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octeontx2-pf: Fix error return code in otx2_probe()
[linux/fpc-iii.git] / net / ipv4 / ip_gre.c
blob029b24eeafbaf8ec28b0f55ff08de58b8fb0efdd
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 int ipgre_tunnel_init(struct net_device *dev);
111 static void erspan_build_header(struct sk_buff *skb,
112 u32 id, u32 index,
113 bool truncate, bool is_ipv4);
114
115 static unsigned int ipgre_net_id __read_mostly;
116 static unsigned int gre_tap_net_id __read_mostly;
117 static unsigned int erspan_net_id __read_mostly;
118
119 static int ipgre_err(struct sk_buff *skb, u32 info,
120 const struct tnl_ptk_info *tpi)
121 {
122
123 /* All the routers (except for Linux) return only
124 8 bytes of packet payload. It means, that precise relaying of
125 ICMP in the real Internet is absolutely infeasible.
126
127 Moreover, Cisco "wise men" put GRE key to the third word
128 in GRE header. It makes impossible maintaining even soft
129 state for keyed GRE tunnels with enabled checksum. Tell
130 them "thank you".
131
132 Well, I wonder, rfc1812 was written by Cisco employee,
133 what the hell these idiots break standards established
134 by themselves???
135 */
136 struct net *net = dev_net(skb->dev);
137 struct ip_tunnel_net *itn;
138 const struct iphdr *iph;
139 const int type = icmp_hdr(skb)->type;
140 const int code = icmp_hdr(skb)->code;
141 unsigned int data_len = 0;
142 struct ip_tunnel *t;
143
144 if (tpi->proto == htons(ETH_P_TEB))
145 itn = net_generic(net, gre_tap_net_id);
146 else if (tpi->proto == htons(ETH_P_ERSPAN) ||
147 tpi->proto == htons(ETH_P_ERSPAN2))
148 itn = net_generic(net, erspan_net_id);
149 else
150 itn = net_generic(net, ipgre_net_id);
151
152 iph = (const struct iphdr *)(icmp_hdr(skb) + 1);
153 t = ip_tunnel_lookup(itn, skb->dev->ifindex, tpi->flags,
154 iph->daddr, iph->saddr, tpi->key);
155
156 if (!t)
157 return -ENOENT;
158
159 switch (type) {
160 default:
161 case ICMP_PARAMETERPROB:
162 return 0;
163
164 case ICMP_DEST_UNREACH:
165 switch (code) {
166 case ICMP_SR_FAILED:
167 case ICMP_PORT_UNREACH:
168 /* Impossible event. */
169 return 0;
170 default:
171 /* All others are translated to HOST_UNREACH.
172 rfc2003 contains "deep thoughts" about NET_UNREACH,
173 I believe they are just ether pollution. --ANK
174 */
175 break;
176 }
177 break;
178
179 case ICMP_TIME_EXCEEDED:
180 if (code != ICMP_EXC_TTL)
181 return 0;
182 data_len = icmp_hdr(skb)->un.reserved[1] * 4; /* RFC 4884 4.1 */
183 break;
184
185 case ICMP_REDIRECT:
186 break;
187 }
188
189 #if IS_ENABLED(CONFIG_IPV6)
190 if (tpi->proto == htons(ETH_P_IPV6) &&
191 !ip6_err_gen_icmpv6_unreach(skb, iph->ihl * 4 + tpi->hdr_len,
192 type, data_len))
193 return 0;
194 #endif
195
196 if (t->parms.iph.daddr == 0 ||
197 ipv4_is_multicast(t->parms.iph.daddr))
198 return 0;
199
200 if (t->parms.iph.ttl == 0 && type == ICMP_TIME_EXCEEDED)
201 return 0;
202
203 if (time_before(jiffies, t->err_time + IPTUNNEL_ERR_TIMEO))
204 t->err_count++;
205 else
206 t->err_count = 1;
207 t->err_time = jiffies;
208
209 return 0;
210 }
211
212 static void gre_err(struct sk_buff *skb, u32 info)
213 {
214 /* All the routers (except for Linux) return only
215 * 8 bytes of packet payload. It means, that precise relaying of
216 * ICMP in the real Internet is absolutely infeasible.
217 *
218 * Moreover, Cisco "wise men" put GRE key to the third word
219 * in GRE header. It makes impossible maintaining even soft
220 * state for keyed
221 * GRE tunnels with enabled checksum. Tell them "thank you".
222 *
223 * Well, I wonder, rfc1812 was written by Cisco employee,
224 * what the hell these idiots break standards established
225 * by themselves???
226 */
227
228 const struct iphdr *iph = (struct iphdr *)skb->data;
229 const int type = icmp_hdr(skb)->type;
230 const int code = icmp_hdr(skb)->code;
231 struct tnl_ptk_info tpi;
232
233 if (gre_parse_header(skb, &tpi, NULL, htons(ETH_P_IP),
234 iph->ihl * 4) < 0)
235 return;
236
237 if (type == ICMP_DEST_UNREACH && code == ICMP_FRAG_NEEDED) {
238 ipv4_update_pmtu(skb, dev_net(skb->dev), info,
239 skb->dev->ifindex, IPPROTO_GRE);
240 return;
241 }
242 if (type == ICMP_REDIRECT) {
243 ipv4_redirect(skb, dev_net(skb->dev), skb->dev->ifindex,
244 IPPROTO_GRE);
245 return;
246 }
247
248 ipgre_err(skb, info, &tpi);
249 }
250
251 static int erspan_rcv(struct sk_buff *skb, struct tnl_ptk_info *tpi,
252 int gre_hdr_len)
253 {
254 struct net *net = dev_net(skb->dev);
255 struct metadata_dst *tun_dst = NULL;
256 struct erspan_base_hdr *ershdr;
257 struct ip_tunnel_net *itn;
258 struct ip_tunnel *tunnel;
259 const struct iphdr *iph;
260 struct erspan_md2 *md2;
261 int ver;
262 int len;
263
264 itn = net_generic(net, erspan_net_id);
265
266 iph = ip_hdr(skb);
267 ershdr = (struct erspan_base_hdr *)(skb->data + gre_hdr_len);
268 ver = ershdr->ver;
269
270 tunnel = ip_tunnel_lookup(itn, skb->dev->ifindex,
271 tpi->flags | TUNNEL_KEY,
272 iph->saddr, iph->daddr, tpi->key);
273
274 if (tunnel) {
275 len = gre_hdr_len + erspan_hdr_len(ver);
276 if (unlikely(!pskb_may_pull(skb, len)))
277 return PACKET_REJECT;
278
279 if (__iptunnel_pull_header(skb,
280 len,
281 htons(ETH_P_TEB),
282 false, false) < 0)
283 goto drop;
284
285 if (tunnel->collect_md) {
286 struct erspan_metadata *pkt_md, *md;
287 struct ip_tunnel_info *info;
288 unsigned char *gh;
289 __be64 tun_id;
290 __be16 flags;
291
292 tpi->flags |= TUNNEL_KEY;
293 flags = tpi->flags;
294 tun_id = key32_to_tunnel_id(tpi->key);
295
296 tun_dst = ip_tun_rx_dst(skb, flags,
297 tun_id, sizeof(*md));
298 if (!tun_dst)
299 return PACKET_REJECT;
300
301 /* skb can be uncloned in __iptunnel_pull_header, so
302 * old pkt_md is no longer valid and we need to reset
303 * it
304 */
305 gh = skb_network_header(skb) +
306 skb_network_header_len(skb);
307 pkt_md = (struct erspan_metadata *)(gh + gre_hdr_len +
308 sizeof(*ershdr));
309 md = ip_tunnel_info_opts(&tun_dst->u.tun_info);
310 md->version = ver;
311 md2 = &md->u.md2;
312 memcpy(md2, pkt_md, ver == 1 ? ERSPAN_V1_MDSIZE :
313 ERSPAN_V2_MDSIZE);
314
315 info = &tun_dst->u.tun_info;
316 info->key.tun_flags |= TUNNEL_ERSPAN_OPT;
317 info->options_len = sizeof(*md);
318 }
319
320 skb_reset_mac_header(skb);
321 ip_tunnel_rcv(tunnel, skb, tpi, tun_dst, log_ecn_error);
322 return PACKET_RCVD;
323 }
324 return PACKET_REJECT;
325
326 drop:
327 kfree_skb(skb);
328 return PACKET_RCVD;
329 }
330
331 static int __ipgre_rcv(struct sk_buff *skb, const struct tnl_ptk_info *tpi,
332 struct ip_tunnel_net *itn, int hdr_len, bool raw_proto)
333 {
334 struct metadata_dst *tun_dst = NULL;
335 const struct iphdr *iph;
336 struct ip_tunnel *tunnel;
337
338 iph = ip_hdr(skb);
339 tunnel = ip_tunnel_lookup(itn, skb->dev->ifindex, tpi->flags,
340 iph->saddr, iph->daddr, tpi->key);
341
342 if (tunnel) {
343 const struct iphdr *tnl_params;
344
345 if (__iptunnel_pull_header(skb, hdr_len, tpi->proto,
346 raw_proto, false) < 0)
347 goto drop;
348
349 if (tunnel->dev->type != ARPHRD_NONE)
350 skb_pop_mac_header(skb);
351 else
352 skb_reset_mac_header(skb);
353
354 tnl_params = &tunnel->parms.iph;
355 if (tunnel->collect_md || tnl_params->daddr == 0) {
356 __be16 flags;
357 __be64 tun_id;
358
359 flags = tpi->flags & (TUNNEL_CSUM | TUNNEL_KEY);
360 tun_id = key32_to_tunnel_id(tpi->key);
361 tun_dst = ip_tun_rx_dst(skb, flags, tun_id, 0);
362 if (!tun_dst)
363 return PACKET_REJECT;
364 }
365
366 ip_tunnel_rcv(tunnel, skb, tpi, tun_dst, log_ecn_error);
367 return PACKET_RCVD;
368 }
369 return PACKET_NEXT;
370
371 drop:
372 kfree_skb(skb);
373 return PACKET_RCVD;
374 }
375
376 static int ipgre_rcv(struct sk_buff *skb, const struct tnl_ptk_info *tpi,
377 int hdr_len)
378 {
379 struct net *net = dev_net(skb->dev);
380 struct ip_tunnel_net *itn;
381 int res;
382
383 if (tpi->proto == htons(ETH_P_TEB))
384 itn = net_generic(net, gre_tap_net_id);
385 else
386 itn = net_generic(net, ipgre_net_id);
387
388 res = __ipgre_rcv(skb, tpi, itn, hdr_len, false);
389 if (res == PACKET_NEXT && tpi->proto == htons(ETH_P_TEB)) {
390 /* ipgre tunnels in collect metadata mode should receive
391 * also ETH_P_TEB traffic.
392 */
393 itn = net_generic(net, ipgre_net_id);
394 res = __ipgre_rcv(skb, tpi, itn, hdr_len, true);
395 }
396 return res;
397 }
398
399 static int gre_rcv(struct sk_buff *skb)
400 {
401 struct tnl_ptk_info tpi;
402 bool csum_err = false;
403 int hdr_len;
404
405 #ifdef CONFIG_NET_IPGRE_BROADCAST
406 if (ipv4_is_multicast(ip_hdr(skb)->daddr)) {
407 /* Looped back packet, drop it! */
408 if (rt_is_output_route(skb_rtable(skb)))
409 goto drop;
410 }
411 #endif
412
413 hdr_len = gre_parse_header(skb, &tpi, &csum_err, htons(ETH_P_IP), 0);
414 if (hdr_len < 0)
415 goto drop;
416
417 if (unlikely(tpi.proto == htons(ETH_P_ERSPAN) ||
418 tpi.proto == htons(ETH_P_ERSPAN2))) {
419 if (erspan_rcv(skb, &tpi, hdr_len) == PACKET_RCVD)
420 return 0;
421 goto out;
422 }
423
424 if (ipgre_rcv(skb, &tpi, hdr_len) == PACKET_RCVD)
425 return 0;
426
427 out:
428 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PORT_UNREACH, 0);
429 drop:
430 kfree_skb(skb);
431 return 0;
432 }
433
434 static void __gre_xmit(struct sk_buff *skb, struct net_device *dev,
435 const struct iphdr *tnl_params,
436 __be16 proto)
437 {
438 struct ip_tunnel *tunnel = netdev_priv(dev);
439
440 if (tunnel->parms.o_flags & TUNNEL_SEQ)
441 tunnel->o_seqno++;
442
443 /* Push GRE header. */
444 gre_build_header(skb, tunnel->tun_hlen,
445 tunnel->parms.o_flags, proto, tunnel->parms.o_key,
446 htonl(tunnel->o_seqno));
447
448 ip_tunnel_xmit(skb, dev, tnl_params, tnl_params->protocol);
449 }
450
451 static int gre_handle_offloads(struct sk_buff *skb, bool csum)
452 {
453 return iptunnel_handle_offloads(skb, csum ? SKB_GSO_GRE_CSUM : SKB_GSO_GRE);
454 }
455
456 static void gre_fb_xmit(struct sk_buff *skb, struct net_device *dev,
457 __be16 proto)
458 {
459 struct ip_tunnel *tunnel = netdev_priv(dev);
460 struct ip_tunnel_info *tun_info;
461 const struct ip_tunnel_key *key;
462 int tunnel_hlen;
463 __be16 flags;
464
465 tun_info = skb_tunnel_info(skb);
466 if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX) ||
467 ip_tunnel_info_af(tun_info) != AF_INET))
468 goto err_free_skb;
469
470 key = &tun_info->key;
471 tunnel_hlen = gre_calc_hlen(key->tun_flags);
472
473 if (skb_cow_head(skb, dev->needed_headroom))
474 goto err_free_skb;
475
476 /* Push Tunnel header. */
477 if (gre_handle_offloads(skb, !!(tun_info->key.tun_flags & TUNNEL_CSUM)))
478 goto err_free_skb;
479
480 flags = tun_info->key.tun_flags &
481 (TUNNEL_CSUM | TUNNEL_KEY | TUNNEL_SEQ);
482 gre_build_header(skb, tunnel_hlen, flags, proto,
483 tunnel_id_to_key32(tun_info->key.tun_id),
484 (flags & TUNNEL_SEQ) ? htonl(tunnel->o_seqno++) : 0);
485
486 ip_md_tunnel_xmit(skb, dev, IPPROTO_GRE, tunnel_hlen);
487
488 return;
489
490 err_free_skb:
491 kfree_skb(skb);
492 dev->stats.tx_dropped++;
493 }
494
495 static void erspan_fb_xmit(struct sk_buff *skb, struct net_device *dev)
496 {
497 struct ip_tunnel *tunnel = netdev_priv(dev);
498 struct ip_tunnel_info *tun_info;
499 const struct ip_tunnel_key *key;
500 struct erspan_metadata *md;
501 bool truncate = false;
502 __be16 proto;
503 int tunnel_hlen;
504 int version;
505 int nhoff;
506 int thoff;
507
508 tun_info = skb_tunnel_info(skb);
509 if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX) ||
510 ip_tunnel_info_af(tun_info) != AF_INET))
511 goto err_free_skb;
512
513 key = &tun_info->key;
514 if (!(tun_info->key.tun_flags & TUNNEL_ERSPAN_OPT))
515 goto err_free_skb;
516 if (tun_info->options_len < sizeof(*md))
517 goto err_free_skb;
518 md = ip_tunnel_info_opts(tun_info);
519
520 /* ERSPAN has fixed 8 byte GRE header */
521 version = md->version;
522 tunnel_hlen = 8 + erspan_hdr_len(version);
523
524 if (skb_cow_head(skb, dev->needed_headroom))
525 goto err_free_skb;
526
527 if (gre_handle_offloads(skb, false))
528 goto err_free_skb;
529
530 if (skb->len > dev->mtu + dev->hard_header_len) {
531 pskb_trim(skb, dev->mtu + dev->hard_header_len);
532 truncate = true;
533 }
534
535 nhoff = skb_network_header(skb) - skb_mac_header(skb);
536 if (skb->protocol == htons(ETH_P_IP) &&
537 (ntohs(ip_hdr(skb)->tot_len) > skb->len - nhoff))
538 truncate = true;
539
540 thoff = skb_transport_header(skb) - skb_mac_header(skb);
541 if (skb->protocol == htons(ETH_P_IPV6) &&
542 (ntohs(ipv6_hdr(skb)->payload_len) > skb->len - thoff))
543 truncate = true;
544
545 if (version == 1) {
546 erspan_build_header(skb, ntohl(tunnel_id_to_key32(key->tun_id)),
547 ntohl(md->u.index), truncate, true);
548 proto = htons(ETH_P_ERSPAN);
549 } else if (version == 2) {
550 erspan_build_header_v2(skb,
551 ntohl(tunnel_id_to_key32(key->tun_id)),
552 md->u.md2.dir,
553 get_hwid(&md->u.md2),
554 truncate, true);
555 proto = htons(ETH_P_ERSPAN2);
556 } else {
557 goto err_free_skb;
558 }
559
560 gre_build_header(skb, 8, TUNNEL_SEQ,
561 proto, 0, htonl(tunnel->o_seqno++));
562
563 ip_md_tunnel_xmit(skb, dev, IPPROTO_GRE, tunnel_hlen);
564
565 return;
566
567 err_free_skb:
568 kfree_skb(skb);
569 dev->stats.tx_dropped++;
570 }
571
572 static int gre_fill_metadata_dst(struct net_device *dev, struct sk_buff *skb)
573 {
574 struct ip_tunnel_info *info = skb_tunnel_info(skb);
575 const struct ip_tunnel_key *key;
576 struct rtable *rt;
577 struct flowi4 fl4;
578
579 if (ip_tunnel_info_af(info) != AF_INET)
580 return -EINVAL;
581
582 key = &info->key;
583 ip_tunnel_init_flow(&fl4, IPPROTO_GRE, key->u.ipv4.dst, key->u.ipv4.src,
584 tunnel_id_to_key32(key->tun_id), key->tos, 0,
585 skb->mark, skb_get_hash(skb));
586 rt = ip_route_output_key(dev_net(dev), &fl4);
587 if (IS_ERR(rt))
588 return PTR_ERR(rt);
589
590 ip_rt_put(rt);
591 info->key.u.ipv4.src = fl4.saddr;
592 return 0;
593 }
594
595 static netdev_tx_t ipgre_xmit(struct sk_buff *skb,
596 struct net_device *dev)
597 {
598 struct ip_tunnel *tunnel = netdev_priv(dev);
599 const struct iphdr *tnl_params;
600
601 if (!pskb_inet_may_pull(skb))
602 goto free_skb;
603
604 if (tunnel->collect_md) {
605 gre_fb_xmit(skb, dev, skb->protocol);
606 return NETDEV_TX_OK;
607 }
608
609 if (dev->header_ops) {
610 /* Need space for new headers */
611 if (skb_cow_head(skb, dev->needed_headroom -
612 (tunnel->hlen + sizeof(struct iphdr))))
613 goto free_skb;
614
615 tnl_params = (const struct iphdr *)skb->data;
616
617 /* Pull skb since ip_tunnel_xmit() needs skb->data pointing
618 * to gre header.
619 */
620 skb_pull(skb, tunnel->hlen + sizeof(struct iphdr));
621 skb_reset_mac_header(skb);
622 } else {
623 if (skb_cow_head(skb, dev->needed_headroom))
624 goto free_skb;
625
626 tnl_params = &tunnel->parms.iph;
627 }
628
629 if (gre_handle_offloads(skb, !!(tunnel->parms.o_flags & TUNNEL_CSUM)))
630 goto free_skb;
631
632 __gre_xmit(skb, dev, tnl_params, skb->protocol);
633 return NETDEV_TX_OK;
634
635 free_skb:
636 kfree_skb(skb);
637 dev->stats.tx_dropped++;
638 return NETDEV_TX_OK;
639 }
640
641 static netdev_tx_t erspan_xmit(struct sk_buff *skb,
642 struct net_device *dev)
643 {
644 struct ip_tunnel *tunnel = netdev_priv(dev);
645 bool truncate = false;
646 __be16 proto;
647
648 if (!pskb_inet_may_pull(skb))
649 goto free_skb;
650
651 if (tunnel->collect_md) {
652 erspan_fb_xmit(skb, dev);
653 return NETDEV_TX_OK;
654 }
655
656 if (gre_handle_offloads(skb, false))
657 goto free_skb;
658
659 if (skb_cow_head(skb, dev->needed_headroom))
660 goto free_skb;
661
662 if (skb->len > dev->mtu + dev->hard_header_len) {
663 pskb_trim(skb, dev->mtu + dev->hard_header_len);
664 truncate = true;
665 }
666
667 /* Push ERSPAN header */
668 if (tunnel->erspan_ver == 1) {
669 erspan_build_header(skb, ntohl(tunnel->parms.o_key),
670 tunnel->index,
671 truncate, true);
672 proto = htons(ETH_P_ERSPAN);
673 } else if (tunnel->erspan_ver == 2) {
674 erspan_build_header_v2(skb, ntohl(tunnel->parms.o_key),
675 tunnel->dir, tunnel->hwid,
676 truncate, true);
677 proto = htons(ETH_P_ERSPAN2);
678 } else {
679 goto free_skb;
680 }
681
682 tunnel->parms.o_flags &= ~TUNNEL_KEY;
683 __gre_xmit(skb, dev, &tunnel->parms.iph, proto);
684 return NETDEV_TX_OK;
685
686 free_skb:
687 kfree_skb(skb);
688 dev->stats.tx_dropped++;
689 return NETDEV_TX_OK;
690 }
691
692 static netdev_tx_t gre_tap_xmit(struct sk_buff *skb,
693 struct net_device *dev)
694 {
695 struct ip_tunnel *tunnel = netdev_priv(dev);
696
697 if (!pskb_inet_may_pull(skb))
698 goto free_skb;
699
700 if (tunnel->collect_md) {
701 gre_fb_xmit(skb, dev, htons(ETH_P_TEB));
702 return NETDEV_TX_OK;
703 }
704
705 if (gre_handle_offloads(skb, !!(tunnel->parms.o_flags & TUNNEL_CSUM)))
706 goto free_skb;
707
708 if (skb_cow_head(skb, dev->needed_headroom))
709 goto free_skb;
710
711 __gre_xmit(skb, dev, &tunnel->parms.iph, htons(ETH_P_TEB));
712 return NETDEV_TX_OK;
713
714 free_skb:
715 kfree_skb(skb);
716 dev->stats.tx_dropped++;
717 return NETDEV_TX_OK;
718 }
719
720 static void ipgre_link_update(struct net_device *dev, bool set_mtu)
721 {
722 struct ip_tunnel *tunnel = netdev_priv(dev);
723 int len;
724
725 len = tunnel->tun_hlen;
726 tunnel->tun_hlen = gre_calc_hlen(tunnel->parms.o_flags);
727 len = tunnel->tun_hlen - len;
728 tunnel->hlen = tunnel->hlen + len;
729
730 dev->needed_headroom = dev->needed_headroom + len;
731 if (set_mtu)
732 dev->mtu = max_t(int, dev->mtu - len, 68);
733
734 if (!(tunnel->parms.o_flags & TUNNEL_SEQ)) {
735 if (!(tunnel->parms.o_flags & TUNNEL_CSUM) ||
736 tunnel->encap.type == TUNNEL_ENCAP_NONE) {
737 dev->features |= NETIF_F_GSO_SOFTWARE;
738 dev->hw_features |= NETIF_F_GSO_SOFTWARE;
739 } else {
740 dev->features &= ~NETIF_F_GSO_SOFTWARE;
741 dev->hw_features &= ~NETIF_F_GSO_SOFTWARE;
742 }
743 dev->features |= NETIF_F_LLTX;
744 } else {
745 dev->hw_features &= ~NETIF_F_GSO_SOFTWARE;
746 dev->features &= ~(NETIF_F_LLTX | NETIF_F_GSO_SOFTWARE);
747 }
748 }
749
750 static int ipgre_tunnel_ioctl(struct net_device *dev,
751 struct ifreq *ifr, int cmd)
752 {
753 struct ip_tunnel_parm p;
754 int err;
755
756 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
757 return -EFAULT;
758
759 if (cmd == SIOCADDTUNNEL || cmd == SIOCCHGTUNNEL) {
760 if (p.iph.version != 4 || p.iph.protocol != IPPROTO_GRE ||
761 p.iph.ihl != 5 || (p.iph.frag_off & htons(~IP_DF)) ||
762 ((p.i_flags | p.o_flags) & (GRE_VERSION | GRE_ROUTING)))
763 return -EINVAL;
764 }
765
766 p.i_flags = gre_flags_to_tnl_flags(p.i_flags);
767 p.o_flags = gre_flags_to_tnl_flags(p.o_flags);
768
769 err = ip_tunnel_ioctl(dev, &p, cmd);
770 if (err)
771 return err;
772
773 if (cmd == SIOCCHGTUNNEL) {
774 struct ip_tunnel *t = netdev_priv(dev);
775
776 t->parms.i_flags = p.i_flags;
777 t->parms.o_flags = p.o_flags;
778
779 if (strcmp(dev->rtnl_link_ops->kind, "erspan"))
780 ipgre_link_update(dev, true);
781 }
782
783 p.i_flags = gre_tnl_flags_to_gre_flags(p.i_flags);
784 p.o_flags = gre_tnl_flags_to_gre_flags(p.o_flags);
785
786 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
787 return -EFAULT;
788
789 return 0;
790 }
791
792 /* Nice toy. Unfortunately, useless in real life :-)
793 It allows to construct virtual multiprotocol broadcast "LAN"
794 over the Internet, provided multicast routing is tuned.
795
796
797 I have no idea was this bicycle invented before me,
798 so that I had to set ARPHRD_IPGRE to a random value.
799 I have an impression, that Cisco could make something similar,
800 but this feature is apparently missing in IOS<=11.2(8).
801
802 I set up 10.66.66/24 and fec0:6666:6666::0/96 as virtual networks
803 with broadcast 224.66.66.66. If you have access to mbone, play with me :-)
804
805 ping -t 255 224.66.66.66
806
807 If nobody answers, mbone does not work.
808
809 ip tunnel add Universe mode gre remote 224.66.66.66 local <Your_real_addr> ttl 255
810 ip addr add 10.66.66.<somewhat>/24 dev Universe
811 ifconfig Universe up
812 ifconfig Universe add fe80::<Your_real_addr>/10
813 ifconfig Universe add fec0:6666:6666::<Your_real_addr>/96
814 ftp 10.66.66.66
815 ...
816 ftp fec0:6666:6666::193.233.7.65
817 ...
818 */
819 static int ipgre_header(struct sk_buff *skb, struct net_device *dev,
820 unsigned short type,
821 const void *daddr, const void *saddr, unsigned int len)
822 {
823 struct ip_tunnel *t = netdev_priv(dev);
824 struct iphdr *iph;
825 struct gre_base_hdr *greh;
826
827 iph = skb_push(skb, t->hlen + sizeof(*iph));
828 greh = (struct gre_base_hdr *)(iph+1);
829 greh->flags = gre_tnl_flags_to_gre_flags(t->parms.o_flags);
830 greh->protocol = htons(type);
831
832 memcpy(iph, &t->parms.iph, sizeof(struct iphdr));
833
834 /* Set the source hardware address. */
835 if (saddr)
836 memcpy(&iph->saddr, saddr, 4);
837 if (daddr)
838 memcpy(&iph->daddr, daddr, 4);
839 if (iph->daddr)
840 return t->hlen + sizeof(*iph);
841
842 return -(t->hlen + sizeof(*iph));
843 }
844
845 static int ipgre_header_parse(const struct sk_buff *skb, unsigned char *haddr)
846 {
847 const struct iphdr *iph = (const struct iphdr *) skb_mac_header(skb);
848 memcpy(haddr, &iph->saddr, 4);
849 return 4;
850 }
851
852 static const struct header_ops ipgre_header_ops = {
853 .create = ipgre_header,
854 .parse = ipgre_header_parse,
855 };
856
857 #ifdef CONFIG_NET_IPGRE_BROADCAST
858 static int ipgre_open(struct net_device *dev)
859 {
860 struct ip_tunnel *t = netdev_priv(dev);
861
862 if (ipv4_is_multicast(t->parms.iph.daddr)) {
863 struct flowi4 fl4;
864 struct rtable *rt;
865
866 rt = ip_route_output_gre(t->net, &fl4,
867 t->parms.iph.daddr,
868 t->parms.iph.saddr,
869 t->parms.o_key,
870 RT_TOS(t->parms.iph.tos),
871 t->parms.link);
872 if (IS_ERR(rt))
873 return -EADDRNOTAVAIL;
874 dev = rt->dst.dev;
875 ip_rt_put(rt);
876 if (!__in_dev_get_rtnl(dev))
877 return -EADDRNOTAVAIL;
878 t->mlink = dev->ifindex;
879 ip_mc_inc_group(__in_dev_get_rtnl(dev), t->parms.iph.daddr);
880 }
881 return 0;
882 }
883
884 static int ipgre_close(struct net_device *dev)
885 {
886 struct ip_tunnel *t = netdev_priv(dev);
887
888 if (ipv4_is_multicast(t->parms.iph.daddr) && t->mlink) {
889 struct in_device *in_dev;
890 in_dev = inetdev_by_index(t->net, t->mlink);
891 if (in_dev)
892 ip_mc_dec_group(in_dev, t->parms.iph.daddr);
893 }
894 return 0;
895 }
896 #endif
897
898 static const struct net_device_ops ipgre_netdev_ops = {
899 .ndo_init = ipgre_tunnel_init,
900 .ndo_uninit = ip_tunnel_uninit,
901 #ifdef CONFIG_NET_IPGRE_BROADCAST
902 .ndo_open = ipgre_open,
903 .ndo_stop = ipgre_close,
904 #endif
905 .ndo_start_xmit = ipgre_xmit,
906 .ndo_do_ioctl = ipgre_tunnel_ioctl,
907 .ndo_change_mtu = ip_tunnel_change_mtu,
908 .ndo_get_stats64 = ip_tunnel_get_stats64,
909 .ndo_get_iflink = ip_tunnel_get_iflink,
910 };
911
912 #define GRE_FEATURES (NETIF_F_SG | \
913 NETIF_F_FRAGLIST | \
914 NETIF_F_HIGHDMA | \
915 NETIF_F_HW_CSUM)
916
917 static void ipgre_tunnel_setup(struct net_device *dev)
918 {
919 dev->netdev_ops = &ipgre_netdev_ops;
920 dev->type = ARPHRD_IPGRE;
921 ip_tunnel_setup(dev, ipgre_net_id);
922 }
923
924 static void __gre_tunnel_init(struct net_device *dev)
925 {
926 struct ip_tunnel *tunnel;
927
928 tunnel = netdev_priv(dev);
929 tunnel->tun_hlen = gre_calc_hlen(tunnel->parms.o_flags);
930 tunnel->parms.iph.protocol = IPPROTO_GRE;
931
932 tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen;
933
934 dev->features |= GRE_FEATURES;
935 dev->hw_features |= GRE_FEATURES;
936
937 if (!(tunnel->parms.o_flags & TUNNEL_SEQ)) {
938 /* TCP offload with GRE SEQ is not supported, nor
939 * can we support 2 levels of outer headers requiring
940 * an update.
941 */
942 if (!(tunnel->parms.o_flags & TUNNEL_CSUM) ||
943 (tunnel->encap.type == TUNNEL_ENCAP_NONE)) {
944 dev->features |= NETIF_F_GSO_SOFTWARE;
945 dev->hw_features |= NETIF_F_GSO_SOFTWARE;
946 }
947
948 /* Can use a lockless transmit, unless we generate
949 * output sequences
950 */
951 dev->features |= NETIF_F_LLTX;
952 }
953 }
954
955 static int ipgre_tunnel_init(struct net_device *dev)
956 {
957 struct ip_tunnel *tunnel = netdev_priv(dev);
958 struct iphdr *iph = &tunnel->parms.iph;
959
960 __gre_tunnel_init(dev);
961
962 memcpy(dev->dev_addr, &iph->saddr, 4);
963 memcpy(dev->broadcast, &iph->daddr, 4);
964
965 dev->flags = IFF_NOARP;
966 netif_keep_dst(dev);
967 dev->addr_len = 4;
968
969 if (iph->daddr && !tunnel->collect_md) {
970 #ifdef CONFIG_NET_IPGRE_BROADCAST
971 if (ipv4_is_multicast(iph->daddr)) {
972 if (!iph->saddr)
973 return -EINVAL;
974 dev->flags = IFF_BROADCAST;
975 dev->header_ops = &ipgre_header_ops;
976 }
977 #endif
978 } else if (!tunnel->collect_md) {
979 dev->header_ops = &ipgre_header_ops;
980 }
981
982 return ip_tunnel_init(dev);
983 }
984
985 static const struct gre_protocol ipgre_protocol = {
986 .handler = gre_rcv,
987 .err_handler = gre_err,
988 };
989
990 static int __net_init ipgre_init_net(struct net *net)
991 {
992 return ip_tunnel_init_net(net, ipgre_net_id, &ipgre_link_ops, NULL);
993 }
994
995 static void __net_exit ipgre_exit_batch_net(struct list_head *list_net)
996 {
997 ip_tunnel_delete_nets(list_net, ipgre_net_id, &ipgre_link_ops);
998 }
999
1000 static struct pernet_operations ipgre_net_ops = {
1001 .init = ipgre_init_net,
1002 .exit_batch = ipgre_exit_batch_net,
1003 .id = &ipgre_net_id,
1004 .size = sizeof(struct ip_tunnel_net),
1005 };
1006
1007 static int ipgre_tunnel_validate(struct nlattr *tb[], struct nlattr *data[],
1008 struct netlink_ext_ack *extack)
1009 {
1010 __be16 flags;
1011
1012 if (!data)
1013 return 0;
1014
1015 flags = 0;
1016 if (data[IFLA_GRE_IFLAGS])
1017 flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]);
1018 if (data[IFLA_GRE_OFLAGS])
1019 flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]);
1020 if (flags & (GRE_VERSION|GRE_ROUTING))
1021 return -EINVAL;
1022
1023 if (data[IFLA_GRE_COLLECT_METADATA] &&
1024 data[IFLA_GRE_ENCAP_TYPE] &&
1025 nla_get_u16(data[IFLA_GRE_ENCAP_TYPE]) != TUNNEL_ENCAP_NONE)
1026 return -EINVAL;
1027
1028 return 0;
1029 }
1030
1031 static int ipgre_tap_validate(struct nlattr *tb[], struct nlattr *data[],
1032 struct netlink_ext_ack *extack)
1033 {
1034 __be32 daddr;
1035
1036 if (tb[IFLA_ADDRESS]) {
1037 if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
1038 return -EINVAL;
1039 if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
1040 return -EADDRNOTAVAIL;
1041 }
1042
1043 if (!data)
1044 goto out;
1045
1046 if (data[IFLA_GRE_REMOTE]) {
1047 memcpy(&daddr, nla_data(data[IFLA_GRE_REMOTE]), 4);
1048 if (!daddr)
1049 return -EINVAL;
1050 }
1051
1052 out:
1053 return ipgre_tunnel_validate(tb, data, extack);
1054 }
1055
1056 static int erspan_validate(struct nlattr *tb[], struct nlattr *data[],
1057 struct netlink_ext_ack *extack)
1058 {
1059 __be16 flags = 0;
1060 int ret;
1061
1062 if (!data)
1063 return 0;
1064
1065 ret = ipgre_tap_validate(tb, data, extack);
1066 if (ret)
1067 return ret;
1068
1069 /* ERSPAN should only have GRE sequence and key flag */
1070 if (data[IFLA_GRE_OFLAGS])
1071 flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]);
1072 if (data[IFLA_GRE_IFLAGS])
1073 flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]);
1074 if (!data[IFLA_GRE_COLLECT_METADATA] &&
1075 flags != (GRE_SEQ | GRE_KEY))
1076 return -EINVAL;
1077
1078 /* ERSPAN Session ID only has 10-bit. Since we reuse
1079 * 32-bit key field as ID, check it's range.
1080 */
1081 if (data[IFLA_GRE_IKEY] &&
1082 (ntohl(nla_get_be32(data[IFLA_GRE_IKEY])) & ~ID_MASK))
1083 return -EINVAL;
1084
1085 if (data[IFLA_GRE_OKEY] &&
1086 (ntohl(nla_get_be32(data[IFLA_GRE_OKEY])) & ~ID_MASK))
1087 return -EINVAL;
1088
1089 return 0;
1090 }
1091
1092 static int ipgre_netlink_parms(struct net_device *dev,
1093 struct nlattr *data[],
1094 struct nlattr *tb[],
1095 struct ip_tunnel_parm *parms,
1096 __u32 *fwmark)
1097 {
1098 struct ip_tunnel *t = netdev_priv(dev);
1099
1100 memset(parms, 0, sizeof(*parms));
1101
1102 parms->iph.protocol = IPPROTO_GRE;
1103
1104 if (!data)
1105 return 0;
1106
1107 if (data[IFLA_GRE_LINK])
1108 parms->link = nla_get_u32(data[IFLA_GRE_LINK]);
1109
1110 if (data[IFLA_GRE_IFLAGS])
1111 parms->i_flags = gre_flags_to_tnl_flags(nla_get_be16(data[IFLA_GRE_IFLAGS]));
1112
1113 if (data[IFLA_GRE_OFLAGS])
1114 parms->o_flags = gre_flags_to_tnl_flags(nla_get_be16(data[IFLA_GRE_OFLAGS]));
1115
1116 if (data[IFLA_GRE_IKEY])
1117 parms->i_key = nla_get_be32(data[IFLA_GRE_IKEY]);
1118
1119 if (data[IFLA_GRE_OKEY])
1120 parms->o_key = nla_get_be32(data[IFLA_GRE_OKEY]);
1121
1122 if (data[IFLA_GRE_LOCAL])
1123 parms->iph.saddr = nla_get_in_addr(data[IFLA_GRE_LOCAL]);
1124
1125 if (data[IFLA_GRE_REMOTE])
1126 parms->iph.daddr = nla_get_in_addr(data[IFLA_GRE_REMOTE]);
1127
1128 if (data[IFLA_GRE_TTL])
1129 parms->iph.ttl = nla_get_u8(data[IFLA_GRE_TTL]);
1130
1131 if (data[IFLA_GRE_TOS])
1132 parms->iph.tos = nla_get_u8(data[IFLA_GRE_TOS]);
1133
1134 if (!data[IFLA_GRE_PMTUDISC] || nla_get_u8(data[IFLA_GRE_PMTUDISC])) {
1135 if (t->ignore_df)
1136 return -EINVAL;
1137 parms->iph.frag_off = htons(IP_DF);
1138 }
1139
1140 if (data[IFLA_GRE_COLLECT_METADATA]) {
1141 t->collect_md = true;
1142 if (dev->type == ARPHRD_IPGRE)
1143 dev->type = ARPHRD_NONE;
1144 }
1145
1146 if (data[IFLA_GRE_IGNORE_DF]) {
1147 if (nla_get_u8(data[IFLA_GRE_IGNORE_DF])
1148 && (parms->iph.frag_off & htons(IP_DF)))
1149 return -EINVAL;
1150 t->ignore_df = !!nla_get_u8(data[IFLA_GRE_IGNORE_DF]);
1151 }
1152
1153 if (data[IFLA_GRE_FWMARK])
1154 *fwmark = nla_get_u32(data[IFLA_GRE_FWMARK]);
1155
1156 return 0;
1157 }
1158
1159 static int erspan_netlink_parms(struct net_device *dev,
1160 struct nlattr *data[],
1161 struct nlattr *tb[],
1162 struct ip_tunnel_parm *parms,
1163 __u32 *fwmark)
1164 {
1165 struct ip_tunnel *t = netdev_priv(dev);
1166 int err;
1167
1168 err = ipgre_netlink_parms(dev, data, tb, parms, fwmark);
1169 if (err)
1170 return err;
1171 if (!data)
1172 return 0;
1173
1174 if (data[IFLA_GRE_ERSPAN_VER]) {
1175 t->erspan_ver = nla_get_u8(data[IFLA_GRE_ERSPAN_VER]);
1176
1177 if (t->erspan_ver != 1 && t->erspan_ver != 2)
1178 return -EINVAL;
1179 }
1180
1181 if (t->erspan_ver == 1) {
1182 if (data[IFLA_GRE_ERSPAN_INDEX]) {
1183 t->index = nla_get_u32(data[IFLA_GRE_ERSPAN_INDEX]);
1184 if (t->index & ~INDEX_MASK)
1185 return -EINVAL;
1186 }
1187 } else if (t->erspan_ver == 2) {
1188 if (data[IFLA_GRE_ERSPAN_DIR]) {
1189 t->dir = nla_get_u8(data[IFLA_GRE_ERSPAN_DIR]);
1190 if (t->dir & ~(DIR_MASK >> DIR_OFFSET))
1191 return -EINVAL;
1192 }
1193 if (data[IFLA_GRE_ERSPAN_HWID]) {
1194 t->hwid = nla_get_u16(data[IFLA_GRE_ERSPAN_HWID]);
1195 if (t->hwid & ~(HWID_MASK >> HWID_OFFSET))
1196 return -EINVAL;
1197 }
1198 }
1199
1200 return 0;
1201 }
1202
1203 /* This function returns true when ENCAP attributes are present in the nl msg */
1204 static bool ipgre_netlink_encap_parms(struct nlattr *data[],
1205 struct ip_tunnel_encap *ipencap)
1206 {
1207 bool ret = false;
1208
1209 memset(ipencap, 0, sizeof(*ipencap));
1210
1211 if (!data)
1212 return ret;
1213
1214 if (data[IFLA_GRE_ENCAP_TYPE]) {
1215 ret = true;
1216 ipencap->type = nla_get_u16(data[IFLA_GRE_ENCAP_TYPE]);
1217 }
1218
1219 if (data[IFLA_GRE_ENCAP_FLAGS]) {
1220 ret = true;
1221 ipencap->flags = nla_get_u16(data[IFLA_GRE_ENCAP_FLAGS]);
1222 }
1223
1224 if (data[IFLA_GRE_ENCAP_SPORT]) {
1225 ret = true;
1226 ipencap->sport = nla_get_be16(data[IFLA_GRE_ENCAP_SPORT]);
1227 }
1228
1229 if (data[IFLA_GRE_ENCAP_DPORT]) {
1230 ret = true;
1231 ipencap->dport = nla_get_be16(data[IFLA_GRE_ENCAP_DPORT]);
1232 }
1233
1234 return ret;
1235 }
1236
1237 static int gre_tap_init(struct net_device *dev)
1238 {
1239 __gre_tunnel_init(dev);
1240 dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1241 netif_keep_dst(dev);
1242
1243 return ip_tunnel_init(dev);
1244 }
1245
1246 static const struct net_device_ops gre_tap_netdev_ops = {
1247 .ndo_init = gre_tap_init,
1248 .ndo_uninit = ip_tunnel_uninit,
1249 .ndo_start_xmit = gre_tap_xmit,
1250 .ndo_set_mac_address = eth_mac_addr,
1251 .ndo_validate_addr = eth_validate_addr,
1252 .ndo_change_mtu = ip_tunnel_change_mtu,
1253 .ndo_get_stats64 = ip_tunnel_get_stats64,
1254 .ndo_get_iflink = ip_tunnel_get_iflink,
1255 .ndo_fill_metadata_dst = gre_fill_metadata_dst,
1256 };
1257
1258 static int erspan_tunnel_init(struct net_device *dev)
1259 {
1260 struct ip_tunnel *tunnel = netdev_priv(dev);
1261
1262 tunnel->tun_hlen = 8;
1263 tunnel->parms.iph.protocol = IPPROTO_GRE;
1264 tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen +
1265 erspan_hdr_len(tunnel->erspan_ver);
1266
1267 dev->features |= GRE_FEATURES;
1268 dev->hw_features |= GRE_FEATURES;
1269 dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1270 netif_keep_dst(dev);
1271
1272 return ip_tunnel_init(dev);
1273 }
1274
1275 static const struct net_device_ops erspan_netdev_ops = {
1276 .ndo_init = erspan_tunnel_init,
1277 .ndo_uninit = ip_tunnel_uninit,
1278 .ndo_start_xmit = erspan_xmit,
1279 .ndo_set_mac_address = eth_mac_addr,
1280 .ndo_validate_addr = eth_validate_addr,
1281 .ndo_change_mtu = ip_tunnel_change_mtu,
1282 .ndo_get_stats64 = ip_tunnel_get_stats64,
1283 .ndo_get_iflink = ip_tunnel_get_iflink,
1284 .ndo_fill_metadata_dst = gre_fill_metadata_dst,
1285 };
1286
1287 static void ipgre_tap_setup(struct net_device *dev)
1288 {
1289 ether_setup(dev);
1290 dev->max_mtu = 0;
1291 dev->netdev_ops = &gre_tap_netdev_ops;
1292 dev->priv_flags &= ~IFF_TX_SKB_SHARING;
1293 dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1294 ip_tunnel_setup(dev, gre_tap_net_id);
1295 }
1296
1297 static int
1298 ipgre_newlink_encap_setup(struct net_device *dev, struct nlattr *data[])
1299 {
1300 struct ip_tunnel_encap ipencap;
1301
1302 if (ipgre_netlink_encap_parms(data, &ipencap)) {
1303 struct ip_tunnel *t = netdev_priv(dev);
1304 int err = ip_tunnel_encap_setup(t, &ipencap);
1305
1306 if (err < 0)
1307 return err;
1308 }
1309
1310 return 0;
1311 }
1312
1313 static int ipgre_newlink(struct net *src_net, struct net_device *dev,
1314 struct nlattr *tb[], struct nlattr *data[],
1315 struct netlink_ext_ack *extack)
1316 {
1317 struct ip_tunnel_parm p;
1318 __u32 fwmark = 0;
1319 int err;
1320
1321 err = ipgre_newlink_encap_setup(dev, data);
1322 if (err)
1323 return err;
1324
1325 err = ipgre_netlink_parms(dev, data, tb, &p, &fwmark);
1326 if (err < 0)
1327 return err;
1328 return ip_tunnel_newlink(dev, tb, &p, fwmark);
1329 }
1330
1331 static int erspan_newlink(struct net *src_net, struct net_device *dev,
1332 struct nlattr *tb[], struct nlattr *data[],
1333 struct netlink_ext_ack *extack)
1334 {
1335 struct ip_tunnel_parm p;
1336 __u32 fwmark = 0;
1337 int err;
1338
1339 err = ipgre_newlink_encap_setup(dev, data);
1340 if (err)
1341 return err;
1342
1343 err = erspan_netlink_parms(dev, data, tb, &p, &fwmark);
1344 if (err)
1345 return err;
1346 return ip_tunnel_newlink(dev, tb, &p, fwmark);
1347 }
1348
1349 static int ipgre_changelink(struct net_device *dev, struct nlattr *tb[],
1350 struct nlattr *data[],
1351 struct netlink_ext_ack *extack)
1352 {
1353 struct ip_tunnel *t = netdev_priv(dev);
1354 __u32 fwmark = t->fwmark;
1355 struct ip_tunnel_parm p;
1356 int err;
1357
1358 err = ipgre_newlink_encap_setup(dev, data);
1359 if (err)
1360 return err;
1361
1362 err = ipgre_netlink_parms(dev, data, tb, &p, &fwmark);
1363 if (err < 0)
1364 return err;
1365
1366 err = ip_tunnel_changelink(dev, tb, &p, fwmark);
1367 if (err < 0)
1368 return err;
1369
1370 t->parms.i_flags = p.i_flags;
1371 t->parms.o_flags = p.o_flags;
1372
1373 ipgre_link_update(dev, !tb[IFLA_MTU]);
1374
1375 return 0;
1376 }
1377
1378 static int erspan_changelink(struct net_device *dev, struct nlattr *tb[],
1379 struct nlattr *data[],
1380 struct netlink_ext_ack *extack)
1381 {
1382 struct ip_tunnel *t = netdev_priv(dev);
1383 __u32 fwmark = t->fwmark;
1384 struct ip_tunnel_parm p;
1385 int err;
1386
1387 err = ipgre_newlink_encap_setup(dev, data);
1388 if (err)
1389 return err;
1390
1391 err = erspan_netlink_parms(dev, data, tb, &p, &fwmark);
1392 if (err < 0)
1393 return err;
1394
1395 err = ip_tunnel_changelink(dev, tb, &p, fwmark);
1396 if (err < 0)
1397 return err;
1398
1399 t->parms.i_flags = p.i_flags;
1400 t->parms.o_flags = p.o_flags;
1401
1402 return 0;
1403 }
1404
1405 static size_t ipgre_get_size(const struct net_device *dev)
1406 {
1407 return
1408 /* IFLA_GRE_LINK */
1409 nla_total_size(4) +
1410 /* IFLA_GRE_IFLAGS */
1411 nla_total_size(2) +
1412 /* IFLA_GRE_OFLAGS */
1413 nla_total_size(2) +
1414 /* IFLA_GRE_IKEY */
1415 nla_total_size(4) +
1416 /* IFLA_GRE_OKEY */
1417 nla_total_size(4) +
1418 /* IFLA_GRE_LOCAL */
1419 nla_total_size(4) +
1420 /* IFLA_GRE_REMOTE */
1421 nla_total_size(4) +
1422 /* IFLA_GRE_TTL */
1423 nla_total_size(1) +
1424 /* IFLA_GRE_TOS */
1425 nla_total_size(1) +
1426 /* IFLA_GRE_PMTUDISC */
1427 nla_total_size(1) +
1428 /* IFLA_GRE_ENCAP_TYPE */
1429 nla_total_size(2) +
1430 /* IFLA_GRE_ENCAP_FLAGS */
1431 nla_total_size(2) +
1432 /* IFLA_GRE_ENCAP_SPORT */
1433 nla_total_size(2) +
1434 /* IFLA_GRE_ENCAP_DPORT */
1435 nla_total_size(2) +
1436 /* IFLA_GRE_COLLECT_METADATA */
1437 nla_total_size(0) +
1438 /* IFLA_GRE_IGNORE_DF */
1439 nla_total_size(1) +
1440 /* IFLA_GRE_FWMARK */
1441 nla_total_size(4) +
1442 /* IFLA_GRE_ERSPAN_INDEX */
1443 nla_total_size(4) +
1444 /* IFLA_GRE_ERSPAN_VER */
1445 nla_total_size(1) +
1446 /* IFLA_GRE_ERSPAN_DIR */
1447 nla_total_size(1) +
1448 /* IFLA_GRE_ERSPAN_HWID */
1449 nla_total_size(2) +
1450 0;
1451 }
1452
1453 static int ipgre_fill_info(struct sk_buff *skb, const struct net_device *dev)
1454 {
1455 struct ip_tunnel *t = netdev_priv(dev);
1456 struct ip_tunnel_parm *p = &t->parms;
1457 __be16 o_flags = p->o_flags;
1458
1459 if (t->erspan_ver == 1 || t->erspan_ver == 2) {
1460 if (!t->collect_md)
1461 o_flags |= TUNNEL_KEY;
1462
1463 if (nla_put_u8(skb, IFLA_GRE_ERSPAN_VER, t->erspan_ver))
1464 goto nla_put_failure;
1465
1466 if (t->erspan_ver == 1) {
1467 if (nla_put_u32(skb, IFLA_GRE_ERSPAN_INDEX, t->index))
1468 goto nla_put_failure;
1469 } else {
1470 if (nla_put_u8(skb, IFLA_GRE_ERSPAN_DIR, t->dir))
1471 goto nla_put_failure;
1472 if (nla_put_u16(skb, IFLA_GRE_ERSPAN_HWID, t->hwid))
1473 goto nla_put_failure;
1474 }
1475 }
1476
1477 if (nla_put_u32(skb, IFLA_GRE_LINK, p->link) ||
1478 nla_put_be16(skb, IFLA_GRE_IFLAGS,
1479 gre_tnl_flags_to_gre_flags(p->i_flags)) ||
1480 nla_put_be16(skb, IFLA_GRE_OFLAGS,
1481 gre_tnl_flags_to_gre_flags(o_flags)) ||
1482 nla_put_be32(skb, IFLA_GRE_IKEY, p->i_key) ||
1483 nla_put_be32(skb, IFLA_GRE_OKEY, p->o_key) ||
1484 nla_put_in_addr(skb, IFLA_GRE_LOCAL, p->iph.saddr) ||
1485 nla_put_in_addr(skb, IFLA_GRE_REMOTE, p->iph.daddr) ||
1486 nla_put_u8(skb, IFLA_GRE_TTL, p->iph.ttl) ||
1487 nla_put_u8(skb, IFLA_GRE_TOS, p->iph.tos) ||
1488 nla_put_u8(skb, IFLA_GRE_PMTUDISC,
1489 !!(p->iph.frag_off & htons(IP_DF))) ||
1490 nla_put_u32(skb, IFLA_GRE_FWMARK, t->fwmark))
1491 goto nla_put_failure;
1492
1493 if (nla_put_u16(skb, IFLA_GRE_ENCAP_TYPE,
1494 t->encap.type) ||
1495 nla_put_be16(skb, IFLA_GRE_ENCAP_SPORT,
1496 t->encap.sport) ||
1497 nla_put_be16(skb, IFLA_GRE_ENCAP_DPORT,
1498 t->encap.dport) ||
1499 nla_put_u16(skb, IFLA_GRE_ENCAP_FLAGS,
1500 t->encap.flags))
1501 goto nla_put_failure;
1502
1503 if (nla_put_u8(skb, IFLA_GRE_IGNORE_DF, t->ignore_df))
1504 goto nla_put_failure;
1505
1506 if (t->collect_md) {
1507 if (nla_put_flag(skb, IFLA_GRE_COLLECT_METADATA))
1508 goto nla_put_failure;
1509 }
1510
1511 return 0;
1512
1513 nla_put_failure:
1514 return -EMSGSIZE;
1515 }
1516
1517 static void erspan_setup(struct net_device *dev)
1518 {
1519 struct ip_tunnel *t = netdev_priv(dev);
1520
1521 ether_setup(dev);
1522 dev->max_mtu = 0;
1523 dev->netdev_ops = &erspan_netdev_ops;
1524 dev->priv_flags &= ~IFF_TX_SKB_SHARING;
1525 dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1526 ip_tunnel_setup(dev, erspan_net_id);
1527 t->erspan_ver = 1;
1528 }
1529
1530 static const struct nla_policy ipgre_policy[IFLA_GRE_MAX + 1] = {
1531 [IFLA_GRE_LINK] = { .type = NLA_U32 },
1532 [IFLA_GRE_IFLAGS] = { .type = NLA_U16 },
1533 [IFLA_GRE_OFLAGS] = { .type = NLA_U16 },
1534 [IFLA_GRE_IKEY] = { .type = NLA_U32 },
1535 [IFLA_GRE_OKEY] = { .type = NLA_U32 },
1536 [IFLA_GRE_LOCAL] = { .len = sizeof_field(struct iphdr, saddr) },
1537 [IFLA_GRE_REMOTE] = { .len = sizeof_field(struct iphdr, daddr) },
1538 [IFLA_GRE_TTL] = { .type = NLA_U8 },
1539 [IFLA_GRE_TOS] = { .type = NLA_U8 },
1540 [IFLA_GRE_PMTUDISC] = { .type = NLA_U8 },
1541 [IFLA_GRE_ENCAP_TYPE] = { .type = NLA_U16 },
1542 [IFLA_GRE_ENCAP_FLAGS] = { .type = NLA_U16 },
1543 [IFLA_GRE_ENCAP_SPORT] = { .type = NLA_U16 },
1544 [IFLA_GRE_ENCAP_DPORT] = { .type = NLA_U16 },
1545 [IFLA_GRE_COLLECT_METADATA] = { .type = NLA_FLAG },
1546 [IFLA_GRE_IGNORE_DF] = { .type = NLA_U8 },
1547 [IFLA_GRE_FWMARK] = { .type = NLA_U32 },
1548 [IFLA_GRE_ERSPAN_INDEX] = { .type = NLA_U32 },
1549 [IFLA_GRE_ERSPAN_VER] = { .type = NLA_U8 },
1550 [IFLA_GRE_ERSPAN_DIR] = { .type = NLA_U8 },
1551 [IFLA_GRE_ERSPAN_HWID] = { .type = NLA_U16 },
1552 };
1553
1554 static struct rtnl_link_ops ipgre_link_ops __read_mostly = {
1555 .kind = "gre",
1556 .maxtype = IFLA_GRE_MAX,
1557 .policy = ipgre_policy,
1558 .priv_size = sizeof(struct ip_tunnel),
1559 .setup = ipgre_tunnel_setup,
1560 .validate = ipgre_tunnel_validate,
1561 .newlink = ipgre_newlink,
1562 .changelink = ipgre_changelink,
1563 .dellink = ip_tunnel_dellink,
1564 .get_size = ipgre_get_size,
1565 .fill_info = ipgre_fill_info,
1566 .get_link_net = ip_tunnel_get_link_net,
1567 };
1568
1569 static struct rtnl_link_ops ipgre_tap_ops __read_mostly = {
1570 .kind = "gretap",
1571 .maxtype = IFLA_GRE_MAX,
1572 .policy = ipgre_policy,
1573 .priv_size = sizeof(struct ip_tunnel),
1574 .setup = ipgre_tap_setup,
1575 .validate = ipgre_tap_validate,
1576 .newlink = ipgre_newlink,
1577 .changelink = ipgre_changelink,
1578 .dellink = ip_tunnel_dellink,
1579 .get_size = ipgre_get_size,
1580 .fill_info = ipgre_fill_info,
1581 .get_link_net = ip_tunnel_get_link_net,
1582 };
1583
1584 static struct rtnl_link_ops erspan_link_ops __read_mostly = {
1585 .kind = "erspan",
1586 .maxtype = IFLA_GRE_MAX,
1587 .policy = ipgre_policy,
1588 .priv_size = sizeof(struct ip_tunnel),
1589 .setup = erspan_setup,
1590 .validate = erspan_validate,
1591 .newlink = erspan_newlink,
1592 .changelink = erspan_changelink,
1593 .dellink = ip_tunnel_dellink,
1594 .get_size = ipgre_get_size,
1595 .fill_info = ipgre_fill_info,
1596 .get_link_net = ip_tunnel_get_link_net,
1597 };
1598
1599 struct net_device *gretap_fb_dev_create(struct net *net, const char *name,
1600 u8 name_assign_type)
1601 {
1602 struct nlattr *tb[IFLA_MAX + 1];
1603 struct net_device *dev;
1604 LIST_HEAD(list_kill);
1605 struct ip_tunnel *t;
1606 int err;
1607
1608 memset(&tb, 0, sizeof(tb));
1609
1610 dev = rtnl_create_link(net, name, name_assign_type,
1611 &ipgre_tap_ops, tb, NULL);
1612 if (IS_ERR(dev))
1613 return dev;
1614
1615 /* Configure flow based GRE device. */
1616 t = netdev_priv(dev);
1617 t->collect_md = true;
1618
1619 err = ipgre_newlink(net, dev, tb, NULL, NULL);
1620 if (err < 0) {
1621 free_netdev(dev);
1622 return ERR_PTR(err);
1623 }
1624
1625 /* openvswitch users expect packet sizes to be unrestricted,
1626 * so set the largest MTU we can.
1627 */
1628 err = __ip_tunnel_change_mtu(dev, IP_MAX_MTU, false);
1629 if (err)
1630 goto out;
1631
1632 err = rtnl_configure_link(dev, NULL);
1633 if (err < 0)
1634 goto out;
1635
1636 return dev;
1637 out:
1638 ip_tunnel_dellink(dev, &list_kill);
1639 unregister_netdevice_many(&list_kill);
1640 return ERR_PTR(err);
1641 }
1642 EXPORT_SYMBOL_GPL(gretap_fb_dev_create);
1643
1644 static int __net_init ipgre_tap_init_net(struct net *net)
1645 {
1646 return ip_tunnel_init_net(net, gre_tap_net_id, &ipgre_tap_ops, "gretap0");
1647 }
1648
1649 static void __net_exit ipgre_tap_exit_batch_net(struct list_head *list_net)
1650 {
1651 ip_tunnel_delete_nets(list_net, gre_tap_net_id, &ipgre_tap_ops);
1652 }
1653
1654 static struct pernet_operations ipgre_tap_net_ops = {
1655 .init = ipgre_tap_init_net,
1656 .exit_batch = ipgre_tap_exit_batch_net,
1657 .id = &gre_tap_net_id,
1658 .size = sizeof(struct ip_tunnel_net),
1659 };
1660
1661 static int __net_init erspan_init_net(struct net *net)
1662 {
1663 return ip_tunnel_init_net(net, erspan_net_id,
1664 &erspan_link_ops, "erspan0");
1665 }
1666
1667 static void __net_exit erspan_exit_batch_net(struct list_head *net_list)
1668 {
1669 ip_tunnel_delete_nets(net_list, erspan_net_id, &erspan_link_ops);
1670 }
1671
1672 static struct pernet_operations erspan_net_ops = {
1673 .init = erspan_init_net,
1674 .exit_batch = erspan_exit_batch_net,
1675 .id = &erspan_net_id,
1676 .size = sizeof(struct ip_tunnel_net),
1677 };
1678
1679 static int __init ipgre_init(void)
1680 {
1681 int err;
1682
1683 pr_info("GRE over IPv4 tunneling driver\n");
1684
1685 err = register_pernet_device(&ipgre_net_ops);
1686 if (err < 0)
1687 return err;
1688
1689 err = register_pernet_device(&ipgre_tap_net_ops);
1690 if (err < 0)
1691 goto pnet_tap_failed;
1692
1693 err = register_pernet_device(&erspan_net_ops);
1694 if (err < 0)
1695 goto pnet_erspan_failed;
1696
1697 err = gre_add_protocol(&ipgre_protocol, GREPROTO_CISCO);
1698 if (err < 0) {
1699 pr_info("%s: can't add protocol\n", __func__);
1700 goto add_proto_failed;
1701 }
1702
1703 err = rtnl_link_register(&ipgre_link_ops);
1704 if (err < 0)
1705 goto rtnl_link_failed;
1706
1707 err = rtnl_link_register(&ipgre_tap_ops);
1708 if (err < 0)
1709 goto tap_ops_failed;
1710
1711 err = rtnl_link_register(&erspan_link_ops);
1712 if (err < 0)
1713 goto erspan_link_failed;
1714
1715 return 0;
1716
1717 erspan_link_failed:
1718 rtnl_link_unregister(&ipgre_tap_ops);
1719 tap_ops_failed:
1720 rtnl_link_unregister(&ipgre_link_ops);
1721 rtnl_link_failed:
1722 gre_del_protocol(&ipgre_protocol, GREPROTO_CISCO);
1723 add_proto_failed:
1724 unregister_pernet_device(&erspan_net_ops);
1725 pnet_erspan_failed:
1726 unregister_pernet_device(&ipgre_tap_net_ops);
1727 pnet_tap_failed:
1728 unregister_pernet_device(&ipgre_net_ops);
1729 return err;
1730 }
1731
1732 static void __exit ipgre_fini(void)
1733 {
1734 rtnl_link_unregister(&ipgre_tap_ops);
1735 rtnl_link_unregister(&ipgre_link_ops);
1736 rtnl_link_unregister(&erspan_link_ops);
1737 gre_del_protocol(&ipgre_protocol, GREPROTO_CISCO);
1738 unregister_pernet_device(&ipgre_tap_net_ops);
1739 unregister_pernet_device(&ipgre_net_ops);
1740 unregister_pernet_device(&erspan_net_ops);
1741 }
1742
1743 module_init(ipgre_init);
1744 module_exit(ipgre_fini);
1745 MODULE_LICENSE("GPL");
1746 MODULE_ALIAS_RTNL_LINK("gre");
1747 MODULE_ALIAS_RTNL_LINK("gretap");
1748 MODULE_ALIAS_RTNL_LINK("erspan");
1749 MODULE_ALIAS_NETDEV("gre0");
1750 MODULE_ALIAS_NETDEV("gretap0");
1751 MODULE_ALIAS_NETDEV("erspan0");
Linux with added FPC-III support