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Merge tag 'pci-v6.16-fixes-3' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci
[linux-2.6-block.git] / net / ipv4 / ip_gre.c
... / ...
CommitLineData
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#include <net/inet_dscp.h>
48
49/*
50 Problems & solutions
51 --------------------
52
53 1. The most important issue is detecting local dead loops.
54 They would cause complete host lockup in transmit, which
55 would be "resolved" by stack overflow or, if queueing is enabled,
56 with infinite looping in net_bh.
57
58 We cannot track such dead loops during route installation,
59 it is infeasible task. The most general solutions would be
60 to keep skb->encapsulation counter (sort of local ttl),
61 and silently drop packet when it expires. It is a good
62 solution, but it supposes maintaining new variable in ALL
63 skb, even if no tunneling is used.
64
65 Current solution: xmit_recursion breaks dead loops. This is a percpu
66 counter, since when we enter the first ndo_xmit(), cpu migration is
67 forbidden. We force an exit if this counter reaches RECURSION_LIMIT
68
69 2. Networking dead loops would not kill routers, but would really
70 kill network. IP hop limit plays role of "t->recursion" in this case,
71 if we copy it from packet being encapsulated to upper header.
72 It is very good solution, but it introduces two problems:
73
74 - Routing protocols, using packets with ttl=1 (OSPF, RIP2),
75 do not work over tunnels.
76 - traceroute does not work. I planned to relay ICMP from tunnel,
77 so that this problem would be solved and traceroute output
78 would even more informative. This idea appeared to be wrong:
79 only Linux complies to rfc1812 now (yes, guys, Linux is the only
80 true router now :-)), all routers (at least, in neighbourhood of mine)
81 return only 8 bytes of payload. It is the end.
82
83 Hence, if we want that OSPF worked or traceroute said something reasonable,
84 we should search for another solution.
85
86 One of them is to parse packet trying to detect inner encapsulation
87 made by our node. It is difficult or even impossible, especially,
88 taking into account fragmentation. TO be short, ttl is not solution at all.
89
90 Current solution: The solution was UNEXPECTEDLY SIMPLE.
91 We force DF flag on tunnels with preconfigured hop limit,
92 that is ALL. :-) Well, it does not remove the problem completely,
93 but exponential growth of network traffic is changed to linear
94 (branches, that exceed pmtu are pruned) and tunnel mtu
95 rapidly degrades to value <68, where looping stops.
96 Yes, it is not good if there exists a router in the loop,
97 which does not force DF, even when encapsulating packets have DF set.
98 But it is not our problem! Nobody could accuse us, we made
99 all that we could make. Even if it is your gated who injected
100 fatal route to network, even if it were you who configured
101 fatal static route: you are innocent. :-)
102
103 Alexey Kuznetsov.
104 */
105
106static bool log_ecn_error = true;
107module_param(log_ecn_error, bool, 0644);
108MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN");
109
110static struct rtnl_link_ops ipgre_link_ops __read_mostly;
111static const struct header_ops ipgre_header_ops;
112
113static int ipgre_tunnel_init(struct net_device *dev);
114static void erspan_build_header(struct sk_buff *skb,
115 u32 id, u32 index,
116 bool truncate, bool is_ipv4);
117
118static unsigned int ipgre_net_id __read_mostly;
119static unsigned int gre_tap_net_id __read_mostly;
120static unsigned int erspan_net_id __read_mostly;
121
122static int ipgre_err(struct sk_buff *skb, u32 info,
123 const struct tnl_ptk_info *tpi)
124{
125
126 /* All the routers (except for Linux) return only
127 8 bytes of packet payload. It means, that precise relaying of
128 ICMP in the real Internet is absolutely infeasible.
129
130 Moreover, Cisco "wise men" put GRE key to the third word
131 in GRE header. It makes impossible maintaining even soft
132 state for keyed GRE tunnels with enabled checksum. Tell
133 them "thank you".
134
135 Well, I wonder, rfc1812 was written by Cisco employee,
136 what the hell these idiots break standards established
137 by themselves???
138 */
139 struct net *net = dev_net(skb->dev);
140 struct ip_tunnel_net *itn;
141 const struct iphdr *iph;
142 const int type = icmp_hdr(skb)->type;
143 const int code = icmp_hdr(skb)->code;
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 break;
185
186 case ICMP_REDIRECT:
187 break;
188 }
189
190#if IS_ENABLED(CONFIG_IPV6)
191 if (tpi->proto == htons(ETH_P_IPV6)) {
192 unsigned int data_len = 0;
193
194 if (type == ICMP_TIME_EXCEEDED)
195 data_len = icmp_hdr(skb)->un.reserved[1] * 4; /* RFC 4884 4.1 */
196
197 if (!ip6_err_gen_icmpv6_unreach(skb, iph->ihl * 4 + tpi->hdr_len,
198 type, data_len))
199 return 0;
200 }
201#endif
202
203 if (t->parms.iph.daddr == 0 ||
204 ipv4_is_multicast(t->parms.iph.daddr))
205 return 0;
206
207 if (t->parms.iph.ttl == 0 && type == ICMP_TIME_EXCEEDED)
208 return 0;
209
210 if (time_before(jiffies, t->err_time + IPTUNNEL_ERR_TIMEO))
211 t->err_count++;
212 else
213 t->err_count = 1;
214 t->err_time = jiffies;
215
216 return 0;
217}
218
219static void gre_err(struct sk_buff *skb, u32 info)
220{
221 /* All the routers (except for Linux) return only
222 * 8 bytes of packet payload. It means, that precise relaying of
223 * ICMP in the real Internet is absolutely infeasible.
224 *
225 * Moreover, Cisco "wise men" put GRE key to the third word
226 * in GRE header. It makes impossible maintaining even soft
227 * state for keyed
228 * GRE tunnels with enabled checksum. Tell them "thank you".
229 *
230 * Well, I wonder, rfc1812 was written by Cisco employee,
231 * what the hell these idiots break standards established
232 * by themselves???
233 */
234
235 const struct iphdr *iph = (struct iphdr *)skb->data;
236 const int type = icmp_hdr(skb)->type;
237 const int code = icmp_hdr(skb)->code;
238 struct tnl_ptk_info tpi;
239
240 if (gre_parse_header(skb, &tpi, NULL, htons(ETH_P_IP),
241 iph->ihl * 4) < 0)
242 return;
243
244 if (type == ICMP_DEST_UNREACH && code == ICMP_FRAG_NEEDED) {
245 ipv4_update_pmtu(skb, dev_net(skb->dev), info,
246 skb->dev->ifindex, IPPROTO_GRE);
247 return;
248 }
249 if (type == ICMP_REDIRECT) {
250 ipv4_redirect(skb, dev_net(skb->dev), skb->dev->ifindex,
251 IPPROTO_GRE);
252 return;
253 }
254
255 ipgre_err(skb, info, &tpi);
256}
257
258static bool is_erspan_type1(int gre_hdr_len)
259{
260 /* Both ERSPAN type I (version 0) and type II (version 1) use
261 * protocol 0x88BE, but the type I has only 4-byte GRE header,
262 * while type II has 8-byte.
263 */
264 return gre_hdr_len == 4;
265}
266
267static int erspan_rcv(struct sk_buff *skb, struct tnl_ptk_info *tpi,
268 int gre_hdr_len)
269{
270 struct net *net = dev_net(skb->dev);
271 struct metadata_dst *tun_dst = NULL;
272 struct erspan_base_hdr *ershdr;
273 IP_TUNNEL_DECLARE_FLAGS(flags);
274 struct ip_tunnel_net *itn;
275 struct ip_tunnel *tunnel;
276 const struct iphdr *iph;
277 struct erspan_md2 *md2;
278 int ver;
279 int len;
280
281 ip_tunnel_flags_copy(flags, tpi->flags);
282
283 itn = net_generic(net, erspan_net_id);
284 iph = ip_hdr(skb);
285 if (is_erspan_type1(gre_hdr_len)) {
286 ver = 0;
287 __set_bit(IP_TUNNEL_NO_KEY_BIT, flags);
288 tunnel = ip_tunnel_lookup(itn, skb->dev->ifindex, flags,
289 iph->saddr, iph->daddr, 0);
290 } else {
291 if (unlikely(!pskb_may_pull(skb,
292 gre_hdr_len + sizeof(*ershdr))))
293 return PACKET_REJECT;
294
295 ershdr = (struct erspan_base_hdr *)(skb->data + gre_hdr_len);
296 ver = ershdr->ver;
297 iph = ip_hdr(skb);
298 __set_bit(IP_TUNNEL_KEY_BIT, flags);
299 tunnel = ip_tunnel_lookup(itn, skb->dev->ifindex, flags,
300 iph->saddr, iph->daddr, tpi->key);
301 }
302
303 if (tunnel) {
304 if (is_erspan_type1(gre_hdr_len))
305 len = gre_hdr_len;
306 else
307 len = gre_hdr_len + erspan_hdr_len(ver);
308
309 if (unlikely(!pskb_may_pull(skb, len)))
310 return PACKET_REJECT;
311
312 if (__iptunnel_pull_header(skb,
313 len,
314 htons(ETH_P_TEB),
315 false, false) < 0)
316 goto drop;
317
318 if (tunnel->collect_md) {
319 struct erspan_metadata *pkt_md, *md;
320 struct ip_tunnel_info *info;
321 unsigned char *gh;
322 __be64 tun_id;
323
324 __set_bit(IP_TUNNEL_KEY_BIT, tpi->flags);
325 ip_tunnel_flags_copy(flags, tpi->flags);
326 tun_id = key32_to_tunnel_id(tpi->key);
327
328 tun_dst = ip_tun_rx_dst(skb, flags,
329 tun_id, sizeof(*md));
330 if (!tun_dst)
331 return PACKET_REJECT;
332
333 /* skb can be uncloned in __iptunnel_pull_header, so
334 * old pkt_md is no longer valid and we need to reset
335 * it
336 */
337 gh = skb_network_header(skb) +
338 skb_network_header_len(skb);
339 pkt_md = (struct erspan_metadata *)(gh + gre_hdr_len +
340 sizeof(*ershdr));
341 md = ip_tunnel_info_opts(&tun_dst->u.tun_info);
342 md->version = ver;
343 md2 = &md->u.md2;
344 memcpy(md2, pkt_md, ver == 1 ? ERSPAN_V1_MDSIZE :
345 ERSPAN_V2_MDSIZE);
346
347 info = &tun_dst->u.tun_info;
348 __set_bit(IP_TUNNEL_ERSPAN_OPT_BIT,
349 info->key.tun_flags);
350 info->options_len = sizeof(*md);
351 }
352
353 skb_reset_mac_header(skb);
354 ip_tunnel_rcv(tunnel, skb, tpi, tun_dst, log_ecn_error);
355 return PACKET_RCVD;
356 }
357 return PACKET_REJECT;
358
359drop:
360 kfree_skb(skb);
361 return PACKET_RCVD;
362}
363
364static int __ipgre_rcv(struct sk_buff *skb, const struct tnl_ptk_info *tpi,
365 struct ip_tunnel_net *itn, int hdr_len, bool raw_proto)
366{
367 struct metadata_dst *tun_dst = NULL;
368 const struct iphdr *iph;
369 struct ip_tunnel *tunnel;
370
371 iph = ip_hdr(skb);
372 tunnel = ip_tunnel_lookup(itn, skb->dev->ifindex, tpi->flags,
373 iph->saddr, iph->daddr, tpi->key);
374
375 if (tunnel) {
376 const struct iphdr *tnl_params;
377
378 if (__iptunnel_pull_header(skb, hdr_len, tpi->proto,
379 raw_proto, false) < 0)
380 goto drop;
381
382 /* Special case for ipgre_header_parse(), which expects the
383 * mac_header to point to the outer IP header.
384 */
385 if (tunnel->dev->header_ops == &ipgre_header_ops)
386 skb_pop_mac_header(skb);
387 else
388 skb_reset_mac_header(skb);
389
390 tnl_params = &tunnel->parms.iph;
391 if (tunnel->collect_md || tnl_params->daddr == 0) {
392 IP_TUNNEL_DECLARE_FLAGS(flags) = { };
393 __be64 tun_id;
394
395 __set_bit(IP_TUNNEL_CSUM_BIT, flags);
396 __set_bit(IP_TUNNEL_KEY_BIT, flags);
397 ip_tunnel_flags_and(flags, tpi->flags, flags);
398
399 tun_id = key32_to_tunnel_id(tpi->key);
400 tun_dst = ip_tun_rx_dst(skb, flags, tun_id, 0);
401 if (!tun_dst)
402 return PACKET_REJECT;
403 }
404
405 ip_tunnel_rcv(tunnel, skb, tpi, tun_dst, log_ecn_error);
406 return PACKET_RCVD;
407 }
408 return PACKET_NEXT;
409
410drop:
411 kfree_skb(skb);
412 return PACKET_RCVD;
413}
414
415static int ipgre_rcv(struct sk_buff *skb, const struct tnl_ptk_info *tpi,
416 int hdr_len)
417{
418 struct net *net = dev_net(skb->dev);
419 struct ip_tunnel_net *itn;
420 int res;
421
422 if (tpi->proto == htons(ETH_P_TEB))
423 itn = net_generic(net, gre_tap_net_id);
424 else
425 itn = net_generic(net, ipgre_net_id);
426
427 res = __ipgre_rcv(skb, tpi, itn, hdr_len, false);
428 if (res == PACKET_NEXT && tpi->proto == htons(ETH_P_TEB)) {
429 /* ipgre tunnels in collect metadata mode should receive
430 * also ETH_P_TEB traffic.
431 */
432 itn = net_generic(net, ipgre_net_id);
433 res = __ipgre_rcv(skb, tpi, itn, hdr_len, true);
434 }
435 return res;
436}
437
438static int gre_rcv(struct sk_buff *skb)
439{
440 struct tnl_ptk_info tpi;
441 bool csum_err = false;
442 int hdr_len;
443
444#ifdef CONFIG_NET_IPGRE_BROADCAST
445 if (ipv4_is_multicast(ip_hdr(skb)->daddr)) {
446 /* Looped back packet, drop it! */
447 if (rt_is_output_route(skb_rtable(skb)))
448 goto drop;
449 }
450#endif
451
452 hdr_len = gre_parse_header(skb, &tpi, &csum_err, htons(ETH_P_IP), 0);
453 if (hdr_len < 0)
454 goto drop;
455
456 if (unlikely(tpi.proto == htons(ETH_P_ERSPAN) ||
457 tpi.proto == htons(ETH_P_ERSPAN2))) {
458 if (erspan_rcv(skb, &tpi, hdr_len) == PACKET_RCVD)
459 return 0;
460 goto out;
461 }
462
463 if (ipgre_rcv(skb, &tpi, hdr_len) == PACKET_RCVD)
464 return 0;
465
466out:
467 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PORT_UNREACH, 0);
468drop:
469 kfree_skb(skb);
470 return 0;
471}
472
473static void __gre_xmit(struct sk_buff *skb, struct net_device *dev,
474 const struct iphdr *tnl_params,
475 __be16 proto)
476{
477 struct ip_tunnel *tunnel = netdev_priv(dev);
478 IP_TUNNEL_DECLARE_FLAGS(flags);
479
480 ip_tunnel_flags_copy(flags, tunnel->parms.o_flags);
481
482 /* Push GRE header. */
483 gre_build_header(skb, tunnel->tun_hlen,
484 flags, proto, tunnel->parms.o_key,
485 test_bit(IP_TUNNEL_SEQ_BIT, flags) ?
486 htonl(atomic_fetch_inc(&tunnel->o_seqno)) : 0);
487
488 ip_tunnel_xmit(skb, dev, tnl_params, tnl_params->protocol);
489}
490
491static int gre_handle_offloads(struct sk_buff *skb, bool csum)
492{
493 return iptunnel_handle_offloads(skb, csum ? SKB_GSO_GRE_CSUM : SKB_GSO_GRE);
494}
495
496static void gre_fb_xmit(struct sk_buff *skb, struct net_device *dev,
497 __be16 proto)
498{
499 struct ip_tunnel *tunnel = netdev_priv(dev);
500 IP_TUNNEL_DECLARE_FLAGS(flags) = { };
501 struct ip_tunnel_info *tun_info;
502 const struct ip_tunnel_key *key;
503 int tunnel_hlen;
504
505 tun_info = skb_tunnel_info(skb);
506 if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX) ||
507 ip_tunnel_info_af(tun_info) != AF_INET))
508 goto err_free_skb;
509
510 key = &tun_info->key;
511 tunnel_hlen = gre_calc_hlen(key->tun_flags);
512
513 if (skb_cow_head(skb, dev->needed_headroom))
514 goto err_free_skb;
515
516 /* Push Tunnel header. */
517 if (gre_handle_offloads(skb, test_bit(IP_TUNNEL_CSUM_BIT,
518 tunnel->parms.o_flags)))
519 goto err_free_skb;
520
521 __set_bit(IP_TUNNEL_CSUM_BIT, flags);
522 __set_bit(IP_TUNNEL_KEY_BIT, flags);
523 __set_bit(IP_TUNNEL_SEQ_BIT, flags);
524 ip_tunnel_flags_and(flags, tun_info->key.tun_flags, flags);
525
526 gre_build_header(skb, tunnel_hlen, flags, proto,
527 tunnel_id_to_key32(tun_info->key.tun_id),
528 test_bit(IP_TUNNEL_SEQ_BIT, flags) ?
529 htonl(atomic_fetch_inc(&tunnel->o_seqno)) : 0);
530
531 ip_md_tunnel_xmit(skb, dev, IPPROTO_GRE, tunnel_hlen);
532
533 return;
534
535err_free_skb:
536 kfree_skb(skb);
537 DEV_STATS_INC(dev, tx_dropped);
538}
539
540static void erspan_fb_xmit(struct sk_buff *skb, struct net_device *dev)
541{
542 struct ip_tunnel *tunnel = netdev_priv(dev);
543 IP_TUNNEL_DECLARE_FLAGS(flags) = { };
544 struct ip_tunnel_info *tun_info;
545 const struct ip_tunnel_key *key;
546 struct erspan_metadata *md;
547 bool truncate = false;
548 __be16 proto;
549 int tunnel_hlen;
550 int version;
551 int nhoff;
552
553 tun_info = skb_tunnel_info(skb);
554 if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX) ||
555 ip_tunnel_info_af(tun_info) != AF_INET))
556 goto err_free_skb;
557
558 key = &tun_info->key;
559 if (!test_bit(IP_TUNNEL_ERSPAN_OPT_BIT, tun_info->key.tun_flags))
560 goto err_free_skb;
561 if (tun_info->options_len < sizeof(*md))
562 goto err_free_skb;
563 md = ip_tunnel_info_opts(tun_info);
564
565 /* ERSPAN has fixed 8 byte GRE header */
566 version = md->version;
567 tunnel_hlen = 8 + erspan_hdr_len(version);
568
569 if (skb_cow_head(skb, dev->needed_headroom))
570 goto err_free_skb;
571
572 if (gre_handle_offloads(skb, false))
573 goto err_free_skb;
574
575 if (skb->len > dev->mtu + dev->hard_header_len) {
576 if (pskb_trim(skb, dev->mtu + dev->hard_header_len))
577 goto err_free_skb;
578 truncate = true;
579 }
580
581 nhoff = skb_network_offset(skb);
582 if (skb->protocol == htons(ETH_P_IP) &&
583 (ntohs(ip_hdr(skb)->tot_len) > skb->len - nhoff))
584 truncate = true;
585
586 if (skb->protocol == htons(ETH_P_IPV6)) {
587 int thoff;
588
589 if (skb_transport_header_was_set(skb))
590 thoff = skb_transport_offset(skb);
591 else
592 thoff = nhoff + sizeof(struct ipv6hdr);
593 if (ntohs(ipv6_hdr(skb)->payload_len) > skb->len - thoff)
594 truncate = true;
595 }
596
597 if (version == 1) {
598 erspan_build_header(skb, ntohl(tunnel_id_to_key32(key->tun_id)),
599 ntohl(md->u.index), truncate, true);
600 proto = htons(ETH_P_ERSPAN);
601 } else if (version == 2) {
602 erspan_build_header_v2(skb,
603 ntohl(tunnel_id_to_key32(key->tun_id)),
604 md->u.md2.dir,
605 get_hwid(&md->u.md2),
606 truncate, true);
607 proto = htons(ETH_P_ERSPAN2);
608 } else {
609 goto err_free_skb;
610 }
611
612 __set_bit(IP_TUNNEL_SEQ_BIT, flags);
613 gre_build_header(skb, 8, flags, proto, 0,
614 htonl(atomic_fetch_inc(&tunnel->o_seqno)));
615
616 ip_md_tunnel_xmit(skb, dev, IPPROTO_GRE, tunnel_hlen);
617
618 return;
619
620err_free_skb:
621 kfree_skb(skb);
622 DEV_STATS_INC(dev, tx_dropped);
623}
624
625static int gre_fill_metadata_dst(struct net_device *dev, struct sk_buff *skb)
626{
627 struct ip_tunnel_info *info = skb_tunnel_info(skb);
628 const struct ip_tunnel_key *key;
629 struct rtable *rt;
630 struct flowi4 fl4;
631
632 if (ip_tunnel_info_af(info) != AF_INET)
633 return -EINVAL;
634
635 key = &info->key;
636 ip_tunnel_init_flow(&fl4, IPPROTO_GRE, key->u.ipv4.dst, key->u.ipv4.src,
637 tunnel_id_to_key32(key->tun_id),
638 key->tos & ~INET_ECN_MASK, dev_net(dev), 0,
639 skb->mark, skb_get_hash(skb), key->flow_flags);
640 rt = ip_route_output_key(dev_net(dev), &fl4);
641 if (IS_ERR(rt))
642 return PTR_ERR(rt);
643
644 ip_rt_put(rt);
645 info->key.u.ipv4.src = fl4.saddr;
646 return 0;
647}
648
649static netdev_tx_t ipgre_xmit(struct sk_buff *skb,
650 struct net_device *dev)
651{
652 struct ip_tunnel *tunnel = netdev_priv(dev);
653 const struct iphdr *tnl_params;
654
655 if (!pskb_inet_may_pull(skb))
656 goto free_skb;
657
658 if (tunnel->collect_md) {
659 gre_fb_xmit(skb, dev, skb->protocol);
660 return NETDEV_TX_OK;
661 }
662
663 if (dev->header_ops) {
664 int pull_len = tunnel->hlen + sizeof(struct iphdr);
665
666 if (skb_cow_head(skb, 0))
667 goto free_skb;
668
669 if (!pskb_may_pull(skb, pull_len))
670 goto free_skb;
671
672 tnl_params = (const struct iphdr *)skb->data;
673
674 /* ip_tunnel_xmit() needs skb->data pointing to gre header. */
675 skb_pull(skb, pull_len);
676 skb_reset_mac_header(skb);
677
678 if (skb->ip_summed == CHECKSUM_PARTIAL &&
679 skb_checksum_start(skb) < skb->data)
680 goto free_skb;
681 } else {
682 if (skb_cow_head(skb, dev->needed_headroom))
683 goto free_skb;
684
685 tnl_params = &tunnel->parms.iph;
686 }
687
688 if (gre_handle_offloads(skb, test_bit(IP_TUNNEL_CSUM_BIT,
689 tunnel->parms.o_flags)))
690 goto free_skb;
691
692 __gre_xmit(skb, dev, tnl_params, skb->protocol);
693 return NETDEV_TX_OK;
694
695free_skb:
696 kfree_skb(skb);
697 DEV_STATS_INC(dev, tx_dropped);
698 return NETDEV_TX_OK;
699}
700
701static netdev_tx_t erspan_xmit(struct sk_buff *skb,
702 struct net_device *dev)
703{
704 struct ip_tunnel *tunnel = netdev_priv(dev);
705 bool truncate = false;
706 __be16 proto;
707
708 if (!pskb_inet_may_pull(skb))
709 goto free_skb;
710
711 if (tunnel->collect_md) {
712 erspan_fb_xmit(skb, dev);
713 return NETDEV_TX_OK;
714 }
715
716 if (gre_handle_offloads(skb, false))
717 goto free_skb;
718
719 if (skb_cow_head(skb, dev->needed_headroom))
720 goto free_skb;
721
722 if (skb->len > dev->mtu + dev->hard_header_len) {
723 if (pskb_trim(skb, dev->mtu + dev->hard_header_len))
724 goto free_skb;
725 truncate = true;
726 }
727
728 /* Push ERSPAN header */
729 if (tunnel->erspan_ver == 0) {
730 proto = htons(ETH_P_ERSPAN);
731 __clear_bit(IP_TUNNEL_SEQ_BIT, tunnel->parms.o_flags);
732 } else if (tunnel->erspan_ver == 1) {
733 erspan_build_header(skb, ntohl(tunnel->parms.o_key),
734 tunnel->index,
735 truncate, true);
736 proto = htons(ETH_P_ERSPAN);
737 } else if (tunnel->erspan_ver == 2) {
738 erspan_build_header_v2(skb, ntohl(tunnel->parms.o_key),
739 tunnel->dir, tunnel->hwid,
740 truncate, true);
741 proto = htons(ETH_P_ERSPAN2);
742 } else {
743 goto free_skb;
744 }
745
746 __clear_bit(IP_TUNNEL_KEY_BIT, tunnel->parms.o_flags);
747 __gre_xmit(skb, dev, &tunnel->parms.iph, proto);
748 return NETDEV_TX_OK;
749
750free_skb:
751 kfree_skb(skb);
752 DEV_STATS_INC(dev, tx_dropped);
753 return NETDEV_TX_OK;
754}
755
756static netdev_tx_t gre_tap_xmit(struct sk_buff *skb,
757 struct net_device *dev)
758{
759 struct ip_tunnel *tunnel = netdev_priv(dev);
760
761 if (!pskb_inet_may_pull(skb))
762 goto free_skb;
763
764 if (tunnel->collect_md) {
765 gre_fb_xmit(skb, dev, htons(ETH_P_TEB));
766 return NETDEV_TX_OK;
767 }
768
769 if (gre_handle_offloads(skb, test_bit(IP_TUNNEL_CSUM_BIT,
770 tunnel->parms.o_flags)))
771 goto free_skb;
772
773 if (skb_cow_head(skb, dev->needed_headroom))
774 goto free_skb;
775
776 __gre_xmit(skb, dev, &tunnel->parms.iph, htons(ETH_P_TEB));
777 return NETDEV_TX_OK;
778
779free_skb:
780 kfree_skb(skb);
781 DEV_STATS_INC(dev, tx_dropped);
782 return NETDEV_TX_OK;
783}
784
785static void ipgre_link_update(struct net_device *dev, bool set_mtu)
786{
787 struct ip_tunnel *tunnel = netdev_priv(dev);
788 int len;
789
790 len = tunnel->tun_hlen;
791 tunnel->tun_hlen = gre_calc_hlen(tunnel->parms.o_flags);
792 len = tunnel->tun_hlen - len;
793 tunnel->hlen = tunnel->hlen + len;
794
795 if (dev->header_ops)
796 dev->hard_header_len += len;
797 else
798 dev->needed_headroom += len;
799
800 if (set_mtu)
801 WRITE_ONCE(dev->mtu, max_t(int, dev->mtu - len, 68));
802
803 if (test_bit(IP_TUNNEL_SEQ_BIT, tunnel->parms.o_flags) ||
804 (test_bit(IP_TUNNEL_CSUM_BIT, tunnel->parms.o_flags) &&
805 tunnel->encap.type != TUNNEL_ENCAP_NONE)) {
806 dev->features &= ~NETIF_F_GSO_SOFTWARE;
807 dev->hw_features &= ~NETIF_F_GSO_SOFTWARE;
808 } else {
809 dev->features |= NETIF_F_GSO_SOFTWARE;
810 dev->hw_features |= NETIF_F_GSO_SOFTWARE;
811 }
812}
813
814static int ipgre_tunnel_ctl(struct net_device *dev,
815 struct ip_tunnel_parm_kern *p,
816 int cmd)
817{
818 __be16 i_flags, o_flags;
819 int err;
820
821 if (!ip_tunnel_flags_is_be16_compat(p->i_flags) ||
822 !ip_tunnel_flags_is_be16_compat(p->o_flags))
823 return -EOVERFLOW;
824
825 i_flags = ip_tunnel_flags_to_be16(p->i_flags);
826 o_flags = ip_tunnel_flags_to_be16(p->o_flags);
827
828 if (cmd == SIOCADDTUNNEL || cmd == SIOCCHGTUNNEL) {
829 if (p->iph.version != 4 || p->iph.protocol != IPPROTO_GRE ||
830 p->iph.ihl != 5 || (p->iph.frag_off & htons(~IP_DF)) ||
831 ((i_flags | o_flags) & (GRE_VERSION | GRE_ROUTING)))
832 return -EINVAL;
833 }
834
835 gre_flags_to_tnl_flags(p->i_flags, i_flags);
836 gre_flags_to_tnl_flags(p->o_flags, o_flags);
837
838 err = ip_tunnel_ctl(dev, p, cmd);
839 if (err)
840 return err;
841
842 if (cmd == SIOCCHGTUNNEL) {
843 struct ip_tunnel *t = netdev_priv(dev);
844
845 ip_tunnel_flags_copy(t->parms.i_flags, p->i_flags);
846 ip_tunnel_flags_copy(t->parms.o_flags, p->o_flags);
847
848 if (strcmp(dev->rtnl_link_ops->kind, "erspan"))
849 ipgre_link_update(dev, true);
850 }
851
852 i_flags = gre_tnl_flags_to_gre_flags(p->i_flags);
853 ip_tunnel_flags_from_be16(p->i_flags, i_flags);
854 o_flags = gre_tnl_flags_to_gre_flags(p->o_flags);
855 ip_tunnel_flags_from_be16(p->o_flags, o_flags);
856
857 return 0;
858}
859
860/* Nice toy. Unfortunately, useless in real life :-)
861 It allows to construct virtual multiprotocol broadcast "LAN"
862 over the Internet, provided multicast routing is tuned.
863
864
865 I have no idea was this bicycle invented before me,
866 so that I had to set ARPHRD_IPGRE to a random value.
867 I have an impression, that Cisco could make something similar,
868 but this feature is apparently missing in IOS<=11.2(8).
869
870 I set up 10.66.66/24 and fec0:6666:6666::0/96 as virtual networks
871 with broadcast 224.66.66.66. If you have access to mbone, play with me :-)
872
873 ping -t 255 224.66.66.66
874
875 If nobody answers, mbone does not work.
876
877 ip tunnel add Universe mode gre remote 224.66.66.66 local <Your_real_addr> ttl 255
878 ip addr add 10.66.66.<somewhat>/24 dev Universe
879 ifconfig Universe up
880 ifconfig Universe add fe80::<Your_real_addr>/10
881 ifconfig Universe add fec0:6666:6666::<Your_real_addr>/96
882 ftp 10.66.66.66
883 ...
884 ftp fec0:6666:6666::193.233.7.65
885 ...
886 */
887static int ipgre_header(struct sk_buff *skb, struct net_device *dev,
888 unsigned short type,
889 const void *daddr, const void *saddr, unsigned int len)
890{
891 struct ip_tunnel *t = netdev_priv(dev);
892 struct iphdr *iph;
893 struct gre_base_hdr *greh;
894
895 iph = skb_push(skb, t->hlen + sizeof(*iph));
896 greh = (struct gre_base_hdr *)(iph+1);
897 greh->flags = gre_tnl_flags_to_gre_flags(t->parms.o_flags);
898 greh->protocol = htons(type);
899
900 memcpy(iph, &t->parms.iph, sizeof(struct iphdr));
901
902 /* Set the source hardware address. */
903 if (saddr)
904 memcpy(&iph->saddr, saddr, 4);
905 if (daddr)
906 memcpy(&iph->daddr, daddr, 4);
907 if (iph->daddr)
908 return t->hlen + sizeof(*iph);
909
910 return -(t->hlen + sizeof(*iph));
911}
912
913static int ipgre_header_parse(const struct sk_buff *skb, unsigned char *haddr)
914{
915 const struct iphdr *iph = (const struct iphdr *) skb_mac_header(skb);
916 memcpy(haddr, &iph->saddr, 4);
917 return 4;
918}
919
920static const struct header_ops ipgre_header_ops = {
921 .create = ipgre_header,
922 .parse = ipgre_header_parse,
923};
924
925#ifdef CONFIG_NET_IPGRE_BROADCAST
926static int ipgre_open(struct net_device *dev)
927{
928 struct ip_tunnel *t = netdev_priv(dev);
929
930 if (ipv4_is_multicast(t->parms.iph.daddr)) {
931 struct flowi4 fl4 = {
932 .flowi4_oif = t->parms.link,
933 .flowi4_tos = inet_dscp_to_dsfield(ip4h_dscp(&t->parms.iph)),
934 .flowi4_scope = RT_SCOPE_UNIVERSE,
935 .flowi4_proto = IPPROTO_GRE,
936 .saddr = t->parms.iph.saddr,
937 .daddr = t->parms.iph.daddr,
938 .fl4_gre_key = t->parms.o_key,
939 };
940 struct rtable *rt;
941
942 rt = ip_route_output_key(t->net, &fl4);
943 if (IS_ERR(rt))
944 return -EADDRNOTAVAIL;
945 dev = rt->dst.dev;
946 ip_rt_put(rt);
947 if (!__in_dev_get_rtnl(dev))
948 return -EADDRNOTAVAIL;
949 t->mlink = dev->ifindex;
950 ip_mc_inc_group(__in_dev_get_rtnl(dev), t->parms.iph.daddr);
951 }
952 return 0;
953}
954
955static int ipgre_close(struct net_device *dev)
956{
957 struct ip_tunnel *t = netdev_priv(dev);
958
959 if (ipv4_is_multicast(t->parms.iph.daddr) && t->mlink) {
960 struct in_device *in_dev;
961 in_dev = inetdev_by_index(t->net, t->mlink);
962 if (in_dev)
963 ip_mc_dec_group(in_dev, t->parms.iph.daddr);
964 }
965 return 0;
966}
967#endif
968
969static const struct net_device_ops ipgre_netdev_ops = {
970 .ndo_init = ipgre_tunnel_init,
971 .ndo_uninit = ip_tunnel_uninit,
972#ifdef CONFIG_NET_IPGRE_BROADCAST
973 .ndo_open = ipgre_open,
974 .ndo_stop = ipgre_close,
975#endif
976 .ndo_start_xmit = ipgre_xmit,
977 .ndo_siocdevprivate = ip_tunnel_siocdevprivate,
978 .ndo_change_mtu = ip_tunnel_change_mtu,
979 .ndo_get_stats64 = dev_get_tstats64,
980 .ndo_get_iflink = ip_tunnel_get_iflink,
981 .ndo_tunnel_ctl = ipgre_tunnel_ctl,
982};
983
984#define GRE_FEATURES (NETIF_F_SG | \
985 NETIF_F_FRAGLIST | \
986 NETIF_F_HIGHDMA | \
987 NETIF_F_HW_CSUM)
988
989static void ipgre_tunnel_setup(struct net_device *dev)
990{
991 dev->netdev_ops = &ipgre_netdev_ops;
992 dev->type = ARPHRD_IPGRE;
993 ip_tunnel_setup(dev, ipgre_net_id);
994}
995
996static void __gre_tunnel_init(struct net_device *dev)
997{
998 struct ip_tunnel *tunnel;
999
1000 tunnel = netdev_priv(dev);
1001 tunnel->tun_hlen = gre_calc_hlen(tunnel->parms.o_flags);
1002 tunnel->parms.iph.protocol = IPPROTO_GRE;
1003
1004 tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen;
1005 dev->needed_headroom = tunnel->hlen + sizeof(tunnel->parms.iph);
1006
1007 dev->features |= GRE_FEATURES;
1008 dev->hw_features |= GRE_FEATURES;
1009
1010 /* TCP offload with GRE SEQ is not supported, nor can we support 2
1011 * levels of outer headers requiring an update.
1012 */
1013 if (test_bit(IP_TUNNEL_SEQ_BIT, tunnel->parms.o_flags))
1014 return;
1015 if (test_bit(IP_TUNNEL_CSUM_BIT, tunnel->parms.o_flags) &&
1016 tunnel->encap.type != TUNNEL_ENCAP_NONE)
1017 return;
1018
1019 dev->features |= NETIF_F_GSO_SOFTWARE;
1020 dev->hw_features |= NETIF_F_GSO_SOFTWARE;
1021
1022 dev->lltx = true;
1023}
1024
1025static int ipgre_tunnel_init(struct net_device *dev)
1026{
1027 struct ip_tunnel *tunnel = netdev_priv(dev);
1028 struct iphdr *iph = &tunnel->parms.iph;
1029
1030 __gre_tunnel_init(dev);
1031
1032 __dev_addr_set(dev, &iph->saddr, 4);
1033 memcpy(dev->broadcast, &iph->daddr, 4);
1034
1035 dev->flags = IFF_NOARP;
1036 netif_keep_dst(dev);
1037 dev->addr_len = 4;
1038
1039 if (iph->daddr && !tunnel->collect_md) {
1040#ifdef CONFIG_NET_IPGRE_BROADCAST
1041 if (ipv4_is_multicast(iph->daddr)) {
1042 if (!iph->saddr)
1043 return -EINVAL;
1044 dev->flags = IFF_BROADCAST;
1045 dev->header_ops = &ipgre_header_ops;
1046 dev->hard_header_len = tunnel->hlen + sizeof(*iph);
1047 dev->needed_headroom = 0;
1048 }
1049#endif
1050 } else if (!tunnel->collect_md) {
1051 dev->header_ops = &ipgre_header_ops;
1052 dev->hard_header_len = tunnel->hlen + sizeof(*iph);
1053 dev->needed_headroom = 0;
1054 }
1055
1056 return ip_tunnel_init(dev);
1057}
1058
1059static const struct gre_protocol ipgre_protocol = {
1060 .handler = gre_rcv,
1061 .err_handler = gre_err,
1062};
1063
1064static int __net_init ipgre_init_net(struct net *net)
1065{
1066 return ip_tunnel_init_net(net, ipgre_net_id, &ipgre_link_ops, NULL);
1067}
1068
1069static void __net_exit ipgre_exit_rtnl(struct net *net,
1070 struct list_head *dev_to_kill)
1071{
1072 ip_tunnel_delete_net(net, ipgre_net_id, &ipgre_link_ops, dev_to_kill);
1073}
1074
1075static struct pernet_operations ipgre_net_ops = {
1076 .init = ipgre_init_net,
1077 .exit_rtnl = ipgre_exit_rtnl,
1078 .id = &ipgre_net_id,
1079 .size = sizeof(struct ip_tunnel_net),
1080};
1081
1082static int ipgre_tunnel_validate(struct nlattr *tb[], struct nlattr *data[],
1083 struct netlink_ext_ack *extack)
1084{
1085 __be16 flags;
1086
1087 if (!data)
1088 return 0;
1089
1090 flags = 0;
1091 if (data[IFLA_GRE_IFLAGS])
1092 flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]);
1093 if (data[IFLA_GRE_OFLAGS])
1094 flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]);
1095 if (flags & (GRE_VERSION|GRE_ROUTING))
1096 return -EINVAL;
1097
1098 if (data[IFLA_GRE_COLLECT_METADATA] &&
1099 data[IFLA_GRE_ENCAP_TYPE] &&
1100 nla_get_u16(data[IFLA_GRE_ENCAP_TYPE]) != TUNNEL_ENCAP_NONE)
1101 return -EINVAL;
1102
1103 return 0;
1104}
1105
1106static int ipgre_tap_validate(struct nlattr *tb[], struct nlattr *data[],
1107 struct netlink_ext_ack *extack)
1108{
1109 __be32 daddr;
1110
1111 if (tb[IFLA_ADDRESS]) {
1112 if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
1113 return -EINVAL;
1114 if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
1115 return -EADDRNOTAVAIL;
1116 }
1117
1118 if (!data)
1119 goto out;
1120
1121 if (data[IFLA_GRE_REMOTE]) {
1122 memcpy(&daddr, nla_data(data[IFLA_GRE_REMOTE]), 4);
1123 if (!daddr)
1124 return -EINVAL;
1125 }
1126
1127out:
1128 return ipgre_tunnel_validate(tb, data, extack);
1129}
1130
1131static int erspan_validate(struct nlattr *tb[], struct nlattr *data[],
1132 struct netlink_ext_ack *extack)
1133{
1134 __be16 flags = 0;
1135 int ret;
1136
1137 if (!data)
1138 return 0;
1139
1140 ret = ipgre_tap_validate(tb, data, extack);
1141 if (ret)
1142 return ret;
1143
1144 if (data[IFLA_GRE_ERSPAN_VER] &&
1145 nla_get_u8(data[IFLA_GRE_ERSPAN_VER]) == 0)
1146 return 0;
1147
1148 /* ERSPAN type II/III should only have GRE sequence and key flag */
1149 if (data[IFLA_GRE_OFLAGS])
1150 flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]);
1151 if (data[IFLA_GRE_IFLAGS])
1152 flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]);
1153 if (!data[IFLA_GRE_COLLECT_METADATA] &&
1154 flags != (GRE_SEQ | GRE_KEY))
1155 return -EINVAL;
1156
1157 /* ERSPAN Session ID only has 10-bit. Since we reuse
1158 * 32-bit key field as ID, check it's range.
1159 */
1160 if (data[IFLA_GRE_IKEY] &&
1161 (ntohl(nla_get_be32(data[IFLA_GRE_IKEY])) & ~ID_MASK))
1162 return -EINVAL;
1163
1164 if (data[IFLA_GRE_OKEY] &&
1165 (ntohl(nla_get_be32(data[IFLA_GRE_OKEY])) & ~ID_MASK))
1166 return -EINVAL;
1167
1168 return 0;
1169}
1170
1171static int ipgre_netlink_parms(struct net_device *dev,
1172 struct nlattr *data[],
1173 struct nlattr *tb[],
1174 struct ip_tunnel_parm_kern *parms,
1175 __u32 *fwmark)
1176{
1177 struct ip_tunnel *t = netdev_priv(dev);
1178
1179 memset(parms, 0, sizeof(*parms));
1180
1181 parms->iph.protocol = IPPROTO_GRE;
1182
1183 if (!data)
1184 return 0;
1185
1186 if (data[IFLA_GRE_LINK])
1187 parms->link = nla_get_u32(data[IFLA_GRE_LINK]);
1188
1189 if (data[IFLA_GRE_IFLAGS])
1190 gre_flags_to_tnl_flags(parms->i_flags,
1191 nla_get_be16(data[IFLA_GRE_IFLAGS]));
1192
1193 if (data[IFLA_GRE_OFLAGS])
1194 gre_flags_to_tnl_flags(parms->o_flags,
1195 nla_get_be16(data[IFLA_GRE_OFLAGS]));
1196
1197 if (data[IFLA_GRE_IKEY])
1198 parms->i_key = nla_get_be32(data[IFLA_GRE_IKEY]);
1199
1200 if (data[IFLA_GRE_OKEY])
1201 parms->o_key = nla_get_be32(data[IFLA_GRE_OKEY]);
1202
1203 if (data[IFLA_GRE_LOCAL])
1204 parms->iph.saddr = nla_get_in_addr(data[IFLA_GRE_LOCAL]);
1205
1206 if (data[IFLA_GRE_REMOTE])
1207 parms->iph.daddr = nla_get_in_addr(data[IFLA_GRE_REMOTE]);
1208
1209 if (data[IFLA_GRE_TTL])
1210 parms->iph.ttl = nla_get_u8(data[IFLA_GRE_TTL]);
1211
1212 if (data[IFLA_GRE_TOS])
1213 parms->iph.tos = nla_get_u8(data[IFLA_GRE_TOS]);
1214
1215 if (!data[IFLA_GRE_PMTUDISC] || nla_get_u8(data[IFLA_GRE_PMTUDISC])) {
1216 if (t->ignore_df)
1217 return -EINVAL;
1218 parms->iph.frag_off = htons(IP_DF);
1219 }
1220
1221 if (data[IFLA_GRE_COLLECT_METADATA]) {
1222 t->collect_md = true;
1223 if (dev->type == ARPHRD_IPGRE)
1224 dev->type = ARPHRD_NONE;
1225 }
1226
1227 if (data[IFLA_GRE_IGNORE_DF]) {
1228 if (nla_get_u8(data[IFLA_GRE_IGNORE_DF])
1229 && (parms->iph.frag_off & htons(IP_DF)))
1230 return -EINVAL;
1231 t->ignore_df = !!nla_get_u8(data[IFLA_GRE_IGNORE_DF]);
1232 }
1233
1234 if (data[IFLA_GRE_FWMARK])
1235 *fwmark = nla_get_u32(data[IFLA_GRE_FWMARK]);
1236
1237 return 0;
1238}
1239
1240static int erspan_netlink_parms(struct net_device *dev,
1241 struct nlattr *data[],
1242 struct nlattr *tb[],
1243 struct ip_tunnel_parm_kern *parms,
1244 __u32 *fwmark)
1245{
1246 struct ip_tunnel *t = netdev_priv(dev);
1247 int err;
1248
1249 err = ipgre_netlink_parms(dev, data, tb, parms, fwmark);
1250 if (err)
1251 return err;
1252 if (!data)
1253 return 0;
1254
1255 if (data[IFLA_GRE_ERSPAN_VER]) {
1256 t->erspan_ver = nla_get_u8(data[IFLA_GRE_ERSPAN_VER]);
1257
1258 if (t->erspan_ver > 2)
1259 return -EINVAL;
1260 }
1261
1262 if (t->erspan_ver == 1) {
1263 if (data[IFLA_GRE_ERSPAN_INDEX]) {
1264 t->index = nla_get_u32(data[IFLA_GRE_ERSPAN_INDEX]);
1265 if (t->index & ~INDEX_MASK)
1266 return -EINVAL;
1267 }
1268 } else if (t->erspan_ver == 2) {
1269 if (data[IFLA_GRE_ERSPAN_DIR]) {
1270 t->dir = nla_get_u8(data[IFLA_GRE_ERSPAN_DIR]);
1271 if (t->dir & ~(DIR_MASK >> DIR_OFFSET))
1272 return -EINVAL;
1273 }
1274 if (data[IFLA_GRE_ERSPAN_HWID]) {
1275 t->hwid = nla_get_u16(data[IFLA_GRE_ERSPAN_HWID]);
1276 if (t->hwid & ~(HWID_MASK >> HWID_OFFSET))
1277 return -EINVAL;
1278 }
1279 }
1280
1281 return 0;
1282}
1283
1284/* This function returns true when ENCAP attributes are present in the nl msg */
1285static bool ipgre_netlink_encap_parms(struct nlattr *data[],
1286 struct ip_tunnel_encap *ipencap)
1287{
1288 bool ret = false;
1289
1290 memset(ipencap, 0, sizeof(*ipencap));
1291
1292 if (!data)
1293 return ret;
1294
1295 if (data[IFLA_GRE_ENCAP_TYPE]) {
1296 ret = true;
1297 ipencap->type = nla_get_u16(data[IFLA_GRE_ENCAP_TYPE]);
1298 }
1299
1300 if (data[IFLA_GRE_ENCAP_FLAGS]) {
1301 ret = true;
1302 ipencap->flags = nla_get_u16(data[IFLA_GRE_ENCAP_FLAGS]);
1303 }
1304
1305 if (data[IFLA_GRE_ENCAP_SPORT]) {
1306 ret = true;
1307 ipencap->sport = nla_get_be16(data[IFLA_GRE_ENCAP_SPORT]);
1308 }
1309
1310 if (data[IFLA_GRE_ENCAP_DPORT]) {
1311 ret = true;
1312 ipencap->dport = nla_get_be16(data[IFLA_GRE_ENCAP_DPORT]);
1313 }
1314
1315 return ret;
1316}
1317
1318static int gre_tap_init(struct net_device *dev)
1319{
1320 __gre_tunnel_init(dev);
1321 dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1322 netif_keep_dst(dev);
1323
1324 return ip_tunnel_init(dev);
1325}
1326
1327static const struct net_device_ops gre_tap_netdev_ops = {
1328 .ndo_init = gre_tap_init,
1329 .ndo_uninit = ip_tunnel_uninit,
1330 .ndo_start_xmit = gre_tap_xmit,
1331 .ndo_set_mac_address = eth_mac_addr,
1332 .ndo_validate_addr = eth_validate_addr,
1333 .ndo_change_mtu = ip_tunnel_change_mtu,
1334 .ndo_get_stats64 = dev_get_tstats64,
1335 .ndo_get_iflink = ip_tunnel_get_iflink,
1336 .ndo_fill_metadata_dst = gre_fill_metadata_dst,
1337};
1338
1339static int erspan_tunnel_init(struct net_device *dev)
1340{
1341 struct ip_tunnel *tunnel = netdev_priv(dev);
1342
1343 if (tunnel->erspan_ver == 0)
1344 tunnel->tun_hlen = 4; /* 4-byte GRE hdr. */
1345 else
1346 tunnel->tun_hlen = 8; /* 8-byte GRE hdr. */
1347
1348 tunnel->parms.iph.protocol = IPPROTO_GRE;
1349 tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen +
1350 erspan_hdr_len(tunnel->erspan_ver);
1351
1352 dev->features |= GRE_FEATURES;
1353 dev->hw_features |= GRE_FEATURES;
1354 dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1355 netif_keep_dst(dev);
1356
1357 return ip_tunnel_init(dev);
1358}
1359
1360static const struct net_device_ops erspan_netdev_ops = {
1361 .ndo_init = erspan_tunnel_init,
1362 .ndo_uninit = ip_tunnel_uninit,
1363 .ndo_start_xmit = erspan_xmit,
1364 .ndo_set_mac_address = eth_mac_addr,
1365 .ndo_validate_addr = eth_validate_addr,
1366 .ndo_change_mtu = ip_tunnel_change_mtu,
1367 .ndo_get_stats64 = dev_get_tstats64,
1368 .ndo_get_iflink = ip_tunnel_get_iflink,
1369 .ndo_fill_metadata_dst = gre_fill_metadata_dst,
1370};
1371
1372static void ipgre_tap_setup(struct net_device *dev)
1373{
1374 ether_setup(dev);
1375 dev->max_mtu = 0;
1376 dev->netdev_ops = &gre_tap_netdev_ops;
1377 dev->priv_flags &= ~IFF_TX_SKB_SHARING;
1378 dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1379 ip_tunnel_setup(dev, gre_tap_net_id);
1380}
1381
1382static int
1383ipgre_newlink_encap_setup(struct net_device *dev, struct nlattr *data[])
1384{
1385 struct ip_tunnel_encap ipencap;
1386
1387 if (ipgre_netlink_encap_parms(data, &ipencap)) {
1388 struct ip_tunnel *t = netdev_priv(dev);
1389 int err = ip_tunnel_encap_setup(t, &ipencap);
1390
1391 if (err < 0)
1392 return err;
1393 }
1394
1395 return 0;
1396}
1397
1398static int ipgre_newlink(struct net_device *dev,
1399 struct rtnl_newlink_params *params,
1400 struct netlink_ext_ack *extack)
1401{
1402 struct nlattr **data = params->data;
1403 struct nlattr **tb = params->tb;
1404 struct ip_tunnel_parm_kern p;
1405 __u32 fwmark = 0;
1406 int err;
1407
1408 err = ipgre_newlink_encap_setup(dev, data);
1409 if (err)
1410 return err;
1411
1412 err = ipgre_netlink_parms(dev, data, tb, &p, &fwmark);
1413 if (err < 0)
1414 return err;
1415 return ip_tunnel_newlink(params->link_net ? : dev_net(dev), dev, tb, &p,
1416 fwmark);
1417}
1418
1419static int erspan_newlink(struct net_device *dev,
1420 struct rtnl_newlink_params *params,
1421 struct netlink_ext_ack *extack)
1422{
1423 struct nlattr **data = params->data;
1424 struct nlattr **tb = params->tb;
1425 struct ip_tunnel_parm_kern p;
1426 __u32 fwmark = 0;
1427 int err;
1428
1429 err = ipgre_newlink_encap_setup(dev, data);
1430 if (err)
1431 return err;
1432
1433 err = erspan_netlink_parms(dev, data, tb, &p, &fwmark);
1434 if (err)
1435 return err;
1436 return ip_tunnel_newlink(params->link_net ? : dev_net(dev), dev, tb, &p,
1437 fwmark);
1438}
1439
1440static int ipgre_changelink(struct net_device *dev, struct nlattr *tb[],
1441 struct nlattr *data[],
1442 struct netlink_ext_ack *extack)
1443{
1444 struct ip_tunnel *t = netdev_priv(dev);
1445 struct ip_tunnel_parm_kern p;
1446 __u32 fwmark = t->fwmark;
1447 int err;
1448
1449 err = ipgre_newlink_encap_setup(dev, data);
1450 if (err)
1451 return err;
1452
1453 err = ipgre_netlink_parms(dev, data, tb, &p, &fwmark);
1454 if (err < 0)
1455 return err;
1456
1457 err = ip_tunnel_changelink(dev, tb, &p, fwmark);
1458 if (err < 0)
1459 return err;
1460
1461 ip_tunnel_flags_copy(t->parms.i_flags, p.i_flags);
1462 ip_tunnel_flags_copy(t->parms.o_flags, p.o_flags);
1463
1464 ipgre_link_update(dev, !tb[IFLA_MTU]);
1465
1466 return 0;
1467}
1468
1469static int erspan_changelink(struct net_device *dev, struct nlattr *tb[],
1470 struct nlattr *data[],
1471 struct netlink_ext_ack *extack)
1472{
1473 struct ip_tunnel *t = netdev_priv(dev);
1474 struct ip_tunnel_parm_kern p;
1475 __u32 fwmark = t->fwmark;
1476 int err;
1477
1478 err = ipgre_newlink_encap_setup(dev, data);
1479 if (err)
1480 return err;
1481
1482 err = erspan_netlink_parms(dev, data, tb, &p, &fwmark);
1483 if (err < 0)
1484 return err;
1485
1486 err = ip_tunnel_changelink(dev, tb, &p, fwmark);
1487 if (err < 0)
1488 return err;
1489
1490 ip_tunnel_flags_copy(t->parms.i_flags, p.i_flags);
1491 ip_tunnel_flags_copy(t->parms.o_flags, p.o_flags);
1492
1493 return 0;
1494}
1495
1496static size_t ipgre_get_size(const struct net_device *dev)
1497{
1498 return
1499 /* IFLA_GRE_LINK */
1500 nla_total_size(4) +
1501 /* IFLA_GRE_IFLAGS */
1502 nla_total_size(2) +
1503 /* IFLA_GRE_OFLAGS */
1504 nla_total_size(2) +
1505 /* IFLA_GRE_IKEY */
1506 nla_total_size(4) +
1507 /* IFLA_GRE_OKEY */
1508 nla_total_size(4) +
1509 /* IFLA_GRE_LOCAL */
1510 nla_total_size(4) +
1511 /* IFLA_GRE_REMOTE */
1512 nla_total_size(4) +
1513 /* IFLA_GRE_TTL */
1514 nla_total_size(1) +
1515 /* IFLA_GRE_TOS */
1516 nla_total_size(1) +
1517 /* IFLA_GRE_PMTUDISC */
1518 nla_total_size(1) +
1519 /* IFLA_GRE_ENCAP_TYPE */
1520 nla_total_size(2) +
1521 /* IFLA_GRE_ENCAP_FLAGS */
1522 nla_total_size(2) +
1523 /* IFLA_GRE_ENCAP_SPORT */
1524 nla_total_size(2) +
1525 /* IFLA_GRE_ENCAP_DPORT */
1526 nla_total_size(2) +
1527 /* IFLA_GRE_COLLECT_METADATA */
1528 nla_total_size(0) +
1529 /* IFLA_GRE_IGNORE_DF */
1530 nla_total_size(1) +
1531 /* IFLA_GRE_FWMARK */
1532 nla_total_size(4) +
1533 /* IFLA_GRE_ERSPAN_INDEX */
1534 nla_total_size(4) +
1535 /* IFLA_GRE_ERSPAN_VER */
1536 nla_total_size(1) +
1537 /* IFLA_GRE_ERSPAN_DIR */
1538 nla_total_size(1) +
1539 /* IFLA_GRE_ERSPAN_HWID */
1540 nla_total_size(2) +
1541 0;
1542}
1543
1544static int ipgre_fill_info(struct sk_buff *skb, const struct net_device *dev)
1545{
1546 struct ip_tunnel *t = netdev_priv(dev);
1547 struct ip_tunnel_parm_kern *p = &t->parms;
1548 IP_TUNNEL_DECLARE_FLAGS(o_flags);
1549
1550 ip_tunnel_flags_copy(o_flags, p->o_flags);
1551
1552 if (nla_put_u32(skb, IFLA_GRE_LINK, p->link) ||
1553 nla_put_be16(skb, IFLA_GRE_IFLAGS,
1554 gre_tnl_flags_to_gre_flags(p->i_flags)) ||
1555 nla_put_be16(skb, IFLA_GRE_OFLAGS,
1556 gre_tnl_flags_to_gre_flags(o_flags)) ||
1557 nla_put_be32(skb, IFLA_GRE_IKEY, p->i_key) ||
1558 nla_put_be32(skb, IFLA_GRE_OKEY, p->o_key) ||
1559 nla_put_in_addr(skb, IFLA_GRE_LOCAL, p->iph.saddr) ||
1560 nla_put_in_addr(skb, IFLA_GRE_REMOTE, p->iph.daddr) ||
1561 nla_put_u8(skb, IFLA_GRE_TTL, p->iph.ttl) ||
1562 nla_put_u8(skb, IFLA_GRE_TOS, p->iph.tos) ||
1563 nla_put_u8(skb, IFLA_GRE_PMTUDISC,
1564 !!(p->iph.frag_off & htons(IP_DF))) ||
1565 nla_put_u32(skb, IFLA_GRE_FWMARK, t->fwmark))
1566 goto nla_put_failure;
1567
1568 if (nla_put_u16(skb, IFLA_GRE_ENCAP_TYPE,
1569 t->encap.type) ||
1570 nla_put_be16(skb, IFLA_GRE_ENCAP_SPORT,
1571 t->encap.sport) ||
1572 nla_put_be16(skb, IFLA_GRE_ENCAP_DPORT,
1573 t->encap.dport) ||
1574 nla_put_u16(skb, IFLA_GRE_ENCAP_FLAGS,
1575 t->encap.flags))
1576 goto nla_put_failure;
1577
1578 if (nla_put_u8(skb, IFLA_GRE_IGNORE_DF, t->ignore_df))
1579 goto nla_put_failure;
1580
1581 if (t->collect_md) {
1582 if (nla_put_flag(skb, IFLA_GRE_COLLECT_METADATA))
1583 goto nla_put_failure;
1584 }
1585
1586 return 0;
1587
1588nla_put_failure:
1589 return -EMSGSIZE;
1590}
1591
1592static int erspan_fill_info(struct sk_buff *skb, const struct net_device *dev)
1593{
1594 struct ip_tunnel *t = netdev_priv(dev);
1595
1596 if (t->erspan_ver <= 2) {
1597 if (t->erspan_ver != 0 && !t->collect_md)
1598 __set_bit(IP_TUNNEL_KEY_BIT, t->parms.o_flags);
1599
1600 if (nla_put_u8(skb, IFLA_GRE_ERSPAN_VER, t->erspan_ver))
1601 goto nla_put_failure;
1602
1603 if (t->erspan_ver == 1) {
1604 if (nla_put_u32(skb, IFLA_GRE_ERSPAN_INDEX, t->index))
1605 goto nla_put_failure;
1606 } else if (t->erspan_ver == 2) {
1607 if (nla_put_u8(skb, IFLA_GRE_ERSPAN_DIR, t->dir))
1608 goto nla_put_failure;
1609 if (nla_put_u16(skb, IFLA_GRE_ERSPAN_HWID, t->hwid))
1610 goto nla_put_failure;
1611 }
1612 }
1613
1614 return ipgre_fill_info(skb, dev);
1615
1616nla_put_failure:
1617 return -EMSGSIZE;
1618}
1619
1620static void erspan_setup(struct net_device *dev)
1621{
1622 struct ip_tunnel *t = netdev_priv(dev);
1623
1624 ether_setup(dev);
1625 dev->max_mtu = 0;
1626 dev->netdev_ops = &erspan_netdev_ops;
1627 dev->priv_flags &= ~IFF_TX_SKB_SHARING;
1628 dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1629 ip_tunnel_setup(dev, erspan_net_id);
1630 t->erspan_ver = 1;
1631}
1632
1633static const struct nla_policy ipgre_policy[IFLA_GRE_MAX + 1] = {
1634 [IFLA_GRE_LINK] = { .type = NLA_U32 },
1635 [IFLA_GRE_IFLAGS] = { .type = NLA_U16 },
1636 [IFLA_GRE_OFLAGS] = { .type = NLA_U16 },
1637 [IFLA_GRE_IKEY] = { .type = NLA_U32 },
1638 [IFLA_GRE_OKEY] = { .type = NLA_U32 },
1639 [IFLA_GRE_LOCAL] = { .len = sizeof_field(struct iphdr, saddr) },
1640 [IFLA_GRE_REMOTE] = { .len = sizeof_field(struct iphdr, daddr) },
1641 [IFLA_GRE_TTL] = { .type = NLA_U8 },
1642 [IFLA_GRE_TOS] = { .type = NLA_U8 },
1643 [IFLA_GRE_PMTUDISC] = { .type = NLA_U8 },
1644 [IFLA_GRE_ENCAP_TYPE] = { .type = NLA_U16 },
1645 [IFLA_GRE_ENCAP_FLAGS] = { .type = NLA_U16 },
1646 [IFLA_GRE_ENCAP_SPORT] = { .type = NLA_U16 },
1647 [IFLA_GRE_ENCAP_DPORT] = { .type = NLA_U16 },
1648 [IFLA_GRE_COLLECT_METADATA] = { .type = NLA_FLAG },
1649 [IFLA_GRE_IGNORE_DF] = { .type = NLA_U8 },
1650 [IFLA_GRE_FWMARK] = { .type = NLA_U32 },
1651 [IFLA_GRE_ERSPAN_INDEX] = { .type = NLA_U32 },
1652 [IFLA_GRE_ERSPAN_VER] = { .type = NLA_U8 },
1653 [IFLA_GRE_ERSPAN_DIR] = { .type = NLA_U8 },
1654 [IFLA_GRE_ERSPAN_HWID] = { .type = NLA_U16 },
1655};
1656
1657static struct rtnl_link_ops ipgre_link_ops __read_mostly = {
1658 .kind = "gre",
1659 .maxtype = IFLA_GRE_MAX,
1660 .policy = ipgre_policy,
1661 .priv_size = sizeof(struct ip_tunnel),
1662 .setup = ipgre_tunnel_setup,
1663 .validate = ipgre_tunnel_validate,
1664 .newlink = ipgre_newlink,
1665 .changelink = ipgre_changelink,
1666 .dellink = ip_tunnel_dellink,
1667 .get_size = ipgre_get_size,
1668 .fill_info = ipgre_fill_info,
1669 .get_link_net = ip_tunnel_get_link_net,
1670};
1671
1672static struct rtnl_link_ops ipgre_tap_ops __read_mostly = {
1673 .kind = "gretap",
1674 .maxtype = IFLA_GRE_MAX,
1675 .policy = ipgre_policy,
1676 .priv_size = sizeof(struct ip_tunnel),
1677 .setup = ipgre_tap_setup,
1678 .validate = ipgre_tap_validate,
1679 .newlink = ipgre_newlink,
1680 .changelink = ipgre_changelink,
1681 .dellink = ip_tunnel_dellink,
1682 .get_size = ipgre_get_size,
1683 .fill_info = ipgre_fill_info,
1684 .get_link_net = ip_tunnel_get_link_net,
1685};
1686
1687static struct rtnl_link_ops erspan_link_ops __read_mostly = {
1688 .kind = "erspan",
1689 .maxtype = IFLA_GRE_MAX,
1690 .policy = ipgre_policy,
1691 .priv_size = sizeof(struct ip_tunnel),
1692 .setup = erspan_setup,
1693 .validate = erspan_validate,
1694 .newlink = erspan_newlink,
1695 .changelink = erspan_changelink,
1696 .dellink = ip_tunnel_dellink,
1697 .get_size = ipgre_get_size,
1698 .fill_info = erspan_fill_info,
1699 .get_link_net = ip_tunnel_get_link_net,
1700};
1701
1702struct net_device *gretap_fb_dev_create(struct net *net, const char *name,
1703 u8 name_assign_type)
1704{
1705 struct rtnl_newlink_params params = { .src_net = net };
1706 struct nlattr *tb[IFLA_MAX + 1];
1707 struct net_device *dev;
1708 LIST_HEAD(list_kill);
1709 struct ip_tunnel *t;
1710 int err;
1711
1712 memset(&tb, 0, sizeof(tb));
1713 params.tb = tb;
1714
1715 dev = rtnl_create_link(net, name, name_assign_type,
1716 &ipgre_tap_ops, tb, NULL);
1717 if (IS_ERR(dev))
1718 return dev;
1719
1720 /* Configure flow based GRE device. */
1721 t = netdev_priv(dev);
1722 t->collect_md = true;
1723
1724 err = ipgre_newlink(dev, &params, NULL);
1725 if (err < 0) {
1726 free_netdev(dev);
1727 return ERR_PTR(err);
1728 }
1729
1730 /* openvswitch users expect packet sizes to be unrestricted,
1731 * so set the largest MTU we can.
1732 */
1733 err = __ip_tunnel_change_mtu(dev, IP_MAX_MTU, false);
1734 if (err)
1735 goto out;
1736
1737 err = rtnl_configure_link(dev, NULL, 0, NULL);
1738 if (err < 0)
1739 goto out;
1740
1741 return dev;
1742out:
1743 ip_tunnel_dellink(dev, &list_kill);
1744 unregister_netdevice_many(&list_kill);
1745 return ERR_PTR(err);
1746}
1747EXPORT_SYMBOL_GPL(gretap_fb_dev_create);
1748
1749static int __net_init ipgre_tap_init_net(struct net *net)
1750{
1751 return ip_tunnel_init_net(net, gre_tap_net_id, &ipgre_tap_ops, "gretap0");
1752}
1753
1754static void __net_exit ipgre_tap_exit_rtnl(struct net *net,
1755 struct list_head *dev_to_kill)
1756{
1757 ip_tunnel_delete_net(net, gre_tap_net_id, &ipgre_tap_ops, dev_to_kill);
1758}
1759
1760static struct pernet_operations ipgre_tap_net_ops = {
1761 .init = ipgre_tap_init_net,
1762 .exit_rtnl = ipgre_tap_exit_rtnl,
1763 .id = &gre_tap_net_id,
1764 .size = sizeof(struct ip_tunnel_net),
1765};
1766
1767static int __net_init erspan_init_net(struct net *net)
1768{
1769 return ip_tunnel_init_net(net, erspan_net_id,
1770 &erspan_link_ops, "erspan0");
1771}
1772
1773static void __net_exit erspan_exit_rtnl(struct net *net,
1774 struct list_head *dev_to_kill)
1775{
1776 ip_tunnel_delete_net(net, erspan_net_id, &erspan_link_ops, dev_to_kill);
1777}
1778
1779static struct pernet_operations erspan_net_ops = {
1780 .init = erspan_init_net,
1781 .exit_rtnl = erspan_exit_rtnl,
1782 .id = &erspan_net_id,
1783 .size = sizeof(struct ip_tunnel_net),
1784};
1785
1786static int __init ipgre_init(void)
1787{
1788 int err;
1789
1790 pr_info("GRE over IPv4 tunneling driver\n");
1791
1792 err = register_pernet_device(&ipgre_net_ops);
1793 if (err < 0)
1794 return err;
1795
1796 err = register_pernet_device(&ipgre_tap_net_ops);
1797 if (err < 0)
1798 goto pnet_tap_failed;
1799
1800 err = register_pernet_device(&erspan_net_ops);
1801 if (err < 0)
1802 goto pnet_erspan_failed;
1803
1804 err = gre_add_protocol(&ipgre_protocol, GREPROTO_CISCO);
1805 if (err < 0) {
1806 pr_info("%s: can't add protocol\n", __func__);
1807 goto add_proto_failed;
1808 }
1809
1810 err = rtnl_link_register(&ipgre_link_ops);
1811 if (err < 0)
1812 goto rtnl_link_failed;
1813
1814 err = rtnl_link_register(&ipgre_tap_ops);
1815 if (err < 0)
1816 goto tap_ops_failed;
1817
1818 err = rtnl_link_register(&erspan_link_ops);
1819 if (err < 0)
1820 goto erspan_link_failed;
1821
1822 return 0;
1823
1824erspan_link_failed:
1825 rtnl_link_unregister(&ipgre_tap_ops);
1826tap_ops_failed:
1827 rtnl_link_unregister(&ipgre_link_ops);
1828rtnl_link_failed:
1829 gre_del_protocol(&ipgre_protocol, GREPROTO_CISCO);
1830add_proto_failed:
1831 unregister_pernet_device(&erspan_net_ops);
1832pnet_erspan_failed:
1833 unregister_pernet_device(&ipgre_tap_net_ops);
1834pnet_tap_failed:
1835 unregister_pernet_device(&ipgre_net_ops);
1836 return err;
1837}
1838
1839static void __exit ipgre_fini(void)
1840{
1841 rtnl_link_unregister(&ipgre_tap_ops);
1842 rtnl_link_unregister(&ipgre_link_ops);
1843 rtnl_link_unregister(&erspan_link_ops);
1844 gre_del_protocol(&ipgre_protocol, GREPROTO_CISCO);
1845 unregister_pernet_device(&ipgre_tap_net_ops);
1846 unregister_pernet_device(&ipgre_net_ops);
1847 unregister_pernet_device(&erspan_net_ops);
1848}
1849
1850module_init(ipgre_init);
1851module_exit(ipgre_fini);
1852MODULE_DESCRIPTION("IPv4 GRE tunnels over IP library");
1853MODULE_LICENSE("GPL");
1854MODULE_ALIAS_RTNL_LINK("gre");
1855MODULE_ALIAS_RTNL_LINK("gretap");
1856MODULE_ALIAS_RTNL_LINK("erspan");
1857MODULE_ALIAS_NETDEV("gre0");
1858MODULE_ALIAS_NETDEV("gretap0");
1859MODULE_ALIAS_NETDEV("erspan0");
Linux 6.x block layer and io_uring tree(s)