blob: 29609d29df769350e9d1683209b372a422e9cd3d [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
Linus Torvalds1da177e2005-04-16 15:20:36 -0700133static int ipip_fb_tunnel_init(struct net_device *dev);
134static int ipip_tunnel_init(struct net_device *dev);
135static 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 dev->init = ipip_tunnel_init;
249 nt->parms = *parms;
250
Pavel Emelyanovb37d428b2008-02-26 23:51:04 -0800251 if (register_netdevice(dev) < 0)
252 goto failed_free;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700253
254 dev_hold(dev);
Pavel Emelyanovb9fae5c2008-04-16 01:04:35 -0700255 ipip_tunnel_link(ipn, nt);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700256 return nt;
257
Pavel Emelyanovb37d428b2008-02-26 23:51:04 -0800258failed_free:
259 free_netdev(dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700260 return NULL;
261}
262
263static void ipip_tunnel_uninit(struct net_device *dev)
264{
Pavel Emelyanovb9855c52008-04-16 01:04:13 -0700265 struct net *net = dev_net(dev);
266 struct ipip_net *ipn = net_generic(net, ipip_net_id);
267
268 if (dev == ipn->fb_tunnel_dev) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700269 write_lock_bh(&ipip_lock);
Pavel Emelyanov44d3c292008-04-16 01:05:32 -0700270 ipn->tunnels_wc[0] = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700271 write_unlock_bh(&ipip_lock);
272 } else
Pavel Emelyanovb9fae5c2008-04-16 01:04:35 -0700273 ipip_tunnel_unlink(ipn, netdev_priv(dev));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700274 dev_put(dev);
275}
276
Herbert Xud2acc342006-03-28 01:12:13 -0800277static int ipip_err(struct sk_buff *skb, u32 info)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700278{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700279
Rami Rosen071f92d2008-05-21 17:47:54 -0700280/* All the routers (except for Linux) return only
Linus Torvalds1da177e2005-04-16 15:20:36 -0700281 8 bytes of packet payload. It means, that precise relaying of
282 ICMP in the real Internet is absolutely infeasible.
283 */
284 struct iphdr *iph = (struct iphdr*)skb->data;
Arnaldo Carvalho de Melo88c76642007-03-13 14:43:18 -0300285 const int type = icmp_hdr(skb)->type;
286 const int code = icmp_hdr(skb)->code;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700287 struct ip_tunnel *t;
Herbert Xud2acc342006-03-28 01:12:13 -0800288 int err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700289
290 switch (type) {
291 default:
292 case ICMP_PARAMETERPROB:
Herbert Xud2acc342006-03-28 01:12:13 -0800293 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700294
295 case ICMP_DEST_UNREACH:
296 switch (code) {
297 case ICMP_SR_FAILED:
298 case ICMP_PORT_UNREACH:
299 /* Impossible event. */
Herbert Xud2acc342006-03-28 01:12:13 -0800300 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700301 case ICMP_FRAG_NEEDED:
302 /* Soft state for pmtu is maintained by IP core. */
Herbert Xud2acc342006-03-28 01:12:13 -0800303 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700304 default:
305 /* All others are translated to HOST_UNREACH.
306 rfc2003 contains "deep thoughts" about NET_UNREACH,
307 I believe they are just ether pollution. --ANK
308 */
309 break;
310 }
311 break;
312 case ICMP_TIME_EXCEEDED:
313 if (code != ICMP_EXC_TTL)
Herbert Xud2acc342006-03-28 01:12:13 -0800314 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700315 break;
316 }
317
Herbert Xud2acc342006-03-28 01:12:13 -0800318 err = -ENOENT;
319
Linus Torvalds1da177e2005-04-16 15:20:36 -0700320 read_lock(&ipip_lock);
Pavel Emelyanovcec3ffa2008-04-16 01:05:03 -0700321 t = ipip_tunnel_lookup(dev_net(skb->dev), iph->daddr, iph->saddr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700322 if (t == NULL || t->parms.iph.daddr == 0)
323 goto out;
Herbert Xud2acc342006-03-28 01:12:13 -0800324
325 err = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700326 if (t->parms.iph.ttl == 0 && type == ICMP_TIME_EXCEEDED)
327 goto out;
328
329 if (jiffies - t->err_time < IPTUNNEL_ERR_TIMEO)
330 t->err_count++;
331 else
332 t->err_count = 1;
333 t->err_time = jiffies;
334out:
335 read_unlock(&ipip_lock);
Herbert Xud2acc342006-03-28 01:12:13 -0800336 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700337}
338
Arnaldo Carvalho de Meloeddc9ec2007-04-20 22:47:35 -0700339static inline void ipip_ecn_decapsulate(const struct iphdr *outer_iph,
340 struct sk_buff *skb)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700341{
Arnaldo Carvalho de Meloeddc9ec2007-04-20 22:47:35 -0700342 struct iphdr *inner_iph = ip_hdr(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700343
344 if (INET_ECN_is_ce(outer_iph->tos))
345 IP_ECN_set_ce(inner_iph);
346}
347
348static int ipip_rcv(struct sk_buff *skb)
349{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700350 struct ip_tunnel *tunnel;
Arnaldo Carvalho de Meloeddc9ec2007-04-20 22:47:35 -0700351 const struct iphdr *iph = ip_hdr(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700352
353 read_lock(&ipip_lock);
Pavel Emelyanovcec3ffa2008-04-16 01:05:03 -0700354 if ((tunnel = ipip_tunnel_lookup(dev_net(skb->dev),
Pavel Emelyanovb9fae5c2008-04-16 01:04:35 -0700355 iph->saddr, iph->daddr)) != NULL) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700356 if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb)) {
357 read_unlock(&ipip_lock);
358 kfree_skb(skb);
359 return 0;
360 }
361
362 secpath_reset(skb);
363
Arnaldo Carvalho de Melob0e380b2007-04-10 21:21:55 -0700364 skb->mac_header = skb->network_header;
Arnaldo Carvalho de Meloc1d2bbe2007-04-10 20:45:18 -0700365 skb_reset_network_header(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700366 skb->protocol = htons(ETH_P_IP);
367 skb->pkt_type = PACKET_HOST;
368
Pavel Emelyanov50f59ce2008-05-21 14:15:16 -0700369 tunnel->dev->stats.rx_packets++;
370 tunnel->dev->stats.rx_bytes += skb->len;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700371 skb->dev = tunnel->dev;
372 dst_release(skb->dst);
373 skb->dst = NULL;
374 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
390static int ipip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev)
391{
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
405 if (tunnel->recursion++) {
Pavel Emelyanov50f59ce2008-05-21 14:15:16 -0700406 stats->collisions++;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700407 goto tx_error;
408 }
409
410 if (skb->protocol != htons(ETH_P_IP))
411 goto tx_error;
412
413 if (tos&1)
414 tos = old_iph->tos;
415
416 if (!dst) {
417 /* NBMA tunnel */
Eric Dumazetee6b9672008-03-05 18:30:47 -0800418 if ((rt = skb->rtable) == NULL) {
Pavel Emelyanov50f59ce2008-05-21 14:15:16 -0700419 stats->tx_fifo_errors++;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700420 goto tx_error;
421 }
422 if ((dst = rt->rt_gateway) == 0)
423 goto tx_error_icmp;
424 }
425
426 {
427 struct flowi fl = { .oif = tunnel->parms.link,
428 .nl_u = { .ip4_u =
429 { .daddr = dst,
430 .saddr = tiph->saddr,
431 .tos = RT_TOS(tos) } },
432 .proto = IPPROTO_IPIP };
Pavel Emelyanovb99f0152008-04-16 01:05:57 -0700433 if (ip_route_output_key(dev_net(dev), &rt, &fl)) {
Pavel Emelyanov50f59ce2008-05-21 14:15:16 -0700434 stats->tx_carrier_errors++;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700435 goto tx_error_icmp;
436 }
437 }
438 tdev = rt->u.dst.dev;
439
440 if (tdev == dev) {
441 ip_rt_put(rt);
Pavel Emelyanov50f59ce2008-05-21 14:15:16 -0700442 stats->collisions++;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700443 goto tx_error;
444 }
445
446 if (tiph->frag_off)
447 mtu = dst_mtu(&rt->u.dst) - sizeof(struct iphdr);
448 else
449 mtu = skb->dst ? dst_mtu(skb->dst) : dev->mtu;
450
451 if (mtu < 68) {
Pavel Emelyanov50f59ce2008-05-21 14:15:16 -0700452 stats->collisions++;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700453 ip_rt_put(rt);
454 goto tx_error;
455 }
456 if (skb->dst)
457 skb->dst->ops->update_pmtu(skb->dst, mtu);
458
459 df |= (old_iph->frag_off&htons(IP_DF));
460
461 if ((old_iph->frag_off&htons(IP_DF)) && mtu < ntohs(old_iph->tot_len)) {
462 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, htonl(mtu));
463 ip_rt_put(rt);
464 goto tx_error;
465 }
466
467 if (tunnel->err_count > 0) {
468 if (jiffies - tunnel->err_time < IPTUNNEL_ERR_TIMEO) {
469 tunnel->err_count--;
470 dst_link_failure(skb);
471 } else
472 tunnel->err_count = 0;
473 }
474
475 /*
476 * Okay, now see if we can stuff it in the buffer as-is.
477 */
478 max_headroom = (LL_RESERVED_SPACE(tdev)+sizeof(struct iphdr));
479
Patrick McHardycfbba492007-07-09 15:33:40 -0700480 if (skb_headroom(skb) < max_headroom || skb_shared(skb) ||
481 (skb_cloned(skb) && !skb_clone_writable(skb, 0))) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700482 struct sk_buff *new_skb = skb_realloc_headroom(skb, max_headroom);
483 if (!new_skb) {
484 ip_rt_put(rt);
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +0900485 stats->tx_dropped++;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700486 dev_kfree_skb(skb);
487 tunnel->recursion--;
488 return 0;
489 }
490 if (skb->sk)
491 skb_set_owner_w(new_skb, skb->sk);
492 dev_kfree_skb(skb);
493 skb = new_skb;
Arnaldo Carvalho de Meloeddc9ec2007-04-20 22:47:35 -0700494 old_iph = ip_hdr(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700495 }
496
Arnaldo Carvalho de Melob0e380b2007-04-10 21:21:55 -0700497 skb->transport_header = skb->network_header;
Arnaldo Carvalho de Meloe2d1bca2007-04-10 20:46:21 -0700498 skb_push(skb, sizeof(struct iphdr));
499 skb_reset_network_header(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700500 memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
Patrick McHardy48d5cad2006-02-15 15:10:22 -0800501 IPCB(skb)->flags &= ~(IPSKB_XFRM_TUNNEL_SIZE | IPSKB_XFRM_TRANSFORMED |
502 IPSKB_REROUTED);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700503 dst_release(skb->dst);
504 skb->dst = &rt->u.dst;
505
506 /*
507 * Push down and install the IPIP header.
508 */
509
Arnaldo Carvalho de Meloeddc9ec2007-04-20 22:47:35 -0700510 iph = ip_hdr(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700511 iph->version = 4;
512 iph->ihl = sizeof(struct iphdr)>>2;
513 iph->frag_off = df;
514 iph->protocol = IPPROTO_IPIP;
515 iph->tos = INET_ECN_encapsulate(tos, old_iph->tos);
516 iph->daddr = rt->rt_dst;
517 iph->saddr = rt->rt_src;
518
519 if ((iph->ttl = tiph->ttl) == 0)
520 iph->ttl = old_iph->ttl;
521
522 nf_reset(skb);
523
524 IPTUNNEL_XMIT();
525 tunnel->recursion--;
526 return 0;
527
528tx_error_icmp:
529 dst_link_failure(skb);
530tx_error:
531 stats->tx_errors++;
532 dev_kfree_skb(skb);
533 tunnel->recursion--;
534 return 0;
535}
536
Michal Schmidt55339952007-12-12 11:01:43 -0800537static void ipip_tunnel_bind_dev(struct net_device *dev)
538{
539 struct net_device *tdev = NULL;
540 struct ip_tunnel *tunnel;
541 struct iphdr *iph;
542
543 tunnel = netdev_priv(dev);
544 iph = &tunnel->parms.iph;
545
546 if (iph->daddr) {
547 struct flowi fl = { .oif = tunnel->parms.link,
548 .nl_u = { .ip4_u =
549 { .daddr = iph->daddr,
550 .saddr = iph->saddr,
551 .tos = RT_TOS(iph->tos) } },
552 .proto = IPPROTO_IPIP };
553 struct rtable *rt;
Pavel Emelyanovb99f0152008-04-16 01:05:57 -0700554 if (!ip_route_output_key(dev_net(dev), &rt, &fl)) {
Michal Schmidt55339952007-12-12 11:01:43 -0800555 tdev = rt->u.dst.dev;
556 ip_rt_put(rt);
557 }
558 dev->flags |= IFF_POINTOPOINT;
559 }
560
561 if (!tdev && tunnel->parms.link)
Pavel Emelyanovb99f0152008-04-16 01:05:57 -0700562 tdev = __dev_get_by_index(dev_net(dev), tunnel->parms.link);
Michal Schmidt55339952007-12-12 11:01:43 -0800563
564 if (tdev) {
565 dev->hard_header_len = tdev->hard_header_len + sizeof(struct iphdr);
566 dev->mtu = tdev->mtu - sizeof(struct iphdr);
567 }
568 dev->iflink = tunnel->parms.link;
569}
570
Linus Torvalds1da177e2005-04-16 15:20:36 -0700571static int
572ipip_tunnel_ioctl (struct net_device *dev, struct ifreq *ifr, int cmd)
573{
574 int err = 0;
575 struct ip_tunnel_parm p;
576 struct ip_tunnel *t;
Pavel Emelyanovb9855c52008-04-16 01:04:13 -0700577 struct net *net = dev_net(dev);
578 struct ipip_net *ipn = net_generic(net, ipip_net_id);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700579
580 switch (cmd) {
581 case SIOCGETTUNNEL:
582 t = NULL;
Pavel Emelyanovb9855c52008-04-16 01:04:13 -0700583 if (dev == ipn->fb_tunnel_dev) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700584 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) {
585 err = -EFAULT;
586 break;
587 }
Pavel Emelyanovb9fae5c2008-04-16 01:04:35 -0700588 t = ipip_tunnel_locate(net, &p, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700589 }
590 if (t == NULL)
Patrick McHardy2941a482006-01-08 22:05:26 -0800591 t = netdev_priv(dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700592 memcpy(&p, &t->parms, sizeof(p));
593 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
594 err = -EFAULT;
595 break;
596
597 case SIOCADDTUNNEL:
598 case SIOCCHGTUNNEL:
599 err = -EPERM;
600 if (!capable(CAP_NET_ADMIN))
601 goto done;
602
603 err = -EFAULT;
604 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
605 goto done;
606
607 err = -EINVAL;
608 if (p.iph.version != 4 || p.iph.protocol != IPPROTO_IPIP ||
609 p.iph.ihl != 5 || (p.iph.frag_off&htons(~IP_DF)))
610 goto done;
611 if (p.iph.ttl)
612 p.iph.frag_off |= htons(IP_DF);
613
Pavel Emelyanovb9fae5c2008-04-16 01:04:35 -0700614 t = ipip_tunnel_locate(net, &p, cmd == SIOCADDTUNNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700615
Pavel Emelyanovb9855c52008-04-16 01:04:13 -0700616 if (dev != ipn->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700617 if (t != NULL) {
618 if (t->dev != dev) {
619 err = -EEXIST;
620 break;
621 }
622 } else {
623 if (((dev->flags&IFF_POINTOPOINT) && !p.iph.daddr) ||
624 (!(dev->flags&IFF_POINTOPOINT) && p.iph.daddr)) {
625 err = -EINVAL;
626 break;
627 }
Patrick McHardy2941a482006-01-08 22:05:26 -0800628 t = netdev_priv(dev);
Pavel Emelyanovb9fae5c2008-04-16 01:04:35 -0700629 ipip_tunnel_unlink(ipn, t);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700630 t->parms.iph.saddr = p.iph.saddr;
631 t->parms.iph.daddr = p.iph.daddr;
632 memcpy(dev->dev_addr, &p.iph.saddr, 4);
633 memcpy(dev->broadcast, &p.iph.daddr, 4);
Pavel Emelyanovb9fae5c2008-04-16 01:04:35 -0700634 ipip_tunnel_link(ipn, t);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700635 netdev_state_change(dev);
636 }
637 }
638
639 if (t) {
640 err = 0;
641 if (cmd == SIOCCHGTUNNEL) {
642 t->parms.iph.ttl = p.iph.ttl;
643 t->parms.iph.tos = p.iph.tos;
644 t->parms.iph.frag_off = p.iph.frag_off;
Michal Schmidt55339952007-12-12 11:01:43 -0800645 if (t->parms.link != p.link) {
646 t->parms.link = p.link;
647 ipip_tunnel_bind_dev(dev);
648 netdev_state_change(dev);
649 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700650 }
651 if (copy_to_user(ifr->ifr_ifru.ifru_data, &t->parms, sizeof(p)))
652 err = -EFAULT;
653 } else
654 err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
655 break;
656
657 case SIOCDELTUNNEL:
658 err = -EPERM;
659 if (!capable(CAP_NET_ADMIN))
660 goto done;
661
Pavel Emelyanovb9855c52008-04-16 01:04:13 -0700662 if (dev == ipn->fb_tunnel_dev) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700663 err = -EFAULT;
664 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
665 goto done;
666 err = -ENOENT;
Pavel Emelyanovb9fae5c2008-04-16 01:04:35 -0700667 if ((t = ipip_tunnel_locate(net, &p, 0)) == NULL)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700668 goto done;
669 err = -EPERM;
Pavel Emelyanovb9855c52008-04-16 01:04:13 -0700670 if (t->dev == ipn->fb_tunnel_dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700671 goto done;
672 dev = t->dev;
673 }
Stephen Hemminger22f8cde2007-02-07 00:09:58 -0800674 unregister_netdevice(dev);
675 err = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700676 break;
677
678 default:
679 err = -EINVAL;
680 }
681
682done:
683 return err;
684}
685
Linus Torvalds1da177e2005-04-16 15:20:36 -0700686static int ipip_tunnel_change_mtu(struct net_device *dev, int new_mtu)
687{
688 if (new_mtu < 68 || new_mtu > 0xFFF8 - sizeof(struct iphdr))
689 return -EINVAL;
690 dev->mtu = new_mtu;
691 return 0;
692}
693
694static void ipip_tunnel_setup(struct net_device *dev)
695{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700696 dev->uninit = ipip_tunnel_uninit;
697 dev->hard_start_xmit = ipip_tunnel_xmit;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700698 dev->do_ioctl = ipip_tunnel_ioctl;
699 dev->change_mtu = ipip_tunnel_change_mtu;
700 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;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700709}
710
711static int ipip_tunnel_init(struct net_device *dev)
712{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700713 struct ip_tunnel *tunnel;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700714
Patrick McHardy2941a482006-01-08 22:05:26 -0800715 tunnel = netdev_priv(dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700716
717 tunnel->dev = dev;
718 strcpy(tunnel->parms.name, dev->name);
719
720 memcpy(dev->dev_addr, &tunnel->parms.iph.saddr, 4);
721 memcpy(dev->broadcast, &tunnel->parms.iph.daddr, 4);
722
Michal Schmidt55339952007-12-12 11:01:43 -0800723 ipip_tunnel_bind_dev(dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700724
725 return 0;
726}
727
Pavel Emelyanovb9855c52008-04-16 01:04:13 -0700728static int ipip_fb_tunnel_init(struct net_device *dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700729{
Patrick McHardy2941a482006-01-08 22:05:26 -0800730 struct ip_tunnel *tunnel = netdev_priv(dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700731 struct iphdr *iph = &tunnel->parms.iph;
Pavel Emelyanov44d3c292008-04-16 01:05:32 -0700732 struct ipip_net *ipn = net_generic(dev_net(dev), ipip_net_id);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700733
734 tunnel->dev = dev;
735 strcpy(tunnel->parms.name, dev->name);
736
737 iph->version = 4;
738 iph->protocol = IPPROTO_IPIP;
739 iph->ihl = 5;
740
741 dev_hold(dev);
Pavel Emelyanov44d3c292008-04-16 01:05:32 -0700742 ipn->tunnels_wc[0] = tunnel;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700743 return 0;
744}
745
746static struct xfrm_tunnel ipip_handler = {
747 .handler = ipip_rcv,
748 .err_handler = ipip_err,
Herbert Xud2acc342006-03-28 01:12:13 -0800749 .priority = 1,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700750};
751
752static char banner[] __initdata =
753 KERN_INFO "IPv4 over IPv4 tunneling driver\n";
754
Pavel Emelyanov44d3c292008-04-16 01:05:32 -0700755static void ipip_destroy_tunnels(struct ipip_net *ipn)
756{
757 int prio;
758
759 for (prio = 1; prio < 4; prio++) {
760 int h;
761 for (h = 0; h < HASH_SIZE; h++) {
762 struct ip_tunnel *t;
763 while ((t = ipn->tunnels[prio][h]) != NULL)
764 unregister_netdevice(t->dev);
765 }
766 }
767}
768
Pavel Emelyanov10dc4c72008-04-16 01:03:13 -0700769static int ipip_init_net(struct net *net)
770{
771 int err;
772 struct ipip_net *ipn;
773
774 err = -ENOMEM;
Pavel Emelyanov44d3c292008-04-16 01:05:32 -0700775 ipn = kzalloc(sizeof(struct ipip_net), GFP_KERNEL);
Pavel Emelyanov10dc4c72008-04-16 01:03:13 -0700776 if (ipn == NULL)
777 goto err_alloc;
778
779 err = net_assign_generic(net, ipip_net_id, ipn);
780 if (err < 0)
781 goto err_assign;
782
Pavel Emelyanov44d3c292008-04-16 01:05:32 -0700783 ipn->tunnels[0] = ipn->tunnels_wc;
784 ipn->tunnels[1] = ipn->tunnels_l;
785 ipn->tunnels[2] = ipn->tunnels_r;
786 ipn->tunnels[3] = ipn->tunnels_r_l;
787
Pavel Emelyanovb9855c52008-04-16 01:04:13 -0700788 ipn->fb_tunnel_dev = alloc_netdev(sizeof(struct ip_tunnel),
789 "tunl0",
790 ipip_tunnel_setup);
791 if (!ipn->fb_tunnel_dev) {
792 err = -ENOMEM;
793 goto err_alloc_dev;
794 }
795
796 ipn->fb_tunnel_dev->init = ipip_fb_tunnel_init;
797 dev_net_set(ipn->fb_tunnel_dev, net);
798
799 if ((err = register_netdev(ipn->fb_tunnel_dev)))
800 goto err_reg_dev;
801
Pavel Emelyanov10dc4c72008-04-16 01:03:13 -0700802 return 0;
803
Pavel Emelyanovb9855c52008-04-16 01:04:13 -0700804err_reg_dev:
805 free_netdev(ipn->fb_tunnel_dev);
806err_alloc_dev:
807 /* nothing */
Pavel Emelyanov10dc4c72008-04-16 01:03:13 -0700808err_assign:
809 kfree(ipn);
810err_alloc:
811 return err;
812}
813
814static void ipip_exit_net(struct net *net)
815{
816 struct ipip_net *ipn;
817
818 ipn = net_generic(net, ipip_net_id);
Pavel Emelyanovb9855c52008-04-16 01:04:13 -0700819 rtnl_lock();
Pavel Emelyanov44d3c292008-04-16 01:05:32 -0700820 ipip_destroy_tunnels(ipn);
Pavel Emelyanovb9855c52008-04-16 01:04:13 -0700821 unregister_netdevice(ipn->fb_tunnel_dev);
822 rtnl_unlock();
Pavel Emelyanov10dc4c72008-04-16 01:03:13 -0700823 kfree(ipn);
824}
825
826static struct pernet_operations ipip_net_ops = {
827 .init = ipip_init_net,
828 .exit = ipip_exit_net,
829};
830
Linus Torvalds1da177e2005-04-16 15:20:36 -0700831static int __init ipip_init(void)
832{
833 int err;
834
835 printk(banner);
836
Kazunori MIYAZAWAc0d56402007-02-13 12:54:47 -0800837 if (xfrm4_tunnel_register(&ipip_handler, AF_INET)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700838 printk(KERN_INFO "ipip init: can't register tunnel\n");
839 return -EAGAIN;
840 }
841
Pavel Emelyanov10dc4c72008-04-16 01:03:13 -0700842 err = register_pernet_gen_device(&ipip_net_id, &ipip_net_ops);
843 if (err)
Pavel Emelyanovb9855c52008-04-16 01:04:13 -0700844 xfrm4_tunnel_deregister(&ipip_handler, AF_INET);
845
Linus Torvalds1da177e2005-04-16 15:20:36 -0700846 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700847}
848
849static void __exit ipip_fini(void)
850{
Kazunori MIYAZAWAc0d56402007-02-13 12:54:47 -0800851 if (xfrm4_tunnel_deregister(&ipip_handler, AF_INET))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700852 printk(KERN_INFO "ipip close: can't deregister tunnel\n");
853
Pavel Emelyanov10dc4c72008-04-16 01:03:13 -0700854 unregister_pernet_gen_device(ipip_net_id, &ipip_net_ops);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700855}
856
857module_init(ipip_init);
858module_exit(ipip_fini);
859MODULE_LICENSE("GPL");