diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
---|---|---|
committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /net/ipv4/ipip.c |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'net/ipv4/ipip.c')
-rw-r--r-- | net/ipv4/ipip.c | 905 |
1 files changed, 905 insertions, 0 deletions
diff --git a/net/ipv4/ipip.c b/net/ipv4/ipip.c new file mode 100644 index 000000000000..68a78731f722 --- /dev/null +++ b/net/ipv4/ipip.c | |||
@@ -0,0 +1,905 @@ | |||
1 | /* | ||
2 | * Linux NET3: IP/IP protocol decoder. | ||
3 | * | ||
4 | * Version: $Id: ipip.c,v 1.50 2001/10/02 02:22:36 davem Exp $ | ||
5 | * | ||
6 | * Authors: | ||
7 | * Sam Lantinga (slouken@cs.ucdavis.edu) 02/01/95 | ||
8 | * | ||
9 | * Fixes: | ||
10 | * Alan Cox : Merged and made usable non modular (its so tiny its silly as | ||
11 | * a module taking up 2 pages). | ||
12 | * Alan Cox : Fixed bug with 1.3.18 and IPIP not working (now needs to set skb->h.iph) | ||
13 | * to keep ip_forward happy. | ||
14 | * Alan Cox : More fixes for 1.3.21, and firewall fix. Maybe this will work soon 8). | ||
15 | * Kai Schulte : Fixed #defines for IP_FIREWALL->FIREWALL | ||
16 | * David Woodhouse : Perform some basic ICMP handling. | ||
17 | * IPIP Routing without decapsulation. | ||
18 | * Carlos Picoto : GRE over IP support | ||
19 | * Alexey Kuznetsov: Reworked. Really, now it is truncated version of ipv4/ip_gre.c. | ||
20 | * I do not want to merge them together. | ||
21 | * | ||
22 | * This program is free software; you can redistribute it and/or | ||
23 | * modify it under the terms of the GNU General Public License | ||
24 | * as published by the Free Software Foundation; either version | ||
25 | * 2 of the License, or (at your option) any later version. | ||
26 | * | ||
27 | */ | ||
28 | |||
29 | /* tunnel.c: an IP tunnel driver | ||
30 | |||
31 | The purpose of this driver is to provide an IP tunnel through | ||
32 | which you can tunnel network traffic transparently across subnets. | ||
33 | |||
34 | This was written by looking at Nick Holloway's dummy driver | ||
35 | Thanks for the great code! | ||
36 | |||
37 | -Sam Lantinga (slouken@cs.ucdavis.edu) 02/01/95 | ||
38 | |||
39 | Minor tweaks: | ||
40 | Cleaned up the code a little and added some pre-1.3.0 tweaks. | ||
41 | dev->hard_header/hard_header_len changed to use no headers. | ||
42 | Comments/bracketing tweaked. | ||
43 | Made the tunnels use dev->name not tunnel: when error reporting. | ||
44 | Added tx_dropped stat | ||
45 | |||
46 | -Alan Cox (Alan.Cox@linux.org) 21 March 95 | ||
47 | |||
48 | Reworked: | ||
49 | Changed to tunnel to destination gateway in addition to the | ||
50 | tunnel's pointopoint address | ||
51 | Almost completely rewritten | ||
52 | Note: There is currently no firewall or ICMP handling done. | ||
53 | |||
54 | -Sam Lantinga (slouken@cs.ucdavis.edu) 02/13/96 | ||
55 | |||
56 | */ | ||
57 | |||
58 | /* Things I wish I had known when writing the tunnel driver: | ||
59 | |||
60 | When the tunnel_xmit() function is called, the skb contains the | ||
61 | packet to be sent (plus a great deal of extra info), and dev | ||
62 | contains the tunnel device that _we_ are. | ||
63 | |||
64 | When we are passed a packet, we are expected to fill in the | ||
65 | source address with our source IP address. | ||
66 | |||
67 | What is the proper way to allocate, copy and free a buffer? | ||
68 | After you allocate it, it is a "0 length" chunk of memory | ||
69 | starting at zero. If you want to add headers to the buffer | ||
70 | later, you'll have to call "skb_reserve(skb, amount)" with | ||
71 | the amount of memory you want reserved. Then, you call | ||
72 | "skb_put(skb, amount)" with the amount of space you want in | ||
73 | the buffer. skb_put() returns a pointer to the top (#0) of | ||
74 | that buffer. skb->len is set to the amount of space you have | ||
75 | "allocated" with skb_put(). You can then write up to skb->len | ||
76 | bytes to that buffer. If you need more, you can call skb_put() | ||
77 | again with the additional amount of space you need. You can | ||
78 | find out how much more space you can allocate by calling | ||
79 | "skb_tailroom(skb)". | ||
80 | Now, to add header space, call "skb_push(skb, header_len)". | ||
81 | This creates space at the beginning of the buffer and returns | ||
82 | a pointer to this new space. If later you need to strip a | ||
83 | header from a buffer, call "skb_pull(skb, header_len)". | ||
84 | skb_headroom() will return how much space is left at the top | ||
85 | of the buffer (before the main data). Remember, this headroom | ||
86 | space must be reserved before the skb_put() function is called. | ||
87 | */ | ||
88 | |||
89 | /* | ||
90 | This version of net/ipv4/ipip.c is cloned of net/ipv4/ip_gre.c | ||
91 | |||
92 | For comments look at net/ipv4/ip_gre.c --ANK | ||
93 | */ | ||
94 | |||
95 | |||
96 | #include <linux/config.h> | ||
97 | #include <linux/module.h> | ||
98 | #include <linux/types.h> | ||
99 | #include <linux/sched.h> | ||
100 | #include <linux/kernel.h> | ||
101 | #include <asm/uaccess.h> | ||
102 | #include <linux/skbuff.h> | ||
103 | #include <linux/netdevice.h> | ||
104 | #include <linux/in.h> | ||
105 | #include <linux/tcp.h> | ||
106 | #include <linux/udp.h> | ||
107 | #include <linux/if_arp.h> | ||
108 | #include <linux/mroute.h> | ||
109 | #include <linux/init.h> | ||
110 | #include <linux/netfilter_ipv4.h> | ||
111 | |||
112 | #include <net/sock.h> | ||
113 | #include <net/ip.h> | ||
114 | #include <net/icmp.h> | ||
115 | #include <net/protocol.h> | ||
116 | #include <net/ipip.h> | ||
117 | #include <net/inet_ecn.h> | ||
118 | #include <net/xfrm.h> | ||
119 | |||
120 | #define HASH_SIZE 16 | ||
121 | #define HASH(addr) ((addr^(addr>>4))&0xF) | ||
122 | |||
123 | static int ipip_fb_tunnel_init(struct net_device *dev); | ||
124 | static int ipip_tunnel_init(struct net_device *dev); | ||
125 | static void ipip_tunnel_setup(struct net_device *dev); | ||
126 | |||
127 | static struct net_device *ipip_fb_tunnel_dev; | ||
128 | |||
129 | static struct ip_tunnel *tunnels_r_l[HASH_SIZE]; | ||
130 | static struct ip_tunnel *tunnels_r[HASH_SIZE]; | ||
131 | static struct ip_tunnel *tunnels_l[HASH_SIZE]; | ||
132 | static struct ip_tunnel *tunnels_wc[1]; | ||
133 | static struct ip_tunnel **tunnels[4] = { tunnels_wc, tunnels_l, tunnels_r, tunnels_r_l }; | ||
134 | |||
135 | static DEFINE_RWLOCK(ipip_lock); | ||
136 | |||
137 | static struct ip_tunnel * ipip_tunnel_lookup(u32 remote, u32 local) | ||
138 | { | ||
139 | unsigned h0 = HASH(remote); | ||
140 | unsigned h1 = HASH(local); | ||
141 | struct ip_tunnel *t; | ||
142 | |||
143 | for (t = tunnels_r_l[h0^h1]; t; t = t->next) { | ||
144 | if (local == t->parms.iph.saddr && | ||
145 | remote == t->parms.iph.daddr && (t->dev->flags&IFF_UP)) | ||
146 | return t; | ||
147 | } | ||
148 | for (t = tunnels_r[h0]; t; t = t->next) { | ||
149 | if (remote == t->parms.iph.daddr && (t->dev->flags&IFF_UP)) | ||
150 | return t; | ||
151 | } | ||
152 | for (t = tunnels_l[h1]; t; t = t->next) { | ||
153 | if (local == t->parms.iph.saddr && (t->dev->flags&IFF_UP)) | ||
154 | return t; | ||
155 | } | ||
156 | if ((t = tunnels_wc[0]) != NULL && (t->dev->flags&IFF_UP)) | ||
157 | return t; | ||
158 | return NULL; | ||
159 | } | ||
160 | |||
161 | static struct ip_tunnel **ipip_bucket(struct ip_tunnel *t) | ||
162 | { | ||
163 | u32 remote = t->parms.iph.daddr; | ||
164 | u32 local = t->parms.iph.saddr; | ||
165 | unsigned h = 0; | ||
166 | int prio = 0; | ||
167 | |||
168 | if (remote) { | ||
169 | prio |= 2; | ||
170 | h ^= HASH(remote); | ||
171 | } | ||
172 | if (local) { | ||
173 | prio |= 1; | ||
174 | h ^= HASH(local); | ||
175 | } | ||
176 | return &tunnels[prio][h]; | ||
177 | } | ||
178 | |||
179 | |||
180 | static void ipip_tunnel_unlink(struct ip_tunnel *t) | ||
181 | { | ||
182 | struct ip_tunnel **tp; | ||
183 | |||
184 | for (tp = ipip_bucket(t); *tp; tp = &(*tp)->next) { | ||
185 | if (t == *tp) { | ||
186 | write_lock_bh(&ipip_lock); | ||
187 | *tp = t->next; | ||
188 | write_unlock_bh(&ipip_lock); | ||
189 | break; | ||
190 | } | ||
191 | } | ||
192 | } | ||
193 | |||
194 | static void ipip_tunnel_link(struct ip_tunnel *t) | ||
195 | { | ||
196 | struct ip_tunnel **tp = ipip_bucket(t); | ||
197 | |||
198 | t->next = *tp; | ||
199 | write_lock_bh(&ipip_lock); | ||
200 | *tp = t; | ||
201 | write_unlock_bh(&ipip_lock); | ||
202 | } | ||
203 | |||
204 | static struct ip_tunnel * ipip_tunnel_locate(struct ip_tunnel_parm *parms, int create) | ||
205 | { | ||
206 | u32 remote = parms->iph.daddr; | ||
207 | u32 local = parms->iph.saddr; | ||
208 | struct ip_tunnel *t, **tp, *nt; | ||
209 | struct net_device *dev; | ||
210 | unsigned h = 0; | ||
211 | int prio = 0; | ||
212 | char name[IFNAMSIZ]; | ||
213 | |||
214 | if (remote) { | ||
215 | prio |= 2; | ||
216 | h ^= HASH(remote); | ||
217 | } | ||
218 | if (local) { | ||
219 | prio |= 1; | ||
220 | h ^= HASH(local); | ||
221 | } | ||
222 | for (tp = &tunnels[prio][h]; (t = *tp) != NULL; tp = &t->next) { | ||
223 | if (local == t->parms.iph.saddr && remote == t->parms.iph.daddr) | ||
224 | return t; | ||
225 | } | ||
226 | if (!create) | ||
227 | return NULL; | ||
228 | |||
229 | if (parms->name[0]) | ||
230 | strlcpy(name, parms->name, IFNAMSIZ); | ||
231 | else { | ||
232 | int i; | ||
233 | for (i=1; i<100; i++) { | ||
234 | sprintf(name, "tunl%d", i); | ||
235 | if (__dev_get_by_name(name) == NULL) | ||
236 | break; | ||
237 | } | ||
238 | if (i==100) | ||
239 | goto failed; | ||
240 | } | ||
241 | |||
242 | dev = alloc_netdev(sizeof(*t), name, ipip_tunnel_setup); | ||
243 | if (dev == NULL) | ||
244 | return NULL; | ||
245 | |||
246 | nt = dev->priv; | ||
247 | SET_MODULE_OWNER(dev); | ||
248 | dev->init = ipip_tunnel_init; | ||
249 | nt->parms = *parms; | ||
250 | |||
251 | if (register_netdevice(dev) < 0) { | ||
252 | free_netdev(dev); | ||
253 | goto failed; | ||
254 | } | ||
255 | |||
256 | dev_hold(dev); | ||
257 | ipip_tunnel_link(nt); | ||
258 | /* Do not decrement MOD_USE_COUNT here. */ | ||
259 | return nt; | ||
260 | |||
261 | failed: | ||
262 | return NULL; | ||
263 | } | ||
264 | |||
265 | static void ipip_tunnel_uninit(struct net_device *dev) | ||
266 | { | ||
267 | if (dev == ipip_fb_tunnel_dev) { | ||
268 | write_lock_bh(&ipip_lock); | ||
269 | tunnels_wc[0] = NULL; | ||
270 | write_unlock_bh(&ipip_lock); | ||
271 | } else | ||
272 | ipip_tunnel_unlink((struct ip_tunnel*)dev->priv); | ||
273 | dev_put(dev); | ||
274 | } | ||
275 | |||
276 | static void ipip_err(struct sk_buff *skb, void *__unused) | ||
277 | { | ||
278 | #ifndef I_WISH_WORLD_WERE_PERFECT | ||
279 | |||
280 | /* It is not :-( All the routers (except for Linux) return only | ||
281 | 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; | ||
285 | int type = skb->h.icmph->type; | ||
286 | int code = skb->h.icmph->code; | ||
287 | struct ip_tunnel *t; | ||
288 | |||
289 | switch (type) { | ||
290 | default: | ||
291 | case ICMP_PARAMETERPROB: | ||
292 | return; | ||
293 | |||
294 | case ICMP_DEST_UNREACH: | ||
295 | switch (code) { | ||
296 | case ICMP_SR_FAILED: | ||
297 | case ICMP_PORT_UNREACH: | ||
298 | /* Impossible event. */ | ||
299 | return; | ||
300 | case ICMP_FRAG_NEEDED: | ||
301 | /* Soft state for pmtu is maintained by IP core. */ | ||
302 | return; | ||
303 | default: | ||
304 | /* All others are translated to HOST_UNREACH. | ||
305 | rfc2003 contains "deep thoughts" about NET_UNREACH, | ||
306 | I believe they are just ether pollution. --ANK | ||
307 | */ | ||
308 | break; | ||
309 | } | ||
310 | break; | ||
311 | case ICMP_TIME_EXCEEDED: | ||
312 | if (code != ICMP_EXC_TTL) | ||
313 | return; | ||
314 | break; | ||
315 | } | ||
316 | |||
317 | read_lock(&ipip_lock); | ||
318 | t = ipip_tunnel_lookup(iph->daddr, iph->saddr); | ||
319 | if (t == NULL || t->parms.iph.daddr == 0) | ||
320 | goto out; | ||
321 | if (t->parms.iph.ttl == 0 && type == ICMP_TIME_EXCEEDED) | ||
322 | goto out; | ||
323 | |||
324 | if (jiffies - t->err_time < IPTUNNEL_ERR_TIMEO) | ||
325 | t->err_count++; | ||
326 | else | ||
327 | t->err_count = 1; | ||
328 | t->err_time = jiffies; | ||
329 | out: | ||
330 | read_unlock(&ipip_lock); | ||
331 | return; | ||
332 | #else | ||
333 | struct iphdr *iph = (struct iphdr*)dp; | ||
334 | int hlen = iph->ihl<<2; | ||
335 | struct iphdr *eiph; | ||
336 | int type = skb->h.icmph->type; | ||
337 | int code = skb->h.icmph->code; | ||
338 | int rel_type = 0; | ||
339 | int rel_code = 0; | ||
340 | int rel_info = 0; | ||
341 | struct sk_buff *skb2; | ||
342 | struct flowi fl; | ||
343 | struct rtable *rt; | ||
344 | |||
345 | if (len < hlen + sizeof(struct iphdr)) | ||
346 | return; | ||
347 | eiph = (struct iphdr*)(dp + hlen); | ||
348 | |||
349 | switch (type) { | ||
350 | default: | ||
351 | return; | ||
352 | case ICMP_PARAMETERPROB: | ||
353 | if (skb->h.icmph->un.gateway < hlen) | ||
354 | return; | ||
355 | |||
356 | /* So... This guy found something strange INSIDE encapsulated | ||
357 | packet. Well, he is fool, but what can we do ? | ||
358 | */ | ||
359 | rel_type = ICMP_PARAMETERPROB; | ||
360 | rel_info = skb->h.icmph->un.gateway - hlen; | ||
361 | break; | ||
362 | |||
363 | case ICMP_DEST_UNREACH: | ||
364 | switch (code) { | ||
365 | case ICMP_SR_FAILED: | ||
366 | case ICMP_PORT_UNREACH: | ||
367 | /* Impossible event. */ | ||
368 | return; | ||
369 | case ICMP_FRAG_NEEDED: | ||
370 | /* And it is the only really necessary thing :-) */ | ||
371 | rel_info = ntohs(skb->h.icmph->un.frag.mtu); | ||
372 | if (rel_info < hlen+68) | ||
373 | return; | ||
374 | rel_info -= hlen; | ||
375 | /* BSD 4.2 MORE DOES NOT EXIST IN NATURE. */ | ||
376 | if (rel_info > ntohs(eiph->tot_len)) | ||
377 | return; | ||
378 | break; | ||
379 | default: | ||
380 | /* All others are translated to HOST_UNREACH. | ||
381 | rfc2003 contains "deep thoughts" about NET_UNREACH, | ||
382 | I believe, it is just ether pollution. --ANK | ||
383 | */ | ||
384 | rel_type = ICMP_DEST_UNREACH; | ||
385 | rel_code = ICMP_HOST_UNREACH; | ||
386 | break; | ||
387 | } | ||
388 | break; | ||
389 | case ICMP_TIME_EXCEEDED: | ||
390 | if (code != ICMP_EXC_TTL) | ||
391 | return; | ||
392 | break; | ||
393 | } | ||
394 | |||
395 | /* Prepare fake skb to feed it to icmp_send */ | ||
396 | skb2 = skb_clone(skb, GFP_ATOMIC); | ||
397 | if (skb2 == NULL) | ||
398 | return; | ||
399 | dst_release(skb2->dst); | ||
400 | skb2->dst = NULL; | ||
401 | skb_pull(skb2, skb->data - (u8*)eiph); | ||
402 | skb2->nh.raw = skb2->data; | ||
403 | |||
404 | /* Try to guess incoming interface */ | ||
405 | memset(&fl, 0, sizeof(fl)); | ||
406 | fl.fl4_daddr = eiph->saddr; | ||
407 | fl.fl4_tos = RT_TOS(eiph->tos); | ||
408 | fl.proto = IPPROTO_IPIP; | ||
409 | if (ip_route_output_key(&rt, &key)) { | ||
410 | kfree_skb(skb2); | ||
411 | return; | ||
412 | } | ||
413 | skb2->dev = rt->u.dst.dev; | ||
414 | |||
415 | /* route "incoming" packet */ | ||
416 | if (rt->rt_flags&RTCF_LOCAL) { | ||
417 | ip_rt_put(rt); | ||
418 | rt = NULL; | ||
419 | fl.fl4_daddr = eiph->daddr; | ||
420 | fl.fl4_src = eiph->saddr; | ||
421 | fl.fl4_tos = eiph->tos; | ||
422 | if (ip_route_output_key(&rt, &fl) || | ||
423 | rt->u.dst.dev->type != ARPHRD_TUNNEL) { | ||
424 | ip_rt_put(rt); | ||
425 | kfree_skb(skb2); | ||
426 | return; | ||
427 | } | ||
428 | } else { | ||
429 | ip_rt_put(rt); | ||
430 | if (ip_route_input(skb2, eiph->daddr, eiph->saddr, eiph->tos, skb2->dev) || | ||
431 | skb2->dst->dev->type != ARPHRD_TUNNEL) { | ||
432 | kfree_skb(skb2); | ||
433 | return; | ||
434 | } | ||
435 | } | ||
436 | |||
437 | /* change mtu on this route */ | ||
438 | if (type == ICMP_DEST_UNREACH && code == ICMP_FRAG_NEEDED) { | ||
439 | if (rel_info > dst_mtu(skb2->dst)) { | ||
440 | kfree_skb(skb2); | ||
441 | return; | ||
442 | } | ||
443 | skb2->dst->ops->update_pmtu(skb2->dst, rel_info); | ||
444 | rel_info = htonl(rel_info); | ||
445 | } else if (type == ICMP_TIME_EXCEEDED) { | ||
446 | struct ip_tunnel *t = (struct ip_tunnel*)skb2->dev->priv; | ||
447 | if (t->parms.iph.ttl) { | ||
448 | rel_type = ICMP_DEST_UNREACH; | ||
449 | rel_code = ICMP_HOST_UNREACH; | ||
450 | } | ||
451 | } | ||
452 | |||
453 | icmp_send(skb2, rel_type, rel_code, rel_info); | ||
454 | kfree_skb(skb2); | ||
455 | return; | ||
456 | #endif | ||
457 | } | ||
458 | |||
459 | static inline void ipip_ecn_decapsulate(struct iphdr *outer_iph, struct sk_buff *skb) | ||
460 | { | ||
461 | struct iphdr *inner_iph = skb->nh.iph; | ||
462 | |||
463 | if (INET_ECN_is_ce(outer_iph->tos)) | ||
464 | IP_ECN_set_ce(inner_iph); | ||
465 | } | ||
466 | |||
467 | static int ipip_rcv(struct sk_buff *skb) | ||
468 | { | ||
469 | struct iphdr *iph; | ||
470 | struct ip_tunnel *tunnel; | ||
471 | |||
472 | if (!pskb_may_pull(skb, sizeof(struct iphdr))) | ||
473 | goto out; | ||
474 | |||
475 | iph = skb->nh.iph; | ||
476 | |||
477 | read_lock(&ipip_lock); | ||
478 | if ((tunnel = ipip_tunnel_lookup(iph->saddr, iph->daddr)) != NULL) { | ||
479 | if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb)) { | ||
480 | read_unlock(&ipip_lock); | ||
481 | kfree_skb(skb); | ||
482 | return 0; | ||
483 | } | ||
484 | |||
485 | secpath_reset(skb); | ||
486 | |||
487 | skb->mac.raw = skb->nh.raw; | ||
488 | skb->nh.raw = skb->data; | ||
489 | memset(&(IPCB(skb)->opt), 0, sizeof(struct ip_options)); | ||
490 | skb->protocol = htons(ETH_P_IP); | ||
491 | skb->pkt_type = PACKET_HOST; | ||
492 | |||
493 | tunnel->stat.rx_packets++; | ||
494 | tunnel->stat.rx_bytes += skb->len; | ||
495 | skb->dev = tunnel->dev; | ||
496 | dst_release(skb->dst); | ||
497 | skb->dst = NULL; | ||
498 | nf_reset(skb); | ||
499 | ipip_ecn_decapsulate(iph, skb); | ||
500 | netif_rx(skb); | ||
501 | read_unlock(&ipip_lock); | ||
502 | return 0; | ||
503 | } | ||
504 | read_unlock(&ipip_lock); | ||
505 | |||
506 | out: | ||
507 | return -1; | ||
508 | } | ||
509 | |||
510 | /* | ||
511 | * This function assumes it is being called from dev_queue_xmit() | ||
512 | * and that skb is filled properly by that function. | ||
513 | */ | ||
514 | |||
515 | static int ipip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev) | ||
516 | { | ||
517 | struct ip_tunnel *tunnel = (struct ip_tunnel*)dev->priv; | ||
518 | struct net_device_stats *stats = &tunnel->stat; | ||
519 | struct iphdr *tiph = &tunnel->parms.iph; | ||
520 | u8 tos = tunnel->parms.iph.tos; | ||
521 | u16 df = tiph->frag_off; | ||
522 | struct rtable *rt; /* Route to the other host */ | ||
523 | struct net_device *tdev; /* Device to other host */ | ||
524 | struct iphdr *old_iph = skb->nh.iph; | ||
525 | struct iphdr *iph; /* Our new IP header */ | ||
526 | int max_headroom; /* The extra header space needed */ | ||
527 | u32 dst = tiph->daddr; | ||
528 | int mtu; | ||
529 | |||
530 | if (tunnel->recursion++) { | ||
531 | tunnel->stat.collisions++; | ||
532 | goto tx_error; | ||
533 | } | ||
534 | |||
535 | if (skb->protocol != htons(ETH_P_IP)) | ||
536 | goto tx_error; | ||
537 | |||
538 | if (tos&1) | ||
539 | tos = old_iph->tos; | ||
540 | |||
541 | if (!dst) { | ||
542 | /* NBMA tunnel */ | ||
543 | if ((rt = (struct rtable*)skb->dst) == NULL) { | ||
544 | tunnel->stat.tx_fifo_errors++; | ||
545 | goto tx_error; | ||
546 | } | ||
547 | if ((dst = rt->rt_gateway) == 0) | ||
548 | goto tx_error_icmp; | ||
549 | } | ||
550 | |||
551 | { | ||
552 | struct flowi fl = { .oif = tunnel->parms.link, | ||
553 | .nl_u = { .ip4_u = | ||
554 | { .daddr = dst, | ||
555 | .saddr = tiph->saddr, | ||
556 | .tos = RT_TOS(tos) } }, | ||
557 | .proto = IPPROTO_IPIP }; | ||
558 | if (ip_route_output_key(&rt, &fl)) { | ||
559 | tunnel->stat.tx_carrier_errors++; | ||
560 | goto tx_error_icmp; | ||
561 | } | ||
562 | } | ||
563 | tdev = rt->u.dst.dev; | ||
564 | |||
565 | if (tdev == dev) { | ||
566 | ip_rt_put(rt); | ||
567 | tunnel->stat.collisions++; | ||
568 | goto tx_error; | ||
569 | } | ||
570 | |||
571 | if (tiph->frag_off) | ||
572 | mtu = dst_mtu(&rt->u.dst) - sizeof(struct iphdr); | ||
573 | else | ||
574 | mtu = skb->dst ? dst_mtu(skb->dst) : dev->mtu; | ||
575 | |||
576 | if (mtu < 68) { | ||
577 | tunnel->stat.collisions++; | ||
578 | ip_rt_put(rt); | ||
579 | goto tx_error; | ||
580 | } | ||
581 | if (skb->dst) | ||
582 | skb->dst->ops->update_pmtu(skb->dst, mtu); | ||
583 | |||
584 | df |= (old_iph->frag_off&htons(IP_DF)); | ||
585 | |||
586 | if ((old_iph->frag_off&htons(IP_DF)) && mtu < ntohs(old_iph->tot_len)) { | ||
587 | icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, htonl(mtu)); | ||
588 | ip_rt_put(rt); | ||
589 | goto tx_error; | ||
590 | } | ||
591 | |||
592 | if (tunnel->err_count > 0) { | ||
593 | if (jiffies - tunnel->err_time < IPTUNNEL_ERR_TIMEO) { | ||
594 | tunnel->err_count--; | ||
595 | dst_link_failure(skb); | ||
596 | } else | ||
597 | tunnel->err_count = 0; | ||
598 | } | ||
599 | |||
600 | /* | ||
601 | * Okay, now see if we can stuff it in the buffer as-is. | ||
602 | */ | ||
603 | max_headroom = (LL_RESERVED_SPACE(tdev)+sizeof(struct iphdr)); | ||
604 | |||
605 | if (skb_headroom(skb) < max_headroom || skb_cloned(skb) || skb_shared(skb)) { | ||
606 | struct sk_buff *new_skb = skb_realloc_headroom(skb, max_headroom); | ||
607 | if (!new_skb) { | ||
608 | ip_rt_put(rt); | ||
609 | stats->tx_dropped++; | ||
610 | dev_kfree_skb(skb); | ||
611 | tunnel->recursion--; | ||
612 | return 0; | ||
613 | } | ||
614 | if (skb->sk) | ||
615 | skb_set_owner_w(new_skb, skb->sk); | ||
616 | dev_kfree_skb(skb); | ||
617 | skb = new_skb; | ||
618 | old_iph = skb->nh.iph; | ||
619 | } | ||
620 | |||
621 | skb->h.raw = skb->nh.raw; | ||
622 | skb->nh.raw = skb_push(skb, sizeof(struct iphdr)); | ||
623 | memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt)); | ||
624 | dst_release(skb->dst); | ||
625 | skb->dst = &rt->u.dst; | ||
626 | |||
627 | /* | ||
628 | * Push down and install the IPIP header. | ||
629 | */ | ||
630 | |||
631 | iph = skb->nh.iph; | ||
632 | iph->version = 4; | ||
633 | iph->ihl = sizeof(struct iphdr)>>2; | ||
634 | iph->frag_off = df; | ||
635 | iph->protocol = IPPROTO_IPIP; | ||
636 | iph->tos = INET_ECN_encapsulate(tos, old_iph->tos); | ||
637 | iph->daddr = rt->rt_dst; | ||
638 | iph->saddr = rt->rt_src; | ||
639 | |||
640 | if ((iph->ttl = tiph->ttl) == 0) | ||
641 | iph->ttl = old_iph->ttl; | ||
642 | |||
643 | nf_reset(skb); | ||
644 | |||
645 | IPTUNNEL_XMIT(); | ||
646 | tunnel->recursion--; | ||
647 | return 0; | ||
648 | |||
649 | tx_error_icmp: | ||
650 | dst_link_failure(skb); | ||
651 | tx_error: | ||
652 | stats->tx_errors++; | ||
653 | dev_kfree_skb(skb); | ||
654 | tunnel->recursion--; | ||
655 | return 0; | ||
656 | } | ||
657 | |||
658 | static int | ||
659 | ipip_tunnel_ioctl (struct net_device *dev, struct ifreq *ifr, int cmd) | ||
660 | { | ||
661 | int err = 0; | ||
662 | struct ip_tunnel_parm p; | ||
663 | struct ip_tunnel *t; | ||
664 | |||
665 | switch (cmd) { | ||
666 | case SIOCGETTUNNEL: | ||
667 | t = NULL; | ||
668 | if (dev == ipip_fb_tunnel_dev) { | ||
669 | if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) { | ||
670 | err = -EFAULT; | ||
671 | break; | ||
672 | } | ||
673 | t = ipip_tunnel_locate(&p, 0); | ||
674 | } | ||
675 | if (t == NULL) | ||
676 | t = (struct ip_tunnel*)dev->priv; | ||
677 | memcpy(&p, &t->parms, sizeof(p)); | ||
678 | if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p))) | ||
679 | err = -EFAULT; | ||
680 | break; | ||
681 | |||
682 | case SIOCADDTUNNEL: | ||
683 | case SIOCCHGTUNNEL: | ||
684 | err = -EPERM; | ||
685 | if (!capable(CAP_NET_ADMIN)) | ||
686 | goto done; | ||
687 | |||
688 | err = -EFAULT; | ||
689 | if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) | ||
690 | goto done; | ||
691 | |||
692 | err = -EINVAL; | ||
693 | if (p.iph.version != 4 || p.iph.protocol != IPPROTO_IPIP || | ||
694 | p.iph.ihl != 5 || (p.iph.frag_off&htons(~IP_DF))) | ||
695 | goto done; | ||
696 | if (p.iph.ttl) | ||
697 | p.iph.frag_off |= htons(IP_DF); | ||
698 | |||
699 | t = ipip_tunnel_locate(&p, cmd == SIOCADDTUNNEL); | ||
700 | |||
701 | if (dev != ipip_fb_tunnel_dev && cmd == SIOCCHGTUNNEL) { | ||
702 | if (t != NULL) { | ||
703 | if (t->dev != dev) { | ||
704 | err = -EEXIST; | ||
705 | break; | ||
706 | } | ||
707 | } else { | ||
708 | if (((dev->flags&IFF_POINTOPOINT) && !p.iph.daddr) || | ||
709 | (!(dev->flags&IFF_POINTOPOINT) && p.iph.daddr)) { | ||
710 | err = -EINVAL; | ||
711 | break; | ||
712 | } | ||
713 | t = (struct ip_tunnel*)dev->priv; | ||
714 | ipip_tunnel_unlink(t); | ||
715 | t->parms.iph.saddr = p.iph.saddr; | ||
716 | t->parms.iph.daddr = p.iph.daddr; | ||
717 | memcpy(dev->dev_addr, &p.iph.saddr, 4); | ||
718 | memcpy(dev->broadcast, &p.iph.daddr, 4); | ||
719 | ipip_tunnel_link(t); | ||
720 | netdev_state_change(dev); | ||
721 | } | ||
722 | } | ||
723 | |||
724 | if (t) { | ||
725 | err = 0; | ||
726 | if (cmd == SIOCCHGTUNNEL) { | ||
727 | t->parms.iph.ttl = p.iph.ttl; | ||
728 | t->parms.iph.tos = p.iph.tos; | ||
729 | t->parms.iph.frag_off = p.iph.frag_off; | ||
730 | } | ||
731 | if (copy_to_user(ifr->ifr_ifru.ifru_data, &t->parms, sizeof(p))) | ||
732 | err = -EFAULT; | ||
733 | } else | ||
734 | err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT); | ||
735 | break; | ||
736 | |||
737 | case SIOCDELTUNNEL: | ||
738 | err = -EPERM; | ||
739 | if (!capable(CAP_NET_ADMIN)) | ||
740 | goto done; | ||
741 | |||
742 | if (dev == ipip_fb_tunnel_dev) { | ||
743 | err = -EFAULT; | ||
744 | if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) | ||
745 | goto done; | ||
746 | err = -ENOENT; | ||
747 | if ((t = ipip_tunnel_locate(&p, 0)) == NULL) | ||
748 | goto done; | ||
749 | err = -EPERM; | ||
750 | if (t->dev == ipip_fb_tunnel_dev) | ||
751 | goto done; | ||
752 | dev = t->dev; | ||
753 | } | ||
754 | err = unregister_netdevice(dev); | ||
755 | break; | ||
756 | |||
757 | default: | ||
758 | err = -EINVAL; | ||
759 | } | ||
760 | |||
761 | done: | ||
762 | return err; | ||
763 | } | ||
764 | |||
765 | static struct net_device_stats *ipip_tunnel_get_stats(struct net_device *dev) | ||
766 | { | ||
767 | return &(((struct ip_tunnel*)dev->priv)->stat); | ||
768 | } | ||
769 | |||
770 | static int ipip_tunnel_change_mtu(struct net_device *dev, int new_mtu) | ||
771 | { | ||
772 | if (new_mtu < 68 || new_mtu > 0xFFF8 - sizeof(struct iphdr)) | ||
773 | return -EINVAL; | ||
774 | dev->mtu = new_mtu; | ||
775 | return 0; | ||
776 | } | ||
777 | |||
778 | static void ipip_tunnel_setup(struct net_device *dev) | ||
779 | { | ||
780 | SET_MODULE_OWNER(dev); | ||
781 | dev->uninit = ipip_tunnel_uninit; | ||
782 | dev->hard_start_xmit = ipip_tunnel_xmit; | ||
783 | dev->get_stats = ipip_tunnel_get_stats; | ||
784 | dev->do_ioctl = ipip_tunnel_ioctl; | ||
785 | dev->change_mtu = ipip_tunnel_change_mtu; | ||
786 | dev->destructor = free_netdev; | ||
787 | |||
788 | dev->type = ARPHRD_TUNNEL; | ||
789 | dev->hard_header_len = LL_MAX_HEADER + sizeof(struct iphdr); | ||
790 | dev->mtu = 1500 - sizeof(struct iphdr); | ||
791 | dev->flags = IFF_NOARP; | ||
792 | dev->iflink = 0; | ||
793 | dev->addr_len = 4; | ||
794 | } | ||
795 | |||
796 | static int ipip_tunnel_init(struct net_device *dev) | ||
797 | { | ||
798 | struct net_device *tdev = NULL; | ||
799 | struct ip_tunnel *tunnel; | ||
800 | struct iphdr *iph; | ||
801 | |||
802 | tunnel = (struct ip_tunnel*)dev->priv; | ||
803 | iph = &tunnel->parms.iph; | ||
804 | |||
805 | tunnel->dev = dev; | ||
806 | strcpy(tunnel->parms.name, dev->name); | ||
807 | |||
808 | memcpy(dev->dev_addr, &tunnel->parms.iph.saddr, 4); | ||
809 | memcpy(dev->broadcast, &tunnel->parms.iph.daddr, 4); | ||
810 | |||
811 | if (iph->daddr) { | ||
812 | struct flowi fl = { .oif = tunnel->parms.link, | ||
813 | .nl_u = { .ip4_u = | ||
814 | { .daddr = iph->daddr, | ||
815 | .saddr = iph->saddr, | ||
816 | .tos = RT_TOS(iph->tos) } }, | ||
817 | .proto = IPPROTO_IPIP }; | ||
818 | struct rtable *rt; | ||
819 | if (!ip_route_output_key(&rt, &fl)) { | ||
820 | tdev = rt->u.dst.dev; | ||
821 | ip_rt_put(rt); | ||
822 | } | ||
823 | dev->flags |= IFF_POINTOPOINT; | ||
824 | } | ||
825 | |||
826 | if (!tdev && tunnel->parms.link) | ||
827 | tdev = __dev_get_by_index(tunnel->parms.link); | ||
828 | |||
829 | if (tdev) { | ||
830 | dev->hard_header_len = tdev->hard_header_len + sizeof(struct iphdr); | ||
831 | dev->mtu = tdev->mtu - sizeof(struct iphdr); | ||
832 | } | ||
833 | dev->iflink = tunnel->parms.link; | ||
834 | |||
835 | return 0; | ||
836 | } | ||
837 | |||
838 | static int __init ipip_fb_tunnel_init(struct net_device *dev) | ||
839 | { | ||
840 | struct ip_tunnel *tunnel = dev->priv; | ||
841 | struct iphdr *iph = &tunnel->parms.iph; | ||
842 | |||
843 | tunnel->dev = dev; | ||
844 | strcpy(tunnel->parms.name, dev->name); | ||
845 | |||
846 | iph->version = 4; | ||
847 | iph->protocol = IPPROTO_IPIP; | ||
848 | iph->ihl = 5; | ||
849 | |||
850 | dev_hold(dev); | ||
851 | tunnels_wc[0] = tunnel; | ||
852 | return 0; | ||
853 | } | ||
854 | |||
855 | static struct xfrm_tunnel ipip_handler = { | ||
856 | .handler = ipip_rcv, | ||
857 | .err_handler = ipip_err, | ||
858 | }; | ||
859 | |||
860 | static char banner[] __initdata = | ||
861 | KERN_INFO "IPv4 over IPv4 tunneling driver\n"; | ||
862 | |||
863 | static int __init ipip_init(void) | ||
864 | { | ||
865 | int err; | ||
866 | |||
867 | printk(banner); | ||
868 | |||
869 | if (xfrm4_tunnel_register(&ipip_handler) < 0) { | ||
870 | printk(KERN_INFO "ipip init: can't register tunnel\n"); | ||
871 | return -EAGAIN; | ||
872 | } | ||
873 | |||
874 | ipip_fb_tunnel_dev = alloc_netdev(sizeof(struct ip_tunnel), | ||
875 | "tunl0", | ||
876 | ipip_tunnel_setup); | ||
877 | if (!ipip_fb_tunnel_dev) { | ||
878 | err = -ENOMEM; | ||
879 | goto err1; | ||
880 | } | ||
881 | |||
882 | ipip_fb_tunnel_dev->init = ipip_fb_tunnel_init; | ||
883 | |||
884 | if ((err = register_netdev(ipip_fb_tunnel_dev))) | ||
885 | goto err2; | ||
886 | out: | ||
887 | return err; | ||
888 | err2: | ||
889 | free_netdev(ipip_fb_tunnel_dev); | ||
890 | err1: | ||
891 | xfrm4_tunnel_deregister(&ipip_handler); | ||
892 | goto out; | ||
893 | } | ||
894 | |||
895 | static void __exit ipip_fini(void) | ||
896 | { | ||
897 | if (xfrm4_tunnel_deregister(&ipip_handler) < 0) | ||
898 | printk(KERN_INFO "ipip close: can't deregister tunnel\n"); | ||
899 | |||
900 | unregister_netdev(ipip_fb_tunnel_dev); | ||
901 | } | ||
902 | |||
903 | module_init(ipip_init); | ||
904 | module_exit(ipip_fini); | ||
905 | MODULE_LICENSE("GPL"); | ||