1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Linux NET3: IP/IP protocol decoder.
4 *
5 * Authors:
6 * Sam Lantinga (slouken@cs.ucdavis.edu) 02/01/95
7 *
8 * Fixes:
9 * Alan Cox : Merged and made usable non modular (its so tiny its silly as
10 * a module taking up 2 pages).
11 * Alan Cox : Fixed bug with 1.3.18 and IPIP not working (now needs to set skb->h.iph)
12 * to keep ip_forward happy.
13 * Alan Cox : More fixes for 1.3.21, and firewall fix. Maybe this will work soon 8).
14 * Kai Schulte : Fixed #defines for IP_FIREWALL->FIREWALL
15 * David Woodhouse : Perform some basic ICMP handling.
16 * IPIP Routing without decapsulation.
17 * Carlos Picoto : GRE over IP support
18 * Alexey Kuznetsov: Reworked. Really, now it is truncated version of ipv4/ip_gre.c.
19 * I do not want to merge them together.
20 */
21
22 /* tunnel.c: an IP tunnel driver
23
24 The purpose of this driver is to provide an IP tunnel through
25 which you can tunnel network traffic transparently across subnets.
26
27 This was written by looking at Nick Holloway's dummy driver
28 Thanks for the great code!
29
30 -Sam Lantinga (slouken@cs.ucdavis.edu) 02/01/95
31
32 Minor tweaks:
33 Cleaned up the code a little and added some pre-1.3.0 tweaks.
34 dev->hard_header/hard_header_len changed to use no headers.
35 Comments/bracketing tweaked.
36 Made the tunnels use dev->name not tunnel: when error reporting.
37 Added tx_dropped stat
38
39 -Alan Cox (alan@lxorguk.ukuu.org.uk) 21 March 95
40
41 Reworked:
42 Changed to tunnel to destination gateway in addition to the
43 tunnel's pointopoint address
44 Almost completely rewritten
45 Note: There is currently no firewall or ICMP handling done.
46
47 -Sam Lantinga (slouken@cs.ucdavis.edu) 02/13/96
48
49 */
50
51 /* Things I wish I had known when writing the tunnel driver:
52
53 When the tunnel_xmit() function is called, the skb contains the
54 packet to be sent (plus a great deal of extra info), and dev
55 contains the tunnel device that _we_ are.
56
57 When we are passed a packet, we are expected to fill in the
58 source address with our source IP address.
59
60 What is the proper way to allocate, copy and free a buffer?
61 After you allocate it, it is a "0 length" chunk of memory
62 starting at zero. If you want to add headers to the buffer
63 later, you'll have to call "skb_reserve(skb, amount)" with
64 the amount of memory you want reserved. Then, you call
65 "skb_put(skb, amount)" with the amount of space you want in
66 the buffer. skb_put() returns a pointer to the top (#0) of
67 that buffer. skb->len is set to the amount of space you have
68 "allocated" with skb_put(). You can then write up to skb->len
69 bytes to that buffer. If you need more, you can call skb_put()
70 again with the additional amount of space you need. You can
71 find out how much more space you can allocate by calling
72 "skb_tailroom(skb)".
73 Now, to add header space, call "skb_push(skb, header_len)".
74 This creates space at the beginning of the buffer and returns
75 a pointer to this new space. If later you need to strip a
76 header from a buffer, call "skb_pull(skb, header_len)".
77 skb_headroom() will return how much space is left at the top
78 of the buffer (before the main data). Remember, this headroom
79 space must be reserved before the skb_put() function is called.
80 */
81
82 /*
83 This version of net/ipv4/ipip.c is cloned of net/ipv4/ip_gre.c
84
85 For comments look at net/ipv4/ip_gre.c --ANK
86 */
87
88
89 #include <linux/capability.h>
90 #include <linux/module.h>
91 #include <linux/types.h>
92 #include <linux/kernel.h>
93 #include <linux/slab.h>
94 #include <linux/uaccess.h>
95 #include <linux/skbuff.h>
96 #include <linux/netdevice.h>
97 #include <linux/in.h>
98 #include <linux/tcp.h>
99 #include <linux/udp.h>
100 #include <linux/if_arp.h>
101 #include <linux/init.h>
102 #include <linux/netfilter_ipv4.h>
103 #include <linux/if_ether.h>
104
105 #include <net/sock.h>
106 #include <net/ip.h>
107 #include <net/icmp.h>
108 #include <net/ip_tunnels.h>
109 #include <net/inet_ecn.h>
110 #include <net/xfrm.h>
111 #include <net/net_namespace.h>
112 #include <net/netns/generic.h>
113 #include <net/dst_metadata.h>
114
115 static bool log_ecn_error = true;
116 module_param(log_ecn_error, bool, 0644);
117 MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN");
118
119 static unsigned int ipip_net_id __read_mostly;
120
121 static int ipip_tunnel_init(struct net_device *dev);
122 static struct rtnl_link_ops ipip_link_ops __read_mostly;
123
ipip_err(struct sk_buff * skb,u32 info)124 static int ipip_err(struct sk_buff *skb, u32 info)
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 struct net *net = dev_net(skb->dev);
131 struct ip_tunnel_net *itn = net_generic(net, ipip_net_id);
132 const struct iphdr *iph = (const struct iphdr *)skb->data;
133 const int type = icmp_hdr(skb)->type;
134 const int code = icmp_hdr(skb)->code;
135 struct ip_tunnel *t;
136 int err = 0;
137
138 t = ip_tunnel_lookup(itn, skb->dev->ifindex, TUNNEL_NO_KEY,
139 iph->daddr, iph->saddr, 0);
140 if (!t) {
141 err = -ENOENT;
142 goto out;
143 }
144
145 switch (type) {
146 case ICMP_DEST_UNREACH:
147 switch (code) {
148 case ICMP_SR_FAILED:
149 /* Impossible event. */
150 goto out;
151 default:
152 /* All others are translated to HOST_UNREACH.
153 * rfc2003 contains "deep thoughts" about NET_UNREACH,
154 * I believe they are just ether pollution. --ANK
155 */
156 break;
157 }
158 break;
159
160 case ICMP_TIME_EXCEEDED:
161 if (code != ICMP_EXC_TTL)
162 goto out;
163 break;
164
165 case ICMP_REDIRECT:
166 break;
167
168 default:
169 goto out;
170 }
171
172 if (type == ICMP_DEST_UNREACH && code == ICMP_FRAG_NEEDED) {
173 ipv4_update_pmtu(skb, net, info, t->parms.link, iph->protocol);
174 goto out;
175 }
176
177 if (type == ICMP_REDIRECT) {
178 ipv4_redirect(skb, net, t->parms.link, iph->protocol);
179 goto out;
180 }
181
182 if (t->parms.iph.daddr == 0) {
183 err = -ENOENT;
184 goto out;
185 }
186
187 if (t->parms.iph.ttl == 0 && type == ICMP_TIME_EXCEEDED)
188 goto out;
189
190 if (time_before(jiffies, t->err_time + IPTUNNEL_ERR_TIMEO))
191 t->err_count++;
192 else
193 t->err_count = 1;
194 t->err_time = jiffies;
195
196 out:
197 return err;
198 }
199
200 static const struct tnl_ptk_info ipip_tpi = {
201 /* no tunnel info required for ipip. */
202 .proto = htons(ETH_P_IP),
203 };
204
205 #if IS_ENABLED(CONFIG_MPLS)
206 static const struct tnl_ptk_info mplsip_tpi = {
207 /* no tunnel info required for mplsip. */
208 .proto = htons(ETH_P_MPLS_UC),
209 };
210 #endif
211
ipip_tunnel_rcv(struct sk_buff * skb,u8 ipproto)212 static int ipip_tunnel_rcv(struct sk_buff *skb, u8 ipproto)
213 {
214 struct net *net = dev_net(skb->dev);
215 struct ip_tunnel_net *itn = net_generic(net, ipip_net_id);
216 struct metadata_dst *tun_dst = NULL;
217 struct ip_tunnel *tunnel;
218 const struct iphdr *iph;
219
220 iph = ip_hdr(skb);
221 tunnel = ip_tunnel_lookup(itn, skb->dev->ifindex, TUNNEL_NO_KEY,
222 iph->saddr, iph->daddr, 0);
223 if (tunnel) {
224 const struct tnl_ptk_info *tpi;
225
226 if (tunnel->parms.iph.protocol != ipproto &&
227 tunnel->parms.iph.protocol != 0)
228 goto drop;
229
230 if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb))
231 goto drop;
232 #if IS_ENABLED(CONFIG_MPLS)
233 if (ipproto == IPPROTO_MPLS)
234 tpi = &mplsip_tpi;
235 else
236 #endif
237 tpi = &ipip_tpi;
238 if (iptunnel_pull_header(skb, 0, tpi->proto, false))
239 goto drop;
240 if (tunnel->collect_md) {
241 tun_dst = ip_tun_rx_dst(skb, 0, 0, 0);
242 if (!tun_dst)
243 return 0;
244 ip_tunnel_md_udp_encap(skb, &tun_dst->u.tun_info);
245 }
246 skb_reset_mac_header(skb);
247
248 return ip_tunnel_rcv(tunnel, skb, tpi, tun_dst, log_ecn_error);
249 }
250
251 return -1;
252
253 drop:
254 kfree_skb(skb);
255 return 0;
256 }
257
ipip_rcv(struct sk_buff * skb)258 static int ipip_rcv(struct sk_buff *skb)
259 {
260 return ipip_tunnel_rcv(skb, IPPROTO_IPIP);
261 }
262
263 #if IS_ENABLED(CONFIG_MPLS)
mplsip_rcv(struct sk_buff * skb)264 static int mplsip_rcv(struct sk_buff *skb)
265 {
266 return ipip_tunnel_rcv(skb, IPPROTO_MPLS);
267 }
268 #endif
269
270 /*
271 * This function assumes it is being called from dev_queue_xmit()
272 * and that skb is filled properly by that function.
273 */
ipip_tunnel_xmit(struct sk_buff * skb,struct net_device * dev)274 static netdev_tx_t ipip_tunnel_xmit(struct sk_buff *skb,
275 struct net_device *dev)
276 {
277 struct ip_tunnel *tunnel = netdev_priv(dev);
278 const struct iphdr *tiph = &tunnel->parms.iph;
279 u8 ipproto;
280
281 if (!pskb_inet_may_pull(skb))
282 goto tx_error;
283
284 switch (skb->protocol) {
285 case htons(ETH_P_IP):
286 ipproto = IPPROTO_IPIP;
287 break;
288 #if IS_ENABLED(CONFIG_MPLS)
289 case htons(ETH_P_MPLS_UC):
290 ipproto = IPPROTO_MPLS;
291 break;
292 #endif
293 default:
294 goto tx_error;
295 }
296
297 if (tiph->protocol != ipproto && tiph->protocol != 0)
298 goto tx_error;
299
300 if (iptunnel_handle_offloads(skb, SKB_GSO_IPXIP4))
301 goto tx_error;
302
303 skb_set_inner_ipproto(skb, ipproto);
304
305 if (tunnel->collect_md)
306 ip_md_tunnel_xmit(skb, dev, ipproto, 0);
307 else
308 ip_tunnel_xmit(skb, dev, tiph, ipproto);
309 return NETDEV_TX_OK;
310
311 tx_error:
312 kfree_skb(skb);
313
314 DEV_STATS_INC(dev, tx_errors);
315 return NETDEV_TX_OK;
316 }
317
ipip_tunnel_ioctl_verify_protocol(u8 ipproto)318 static bool ipip_tunnel_ioctl_verify_protocol(u8 ipproto)
319 {
320 switch (ipproto) {
321 case 0:
322 case IPPROTO_IPIP:
323 #if IS_ENABLED(CONFIG_MPLS)
324 case IPPROTO_MPLS:
325 #endif
326 return true;
327 }
328
329 return false;
330 }
331
332 static int
ipip_tunnel_ctl(struct net_device * dev,struct ip_tunnel_parm * p,int cmd)333 ipip_tunnel_ctl(struct net_device *dev, struct ip_tunnel_parm *p, int cmd)
334 {
335 if (cmd == SIOCADDTUNNEL || cmd == SIOCCHGTUNNEL) {
336 if (p->iph.version != 4 ||
337 !ipip_tunnel_ioctl_verify_protocol(p->iph.protocol) ||
338 p->iph.ihl != 5 || (p->iph.frag_off & htons(~IP_DF)))
339 return -EINVAL;
340 }
341
342 p->i_key = p->o_key = 0;
343 p->i_flags = p->o_flags = 0;
344 return ip_tunnel_ctl(dev, p, cmd);
345 }
346
347 static const struct net_device_ops ipip_netdev_ops = {
348 .ndo_init = ipip_tunnel_init,
349 .ndo_uninit = ip_tunnel_uninit,
350 .ndo_start_xmit = ipip_tunnel_xmit,
351 .ndo_siocdevprivate = ip_tunnel_siocdevprivate,
352 .ndo_change_mtu = ip_tunnel_change_mtu,
353 .ndo_get_stats64 = dev_get_tstats64,
354 .ndo_get_iflink = ip_tunnel_get_iflink,
355 .ndo_tunnel_ctl = ipip_tunnel_ctl,
356 };
357
358 #define IPIP_FEATURES (NETIF_F_SG | \
359 NETIF_F_FRAGLIST | \
360 NETIF_F_HIGHDMA | \
361 NETIF_F_GSO_SOFTWARE | \
362 NETIF_F_HW_CSUM)
363
ipip_tunnel_setup(struct net_device * dev)364 static void ipip_tunnel_setup(struct net_device *dev)
365 {
366 dev->netdev_ops = &ipip_netdev_ops;
367 dev->header_ops = &ip_tunnel_header_ops;
368
369 dev->type = ARPHRD_TUNNEL;
370 dev->flags = IFF_NOARP;
371 dev->addr_len = 4;
372 dev->features |= NETIF_F_LLTX;
373 netif_keep_dst(dev);
374
375 dev->features |= IPIP_FEATURES;
376 dev->hw_features |= IPIP_FEATURES;
377 ip_tunnel_setup(dev, ipip_net_id);
378 }
379
ipip_tunnel_init(struct net_device * dev)380 static int ipip_tunnel_init(struct net_device *dev)
381 {
382 struct ip_tunnel *tunnel = netdev_priv(dev);
383
384 __dev_addr_set(dev, &tunnel->parms.iph.saddr, 4);
385 memcpy(dev->broadcast, &tunnel->parms.iph.daddr, 4);
386
387 tunnel->tun_hlen = 0;
388 tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen;
389 return ip_tunnel_init(dev);
390 }
391
ipip_tunnel_validate(struct nlattr * tb[],struct nlattr * data[],struct netlink_ext_ack * extack)392 static int ipip_tunnel_validate(struct nlattr *tb[], struct nlattr *data[],
393 struct netlink_ext_ack *extack)
394 {
395 u8 proto;
396
397 if (!data || !data[IFLA_IPTUN_PROTO])
398 return 0;
399
400 proto = nla_get_u8(data[IFLA_IPTUN_PROTO]);
401 if (proto != IPPROTO_IPIP && proto != IPPROTO_MPLS && proto != 0)
402 return -EINVAL;
403
404 return 0;
405 }
406
ipip_netlink_parms(struct nlattr * data[],struct ip_tunnel_parm * parms,bool * collect_md,__u32 * fwmark)407 static void ipip_netlink_parms(struct nlattr *data[],
408 struct ip_tunnel_parm *parms, bool *collect_md,
409 __u32 *fwmark)
410 {
411 memset(parms, 0, sizeof(*parms));
412
413 parms->iph.version = 4;
414 parms->iph.protocol = IPPROTO_IPIP;
415 parms->iph.ihl = 5;
416 *collect_md = false;
417
418 if (!data)
419 return;
420
421 ip_tunnel_netlink_parms(data, parms);
422
423 if (data[IFLA_IPTUN_COLLECT_METADATA])
424 *collect_md = true;
425
426 if (data[IFLA_IPTUN_FWMARK])
427 *fwmark = nla_get_u32(data[IFLA_IPTUN_FWMARK]);
428 }
429
ipip_newlink(struct net * src_net,struct net_device * dev,struct nlattr * tb[],struct nlattr * data[],struct netlink_ext_ack * extack)430 static int ipip_newlink(struct net *src_net, struct net_device *dev,
431 struct nlattr *tb[], struct nlattr *data[],
432 struct netlink_ext_ack *extack)
433 {
434 struct ip_tunnel *t = netdev_priv(dev);
435 struct ip_tunnel_parm p;
436 struct ip_tunnel_encap ipencap;
437 __u32 fwmark = 0;
438
439 if (ip_tunnel_netlink_encap_parms(data, &ipencap)) {
440 int err = ip_tunnel_encap_setup(t, &ipencap);
441
442 if (err < 0)
443 return err;
444 }
445
446 ipip_netlink_parms(data, &p, &t->collect_md, &fwmark);
447 return ip_tunnel_newlink(dev, tb, &p, fwmark);
448 }
449
ipip_changelink(struct net_device * dev,struct nlattr * tb[],struct nlattr * data[],struct netlink_ext_ack * extack)450 static int ipip_changelink(struct net_device *dev, struct nlattr *tb[],
451 struct nlattr *data[],
452 struct netlink_ext_ack *extack)
453 {
454 struct ip_tunnel *t = netdev_priv(dev);
455 struct ip_tunnel_parm p;
456 struct ip_tunnel_encap ipencap;
457 bool collect_md;
458 __u32 fwmark = t->fwmark;
459
460 if (ip_tunnel_netlink_encap_parms(data, &ipencap)) {
461 int err = ip_tunnel_encap_setup(t, &ipencap);
462
463 if (err < 0)
464 return err;
465 }
466
467 ipip_netlink_parms(data, &p, &collect_md, &fwmark);
468 if (collect_md)
469 return -EINVAL;
470
471 if (((dev->flags & IFF_POINTOPOINT) && !p.iph.daddr) ||
472 (!(dev->flags & IFF_POINTOPOINT) && p.iph.daddr))
473 return -EINVAL;
474
475 return ip_tunnel_changelink(dev, tb, &p, fwmark);
476 }
477
ipip_get_size(const struct net_device * dev)478 static size_t ipip_get_size(const struct net_device *dev)
479 {
480 return
481 /* IFLA_IPTUN_LINK */
482 nla_total_size(4) +
483 /* IFLA_IPTUN_LOCAL */
484 nla_total_size(4) +
485 /* IFLA_IPTUN_REMOTE */
486 nla_total_size(4) +
487 /* IFLA_IPTUN_TTL */
488 nla_total_size(1) +
489 /* IFLA_IPTUN_TOS */
490 nla_total_size(1) +
491 /* IFLA_IPTUN_PROTO */
492 nla_total_size(1) +
493 /* IFLA_IPTUN_PMTUDISC */
494 nla_total_size(1) +
495 /* IFLA_IPTUN_ENCAP_TYPE */
496 nla_total_size(2) +
497 /* IFLA_IPTUN_ENCAP_FLAGS */
498 nla_total_size(2) +
499 /* IFLA_IPTUN_ENCAP_SPORT */
500 nla_total_size(2) +
501 /* IFLA_IPTUN_ENCAP_DPORT */
502 nla_total_size(2) +
503 /* IFLA_IPTUN_COLLECT_METADATA */
504 nla_total_size(0) +
505 /* IFLA_IPTUN_FWMARK */
506 nla_total_size(4) +
507 0;
508 }
509
ipip_fill_info(struct sk_buff * skb,const struct net_device * dev)510 static int ipip_fill_info(struct sk_buff *skb, const struct net_device *dev)
511 {
512 struct ip_tunnel *tunnel = netdev_priv(dev);
513 struct ip_tunnel_parm *parm = &tunnel->parms;
514
515 if (nla_put_u32(skb, IFLA_IPTUN_LINK, parm->link) ||
516 nla_put_in_addr(skb, IFLA_IPTUN_LOCAL, parm->iph.saddr) ||
517 nla_put_in_addr(skb, IFLA_IPTUN_REMOTE, parm->iph.daddr) ||
518 nla_put_u8(skb, IFLA_IPTUN_TTL, parm->iph.ttl) ||
519 nla_put_u8(skb, IFLA_IPTUN_TOS, parm->iph.tos) ||
520 nla_put_u8(skb, IFLA_IPTUN_PROTO, parm->iph.protocol) ||
521 nla_put_u8(skb, IFLA_IPTUN_PMTUDISC,
522 !!(parm->iph.frag_off & htons(IP_DF))) ||
523 nla_put_u32(skb, IFLA_IPTUN_FWMARK, tunnel->fwmark))
524 goto nla_put_failure;
525
526 if (nla_put_u16(skb, IFLA_IPTUN_ENCAP_TYPE,
527 tunnel->encap.type) ||
528 nla_put_be16(skb, IFLA_IPTUN_ENCAP_SPORT,
529 tunnel->encap.sport) ||
530 nla_put_be16(skb, IFLA_IPTUN_ENCAP_DPORT,
531 tunnel->encap.dport) ||
532 nla_put_u16(skb, IFLA_IPTUN_ENCAP_FLAGS,
533 tunnel->encap.flags))
534 goto nla_put_failure;
535
536 if (tunnel->collect_md)
537 if (nla_put_flag(skb, IFLA_IPTUN_COLLECT_METADATA))
538 goto nla_put_failure;
539 return 0;
540
541 nla_put_failure:
542 return -EMSGSIZE;
543 }
544
545 static const struct nla_policy ipip_policy[IFLA_IPTUN_MAX + 1] = {
546 [IFLA_IPTUN_LINK] = { .type = NLA_U32 },
547 [IFLA_IPTUN_LOCAL] = { .type = NLA_U32 },
548 [IFLA_IPTUN_REMOTE] = { .type = NLA_U32 },
549 [IFLA_IPTUN_TTL] = { .type = NLA_U8 },
550 [IFLA_IPTUN_TOS] = { .type = NLA_U8 },
551 [IFLA_IPTUN_PROTO] = { .type = NLA_U8 },
552 [IFLA_IPTUN_PMTUDISC] = { .type = NLA_U8 },
553 [IFLA_IPTUN_ENCAP_TYPE] = { .type = NLA_U16 },
554 [IFLA_IPTUN_ENCAP_FLAGS] = { .type = NLA_U16 },
555 [IFLA_IPTUN_ENCAP_SPORT] = { .type = NLA_U16 },
556 [IFLA_IPTUN_ENCAP_DPORT] = { .type = NLA_U16 },
557 [IFLA_IPTUN_COLLECT_METADATA] = { .type = NLA_FLAG },
558 [IFLA_IPTUN_FWMARK] = { .type = NLA_U32 },
559 };
560
561 static struct rtnl_link_ops ipip_link_ops __read_mostly = {
562 .kind = "ipip",
563 .maxtype = IFLA_IPTUN_MAX,
564 .policy = ipip_policy,
565 .priv_size = sizeof(struct ip_tunnel),
566 .setup = ipip_tunnel_setup,
567 .validate = ipip_tunnel_validate,
568 .newlink = ipip_newlink,
569 .changelink = ipip_changelink,
570 .dellink = ip_tunnel_dellink,
571 .get_size = ipip_get_size,
572 .fill_info = ipip_fill_info,
573 .get_link_net = ip_tunnel_get_link_net,
574 };
575
576 static struct xfrm_tunnel ipip_handler __read_mostly = {
577 .handler = ipip_rcv,
578 .err_handler = ipip_err,
579 .priority = 1,
580 };
581
582 #if IS_ENABLED(CONFIG_MPLS)
583 static struct xfrm_tunnel mplsip_handler __read_mostly = {
584 .handler = mplsip_rcv,
585 .err_handler = ipip_err,
586 .priority = 1,
587 };
588 #endif
589
ipip_init_net(struct net * net)590 static int __net_init ipip_init_net(struct net *net)
591 {
592 return ip_tunnel_init_net(net, ipip_net_id, &ipip_link_ops, "tunl0");
593 }
594
ipip_exit_batch_net(struct list_head * list_net)595 static void __net_exit ipip_exit_batch_net(struct list_head *list_net)
596 {
597 ip_tunnel_delete_nets(list_net, ipip_net_id, &ipip_link_ops);
598 }
599
600 static struct pernet_operations ipip_net_ops = {
601 .init = ipip_init_net,
602 .exit_batch = ipip_exit_batch_net,
603 .id = &ipip_net_id,
604 .size = sizeof(struct ip_tunnel_net),
605 };
606
ipip_init(void)607 static int __init ipip_init(void)
608 {
609 int err;
610
611 pr_info("ipip: IPv4 and MPLS over IPv4 tunneling driver\n");
612
613 err = register_pernet_device(&ipip_net_ops);
614 if (err < 0)
615 return err;
616 err = xfrm4_tunnel_register(&ipip_handler, AF_INET);
617 if (err < 0) {
618 pr_info("%s: can't register tunnel\n", __func__);
619 goto xfrm_tunnel_ipip_failed;
620 }
621 #if IS_ENABLED(CONFIG_MPLS)
622 err = xfrm4_tunnel_register(&mplsip_handler, AF_MPLS);
623 if (err < 0) {
624 pr_info("%s: can't register tunnel\n", __func__);
625 goto xfrm_tunnel_mplsip_failed;
626 }
627 #endif
628 err = rtnl_link_register(&ipip_link_ops);
629 if (err < 0)
630 goto rtnl_link_failed;
631
632 out:
633 return err;
634
635 rtnl_link_failed:
636 #if IS_ENABLED(CONFIG_MPLS)
637 xfrm4_tunnel_deregister(&mplsip_handler, AF_MPLS);
638 xfrm_tunnel_mplsip_failed:
639
640 #endif
641 xfrm4_tunnel_deregister(&ipip_handler, AF_INET);
642 xfrm_tunnel_ipip_failed:
643 unregister_pernet_device(&ipip_net_ops);
644 goto out;
645 }
646
ipip_fini(void)647 static void __exit ipip_fini(void)
648 {
649 rtnl_link_unregister(&ipip_link_ops);
650 if (xfrm4_tunnel_deregister(&ipip_handler, AF_INET))
651 pr_info("%s: can't deregister tunnel\n", __func__);
652 #if IS_ENABLED(CONFIG_MPLS)
653 if (xfrm4_tunnel_deregister(&mplsip_handler, AF_MPLS))
654 pr_info("%s: can't deregister tunnel\n", __func__);
655 #endif
656 unregister_pernet_device(&ipip_net_ops);
657 }
658
659 module_init(ipip_init);
660 module_exit(ipip_fini);
661 MODULE_LICENSE("GPL");
662 MODULE_ALIAS_RTNL_LINK("ipip");
663 MODULE_ALIAS_NETDEV("tunl0");
664