blob: 93e2b787da208aded55d00f2dab116ba629b8b22 [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 Emelyanovb37d4282008-02-26 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 Emelyanovb37d4282008-02-26 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 Emelyanovb37d4282008-02-26 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
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 Dumazet511c3f92009-06-02 05:14:27 +0000418 if ((rt = skb_rtable(skb)) == 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
Eric Dumazetadf30902009-06-02 05:19:30 +0000449 mtu = skb_dst(skb) ? dst_mtu(skb_dst(skb)) : dev->mtu;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700450
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 }
Eric Dumazetadf30902009-06-02 05:19:30 +0000456 if (skb_dst(skb))
457 skb_dst(skb)->ops->update_pmtu(skb_dst(skb), mtu);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700458
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) {
Wei Yongjun26d94b42009-02-24 23:36:47 -0800468 if (time_before(jiffies,
469 tunnel->err_time + IPTUNNEL_ERR_TIMEO)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700470 tunnel->err_count--;
471 dst_link_failure(skb);
472 } else
473 tunnel->err_count = 0;
474 }
475
476 /*
477 * Okay, now see if we can stuff it in the buffer as-is.
478 */
479 max_headroom = (LL_RESERVED_SPACE(tdev)+sizeof(struct iphdr));
480
Patrick McHardycfbba492007-07-09 15:33:40 -0700481 if (skb_headroom(skb) < max_headroom || skb_shared(skb) ||
482 (skb_cloned(skb) && !skb_clone_writable(skb, 0))) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700483 struct sk_buff *new_skb = skb_realloc_headroom(skb, max_headroom);
484 if (!new_skb) {
485 ip_rt_put(rt);
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +0900486 stats->tx_dropped++;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700487 dev_kfree_skb(skb);
488 tunnel->recursion--;
489 return 0;
490 }
491 if (skb->sk)
492 skb_set_owner_w(new_skb, skb->sk);
493 dev_kfree_skb(skb);
494 skb = new_skb;
Arnaldo Carvalho de Meloeddc9ec2007-04-20 22:47:35 -0700495 old_iph = ip_hdr(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700496 }
497
Arnaldo Carvalho de Melob0e380b2007-04-10 21:21:55 -0700498 skb->transport_header = skb->network_header;
Arnaldo Carvalho de Meloe2d1bca2007-04-10 20:46:21 -0700499 skb_push(skb, sizeof(struct iphdr));
500 skb_reset_network_header(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700501 memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
Patrick McHardy48d5cad2006-02-15 15:10:22 -0800502 IPCB(skb)->flags &= ~(IPSKB_XFRM_TUNNEL_SIZE | IPSKB_XFRM_TRANSFORMED |
503 IPSKB_REROUTED);
Eric Dumazetadf30902009-06-02 05:19:30 +0000504 skb_dst_drop(skb);
505 skb_dst_set(skb, &rt->u.dst);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700506
507 /*
508 * Push down and install the IPIP header.
509 */
510
Arnaldo Carvalho de Meloeddc9ec2007-04-20 22:47:35 -0700511 iph = ip_hdr(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700512 iph->version = 4;
513 iph->ihl = sizeof(struct iphdr)>>2;
514 iph->frag_off = df;
515 iph->protocol = IPPROTO_IPIP;
516 iph->tos = INET_ECN_encapsulate(tos, old_iph->tos);
517 iph->daddr = rt->rt_dst;
518 iph->saddr = rt->rt_src;
519
520 if ((iph->ttl = tiph->ttl) == 0)
521 iph->ttl = old_iph->ttl;
522
523 nf_reset(skb);
524
525 IPTUNNEL_XMIT();
526 tunnel->recursion--;
527 return 0;
528
529tx_error_icmp:
530 dst_link_failure(skb);
531tx_error:
532 stats->tx_errors++;
533 dev_kfree_skb(skb);
534 tunnel->recursion--;
535 return 0;
536}
537
Michal Schmidt55339952007-12-12 11:01:43 -0800538static void ipip_tunnel_bind_dev(struct net_device *dev)
539{
540 struct net_device *tdev = NULL;
541 struct ip_tunnel *tunnel;
542 struct iphdr *iph;
543
544 tunnel = netdev_priv(dev);
545 iph = &tunnel->parms.iph;
546
547 if (iph->daddr) {
548 struct flowi fl = { .oif = tunnel->parms.link,
549 .nl_u = { .ip4_u =
550 { .daddr = iph->daddr,
551 .saddr = iph->saddr,
552 .tos = RT_TOS(iph->tos) } },
553 .proto = IPPROTO_IPIP };
554 struct rtable *rt;
Pavel Emelyanovb99f0152008-04-16 01:05:57 -0700555 if (!ip_route_output_key(dev_net(dev), &rt, &fl)) {
Michal Schmidt55339952007-12-12 11:01:43 -0800556 tdev = rt->u.dst.dev;
557 ip_rt_put(rt);
558 }
559 dev->flags |= IFF_POINTOPOINT;
560 }
561
562 if (!tdev && tunnel->parms.link)
Pavel Emelyanovb99f0152008-04-16 01:05:57 -0700563 tdev = __dev_get_by_index(dev_net(dev), tunnel->parms.link);
Michal Schmidt55339952007-12-12 11:01:43 -0800564
565 if (tdev) {
566 dev->hard_header_len = tdev->hard_header_len + sizeof(struct iphdr);
567 dev->mtu = tdev->mtu - sizeof(struct iphdr);
568 }
569 dev->iflink = tunnel->parms.link;
570}
571
Linus Torvalds1da177e2005-04-16 15:20:36 -0700572static int
573ipip_tunnel_ioctl (struct net_device *dev, struct ifreq *ifr, int cmd)
574{
575 int err = 0;
576 struct ip_tunnel_parm p;
577 struct ip_tunnel *t;
Pavel Emelyanovb9855c52008-04-16 01:04:13 -0700578 struct net *net = dev_net(dev);
579 struct ipip_net *ipn = net_generic(net, ipip_net_id);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700580
581 switch (cmd) {
582 case SIOCGETTUNNEL:
583 t = NULL;
Pavel Emelyanovb9855c52008-04-16 01:04:13 -0700584 if (dev == ipn->fb_tunnel_dev) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700585 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) {
586 err = -EFAULT;
587 break;
588 }
Pavel Emelyanovb9fae5c2008-04-16 01:04:35 -0700589 t = ipip_tunnel_locate(net, &p, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700590 }
591 if (t == NULL)
Patrick McHardy2941a482006-01-08 22:05:26 -0800592 t = netdev_priv(dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700593 memcpy(&p, &t->parms, sizeof(p));
594 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
595 err = -EFAULT;
596 break;
597
598 case SIOCADDTUNNEL:
599 case SIOCCHGTUNNEL:
600 err = -EPERM;
601 if (!capable(CAP_NET_ADMIN))
602 goto done;
603
604 err = -EFAULT;
605 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
606 goto done;
607
608 err = -EINVAL;
609 if (p.iph.version != 4 || p.iph.protocol != IPPROTO_IPIP ||
610 p.iph.ihl != 5 || (p.iph.frag_off&htons(~IP_DF)))
611 goto done;
612 if (p.iph.ttl)
613 p.iph.frag_off |= htons(IP_DF);
614
Pavel Emelyanovb9fae5c2008-04-16 01:04:35 -0700615 t = ipip_tunnel_locate(net, &p, cmd == SIOCADDTUNNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700616
Pavel Emelyanovb9855c52008-04-16 01:04:13 -0700617 if (dev != ipn->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700618 if (t != NULL) {
619 if (t->dev != dev) {
620 err = -EEXIST;
621 break;
622 }
623 } else {
624 if (((dev->flags&IFF_POINTOPOINT) && !p.iph.daddr) ||
625 (!(dev->flags&IFF_POINTOPOINT) && p.iph.daddr)) {
626 err = -EINVAL;
627 break;
628 }
Patrick McHardy2941a482006-01-08 22:05:26 -0800629 t = netdev_priv(dev);
Pavel Emelyanovb9fae5c2008-04-16 01:04:35 -0700630 ipip_tunnel_unlink(ipn, t);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700631 t->parms.iph.saddr = p.iph.saddr;
632 t->parms.iph.daddr = p.iph.daddr;
633 memcpy(dev->dev_addr, &p.iph.saddr, 4);
634 memcpy(dev->broadcast, &p.iph.daddr, 4);
Pavel Emelyanovb9fae5c2008-04-16 01:04:35 -0700635 ipip_tunnel_link(ipn, t);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700636 netdev_state_change(dev);
637 }
638 }
639
640 if (t) {
641 err = 0;
642 if (cmd == SIOCCHGTUNNEL) {
643 t->parms.iph.ttl = p.iph.ttl;
644 t->parms.iph.tos = p.iph.tos;
645 t->parms.iph.frag_off = p.iph.frag_off;
Michal Schmidt55339952007-12-12 11:01:43 -0800646 if (t->parms.link != p.link) {
647 t->parms.link = p.link;
648 ipip_tunnel_bind_dev(dev);
649 netdev_state_change(dev);
650 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700651 }
652 if (copy_to_user(ifr->ifr_ifru.ifru_data, &t->parms, sizeof(p)))
653 err = -EFAULT;
654 } else
655 err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
656 break;
657
658 case SIOCDELTUNNEL:
659 err = -EPERM;
660 if (!capable(CAP_NET_ADMIN))
661 goto done;
662
Pavel Emelyanovb9855c52008-04-16 01:04:13 -0700663 if (dev == ipn->fb_tunnel_dev) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700664 err = -EFAULT;
665 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
666 goto done;
667 err = -ENOENT;
Pavel Emelyanovb9fae5c2008-04-16 01:04:35 -0700668 if ((t = ipip_tunnel_locate(net, &p, 0)) == NULL)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700669 goto done;
670 err = -EPERM;
Pavel Emelyanovb9855c52008-04-16 01:04:13 -0700671 if (t->dev == ipn->fb_tunnel_dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700672 goto done;
673 dev = t->dev;
674 }
Stephen Hemminger22f8cde2007-02-07 00:09:58 -0800675 unregister_netdevice(dev);
676 err = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700677 break;
678
679 default:
680 err = -EINVAL;
681 }
682
683done:
684 return err;
685}
686
Linus Torvalds1da177e2005-04-16 15:20:36 -0700687static int ipip_tunnel_change_mtu(struct net_device *dev, int new_mtu)
688{
689 if (new_mtu < 68 || new_mtu > 0xFFF8 - sizeof(struct iphdr))
690 return -EINVAL;
691 dev->mtu = new_mtu;
692 return 0;
693}
694
Stephen Hemminger23a12b12008-11-20 20:33:21 -0800695static const struct net_device_ops ipip_netdev_ops = {
696 .ndo_uninit = ipip_tunnel_uninit,
697 .ndo_start_xmit = ipip_tunnel_xmit,
698 .ndo_do_ioctl = ipip_tunnel_ioctl,
699 .ndo_change_mtu = ipip_tunnel_change_mtu,
700
701};
702
Linus Torvalds1da177e2005-04-16 15:20:36 -0700703static void ipip_tunnel_setup(struct net_device *dev)
704{
Stephen Hemminger23a12b12008-11-20 20:33:21 -0800705 dev->netdev_ops = &ipip_netdev_ops;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700706 dev->destructor = free_netdev;
707
708 dev->type = ARPHRD_TUNNEL;
709 dev->hard_header_len = LL_MAX_HEADER + sizeof(struct iphdr);
Kris Katterjohn46f25df2006-01-05 16:35:42 -0800710 dev->mtu = ETH_DATA_LEN - sizeof(struct iphdr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700711 dev->flags = IFF_NOARP;
712 dev->iflink = 0;
713 dev->addr_len = 4;
Pavel Emelyanov0a826402008-04-16 01:06:18 -0700714 dev->features |= NETIF_F_NETNS_LOCAL;
Eric Dumazet28e72212009-05-28 10:44:30 +0000715 dev->priv_flags &= ~IFF_XMIT_DST_RELEASE;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700716}
717
Stephen Hemminger23a12b12008-11-20 20:33:21 -0800718static void ipip_tunnel_init(struct net_device *dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700719{
Stephen Hemminger23a12b12008-11-20 20:33:21 -0800720 struct ip_tunnel *tunnel = netdev_priv(dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700721
722 tunnel->dev = dev;
723 strcpy(tunnel->parms.name, dev->name);
724
725 memcpy(dev->dev_addr, &tunnel->parms.iph.saddr, 4);
726 memcpy(dev->broadcast, &tunnel->parms.iph.daddr, 4);
727
Michal Schmidt55339952007-12-12 11:01:43 -0800728 ipip_tunnel_bind_dev(dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700729}
730
Stephen Hemminger23a12b12008-11-20 20:33:21 -0800731static void ipip_fb_tunnel_init(struct net_device *dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700732{
Patrick McHardy2941a482006-01-08 22:05:26 -0800733 struct ip_tunnel *tunnel = netdev_priv(dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700734 struct iphdr *iph = &tunnel->parms.iph;
Pavel Emelyanov44d3c292008-04-16 01:05:32 -0700735 struct ipip_net *ipn = net_generic(dev_net(dev), ipip_net_id);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700736
737 tunnel->dev = dev;
738 strcpy(tunnel->parms.name, dev->name);
739
740 iph->version = 4;
741 iph->protocol = IPPROTO_IPIP;
742 iph->ihl = 5;
743
744 dev_hold(dev);
Pavel Emelyanov44d3c292008-04-16 01:05:32 -0700745 ipn->tunnels_wc[0] = tunnel;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700746}
747
748static struct xfrm_tunnel ipip_handler = {
749 .handler = ipip_rcv,
750 .err_handler = ipip_err,
Herbert Xud2acc342006-03-28 01:12:13 -0800751 .priority = 1,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700752};
753
Stephen Hemminger5747a1a2009-02-22 00:02:08 -0800754static const char banner[] __initconst =
Linus Torvalds1da177e2005-04-16 15:20:36 -0700755 KERN_INFO "IPv4 over IPv4 tunneling driver\n";
756
Pavel Emelyanov44d3c292008-04-16 01:05:32 -0700757static void ipip_destroy_tunnels(struct ipip_net *ipn)
758{
759 int prio;
760
761 for (prio = 1; prio < 4; prio++) {
762 int h;
763 for (h = 0; h < HASH_SIZE; h++) {
764 struct ip_tunnel *t;
765 while ((t = ipn->tunnels[prio][h]) != NULL)
766 unregister_netdevice(t->dev);
767 }
768 }
769}
770
Pavel Emelyanov10dc4c72008-04-16 01:03:13 -0700771static int ipip_init_net(struct net *net)
772{
773 int err;
774 struct ipip_net *ipn;
775
776 err = -ENOMEM;
Pavel Emelyanov44d3c292008-04-16 01:05:32 -0700777 ipn = kzalloc(sizeof(struct ipip_net), GFP_KERNEL);
Pavel Emelyanov10dc4c72008-04-16 01:03:13 -0700778 if (ipn == NULL)
779 goto err_alloc;
780
781 err = net_assign_generic(net, ipip_net_id, ipn);
782 if (err < 0)
783 goto err_assign;
784
Pavel Emelyanov44d3c292008-04-16 01:05:32 -0700785 ipn->tunnels[0] = ipn->tunnels_wc;
786 ipn->tunnels[1] = ipn->tunnels_l;
787 ipn->tunnels[2] = ipn->tunnels_r;
788 ipn->tunnels[3] = ipn->tunnels_r_l;
789
Pavel Emelyanovb9855c52008-04-16 01:04:13 -0700790 ipn->fb_tunnel_dev = alloc_netdev(sizeof(struct ip_tunnel),
791 "tunl0",
792 ipip_tunnel_setup);
793 if (!ipn->fb_tunnel_dev) {
794 err = -ENOMEM;
795 goto err_alloc_dev;
796 }
Alexey Dobriyanbe77e592008-11-23 17:26:26 -0800797 dev_net_set(ipn->fb_tunnel_dev, net);
Pavel Emelyanovb9855c52008-04-16 01:04:13 -0700798
Stephen Hemminger23a12b12008-11-20 20:33:21 -0800799 ipip_fb_tunnel_init(ipn->fb_tunnel_dev);
Pavel Emelyanovb9855c52008-04-16 01:04:13 -0700800
801 if ((err = register_netdev(ipn->fb_tunnel_dev)))
802 goto err_reg_dev;
803
Pavel Emelyanov10dc4c72008-04-16 01:03:13 -0700804 return 0;
805
Pavel Emelyanovb9855c52008-04-16 01:04:13 -0700806err_reg_dev:
807 free_netdev(ipn->fb_tunnel_dev);
808err_alloc_dev:
809 /* nothing */
Pavel Emelyanov10dc4c72008-04-16 01:03:13 -0700810err_assign:
811 kfree(ipn);
812err_alloc:
813 return err;
814}
815
816static void ipip_exit_net(struct net *net)
817{
818 struct ipip_net *ipn;
819
820 ipn = net_generic(net, ipip_net_id);
Pavel Emelyanovb9855c52008-04-16 01:04:13 -0700821 rtnl_lock();
Pavel Emelyanov44d3c292008-04-16 01:05:32 -0700822 ipip_destroy_tunnels(ipn);
Pavel Emelyanovb9855c52008-04-16 01:04:13 -0700823 unregister_netdevice(ipn->fb_tunnel_dev);
824 rtnl_unlock();
Pavel Emelyanov10dc4c72008-04-16 01:03:13 -0700825 kfree(ipn);
826}
827
828static struct pernet_operations ipip_net_ops = {
829 .init = ipip_init_net,
830 .exit = ipip_exit_net,
831};
832
Linus Torvalds1da177e2005-04-16 15:20:36 -0700833static int __init ipip_init(void)
834{
835 int err;
836
837 printk(banner);
838
Kazunori MIYAZAWAc0d56402007-02-13 12:54:47 -0800839 if (xfrm4_tunnel_register(&ipip_handler, AF_INET)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700840 printk(KERN_INFO "ipip init: can't register tunnel\n");
841 return -EAGAIN;
842 }
843
Pavel Emelyanov10dc4c72008-04-16 01:03:13 -0700844 err = register_pernet_gen_device(&ipip_net_id, &ipip_net_ops);
845 if (err)
Pavel Emelyanovb9855c52008-04-16 01:04:13 -0700846 xfrm4_tunnel_deregister(&ipip_handler, AF_INET);
847
Linus Torvalds1da177e2005-04-16 15:20:36 -0700848 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700849}
850
851static void __exit ipip_fini(void)
852{
Kazunori MIYAZAWAc0d56402007-02-13 12:54:47 -0800853 if (xfrm4_tunnel_deregister(&ipip_handler, AF_INET))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700854 printk(KERN_INFO "ipip close: can't deregister tunnel\n");
855
Pavel Emelyanov10dc4c72008-04-16 01:03:13 -0700856 unregister_pernet_gen_device(ipip_net_id, &ipip_net_ops);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700857}
858
859module_init(ipip_init);
860module_exit(ipip_fini);
861MODULE_LICENSE("GPL");