1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Linux NET3: GRE over IP protocol decoder.
4 *
5 * Authors: Alexey Kuznetsov (kuznet@ms2.inr.ac.ru)
6 */
7
8 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
9
10 #include <linux/capability.h>
11 #include <linux/module.h>
12 #include <linux/types.h>
13 #include <linux/kernel.h>
14 #include <linux/slab.h>
15 #include <linux/uaccess.h>
16 #include <linux/skbuff.h>
17 #include <linux/netdevice.h>
18 #include <linux/in.h>
19 #include <linux/tcp.h>
20 #include <linux/udp.h>
21 #include <linux/if_arp.h>
22 #include <linux/if_vlan.h>
23 #include <linux/init.h>
24 #include <linux/in6.h>
25 #include <linux/inetdevice.h>
26 #include <linux/igmp.h>
27 #include <linux/netfilter_ipv4.h>
28 #include <linux/etherdevice.h>
29 #include <linux/if_ether.h>
30
31 #include <net/sock.h>
32 #include <net/ip.h>
33 #include <net/icmp.h>
34 #include <net/protocol.h>
35 #include <net/ip_tunnels.h>
36 #include <net/arp.h>
37 #include <net/checksum.h>
38 #include <net/dsfield.h>
39 #include <net/inet_ecn.h>
40 #include <net/xfrm.h>
41 #include <net/net_namespace.h>
42 #include <net/netns/generic.h>
43 #include <net/rtnetlink.h>
44 #include <net/gre.h>
45 #include <net/dst_metadata.h>
46 #include <net/erspan.h>
47
48 /*
49 Problems & solutions
50 --------------------
51
52 1. The most important issue is detecting local dead loops.
53 They would cause complete host lockup in transmit, which
54 would be "resolved" by stack overflow or, if queueing is enabled,
55 with infinite looping in net_bh.
56
57 We cannot track such dead loops during route installation,
58 it is infeasible task. The most general solutions would be
59 to keep skb->encapsulation counter (sort of local ttl),
60 and silently drop packet when it expires. It is a good
61 solution, but it supposes maintaining new variable in ALL
62 skb, even if no tunneling is used.
63
64 Current solution: xmit_recursion breaks dead loops. This is a percpu
65 counter, since when we enter the first ndo_xmit(), cpu migration is
66 forbidden. We force an exit if this counter reaches RECURSION_LIMIT
67
68 2. Networking dead loops would not kill routers, but would really
69 kill network. IP hop limit plays role of "t->recursion" in this case,
70 if we copy it from packet being encapsulated to upper header.
71 It is very good solution, but it introduces two problems:
72
73 - Routing protocols, using packets with ttl=1 (OSPF, RIP2),
74 do not work over tunnels.
75 - traceroute does not work. I planned to relay ICMP from tunnel,
76 so that this problem would be solved and traceroute output
77 would even more informative. This idea appeared to be wrong:
78 only Linux complies to rfc1812 now (yes, guys, Linux is the only
79 true router now :-)), all routers (at least, in neighbourhood of mine)
80 return only 8 bytes of payload. It is the end.
81
82 Hence, if we want that OSPF worked or traceroute said something reasonable,
83 we should search for another solution.
84
85 One of them is to parse packet trying to detect inner encapsulation
86 made by our node. It is difficult or even impossible, especially,
87 taking into account fragmentation. TO be short, ttl is not solution at all.
88
89 Current solution: The solution was UNEXPECTEDLY SIMPLE.
90 We force DF flag on tunnels with preconfigured hop limit,
91 that is ALL. :-) Well, it does not remove the problem completely,
92 but exponential growth of network traffic is changed to linear
93 (branches, that exceed pmtu are pruned) and tunnel mtu
94 rapidly degrades to value <68, where looping stops.
95 Yes, it is not good if there exists a router in the loop,
96 which does not force DF, even when encapsulating packets have DF set.
97 But it is not our problem! Nobody could accuse us, we made
98 all that we could make. Even if it is your gated who injected
99 fatal route to network, even if it were you who configured
100 fatal static route: you are innocent. :-)
101
102 Alexey Kuznetsov.
103 */
104
105 static bool log_ecn_error = true;
106 module_param(log_ecn_error, bool, 0644);
107 MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN");
108
109 static struct rtnl_link_ops ipgre_link_ops __read_mostly;
110 static const struct header_ops ipgre_header_ops;
111
112 static int ipgre_tunnel_init(struct net_device *dev);
113 static void erspan_build_header(struct sk_buff *skb,
114 u32 id, u32 index,
115 bool truncate, bool is_ipv4);
116
117 static unsigned int ipgre_net_id __read_mostly;
118 static unsigned int gre_tap_net_id __read_mostly;
119 static unsigned int erspan_net_id __read_mostly;
120
ipgre_err(struct sk_buff * skb,u32 info,const struct tnl_ptk_info * tpi)121 static int ipgre_err(struct sk_buff *skb, u32 info,
122 const struct tnl_ptk_info *tpi)
123 {
124
125 /* All the routers (except for Linux) return only
126 8 bytes of packet payload. It means, that precise relaying of
127 ICMP in the real Internet is absolutely infeasible.
128
129 Moreover, Cisco "wise men" put GRE key to the third word
130 in GRE header. It makes impossible maintaining even soft
131 state for keyed GRE tunnels with enabled checksum. Tell
132 them "thank you".
133
134 Well, I wonder, rfc1812 was written by Cisco employee,
135 what the hell these idiots break standards established
136 by themselves???
137 */
138 struct net *net = dev_net(skb->dev);
139 struct ip_tunnel_net *itn;
140 const struct iphdr *iph;
141 const int type = icmp_hdr(skb)->type;
142 const int code = icmp_hdr(skb)->code;
143 unsigned int data_len = 0;
144 struct ip_tunnel *t;
145
146 if (tpi->proto == htons(ETH_P_TEB))
147 itn = net_generic(net, gre_tap_net_id);
148 else if (tpi->proto == htons(ETH_P_ERSPAN) ||
149 tpi->proto == htons(ETH_P_ERSPAN2))
150 itn = net_generic(net, erspan_net_id);
151 else
152 itn = net_generic(net, ipgre_net_id);
153
154 iph = (const struct iphdr *)(icmp_hdr(skb) + 1);
155 t = ip_tunnel_lookup(itn, skb->dev->ifindex, tpi->flags,
156 iph->daddr, iph->saddr, tpi->key);
157
158 if (!t)
159 return -ENOENT;
160
161 switch (type) {
162 default:
163 case ICMP_PARAMETERPROB:
164 return 0;
165
166 case ICMP_DEST_UNREACH:
167 switch (code) {
168 case ICMP_SR_FAILED:
169 case ICMP_PORT_UNREACH:
170 /* Impossible event. */
171 return 0;
172 default:
173 /* All others are translated to HOST_UNREACH.
174 rfc2003 contains "deep thoughts" about NET_UNREACH,
175 I believe they are just ether pollution. --ANK
176 */
177 break;
178 }
179 break;
180
181 case ICMP_TIME_EXCEEDED:
182 if (code != ICMP_EXC_TTL)
183 return 0;
184 data_len = icmp_hdr(skb)->un.reserved[1] * 4; /* RFC 4884 4.1 */
185 break;
186
187 case ICMP_REDIRECT:
188 break;
189 }
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 0;
196 #endif
197
198 if (t->parms.iph.daddr == 0 ||
199 ipv4_is_multicast(t->parms.iph.daddr))
200 return 0;
201
202 if (t->parms.iph.ttl == 0 && type == ICMP_TIME_EXCEEDED)
203 return 0;
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 return 0;
212 }
213
gre_err(struct sk_buff * skb,u32 info)214 static void gre_err(struct sk_buff *skb, u32 info)
215 {
216 /* All the routers (except for Linux) return only
217 * 8 bytes of packet payload. It means, that precise relaying of
218 * ICMP in the real Internet is absolutely infeasible.
219 *
220 * Moreover, Cisco "wise men" put GRE key to the third word
221 * in GRE header. It makes impossible maintaining even soft
222 * state for keyed
223 * GRE tunnels with enabled checksum. Tell them "thank you".
224 *
225 * Well, I wonder, rfc1812 was written by Cisco employee,
226 * what the hell these idiots break standards established
227 * by themselves???
228 */
229
230 const struct iphdr *iph = (struct iphdr *)skb->data;
231 const int type = icmp_hdr(skb)->type;
232 const int code = icmp_hdr(skb)->code;
233 struct tnl_ptk_info tpi;
234
235 if (gre_parse_header(skb, &tpi, NULL, htons(ETH_P_IP),
236 iph->ihl * 4) < 0)
237 return;
238
239 if (type == ICMP_DEST_UNREACH && code == ICMP_FRAG_NEEDED) {
240 ipv4_update_pmtu(skb, dev_net(skb->dev), info,
241 skb->dev->ifindex, IPPROTO_GRE);
242 return;
243 }
244 if (type == ICMP_REDIRECT) {
245 ipv4_redirect(skb, dev_net(skb->dev), skb->dev->ifindex,
246 IPPROTO_GRE);
247 return;
248 }
249
250 ipgre_err(skb, info, &tpi);
251 }
252
is_erspan_type1(int gre_hdr_len)253 static bool is_erspan_type1(int gre_hdr_len)
254 {
255 /* Both ERSPAN type I (version 0) and type II (version 1) use
256 * protocol 0x88BE, but the type I has only 4-byte GRE header,
257 * while type II has 8-byte.
258 */
259 return gre_hdr_len == 4;
260 }
261
erspan_rcv(struct sk_buff * skb,struct tnl_ptk_info * tpi,int gre_hdr_len)262 static int erspan_rcv(struct sk_buff *skb, struct tnl_ptk_info *tpi,
263 int gre_hdr_len)
264 {
265 struct net *net = dev_net(skb->dev);
266 struct metadata_dst *tun_dst = NULL;
267 struct erspan_base_hdr *ershdr;
268 struct ip_tunnel_net *itn;
269 struct ip_tunnel *tunnel;
270 const struct iphdr *iph;
271 struct erspan_md2 *md2;
272 int ver;
273 int len;
274
275 itn = net_generic(net, erspan_net_id);
276 iph = ip_hdr(skb);
277 if (is_erspan_type1(gre_hdr_len)) {
278 ver = 0;
279 tunnel = ip_tunnel_lookup(itn, skb->dev->ifindex,
280 tpi->flags | TUNNEL_NO_KEY,
281 iph->saddr, iph->daddr, 0);
282 } else {
283 ershdr = (struct erspan_base_hdr *)(skb->data + gre_hdr_len);
284 ver = ershdr->ver;
285 tunnel = ip_tunnel_lookup(itn, skb->dev->ifindex,
286 tpi->flags | TUNNEL_KEY,
287 iph->saddr, iph->daddr, tpi->key);
288 }
289
290 if (tunnel) {
291 if (is_erspan_type1(gre_hdr_len))
292 len = gre_hdr_len;
293 else
294 len = gre_hdr_len + erspan_hdr_len(ver);
295
296 if (unlikely(!pskb_may_pull(skb, len)))
297 return PACKET_REJECT;
298
299 if (__iptunnel_pull_header(skb,
300 len,
301 htons(ETH_P_TEB),
302 false, false) < 0)
303 goto drop;
304
305 if (tunnel->collect_md) {
306 struct erspan_metadata *pkt_md, *md;
307 struct ip_tunnel_info *info;
308 unsigned char *gh;
309 __be64 tun_id;
310 __be16 flags;
311
312 tpi->flags |= TUNNEL_KEY;
313 flags = tpi->flags;
314 tun_id = key32_to_tunnel_id(tpi->key);
315
316 tun_dst = ip_tun_rx_dst(skb, flags,
317 tun_id, sizeof(*md));
318 if (!tun_dst)
319 return PACKET_REJECT;
320
321 /* skb can be uncloned in __iptunnel_pull_header, so
322 * old pkt_md is no longer valid and we need to reset
323 * it
324 */
325 gh = skb_network_header(skb) +
326 skb_network_header_len(skb);
327 pkt_md = (struct erspan_metadata *)(gh + gre_hdr_len +
328 sizeof(*ershdr));
329 md = ip_tunnel_info_opts(&tun_dst->u.tun_info);
330 md->version = ver;
331 md2 = &md->u.md2;
332 memcpy(md2, pkt_md, ver == 1 ? ERSPAN_V1_MDSIZE :
333 ERSPAN_V2_MDSIZE);
334
335 info = &tun_dst->u.tun_info;
336 info->key.tun_flags |= TUNNEL_ERSPAN_OPT;
337 info->options_len = sizeof(*md);
338 }
339
340 skb_reset_mac_header(skb);
341 ip_tunnel_rcv(tunnel, skb, tpi, tun_dst, log_ecn_error);
342 return PACKET_RCVD;
343 }
344 return PACKET_REJECT;
345
346 drop:
347 kfree_skb(skb);
348 return PACKET_RCVD;
349 }
350
__ipgre_rcv(struct sk_buff * skb,const struct tnl_ptk_info * tpi,struct ip_tunnel_net * itn,int hdr_len,bool raw_proto)351 static int __ipgre_rcv(struct sk_buff *skb, const struct tnl_ptk_info *tpi,
352 struct ip_tunnel_net *itn, int hdr_len, bool raw_proto)
353 {
354 struct metadata_dst *tun_dst = NULL;
355 const struct iphdr *iph;
356 struct ip_tunnel *tunnel;
357
358 iph = ip_hdr(skb);
359 tunnel = ip_tunnel_lookup(itn, skb->dev->ifindex, tpi->flags,
360 iph->saddr, iph->daddr, tpi->key);
361
362 if (tunnel) {
363 const struct iphdr *tnl_params;
364
365 if (__iptunnel_pull_header(skb, hdr_len, tpi->proto,
366 raw_proto, false) < 0)
367 goto drop;
368
369 /* Special case for ipgre_header_parse(), which expects the
370 * mac_header to point to the outer IP header.
371 */
372 if (tunnel->dev->header_ops == &ipgre_header_ops)
373 skb_pop_mac_header(skb);
374 else
375 skb_reset_mac_header(skb);
376
377 tnl_params = &tunnel->parms.iph;
378 if (tunnel->collect_md || tnl_params->daddr == 0) {
379 __be16 flags;
380 __be64 tun_id;
381
382 flags = tpi->flags & (TUNNEL_CSUM | TUNNEL_KEY);
383 tun_id = key32_to_tunnel_id(tpi->key);
384 tun_dst = ip_tun_rx_dst(skb, flags, tun_id, 0);
385 if (!tun_dst)
386 return PACKET_REJECT;
387 }
388
389 ip_tunnel_rcv(tunnel, skb, tpi, tun_dst, log_ecn_error);
390 return PACKET_RCVD;
391 }
392 return PACKET_NEXT;
393
394 drop:
395 kfree_skb(skb);
396 return PACKET_RCVD;
397 }
398
ipgre_rcv(struct sk_buff * skb,const struct tnl_ptk_info * tpi,int hdr_len)399 static int ipgre_rcv(struct sk_buff *skb, const struct tnl_ptk_info *tpi,
400 int hdr_len)
401 {
402 struct net *net = dev_net(skb->dev);
403 struct ip_tunnel_net *itn;
404 int res;
405
406 if (tpi->proto == htons(ETH_P_TEB))
407 itn = net_generic(net, gre_tap_net_id);
408 else
409 itn = net_generic(net, ipgre_net_id);
410
411 res = __ipgre_rcv(skb, tpi, itn, hdr_len, false);
412 if (res == PACKET_NEXT && tpi->proto == htons(ETH_P_TEB)) {
413 /* ipgre tunnels in collect metadata mode should receive
414 * also ETH_P_TEB traffic.
415 */
416 itn = net_generic(net, ipgre_net_id);
417 res = __ipgre_rcv(skb, tpi, itn, hdr_len, true);
418 }
419 return res;
420 }
421
gre_rcv(struct sk_buff * skb)422 static int gre_rcv(struct sk_buff *skb)
423 {
424 struct tnl_ptk_info tpi;
425 bool csum_err = false;
426 int hdr_len;
427
428 #ifdef CONFIG_NET_IPGRE_BROADCAST
429 if (ipv4_is_multicast(ip_hdr(skb)->daddr)) {
430 /* Looped back packet, drop it! */
431 if (rt_is_output_route(skb_rtable(skb)))
432 goto drop;
433 }
434 #endif
435
436 hdr_len = gre_parse_header(skb, &tpi, &csum_err, htons(ETH_P_IP), 0);
437 if (hdr_len < 0)
438 goto drop;
439
440 if (unlikely(tpi.proto == htons(ETH_P_ERSPAN) ||
441 tpi.proto == htons(ETH_P_ERSPAN2))) {
442 if (erspan_rcv(skb, &tpi, hdr_len) == PACKET_RCVD)
443 return 0;
444 goto out;
445 }
446
447 if (ipgre_rcv(skb, &tpi, hdr_len) == PACKET_RCVD)
448 return 0;
449
450 out:
451 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PORT_UNREACH, 0);
452 drop:
453 kfree_skb(skb);
454 return 0;
455 }
456
__gre_xmit(struct sk_buff * skb,struct net_device * dev,const struct iphdr * tnl_params,__be16 proto)457 static void __gre_xmit(struct sk_buff *skb, struct net_device *dev,
458 const struct iphdr *tnl_params,
459 __be16 proto)
460 {
461 struct ip_tunnel *tunnel = netdev_priv(dev);
462 __be16 flags = tunnel->parms.o_flags;
463
464 /* Push GRE header. */
465 gre_build_header(skb, tunnel->tun_hlen,
466 flags, proto, tunnel->parms.o_key,
467 (flags & TUNNEL_SEQ) ? htonl(atomic_fetch_inc(&tunnel->o_seqno)) : 0);
468
469 ip_tunnel_xmit(skb, dev, tnl_params, tnl_params->protocol);
470 }
471
gre_handle_offloads(struct sk_buff * skb,bool csum)472 static int gre_handle_offloads(struct sk_buff *skb, bool csum)
473 {
474 return iptunnel_handle_offloads(skb, csum ? SKB_GSO_GRE_CSUM : SKB_GSO_GRE);
475 }
476
gre_fb_xmit(struct sk_buff * skb,struct net_device * dev,__be16 proto)477 static void gre_fb_xmit(struct sk_buff *skb, struct net_device *dev,
478 __be16 proto)
479 {
480 struct ip_tunnel *tunnel = netdev_priv(dev);
481 struct ip_tunnel_info *tun_info;
482 const struct ip_tunnel_key *key;
483 int tunnel_hlen;
484 __be16 flags;
485
486 tun_info = skb_tunnel_info(skb);
487 if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX) ||
488 ip_tunnel_info_af(tun_info) != AF_INET))
489 goto err_free_skb;
490
491 key = &tun_info->key;
492 tunnel_hlen = gre_calc_hlen(key->tun_flags);
493
494 if (skb_cow_head(skb, dev->needed_headroom))
495 goto err_free_skb;
496
497 /* Push Tunnel header. */
498 if (gre_handle_offloads(skb, !!(tun_info->key.tun_flags & TUNNEL_CSUM)))
499 goto err_free_skb;
500
501 flags = tun_info->key.tun_flags &
502 (TUNNEL_CSUM | TUNNEL_KEY | TUNNEL_SEQ);
503 gre_build_header(skb, tunnel_hlen, flags, proto,
504 tunnel_id_to_key32(tun_info->key.tun_id),
505 (flags & TUNNEL_SEQ) ? htonl(atomic_fetch_inc(&tunnel->o_seqno)) : 0);
506
507 ip_md_tunnel_xmit(skb, dev, IPPROTO_GRE, tunnel_hlen);
508
509 return;
510
511 err_free_skb:
512 kfree_skb(skb);
513 dev->stats.tx_dropped++;
514 }
515
erspan_fb_xmit(struct sk_buff * skb,struct net_device * dev)516 static void erspan_fb_xmit(struct sk_buff *skb, struct net_device *dev)
517 {
518 struct ip_tunnel *tunnel = netdev_priv(dev);
519 struct ip_tunnel_info *tun_info;
520 const struct ip_tunnel_key *key;
521 struct erspan_metadata *md;
522 bool truncate = false;
523 __be16 proto;
524 int tunnel_hlen;
525 int version;
526 int nhoff;
527
528 tun_info = skb_tunnel_info(skb);
529 if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX) ||
530 ip_tunnel_info_af(tun_info) != AF_INET))
531 goto err_free_skb;
532
533 key = &tun_info->key;
534 if (!(tun_info->key.tun_flags & TUNNEL_ERSPAN_OPT))
535 goto err_free_skb;
536 if (tun_info->options_len < sizeof(*md))
537 goto err_free_skb;
538 md = ip_tunnel_info_opts(tun_info);
539
540 /* ERSPAN has fixed 8 byte GRE header */
541 version = md->version;
542 tunnel_hlen = 8 + erspan_hdr_len(version);
543
544 if (skb_cow_head(skb, dev->needed_headroom))
545 goto err_free_skb;
546
547 if (gre_handle_offloads(skb, false))
548 goto err_free_skb;
549
550 if (skb->len > dev->mtu + dev->hard_header_len) {
551 pskb_trim(skb, dev->mtu + dev->hard_header_len);
552 truncate = true;
553 }
554
555 nhoff = skb_network_offset(skb);
556 if (skb->protocol == htons(ETH_P_IP) &&
557 (ntohs(ip_hdr(skb)->tot_len) > skb->len - nhoff))
558 truncate = true;
559
560 if (skb->protocol == htons(ETH_P_IPV6)) {
561 int thoff;
562
563 if (skb_transport_header_was_set(skb))
564 thoff = skb_transport_offset(skb);
565 else
566 thoff = nhoff + sizeof(struct ipv6hdr);
567 if (ntohs(ipv6_hdr(skb)->payload_len) > skb->len - thoff)
568 truncate = true;
569 }
570
571 if (version == 1) {
572 erspan_build_header(skb, ntohl(tunnel_id_to_key32(key->tun_id)),
573 ntohl(md->u.index), truncate, true);
574 proto = htons(ETH_P_ERSPAN);
575 } else if (version == 2) {
576 erspan_build_header_v2(skb,
577 ntohl(tunnel_id_to_key32(key->tun_id)),
578 md->u.md2.dir,
579 get_hwid(&md->u.md2),
580 truncate, true);
581 proto = htons(ETH_P_ERSPAN2);
582 } else {
583 goto err_free_skb;
584 }
585
586 gre_build_header(skb, 8, TUNNEL_SEQ,
587 proto, 0, htonl(atomic_fetch_inc(&tunnel->o_seqno)));
588
589 ip_md_tunnel_xmit(skb, dev, IPPROTO_GRE, tunnel_hlen);
590
591 return;
592
593 err_free_skb:
594 kfree_skb(skb);
595 dev->stats.tx_dropped++;
596 }
597
gre_fill_metadata_dst(struct net_device * dev,struct sk_buff * skb)598 static int gre_fill_metadata_dst(struct net_device *dev, struct sk_buff *skb)
599 {
600 struct ip_tunnel_info *info = skb_tunnel_info(skb);
601 const struct ip_tunnel_key *key;
602 struct rtable *rt;
603 struct flowi4 fl4;
604
605 if (ip_tunnel_info_af(info) != AF_INET)
606 return -EINVAL;
607
608 key = &info->key;
609 ip_tunnel_init_flow(&fl4, IPPROTO_GRE, key->u.ipv4.dst, key->u.ipv4.src,
610 tunnel_id_to_key32(key->tun_id),
611 key->tos & ~INET_ECN_MASK, 0, skb->mark,
612 skb_get_hash(skb));
613 rt = ip_route_output_key(dev_net(dev), &fl4);
614 if (IS_ERR(rt))
615 return PTR_ERR(rt);
616
617 ip_rt_put(rt);
618 info->key.u.ipv4.src = fl4.saddr;
619 return 0;
620 }
621
ipgre_xmit(struct sk_buff * skb,struct net_device * dev)622 static netdev_tx_t ipgre_xmit(struct sk_buff *skb,
623 struct net_device *dev)
624 {
625 struct ip_tunnel *tunnel = netdev_priv(dev);
626 const struct iphdr *tnl_params;
627
628 if (!pskb_inet_may_pull(skb))
629 goto free_skb;
630
631 if (tunnel->collect_md) {
632 gre_fb_xmit(skb, dev, skb->protocol);
633 return NETDEV_TX_OK;
634 }
635
636 if (dev->header_ops) {
637 int pull_len = tunnel->hlen + sizeof(struct iphdr);
638
639 if (skb_cow_head(skb, 0))
640 goto free_skb;
641
642 tnl_params = (const struct iphdr *)skb->data;
643
644 if (!pskb_network_may_pull(skb, pull_len))
645 goto free_skb;
646
647 /* ip_tunnel_xmit() needs skb->data pointing to gre header. */
648 skb_pull(skb, pull_len);
649 skb_reset_mac_header(skb);
650
651 if (skb->ip_summed == CHECKSUM_PARTIAL &&
652 skb_checksum_start(skb) < skb->data)
653 goto free_skb;
654 } else {
655 if (skb_cow_head(skb, dev->needed_headroom))
656 goto free_skb;
657
658 tnl_params = &tunnel->parms.iph;
659 }
660
661 if (gre_handle_offloads(skb, !!(tunnel->parms.o_flags & TUNNEL_CSUM)))
662 goto free_skb;
663
664 __gre_xmit(skb, dev, tnl_params, skb->protocol);
665 return NETDEV_TX_OK;
666
667 free_skb:
668 kfree_skb(skb);
669 dev->stats.tx_dropped++;
670 return NETDEV_TX_OK;
671 }
672
erspan_xmit(struct sk_buff * skb,struct net_device * dev)673 static netdev_tx_t erspan_xmit(struct sk_buff *skb,
674 struct net_device *dev)
675 {
676 struct ip_tunnel *tunnel = netdev_priv(dev);
677 bool truncate = false;
678 __be16 proto;
679
680 if (!pskb_inet_may_pull(skb))
681 goto free_skb;
682
683 if (tunnel->collect_md) {
684 erspan_fb_xmit(skb, dev);
685 return NETDEV_TX_OK;
686 }
687
688 if (gre_handle_offloads(skb, false))
689 goto free_skb;
690
691 if (skb_cow_head(skb, dev->needed_headroom))
692 goto free_skb;
693
694 if (skb->len > dev->mtu + dev->hard_header_len) {
695 pskb_trim(skb, dev->mtu + dev->hard_header_len);
696 truncate = true;
697 }
698
699 /* Push ERSPAN header */
700 if (tunnel->erspan_ver == 0) {
701 proto = htons(ETH_P_ERSPAN);
702 tunnel->parms.o_flags &= ~TUNNEL_SEQ;
703 } else if (tunnel->erspan_ver == 1) {
704 erspan_build_header(skb, ntohl(tunnel->parms.o_key),
705 tunnel->index,
706 truncate, true);
707 proto = htons(ETH_P_ERSPAN);
708 } else if (tunnel->erspan_ver == 2) {
709 erspan_build_header_v2(skb, ntohl(tunnel->parms.o_key),
710 tunnel->dir, tunnel->hwid,
711 truncate, true);
712 proto = htons(ETH_P_ERSPAN2);
713 } else {
714 goto free_skb;
715 }
716
717 tunnel->parms.o_flags &= ~TUNNEL_KEY;
718 __gre_xmit(skb, dev, &tunnel->parms.iph, proto);
719 return NETDEV_TX_OK;
720
721 free_skb:
722 kfree_skb(skb);
723 dev->stats.tx_dropped++;
724 return NETDEV_TX_OK;
725 }
726
gre_tap_xmit(struct sk_buff * skb,struct net_device * dev)727 static netdev_tx_t gre_tap_xmit(struct sk_buff *skb,
728 struct net_device *dev)
729 {
730 struct ip_tunnel *tunnel = netdev_priv(dev);
731
732 if (!pskb_inet_may_pull(skb))
733 goto free_skb;
734
735 if (tunnel->collect_md) {
736 gre_fb_xmit(skb, dev, htons(ETH_P_TEB));
737 return NETDEV_TX_OK;
738 }
739
740 if (gre_handle_offloads(skb, !!(tunnel->parms.o_flags & TUNNEL_CSUM)))
741 goto free_skb;
742
743 if (skb_cow_head(skb, dev->needed_headroom))
744 goto free_skb;
745
746 __gre_xmit(skb, dev, &tunnel->parms.iph, htons(ETH_P_TEB));
747 return NETDEV_TX_OK;
748
749 free_skb:
750 kfree_skb(skb);
751 dev->stats.tx_dropped++;
752 return NETDEV_TX_OK;
753 }
754
ipgre_link_update(struct net_device * dev,bool set_mtu)755 static void ipgre_link_update(struct net_device *dev, bool set_mtu)
756 {
757 struct ip_tunnel *tunnel = netdev_priv(dev);
758 int len;
759
760 len = tunnel->tun_hlen;
761 tunnel->tun_hlen = gre_calc_hlen(tunnel->parms.o_flags);
762 len = tunnel->tun_hlen - len;
763 tunnel->hlen = tunnel->hlen + len;
764
765 if (dev->header_ops)
766 dev->hard_header_len += len;
767 else
768 dev->needed_headroom += len;
769
770 if (set_mtu)
771 dev->mtu = max_t(int, dev->mtu - len, 68);
772
773 if (!(tunnel->parms.o_flags & TUNNEL_SEQ)) {
774 if (!(tunnel->parms.o_flags & TUNNEL_CSUM) ||
775 tunnel->encap.type == TUNNEL_ENCAP_NONE) {
776 dev->features |= NETIF_F_GSO_SOFTWARE;
777 dev->hw_features |= NETIF_F_GSO_SOFTWARE;
778 } else {
779 dev->features &= ~NETIF_F_GSO_SOFTWARE;
780 dev->hw_features &= ~NETIF_F_GSO_SOFTWARE;
781 }
782 dev->features |= NETIF_F_LLTX;
783 } else {
784 dev->hw_features &= ~NETIF_F_GSO_SOFTWARE;
785 dev->features &= ~(NETIF_F_LLTX | NETIF_F_GSO_SOFTWARE);
786 }
787 }
788
ipgre_tunnel_ctl(struct net_device * dev,struct ip_tunnel_parm * p,int cmd)789 static int ipgre_tunnel_ctl(struct net_device *dev, struct ip_tunnel_parm *p,
790 int cmd)
791 {
792 int err;
793
794 if (cmd == SIOCADDTUNNEL || cmd == SIOCCHGTUNNEL) {
795 if (p->iph.version != 4 || p->iph.protocol != IPPROTO_GRE ||
796 p->iph.ihl != 5 || (p->iph.frag_off & htons(~IP_DF)) ||
797 ((p->i_flags | p->o_flags) & (GRE_VERSION | GRE_ROUTING)))
798 return -EINVAL;
799 }
800
801 p->i_flags = gre_flags_to_tnl_flags(p->i_flags);
802 p->o_flags = gre_flags_to_tnl_flags(p->o_flags);
803
804 err = ip_tunnel_ctl(dev, p, cmd);
805 if (err)
806 return err;
807
808 if (cmd == SIOCCHGTUNNEL) {
809 struct ip_tunnel *t = netdev_priv(dev);
810
811 t->parms.i_flags = p->i_flags;
812 t->parms.o_flags = p->o_flags;
813
814 if (strcmp(dev->rtnl_link_ops->kind, "erspan"))
815 ipgre_link_update(dev, true);
816 }
817
818 p->i_flags = gre_tnl_flags_to_gre_flags(p->i_flags);
819 p->o_flags = gre_tnl_flags_to_gre_flags(p->o_flags);
820 return 0;
821 }
822
823 /* Nice toy. Unfortunately, useless in real life :-)
824 It allows to construct virtual multiprotocol broadcast "LAN"
825 over the Internet, provided multicast routing is tuned.
826
827
828 I have no idea was this bicycle invented before me,
829 so that I had to set ARPHRD_IPGRE to a random value.
830 I have an impression, that Cisco could make something similar,
831 but this feature is apparently missing in IOS<=11.2(8).
832
833 I set up 10.66.66/24 and fec0:6666:6666::0/96 as virtual networks
834 with broadcast 224.66.66.66. If you have access to mbone, play with me :-)
835
836 ping -t 255 224.66.66.66
837
838 If nobody answers, mbone does not work.
839
840 ip tunnel add Universe mode gre remote 224.66.66.66 local <Your_real_addr> ttl 255
841 ip addr add 10.66.66.<somewhat>/24 dev Universe
842 ifconfig Universe up
843 ifconfig Universe add fe80::<Your_real_addr>/10
844 ifconfig Universe add fec0:6666:6666::<Your_real_addr>/96
845 ftp 10.66.66.66
846 ...
847 ftp fec0:6666:6666::193.233.7.65
848 ...
849 */
ipgre_header(struct sk_buff * skb,struct net_device * dev,unsigned short type,const void * daddr,const void * saddr,unsigned int len)850 static int ipgre_header(struct sk_buff *skb, struct net_device *dev,
851 unsigned short type,
852 const void *daddr, const void *saddr, unsigned int len)
853 {
854 struct ip_tunnel *t = netdev_priv(dev);
855 struct iphdr *iph;
856 struct gre_base_hdr *greh;
857
858 iph = skb_push(skb, t->hlen + sizeof(*iph));
859 greh = (struct gre_base_hdr *)(iph+1);
860 greh->flags = gre_tnl_flags_to_gre_flags(t->parms.o_flags);
861 greh->protocol = htons(type);
862
863 memcpy(iph, &t->parms.iph, sizeof(struct iphdr));
864
865 /* Set the source hardware address. */
866 if (saddr)
867 memcpy(&iph->saddr, saddr, 4);
868 if (daddr)
869 memcpy(&iph->daddr, daddr, 4);
870 if (iph->daddr)
871 return t->hlen + sizeof(*iph);
872
873 return -(t->hlen + sizeof(*iph));
874 }
875
ipgre_header_parse(const struct sk_buff * skb,unsigned char * haddr)876 static int ipgre_header_parse(const struct sk_buff *skb, unsigned char *haddr)
877 {
878 const struct iphdr *iph = (const struct iphdr *) skb_mac_header(skb);
879 memcpy(haddr, &iph->saddr, 4);
880 return 4;
881 }
882
883 static const struct header_ops ipgre_header_ops = {
884 .create = ipgre_header,
885 .parse = ipgre_header_parse,
886 };
887
888 #ifdef CONFIG_NET_IPGRE_BROADCAST
ipgre_open(struct net_device * dev)889 static int ipgre_open(struct net_device *dev)
890 {
891 struct ip_tunnel *t = netdev_priv(dev);
892
893 if (ipv4_is_multicast(t->parms.iph.daddr)) {
894 struct flowi4 fl4;
895 struct rtable *rt;
896
897 rt = ip_route_output_gre(t->net, &fl4,
898 t->parms.iph.daddr,
899 t->parms.iph.saddr,
900 t->parms.o_key,
901 RT_TOS(t->parms.iph.tos),
902 t->parms.link);
903 if (IS_ERR(rt))
904 return -EADDRNOTAVAIL;
905 dev = rt->dst.dev;
906 ip_rt_put(rt);
907 if (!__in_dev_get_rtnl(dev))
908 return -EADDRNOTAVAIL;
909 t->mlink = dev->ifindex;
910 ip_mc_inc_group(__in_dev_get_rtnl(dev), t->parms.iph.daddr);
911 }
912 return 0;
913 }
914
ipgre_close(struct net_device * dev)915 static int ipgre_close(struct net_device *dev)
916 {
917 struct ip_tunnel *t = netdev_priv(dev);
918
919 if (ipv4_is_multicast(t->parms.iph.daddr) && t->mlink) {
920 struct in_device *in_dev;
921 in_dev = inetdev_by_index(t->net, t->mlink);
922 if (in_dev)
923 ip_mc_dec_group(in_dev, t->parms.iph.daddr);
924 }
925 return 0;
926 }
927 #endif
928
929 static const struct net_device_ops ipgre_netdev_ops = {
930 .ndo_init = ipgre_tunnel_init,
931 .ndo_uninit = ip_tunnel_uninit,
932 #ifdef CONFIG_NET_IPGRE_BROADCAST
933 .ndo_open = ipgre_open,
934 .ndo_stop = ipgre_close,
935 #endif
936 .ndo_start_xmit = ipgre_xmit,
937 .ndo_siocdevprivate = ip_tunnel_siocdevprivate,
938 .ndo_change_mtu = ip_tunnel_change_mtu,
939 .ndo_get_stats64 = dev_get_tstats64,
940 .ndo_get_iflink = ip_tunnel_get_iflink,
941 .ndo_tunnel_ctl = ipgre_tunnel_ctl,
942 };
943
944 #define GRE_FEATURES (NETIF_F_SG | \
945 NETIF_F_FRAGLIST | \
946 NETIF_F_HIGHDMA | \
947 NETIF_F_HW_CSUM)
948
ipgre_tunnel_setup(struct net_device * dev)949 static void ipgre_tunnel_setup(struct net_device *dev)
950 {
951 dev->netdev_ops = &ipgre_netdev_ops;
952 dev->type = ARPHRD_IPGRE;
953 ip_tunnel_setup(dev, ipgre_net_id);
954 }
955
__gre_tunnel_init(struct net_device * dev)956 static void __gre_tunnel_init(struct net_device *dev)
957 {
958 struct ip_tunnel *tunnel;
959
960 tunnel = netdev_priv(dev);
961 tunnel->tun_hlen = gre_calc_hlen(tunnel->parms.o_flags);
962 tunnel->parms.iph.protocol = IPPROTO_GRE;
963
964 tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen;
965 dev->needed_headroom = tunnel->hlen + sizeof(tunnel->parms.iph);
966
967 dev->features |= GRE_FEATURES;
968 dev->hw_features |= GRE_FEATURES;
969
970 if (!(tunnel->parms.o_flags & TUNNEL_SEQ)) {
971 /* TCP offload with GRE SEQ is not supported, nor
972 * can we support 2 levels of outer headers requiring
973 * an update.
974 */
975 if (!(tunnel->parms.o_flags & TUNNEL_CSUM) ||
976 (tunnel->encap.type == TUNNEL_ENCAP_NONE)) {
977 dev->features |= NETIF_F_GSO_SOFTWARE;
978 dev->hw_features |= NETIF_F_GSO_SOFTWARE;
979 }
980
981 /* Can use a lockless transmit, unless we generate
982 * output sequences
983 */
984 dev->features |= NETIF_F_LLTX;
985 }
986 }
987
ipgre_tunnel_init(struct net_device * dev)988 static int ipgre_tunnel_init(struct net_device *dev)
989 {
990 struct ip_tunnel *tunnel = netdev_priv(dev);
991 struct iphdr *iph = &tunnel->parms.iph;
992
993 __gre_tunnel_init(dev);
994
995 memcpy(dev->dev_addr, &iph->saddr, 4);
996 memcpy(dev->broadcast, &iph->daddr, 4);
997
998 dev->flags = IFF_NOARP;
999 netif_keep_dst(dev);
1000 dev->addr_len = 4;
1001
1002 if (iph->daddr && !tunnel->collect_md) {
1003 #ifdef CONFIG_NET_IPGRE_BROADCAST
1004 if (ipv4_is_multicast(iph->daddr)) {
1005 if (!iph->saddr)
1006 return -EINVAL;
1007 dev->flags = IFF_BROADCAST;
1008 dev->header_ops = &ipgre_header_ops;
1009 dev->hard_header_len = tunnel->hlen + sizeof(*iph);
1010 dev->needed_headroom = 0;
1011 }
1012 #endif
1013 } else if (!tunnel->collect_md) {
1014 dev->header_ops = &ipgre_header_ops;
1015 dev->hard_header_len = tunnel->hlen + sizeof(*iph);
1016 dev->needed_headroom = 0;
1017 }
1018
1019 return ip_tunnel_init(dev);
1020 }
1021
1022 static const struct gre_protocol ipgre_protocol = {
1023 .handler = gre_rcv,
1024 .err_handler = gre_err,
1025 };
1026
ipgre_init_net(struct net * net)1027 static int __net_init ipgre_init_net(struct net *net)
1028 {
1029 return ip_tunnel_init_net(net, ipgre_net_id, &ipgre_link_ops, NULL);
1030 }
1031
ipgre_exit_batch_net(struct list_head * list_net)1032 static void __net_exit ipgre_exit_batch_net(struct list_head *list_net)
1033 {
1034 ip_tunnel_delete_nets(list_net, ipgre_net_id, &ipgre_link_ops);
1035 }
1036
1037 static struct pernet_operations ipgre_net_ops = {
1038 .init = ipgre_init_net,
1039 .exit_batch = ipgre_exit_batch_net,
1040 .id = &ipgre_net_id,
1041 .size = sizeof(struct ip_tunnel_net),
1042 };
1043
ipgre_tunnel_validate(struct nlattr * tb[],struct nlattr * data[],struct netlink_ext_ack * extack)1044 static int ipgre_tunnel_validate(struct nlattr *tb[], struct nlattr *data[],
1045 struct netlink_ext_ack *extack)
1046 {
1047 __be16 flags;
1048
1049 if (!data)
1050 return 0;
1051
1052 flags = 0;
1053 if (data[IFLA_GRE_IFLAGS])
1054 flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]);
1055 if (data[IFLA_GRE_OFLAGS])
1056 flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]);
1057 if (flags & (GRE_VERSION|GRE_ROUTING))
1058 return -EINVAL;
1059
1060 if (data[IFLA_GRE_COLLECT_METADATA] &&
1061 data[IFLA_GRE_ENCAP_TYPE] &&
1062 nla_get_u16(data[IFLA_GRE_ENCAP_TYPE]) != TUNNEL_ENCAP_NONE)
1063 return -EINVAL;
1064
1065 return 0;
1066 }
1067
ipgre_tap_validate(struct nlattr * tb[],struct nlattr * data[],struct netlink_ext_ack * extack)1068 static int ipgre_tap_validate(struct nlattr *tb[], struct nlattr *data[],
1069 struct netlink_ext_ack *extack)
1070 {
1071 __be32 daddr;
1072
1073 if (tb[IFLA_ADDRESS]) {
1074 if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
1075 return -EINVAL;
1076 if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
1077 return -EADDRNOTAVAIL;
1078 }
1079
1080 if (!data)
1081 goto out;
1082
1083 if (data[IFLA_GRE_REMOTE]) {
1084 memcpy(&daddr, nla_data(data[IFLA_GRE_REMOTE]), 4);
1085 if (!daddr)
1086 return -EINVAL;
1087 }
1088
1089 out:
1090 return ipgre_tunnel_validate(tb, data, extack);
1091 }
1092
erspan_validate(struct nlattr * tb[],struct nlattr * data[],struct netlink_ext_ack * extack)1093 static int erspan_validate(struct nlattr *tb[], struct nlattr *data[],
1094 struct netlink_ext_ack *extack)
1095 {
1096 __be16 flags = 0;
1097 int ret;
1098
1099 if (!data)
1100 return 0;
1101
1102 ret = ipgre_tap_validate(tb, data, extack);
1103 if (ret)
1104 return ret;
1105
1106 if (data[IFLA_GRE_ERSPAN_VER] &&
1107 nla_get_u8(data[IFLA_GRE_ERSPAN_VER]) == 0)
1108 return 0;
1109
1110 /* ERSPAN type II/III should only have GRE sequence and key flag */
1111 if (data[IFLA_GRE_OFLAGS])
1112 flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]);
1113 if (data[IFLA_GRE_IFLAGS])
1114 flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]);
1115 if (!data[IFLA_GRE_COLLECT_METADATA] &&
1116 flags != (GRE_SEQ | GRE_KEY))
1117 return -EINVAL;
1118
1119 /* ERSPAN Session ID only has 10-bit. Since we reuse
1120 * 32-bit key field as ID, check it's range.
1121 */
1122 if (data[IFLA_GRE_IKEY] &&
1123 (ntohl(nla_get_be32(data[IFLA_GRE_IKEY])) & ~ID_MASK))
1124 return -EINVAL;
1125
1126 if (data[IFLA_GRE_OKEY] &&
1127 (ntohl(nla_get_be32(data[IFLA_GRE_OKEY])) & ~ID_MASK))
1128 return -EINVAL;
1129
1130 return 0;
1131 }
1132
ipgre_netlink_parms(struct net_device * dev,struct nlattr * data[],struct nlattr * tb[],struct ip_tunnel_parm * parms,__u32 * fwmark)1133 static int ipgre_netlink_parms(struct net_device *dev,
1134 struct nlattr *data[],
1135 struct nlattr *tb[],
1136 struct ip_tunnel_parm *parms,
1137 __u32 *fwmark)
1138 {
1139 struct ip_tunnel *t = netdev_priv(dev);
1140
1141 memset(parms, 0, sizeof(*parms));
1142
1143 parms->iph.protocol = IPPROTO_GRE;
1144
1145 if (!data)
1146 return 0;
1147
1148 if (data[IFLA_GRE_LINK])
1149 parms->link = nla_get_u32(data[IFLA_GRE_LINK]);
1150
1151 if (data[IFLA_GRE_IFLAGS])
1152 parms->i_flags = gre_flags_to_tnl_flags(nla_get_be16(data[IFLA_GRE_IFLAGS]));
1153
1154 if (data[IFLA_GRE_OFLAGS])
1155 parms->o_flags = gre_flags_to_tnl_flags(nla_get_be16(data[IFLA_GRE_OFLAGS]));
1156
1157 if (data[IFLA_GRE_IKEY])
1158 parms->i_key = nla_get_be32(data[IFLA_GRE_IKEY]);
1159
1160 if (data[IFLA_GRE_OKEY])
1161 parms->o_key = nla_get_be32(data[IFLA_GRE_OKEY]);
1162
1163 if (data[IFLA_GRE_LOCAL])
1164 parms->iph.saddr = nla_get_in_addr(data[IFLA_GRE_LOCAL]);
1165
1166 if (data[IFLA_GRE_REMOTE])
1167 parms->iph.daddr = nla_get_in_addr(data[IFLA_GRE_REMOTE]);
1168
1169 if (data[IFLA_GRE_TTL])
1170 parms->iph.ttl = nla_get_u8(data[IFLA_GRE_TTL]);
1171
1172 if (data[IFLA_GRE_TOS])
1173 parms->iph.tos = nla_get_u8(data[IFLA_GRE_TOS]);
1174
1175 if (!data[IFLA_GRE_PMTUDISC] || nla_get_u8(data[IFLA_GRE_PMTUDISC])) {
1176 if (t->ignore_df)
1177 return -EINVAL;
1178 parms->iph.frag_off = htons(IP_DF);
1179 }
1180
1181 if (data[IFLA_GRE_COLLECT_METADATA]) {
1182 t->collect_md = true;
1183 if (dev->type == ARPHRD_IPGRE)
1184 dev->type = ARPHRD_NONE;
1185 }
1186
1187 if (data[IFLA_GRE_IGNORE_DF]) {
1188 if (nla_get_u8(data[IFLA_GRE_IGNORE_DF])
1189 && (parms->iph.frag_off & htons(IP_DF)))
1190 return -EINVAL;
1191 t->ignore_df = !!nla_get_u8(data[IFLA_GRE_IGNORE_DF]);
1192 }
1193
1194 if (data[IFLA_GRE_FWMARK])
1195 *fwmark = nla_get_u32(data[IFLA_GRE_FWMARK]);
1196
1197 return 0;
1198 }
1199
erspan_netlink_parms(struct net_device * dev,struct nlattr * data[],struct nlattr * tb[],struct ip_tunnel_parm * parms,__u32 * fwmark)1200 static int erspan_netlink_parms(struct net_device *dev,
1201 struct nlattr *data[],
1202 struct nlattr *tb[],
1203 struct ip_tunnel_parm *parms,
1204 __u32 *fwmark)
1205 {
1206 struct ip_tunnel *t = netdev_priv(dev);
1207 int err;
1208
1209 err = ipgre_netlink_parms(dev, data, tb, parms, fwmark);
1210 if (err)
1211 return err;
1212 if (!data)
1213 return 0;
1214
1215 if (data[IFLA_GRE_ERSPAN_VER]) {
1216 t->erspan_ver = nla_get_u8(data[IFLA_GRE_ERSPAN_VER]);
1217
1218 if (t->erspan_ver > 2)
1219 return -EINVAL;
1220 }
1221
1222 if (t->erspan_ver == 1) {
1223 if (data[IFLA_GRE_ERSPAN_INDEX]) {
1224 t->index = nla_get_u32(data[IFLA_GRE_ERSPAN_INDEX]);
1225 if (t->index & ~INDEX_MASK)
1226 return -EINVAL;
1227 }
1228 } else if (t->erspan_ver == 2) {
1229 if (data[IFLA_GRE_ERSPAN_DIR]) {
1230 t->dir = nla_get_u8(data[IFLA_GRE_ERSPAN_DIR]);
1231 if (t->dir & ~(DIR_MASK >> DIR_OFFSET))
1232 return -EINVAL;
1233 }
1234 if (data[IFLA_GRE_ERSPAN_HWID]) {
1235 t->hwid = nla_get_u16(data[IFLA_GRE_ERSPAN_HWID]);
1236 if (t->hwid & ~(HWID_MASK >> HWID_OFFSET))
1237 return -EINVAL;
1238 }
1239 }
1240
1241 return 0;
1242 }
1243
1244 /* This function returns true when ENCAP attributes are present in the nl msg */
ipgre_netlink_encap_parms(struct nlattr * data[],struct ip_tunnel_encap * ipencap)1245 static bool ipgre_netlink_encap_parms(struct nlattr *data[],
1246 struct ip_tunnel_encap *ipencap)
1247 {
1248 bool ret = false;
1249
1250 memset(ipencap, 0, sizeof(*ipencap));
1251
1252 if (!data)
1253 return ret;
1254
1255 if (data[IFLA_GRE_ENCAP_TYPE]) {
1256 ret = true;
1257 ipencap->type = nla_get_u16(data[IFLA_GRE_ENCAP_TYPE]);
1258 }
1259
1260 if (data[IFLA_GRE_ENCAP_FLAGS]) {
1261 ret = true;
1262 ipencap->flags = nla_get_u16(data[IFLA_GRE_ENCAP_FLAGS]);
1263 }
1264
1265 if (data[IFLA_GRE_ENCAP_SPORT]) {
1266 ret = true;
1267 ipencap->sport = nla_get_be16(data[IFLA_GRE_ENCAP_SPORT]);
1268 }
1269
1270 if (data[IFLA_GRE_ENCAP_DPORT]) {
1271 ret = true;
1272 ipencap->dport = nla_get_be16(data[IFLA_GRE_ENCAP_DPORT]);
1273 }
1274
1275 return ret;
1276 }
1277
gre_tap_init(struct net_device * dev)1278 static int gre_tap_init(struct net_device *dev)
1279 {
1280 __gre_tunnel_init(dev);
1281 dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1282 netif_keep_dst(dev);
1283
1284 return ip_tunnel_init(dev);
1285 }
1286
1287 static const struct net_device_ops gre_tap_netdev_ops = {
1288 .ndo_init = gre_tap_init,
1289 .ndo_uninit = ip_tunnel_uninit,
1290 .ndo_start_xmit = gre_tap_xmit,
1291 .ndo_set_mac_address = eth_mac_addr,
1292 .ndo_validate_addr = eth_validate_addr,
1293 .ndo_change_mtu = ip_tunnel_change_mtu,
1294 .ndo_get_stats64 = dev_get_tstats64,
1295 .ndo_get_iflink = ip_tunnel_get_iflink,
1296 .ndo_fill_metadata_dst = gre_fill_metadata_dst,
1297 };
1298
erspan_tunnel_init(struct net_device * dev)1299 static int erspan_tunnel_init(struct net_device *dev)
1300 {
1301 struct ip_tunnel *tunnel = netdev_priv(dev);
1302
1303 if (tunnel->erspan_ver == 0)
1304 tunnel->tun_hlen = 4; /* 4-byte GRE hdr. */
1305 else
1306 tunnel->tun_hlen = 8; /* 8-byte GRE hdr. */
1307
1308 tunnel->parms.iph.protocol = IPPROTO_GRE;
1309 tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen +
1310 erspan_hdr_len(tunnel->erspan_ver);
1311
1312 dev->features |= GRE_FEATURES;
1313 dev->hw_features |= GRE_FEATURES;
1314 dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1315 netif_keep_dst(dev);
1316
1317 return ip_tunnel_init(dev);
1318 }
1319
1320 static const struct net_device_ops erspan_netdev_ops = {
1321 .ndo_init = erspan_tunnel_init,
1322 .ndo_uninit = ip_tunnel_uninit,
1323 .ndo_start_xmit = erspan_xmit,
1324 .ndo_set_mac_address = eth_mac_addr,
1325 .ndo_validate_addr = eth_validate_addr,
1326 .ndo_change_mtu = ip_tunnel_change_mtu,
1327 .ndo_get_stats64 = dev_get_tstats64,
1328 .ndo_get_iflink = ip_tunnel_get_iflink,
1329 .ndo_fill_metadata_dst = gre_fill_metadata_dst,
1330 };
1331
ipgre_tap_setup(struct net_device * dev)1332 static void ipgre_tap_setup(struct net_device *dev)
1333 {
1334 ether_setup(dev);
1335 dev->max_mtu = 0;
1336 dev->netdev_ops = &gre_tap_netdev_ops;
1337 dev->priv_flags &= ~IFF_TX_SKB_SHARING;
1338 dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1339 ip_tunnel_setup(dev, gre_tap_net_id);
1340 }
1341
1342 static int
ipgre_newlink_encap_setup(struct net_device * dev,struct nlattr * data[])1343 ipgre_newlink_encap_setup(struct net_device *dev, struct nlattr *data[])
1344 {
1345 struct ip_tunnel_encap ipencap;
1346
1347 if (ipgre_netlink_encap_parms(data, &ipencap)) {
1348 struct ip_tunnel *t = netdev_priv(dev);
1349 int err = ip_tunnel_encap_setup(t, &ipencap);
1350
1351 if (err < 0)
1352 return err;
1353 }
1354
1355 return 0;
1356 }
1357
ipgre_newlink(struct net * src_net,struct net_device * dev,struct nlattr * tb[],struct nlattr * data[],struct netlink_ext_ack * extack)1358 static int ipgre_newlink(struct net *src_net, struct net_device *dev,
1359 struct nlattr *tb[], struct nlattr *data[],
1360 struct netlink_ext_ack *extack)
1361 {
1362 struct ip_tunnel_parm p;
1363 __u32 fwmark = 0;
1364 int err;
1365
1366 err = ipgre_newlink_encap_setup(dev, data);
1367 if (err)
1368 return err;
1369
1370 err = ipgre_netlink_parms(dev, data, tb, &p, &fwmark);
1371 if (err < 0)
1372 return err;
1373 return ip_tunnel_newlink(dev, tb, &p, fwmark);
1374 }
1375
erspan_newlink(struct net * src_net,struct net_device * dev,struct nlattr * tb[],struct nlattr * data[],struct netlink_ext_ack * extack)1376 static int erspan_newlink(struct net *src_net, struct net_device *dev,
1377 struct nlattr *tb[], struct nlattr *data[],
1378 struct netlink_ext_ack *extack)
1379 {
1380 struct ip_tunnel_parm p;
1381 __u32 fwmark = 0;
1382 int err;
1383
1384 err = ipgre_newlink_encap_setup(dev, data);
1385 if (err)
1386 return err;
1387
1388 err = erspan_netlink_parms(dev, data, tb, &p, &fwmark);
1389 if (err)
1390 return err;
1391 return ip_tunnel_newlink(dev, tb, &p, fwmark);
1392 }
1393
ipgre_changelink(struct net_device * dev,struct nlattr * tb[],struct nlattr * data[],struct netlink_ext_ack * extack)1394 static int ipgre_changelink(struct net_device *dev, struct nlattr *tb[],
1395 struct nlattr *data[],
1396 struct netlink_ext_ack *extack)
1397 {
1398 struct ip_tunnel *t = netdev_priv(dev);
1399 __u32 fwmark = t->fwmark;
1400 struct ip_tunnel_parm p;
1401 int err;
1402
1403 err = ipgre_newlink_encap_setup(dev, data);
1404 if (err)
1405 return err;
1406
1407 err = ipgre_netlink_parms(dev, data, tb, &p, &fwmark);
1408 if (err < 0)
1409 return err;
1410
1411 err = ip_tunnel_changelink(dev, tb, &p, fwmark);
1412 if (err < 0)
1413 return err;
1414
1415 t->parms.i_flags = p.i_flags;
1416 t->parms.o_flags = p.o_flags;
1417
1418 ipgre_link_update(dev, !tb[IFLA_MTU]);
1419
1420 return 0;
1421 }
1422
erspan_changelink(struct net_device * dev,struct nlattr * tb[],struct nlattr * data[],struct netlink_ext_ack * extack)1423 static int erspan_changelink(struct net_device *dev, struct nlattr *tb[],
1424 struct nlattr *data[],
1425 struct netlink_ext_ack *extack)
1426 {
1427 struct ip_tunnel *t = netdev_priv(dev);
1428 __u32 fwmark = t->fwmark;
1429 struct ip_tunnel_parm p;
1430 int err;
1431
1432 err = ipgre_newlink_encap_setup(dev, data);
1433 if (err)
1434 return err;
1435
1436 err = erspan_netlink_parms(dev, data, tb, &p, &fwmark);
1437 if (err < 0)
1438 return err;
1439
1440 err = ip_tunnel_changelink(dev, tb, &p, fwmark);
1441 if (err < 0)
1442 return err;
1443
1444 t->parms.i_flags = p.i_flags;
1445 t->parms.o_flags = p.o_flags;
1446
1447 return 0;
1448 }
1449
ipgre_get_size(const struct net_device * dev)1450 static size_t ipgre_get_size(const struct net_device *dev)
1451 {
1452 return
1453 /* IFLA_GRE_LINK */
1454 nla_total_size(4) +
1455 /* IFLA_GRE_IFLAGS */
1456 nla_total_size(2) +
1457 /* IFLA_GRE_OFLAGS */
1458 nla_total_size(2) +
1459 /* IFLA_GRE_IKEY */
1460 nla_total_size(4) +
1461 /* IFLA_GRE_OKEY */
1462 nla_total_size(4) +
1463 /* IFLA_GRE_LOCAL */
1464 nla_total_size(4) +
1465 /* IFLA_GRE_REMOTE */
1466 nla_total_size(4) +
1467 /* IFLA_GRE_TTL */
1468 nla_total_size(1) +
1469 /* IFLA_GRE_TOS */
1470 nla_total_size(1) +
1471 /* IFLA_GRE_PMTUDISC */
1472 nla_total_size(1) +
1473 /* IFLA_GRE_ENCAP_TYPE */
1474 nla_total_size(2) +
1475 /* IFLA_GRE_ENCAP_FLAGS */
1476 nla_total_size(2) +
1477 /* IFLA_GRE_ENCAP_SPORT */
1478 nla_total_size(2) +
1479 /* IFLA_GRE_ENCAP_DPORT */
1480 nla_total_size(2) +
1481 /* IFLA_GRE_COLLECT_METADATA */
1482 nla_total_size(0) +
1483 /* IFLA_GRE_IGNORE_DF */
1484 nla_total_size(1) +
1485 /* IFLA_GRE_FWMARK */
1486 nla_total_size(4) +
1487 /* IFLA_GRE_ERSPAN_INDEX */
1488 nla_total_size(4) +
1489 /* IFLA_GRE_ERSPAN_VER */
1490 nla_total_size(1) +
1491 /* IFLA_GRE_ERSPAN_DIR */
1492 nla_total_size(1) +
1493 /* IFLA_GRE_ERSPAN_HWID */
1494 nla_total_size(2) +
1495 0;
1496 }
1497
ipgre_fill_info(struct sk_buff * skb,const struct net_device * dev)1498 static int ipgre_fill_info(struct sk_buff *skb, const struct net_device *dev)
1499 {
1500 struct ip_tunnel *t = netdev_priv(dev);
1501 struct ip_tunnel_parm *p = &t->parms;
1502 __be16 o_flags = p->o_flags;
1503
1504 if (nla_put_u32(skb, IFLA_GRE_LINK, p->link) ||
1505 nla_put_be16(skb, IFLA_GRE_IFLAGS,
1506 gre_tnl_flags_to_gre_flags(p->i_flags)) ||
1507 nla_put_be16(skb, IFLA_GRE_OFLAGS,
1508 gre_tnl_flags_to_gre_flags(o_flags)) ||
1509 nla_put_be32(skb, IFLA_GRE_IKEY, p->i_key) ||
1510 nla_put_be32(skb, IFLA_GRE_OKEY, p->o_key) ||
1511 nla_put_in_addr(skb, IFLA_GRE_LOCAL, p->iph.saddr) ||
1512 nla_put_in_addr(skb, IFLA_GRE_REMOTE, p->iph.daddr) ||
1513 nla_put_u8(skb, IFLA_GRE_TTL, p->iph.ttl) ||
1514 nla_put_u8(skb, IFLA_GRE_TOS, p->iph.tos) ||
1515 nla_put_u8(skb, IFLA_GRE_PMTUDISC,
1516 !!(p->iph.frag_off & htons(IP_DF))) ||
1517 nla_put_u32(skb, IFLA_GRE_FWMARK, t->fwmark))
1518 goto nla_put_failure;
1519
1520 if (nla_put_u16(skb, IFLA_GRE_ENCAP_TYPE,
1521 t->encap.type) ||
1522 nla_put_be16(skb, IFLA_GRE_ENCAP_SPORT,
1523 t->encap.sport) ||
1524 nla_put_be16(skb, IFLA_GRE_ENCAP_DPORT,
1525 t->encap.dport) ||
1526 nla_put_u16(skb, IFLA_GRE_ENCAP_FLAGS,
1527 t->encap.flags))
1528 goto nla_put_failure;
1529
1530 if (nla_put_u8(skb, IFLA_GRE_IGNORE_DF, t->ignore_df))
1531 goto nla_put_failure;
1532
1533 if (t->collect_md) {
1534 if (nla_put_flag(skb, IFLA_GRE_COLLECT_METADATA))
1535 goto nla_put_failure;
1536 }
1537
1538 return 0;
1539
1540 nla_put_failure:
1541 return -EMSGSIZE;
1542 }
1543
erspan_fill_info(struct sk_buff * skb,const struct net_device * dev)1544 static int erspan_fill_info(struct sk_buff *skb, const struct net_device *dev)
1545 {
1546 struct ip_tunnel *t = netdev_priv(dev);
1547
1548 if (t->erspan_ver <= 2) {
1549 if (t->erspan_ver != 0 && !t->collect_md)
1550 t->parms.o_flags |= TUNNEL_KEY;
1551
1552 if (nla_put_u8(skb, IFLA_GRE_ERSPAN_VER, t->erspan_ver))
1553 goto nla_put_failure;
1554
1555 if (t->erspan_ver == 1) {
1556 if (nla_put_u32(skb, IFLA_GRE_ERSPAN_INDEX, t->index))
1557 goto nla_put_failure;
1558 } else if (t->erspan_ver == 2) {
1559 if (nla_put_u8(skb, IFLA_GRE_ERSPAN_DIR, t->dir))
1560 goto nla_put_failure;
1561 if (nla_put_u16(skb, IFLA_GRE_ERSPAN_HWID, t->hwid))
1562 goto nla_put_failure;
1563 }
1564 }
1565
1566 return ipgre_fill_info(skb, dev);
1567
1568 nla_put_failure:
1569 return -EMSGSIZE;
1570 }
1571
erspan_setup(struct net_device * dev)1572 static void erspan_setup(struct net_device *dev)
1573 {
1574 struct ip_tunnel *t = netdev_priv(dev);
1575
1576 ether_setup(dev);
1577 dev->max_mtu = 0;
1578 dev->netdev_ops = &erspan_netdev_ops;
1579 dev->priv_flags &= ~IFF_TX_SKB_SHARING;
1580 dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1581 ip_tunnel_setup(dev, erspan_net_id);
1582 t->erspan_ver = 1;
1583 }
1584
1585 static const struct nla_policy ipgre_policy[IFLA_GRE_MAX + 1] = {
1586 [IFLA_GRE_LINK] = { .type = NLA_U32 },
1587 [IFLA_GRE_IFLAGS] = { .type = NLA_U16 },
1588 [IFLA_GRE_OFLAGS] = { .type = NLA_U16 },
1589 [IFLA_GRE_IKEY] = { .type = NLA_U32 },
1590 [IFLA_GRE_OKEY] = { .type = NLA_U32 },
1591 [IFLA_GRE_LOCAL] = { .len = sizeof_field(struct iphdr, saddr) },
1592 [IFLA_GRE_REMOTE] = { .len = sizeof_field(struct iphdr, daddr) },
1593 [IFLA_GRE_TTL] = { .type = NLA_U8 },
1594 [IFLA_GRE_TOS] = { .type = NLA_U8 },
1595 [IFLA_GRE_PMTUDISC] = { .type = NLA_U8 },
1596 [IFLA_GRE_ENCAP_TYPE] = { .type = NLA_U16 },
1597 [IFLA_GRE_ENCAP_FLAGS] = { .type = NLA_U16 },
1598 [IFLA_GRE_ENCAP_SPORT] = { .type = NLA_U16 },
1599 [IFLA_GRE_ENCAP_DPORT] = { .type = NLA_U16 },
1600 [IFLA_GRE_COLLECT_METADATA] = { .type = NLA_FLAG },
1601 [IFLA_GRE_IGNORE_DF] = { .type = NLA_U8 },
1602 [IFLA_GRE_FWMARK] = { .type = NLA_U32 },
1603 [IFLA_GRE_ERSPAN_INDEX] = { .type = NLA_U32 },
1604 [IFLA_GRE_ERSPAN_VER] = { .type = NLA_U8 },
1605 [IFLA_GRE_ERSPAN_DIR] = { .type = NLA_U8 },
1606 [IFLA_GRE_ERSPAN_HWID] = { .type = NLA_U16 },
1607 };
1608
1609 static struct rtnl_link_ops ipgre_link_ops __read_mostly = {
1610 .kind = "gre",
1611 .maxtype = IFLA_GRE_MAX,
1612 .policy = ipgre_policy,
1613 .priv_size = sizeof(struct ip_tunnel),
1614 .setup = ipgre_tunnel_setup,
1615 .validate = ipgre_tunnel_validate,
1616 .newlink = ipgre_newlink,
1617 .changelink = ipgre_changelink,
1618 .dellink = ip_tunnel_dellink,
1619 .get_size = ipgre_get_size,
1620 .fill_info = ipgre_fill_info,
1621 .get_link_net = ip_tunnel_get_link_net,
1622 };
1623
1624 static struct rtnl_link_ops ipgre_tap_ops __read_mostly = {
1625 .kind = "gretap",
1626 .maxtype = IFLA_GRE_MAX,
1627 .policy = ipgre_policy,
1628 .priv_size = sizeof(struct ip_tunnel),
1629 .setup = ipgre_tap_setup,
1630 .validate = ipgre_tap_validate,
1631 .newlink = ipgre_newlink,
1632 .changelink = ipgre_changelink,
1633 .dellink = ip_tunnel_dellink,
1634 .get_size = ipgre_get_size,
1635 .fill_info = ipgre_fill_info,
1636 .get_link_net = ip_tunnel_get_link_net,
1637 };
1638
1639 static struct rtnl_link_ops erspan_link_ops __read_mostly = {
1640 .kind = "erspan",
1641 .maxtype = IFLA_GRE_MAX,
1642 .policy = ipgre_policy,
1643 .priv_size = sizeof(struct ip_tunnel),
1644 .setup = erspan_setup,
1645 .validate = erspan_validate,
1646 .newlink = erspan_newlink,
1647 .changelink = erspan_changelink,
1648 .dellink = ip_tunnel_dellink,
1649 .get_size = ipgre_get_size,
1650 .fill_info = erspan_fill_info,
1651 .get_link_net = ip_tunnel_get_link_net,
1652 };
1653
gretap_fb_dev_create(struct net * net,const char * name,u8 name_assign_type)1654 struct net_device *gretap_fb_dev_create(struct net *net, const char *name,
1655 u8 name_assign_type)
1656 {
1657 struct nlattr *tb[IFLA_MAX + 1];
1658 struct net_device *dev;
1659 LIST_HEAD(list_kill);
1660 struct ip_tunnel *t;
1661 int err;
1662
1663 memset(&tb, 0, sizeof(tb));
1664
1665 dev = rtnl_create_link(net, name, name_assign_type,
1666 &ipgre_tap_ops, tb, NULL);
1667 if (IS_ERR(dev))
1668 return dev;
1669
1670 /* Configure flow based GRE device. */
1671 t = netdev_priv(dev);
1672 t->collect_md = true;
1673
1674 err = ipgre_newlink(net, dev, tb, NULL, NULL);
1675 if (err < 0) {
1676 free_netdev(dev);
1677 return ERR_PTR(err);
1678 }
1679
1680 /* openvswitch users expect packet sizes to be unrestricted,
1681 * so set the largest MTU we can.
1682 */
1683 err = __ip_tunnel_change_mtu(dev, IP_MAX_MTU, false);
1684 if (err)
1685 goto out;
1686
1687 err = rtnl_configure_link(dev, NULL);
1688 if (err < 0)
1689 goto out;
1690
1691 return dev;
1692 out:
1693 ip_tunnel_dellink(dev, &list_kill);
1694 unregister_netdevice_many(&list_kill);
1695 return ERR_PTR(err);
1696 }
1697 EXPORT_SYMBOL_GPL(gretap_fb_dev_create);
1698
ipgre_tap_init_net(struct net * net)1699 static int __net_init ipgre_tap_init_net(struct net *net)
1700 {
1701 return ip_tunnel_init_net(net, gre_tap_net_id, &ipgre_tap_ops, "gretap0");
1702 }
1703
ipgre_tap_exit_batch_net(struct list_head * list_net)1704 static void __net_exit ipgre_tap_exit_batch_net(struct list_head *list_net)
1705 {
1706 ip_tunnel_delete_nets(list_net, gre_tap_net_id, &ipgre_tap_ops);
1707 }
1708
1709 static struct pernet_operations ipgre_tap_net_ops = {
1710 .init = ipgre_tap_init_net,
1711 .exit_batch = ipgre_tap_exit_batch_net,
1712 .id = &gre_tap_net_id,
1713 .size = sizeof(struct ip_tunnel_net),
1714 };
1715
erspan_init_net(struct net * net)1716 static int __net_init erspan_init_net(struct net *net)
1717 {
1718 return ip_tunnel_init_net(net, erspan_net_id,
1719 &erspan_link_ops, "erspan0");
1720 }
1721
erspan_exit_batch_net(struct list_head * net_list)1722 static void __net_exit erspan_exit_batch_net(struct list_head *net_list)
1723 {
1724 ip_tunnel_delete_nets(net_list, erspan_net_id, &erspan_link_ops);
1725 }
1726
1727 static struct pernet_operations erspan_net_ops = {
1728 .init = erspan_init_net,
1729 .exit_batch = erspan_exit_batch_net,
1730 .id = &erspan_net_id,
1731 .size = sizeof(struct ip_tunnel_net),
1732 };
1733
ipgre_init(void)1734 static int __init ipgre_init(void)
1735 {
1736 int err;
1737
1738 pr_info("GRE over IPv4 tunneling driver\n");
1739
1740 err = register_pernet_device(&ipgre_net_ops);
1741 if (err < 0)
1742 return err;
1743
1744 err = register_pernet_device(&ipgre_tap_net_ops);
1745 if (err < 0)
1746 goto pnet_tap_failed;
1747
1748 err = register_pernet_device(&erspan_net_ops);
1749 if (err < 0)
1750 goto pnet_erspan_failed;
1751
1752 err = gre_add_protocol(&ipgre_protocol, GREPROTO_CISCO);
1753 if (err < 0) {
1754 pr_info("%s: can't add protocol\n", __func__);
1755 goto add_proto_failed;
1756 }
1757
1758 err = rtnl_link_register(&ipgre_link_ops);
1759 if (err < 0)
1760 goto rtnl_link_failed;
1761
1762 err = rtnl_link_register(&ipgre_tap_ops);
1763 if (err < 0)
1764 goto tap_ops_failed;
1765
1766 err = rtnl_link_register(&erspan_link_ops);
1767 if (err < 0)
1768 goto erspan_link_failed;
1769
1770 return 0;
1771
1772 erspan_link_failed:
1773 rtnl_link_unregister(&ipgre_tap_ops);
1774 tap_ops_failed:
1775 rtnl_link_unregister(&ipgre_link_ops);
1776 rtnl_link_failed:
1777 gre_del_protocol(&ipgre_protocol, GREPROTO_CISCO);
1778 add_proto_failed:
1779 unregister_pernet_device(&erspan_net_ops);
1780 pnet_erspan_failed:
1781 unregister_pernet_device(&ipgre_tap_net_ops);
1782 pnet_tap_failed:
1783 unregister_pernet_device(&ipgre_net_ops);
1784 return err;
1785 }
1786
ipgre_fini(void)1787 static void __exit ipgre_fini(void)
1788 {
1789 rtnl_link_unregister(&ipgre_tap_ops);
1790 rtnl_link_unregister(&ipgre_link_ops);
1791 rtnl_link_unregister(&erspan_link_ops);
1792 gre_del_protocol(&ipgre_protocol, GREPROTO_CISCO);
1793 unregister_pernet_device(&ipgre_tap_net_ops);
1794 unregister_pernet_device(&ipgre_net_ops);
1795 unregister_pernet_device(&erspan_net_ops);
1796 }
1797
1798 module_init(ipgre_init);
1799 module_exit(ipgre_fini);
1800 MODULE_LICENSE("GPL");
1801 MODULE_ALIAS_RTNL_LINK("gre");
1802 MODULE_ALIAS_RTNL_LINK("gretap");
1803 MODULE_ALIAS_RTNL_LINK("erspan");
1804 MODULE_ALIAS_NETDEV("gre0");
1805 MODULE_ALIAS_NETDEV("gretap0");
1806 MODULE_ALIAS_NETDEV("erspan0");
1807