blob: ae40ed1ba560df7296b6178ccd7e4d62499bc94e [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +09002 * Linux NET3: IP/IP protocol decoder.
Linus Torvalds1da177e2005-04-16 15:20:36 -07003 *
Linus Torvalds1da177e2005-04-16 15:20:36 -07004 * 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
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +090036
Linus Torvalds1da177e2005-04-16 15:20:36 -070037 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
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +090043
Alan Cox113aa832008-10-13 19:01:08 -070044 -Alan Cox (alan@lxorguk.ukuu.org.uk) 21 March 95
Linus Torvalds1da177e2005-04-16 15:20:36 -070045
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
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +090053
Linus Torvalds1da177e2005-04-16 15:20:36 -070054*/
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
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +090076 find out how much more space you can allocate by calling
Linus Torvalds1da177e2005-04-16 15:20:36 -070077 "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
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +090093
Randy Dunlap4fc268d2006-01-11 12:17:47 -080094#include <linux/capability.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070095#include <linux/module.h>
96#include <linux/types.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070097#include <linux/kernel.h>
98#include <asm/uaccess.h>
99#include <linux/skbuff.h>
100#include <linux/netdevice.h>
101#include <linux/in.h>
102#include <linux/tcp.h>
103#include <linux/udp.h>
104#include <linux/if_arp.h>
105#include <linux/mroute.h>
106#include <linux/init.h>
107#include <linux/netfilter_ipv4.h>
Kris Katterjohn46f25df2006-01-05 16:35:42 -0800108#include <linux/if_ether.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -0700109
110#include <net/sock.h>
111#include <net/ip.h>
112#include <net/icmp.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -0700113#include <net/ipip.h>
114#include <net/inet_ecn.h>
115#include <net/xfrm.h>
Pavel Emelyanov10dc4c72008-04-16 01:03:13 -0700116#include <net/net_namespace.h>
117#include <net/netns/generic.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -0700118
119#define HASH_SIZE 16
Al Virod5a0a1e2006-11-08 00:23:14 -0800120#define HASH(addr) (((__force u32)addr^((__force u32)addr>>4))&0xF)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700121
Pavel Emelyanov10dc4c72008-04-16 01:03:13 -0700122static int ipip_net_id;
123struct ipip_net {
Pavel Emelyanov44d3c292008-04-16 01:05:32 -0700124 struct ip_tunnel *tunnels_r_l[HASH_SIZE];
125 struct ip_tunnel *tunnels_r[HASH_SIZE];
126 struct ip_tunnel *tunnels_l[HASH_SIZE];
127 struct ip_tunnel *tunnels_wc[1];
128 struct ip_tunnel **tunnels[4];
129
Pavel Emelyanovb9855c52008-04-16 01:04:13 -0700130 struct net_device *fb_tunnel_dev;
Pavel Emelyanov10dc4c72008-04-16 01:03:13 -0700131};
132
Stephen Hemminger23a12b12008-11-20 20:33:21 -0800133static void ipip_fb_tunnel_init(struct net_device *dev);
134static void ipip_tunnel_init(struct net_device *dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700135static void ipip_tunnel_setup(struct net_device *dev);
136
Linus Torvalds1da177e2005-04-16 15:20:36 -0700137static DEFINE_RWLOCK(ipip_lock);
138
Pavel Emelyanovb9fae5c2008-04-16 01:04:35 -0700139static struct ip_tunnel * ipip_tunnel_lookup(struct net *net,
140 __be32 remote, __be32 local)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700141{
142 unsigned h0 = HASH(remote);
143 unsigned h1 = HASH(local);
144 struct ip_tunnel *t;
Pavel Emelyanov44d3c292008-04-16 01:05:32 -0700145 struct ipip_net *ipn = net_generic(net, ipip_net_id);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700146
Pavel Emelyanov44d3c292008-04-16 01:05:32 -0700147 for (t = ipn->tunnels_r_l[h0^h1]; t; t = t->next) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700148 if (local == t->parms.iph.saddr &&
149 remote == t->parms.iph.daddr && (t->dev->flags&IFF_UP))
150 return t;
151 }
Pavel Emelyanov44d3c292008-04-16 01:05:32 -0700152 for (t = ipn->tunnels_r[h0]; t; t = t->next) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700153 if (remote == t->parms.iph.daddr && (t->dev->flags&IFF_UP))
154 return t;
155 }
Pavel Emelyanov44d3c292008-04-16 01:05:32 -0700156 for (t = ipn->tunnels_l[h1]; t; t = t->next) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700157 if (local == t->parms.iph.saddr && (t->dev->flags&IFF_UP))
158 return t;
159 }
Pavel Emelyanov44d3c292008-04-16 01:05:32 -0700160 if ((t = ipn->tunnels_wc[0]) != NULL && (t->dev->flags&IFF_UP))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700161 return t;
162 return NULL;
163}
164
Pavel Emelyanovb9fae5c2008-04-16 01:04:35 -0700165static struct ip_tunnel **__ipip_bucket(struct ipip_net *ipn,
166 struct ip_tunnel_parm *parms)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700167{
YOSHIFUJI Hideaki87d1a162007-04-24 20:44:47 +0900168 __be32 remote = parms->iph.daddr;
169 __be32 local = parms->iph.saddr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700170 unsigned h = 0;
171 int prio = 0;
172
173 if (remote) {
174 prio |= 2;
175 h ^= HASH(remote);
176 }
177 if (local) {
178 prio |= 1;
179 h ^= HASH(local);
180 }
Pavel Emelyanov44d3c292008-04-16 01:05:32 -0700181 return &ipn->tunnels[prio][h];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700182}
183
Pavel Emelyanovb9fae5c2008-04-16 01:04:35 -0700184static inline struct ip_tunnel **ipip_bucket(struct ipip_net *ipn,
185 struct ip_tunnel *t)
YOSHIFUJI Hideaki87d1a162007-04-24 20:44:47 +0900186{
Pavel Emelyanovb9fae5c2008-04-16 01:04:35 -0700187 return __ipip_bucket(ipn, &t->parms);
YOSHIFUJI Hideaki87d1a162007-04-24 20:44:47 +0900188}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700189
Pavel Emelyanovb9fae5c2008-04-16 01:04:35 -0700190static void ipip_tunnel_unlink(struct ipip_net *ipn, struct ip_tunnel *t)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700191{
192 struct ip_tunnel **tp;
193
Pavel Emelyanovb9fae5c2008-04-16 01:04:35 -0700194 for (tp = ipip_bucket(ipn, t); *tp; tp = &(*tp)->next) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700195 if (t == *tp) {
196 write_lock_bh(&ipip_lock);
197 *tp = t->next;
198 write_unlock_bh(&ipip_lock);
199 break;
200 }
201 }
202}
203
Pavel Emelyanovb9fae5c2008-04-16 01:04:35 -0700204static void ipip_tunnel_link(struct ipip_net *ipn, struct ip_tunnel *t)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700205{
Pavel Emelyanovb9fae5c2008-04-16 01:04:35 -0700206 struct ip_tunnel **tp = ipip_bucket(ipn, t);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700207
208 t->next = *tp;
209 write_lock_bh(&ipip_lock);
210 *tp = t;
211 write_unlock_bh(&ipip_lock);
212}
213
Pavel Emelyanovb9fae5c2008-04-16 01:04:35 -0700214static struct ip_tunnel * ipip_tunnel_locate(struct net *net,
215 struct ip_tunnel_parm *parms, int create)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700216{
Al Virod5a0a1e2006-11-08 00:23:14 -0800217 __be32 remote = parms->iph.daddr;
218 __be32 local = parms->iph.saddr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700219 struct ip_tunnel *t, **tp, *nt;
220 struct net_device *dev;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700221 char name[IFNAMSIZ];
Pavel Emelyanovb9fae5c2008-04-16 01:04:35 -0700222 struct ipip_net *ipn = net_generic(net, ipip_net_id);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700223
Pavel Emelyanovb9fae5c2008-04-16 01:04:35 -0700224 for (tp = __ipip_bucket(ipn, parms); (t = *tp) != NULL; tp = &t->next) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700225 if (local == t->parms.iph.saddr && remote == t->parms.iph.daddr)
226 return t;
227 }
228 if (!create)
229 return NULL;
230
231 if (parms->name[0])
232 strlcpy(name, parms->name, IFNAMSIZ);
Pavel Emelyanov34cc7ba2008-02-23 20:19:20 -0800233 else
234 sprintf(name, "tunl%%d");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700235
236 dev = alloc_netdev(sizeof(*t), name, ipip_tunnel_setup);
237 if (dev == NULL)
238 return NULL;
239
Pavel Emelyanov0a826402008-04-16 01:06:18 -0700240 dev_net_set(dev, net);
241
Pavel Emelyanovb37d428b2008-02-26 23:51:04 -0800242 if (strchr(name, '%')) {
243 if (dev_alloc_name(dev, name) < 0)
244 goto failed_free;
245 }
246
Patrick McHardy2941a482006-01-08 22:05:26 -0800247 nt = netdev_priv(dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700248 nt->parms = *parms;
249
Stephen Hemminger23a12b12008-11-20 20:33:21 -0800250 ipip_tunnel_init(dev);
251
Pavel Emelyanovb37d428b2008-02-26 23:51:04 -0800252 if (register_netdevice(dev) < 0)
253 goto failed_free;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700254
255 dev_hold(dev);
Pavel Emelyanovb9fae5c2008-04-16 01:04:35 -0700256 ipip_tunnel_link(ipn, nt);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700257 return nt;
258
Pavel Emelyanovb37d428b2008-02-26 23:51:04 -0800259failed_free:
260 free_netdev(dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700261 return NULL;
262}
263
264static void ipip_tunnel_uninit(struct net_device *dev)
265{
Pavel Emelyanovb9855c52008-04-16 01:04:13 -0700266 struct net *net = dev_net(dev);
267 struct ipip_net *ipn = net_generic(net, ipip_net_id);
268
269 if (dev == ipn->fb_tunnel_dev) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700270 write_lock_bh(&ipip_lock);
Pavel Emelyanov44d3c292008-04-16 01:05:32 -0700271 ipn->tunnels_wc[0] = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700272 write_unlock_bh(&ipip_lock);
273 } else
Pavel Emelyanovb9fae5c2008-04-16 01:04:35 -0700274 ipip_tunnel_unlink(ipn, netdev_priv(dev));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700275 dev_put(dev);
276}
277
Herbert Xud2acc342006-03-28 01:12:13 -0800278static int ipip_err(struct sk_buff *skb, u32 info)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700279{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700280
Rami Rosen071f92d2008-05-21 17:47:54 -0700281/* All the routers (except for Linux) return only
Linus Torvalds1da177e2005-04-16 15:20:36 -0700282 8 bytes of packet payload. It means, that precise relaying of
283 ICMP in the real Internet is absolutely infeasible.
284 */
Jianjun Kong5a5f3a82008-11-03 00:24:34 -0800285 struct iphdr *iph = (struct iphdr *)skb->data;
Arnaldo Carvalho de Melo88c76642007-03-13 14:43:18 -0300286 const int type = icmp_hdr(skb)->type;
287 const int code = icmp_hdr(skb)->code;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700288 struct ip_tunnel *t;
Herbert Xud2acc342006-03-28 01:12:13 -0800289 int err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700290
291 switch (type) {
292 default:
293 case ICMP_PARAMETERPROB:
Herbert Xud2acc342006-03-28 01:12:13 -0800294 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700295
296 case ICMP_DEST_UNREACH:
297 switch (code) {
298 case ICMP_SR_FAILED:
299 case ICMP_PORT_UNREACH:
300 /* Impossible event. */
Herbert Xud2acc342006-03-28 01:12:13 -0800301 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700302 case ICMP_FRAG_NEEDED:
303 /* Soft state for pmtu is maintained by IP core. */
Herbert Xud2acc342006-03-28 01:12:13 -0800304 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700305 default:
306 /* All others are translated to HOST_UNREACH.
307 rfc2003 contains "deep thoughts" about NET_UNREACH,
308 I believe they are just ether pollution. --ANK
309 */
310 break;
311 }
312 break;
313 case ICMP_TIME_EXCEEDED:
314 if (code != ICMP_EXC_TTL)
Herbert Xud2acc342006-03-28 01:12:13 -0800315 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700316 break;
317 }
318
Herbert Xud2acc342006-03-28 01:12:13 -0800319 err = -ENOENT;
320
Linus Torvalds1da177e2005-04-16 15:20:36 -0700321 read_lock(&ipip_lock);
Pavel Emelyanovcec3ffa2008-04-16 01:05:03 -0700322 t = ipip_tunnel_lookup(dev_net(skb->dev), iph->daddr, iph->saddr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700323 if (t == NULL || t->parms.iph.daddr == 0)
324 goto out;
Herbert Xud2acc342006-03-28 01:12:13 -0800325
326 err = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700327 if (t->parms.iph.ttl == 0 && type == ICMP_TIME_EXCEEDED)
328 goto out;
329
Wei Yongjun26d94b42009-02-24 23:36:47 -0800330 if (time_before(jiffies, t->err_time + IPTUNNEL_ERR_TIMEO))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700331 t->err_count++;
332 else
333 t->err_count = 1;
334 t->err_time = jiffies;
335out:
336 read_unlock(&ipip_lock);
Herbert Xud2acc342006-03-28 01:12:13 -0800337 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700338}
339
Arnaldo Carvalho de Meloeddc9ec2007-04-20 22:47:35 -0700340static inline void ipip_ecn_decapsulate(const struct iphdr *outer_iph,
341 struct sk_buff *skb)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700342{
Arnaldo Carvalho de Meloeddc9ec2007-04-20 22:47:35 -0700343 struct iphdr *inner_iph = ip_hdr(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700344
345 if (INET_ECN_is_ce(outer_iph->tos))
346 IP_ECN_set_ce(inner_iph);
347}
348
349static int ipip_rcv(struct sk_buff *skb)
350{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700351 struct ip_tunnel *tunnel;
Arnaldo Carvalho de Meloeddc9ec2007-04-20 22:47:35 -0700352 const struct iphdr *iph = ip_hdr(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700353
354 read_lock(&ipip_lock);
Pavel Emelyanovcec3ffa2008-04-16 01:05:03 -0700355 if ((tunnel = ipip_tunnel_lookup(dev_net(skb->dev),
Pavel Emelyanovb9fae5c2008-04-16 01:04:35 -0700356 iph->saddr, iph->daddr)) != NULL) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700357 if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb)) {
358 read_unlock(&ipip_lock);
359 kfree_skb(skb);
360 return 0;
361 }
362
363 secpath_reset(skb);
364
Arnaldo Carvalho de Melob0e380b2007-04-10 21:21:55 -0700365 skb->mac_header = skb->network_header;
Arnaldo Carvalho de Meloc1d2bbe2007-04-10 20:45:18 -0700366 skb_reset_network_header(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700367 skb->protocol = htons(ETH_P_IP);
368 skb->pkt_type = PACKET_HOST;
369
Pavel Emelyanov50f59ce2008-05-21 14:15:16 -0700370 tunnel->dev->stats.rx_packets++;
371 tunnel->dev->stats.rx_bytes += skb->len;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700372 skb->dev = tunnel->dev;
Eric Dumazetadf30902009-06-02 05:19:30 +0000373 skb_dst_drop(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700374 nf_reset(skb);
375 ipip_ecn_decapsulate(iph, skb);
376 netif_rx(skb);
377 read_unlock(&ipip_lock);
378 return 0;
379 }
380 read_unlock(&ipip_lock);
381
Linus Torvalds1da177e2005-04-16 15:20:36 -0700382 return -1;
383}
384
385/*
386 * This function assumes it is being called from dev_queue_xmit()
387 * and that skb is filled properly by that function.
388 */
389
Stephen Hemminger6fef4c02009-08-31 19:50:41 +0000390static netdev_tx_t ipip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700391{
Patrick McHardy2941a482006-01-08 22:05:26 -0800392 struct ip_tunnel *tunnel = netdev_priv(dev);
Pavel Emelyanov50f59ce2008-05-21 14:15:16 -0700393 struct net_device_stats *stats = &tunnel->dev->stats;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700394 struct iphdr *tiph = &tunnel->parms.iph;
395 u8 tos = tunnel->parms.iph.tos;
Al Virod5a0a1e2006-11-08 00:23:14 -0800396 __be16 df = tiph->frag_off;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700397 struct rtable *rt; /* Route to the other host */
398 struct net_device *tdev; /* Device to other host */
Arnaldo Carvalho de Meloeddc9ec2007-04-20 22:47:35 -0700399 struct iphdr *old_iph = ip_hdr(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700400 struct iphdr *iph; /* Our new IP header */
Chuck Leverc2636b42007-10-23 21:07:32 -0700401 unsigned int max_headroom; /* The extra header space needed */
Al Virod5a0a1e2006-11-08 00:23:14 -0800402 __be32 dst = tiph->daddr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700403 int mtu;
404
Linus Torvalds1da177e2005-04-16 15:20:36 -0700405 if (skb->protocol != htons(ETH_P_IP))
406 goto tx_error;
407
408 if (tos&1)
409 tos = old_iph->tos;
410
411 if (!dst) {
412 /* NBMA tunnel */
Eric Dumazet511c3f92009-06-02 05:14:27 +0000413 if ((rt = skb_rtable(skb)) == NULL) {
Pavel Emelyanov50f59ce2008-05-21 14:15:16 -0700414 stats->tx_fifo_errors++;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700415 goto tx_error;
416 }
417 if ((dst = rt->rt_gateway) == 0)
418 goto tx_error_icmp;
419 }
420
421 {
422 struct flowi fl = { .oif = tunnel->parms.link,
423 .nl_u = { .ip4_u =
424 { .daddr = dst,
425 .saddr = tiph->saddr,
426 .tos = RT_TOS(tos) } },
427 .proto = IPPROTO_IPIP };
Pavel Emelyanovb99f0152008-04-16 01:05:57 -0700428 if (ip_route_output_key(dev_net(dev), &rt, &fl)) {
Pavel Emelyanov50f59ce2008-05-21 14:15:16 -0700429 stats->tx_carrier_errors++;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700430 goto tx_error_icmp;
431 }
432 }
433 tdev = rt->u.dst.dev;
434
435 if (tdev == dev) {
436 ip_rt_put(rt);
Pavel Emelyanov50f59ce2008-05-21 14:15:16 -0700437 stats->collisions++;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700438 goto tx_error;
439 }
440
Herbert Xu23ca0c92009-11-06 10:37:41 +0000441 df |= old_iph->frag_off & htons(IP_DF);
442
443 if (df) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700444 mtu = dst_mtu(&rt->u.dst) - sizeof(struct iphdr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700445
Herbert Xu23ca0c92009-11-06 10:37:41 +0000446 if (mtu < 68) {
447 stats->collisions++;
448 ip_rt_put(rt);
449 goto tx_error;
450 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700451
Herbert Xu23ca0c92009-11-06 10:37:41 +0000452 if (skb_dst(skb))
453 skb_dst(skb)->ops->update_pmtu(skb_dst(skb), mtu);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700454
Herbert Xu23ca0c92009-11-06 10:37:41 +0000455 if ((old_iph->frag_off & htons(IP_DF)) &&
456 mtu < ntohs(old_iph->tot_len)) {
457 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
458 htonl(mtu));
459 ip_rt_put(rt);
460 goto tx_error;
461 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700462 }
463
464 if (tunnel->err_count > 0) {
Wei Yongjun26d94b42009-02-24 23:36:47 -0800465 if (time_before(jiffies,
466 tunnel->err_time + IPTUNNEL_ERR_TIMEO)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700467 tunnel->err_count--;
468 dst_link_failure(skb);
469 } else
470 tunnel->err_count = 0;
471 }
472
473 /*
474 * Okay, now see if we can stuff it in the buffer as-is.
475 */
476 max_headroom = (LL_RESERVED_SPACE(tdev)+sizeof(struct iphdr));
477
Patrick McHardycfbba492007-07-09 15:33:40 -0700478 if (skb_headroom(skb) < max_headroom || skb_shared(skb) ||
479 (skb_cloned(skb) && !skb_clone_writable(skb, 0))) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700480 struct sk_buff *new_skb = skb_realloc_headroom(skb, max_headroom);
481 if (!new_skb) {
482 ip_rt_put(rt);
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +0900483 stats->tx_dropped++;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700484 dev_kfree_skb(skb);
Patrick McHardy6ed10652009-06-23 06:03:08 +0000485 return NETDEV_TX_OK;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700486 }
487 if (skb->sk)
488 skb_set_owner_w(new_skb, skb->sk);
489 dev_kfree_skb(skb);
490 skb = new_skb;
Arnaldo Carvalho de Meloeddc9ec2007-04-20 22:47:35 -0700491 old_iph = ip_hdr(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700492 }
493
Arnaldo Carvalho de Melob0e380b2007-04-10 21:21:55 -0700494 skb->transport_header = skb->network_header;
Arnaldo Carvalho de Meloe2d1bca2007-04-10 20:46:21 -0700495 skb_push(skb, sizeof(struct iphdr));
496 skb_reset_network_header(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700497 memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
Patrick McHardy48d5cad2006-02-15 15:10:22 -0800498 IPCB(skb)->flags &= ~(IPSKB_XFRM_TUNNEL_SIZE | IPSKB_XFRM_TRANSFORMED |
499 IPSKB_REROUTED);
Eric Dumazetadf30902009-06-02 05:19:30 +0000500 skb_dst_drop(skb);
501 skb_dst_set(skb, &rt->u.dst);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700502
503 /*
504 * Push down and install the IPIP header.
505 */
506
Arnaldo Carvalho de Meloeddc9ec2007-04-20 22:47:35 -0700507 iph = ip_hdr(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700508 iph->version = 4;
509 iph->ihl = sizeof(struct iphdr)>>2;
510 iph->frag_off = df;
511 iph->protocol = IPPROTO_IPIP;
512 iph->tos = INET_ECN_encapsulate(tos, old_iph->tos);
513 iph->daddr = rt->rt_dst;
514 iph->saddr = rt->rt_src;
515
516 if ((iph->ttl = tiph->ttl) == 0)
517 iph->ttl = old_iph->ttl;
518
519 nf_reset(skb);
520
521 IPTUNNEL_XMIT();
Patrick McHardy6ed10652009-06-23 06:03:08 +0000522 return NETDEV_TX_OK;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700523
524tx_error_icmp:
525 dst_link_failure(skb);
526tx_error:
527 stats->tx_errors++;
528 dev_kfree_skb(skb);
Patrick McHardy6ed10652009-06-23 06:03:08 +0000529 return NETDEV_TX_OK;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700530}
531
Michal Schmidt55339952007-12-12 11:01:43 -0800532static void ipip_tunnel_bind_dev(struct net_device *dev)
533{
534 struct net_device *tdev = NULL;
535 struct ip_tunnel *tunnel;
536 struct iphdr *iph;
537
538 tunnel = netdev_priv(dev);
539 iph = &tunnel->parms.iph;
540
541 if (iph->daddr) {
542 struct flowi fl = { .oif = tunnel->parms.link,
543 .nl_u = { .ip4_u =
544 { .daddr = iph->daddr,
545 .saddr = iph->saddr,
546 .tos = RT_TOS(iph->tos) } },
547 .proto = IPPROTO_IPIP };
548 struct rtable *rt;
Pavel Emelyanovb99f0152008-04-16 01:05:57 -0700549 if (!ip_route_output_key(dev_net(dev), &rt, &fl)) {
Michal Schmidt55339952007-12-12 11:01:43 -0800550 tdev = rt->u.dst.dev;
551 ip_rt_put(rt);
552 }
553 dev->flags |= IFF_POINTOPOINT;
554 }
555
556 if (!tdev && tunnel->parms.link)
Pavel Emelyanovb99f0152008-04-16 01:05:57 -0700557 tdev = __dev_get_by_index(dev_net(dev), tunnel->parms.link);
Michal Schmidt55339952007-12-12 11:01:43 -0800558
559 if (tdev) {
560 dev->hard_header_len = tdev->hard_header_len + sizeof(struct iphdr);
561 dev->mtu = tdev->mtu - sizeof(struct iphdr);
562 }
563 dev->iflink = tunnel->parms.link;
564}
565
Linus Torvalds1da177e2005-04-16 15:20:36 -0700566static int
567ipip_tunnel_ioctl (struct net_device *dev, struct ifreq *ifr, int cmd)
568{
569 int err = 0;
570 struct ip_tunnel_parm p;
571 struct ip_tunnel *t;
Pavel Emelyanovb9855c52008-04-16 01:04:13 -0700572 struct net *net = dev_net(dev);
573 struct ipip_net *ipn = net_generic(net, ipip_net_id);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700574
575 switch (cmd) {
576 case SIOCGETTUNNEL:
577 t = NULL;
Pavel Emelyanovb9855c52008-04-16 01:04:13 -0700578 if (dev == ipn->fb_tunnel_dev) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700579 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) {
580 err = -EFAULT;
581 break;
582 }
Pavel Emelyanovb9fae5c2008-04-16 01:04:35 -0700583 t = ipip_tunnel_locate(net, &p, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700584 }
585 if (t == NULL)
Patrick McHardy2941a482006-01-08 22:05:26 -0800586 t = netdev_priv(dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700587 memcpy(&p, &t->parms, sizeof(p));
588 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
589 err = -EFAULT;
590 break;
591
592 case SIOCADDTUNNEL:
593 case SIOCCHGTUNNEL:
594 err = -EPERM;
595 if (!capable(CAP_NET_ADMIN))
596 goto done;
597
598 err = -EFAULT;
599 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
600 goto done;
601
602 err = -EINVAL;
603 if (p.iph.version != 4 || p.iph.protocol != IPPROTO_IPIP ||
604 p.iph.ihl != 5 || (p.iph.frag_off&htons(~IP_DF)))
605 goto done;
606 if (p.iph.ttl)
607 p.iph.frag_off |= htons(IP_DF);
608
Pavel Emelyanovb9fae5c2008-04-16 01:04:35 -0700609 t = ipip_tunnel_locate(net, &p, cmd == SIOCADDTUNNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700610
Pavel Emelyanovb9855c52008-04-16 01:04:13 -0700611 if (dev != ipn->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700612 if (t != NULL) {
613 if (t->dev != dev) {
614 err = -EEXIST;
615 break;
616 }
617 } else {
618 if (((dev->flags&IFF_POINTOPOINT) && !p.iph.daddr) ||
619 (!(dev->flags&IFF_POINTOPOINT) && p.iph.daddr)) {
620 err = -EINVAL;
621 break;
622 }
Patrick McHardy2941a482006-01-08 22:05:26 -0800623 t = netdev_priv(dev);
Pavel Emelyanovb9fae5c2008-04-16 01:04:35 -0700624 ipip_tunnel_unlink(ipn, t);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700625 t->parms.iph.saddr = p.iph.saddr;
626 t->parms.iph.daddr = p.iph.daddr;
627 memcpy(dev->dev_addr, &p.iph.saddr, 4);
628 memcpy(dev->broadcast, &p.iph.daddr, 4);
Pavel Emelyanovb9fae5c2008-04-16 01:04:35 -0700629 ipip_tunnel_link(ipn, t);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700630 netdev_state_change(dev);
631 }
632 }
633
634 if (t) {
635 err = 0;
636 if (cmd == SIOCCHGTUNNEL) {
637 t->parms.iph.ttl = p.iph.ttl;
638 t->parms.iph.tos = p.iph.tos;
639 t->parms.iph.frag_off = p.iph.frag_off;
Michal Schmidt55339952007-12-12 11:01:43 -0800640 if (t->parms.link != p.link) {
641 t->parms.link = p.link;
642 ipip_tunnel_bind_dev(dev);
643 netdev_state_change(dev);
644 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700645 }
646 if (copy_to_user(ifr->ifr_ifru.ifru_data, &t->parms, sizeof(p)))
647 err = -EFAULT;
648 } else
649 err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
650 break;
651
652 case SIOCDELTUNNEL:
653 err = -EPERM;
654 if (!capable(CAP_NET_ADMIN))
655 goto done;
656
Pavel Emelyanovb9855c52008-04-16 01:04:13 -0700657 if (dev == ipn->fb_tunnel_dev) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700658 err = -EFAULT;
659 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
660 goto done;
661 err = -ENOENT;
Pavel Emelyanovb9fae5c2008-04-16 01:04:35 -0700662 if ((t = ipip_tunnel_locate(net, &p, 0)) == NULL)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700663 goto done;
664 err = -EPERM;
Pavel Emelyanovb9855c52008-04-16 01:04:13 -0700665 if (t->dev == ipn->fb_tunnel_dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700666 goto done;
667 dev = t->dev;
668 }
Stephen Hemminger22f8cde2007-02-07 00:09:58 -0800669 unregister_netdevice(dev);
670 err = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700671 break;
672
673 default:
674 err = -EINVAL;
675 }
676
677done:
678 return err;
679}
680
Linus Torvalds1da177e2005-04-16 15:20:36 -0700681static int ipip_tunnel_change_mtu(struct net_device *dev, int new_mtu)
682{
683 if (new_mtu < 68 || new_mtu > 0xFFF8 - sizeof(struct iphdr))
684 return -EINVAL;
685 dev->mtu = new_mtu;
686 return 0;
687}
688
Stephen Hemminger23a12b12008-11-20 20:33:21 -0800689static const struct net_device_ops ipip_netdev_ops = {
690 .ndo_uninit = ipip_tunnel_uninit,
691 .ndo_start_xmit = ipip_tunnel_xmit,
692 .ndo_do_ioctl = ipip_tunnel_ioctl,
693 .ndo_change_mtu = ipip_tunnel_change_mtu,
694
695};
696
Linus Torvalds1da177e2005-04-16 15:20:36 -0700697static void ipip_tunnel_setup(struct net_device *dev)
698{
Stephen Hemminger23a12b12008-11-20 20:33:21 -0800699 dev->netdev_ops = &ipip_netdev_ops;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700700 dev->destructor = free_netdev;
701
702 dev->type = ARPHRD_TUNNEL;
703 dev->hard_header_len = LL_MAX_HEADER + sizeof(struct iphdr);
Kris Katterjohn46f25df2006-01-05 16:35:42 -0800704 dev->mtu = ETH_DATA_LEN - sizeof(struct iphdr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700705 dev->flags = IFF_NOARP;
706 dev->iflink = 0;
707 dev->addr_len = 4;
Pavel Emelyanov0a826402008-04-16 01:06:18 -0700708 dev->features |= NETIF_F_NETNS_LOCAL;
Eric Dumazet28e72212009-05-28 10:44:30 +0000709 dev->priv_flags &= ~IFF_XMIT_DST_RELEASE;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700710}
711
Stephen Hemminger23a12b12008-11-20 20:33:21 -0800712static void ipip_tunnel_init(struct net_device *dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700713{
Stephen Hemminger23a12b12008-11-20 20:33:21 -0800714 struct ip_tunnel *tunnel = netdev_priv(dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700715
716 tunnel->dev = dev;
717 strcpy(tunnel->parms.name, dev->name);
718
719 memcpy(dev->dev_addr, &tunnel->parms.iph.saddr, 4);
720 memcpy(dev->broadcast, &tunnel->parms.iph.daddr, 4);
721
Michal Schmidt55339952007-12-12 11:01:43 -0800722 ipip_tunnel_bind_dev(dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700723}
724
Stephen Hemminger23a12b12008-11-20 20:33:21 -0800725static void ipip_fb_tunnel_init(struct net_device *dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700726{
Patrick McHardy2941a482006-01-08 22:05:26 -0800727 struct ip_tunnel *tunnel = netdev_priv(dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700728 struct iphdr *iph = &tunnel->parms.iph;
Pavel Emelyanov44d3c292008-04-16 01:05:32 -0700729 struct ipip_net *ipn = net_generic(dev_net(dev), ipip_net_id);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700730
731 tunnel->dev = dev;
732 strcpy(tunnel->parms.name, dev->name);
733
734 iph->version = 4;
735 iph->protocol = IPPROTO_IPIP;
736 iph->ihl = 5;
737
738 dev_hold(dev);
Pavel Emelyanov44d3c292008-04-16 01:05:32 -0700739 ipn->tunnels_wc[0] = tunnel;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700740}
741
742static struct xfrm_tunnel ipip_handler = {
743 .handler = ipip_rcv,
744 .err_handler = ipip_err,
Herbert Xud2acc342006-03-28 01:12:13 -0800745 .priority = 1,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700746};
747
Stephen Hemminger5747a1a2009-02-22 00:02:08 -0800748static const char banner[] __initconst =
Linus Torvalds1da177e2005-04-16 15:20:36 -0700749 KERN_INFO "IPv4 over IPv4 tunneling driver\n";
750
Pavel Emelyanov44d3c292008-04-16 01:05:32 -0700751static void ipip_destroy_tunnels(struct ipip_net *ipn)
752{
753 int prio;
754
755 for (prio = 1; prio < 4; prio++) {
756 int h;
757 for (h = 0; h < HASH_SIZE; h++) {
758 struct ip_tunnel *t;
759 while ((t = ipn->tunnels[prio][h]) != NULL)
760 unregister_netdevice(t->dev);
761 }
762 }
763}
764
Pavel Emelyanov10dc4c72008-04-16 01:03:13 -0700765static int ipip_init_net(struct net *net)
766{
767 int err;
768 struct ipip_net *ipn;
769
770 err = -ENOMEM;
Pavel Emelyanov44d3c292008-04-16 01:05:32 -0700771 ipn = kzalloc(sizeof(struct ipip_net), GFP_KERNEL);
Pavel Emelyanov10dc4c72008-04-16 01:03:13 -0700772 if (ipn == NULL)
773 goto err_alloc;
774
775 err = net_assign_generic(net, ipip_net_id, ipn);
776 if (err < 0)
777 goto err_assign;
778
Pavel Emelyanov44d3c292008-04-16 01:05:32 -0700779 ipn->tunnels[0] = ipn->tunnels_wc;
780 ipn->tunnels[1] = ipn->tunnels_l;
781 ipn->tunnels[2] = ipn->tunnels_r;
782 ipn->tunnels[3] = ipn->tunnels_r_l;
783
Pavel Emelyanovb9855c52008-04-16 01:04:13 -0700784 ipn->fb_tunnel_dev = alloc_netdev(sizeof(struct ip_tunnel),
785 "tunl0",
786 ipip_tunnel_setup);
787 if (!ipn->fb_tunnel_dev) {
788 err = -ENOMEM;
789 goto err_alloc_dev;
790 }
Alexey Dobriyanbe77e592008-11-23 17:26:26 -0800791 dev_net_set(ipn->fb_tunnel_dev, net);
Pavel Emelyanovb9855c52008-04-16 01:04:13 -0700792
Stephen Hemminger23a12b12008-11-20 20:33:21 -0800793 ipip_fb_tunnel_init(ipn->fb_tunnel_dev);
Pavel Emelyanovb9855c52008-04-16 01:04:13 -0700794
795 if ((err = register_netdev(ipn->fb_tunnel_dev)))
796 goto err_reg_dev;
797
Pavel Emelyanov10dc4c72008-04-16 01:03:13 -0700798 return 0;
799
Pavel Emelyanovb9855c52008-04-16 01:04:13 -0700800err_reg_dev:
801 free_netdev(ipn->fb_tunnel_dev);
802err_alloc_dev:
803 /* nothing */
Pavel Emelyanov10dc4c72008-04-16 01:03:13 -0700804err_assign:
805 kfree(ipn);
806err_alloc:
807 return err;
808}
809
810static void ipip_exit_net(struct net *net)
811{
812 struct ipip_net *ipn;
813
814 ipn = net_generic(net, ipip_net_id);
Pavel Emelyanovb9855c52008-04-16 01:04:13 -0700815 rtnl_lock();
Pavel Emelyanov44d3c292008-04-16 01:05:32 -0700816 ipip_destroy_tunnels(ipn);
Pavel Emelyanovb9855c52008-04-16 01:04:13 -0700817 unregister_netdevice(ipn->fb_tunnel_dev);
818 rtnl_unlock();
Pavel Emelyanov10dc4c72008-04-16 01:03:13 -0700819 kfree(ipn);
820}
821
822static struct pernet_operations ipip_net_ops = {
823 .init = ipip_init_net,
824 .exit = ipip_exit_net,
825};
826
Linus Torvalds1da177e2005-04-16 15:20:36 -0700827static int __init ipip_init(void)
828{
829 int err;
830
831 printk(banner);
832
Kazunori MIYAZAWAc0d56402007-02-13 12:54:47 -0800833 if (xfrm4_tunnel_register(&ipip_handler, AF_INET)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700834 printk(KERN_INFO "ipip init: can't register tunnel\n");
835 return -EAGAIN;
836 }
837
Pavel Emelyanov10dc4c72008-04-16 01:03:13 -0700838 err = register_pernet_gen_device(&ipip_net_id, &ipip_net_ops);
839 if (err)
Pavel Emelyanovb9855c52008-04-16 01:04:13 -0700840 xfrm4_tunnel_deregister(&ipip_handler, AF_INET);
841
Linus Torvalds1da177e2005-04-16 15:20:36 -0700842 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700843}
844
845static void __exit ipip_fini(void)
846{
Kazunori MIYAZAWAc0d56402007-02-13 12:54:47 -0800847 if (xfrm4_tunnel_deregister(&ipip_handler, AF_INET))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700848 printk(KERN_INFO "ipip close: can't deregister tunnel\n");
849
Pavel Emelyanov10dc4c72008-04-16 01:03:13 -0700850 unregister_pernet_gen_device(ipip_net_id, &ipip_net_ops);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700851}
852
853module_init(ipip_init);
854module_exit(ipip_fini);
855MODULE_LICENSE("GPL");