Loading...
1/*
2 * Linux NET3: IP/IP protocol decoder.
3 *
4 * Authors:
5 * Sam Lantinga (slouken@cs.ucdavis.edu) 02/01/95
6 *
7 * Fixes:
8 * Alan Cox : Merged and made usable non modular (its so tiny its silly as
9 * a module taking up 2 pages).
10 * Alan Cox : Fixed bug with 1.3.18 and IPIP not working (now needs to set skb->h.iph)
11 * to keep ip_forward happy.
12 * Alan Cox : More fixes for 1.3.21, and firewall fix. Maybe this will work soon 8).
13 * Kai Schulte : Fixed #defines for IP_FIREWALL->FIREWALL
14 * David Woodhouse : Perform some basic ICMP handling.
15 * IPIP Routing without decapsulation.
16 * Carlos Picoto : GRE over IP support
17 * Alexey Kuznetsov: Reworked. Really, now it is truncated version of ipv4/ip_gre.c.
18 * I do not want to merge them together.
19 *
20 * This program is free software; you can redistribute it and/or
21 * modify it under the terms of the GNU General Public License
22 * as published by the Free Software Foundation; either version
23 * 2 of the License, or (at your option) any later version.
24 *
25 */
26
27/* tunnel.c: an IP tunnel driver
28
29 The purpose of this driver is to provide an IP tunnel through
30 which you can tunnel network traffic transparently across subnets.
31
32 This was written by looking at Nick Holloway's dummy driver
33 Thanks for the great code!
34
35 -Sam Lantinga (slouken@cs.ucdavis.edu) 02/01/95
36
37 Minor tweaks:
38 Cleaned up the code a little and added some pre-1.3.0 tweaks.
39 dev->hard_header/hard_header_len changed to use no headers.
40 Comments/bracketing tweaked.
41 Made the tunnels use dev->name not tunnel: when error reporting.
42 Added tx_dropped stat
43
44 -Alan Cox (alan@lxorguk.ukuu.org.uk) 21 March 95
45
46 Reworked:
47 Changed to tunnel to destination gateway in addition to the
48 tunnel's pointopoint address
49 Almost completely rewritten
50 Note: There is currently no firewall or ICMP handling done.
51
52 -Sam Lantinga (slouken@cs.ucdavis.edu) 02/13/96
53
54*/
55
56/* Things I wish I had known when writing the tunnel driver:
57
58 When the tunnel_xmit() function is called, the skb contains the
59 packet to be sent (plus a great deal of extra info), and dev
60 contains the tunnel device that _we_ are.
61
62 When we are passed a packet, we are expected to fill in the
63 source address with our source IP address.
64
65 What is the proper way to allocate, copy and free a buffer?
66 After you allocate it, it is a "0 length" chunk of memory
67 starting at zero. If you want to add headers to the buffer
68 later, you'll have to call "skb_reserve(skb, amount)" with
69 the amount of memory you want reserved. Then, you call
70 "skb_put(skb, amount)" with the amount of space you want in
71 the buffer. skb_put() returns a pointer to the top (#0) of
72 that buffer. skb->len is set to the amount of space you have
73 "allocated" with skb_put(). You can then write up to skb->len
74 bytes to that buffer. If you need more, you can call skb_put()
75 again with the additional amount of space you need. You can
76 find out how much more space you can allocate by calling
77 "skb_tailroom(skb)".
78 Now, to add header space, call "skb_push(skb, header_len)".
79 This creates space at the beginning of the buffer and returns
80 a pointer to this new space. If later you need to strip a
81 header from a buffer, call "skb_pull(skb, header_len)".
82 skb_headroom() will return how much space is left at the top
83 of the buffer (before the main data). Remember, this headroom
84 space must be reserved before the skb_put() function is called.
85 */
86
87/*
88 This version of net/ipv4/ipip.c is cloned of net/ipv4/ip_gre.c
89
90 For comments look at net/ipv4/ip_gre.c --ANK
91 */
92
93
94#include <linux/capability.h>
95#include <linux/module.h>
96#include <linux/types.h>
97#include <linux/kernel.h>
98#include <linux/slab.h>
99#include <asm/uaccess.h>
100#include <linux/skbuff.h>
101#include <linux/netdevice.h>
102#include <linux/in.h>
103#include <linux/tcp.h>
104#include <linux/udp.h>
105#include <linux/if_arp.h>
106#include <linux/mroute.h>
107#include <linux/init.h>
108#include <linux/netfilter_ipv4.h>
109#include <linux/if_ether.h>
110
111#include <net/sock.h>
112#include <net/ip.h>
113#include <net/icmp.h>
114#include <net/ipip.h>
115#include <net/inet_ecn.h>
116#include <net/xfrm.h>
117#include <net/net_namespace.h>
118#include <net/netns/generic.h>
119
120#define HASH_SIZE 16
121#define HASH(addr) (((__force u32)addr^((__force u32)addr>>4))&0xF)
122
123static int ipip_net_id __read_mostly;
124struct ipip_net {
125 struct ip_tunnel __rcu *tunnels_r_l[HASH_SIZE];
126 struct ip_tunnel __rcu *tunnels_r[HASH_SIZE];
127 struct ip_tunnel __rcu *tunnels_l[HASH_SIZE];
128 struct ip_tunnel __rcu *tunnels_wc[1];
129 struct ip_tunnel __rcu **tunnels[4];
130
131 struct net_device *fb_tunnel_dev;
132};
133
134static int ipip_tunnel_init(struct net_device *dev);
135static void ipip_tunnel_setup(struct net_device *dev);
136static void ipip_dev_free(struct net_device *dev);
137
138/*
139 * Locking : hash tables are protected by RCU and RTNL
140 */
141
142#define for_each_ip_tunnel_rcu(start) \
143 for (t = rcu_dereference(start); t; t = rcu_dereference(t->next))
144
145/* often modified stats are per cpu, other are shared (netdev->stats) */
146struct pcpu_tstats {
147 unsigned long rx_packets;
148 unsigned long rx_bytes;
149 unsigned long tx_packets;
150 unsigned long tx_bytes;
151};
152
153static struct net_device_stats *ipip_get_stats(struct net_device *dev)
154{
155 struct pcpu_tstats sum = { 0 };
156 int i;
157
158 for_each_possible_cpu(i) {
159 const struct pcpu_tstats *tstats = per_cpu_ptr(dev->tstats, i);
160
161 sum.rx_packets += tstats->rx_packets;
162 sum.rx_bytes += tstats->rx_bytes;
163 sum.tx_packets += tstats->tx_packets;
164 sum.tx_bytes += tstats->tx_bytes;
165 }
166 dev->stats.rx_packets = sum.rx_packets;
167 dev->stats.rx_bytes = sum.rx_bytes;
168 dev->stats.tx_packets = sum.tx_packets;
169 dev->stats.tx_bytes = sum.tx_bytes;
170 return &dev->stats;
171}
172
173static struct ip_tunnel * ipip_tunnel_lookup(struct net *net,
174 __be32 remote, __be32 local)
175{
176 unsigned int h0 = HASH(remote);
177 unsigned int h1 = HASH(local);
178 struct ip_tunnel *t;
179 struct ipip_net *ipn = net_generic(net, ipip_net_id);
180
181 for_each_ip_tunnel_rcu(ipn->tunnels_r_l[h0 ^ h1])
182 if (local == t->parms.iph.saddr &&
183 remote == t->parms.iph.daddr && (t->dev->flags&IFF_UP))
184 return t;
185
186 for_each_ip_tunnel_rcu(ipn->tunnels_r[h0])
187 if (remote == t->parms.iph.daddr && (t->dev->flags&IFF_UP))
188 return t;
189
190 for_each_ip_tunnel_rcu(ipn->tunnels_l[h1])
191 if (local == t->parms.iph.saddr && (t->dev->flags&IFF_UP))
192 return t;
193
194 t = rcu_dereference(ipn->tunnels_wc[0]);
195 if (t && (t->dev->flags&IFF_UP))
196 return t;
197 return NULL;
198}
199
200static struct ip_tunnel __rcu **__ipip_bucket(struct ipip_net *ipn,
201 struct ip_tunnel_parm *parms)
202{
203 __be32 remote = parms->iph.daddr;
204 __be32 local = parms->iph.saddr;
205 unsigned int h = 0;
206 int prio = 0;
207
208 if (remote) {
209 prio |= 2;
210 h ^= HASH(remote);
211 }
212 if (local) {
213 prio |= 1;
214 h ^= HASH(local);
215 }
216 return &ipn->tunnels[prio][h];
217}
218
219static inline struct ip_tunnel __rcu **ipip_bucket(struct ipip_net *ipn,
220 struct ip_tunnel *t)
221{
222 return __ipip_bucket(ipn, &t->parms);
223}
224
225static void ipip_tunnel_unlink(struct ipip_net *ipn, struct ip_tunnel *t)
226{
227 struct ip_tunnel __rcu **tp;
228 struct ip_tunnel *iter;
229
230 for (tp = ipip_bucket(ipn, t);
231 (iter = rtnl_dereference(*tp)) != NULL;
232 tp = &iter->next) {
233 if (t == iter) {
234 rcu_assign_pointer(*tp, t->next);
235 break;
236 }
237 }
238}
239
240static void ipip_tunnel_link(struct ipip_net *ipn, struct ip_tunnel *t)
241{
242 struct ip_tunnel __rcu **tp = ipip_bucket(ipn, t);
243
244 rcu_assign_pointer(t->next, rtnl_dereference(*tp));
245 rcu_assign_pointer(*tp, t);
246}
247
248static struct ip_tunnel * ipip_tunnel_locate(struct net *net,
249 struct ip_tunnel_parm *parms, int create)
250{
251 __be32 remote = parms->iph.daddr;
252 __be32 local = parms->iph.saddr;
253 struct ip_tunnel *t, *nt;
254 struct ip_tunnel __rcu **tp;
255 struct net_device *dev;
256 char name[IFNAMSIZ];
257 struct ipip_net *ipn = net_generic(net, ipip_net_id);
258
259 for (tp = __ipip_bucket(ipn, parms);
260 (t = rtnl_dereference(*tp)) != NULL;
261 tp = &t->next) {
262 if (local == t->parms.iph.saddr && remote == t->parms.iph.daddr)
263 return t;
264 }
265 if (!create)
266 return NULL;
267
268 if (parms->name[0])
269 strlcpy(name, parms->name, IFNAMSIZ);
270 else
271 strcpy(name, "tunl%d");
272
273 dev = alloc_netdev(sizeof(*t), name, ipip_tunnel_setup);
274 if (dev == NULL)
275 return NULL;
276
277 dev_net_set(dev, net);
278
279 nt = netdev_priv(dev);
280 nt->parms = *parms;
281
282 if (ipip_tunnel_init(dev) < 0)
283 goto failed_free;
284
285 if (register_netdevice(dev) < 0)
286 goto failed_free;
287
288 dev_hold(dev);
289 ipip_tunnel_link(ipn, nt);
290 return nt;
291
292failed_free:
293 ipip_dev_free(dev);
294 return NULL;
295}
296
297/* called with RTNL */
298static void ipip_tunnel_uninit(struct net_device *dev)
299{
300 struct net *net = dev_net(dev);
301 struct ipip_net *ipn = net_generic(net, ipip_net_id);
302
303 if (dev == ipn->fb_tunnel_dev)
304 rcu_assign_pointer(ipn->tunnels_wc[0], NULL);
305 else
306 ipip_tunnel_unlink(ipn, netdev_priv(dev));
307 dev_put(dev);
308}
309
310static int ipip_err(struct sk_buff *skb, u32 info)
311{
312
313/* All the routers (except for Linux) return only
314 8 bytes of packet payload. It means, that precise relaying of
315 ICMP in the real Internet is absolutely infeasible.
316 */
317 const struct iphdr *iph = (const struct iphdr *)skb->data;
318 const int type = icmp_hdr(skb)->type;
319 const int code = icmp_hdr(skb)->code;
320 struct ip_tunnel *t;
321 int err;
322
323 switch (type) {
324 default:
325 case ICMP_PARAMETERPROB:
326 return 0;
327
328 case ICMP_DEST_UNREACH:
329 switch (code) {
330 case ICMP_SR_FAILED:
331 case ICMP_PORT_UNREACH:
332 /* Impossible event. */
333 return 0;
334 case ICMP_FRAG_NEEDED:
335 /* Soft state for pmtu is maintained by IP core. */
336 return 0;
337 default:
338 /* All others are translated to HOST_UNREACH.
339 rfc2003 contains "deep thoughts" about NET_UNREACH,
340 I believe they are just ether pollution. --ANK
341 */
342 break;
343 }
344 break;
345 case ICMP_TIME_EXCEEDED:
346 if (code != ICMP_EXC_TTL)
347 return 0;
348 break;
349 }
350
351 err = -ENOENT;
352
353 rcu_read_lock();
354 t = ipip_tunnel_lookup(dev_net(skb->dev), iph->daddr, iph->saddr);
355 if (t == NULL || t->parms.iph.daddr == 0)
356 goto out;
357
358 err = 0;
359 if (t->parms.iph.ttl == 0 && type == ICMP_TIME_EXCEEDED)
360 goto out;
361
362 if (time_before(jiffies, t->err_time + IPTUNNEL_ERR_TIMEO))
363 t->err_count++;
364 else
365 t->err_count = 1;
366 t->err_time = jiffies;
367out:
368 rcu_read_unlock();
369 return err;
370}
371
372static inline void ipip_ecn_decapsulate(const struct iphdr *outer_iph,
373 struct sk_buff *skb)
374{
375 struct iphdr *inner_iph = ip_hdr(skb);
376
377 if (INET_ECN_is_ce(outer_iph->tos))
378 IP_ECN_set_ce(inner_iph);
379}
380
381static int ipip_rcv(struct sk_buff *skb)
382{
383 struct ip_tunnel *tunnel;
384 const struct iphdr *iph = ip_hdr(skb);
385
386 rcu_read_lock();
387 tunnel = ipip_tunnel_lookup(dev_net(skb->dev), iph->saddr, iph->daddr);
388 if (tunnel != NULL) {
389 struct pcpu_tstats *tstats;
390
391 if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb)) {
392 rcu_read_unlock();
393 kfree_skb(skb);
394 return 0;
395 }
396
397 secpath_reset(skb);
398
399 skb->mac_header = skb->network_header;
400 skb_reset_network_header(skb);
401 skb->protocol = htons(ETH_P_IP);
402 skb->pkt_type = PACKET_HOST;
403
404 tstats = this_cpu_ptr(tunnel->dev->tstats);
405 tstats->rx_packets++;
406 tstats->rx_bytes += skb->len;
407
408 __skb_tunnel_rx(skb, tunnel->dev);
409
410 ipip_ecn_decapsulate(iph, skb);
411
412 netif_rx(skb);
413
414 rcu_read_unlock();
415 return 0;
416 }
417 rcu_read_unlock();
418
419 return -1;
420}
421
422/*
423 * This function assumes it is being called from dev_queue_xmit()
424 * and that skb is filled properly by that function.
425 */
426
427static netdev_tx_t ipip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev)
428{
429 struct ip_tunnel *tunnel = netdev_priv(dev);
430 struct pcpu_tstats *tstats;
431 const struct iphdr *tiph = &tunnel->parms.iph;
432 u8 tos = tunnel->parms.iph.tos;
433 __be16 df = tiph->frag_off;
434 struct rtable *rt; /* Route to the other host */
435 struct net_device *tdev; /* Device to other host */
436 const struct iphdr *old_iph = ip_hdr(skb);
437 struct iphdr *iph; /* Our new IP header */
438 unsigned int max_headroom; /* The extra header space needed */
439 __be32 dst = tiph->daddr;
440 struct flowi4 fl4;
441 int mtu;
442
443 if (skb->protocol != htons(ETH_P_IP))
444 goto tx_error;
445
446 if (tos & 1)
447 tos = old_iph->tos;
448
449 if (!dst) {
450 /* NBMA tunnel */
451 if ((rt = skb_rtable(skb)) == NULL) {
452 dev->stats.tx_fifo_errors++;
453 goto tx_error;
454 }
455 if ((dst = rt->rt_gateway) == 0)
456 goto tx_error_icmp;
457 }
458
459 rt = ip_route_output_ports(dev_net(dev), &fl4, NULL,
460 dst, tiph->saddr,
461 0, 0,
462 IPPROTO_IPIP, RT_TOS(tos),
463 tunnel->parms.link);
464 if (IS_ERR(rt)) {
465 dev->stats.tx_carrier_errors++;
466 goto tx_error_icmp;
467 }
468 tdev = rt->dst.dev;
469
470 if (tdev == dev) {
471 ip_rt_put(rt);
472 dev->stats.collisions++;
473 goto tx_error;
474 }
475
476 df |= old_iph->frag_off & htons(IP_DF);
477
478 if (df) {
479 mtu = dst_mtu(&rt->dst) - sizeof(struct iphdr);
480
481 if (mtu < 68) {
482 dev->stats.collisions++;
483 ip_rt_put(rt);
484 goto tx_error;
485 }
486
487 if (skb_dst(skb))
488 skb_dst(skb)->ops->update_pmtu(skb_dst(skb), mtu);
489
490 if ((old_iph->frag_off & htons(IP_DF)) &&
491 mtu < ntohs(old_iph->tot_len)) {
492 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
493 htonl(mtu));
494 ip_rt_put(rt);
495 goto tx_error;
496 }
497 }
498
499 if (tunnel->err_count > 0) {
500 if (time_before(jiffies,
501 tunnel->err_time + IPTUNNEL_ERR_TIMEO)) {
502 tunnel->err_count--;
503 dst_link_failure(skb);
504 } else
505 tunnel->err_count = 0;
506 }
507
508 /*
509 * Okay, now see if we can stuff it in the buffer as-is.
510 */
511 max_headroom = (LL_RESERVED_SPACE(tdev)+sizeof(struct iphdr));
512
513 if (skb_headroom(skb) < max_headroom || skb_shared(skb) ||
514 (skb_cloned(skb) && !skb_clone_writable(skb, 0))) {
515 struct sk_buff *new_skb = skb_realloc_headroom(skb, max_headroom);
516 if (!new_skb) {
517 ip_rt_put(rt);
518 dev->stats.tx_dropped++;
519 dev_kfree_skb(skb);
520 return NETDEV_TX_OK;
521 }
522 if (skb->sk)
523 skb_set_owner_w(new_skb, skb->sk);
524 dev_kfree_skb(skb);
525 skb = new_skb;
526 old_iph = ip_hdr(skb);
527 }
528
529 skb->transport_header = skb->network_header;
530 skb_push(skb, sizeof(struct iphdr));
531 skb_reset_network_header(skb);
532 memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
533 IPCB(skb)->flags &= ~(IPSKB_XFRM_TUNNEL_SIZE | IPSKB_XFRM_TRANSFORMED |
534 IPSKB_REROUTED);
535 skb_dst_drop(skb);
536 skb_dst_set(skb, &rt->dst);
537
538 /*
539 * Push down and install the IPIP header.
540 */
541
542 iph = ip_hdr(skb);
543 iph->version = 4;
544 iph->ihl = sizeof(struct iphdr)>>2;
545 iph->frag_off = df;
546 iph->protocol = IPPROTO_IPIP;
547 iph->tos = INET_ECN_encapsulate(tos, old_iph->tos);
548 iph->daddr = fl4.daddr;
549 iph->saddr = fl4.saddr;
550
551 if ((iph->ttl = tiph->ttl) == 0)
552 iph->ttl = old_iph->ttl;
553
554 nf_reset(skb);
555 tstats = this_cpu_ptr(dev->tstats);
556 __IPTUNNEL_XMIT(tstats, &dev->stats);
557 return NETDEV_TX_OK;
558
559tx_error_icmp:
560 dst_link_failure(skb);
561tx_error:
562 dev->stats.tx_errors++;
563 dev_kfree_skb(skb);
564 return NETDEV_TX_OK;
565}
566
567static void ipip_tunnel_bind_dev(struct net_device *dev)
568{
569 struct net_device *tdev = NULL;
570 struct ip_tunnel *tunnel;
571 const struct iphdr *iph;
572
573 tunnel = netdev_priv(dev);
574 iph = &tunnel->parms.iph;
575
576 if (iph->daddr) {
577 struct rtable *rt;
578 struct flowi4 fl4;
579
580 rt = ip_route_output_ports(dev_net(dev), &fl4, NULL,
581 iph->daddr, iph->saddr,
582 0, 0,
583 IPPROTO_IPIP,
584 RT_TOS(iph->tos),
585 tunnel->parms.link);
586 if (!IS_ERR(rt)) {
587 tdev = rt->dst.dev;
588 ip_rt_put(rt);
589 }
590 dev->flags |= IFF_POINTOPOINT;
591 }
592
593 if (!tdev && tunnel->parms.link)
594 tdev = __dev_get_by_index(dev_net(dev), tunnel->parms.link);
595
596 if (tdev) {
597 dev->hard_header_len = tdev->hard_header_len + sizeof(struct iphdr);
598 dev->mtu = tdev->mtu - sizeof(struct iphdr);
599 }
600 dev->iflink = tunnel->parms.link;
601}
602
603static int
604ipip_tunnel_ioctl (struct net_device *dev, struct ifreq *ifr, int cmd)
605{
606 int err = 0;
607 struct ip_tunnel_parm p;
608 struct ip_tunnel *t;
609 struct net *net = dev_net(dev);
610 struct ipip_net *ipn = net_generic(net, ipip_net_id);
611
612 switch (cmd) {
613 case SIOCGETTUNNEL:
614 t = NULL;
615 if (dev == ipn->fb_tunnel_dev) {
616 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) {
617 err = -EFAULT;
618 break;
619 }
620 t = ipip_tunnel_locate(net, &p, 0);
621 }
622 if (t == NULL)
623 t = netdev_priv(dev);
624 memcpy(&p, &t->parms, sizeof(p));
625 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
626 err = -EFAULT;
627 break;
628
629 case SIOCADDTUNNEL:
630 case SIOCCHGTUNNEL:
631 err = -EPERM;
632 if (!capable(CAP_NET_ADMIN))
633 goto done;
634
635 err = -EFAULT;
636 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
637 goto done;
638
639 err = -EINVAL;
640 if (p.iph.version != 4 || p.iph.protocol != IPPROTO_IPIP ||
641 p.iph.ihl != 5 || (p.iph.frag_off&htons(~IP_DF)))
642 goto done;
643 if (p.iph.ttl)
644 p.iph.frag_off |= htons(IP_DF);
645
646 t = ipip_tunnel_locate(net, &p, cmd == SIOCADDTUNNEL);
647
648 if (dev != ipn->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) {
649 if (t != NULL) {
650 if (t->dev != dev) {
651 err = -EEXIST;
652 break;
653 }
654 } else {
655 if (((dev->flags&IFF_POINTOPOINT) && !p.iph.daddr) ||
656 (!(dev->flags&IFF_POINTOPOINT) && p.iph.daddr)) {
657 err = -EINVAL;
658 break;
659 }
660 t = netdev_priv(dev);
661 ipip_tunnel_unlink(ipn, t);
662 synchronize_net();
663 t->parms.iph.saddr = p.iph.saddr;
664 t->parms.iph.daddr = p.iph.daddr;
665 memcpy(dev->dev_addr, &p.iph.saddr, 4);
666 memcpy(dev->broadcast, &p.iph.daddr, 4);
667 ipip_tunnel_link(ipn, t);
668 netdev_state_change(dev);
669 }
670 }
671
672 if (t) {
673 err = 0;
674 if (cmd == SIOCCHGTUNNEL) {
675 t->parms.iph.ttl = p.iph.ttl;
676 t->parms.iph.tos = p.iph.tos;
677 t->parms.iph.frag_off = p.iph.frag_off;
678 if (t->parms.link != p.link) {
679 t->parms.link = p.link;
680 ipip_tunnel_bind_dev(dev);
681 netdev_state_change(dev);
682 }
683 }
684 if (copy_to_user(ifr->ifr_ifru.ifru_data, &t->parms, sizeof(p)))
685 err = -EFAULT;
686 } else
687 err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
688 break;
689
690 case SIOCDELTUNNEL:
691 err = -EPERM;
692 if (!capable(CAP_NET_ADMIN))
693 goto done;
694
695 if (dev == ipn->fb_tunnel_dev) {
696 err = -EFAULT;
697 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
698 goto done;
699 err = -ENOENT;
700 if ((t = ipip_tunnel_locate(net, &p, 0)) == NULL)
701 goto done;
702 err = -EPERM;
703 if (t->dev == ipn->fb_tunnel_dev)
704 goto done;
705 dev = t->dev;
706 }
707 unregister_netdevice(dev);
708 err = 0;
709 break;
710
711 default:
712 err = -EINVAL;
713 }
714
715done:
716 return err;
717}
718
719static int ipip_tunnel_change_mtu(struct net_device *dev, int new_mtu)
720{
721 if (new_mtu < 68 || new_mtu > 0xFFF8 - sizeof(struct iphdr))
722 return -EINVAL;
723 dev->mtu = new_mtu;
724 return 0;
725}
726
727static const struct net_device_ops ipip_netdev_ops = {
728 .ndo_uninit = ipip_tunnel_uninit,
729 .ndo_start_xmit = ipip_tunnel_xmit,
730 .ndo_do_ioctl = ipip_tunnel_ioctl,
731 .ndo_change_mtu = ipip_tunnel_change_mtu,
732 .ndo_get_stats = ipip_get_stats,
733};
734
735static void ipip_dev_free(struct net_device *dev)
736{
737 free_percpu(dev->tstats);
738 free_netdev(dev);
739}
740
741static void ipip_tunnel_setup(struct net_device *dev)
742{
743 dev->netdev_ops = &ipip_netdev_ops;
744 dev->destructor = ipip_dev_free;
745
746 dev->type = ARPHRD_TUNNEL;
747 dev->hard_header_len = LL_MAX_HEADER + sizeof(struct iphdr);
748 dev->mtu = ETH_DATA_LEN - sizeof(struct iphdr);
749 dev->flags = IFF_NOARP;
750 dev->iflink = 0;
751 dev->addr_len = 4;
752 dev->features |= NETIF_F_NETNS_LOCAL;
753 dev->features |= NETIF_F_LLTX;
754 dev->priv_flags &= ~IFF_XMIT_DST_RELEASE;
755}
756
757static int ipip_tunnel_init(struct net_device *dev)
758{
759 struct ip_tunnel *tunnel = netdev_priv(dev);
760
761 tunnel->dev = dev;
762 strcpy(tunnel->parms.name, dev->name);
763
764 memcpy(dev->dev_addr, &tunnel->parms.iph.saddr, 4);
765 memcpy(dev->broadcast, &tunnel->parms.iph.daddr, 4);
766
767 ipip_tunnel_bind_dev(dev);
768
769 dev->tstats = alloc_percpu(struct pcpu_tstats);
770 if (!dev->tstats)
771 return -ENOMEM;
772
773 return 0;
774}
775
776static int __net_init ipip_fb_tunnel_init(struct net_device *dev)
777{
778 struct ip_tunnel *tunnel = netdev_priv(dev);
779 struct iphdr *iph = &tunnel->parms.iph;
780 struct ipip_net *ipn = net_generic(dev_net(dev), ipip_net_id);
781
782 tunnel->dev = dev;
783 strcpy(tunnel->parms.name, dev->name);
784
785 iph->version = 4;
786 iph->protocol = IPPROTO_IPIP;
787 iph->ihl = 5;
788
789 dev->tstats = alloc_percpu(struct pcpu_tstats);
790 if (!dev->tstats)
791 return -ENOMEM;
792
793 dev_hold(dev);
794 rcu_assign_pointer(ipn->tunnels_wc[0], tunnel);
795 return 0;
796}
797
798static struct xfrm_tunnel ipip_handler __read_mostly = {
799 .handler = ipip_rcv,
800 .err_handler = ipip_err,
801 .priority = 1,
802};
803
804static const char banner[] __initconst =
805 KERN_INFO "IPv4 over IPv4 tunneling driver\n";
806
807static void ipip_destroy_tunnels(struct ipip_net *ipn, struct list_head *head)
808{
809 int prio;
810
811 for (prio = 1; prio < 4; prio++) {
812 int h;
813 for (h = 0; h < HASH_SIZE; h++) {
814 struct ip_tunnel *t;
815
816 t = rtnl_dereference(ipn->tunnels[prio][h]);
817 while (t != NULL) {
818 unregister_netdevice_queue(t->dev, head);
819 t = rtnl_dereference(t->next);
820 }
821 }
822 }
823}
824
825static int __net_init ipip_init_net(struct net *net)
826{
827 struct ipip_net *ipn = net_generic(net, ipip_net_id);
828 int err;
829
830 ipn->tunnels[0] = ipn->tunnels_wc;
831 ipn->tunnels[1] = ipn->tunnels_l;
832 ipn->tunnels[2] = ipn->tunnels_r;
833 ipn->tunnels[3] = ipn->tunnels_r_l;
834
835 ipn->fb_tunnel_dev = alloc_netdev(sizeof(struct ip_tunnel),
836 "tunl0",
837 ipip_tunnel_setup);
838 if (!ipn->fb_tunnel_dev) {
839 err = -ENOMEM;
840 goto err_alloc_dev;
841 }
842 dev_net_set(ipn->fb_tunnel_dev, net);
843
844 err = ipip_fb_tunnel_init(ipn->fb_tunnel_dev);
845 if (err)
846 goto err_reg_dev;
847
848 if ((err = register_netdev(ipn->fb_tunnel_dev)))
849 goto err_reg_dev;
850
851 return 0;
852
853err_reg_dev:
854 ipip_dev_free(ipn->fb_tunnel_dev);
855err_alloc_dev:
856 /* nothing */
857 return err;
858}
859
860static void __net_exit ipip_exit_net(struct net *net)
861{
862 struct ipip_net *ipn = net_generic(net, ipip_net_id);
863 LIST_HEAD(list);
864
865 rtnl_lock();
866 ipip_destroy_tunnels(ipn, &list);
867 unregister_netdevice_queue(ipn->fb_tunnel_dev, &list);
868 unregister_netdevice_many(&list);
869 rtnl_unlock();
870}
871
872static struct pernet_operations ipip_net_ops = {
873 .init = ipip_init_net,
874 .exit = ipip_exit_net,
875 .id = &ipip_net_id,
876 .size = sizeof(struct ipip_net),
877};
878
879static int __init ipip_init(void)
880{
881 int err;
882
883 printk(banner);
884
885 err = register_pernet_device(&ipip_net_ops);
886 if (err < 0)
887 return err;
888 err = xfrm4_tunnel_register(&ipip_handler, AF_INET);
889 if (err < 0) {
890 unregister_pernet_device(&ipip_net_ops);
891 printk(KERN_INFO "ipip init: can't register tunnel\n");
892 }
893 return err;
894}
895
896static void __exit ipip_fini(void)
897{
898 if (xfrm4_tunnel_deregister(&ipip_handler, AF_INET))
899 printk(KERN_INFO "ipip close: can't deregister tunnel\n");
900
901 unregister_pernet_device(&ipip_net_ops);
902}
903
904module_init(ipip_init);
905module_exit(ipip_fini);
906MODULE_LICENSE("GPL");
907MODULE_ALIAS_NETDEV("tunl0");
1/*
2 * Linux NET3: IP/IP protocol decoder.
3 *
4 * Authors:
5 * Sam Lantinga (slouken@cs.ucdavis.edu) 02/01/95
6 *
7 * Fixes:
8 * Alan Cox : Merged and made usable non modular (its so tiny its silly as
9 * a module taking up 2 pages).
10 * Alan Cox : Fixed bug with 1.3.18 and IPIP not working (now needs to set skb->h.iph)
11 * to keep ip_forward happy.
12 * Alan Cox : More fixes for 1.3.21, and firewall fix. Maybe this will work soon 8).
13 * Kai Schulte : Fixed #defines for IP_FIREWALL->FIREWALL
14 * David Woodhouse : Perform some basic ICMP handling.
15 * IPIP Routing without decapsulation.
16 * Carlos Picoto : GRE over IP support
17 * Alexey Kuznetsov: Reworked. Really, now it is truncated version of ipv4/ip_gre.c.
18 * I do not want to merge them together.
19 *
20 * This program is free software; you can redistribute it and/or
21 * modify it under the terms of the GNU General Public License
22 * as published by the Free Software Foundation; either version
23 * 2 of the License, or (at your option) any later version.
24 *
25 */
26
27/* tunnel.c: an IP tunnel driver
28
29 The purpose of this driver is to provide an IP tunnel through
30 which you can tunnel network traffic transparently across subnets.
31
32 This was written by looking at Nick Holloway's dummy driver
33 Thanks for the great code!
34
35 -Sam Lantinga (slouken@cs.ucdavis.edu) 02/01/95
36
37 Minor tweaks:
38 Cleaned up the code a little and added some pre-1.3.0 tweaks.
39 dev->hard_header/hard_header_len changed to use no headers.
40 Comments/bracketing tweaked.
41 Made the tunnels use dev->name not tunnel: when error reporting.
42 Added tx_dropped stat
43
44 -Alan Cox (alan@lxorguk.ukuu.org.uk) 21 March 95
45
46 Reworked:
47 Changed to tunnel to destination gateway in addition to the
48 tunnel's pointopoint address
49 Almost completely rewritten
50 Note: There is currently no firewall or ICMP handling done.
51
52 -Sam Lantinga (slouken@cs.ucdavis.edu) 02/13/96
53
54*/
55
56/* Things I wish I had known when writing the tunnel driver:
57
58 When the tunnel_xmit() function is called, the skb contains the
59 packet to be sent (plus a great deal of extra info), and dev
60 contains the tunnel device that _we_ are.
61
62 When we are passed a packet, we are expected to fill in the
63 source address with our source IP address.
64
65 What is the proper way to allocate, copy and free a buffer?
66 After you allocate it, it is a "0 length" chunk of memory
67 starting at zero. If you want to add headers to the buffer
68 later, you'll have to call "skb_reserve(skb, amount)" with
69 the amount of memory you want reserved. Then, you call
70 "skb_put(skb, amount)" with the amount of space you want in
71 the buffer. skb_put() returns a pointer to the top (#0) of
72 that buffer. skb->len is set to the amount of space you have
73 "allocated" with skb_put(). You can then write up to skb->len
74 bytes to that buffer. If you need more, you can call skb_put()
75 again with the additional amount of space you need. You can
76 find out how much more space you can allocate by calling
77 "skb_tailroom(skb)".
78 Now, to add header space, call "skb_push(skb, header_len)".
79 This creates space at the beginning of the buffer and returns
80 a pointer to this new space. If later you need to strip a
81 header from a buffer, call "skb_pull(skb, header_len)".
82 skb_headroom() will return how much space is left at the top
83 of the buffer (before the main data). Remember, this headroom
84 space must be reserved before the skb_put() function is called.
85 */
86
87/*
88 This version of net/ipv4/ipip.c is cloned of net/ipv4/ip_gre.c
89
90 For comments look at net/ipv4/ip_gre.c --ANK
91 */
92
93
94#include <linux/capability.h>
95#include <linux/module.h>
96#include <linux/types.h>
97#include <linux/kernel.h>
98#include <linux/slab.h>
99#include <linux/uaccess.h>
100#include <linux/skbuff.h>
101#include <linux/netdevice.h>
102#include <linux/in.h>
103#include <linux/tcp.h>
104#include <linux/udp.h>
105#include <linux/if_arp.h>
106#include <linux/init.h>
107#include <linux/netfilter_ipv4.h>
108#include <linux/if_ether.h>
109
110#include <net/sock.h>
111#include <net/ip.h>
112#include <net/icmp.h>
113#include <net/ip_tunnels.h>
114#include <net/inet_ecn.h>
115#include <net/xfrm.h>
116#include <net/net_namespace.h>
117#include <net/netns/generic.h>
118#include <net/dst_metadata.h>
119
120static bool log_ecn_error = true;
121module_param(log_ecn_error, bool, 0644);
122MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN");
123
124static unsigned int ipip_net_id __read_mostly;
125
126static int ipip_tunnel_init(struct net_device *dev);
127static struct rtnl_link_ops ipip_link_ops __read_mostly;
128
129static int ipip_err(struct sk_buff *skb, u32 info)
130{
131
132/* All the routers (except for Linux) return only
133 8 bytes of packet payload. It means, that precise relaying of
134 ICMP in the real Internet is absolutely infeasible.
135 */
136 struct net *net = dev_net(skb->dev);
137 struct ip_tunnel_net *itn = net_generic(net, ipip_net_id);
138 const struct iphdr *iph = (const struct iphdr *)skb->data;
139 struct ip_tunnel *t;
140 int err;
141 const int type = icmp_hdr(skb)->type;
142 const int code = icmp_hdr(skb)->code;
143
144 err = -ENOENT;
145 t = ip_tunnel_lookup(itn, skb->dev->ifindex, TUNNEL_NO_KEY,
146 iph->daddr, iph->saddr, 0);
147 if (!t)
148 goto out;
149
150 if (type == ICMP_DEST_UNREACH && code == ICMP_FRAG_NEEDED) {
151 ipv4_update_pmtu(skb, dev_net(skb->dev), info,
152 t->parms.link, 0, iph->protocol, 0);
153 err = 0;
154 goto out;
155 }
156
157 if (type == ICMP_REDIRECT) {
158 ipv4_redirect(skb, dev_net(skb->dev), t->parms.link, 0,
159 iph->protocol, 0);
160 err = 0;
161 goto out;
162 }
163
164 if (t->parms.iph.daddr == 0)
165 goto out;
166
167 err = 0;
168 if (t->parms.iph.ttl == 0 && type == ICMP_TIME_EXCEEDED)
169 goto out;
170
171 if (time_before(jiffies, t->err_time + IPTUNNEL_ERR_TIMEO))
172 t->err_count++;
173 else
174 t->err_count = 1;
175 t->err_time = jiffies;
176
177out:
178 return err;
179}
180
181static const struct tnl_ptk_info ipip_tpi = {
182 /* no tunnel info required for ipip. */
183 .proto = htons(ETH_P_IP),
184};
185
186#if IS_ENABLED(CONFIG_MPLS)
187static const struct tnl_ptk_info mplsip_tpi = {
188 /* no tunnel info required for mplsip. */
189 .proto = htons(ETH_P_MPLS_UC),
190};
191#endif
192
193static int ipip_tunnel_rcv(struct sk_buff *skb, u8 ipproto)
194{
195 struct net *net = dev_net(skb->dev);
196 struct ip_tunnel_net *itn = net_generic(net, ipip_net_id);
197 struct metadata_dst *tun_dst = NULL;
198 struct ip_tunnel *tunnel;
199 const struct iphdr *iph;
200
201 iph = ip_hdr(skb);
202 tunnel = ip_tunnel_lookup(itn, skb->dev->ifindex, TUNNEL_NO_KEY,
203 iph->saddr, iph->daddr, 0);
204 if (tunnel) {
205 const struct tnl_ptk_info *tpi;
206
207 if (tunnel->parms.iph.protocol != ipproto &&
208 tunnel->parms.iph.protocol != 0)
209 goto drop;
210
211 if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb))
212 goto drop;
213#if IS_ENABLED(CONFIG_MPLS)
214 if (ipproto == IPPROTO_MPLS)
215 tpi = &mplsip_tpi;
216 else
217#endif
218 tpi = &ipip_tpi;
219 if (iptunnel_pull_header(skb, 0, tpi->proto, false))
220 goto drop;
221 if (tunnel->collect_md) {
222 tun_dst = ip_tun_rx_dst(skb, 0, 0, 0);
223 if (!tun_dst)
224 return 0;
225 }
226 return ip_tunnel_rcv(tunnel, skb, tpi, tun_dst, log_ecn_error);
227 }
228
229 return -1;
230
231drop:
232 kfree_skb(skb);
233 return 0;
234}
235
236static int ipip_rcv(struct sk_buff *skb)
237{
238 return ipip_tunnel_rcv(skb, IPPROTO_IPIP);
239}
240
241#if IS_ENABLED(CONFIG_MPLS)
242static int mplsip_rcv(struct sk_buff *skb)
243{
244 return ipip_tunnel_rcv(skb, IPPROTO_MPLS);
245}
246#endif
247
248/*
249 * This function assumes it is being called from dev_queue_xmit()
250 * and that skb is filled properly by that function.
251 */
252static netdev_tx_t ipip_tunnel_xmit(struct sk_buff *skb,
253 struct net_device *dev)
254{
255 struct ip_tunnel *tunnel = netdev_priv(dev);
256 const struct iphdr *tiph = &tunnel->parms.iph;
257 u8 ipproto;
258
259 switch (skb->protocol) {
260 case htons(ETH_P_IP):
261 ipproto = IPPROTO_IPIP;
262 break;
263#if IS_ENABLED(CONFIG_MPLS)
264 case htons(ETH_P_MPLS_UC):
265 ipproto = IPPROTO_MPLS;
266 break;
267#endif
268 default:
269 goto tx_error;
270 }
271
272 if (tiph->protocol != ipproto && tiph->protocol != 0)
273 goto tx_error;
274
275 if (iptunnel_handle_offloads(skb, SKB_GSO_IPXIP4))
276 goto tx_error;
277
278 skb_set_inner_ipproto(skb, ipproto);
279
280 if (tunnel->collect_md)
281 ip_md_tunnel_xmit(skb, dev, ipproto);
282 else
283 ip_tunnel_xmit(skb, dev, tiph, ipproto);
284 return NETDEV_TX_OK;
285
286tx_error:
287 kfree_skb(skb);
288
289 dev->stats.tx_errors++;
290 return NETDEV_TX_OK;
291}
292
293static bool ipip_tunnel_ioctl_verify_protocol(u8 ipproto)
294{
295 switch (ipproto) {
296 case 0:
297 case IPPROTO_IPIP:
298#if IS_ENABLED(CONFIG_MPLS)
299 case IPPROTO_MPLS:
300#endif
301 return true;
302 }
303
304 return false;
305}
306
307static int
308ipip_tunnel_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
309{
310 int err = 0;
311 struct ip_tunnel_parm p;
312
313 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
314 return -EFAULT;
315
316 if (cmd == SIOCADDTUNNEL || cmd == SIOCCHGTUNNEL) {
317 if (p.iph.version != 4 ||
318 !ipip_tunnel_ioctl_verify_protocol(p.iph.protocol) ||
319 p.iph.ihl != 5 || (p.iph.frag_off&htons(~IP_DF)))
320 return -EINVAL;
321 }
322
323 p.i_key = p.o_key = 0;
324 p.i_flags = p.o_flags = 0;
325 err = ip_tunnel_ioctl(dev, &p, cmd);
326 if (err)
327 return err;
328
329 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
330 return -EFAULT;
331
332 return 0;
333}
334
335static const struct net_device_ops ipip_netdev_ops = {
336 .ndo_init = ipip_tunnel_init,
337 .ndo_uninit = ip_tunnel_uninit,
338 .ndo_start_xmit = ipip_tunnel_xmit,
339 .ndo_do_ioctl = ipip_tunnel_ioctl,
340 .ndo_change_mtu = ip_tunnel_change_mtu,
341 .ndo_get_stats64 = ip_tunnel_get_stats64,
342 .ndo_get_iflink = ip_tunnel_get_iflink,
343};
344
345#define IPIP_FEATURES (NETIF_F_SG | \
346 NETIF_F_FRAGLIST | \
347 NETIF_F_HIGHDMA | \
348 NETIF_F_GSO_SOFTWARE | \
349 NETIF_F_HW_CSUM)
350
351static void ipip_tunnel_setup(struct net_device *dev)
352{
353 dev->netdev_ops = &ipip_netdev_ops;
354
355 dev->type = ARPHRD_TUNNEL;
356 dev->flags = IFF_NOARP;
357 dev->addr_len = 4;
358 dev->features |= NETIF_F_LLTX;
359 netif_keep_dst(dev);
360
361 dev->features |= IPIP_FEATURES;
362 dev->hw_features |= IPIP_FEATURES;
363 ip_tunnel_setup(dev, ipip_net_id);
364}
365
366static int ipip_tunnel_init(struct net_device *dev)
367{
368 struct ip_tunnel *tunnel = netdev_priv(dev);
369
370 memcpy(dev->dev_addr, &tunnel->parms.iph.saddr, 4);
371 memcpy(dev->broadcast, &tunnel->parms.iph.daddr, 4);
372
373 tunnel->tun_hlen = 0;
374 tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen;
375 return ip_tunnel_init(dev);
376}
377
378static int ipip_tunnel_validate(struct nlattr *tb[], struct nlattr *data[])
379{
380 u8 proto;
381
382 if (!data || !data[IFLA_IPTUN_PROTO])
383 return 0;
384
385 proto = nla_get_u8(data[IFLA_IPTUN_PROTO]);
386 if (proto != IPPROTO_IPIP && proto != IPPROTO_MPLS && proto != 0)
387 return -EINVAL;
388
389 return 0;
390}
391
392static void ipip_netlink_parms(struct nlattr *data[],
393 struct ip_tunnel_parm *parms, bool *collect_md)
394{
395 memset(parms, 0, sizeof(*parms));
396
397 parms->iph.version = 4;
398 parms->iph.protocol = IPPROTO_IPIP;
399 parms->iph.ihl = 5;
400 *collect_md = false;
401
402 if (!data)
403 return;
404
405 if (data[IFLA_IPTUN_LINK])
406 parms->link = nla_get_u32(data[IFLA_IPTUN_LINK]);
407
408 if (data[IFLA_IPTUN_LOCAL])
409 parms->iph.saddr = nla_get_in_addr(data[IFLA_IPTUN_LOCAL]);
410
411 if (data[IFLA_IPTUN_REMOTE])
412 parms->iph.daddr = nla_get_in_addr(data[IFLA_IPTUN_REMOTE]);
413
414 if (data[IFLA_IPTUN_TTL]) {
415 parms->iph.ttl = nla_get_u8(data[IFLA_IPTUN_TTL]);
416 if (parms->iph.ttl)
417 parms->iph.frag_off = htons(IP_DF);
418 }
419
420 if (data[IFLA_IPTUN_TOS])
421 parms->iph.tos = nla_get_u8(data[IFLA_IPTUN_TOS]);
422
423 if (data[IFLA_IPTUN_PROTO])
424 parms->iph.protocol = nla_get_u8(data[IFLA_IPTUN_PROTO]);
425
426 if (!data[IFLA_IPTUN_PMTUDISC] || nla_get_u8(data[IFLA_IPTUN_PMTUDISC]))
427 parms->iph.frag_off = htons(IP_DF);
428
429 if (data[IFLA_IPTUN_COLLECT_METADATA])
430 *collect_md = true;
431}
432
433/* This function returns true when ENCAP attributes are present in the nl msg */
434static bool ipip_netlink_encap_parms(struct nlattr *data[],
435 struct ip_tunnel_encap *ipencap)
436{
437 bool ret = false;
438
439 memset(ipencap, 0, sizeof(*ipencap));
440
441 if (!data)
442 return ret;
443
444 if (data[IFLA_IPTUN_ENCAP_TYPE]) {
445 ret = true;
446 ipencap->type = nla_get_u16(data[IFLA_IPTUN_ENCAP_TYPE]);
447 }
448
449 if (data[IFLA_IPTUN_ENCAP_FLAGS]) {
450 ret = true;
451 ipencap->flags = nla_get_u16(data[IFLA_IPTUN_ENCAP_FLAGS]);
452 }
453
454 if (data[IFLA_IPTUN_ENCAP_SPORT]) {
455 ret = true;
456 ipencap->sport = nla_get_be16(data[IFLA_IPTUN_ENCAP_SPORT]);
457 }
458
459 if (data[IFLA_IPTUN_ENCAP_DPORT]) {
460 ret = true;
461 ipencap->dport = nla_get_be16(data[IFLA_IPTUN_ENCAP_DPORT]);
462 }
463
464 return ret;
465}
466
467static int ipip_newlink(struct net *src_net, struct net_device *dev,
468 struct nlattr *tb[], struct nlattr *data[])
469{
470 struct ip_tunnel *t = netdev_priv(dev);
471 struct ip_tunnel_parm p;
472 struct ip_tunnel_encap ipencap;
473
474 if (ipip_netlink_encap_parms(data, &ipencap)) {
475 int err = ip_tunnel_encap_setup(t, &ipencap);
476
477 if (err < 0)
478 return err;
479 }
480
481 ipip_netlink_parms(data, &p, &t->collect_md);
482 return ip_tunnel_newlink(dev, tb, &p);
483}
484
485static int ipip_changelink(struct net_device *dev, struct nlattr *tb[],
486 struct nlattr *data[])
487{
488 struct ip_tunnel_parm p;
489 struct ip_tunnel_encap ipencap;
490 bool collect_md;
491
492 if (ipip_netlink_encap_parms(data, &ipencap)) {
493 struct ip_tunnel *t = netdev_priv(dev);
494 int err = ip_tunnel_encap_setup(t, &ipencap);
495
496 if (err < 0)
497 return err;
498 }
499
500 ipip_netlink_parms(data, &p, &collect_md);
501 if (collect_md)
502 return -EINVAL;
503
504 if (((dev->flags & IFF_POINTOPOINT) && !p.iph.daddr) ||
505 (!(dev->flags & IFF_POINTOPOINT) && p.iph.daddr))
506 return -EINVAL;
507
508 return ip_tunnel_changelink(dev, tb, &p);
509}
510
511static size_t ipip_get_size(const struct net_device *dev)
512{
513 return
514 /* IFLA_IPTUN_LINK */
515 nla_total_size(4) +
516 /* IFLA_IPTUN_LOCAL */
517 nla_total_size(4) +
518 /* IFLA_IPTUN_REMOTE */
519 nla_total_size(4) +
520 /* IFLA_IPTUN_TTL */
521 nla_total_size(1) +
522 /* IFLA_IPTUN_TOS */
523 nla_total_size(1) +
524 /* IFLA_IPTUN_PROTO */
525 nla_total_size(1) +
526 /* IFLA_IPTUN_PMTUDISC */
527 nla_total_size(1) +
528 /* IFLA_IPTUN_ENCAP_TYPE */
529 nla_total_size(2) +
530 /* IFLA_IPTUN_ENCAP_FLAGS */
531 nla_total_size(2) +
532 /* IFLA_IPTUN_ENCAP_SPORT */
533 nla_total_size(2) +
534 /* IFLA_IPTUN_ENCAP_DPORT */
535 nla_total_size(2) +
536 /* IFLA_IPTUN_COLLECT_METADATA */
537 nla_total_size(0) +
538 0;
539}
540
541static int ipip_fill_info(struct sk_buff *skb, const struct net_device *dev)
542{
543 struct ip_tunnel *tunnel = netdev_priv(dev);
544 struct ip_tunnel_parm *parm = &tunnel->parms;
545
546 if (nla_put_u32(skb, IFLA_IPTUN_LINK, parm->link) ||
547 nla_put_in_addr(skb, IFLA_IPTUN_LOCAL, parm->iph.saddr) ||
548 nla_put_in_addr(skb, IFLA_IPTUN_REMOTE, parm->iph.daddr) ||
549 nla_put_u8(skb, IFLA_IPTUN_TTL, parm->iph.ttl) ||
550 nla_put_u8(skb, IFLA_IPTUN_TOS, parm->iph.tos) ||
551 nla_put_u8(skb, IFLA_IPTUN_PROTO, parm->iph.protocol) ||
552 nla_put_u8(skb, IFLA_IPTUN_PMTUDISC,
553 !!(parm->iph.frag_off & htons(IP_DF))))
554 goto nla_put_failure;
555
556 if (nla_put_u16(skb, IFLA_IPTUN_ENCAP_TYPE,
557 tunnel->encap.type) ||
558 nla_put_be16(skb, IFLA_IPTUN_ENCAP_SPORT,
559 tunnel->encap.sport) ||
560 nla_put_be16(skb, IFLA_IPTUN_ENCAP_DPORT,
561 tunnel->encap.dport) ||
562 nla_put_u16(skb, IFLA_IPTUN_ENCAP_FLAGS,
563 tunnel->encap.flags))
564 goto nla_put_failure;
565
566 if (tunnel->collect_md)
567 if (nla_put_flag(skb, IFLA_IPTUN_COLLECT_METADATA))
568 goto nla_put_failure;
569 return 0;
570
571nla_put_failure:
572 return -EMSGSIZE;
573}
574
575static const struct nla_policy ipip_policy[IFLA_IPTUN_MAX + 1] = {
576 [IFLA_IPTUN_LINK] = { .type = NLA_U32 },
577 [IFLA_IPTUN_LOCAL] = { .type = NLA_U32 },
578 [IFLA_IPTUN_REMOTE] = { .type = NLA_U32 },
579 [IFLA_IPTUN_TTL] = { .type = NLA_U8 },
580 [IFLA_IPTUN_TOS] = { .type = NLA_U8 },
581 [IFLA_IPTUN_PROTO] = { .type = NLA_U8 },
582 [IFLA_IPTUN_PMTUDISC] = { .type = NLA_U8 },
583 [IFLA_IPTUN_ENCAP_TYPE] = { .type = NLA_U16 },
584 [IFLA_IPTUN_ENCAP_FLAGS] = { .type = NLA_U16 },
585 [IFLA_IPTUN_ENCAP_SPORT] = { .type = NLA_U16 },
586 [IFLA_IPTUN_ENCAP_DPORT] = { .type = NLA_U16 },
587 [IFLA_IPTUN_COLLECT_METADATA] = { .type = NLA_FLAG },
588};
589
590static struct rtnl_link_ops ipip_link_ops __read_mostly = {
591 .kind = "ipip",
592 .maxtype = IFLA_IPTUN_MAX,
593 .policy = ipip_policy,
594 .priv_size = sizeof(struct ip_tunnel),
595 .setup = ipip_tunnel_setup,
596 .validate = ipip_tunnel_validate,
597 .newlink = ipip_newlink,
598 .changelink = ipip_changelink,
599 .dellink = ip_tunnel_dellink,
600 .get_size = ipip_get_size,
601 .fill_info = ipip_fill_info,
602 .get_link_net = ip_tunnel_get_link_net,
603};
604
605static struct xfrm_tunnel ipip_handler __read_mostly = {
606 .handler = ipip_rcv,
607 .err_handler = ipip_err,
608 .priority = 1,
609};
610
611#if IS_ENABLED(CONFIG_MPLS)
612static struct xfrm_tunnel mplsip_handler __read_mostly = {
613 .handler = mplsip_rcv,
614 .err_handler = ipip_err,
615 .priority = 1,
616};
617#endif
618
619static int __net_init ipip_init_net(struct net *net)
620{
621 return ip_tunnel_init_net(net, ipip_net_id, &ipip_link_ops, "tunl0");
622}
623
624static void __net_exit ipip_exit_net(struct net *net)
625{
626 struct ip_tunnel_net *itn = net_generic(net, ipip_net_id);
627 ip_tunnel_delete_net(itn, &ipip_link_ops);
628}
629
630static struct pernet_operations ipip_net_ops = {
631 .init = ipip_init_net,
632 .exit = ipip_exit_net,
633 .id = &ipip_net_id,
634 .size = sizeof(struct ip_tunnel_net),
635};
636
637static int __init ipip_init(void)
638{
639 int err;
640
641 pr_info("ipip: IPv4 and MPLS over IPv4 tunneling driver\n");
642
643 err = register_pernet_device(&ipip_net_ops);
644 if (err < 0)
645 return err;
646 err = xfrm4_tunnel_register(&ipip_handler, AF_INET);
647 if (err < 0) {
648 pr_info("%s: can't register tunnel\n", __func__);
649 goto xfrm_tunnel_ipip_failed;
650 }
651#if IS_ENABLED(CONFIG_MPLS)
652 err = xfrm4_tunnel_register(&mplsip_handler, AF_MPLS);
653 if (err < 0) {
654 pr_info("%s: can't register tunnel\n", __func__);
655 goto xfrm_tunnel_mplsip_failed;
656 }
657#endif
658 err = rtnl_link_register(&ipip_link_ops);
659 if (err < 0)
660 goto rtnl_link_failed;
661
662out:
663 return err;
664
665rtnl_link_failed:
666#if IS_ENABLED(CONFIG_MPLS)
667 xfrm4_tunnel_deregister(&mplsip_handler, AF_INET);
668xfrm_tunnel_mplsip_failed:
669
670#endif
671 xfrm4_tunnel_deregister(&ipip_handler, AF_INET);
672xfrm_tunnel_ipip_failed:
673 unregister_pernet_device(&ipip_net_ops);
674 goto out;
675}
676
677static void __exit ipip_fini(void)
678{
679 rtnl_link_unregister(&ipip_link_ops);
680 if (xfrm4_tunnel_deregister(&ipip_handler, AF_INET))
681 pr_info("%s: can't deregister tunnel\n", __func__);
682#if IS_ENABLED(CONFIG_MPLS)
683 if (xfrm4_tunnel_deregister(&mplsip_handler, AF_MPLS))
684 pr_info("%s: can't deregister tunnel\n", __func__);
685#endif
686 unregister_pernet_device(&ipip_net_ops);
687}
688
689module_init(ipip_init);
690module_exit(ipip_fini);
691MODULE_LICENSE("GPL");
692MODULE_ALIAS_RTNL_LINK("ipip");
693MODULE_ALIAS_NETDEV("tunl0");