux is the only
84 true router now :-)), all routers (at least, in neighbourhood of mine)
85 return only 8 bytes of payload. It is the end.
86
87 Hence, if we want that OSPF worked or traceroute said something reasonable,
88 we should search for another solution.
89
90 One of them is to parse packet trying to detect inner encapsulation
91 made by our node. It is difficult or even impossible, especially,
92 taking into account fragmentation. TO be short, ttl is not solution at all.
93
94 Current solution: The solution was UNEXPECTEDLY SIMPLE.
95 We force DF flag on tunnels with preconfigured hop limit,
96 that is ALL. :-) Well, it does not remove the problem completely,
97 but exponential growth of network traffic is changed to linear
98 (branches, that exceed pmtu are pruned) and tunnel mtu
99 rapidly degrades to value <68, where looping stops.
100 Yes, it is not good if there exists a router in the loop,
101 which does not force DF, even when encapsulating packets have DF set.
102 But it is not our problem! Nobody could accuse us, we made
103 all that we could make. Even if it is your gated who injected
104 fatal route to network, even if it were you who configured
105 fatal static route: you are innocent. :-)
106
107 Alexey Kuznetsov.
108 */
109
110static bool log_ecn_error = true;
111module_param(log_ecn_error, bool, 0644);
112MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN");
113
114static struct rtnl_link_ops ipgre_link_ops __read_mostly;
115static int ipgre_tunnel_init(struct net_device *dev);
116static void erspan_build_header(struct sk_buff *skb,
117 u32 id, u32 index,
118 bool truncate, bool is_ipv4);
119
120static unsigned int ipgre_net_id __read_mostly;
121static unsigned int gre_tap_net_id __read_mostly;
122static unsigned int erspan_net_id __read_mostly;
123
124static void ipgre_err(struct sk_buff *skb, u32 info,
125 const struct tnl_ptk_info *tpi)
126{
127
128 /* All the routers (except for Linux) return only
129 8 bytes of packet payload. It means, that precise relaying of
130 ICMP in the real Internet is absolutely infeasible.
131
132 Moreover, Cisco "wise men" put GRE key to the third word
133 in GRE header. It makes impossible maintaining even soft
134 state for keyed GRE tunnels with enabled checksum. Tell
135 them "thank you".
136
137 Well, I wonder, rfc1812 was written by Cisco employee,
138 what the hell these idiots break standards established
139 by themselves???
140 */
141 struct net *net = dev_net(skb->dev);
142 struct ip_tunnel_net *itn;
143 const struct iphdr *iph;
144 const int type = icmp_hdr(skb)->type;
145 const int code = icmp_hdr(skb)->code;
146 unsigned int data_len = 0;
147 struct ip_tunnel *t;
148
149 switch (type) {
150 default:
151 case ICMP_PARAMETERPROB:
152 return;
153
154 case ICMP_DEST_UNREACH:
155 switch (code) {
156 case ICMP_SR_FAILED:
157 case ICMP_PORT_UNREACH:
158 /* Impossible event. */
159 return;
160 default:
161 /* All others are translated to HOST_UNREACH.
162 rfc2003 contains "deep thoughts" about NET_UNREACH,
163 I believe they are just ether pollution. --ANK
164 */
165 break;
166 }
167 break;
168
169 case ICMP_TIME_EXCEEDED:
170 if (code != ICMP_EXC_TTL)
171 return;
172 data_len = icmp_hdr(skb)->un.reserved[1] * 4; /* RFC 4884 4.1 */
173 break;
174
175 case ICMP_REDIRECT:
176 break;
177 }
178
179 if (tpi->proto == htons(ETH_P_TEB))
180 itn = net_generic(net, gre_tap_net_id);
181 else
182 itn = net_generic(net, ipgre_net_id);
183
184 iph = (const struct iphdr *)(icmp_hdr(skb) + 1);
185 t = ip_tunnel_lookup(itn, skb->dev->ifindex, tpi->flags,
186 iph->daddr, iph->saddr, tpi->key);
187
188 if (!t)
189 return;
190
191#if IS_ENABLED(CONFIG_IPV6)
192 if (tpi->proto == htons(ETH_P_IPV6) &&
193 !ip6_err_gen_icmpv6_unreach(skb, iph->ihl * 4 + tpi->hdr_len,
194 type, data_len))
195 return;
196#endif
197
198 if (t->parms.iph.daddr == 0 ||
199 ipv4_is_multicast(t->parms.iph.daddr))
200 return;
201
202 if (t->parms.iph.ttl == 0 && type == ICMP_TIME_EXCEEDED)
203 return;
204
205 if (time_before(jiffies, t->err_time + IPTUNNEL_ERR_TIMEO))
206 t->err_count++;
207 else
208 t->err_count = 1;
209 t->err_time = jiffies;
210}
211
212static void gre_err(struct sk_buff *skb, u32 info)
213{
214 /* All the routers (except for Linux) return only
215 * 8 bytes of packet payload. It means, that precise relaying of
216 * ICMP in the real Internet is absolutely infeasible.
217 *
218 * Moreover, Cisco "wise men" put GRE key to the third word
219 * in GRE header. It makes impossible maintaining even soft
220 * state for keyed
221 * GRE tunnels with enabled checksum. Tell them "thank you".
222 *
223 * Well, I wonder, rfc1812 was written by Cisco employee,
224 * what the hell these idiots break standards established
225 * by themselves???
226 */
227
228 const struct iphdr *iph = (struct iphdr *)skb->data;
229 const int type = icmp_hdr(skb)->type;
230 const int code = icmp_hdr(skb)->code;
231 struct tnl_ptk_info tpi;
232 bool csum_err = false;
233
234 if (gre_parse_header(skb, &tpi, &csum_err, htons(ETH_P_IP),
235 iph->ihl * 4) < 0) {
236 if (!csum_err) /* ignore csum errors. */
237 return;
238 }
239
240 if (type == ICMP_DEST_UNREACH && code == ICMP_FRAG_NEEDED) {
241 ipv4_update_pmtu(skb, dev_net(skb->dev), info,
242 skb->dev->ifindex, 0, IPPROTO_GRE, 0);
243 return;
244 }
245 if (type == ICMP_REDIRECT) {
246 ipv4_redirect(skb, dev_net(skb->dev), skb->dev->ifindex, 0,
247 IPPROTO_GRE, 0);
248 return;
249 }
250
251 ipgre_err(skb, info, &tpi);
252}
253
254static int erspan_rcv(struct sk_buff *skb, struct tnl_ptk_info *tpi,
255 int gre_hdr_len)
256{
257 struct net *net = dev_net(skb->dev);
258 struct metadata_dst *tun_dst = NULL;
259 struct erspan_base_hdr *ershdr;
260 struct erspan_metadata *pkt_md;
261 struct ip_tunnel_net *itn;
262 struct ip_tunnel *tunnel;
263 const struct iphdr *iph;
264 struct erspan_md2 *md2;
265 int ver;
266 int len;
267
268 itn = net_generic(net, erspan_net_id);
269 len = gre_hdr_len + sizeof(*ershdr);
270
271 /* Check based hdr len */
272 if (unlikely(!pskb_may_pull(skb, len)))
273 return PACKET_REJECT;
274
275 iph = ip_hdr(skb);
276 ershdr = (struct erspan_base_hdr *)(skb->data + gre_hdr_len);
277 ver = ershdr->ver;
278
279 /* The original GRE header does not have key field,
280 * Use ERSPAN 10-bit session ID as key.
281 */
282 tpi->key = cpu_to_be32(get_session_id(ershdr));
283 tunnel = ip_tunnel_lookup(itn, skb->dev->ifindex,
284 tpi->flags | TUNNEL_KEY,
285 iph->saddr, iph->daddr, tpi->key);
286
287 if (tunnel) {
288 len = gre_hdr_len + erspan_hdr_len(ver);
289 if (unlikely(!pskb_may_pull(skb, len)))
290 return PACKET_REJECT;
291
292 ershdr = (struct erspan_base_hdr *)(skb->data + gre_hdr_len);
293 pkt_md = (struct erspan_metadata *)(ershdr + 1);
294
295 if (__iptunnel_pull_header(skb,
296 len,
297 htons(ETH_P_TEB),
298 false, false) < 0)
299 goto drop;
300
301 if (tunnel->collect_md) {
302 struct ip_tunnel_info *info;
303 struct erspan_metadata *md;
304 __be64 tun_id;
305 __be16 flags;
306
307 tpi->flags |= TUNNEL_KEY;
308 flags = tpi->flags;
309 tun_id = key32_to_tunnel_id(tpi->key);
310
311 tun_dst = ip_tun_rx_dst(skb, flags,
312 tun_id, sizeof(*md));
313 if (!tun_dst)
314 return PACKET_REJECT;
315
316 md = ip_tunnel_info_opts(&tun_dst->u.tun_info);
317 md->version = ver;
318 md2 = &md->u.md2;
319 memcpy(md2, pkt_md, ver == 1 ? ERSPAN_V1_MDSIZE :
320 ERSPAN_V2_MDSIZE);
321
322 info = &tun_dst->u.tun_info;
323 info->key.tun_flags |= TUNNEL_ERSPAN_OPT;
324 info->options_len = sizeof(*md);
325 }
326
327 skb_reset_mac_header(skb);
328 ip_tunnel_rcv(tunnel, skb, tpi, tun_dst, log_ecn_error);
329 return PACKET_RCVD;
330 }
331drop:
332 kfree_skb(skb);
333 return PACKET_RCVD;
334}
335
336static int __ipgre_rcv(struct sk_buff *skb, const struct tnl_ptk_info *tpi,
337 struct ip_tunnel_net *itn, int hdr_len, bool raw_proto)
338{
339 struct metadata_dst *tun_dst = NULL;
340 const struct iphdr *iph;
341 struct ip_tunnel *tunnel;
342
343 iph = ip_hdr(skb);
344 tunnel = ip_tunnel_lookup(itn, skb->dev->ifindex, tpi->flags,
345 iph->saddr, iph->daddr, tpi->key);
346
347 if (tunnel) {
348 if (__iptunnel_pull_header(skb, hdr_len, tpi->proto,
349 raw_proto, false) < 0)
350 goto drop;
351
352 if (tunnel->dev->type != ARPHRD_NONE)
353 skb_pop_mac_header(skb);
354 else
355 skb_reset_mac_header(skb);
356 if (tunnel->collect_md) {
357 __be16 flags;
358 __be64 tun_id;
359
360 flags = tpi->flags & (TUNNEL_CSUM | TUNNEL_KEY);
361 tun_id = key32_to_tunnel_id(tpi->key);
362 tun_dst = ip_tun_rx_dst(skb, flags, tun_id, 0);
363 if (!tun_dst)
364 return PACKET_REJECT;
365 }
366
367 ip_tunnel_rcv(tunnel, skb, tpi, tun_dst, log_ecn_error);
368 return PACKET_RCVD;
369 }
370 return PACKET_NEXT;
371
372drop:
373 kfree_skb(skb);
374 return PACKET_RCVD;
375}
376
377static int ipgre_rcv(struct sk_buff *skb, const struct tnl_ptk_info *tpi,
378 int hdr_len)
379{
380 struct net *net = dev_net(skb->dev);
381 struct ip_tunnel_net *itn;
382 int res;
383
384 if (tpi->proto == htons(ETH_P_TEB))
385 itn = net_generic(net, gre_tap_net_id);
386 else
387 itn = net_generic(net, ipgre_net_id);
388
389 res = __ipgre_rcv(skb, tpi, itn, hdr_len, false);
390 if (res == PACKET_NEXT && tpi->proto == htons(ETH_P_TEB)) {
391 /* ipgre tunnels in collect metadata mode should receive
392 * also ETH_P_TEB traffic.
393 */
394 itn = net_generic(net, ipgre_net_id);
395 res = __ipgre_rcv(skb, tpi, itn, hdr_len, true);
396 }
397 return res;
398}
399
400static int gre_rcv(struct sk_buff *skb)
401{
402 struct tnl_ptk_info tpi;
403 bool csum_err = false;
404 int hdr_len;
405
406#ifdef CONFIG_NET_IPGRE_BROADCAST
407 if (ipv4_is_multicast(ip_hdr(skb)->daddr)) {
408 /* Looped back packet, drop it! */
409 if (rt_is_output_route(skb_rtable(skb)))
410 goto drop;
411 }
412#endif
413
414 hdr_len = gre_parse_header(skb, &tpi, &csum_err, htons(ETH_P_IP), 0);
415 if (hdr_len < 0)
416 goto drop;
417
418 if (unlikely(tpi.proto == htons(ETH_P_ERSPAN) ||
419 tpi.proto == htons(ETH_P_ERSPAN2))) {
420 if (erspan_rcv(skb, &tpi, hdr_len) == PACKET_RCVD)
421 return 0;
422 goto out;
423 }
424
425 if (ipgre_rcv(skb, &tpi, hdr_len) == PACKET_RCVD)
426 return 0;
427
428out:
429 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PORT_UNREACH, 0);
430drop:
431 kfree_skb(skb);
432 return 0;
433}
434
435static void __gre_xmit(struct sk_buff *skb, struct net_device *dev,
436 const struct iphdr *tnl_params,
437 __be16 proto)
438{
439 struct ip_tunnel *tunnel = netdev_priv(dev);
440
441 if (tunnel->parms.o_flags & TUNNEL_SEQ)
442 tunnel->o_seqno++;
443
444 /* Push GRE header. */
445 gre_build_header(skb, tunnel->tun_hlen,
446 tunnel->parms.o_flags, proto, tunnel->parms.o_key,
447 htonl(tunnel->o_seqno));
448
449 ip_tunnel_xmit(skb, dev, tnl_params, tnl_params->protocol);
450}
451
452static int gre_handle_offloads(struct sk_buff *skb, bool csum)
453{
454 return iptunnel_handle_offloads(skb, csum ? SKB_GSO_GRE_CSUM : SKB_GSO_GRE);
455}
456
457static struct rtable *gre_get_rt(struct sk_buff *skb,
458 struct net_device *dev,
459 struct flowi4 *fl,
460 const struct ip_tunnel_key *key)
461{
462 struct net *net = dev_net(dev);
463
464 memset(fl, 0, sizeof(*fl));
465 fl->daddr = key->u.ipv4.dst;
466 fl->saddr = key->u.ipv4.src;
467 fl->flowi4_tos = RT_TOS(key->tos);
468 fl->flowi4_mark = skb->mark;
469 fl->flowi4_proto = IPPROTO_GRE;
470
471 return ip_route_output_key(net, fl);
472}
473
474static struct rtable *prepare_fb_xmit(struct sk_buff *skb,
475 struct net_device *dev,
476 struct flowi4 *fl,
477 int tunnel_hlen)
478{
479 struct ip_tunnel_info *tun_info;
480 const struct ip_tunnel_key *key;
481 struct rtable *rt = NULL;
482 int min_headroom;
483 bool use_cache;
484 int err;
485
486 tun_info = skb_tunnel_info(skb);
487 key = &tun_info->key;
488 use_cache = ip_tunnel_dst_cache_usable(skb, tun_info);
489
490 if (use_cache)
491 rt = dst_cache_get_ip4(&tun_info->dst_cache, &fl->saddr);
492 if (!rt) {
493 rt = gre_get_rt(skb, dev, fl, key);
494 if (IS_ERR(rt))
495 goto err_free_skb;
496 if (use_cache)
497 dst_cache_set_ip4(&tun_info->dst_cache, &rt->dst,
498 fl->saddr);
499 }
500
501 min_headroom = LL_RESERVED_SPACE(rt->dst.dev) + rt->dst.header_len
502 + tunnel_hlen + sizeof(struct iphdr);
503 if (skb_headroom(skb) < min_headroom || skb_header_cloned(skb)) {
504 int head_delta = SKB_DATA_ALIGN(min_headroom -
505 skb_headroom(skb) +
506 16);
507 err = pskb_expand_head(skb, max_t(int, head_delta, 0),
508 0, GFP_ATOMIC);
509 if (unlikely(err))
510 goto err_free_rt;
511 }
512 return rt;
513
514err_free_rt:
515 ip_rt_put(rt);
516err_free_skb:
517 kfree_skb(skb);
518 dev->stats.tx_dropped++;
519 return NULL;
520}
521
522static void gre_fb_xmit(struct sk_buff *skb, struct net_device *dev,
523 __be16 proto)
524{
525 struct ip_tunnel *tunnel = netdev_priv(dev);
526 struct ip_tunnel_info *tun_info;
527 const struct ip_tunnel_key *key;
528 struct rtable *rt = NULL;
529 struct flowi4 fl;
530 int tunnel_hlen;
531 __be16 df, flags;
532
533 tun_info = skb_tunnel_info(skb);
534 if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX) ||
535 ip_tunnel_info_af(tun_info) != AF_INET))
536 goto err_free_skb;
537
538 key = &tun_info->key;
539 tunnel_hlen = gre_calc_hlen(key->tun_flags);
540
541 rt = prepare_fb_xmit(skb, dev, &fl, tunnel_hlen);
542 if (!rt)
543 return;
544
545 /* Push Tunnel header. */
546 if (gre_handle_offloads(skb, !!(tun_info->key.tun_flags & TUNNEL_CSUM)))
547 goto err_free_rt;
548
549 flags = tun_info->key.tun_flags &
550 (TUNNEL_CSUM | TUNNEL_KEY | TUNNEL_SEQ);
551 gre_build_header(skb, tunnel_hlen, flags, proto,
552 tunnel_id_to_key32(tun_info->key.tun_id),
553 (flags & TUNNEL_SEQ) ? htonl(tunnel->o_seqno++) : 0);
554
555 df = key->tun_flags & TUNNEL_DONT_FRAGMENT ? htons(IP_DF) : 0;
556
557 iptunnel_xmit(skb->sk, rt, skb, fl.saddr, key->u.ipv4.dst, IPPROTO_GRE,
558 key->tos, key->ttl, df, false);
559 return;
560
561err_free_rt:
562 ip_rt_put(rt);
563err_free_skb:
564 kfree_skb(skb);
565 dev->stats.tx_dropped++;
566}
567
568static void erspan_fb_xmit(struct sk_buff *skb, struct net_device *dev,
569 __be16 proto)
570{
571 struct ip_tunnel *tunnel = netdev_priv(dev);
572 struct ip_tunnel_info *tun_info;
573 const struct ip_tunnel_key *key;
574 struct erspan_metadata *md;
575 struct rtable *rt = NULL;
576 bool truncate = false;
577 struct flowi4 fl;
578 int tunnel_hlen;
579 int version;
580 __be16 df;
581
582 tun_info = skb_tunnel_info(skb);
583 if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX) ||
584 ip_tunnel_info_af(tun_info) != AF_INET))
585 goto err_free_skb;
586
587 key = &tun_info->key;
588 md = ip_tunnel_info_opts(tun_info);
589 if (!md)
590 goto err_free_rt;
591
592 /* ERSPAN has fixed 8 byte GRE header */
593 version = md->version;
594 tunnel_hlen = 8 + erspan_hdr_len(version);
595
596 rt = prepare_fb_xmit(skb, dev, &fl, tunnel_hlen);
597 if (!rt)
598 return;
599
600 if (gre_handle_offloads(skb, false))
601 goto err_free_rt;
602
603 if (skb->len > dev->mtu + dev->hard_header_len) {
604 pskb_trim(skb, dev->mtu + dev->hard_header_len);
605 truncate = true;
606 }
607
608 if (version == 1) {
609 erspan_build_header(skb, ntohl(tunnel_id_to_key32(key->tun_id)),
610 ntohl(md->u.index), truncate, true);
611 } else if (version == 2) {
612 erspan_build_header_v2(skb,
613 ntohl(tunnel_id_to_key32(key->tun_id)),
614 md->u.md2.dir,
615 get_hwid(&md->u.md2),
616 truncate, true);
617 } else {
618 goto err_free_rt;
619 }
620
621 gre_build_header(skb, 8, TUNNEL_SEQ,
622 htons(ETH_P_ERSPAN), 0, htonl(tunnel->o_seqno++));
623
624 df = key->tun_flags & TUNNEL_DONT_FRAGMENT ? htons(IP_DF) : 0;
625
626 iptunnel_xmit(skb->sk, rt, skb, fl.saddr, key->u.ipv4.dst, IPPROTO_GRE,
627 key->tos, key->ttl, df, false);
628 return;
629
630err_free_rt:
631 ip_rt_put(rt);
632err_free_skb:
633 kfree_skb(skb);
634 dev->stats.tx_dropped++;
635}
636
637static int gre_fill_metadata_dst(struct net_device *dev, struct sk_buff *skb)
638{
639 struct ip_tunnel_info *info = skb_tunnel_info(skb);
640 struct rtable *rt;
641 struct flowi4 fl4;
642
643 if (ip_tunnel_info_af(info) != AF_INET)
644 return -EINVAL;
645
646 rt = gre_get_rt(skb, dev, &fl4, &info->key);
647 if (IS_ERR(rt))
648 return PTR_ERR(rt);
649
650 ip_rt_put(rt);
651 info->key.u.ipv4.src = fl4.saddr;
652 return 0;
653}
654
655static netdev_tx_t ipgre_xmit(struct sk_buff *skb,
656 struct net_device *dev)
657{
658 struct ip_tunnel *tunnel = netdev_priv(dev);
659 const struct iphdr *tnl_params;
660
661 if (tunnel->collect_md) {
662 gre_fb_xmit(skb, dev, skb->protocol);
663 return NETDEV_TX_OK;
664 }
665
666 if (dev->header_ops) {
667 /* Need space for new headers */
668 if (skb_cow_head(skb, dev->needed_headroom -
669 (tunnel->hlen + sizeof(struct iphdr))))
670 goto free_skb;
671
672 tnl_params = (const struct iphdr *)skb->data;
673
674 /* Pull skb since ip_tunnel_xmit() needs skb->data pointing
675 * to gre header.
676 */
677 skb_pull(skb, tunnel->hlen + sizeof(struct iphdr));
678 skb_reset_mac_header(skb);
679 } else {
680 if (skb_cow_head(skb, dev->needed_headroom))
681 goto free_skb;
682
683 tnl_params = &tunnel->parms.iph;
684 }
685
686 if (gre_handle_offloads(skb, !!(tunnel->parms.o_flags & TUNNEL_CSUM)))
687 goto free_skb;
688
689 __gre_xmit(skb, dev, tnl_params, skb->protocol);
690 return NETDEV_TX_OK;
691
692free_skb:
693 kfree_skb(skb);
694 dev->stats.tx_dropped++;
695 return NETDEV_TX_OK;
696}
697
698static netdev_tx_t erspan_xmit(struct sk_buff *skb,
699 struct net_device *dev)
700{
701 struct ip_tunnel *tunnel = netdev_priv(dev);
702 bool truncate = false;
703
704 if (tunnel->collect_md) {
705 erspan_fb_xmit(skb, dev, skb->protocol);
706 return NETDEV_TX_OK;
707 }
708
709 if (gre_handle_offloads(skb, false))
710 goto free_skb;
711
712 if (skb_cow_head(skb, dev->needed_headroom))
713 goto free_skb;
714
715 if (skb->len > dev->mtu + dev->hard_header_len) {
716 pskb_trim(skb, dev->mtu + dev->hard_header_len);
717 truncate = true;
718 }
719
720 /* Push ERSPAN header */
721 if (tunnel->erspan_ver == 1)
722 erspan_build_header(skb, ntohl(tunnel->parms.o_key),
723 tunnel->index,
724 truncate, true);
725 else if (tunnel->erspan_ver == 2)
726 erspan_build_header_v2(skb, ntohl(tunnel->parms.o_key),
727 tunnel->dir, tunnel->hwid,
728 truncate, true);
729 else
730 goto free_skb;
731
732 tunnel->parms.o_flags &= ~TUNNEL_KEY;
733 __gre_xmit(skb, dev, &tunnel->parms.iph, htons(ETH_P_ERSPAN));
734 return NETDEV_TX_OK;
735
736free_skb:
737 kfree_skb(skb);
738 dev->stats.tx_dropped++;
739 return NETDEV_TX_OK;
740}
741
742static netdev_tx_t gre_tap_xmit(struct sk_buff *skb,
743 struct net_device *dev)
744{
745 struct ip_tunnel *tunnel = netdev_priv(dev);
746
747 if (tunnel->collect_md) {
748 gre_fb_xmit(skb, dev, htons(ETH_P_TEB));
749 return NETDEV_TX_OK;
750 }
751
752 if (gre_handle_offloads(skb, !!(tunnel->parms.o_flags & TUNNEL_CSUM)))
753 goto free_skb;
754
755 if (skb_cow_head(skb, dev->needed_headroom))
756 goto free_skb;
757
758 __gre_xmit(skb, dev, &tunnel->parms.iph, htons(ETH_P_TEB));
759 return NETDEV_TX_OK;
760
761free_skb:
762 kfree_skb(skb);
763 dev->stats.tx_dropped++;
764 return NETDEV_TX_OK;
765}
766
767static void ipgre_link_update(struct net_device *dev, bool set_mtu)
768{
769 struct ip_tunnel *tunnel = netdev_priv(dev);
770 int len;
771
772 len = tunnel->tun_hlen;
773 tunnel->tun_hlen = gre_calc_hlen(tunnel->parms.o_flags);
774 len = tunnel->tun_hlen - len;
775 tunnel->hlen = tunnel->hlen + len;
776
777 dev->needed_headroom = dev->needed_headroom + len;
778 if (set_mtu)
779 dev->mtu = max_t(int, dev->mtu - len, 68);
780
781 if (!(tunnel->parms.o_flags & TUNNEL_SEQ)) {
782 if (!(tunnel->parms.o_flags & TUNNEL_CSUM) ||
783 tunnel->encap.type == TUNNEL_ENCAP_NONE) {
784 dev->features |= NETIF_F_GSO_SOFTWARE;
785 dev->hw_features |= NETIF_F_GSO_SOFTWARE;
786 } else {
787 dev->features &= ~NETIF_F_GSO_SOFTWARE;
788 dev->hw_features &= ~NETIF_F_GSO_SOFTWARE;
789 }
790 dev->features |= NETIF_F_LLTX;
791 } else {
792 dev->hw_features &= ~NETIF_F_GSO_SOFTWARE;
793 dev->features &= ~(NETIF_F_LLTX | NETIF_F_GSO_SOFTWARE);
794 }
795}
796
797static int ipgre_tunnel_ioctl(struct net_device *dev,
798 struct ifreq *ifr, int cmd)
799{
800 struct ip_tunnel_parm p;
801 int err;
802
803 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
804 return -EFAULT;
805
806 if (cmd == SIOCADDTUNNEL || cmd == SIOCCHGTUNNEL) {
807 if (p.iph.version != 4 || p.iph.protocol != IPPROTO_GRE ||
808 p.iph.ihl != 5 || (p.iph.frag_off & htons(~IP_DF)) ||
809 ((p.i_flags | p.o_flags) & (GRE_VERSION | GRE_ROUTING)))
810 return -EINVAL;
811 }
812
813 p.i_flags = gre_flags_to_tnl_flags(p.i_flags);
814 p.o_flags = gre_flags_to_tnl_flags(p.o_flags);
815
816 err = ip_tunnel_ioctl(dev, &p, cmd);
817 if (err)
818 return err;
819
820 if (cmd == SIOCCHGTUNNEL) {
821 struct ip_tunnel *t = netdev_priv(dev);
822
823 t->parms.i_flags = p.i_flags;
824 t->parms.o_flags = p.o_flags;
825
826 if (strcmp(dev->rtnl_link_ops->kind, "erspan"))
827 ipgre_link_update(dev, true);
828 }
829
830 p.i_flags = gre_tnl_flags_to_gre_flags(p.i_flags);
831 p.o_flags = gre_tnl_flags_to_gre_flags(p.o_flags);
832
833 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
834 return -EFAULT;
835
836 return 0;
837}
838
839/* Nice toy. Unfortunately, useless in real life :-)
840 It allows to construct virtual multiprotocol broadcast "LAN"
841 over the Internet, provided multicast routing is tuned.
842
843
844 I have no idea was this bicycle invented before me,
845 so that I had to set ARPHRD_IPGRE to a random value.
846 I have an impression, that Cisco could make something similar,
847 but this feature is apparently missing in IOS<=11.2(8).
848
849 I set up 10.66.66/24 and fec0:6666:6666::0/96 as virtual networks
850 with broadcast 224.66.66.66. If you have access to mbone, play with me :-)
851
852 ping -t 255 224.66.66.66
853
854 If nobody answers, mbone does not work.
855
856 ip tunnel add Universe mode gre remote 224.66.66.66 local <Your_real_addr> ttl 255
857 ip addr add 10.66.66.<somewhat>/24 dev Universe
858 ifconfig Universe up
859 ifconfig Universe add fe80::<Your_real_addr>/10
860 ifconfig Universe add fec0:6666:6666::<Your_real_addr>/96
861 ftp 10.66.66.66
862 ...
863 ftp fec0:6666:6666::193.233.7.65
864 ...
865 */
866static int ipgre_header(struct sk_buff *skb, struct net_device *dev,
867 unsigned short type,
868 const void *daddr, const void *saddr, unsigned int len)
869{
870 struct ip_tunnel *t = netdev_priv(dev);
871 struct iphdr *iph;
872 struct gre_base_hdr *greh;
873
874 iph = skb_push(skb, t->hlen + sizeof(*iph));
875 greh = (struct gre_base_hdr *)(iph+1);
876 greh->flags = gre_tnl_flags_to_gre_flags(t->parms.o_flags);
877 greh->protocol = htons(type);
878
879 memcpy(iph, &t->parms.iph, sizeof(struct iphdr));
880
881 /* Set the source hardware address. */
882 if (saddr)
883 memcpy(&iph->saddr, saddr, 4);
884 if (daddr)
885 memcpy(&iph->daddr, daddr, 4);
886 if (iph->daddr)
887 return t->hlen + sizeof(*iph);
888
889 return -(t->hlen + sizeof(*iph));
890}
891
892static int ipgre_header_parse(const struct sk_buff *skb, unsigned char *haddr)
893{
894 const struct iphdr *iph = (const struct iphdr *) skb_mac_header(skb);
895 memcpy(haddr, &iph->saddr, 4);
896 return 4;
897}
898
899static const struct header_ops ipgre_header_ops = {
900 .create = ipgre_header,
901 .parse = ipgre_header_parse,
902};
903
904#ifdef CONFIG_NET_IPGRE_BROADCAST
905static int ipgre_open(struct net_device *dev)
906{
907 struct ip_tunnel *t = netdev_priv(dev);
908
909 if (ipv4_is_multicast(t->parms.iph.daddr)) {
910 struct flowi4 fl4;
911 struct rtable *rt;
912
913 rt = ip_route_output_gre(t->net, &fl4,
914 t->parms.iph.daddr,
915 t->parms.iph.saddr,
916 t->parms.o_key,
917 RT_TOS(t->parms.iph.tos),
918 t->parms.link);
919 if (IS_ERR(rt))
920 return -EADDRNOTAVAIL;
921 dev = rt->dst.dev;
922 ip_rt_put(rt);
923 if (!__in_dev_get_rtnl(dev))
924 return -EADDRNOTAVAIL;
925 t->mlink = dev->ifindex;
926 ip_mc_inc_group(__in_dev_get_rtnl(dev), t->parms.iph.daddr);
927 }
928 return 0;
929}
930
931static int ipgre_close(struct net_device *dev)
932{
933 struct ip_tunnel *t = netdev_priv(dev);
934
935 if (ipv4_is_multicast(t->parms.iph.daddr) && t->mlink) {
936 struct in_device *in_dev;
937 in_dev = inetdev_by_index(t->net, t->mlink);
938 if (in_dev)
939 ip_mc_dec_group(in_dev, t->parms.iph.daddr);
940 }
941 return 0;
942}
943#endif
944
945static const struct net_device_ops ipgre_netdev_ops = {
946 .ndo_init = ipgre_tunnel_init,
947 .ndo_uninit = ip_tunnel_uninit,
948#ifdef CONFIG_NET_IPGRE_BROADCAST
949 .ndo_open = ipgre_open,
950 .ndo_stop = ipgre_close,
951#endif
952 .ndo_start_xmit = ipgre_xmit,
953 .ndo_do_ioctl = ipgre_tunnel_ioctl,
954 .ndo_change_mtu = ip_tunnel_change_mtu,
955 .ndo_get_stats64 = ip_tunnel_get_stats64,
956 .ndo_get_iflink = ip_tunnel_get_iflink,
957};
958
959#define GRE_FEATURES (NETIF_F_SG | \
960 NETIF_F_FRAGLIST | \
961 NETIF_F_HIGHDMA | \
962 NETIF_F_HW_CSUM)
963
964static void ipgre_tunnel_setup(struct net_device *dev)
965{
966 dev->netdev_ops = &ipgre_netdev_ops;
967 dev->type = ARPHRD_IPGRE;
968 ip_tunnel_setup(dev, ipgre_net_id);
969}
970
971static void __gre_tunnel_init(struct net_device *dev)
972{
973 struct ip_tunnel *tunnel;
974 int t_hlen;
975
976 tunnel = netdev_priv(dev);
977 tunnel->tun_hlen = gre_calc_hlen(tunnel->parms.o_flags);
978 tunnel->parms.iph.protocol = IPPROTO_GRE;
979
980 tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen;
981
982 t_hlen = tunnel->hlen + sizeof(struct iphdr);
983
984 dev->features |= GRE_FEATURES;
985 dev->hw_features |= GRE_FEATURES;
986
987 if (!(tunnel->parms.o_flags & TUNNEL_SEQ)) {
988 /* TCP offload with GRE SEQ is not supported, nor
989 * can we support 2 levels of outer headers requiring
990 * an update.
991 */
992 if (!(tunnel->parms.o_flags & TUNNEL_CSUM) ||
993 (tunnel->encap.type == TUNNEL_ENCAP_NONE)) {
994 dev->features |= NETIF_F_GSO_SOFTWARE;
995 dev->hw_features |= NETIF_F_GSO_SOFTWARE;
996 }
997
998 /* Can use a lockless transmit, unless we generate
999 * output sequences
1000 */
1001 dev->features |= NETIF_F_LLTX;
1002 }
1003}
1004
1005static int ipgre_tunnel_init(struct net_device *dev)
1006{
1007 struct ip_tunnel *tunnel = netdev_priv(dev);
1008 struct iphdr *iph = &tunnel->parms.iph;
1009
1010 __gre_tunnel_init(dev);
1011
1012 memcpy(dev->dev_addr, &iph->saddr, 4);
1013 memcpy(dev->broadcast, &iph->daddr, 4);
1014
1015 dev->flags = IFF_NOARP;
1016 netif_keep_dst(dev);
1017 dev->addr_len = 4;
1018
1019 if (iph->daddr && !tunnel->collect_md) {
1020#ifdef CONFIG_NET_IPGRE_BROADCAST
1021 if (ipv4_is_multicast(iph->daddr)) {
1022 if (!iph->saddr)
1023 return -EINVAL;
1024 dev->flags = IFF_BROADCAST;
1025 dev->header_ops = &ipgre_header_ops;
1026 }
1027#endif
1028 } else if (!tunnel->collect_md) {
1029 dev->header_ops = &ipgre_header_ops;
1030 }
1031
1032 return ip_tunnel_init(dev);
1033}
1034
1035static const struct gre_protocol ipgre_protocol = {
1036 .handler = gre_rcv,
1037 .err_handler = gre_err,
1038};
1039
1040static int __net_init ipgre_init_net(struct net *net)
1041{
1042 return ip_tunnel_init_net(net, ipgre_net_id, &ipgre_link_ops, NULL);
1043}
1044
1045static void __net_exit ipgre_exit_batch_net(struct list_head *list_net)
1046{
1047 ip_tunnel_delete_nets(list_net, ipgre_net_id, &ipgre_link_ops);
1048}
1049
1050static struct pernet_operations ipgre_net_ops = {
1051 .init = ipgre_init_net,
1052 .exit_batch = ipgre_exit_batch_net,
1053 .id = &ipgre_net_id,
1054 .size = sizeof(struct ip_tunnel_net),
1055};
1056
1057static int ipgre_tunnel_validate(struct nlattr *tb[], struct nlattr *data[],
1058 struct netlink_ext_ack *extack)
1059{
1060 __be16 flags;
1061
1062 if (!data)
1063 return 0;
1064
1065 flags = 0;
1066 if (data[IFLA_GRE_IFLAGS])
1067 flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]);
1068 if (data[IFLA_GRE_OFLAGS])
1069 flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]);
1070 if (flags & (GRE_VERSION|GRE_ROUTING))
1071 return -EINVAL;
1072
1073 if (data[IFLA_GRE_COLLECT_METADATA] &&
1074 data[IFLA_GRE_ENCAP_TYPE] &&
1075 nla_get_u16(data[IFLA_GRE_ENCAP_TYPE]) != TUNNEL_ENCAP_NONE)
1076 return -EINVAL;
1077
1078 return 0;
1079}
1080
1081static int ipgre_tap_validate(struct nlattr *tb[], struct nlattr *data[],
1082 struct netlink_ext_ack *extack)
1083{
1084 __be32 daddr;
1085
1086 if (tb[IFLA_ADDRESS]) {
1087 if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
1088 return -EINVAL;
1089 if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
1090 return -EADDRNOTAVAIL;
1091 }
1092
1093 if (!data)
1094 goto out;
1095
1096 if (data[IFLA_GRE_REMOTE]) {
1097 memcpy(&daddr, nla_data(data[IFLA_GRE_REMOTE]), 4);
1098 if (!daddr)
1099 return -EINVAL;
1100 }
1101
1102out:
1103 return ipgre_tunnel_validate(tb, data, extack);
1104}
1105
1106static int erspan_validate(struct nlattr *tb[], struct nlattr *data[],
1107 struct netlink_ext_ack *extack)
1108{
1109 __be16 flags = 0;
1110 int ret;
1111
1112 if (!data)
1113 return 0;
1114
1115 ret = ipgre_tap_validate(tb, data, extack);
1116 if (ret)
1117 return ret;
1118
1119 /* ERSPAN should only have GRE sequence and key flag */
1120 if (data[IFLA_GRE_OFLAGS])
1121 flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]);
1122 if (data[IFLA_GRE_IFLAGS])
1123 flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]);
1124 if (!data[IFLA_GRE_COLLECT_METADATA] &&
1125 flags != (GRE_SEQ | GRE_KEY))
1126 return -EINVAL;
1127
1128 /* ERSPAN Session ID only has 10-bit. Since we reuse
1129 * 32-bit key field as ID, check it's range.
1130 */
1131 if (data[IFLA_GRE_IKEY] &&
1132 (ntohl(nla_get_be32(data[IFLA_GRE_IKEY])) & ~ID_MASK))
1133 return -EINVAL;
1134
1135 if (data[IFLA_GRE_OKEY] &&
1136 (ntohl(nla_get_be32(data[IFLA_GRE_OKEY])) & ~ID_MASK))
1137 return -EINVAL;
1138
1139 return 0;
1140}
1141
1142static int ipgre_netlink_parms(struct net_device *dev,
1143 struct nlattr *data[],
1144 struct nlattr *tb[],
1145 struct ip_tunnel_parm *parms,
1146 __u32 *fwmark)
1147{
1148 struct ip_tunnel *t = netdev_priv(dev);
1149
1150 memset(parms, 0, sizeof(*parms));
1151
1152 parms->iph.protocol = IPPROTO_GRE;
1153
1154 if (!data)
1155 return 0;
1156
1157 if (data[IFLA_GRE_LINK])
1158 parms->link = nla_get_u32(data[IFLA_GRE_LINK]);
1159
1160 if (data[IFLA_GRE_IFLAGS])
1161 parms->i_flags = gre_flags_to_tnl_flags(nla_get_be16(data[IFLA_GRE_IFLAGS]));
1162
1163 if (data[IFLA_GRE_OFLAGS])
1164 parms->o_flags = gre_flags_to_tnl_flags(nla_get_be16(data[IFLA_GRE_OFLAGS]));
1165
1166 if (data[IFLA_GRE_IKEY])
1167 parms->i_key = nla_get_be32(data[IFLA_GRE_IKEY]);
1168
1169 if (data[IFLA_GRE_OKEY])
1170 parms->o_key = nla_get_be32(data[IFLA_GRE_OKEY]);
1171
1172 if (data[IFLA_GRE_LOCAL])
1173 parms->iph.saddr = nla_get_in_addr(data[IFLA_GRE_LOCAL]);
1174
1175 if (data[IFLA_GRE_REMOTE])
1176 parms->iph.daddr = nla_get_in_addr(data[IFLA_GRE_REMOTE]);
1177
1178 if (data[IFLA_GRE_TTL])
1179 parms->iph.ttl = nla_get_u8(data[IFLA_GRE_TTL]);
1180
1181 if (data[IFLA_GRE_TOS])
1182 parms->iph.tos = nla_get_u8(data[IFLA_GRE_TOS]);
1183
1184 if (!data[IFLA_GRE_PMTUDISC] || nla_get_u8(data[IFLA_GRE_PMTUDISC])) {
1185 if (t->ignore_df)
1186 return -EINVAL;
1187 parms->iph.frag_off = htons(IP_DF);
1188 }
1189
1190 if (data[IFLA_GRE_COLLECT_METADATA]) {
1191 t->collect_md = true;
1192 if (dev->type == ARPHRD_IPGRE)
1193 dev->type = ARPHRD_NONE;
1194 }
1195
1196 if (data[IFLA_GRE_IGNORE_DF]) {
1197 if (nla_get_u8(data[IFLA_GRE_IGNORE_DF])
1198 && (parms->iph.frag_off & htons(IP_DF)))
1199 return -EINVAL;
1200 t->ignore_df = !!nla_get_u8(data[IFLA_GRE_IGNORE_DF]);
1201 }
1202
1203 if (data[IFLA_GRE_FWMARK])
1204 *fwmark = nla_get_u32(data[IFLA_GRE_FWMARK]);
1205
1206 if (data[IFLA_GRE_ERSPAN_VER]) {
1207 t->erspan_ver = nla_get_u8(data[IFLA_GRE_ERSPAN_VER]);
1208
1209 if (t->erspan_ver != 1 && t->erspan_ver != 2)
1210 return -EINVAL;
1211 }
1212
1213 if (t->erspan_ver == 1) {
1214 if (data[IFLA_GRE_ERSPAN_INDEX]) {
1215 t->index = nla_get_u32(data[IFLA_GRE_ERSPAN_INDEX]);
1216 if (t->index & ~INDEX_MASK)
1217 return -EINVAL;
1218 }
1219 } else if (t->erspan_ver == 2) {
1220 if (data[IFLA_GRE_ERSPAN_DIR]) {
1221 t->dir = nla_get_u8(data[IFLA_GRE_ERSPAN_DIR]);
1222 if (t->dir & ~(DIR_MASK >> DIR_OFFSET))
1223 return -EINVAL;
1224 }
1225 if (data[IFLA_GRE_ERSPAN_HWID]) {
1226 t->hwid = nla_get_u16(data[IFLA_GRE_ERSPAN_HWID]);
1227 if (t->hwid & ~(HWID_MASK >> HWID_OFFSET))
1228 return -EINVAL;
1229 }
1230 }
1231
1232 return 0;
1233}
1234
1235/* This function returns true when ENCAP attributes are present in the nl msg */
1236static bool ipgre_netlink_encap_parms(struct nlattr *data[],
1237 struct ip_tunnel_encap *ipencap)
1238{
1239 bool ret = false;
1240
1241 memset(ipencap, 0, sizeof(*ipencap));
1242
1243 if (!data)
1244 return ret;
1245
1246 if (data[IFLA_GRE_ENCAP_TYPE]) {
1247 ret = true;
1248 ipencap->type = nla_get_u16(data[IFLA_GRE_ENCAP_TYPE]);
1249 }
1250
1251 if (data[IFLA_GRE_ENCAP_FLAGS]) {
1252 ret = true;
1253 ipencap->flags = nla_get_u16(data[IFLA_GRE_ENCAP_FLAGS]);
1254 }
1255
1256 if (data[IFLA_GRE_ENCAP_SPORT]) {
1257 ret = true;
1258 ipencap->sport = nla_get_be16(data[IFLA_GRE_ENCAP_SPORT]);
1259 }
1260
1261 if (data[IFLA_GRE_ENCAP_DPORT]) {
1262 ret = true;
1263 ipencap->dport = nla_get_be16(data[IFLA_GRE_ENCAP_DPORT]);
1264 }
1265
1266 return ret;
1267}
1268
1269static int gre_tap_init(struct net_device *dev)
1270{
1271 __gre_tunnel_init(dev);
1272 dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1273 netif_keep_dst(dev);
1274
1275 return ip_tunnel_init(dev);
1276}
1277
1278static const struct net_device_ops gre_tap_netdev_ops = {
1279 .ndo_init = gre_tap_init,
1280 .ndo_uninit = ip_tunnel_uninit,
1281 .ndo_start_xmit = gre_tap_xmit,
1282 .ndo_set_mac_address = eth_mac_addr,
1283 .ndo_validate_addr = eth_validate_addr,
1284 .ndo_change_mtu = ip_tunnel_change_mtu,
1285 .ndo_get_stats64 = ip_tunnel_get_stats64,
1286 .ndo_get_iflink = ip_tunnel_get_iflink,
1287 .ndo_fill_metadata_dst = gre_fill_metadata_dst,
1288};
1289
1290static int erspan_tunnel_init(struct net_device *dev)
1291{
1292 struct ip_tunnel *tunnel = netdev_priv(dev);
1293 int t_hlen;
1294
1295 tunnel->tun_hlen = 8;
1296 tunnel->parms.iph.protocol = IPPROTO_GRE;
1297 tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen +
1298 erspan_hdr_len(tunnel->erspan_ver);
1299 t_hlen = tunnel->hlen + sizeof(struct iphdr);
1300
1301 dev->features |= GRE_FEATURES;
1302 dev->hw_features |= GRE_FEATURES;
1303 dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1304 netif_keep_dst(dev);
1305
1306 return ip_tunnel_init(dev);
1307}
1308
1309static const struct net_device_ops erspan_netdev_ops = {
1310 .ndo_init = erspan_tunnel_init,
1311 .ndo_uninit = ip_tunnel_uninit,
1312 .ndo_start_xmit = erspan_xmit,
1313 .ndo_set_mac_address = eth_mac_addr,
1314 .ndo_validate_addr = eth_validate_addr,
1315 .ndo_change_mtu = ip_tunnel_change_mtu,
1316 .ndo_get_stats64 = ip_tunnel_get_stats64,
1317 .ndo_get_iflink = ip_tunnel_get_iflink,
1318 .ndo_fill_metadata_dst = gre_fill_metadata_dst,
1319};
1320
1321static void ipgre_tap_setup(struct net_device *dev)
1322{
1323 ether_setup(dev);
1324 dev->max_mtu = 0;
1325 dev->netdev_ops = &gre_tap_netdev_ops;
1326 dev->priv_flags &= ~IFF_TX_SKB_SHARING;
1327 dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1328 ip_tunnel_setup(dev, gre_tap_net_id);
1329}
1330
1331bool is_gretap_dev(const struct net_device *dev)
1332{
1333 return dev->netdev_ops == &gre_tap_netdev_ops;
1334}
1335EXPORT_SYMBOL_GPL(is_gretap_dev);
1336
1337static int ipgre_newlink(struct net *src_net, struct net_device *dev,
1338 struct nlattr *tb[], struct nlattr *data[],
1339 struct netlink_ext_ack *extack)
1340{
1341 struct ip_tunnel_parm p;
1342 struct ip_tunnel_encap ipencap;
1343 __u32 fwmark = 0;
1344 int err;
1345
1346 if (ipgre_netlink_encap_parms(data, &ipencap)) {
1347 struct ip_tunnel *t = netdev_priv(dev);
1348 err = ip_tunnel_encap_setup(t, &ipencap);
1349
1350 if (err < 0)
1351 return err;
1352 }
1353
1354 err = ipgre_netlink_parms(dev, data, tb, &p, &fwmark);
1355 if (err < 0)
1356 return err;
1357 return ip_tunnel_newlink(dev, tb, &p, fwmark);
1358}
1359
1360static int ipgre_changelink(struct net_device *dev, struct nlattr *tb[],
1361 struct nlattr *data[],
1362 struct netlink_ext_ack *extack)
1363{
1364 struct ip_tunnel *t = netdev_priv(dev);
1365 struct ip_tunnel_encap ipencap;
1366 __u32 fwmark = t->fwmark;
1367 struct ip_tunnel_parm p;
1368 int err;
1369
1370 if (ipgre_netlink_encap_parms(data, &ipencap)) {
1371 err = ip_tunnel_encap_setup(t, &ipencap);
1372
1373 if (err < 0)
1374 return err;
1375 }
1376
1377 err = ipgre_netlink_parms(dev, data, tb, &p, &fwmark);
1378 if (err < 0)
1379 return err;
1380
1381 err = ip_tunnel_changelink(dev, tb, &p, fwmark);
1382 if (err < 0)
1383 return err;
1384
1385 t->parms.i_flags = p.i_flags;
1386 t->parms.o_flags = p.o_flags;
1387
1388 if (strcmp(dev->rtnl_link_ops->kind, "erspan"))
1389 ipgre_link_update(dev, !tb[IFLA_MTU]);
1390
1391 return 0;
1392}
1393
1394static size_t ipgre_get_size(const struct net_device *dev)
1395{
1396 return
1397 /* IFLA_GRE_LINK */
1398 nla_total_size(4) +
1399 /* IFLA_GRE_IFLAGS */
1400 nla_total_size(2) +
1401 /* IFLA_GRE_OFLAGS */
1402 nla_total_size(2) +
1403 /* IFLA_GRE_IKEY */
1404 nla_total_size(4) +
1405 /* IFLA_GRE_OKEY */
1406 nla_total_size(4) +
1407 /* IFLA_GRE_LOCAL */
1408 nla_total_size(4) +
1409 /* IFLA_GRE_REMOTE */
1410 nla_total_size(4) +
1411 /* IFLA_GRE_TTL */
1412 nla_total_size(1) +
1413 /* IFLA_GRE_TOS */
1414 nla_total_size(1) +
1415 /* IFLA_GRE_PMTUDISC */
1416 nla_total_size(1) +
1417 /* IFLA_GRE_ENCAP_TYPE */
1418 nla_total_size(2) +
1419 /* IFLA_GRE_ENCAP_FLAGS */
1420 nla_total_size(2) +
1421 /* IFLA_GRE_ENCAP_SPORT */
1422 nla_total_size(2) +
1423 /* IFLA_GRE_ENCAP_DPORT */
1424 nla_total_size(2) +
1425 /* IFLA_GRE_COLLECT_METADATA */
1426 nla_total_size(0) +
1427 /* IFLA_GRE_IGNORE_DF */
1428 nla_total_size(1) +
1429 /* IFLA_GRE_FWMARK */
1430 nla_total_size(4) +
1431 /* IFLA_GRE_ERSPAN_INDEX */
1432 nla_total_size(4) +
1433 /* IFLA_GRE_ERSPAN_VER */
1434 nla_total_size(1) +
1435 /* IFLA_GRE_ERSPAN_DIR */
1436 nla_total_size(1) +
1437 /* IFLA_GRE_ERSPAN_HWID */
1438 nla_total_size(2) +
1439 0;
1440}
1441
1442static int ipgre_fill_info(struct sk_buff *skb, const struct net_device *dev)
1443{
1444 struct ip_tunnel *t = netdev_priv(dev);
1445 struct ip_tunnel_parm *p = &t->parms;
1446
1447 if (nla_put_u32(skb, IFLA_GRE_LINK, p->link) ||
1448 nla_put_be16(skb, IFLA_GRE_IFLAGS,
1449 gre_tnl_flags_to_gre_flags(p->i_flags)) ||
1450 nla_put_be16(skb, IFLA_GRE_OFLAGS,
1451 gre_tnl_flags_to_gre_flags(p->o_flags)) ||
1452 nla_put_be32(skb, IFLA_GRE_IKEY, p->i_key) ||
1453 nla_put_be32(skb, IFLA_GRE_OKEY, p->o_key) ||
1454 nla_put_in_addr(skb, IFLA_GRE_LOCAL, p->iph.saddr) ||
1455 nla_put_in_addr(skb, IFLA_GRE_REMOTE, p->iph.daddr) ||
1456 nla_put_u8(skb, IFLA_GRE_TTL, p->iph.ttl) ||
1457 nla_put_u8(skb, IFLA_GRE_TOS, p->iph.tos) ||
1458 nla_put_u8(skb, IFLA_GRE_PMTUDISC,
1459 !!(p->iph.frag_off & htons(IP_DF))) ||
1460 nla_put_u32(skb, IFLA_GRE_FWMARK, t->fwmark))
1461 goto nla_put_failure;
1462
1463 if (nla_put_u16(skb, IFLA_GRE_ENCAP_TYPE,
1464 t->encap.type) ||
1465 nla_put_be16(skb, IFLA_GRE_ENCAP_SPORT,
1466 t->encap.sport) ||
1467 nla_put_be16(skb, IFLA_GRE_ENCAP_DPORT,
1468 t->encap.dport) ||
1469 nla_put_u16(skb, IFLA_GRE_ENCAP_FLAGS,
1470 t->encap.flags))
1471 goto nla_put_failure;
1472
1473 if (nla_put_u8(skb, IFLA_GRE_IGNORE_DF, t->ignore_df))
1474 goto nla_put_failure;
1475
1476 if (t->collect_md) {
1477 if (nla_put_flag(skb, IFLA_GRE_COLLECT_METADATA))
1478 goto nla_put_failure;
1479 }
1480
1481 if (nla_put_u8(skb, IFLA_GRE_ERSPAN_VER, t->erspan_ver))
1482 goto nla_put_failure;
1483
1484 if (t->erspan_ver == 1) {
1485 if (nla_put_u32(skb, IFLA_GRE_ERSPAN_INDEX, t->index))
1486 goto nla_put_failure;
1487 } else if (t->erspan_ver == 2) {
1488 if (nla_put_u8(skb, IFLA_GRE_ERSPAN_DIR, t->dir))
1489 goto nla_put_failure;
1490 if (nla_put_u16(skb, IFLA_GRE_ERSPAN_HWID, t->hwid))
1491 goto nla_put_failure;
1492 }
1493
1494 return 0;
1495
1496nla_put_failure:
1497 return -EMSGSIZE;
1498}
1499
1500static void erspan_setup(struct net_device *dev)
1501{
1502 ether_setup(dev);
1503 dev->netdev_ops = &erspan_netdev_ops;
1504 dev->priv_flags &= ~IFF_TX_SKB_SHARING;
1505 dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1506 ip_tunnel_setup(dev, erspan_net_id);
1507}
1508
1509static const struct nla_policy ipgre_policy[IFLA_GRE_MAX + 1] = {
1510 [IFLA_GRE_LINK] = { .type = NLA_U32 },
1511 [IFLA_GRE_IFLAGS] = { .type = NLA_U16 },
1512 [IFLA_GRE_OFLAGS] = { .type = NLA_U16 },
1513 [IFLA_GRE_IKEY] = { .type = NLA_U32 },
1514 [IFLA_GRE_OKEY] = { .type = NLA_U32 },
1515 [IFLA_GRE_LOCAL] = { .len = FIELD_SIZEOF(struct iphdr, saddr) },
1516 [IFLA_GRE_REMOTE] = { .len = FIELD_SIZEOF(struct iphdr, daddr) },
1517 [IFLA_GRE_TTL] = { .type = NLA_U8 },
1518 [IFLA_GRE_TOS] = { .type = NLA_U8 },
1519 [IFLA_GRE_PMTUDISC] = { .type = NLA_U8 },
1520 [IFLA_GRE_ENCAP_TYPE] = { .type = NLA_U16 },
1521 [IFLA_GRE_ENCAP_FLAGS] = { .type = NLA_U16 },
1522 [IFLA_GRE_ENCAP_SPORT] = { .type = NLA_U16 },
1523 [IFLA_GRE_ENCAP_DPORT] = { .type = NLA_U16 },
1524 [IFLA_GRE_COLLECT_METADATA] = { .type = NLA_FLAG },
1525 [IFLA_GRE_IGNORE_DF] = { .type = NLA_U8 },
1526 [IFLA_GRE_FWMARK] = { .type = NLA_U32 },
1527 [IFLA_GRE_ERSPAN_INDEX] = { .type = NLA_U32 },
1528 [IFLA_GRE_ERSPAN_VER] = { .type = NLA_U8 },
1529 [IFLA_GRE_ERSPAN_DIR] = { .type = NLA_U8 },
1530 [IFLA_GRE_ERSPAN_HWID] = { .type = NLA_U16 },
1531};
1532
1533static struct rtnl_link_ops ipgre_link_ops __read_mostly = {
1534 .kind = "gre",
1535 .maxtype = IFLA_GRE_MAX,
1536 .policy = ipgre_policy,
1537 .priv_size = sizeof(struct ip_tunnel),
1538 .setup = ipgre_tunnel_setup,
1539 .validate = ipgre_tunnel_validate,
1540 .newlink = ipgre_newlink,
1541 .changelink = ipgre_changelink,
1542 .dellink = ip_tunnel_dellink,
1543 .get_size = ipgre_get_size,
1544 .fill_info = ipgre_fill_info,
1545 .get_link_net = ip_tunnel_get_link_net,
1546};
1547
1548static struct rtnl_link_ops ipgre_tap_ops __read_mostly = {
1549 .kind = "gretap",
1550 .maxtype = IFLA_GRE_MAX,
1551 .policy = ipgre_policy,
1552 .priv_size = sizeof(struct ip_tunnel),
1553 .setup = ipgre_tap_setup,
1554 .validate = ipgre_tap_validate,
1555 .newlink = ipgre_newlink,
1556 .changelink = ipgre_changelink,
1557 .dellink = ip_tunnel_dellink,
1558 .get_size = ipgre_get_size,
1559 .fill_info = ipgre_fill_info,
1560 .get_link_net = ip_tunnel_get_link_net,
1561};
1562
1563static struct rtnl_link_ops erspan_link_ops __read_mostly = {
1564 .kind = "erspan",
1565 .maxtype = IFLA_GRE_MAX,
1566 .policy = ipgre_policy,
1567 .priv_size = sizeof(struct ip_tunnel),
1568 .setup = erspan_setup,
1569 .validate = erspan_validate,
1570 .newlink = ipgre_newlink,
1571 .changelink = ipgre_changelink,
1572 .dellink = ip_tunnel_dellink,
1573 .get_size = ipgre_get_size,
1574 .fill_info = ipgre_fill_info,
1575 .get_link_net = ip_tunnel_get_link_net,
1576};
1577
1578struct net_device *gretap_fb_dev_create(struct net *net, const char *name,
1579 u8 name_assign_type)
1580{
1581 struct nlattr *tb[IFLA_MAX + 1];
1582 struct net_device *dev;
1583 LIST_HEAD(list_kill);
1584 struct ip_tunnel *t;
1585 int err;
1586
1587 memset(&tb, 0, sizeof(tb));
1588
1589 dev = rtnl_create_link(net, name, name_assign_type,
1590 &ipgre_tap_ops, tb);
1591 if (IS_ERR(dev))
1592 return dev;
1593
1594 /* Configure flow based GRE device. */
1595 t = netdev_priv(dev);
1596 t->collect_md = true;
1597
1598 err = ipgre_newlink(net, dev, tb, NULL, NULL);
1599 if (err < 0) {
1600 free_netdev(dev);
1601 return ERR_PTR(err);
1602 }
1603
1604 /* openvswitch users expect packet sizes to be unrestricted,
1605 * so set the largest MTU we can.
1606 */
1607 err = __ip_tunnel_change_mtu(dev, IP_MAX_MTU, false);
1608 if (err)
1609 goto out;
1610
1611 err = rtnl_configure_link(dev, NULL);
1612 if (err < 0)
1613 goto out;
1614
1615 return dev;
1616out:
1617 ip_tunnel_dellink(dev, &list_kill);
1618 unregister_netdevice_many(&list_kill);
1619 return ERR_PTR(err);
1620}
1621EXPORT_SYMBOL_GPL(gretap_fb_dev_create);
1622
1623static int __net_init ipgre_tap_init_net(struct net *net)
1624{
1625 return ip_tunnel_init_net(net, gre_tap_net_id, &ipgre_tap_ops, "gretap0");
1626}
1627
1628static void __net_exit ipgre_tap_exit_batch_net(struct list_head *list_net)
1629{
1630 ip_tunnel_delete_nets(list_net, gre_tap_net_id, &ipgre_tap_ops);
1631}
1632
1633static struct pernet_operations ipgre_tap_net_ops = {
1634 .init = ipgre_tap_init_net,
1635 .exit_batch = ipgre_tap_exit_batch_net,
1636 .id = &gre_tap_net_id,
1637 .size = sizeof(struct ip_tunnel_net),
1638};
1639
1640static int __net_init erspan_init_net(struct net *net)
1641{
1642 return ip_tunnel_init_net(net, erspan_net_id,
1643 &erspan_link_ops, "erspan0");
1644}
1645
1646static void __net_exit erspan_exit_batch_net(struct list_head *net_list)
1647{
1648 ip_tunnel_delete_nets(net_list, erspan_net_id, &erspan_link_ops);
1649}
1650
1651static struct pernet_operations erspan_net_ops = {
1652 .init = erspan_init_net,
1653 .exit_batch = erspan_exit_batch_net,
1654 .id = &erspan_net_id,
1655 .size = sizeof(struct ip_tunnel_net),
1656};
1657
1658static int __init ipgre_init(void)
1659{
1660 int err;
1661
1662 pr_info("GRE over IPv4 tunneling driver\n");
1663
1664 err = register_pernet_device(&ipgre_net_ops);
1665 if (err < 0)
1666 return err;
1667
1668 err = register_pernet_device(&ipgre_tap_net_ops);
1669 if (err < 0)
1670 goto pnet_tap_failed;
1671
1672 err = register_pernet_device(&erspan_net_ops);
1673 if (err < 0)
1674 goto pnet_erspan_failed;
1675
1676 err = gre_add_protocol(&ipgre_protocol, GREPROTO_CISCO);
1677 if (err < 0) {
1678 pr_info("%s: can't add protocol\n", __func__);
1679 goto add_proto_failed;
1680 }
1681
1682 err = rtnl_link_register(&ipgre_link_ops);
1683 if (err < 0)
1684 goto rtnl_link_failed;
1685
1686 err = rtnl_link_register(&ipgre_tap_ops);
1687 if (err < 0)
1688 goto tap_ops_failed;
1689
1690 err = rtnl_link_register(&erspan_link_ops);
1691 if (err < 0)
1692 goto erspan_link_failed;
1693
1694 return 0;
1695
1696erspan_link_failed:
1697 rtnl_link_unregister(&ipgre_tap_ops);
1698tap_ops_failed:
1699 rtnl_link_unregister(&ipgre_link_ops);
1700rtnl_link_failed:
1701 gre_del_protocol(&ipgre_protocol, GREPROTO_CISCO);
1702add_proto_failed:
1703 unregister_pernet_device(&erspan_net_ops);
1704pnet_erspan_failed:
1705 unregister_pernet_device(&ipgre_tap_net_ops);
1706pnet_tap_failed:
1707 unregister_pernet_device(&ipgre_net_ops);
1708 return err;
1709}
1710
1711static void __exit ipgre_fini(void)
1712{
1713 rtnl_link_unregister(&ipgre_tap_ops);
1714 rtnl_link_unregister(&ipgre_link_ops);
1715 rtnl_link_unregister(&erspan_link_ops);
1716 gre_del_protocol(&ipgre_protocol, GREPROTO_CISCO);
1717 unregister_pernet_device(&ipgre_tap_net_ops);
1718 unregister_pernet_device(&ipgre_net_ops);
1719 unregister_pernet_device(&erspan_net_ops);
1720}
1721
1722module_init(ipgre_init);
1723module_exit(ipgre_fini);
1724MODULE_LICENSE("GPL");
1725MODULE_ALIAS_RTNL_LINK("gre");
1726MODULE_ALIAS_RTNL_LINK("gretap");
1727MODULE_ALIAS_RTNL_LINK("erspan");
1728MODULE_ALIAS_NETDEV("gre0");
1729MODULE_ALIAS_NETDEV("gretap0");
1730MODULE_ALIAS_NETDEV("erspan0");