Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * IPv6 over IPv4 tunnel device - Simple Internet Transition (SIT) | |
3 | * Linux INET6 implementation | |
4 | * | |
5 | * Authors: | |
1ab1457c | 6 | * Pedro Roque <roque@di.fc.ul.pt> |
1da177e4 LT |
7 | * Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> |
8 | * | |
9 | * $Id: sit.c,v 1.53 2001/09/25 05:09:53 davem Exp $ | |
10 | * | |
11 | * This program is free software; you can redistribute it and/or | |
12 | * modify it under the terms of the GNU General Public License | |
13 | * as published by the Free Software Foundation; either version | |
14 | * 2 of the License, or (at your option) any later version. | |
15 | * | |
16 | * Changes: | |
17 | * Roger Venning <r.venning@telstra.com>: 6to4 support | |
18 | * Nate Thompson <nate@thebog.net>: 6to4 support | |
19 | */ | |
20 | ||
1da177e4 | 21 | #include <linux/module.h> |
4fc268d2 | 22 | #include <linux/capability.h> |
1da177e4 LT |
23 | #include <linux/errno.h> |
24 | #include <linux/types.h> | |
25 | #include <linux/socket.h> | |
26 | #include <linux/sockios.h> | |
1da177e4 LT |
27 | #include <linux/net.h> |
28 | #include <linux/in6.h> | |
29 | #include <linux/netdevice.h> | |
30 | #include <linux/if_arp.h> | |
31 | #include <linux/icmp.h> | |
32 | #include <asm/uaccess.h> | |
33 | #include <linux/init.h> | |
34 | #include <linux/netfilter_ipv4.h> | |
46f25dff | 35 | #include <linux/if_ether.h> |
1da177e4 LT |
36 | |
37 | #include <net/sock.h> | |
38 | #include <net/snmp.h> | |
39 | ||
40 | #include <net/ipv6.h> | |
41 | #include <net/protocol.h> | |
42 | #include <net/transp_v6.h> | |
43 | #include <net/ip6_fib.h> | |
44 | #include <net/ip6_route.h> | |
45 | #include <net/ndisc.h> | |
46 | #include <net/addrconf.h> | |
47 | #include <net/ip.h> | |
48 | #include <net/udp.h> | |
49 | #include <net/icmp.h> | |
50 | #include <net/ipip.h> | |
51 | #include <net/inet_ecn.h> | |
52 | #include <net/xfrm.h> | |
53 | #include <net/dsfield.h> | |
54 | ||
55 | /* | |
56 | This version of net/ipv6/sit.c is cloned of net/ipv4/ip_gre.c | |
57 | ||
58 | For comments look at net/ipv4/ip_gre.c --ANK | |
59 | */ | |
60 | ||
61 | #define HASH_SIZE 16 | |
e69a4adc | 62 | #define HASH(addr) (((__force u32)addr^((__force u32)addr>>4))&0xF) |
1da177e4 LT |
63 | |
64 | static int ipip6_fb_tunnel_init(struct net_device *dev); | |
65 | static int ipip6_tunnel_init(struct net_device *dev); | |
66 | static void ipip6_tunnel_setup(struct net_device *dev); | |
67 | ||
68 | static struct net_device *ipip6_fb_tunnel_dev; | |
69 | ||
70 | static struct ip_tunnel *tunnels_r_l[HASH_SIZE]; | |
71 | static struct ip_tunnel *tunnels_r[HASH_SIZE]; | |
72 | static struct ip_tunnel *tunnels_l[HASH_SIZE]; | |
73 | static struct ip_tunnel *tunnels_wc[1]; | |
74 | static struct ip_tunnel **tunnels[4] = { tunnels_wc, tunnels_l, tunnels_r, tunnels_r_l }; | |
75 | ||
76 | static DEFINE_RWLOCK(ipip6_lock); | |
77 | ||
e69a4adc | 78 | static struct ip_tunnel * ipip6_tunnel_lookup(__be32 remote, __be32 local) |
1da177e4 LT |
79 | { |
80 | unsigned h0 = HASH(remote); | |
81 | unsigned h1 = HASH(local); | |
82 | struct ip_tunnel *t; | |
83 | ||
84 | for (t = tunnels_r_l[h0^h1]; t; t = t->next) { | |
85 | if (local == t->parms.iph.saddr && | |
86 | remote == t->parms.iph.daddr && (t->dev->flags&IFF_UP)) | |
87 | return t; | |
88 | } | |
89 | for (t = tunnels_r[h0]; t; t = t->next) { | |
90 | if (remote == t->parms.iph.daddr && (t->dev->flags&IFF_UP)) | |
91 | return t; | |
92 | } | |
93 | for (t = tunnels_l[h1]; t; t = t->next) { | |
94 | if (local == t->parms.iph.saddr && (t->dev->flags&IFF_UP)) | |
95 | return t; | |
96 | } | |
97 | if ((t = tunnels_wc[0]) != NULL && (t->dev->flags&IFF_UP)) | |
98 | return t; | |
99 | return NULL; | |
100 | } | |
101 | ||
420fe234 | 102 | static struct ip_tunnel **__ipip6_bucket(struct ip_tunnel_parm *parms) |
1da177e4 | 103 | { |
420fe234 YH |
104 | __be32 remote = parms->iph.daddr; |
105 | __be32 local = parms->iph.saddr; | |
1da177e4 LT |
106 | unsigned h = 0; |
107 | int prio = 0; | |
108 | ||
109 | if (remote) { | |
110 | prio |= 2; | |
111 | h ^= HASH(remote); | |
112 | } | |
113 | if (local) { | |
114 | prio |= 1; | |
115 | h ^= HASH(local); | |
116 | } | |
117 | return &tunnels[prio][h]; | |
118 | } | |
119 | ||
420fe234 YH |
120 | static inline struct ip_tunnel **ipip6_bucket(struct ip_tunnel *t) |
121 | { | |
122 | return __ipip6_bucket(&t->parms); | |
123 | } | |
124 | ||
1da177e4 LT |
125 | static void ipip6_tunnel_unlink(struct ip_tunnel *t) |
126 | { | |
127 | struct ip_tunnel **tp; | |
128 | ||
129 | for (tp = ipip6_bucket(t); *tp; tp = &(*tp)->next) { | |
130 | if (t == *tp) { | |
131 | write_lock_bh(&ipip6_lock); | |
132 | *tp = t->next; | |
133 | write_unlock_bh(&ipip6_lock); | |
134 | break; | |
135 | } | |
136 | } | |
137 | } | |
138 | ||
139 | static void ipip6_tunnel_link(struct ip_tunnel *t) | |
140 | { | |
141 | struct ip_tunnel **tp = ipip6_bucket(t); | |
142 | ||
143 | t->next = *tp; | |
144 | write_lock_bh(&ipip6_lock); | |
145 | *tp = t; | |
146 | write_unlock_bh(&ipip6_lock); | |
147 | } | |
148 | ||
149 | static struct ip_tunnel * ipip6_tunnel_locate(struct ip_tunnel_parm *parms, int create) | |
150 | { | |
e69a4adc AV |
151 | __be32 remote = parms->iph.daddr; |
152 | __be32 local = parms->iph.saddr; | |
1da177e4 LT |
153 | struct ip_tunnel *t, **tp, *nt; |
154 | struct net_device *dev; | |
1da177e4 LT |
155 | char name[IFNAMSIZ]; |
156 | ||
420fe234 | 157 | for (tp = __ipip6_bucket(parms); (t = *tp) != NULL; tp = &t->next) { |
1da177e4 LT |
158 | if (local == t->parms.iph.saddr && remote == t->parms.iph.daddr) |
159 | return t; | |
160 | } | |
161 | if (!create) | |
162 | goto failed; | |
163 | ||
164 | if (parms->name[0]) | |
165 | strlcpy(name, parms->name, IFNAMSIZ); | |
166 | else { | |
167 | int i; | |
168 | for (i=1; i<100; i++) { | |
169 | sprintf(name, "sit%d", i); | |
881d966b | 170 | if (__dev_get_by_name(&init_net, name) == NULL) |
1da177e4 LT |
171 | break; |
172 | } | |
173 | if (i==100) | |
174 | goto failed; | |
175 | } | |
176 | ||
177 | dev = alloc_netdev(sizeof(*t), name, ipip6_tunnel_setup); | |
178 | if (dev == NULL) | |
179 | return NULL; | |
180 | ||
2941a486 | 181 | nt = netdev_priv(dev); |
1da177e4 LT |
182 | dev->init = ipip6_tunnel_init; |
183 | nt->parms = *parms; | |
184 | ||
185 | if (register_netdevice(dev) < 0) { | |
186 | free_netdev(dev); | |
187 | goto failed; | |
188 | } | |
189 | ||
190 | dev_hold(dev); | |
191 | ||
192 | ipip6_tunnel_link(nt); | |
1da177e4 LT |
193 | return nt; |
194 | ||
195 | failed: | |
196 | return NULL; | |
197 | } | |
198 | ||
199 | static void ipip6_tunnel_uninit(struct net_device *dev) | |
200 | { | |
201 | if (dev == ipip6_fb_tunnel_dev) { | |
202 | write_lock_bh(&ipip6_lock); | |
203 | tunnels_wc[0] = NULL; | |
204 | write_unlock_bh(&ipip6_lock); | |
205 | dev_put(dev); | |
206 | } else { | |
2941a486 | 207 | ipip6_tunnel_unlink(netdev_priv(dev)); |
1da177e4 LT |
208 | dev_put(dev); |
209 | } | |
210 | } | |
211 | ||
212 | ||
c73cb5a2 | 213 | static int ipip6_err(struct sk_buff *skb, u32 info) |
1da177e4 LT |
214 | { |
215 | #ifndef I_WISH_WORLD_WERE_PERFECT | |
216 | ||
217 | /* It is not :-( All the routers (except for Linux) return only | |
218 | 8 bytes of packet payload. It means, that precise relaying of | |
219 | ICMP in the real Internet is absolutely infeasible. | |
220 | */ | |
221 | struct iphdr *iph = (struct iphdr*)skb->data; | |
88c7664f ACM |
222 | const int type = icmp_hdr(skb)->type; |
223 | const int code = icmp_hdr(skb)->code; | |
1da177e4 | 224 | struct ip_tunnel *t; |
c73cb5a2 | 225 | int err; |
1da177e4 LT |
226 | |
227 | switch (type) { | |
228 | default: | |
229 | case ICMP_PARAMETERPROB: | |
c73cb5a2 | 230 | return 0; |
1da177e4 LT |
231 | |
232 | case ICMP_DEST_UNREACH: | |
233 | switch (code) { | |
234 | case ICMP_SR_FAILED: | |
235 | case ICMP_PORT_UNREACH: | |
236 | /* Impossible event. */ | |
c73cb5a2 | 237 | return 0; |
1da177e4 LT |
238 | case ICMP_FRAG_NEEDED: |
239 | /* Soft state for pmtu is maintained by IP core. */ | |
c73cb5a2 | 240 | return 0; |
1da177e4 LT |
241 | default: |
242 | /* All others are translated to HOST_UNREACH. | |
243 | rfc2003 contains "deep thoughts" about NET_UNREACH, | |
244 | I believe they are just ether pollution. --ANK | |
245 | */ | |
246 | break; | |
247 | } | |
248 | break; | |
249 | case ICMP_TIME_EXCEEDED: | |
250 | if (code != ICMP_EXC_TTL) | |
c73cb5a2 | 251 | return 0; |
1da177e4 LT |
252 | break; |
253 | } | |
254 | ||
c73cb5a2 KM |
255 | err = -ENOENT; |
256 | ||
1da177e4 LT |
257 | read_lock(&ipip6_lock); |
258 | t = ipip6_tunnel_lookup(iph->daddr, iph->saddr); | |
259 | if (t == NULL || t->parms.iph.daddr == 0) | |
260 | goto out; | |
c73cb5a2 KM |
261 | |
262 | err = 0; | |
1da177e4 LT |
263 | if (t->parms.iph.ttl == 0 && type == ICMP_TIME_EXCEEDED) |
264 | goto out; | |
265 | ||
266 | if (jiffies - t->err_time < IPTUNNEL_ERR_TIMEO) | |
267 | t->err_count++; | |
268 | else | |
269 | t->err_count = 1; | |
270 | t->err_time = jiffies; | |
271 | out: | |
272 | read_unlock(&ipip6_lock); | |
c73cb5a2 | 273 | return err; |
1da177e4 LT |
274 | #else |
275 | struct iphdr *iph = (struct iphdr*)dp; | |
276 | int hlen = iph->ihl<<2; | |
277 | struct ipv6hdr *iph6; | |
88c7664f ACM |
278 | const int type = icmp_hdr(skb)->type; |
279 | const int code = icmp_hdr(skb)->code; | |
1da177e4 LT |
280 | int rel_type = 0; |
281 | int rel_code = 0; | |
282 | int rel_info = 0; | |
283 | struct sk_buff *skb2; | |
284 | struct rt6_info *rt6i; | |
285 | ||
286 | if (len < hlen + sizeof(struct ipv6hdr)) | |
287 | return; | |
288 | iph6 = (struct ipv6hdr*)(dp + hlen); | |
289 | ||
290 | switch (type) { | |
291 | default: | |
292 | return; | |
293 | case ICMP_PARAMETERPROB: | |
88c7664f | 294 | if (icmp_hdr(skb)->un.gateway < hlen) |
1da177e4 LT |
295 | return; |
296 | ||
297 | /* So... This guy found something strange INSIDE encapsulated | |
298 | packet. Well, he is fool, but what can we do ? | |
299 | */ | |
300 | rel_type = ICMPV6_PARAMPROB; | |
88c7664f | 301 | rel_info = icmp_hdr(skb)->un.gateway - hlen; |
1da177e4 LT |
302 | break; |
303 | ||
304 | case ICMP_DEST_UNREACH: | |
305 | switch (code) { | |
306 | case ICMP_SR_FAILED: | |
307 | case ICMP_PORT_UNREACH: | |
308 | /* Impossible event. */ | |
309 | return; | |
310 | case ICMP_FRAG_NEEDED: | |
311 | /* Too complicated case ... */ | |
312 | return; | |
313 | default: | |
314 | /* All others are translated to HOST_UNREACH. | |
315 | rfc2003 contains "deep thoughts" about NET_UNREACH, | |
316 | I believe, it is just ether pollution. --ANK | |
317 | */ | |
318 | rel_type = ICMPV6_DEST_UNREACH; | |
319 | rel_code = ICMPV6_ADDR_UNREACH; | |
320 | break; | |
321 | } | |
322 | break; | |
323 | case ICMP_TIME_EXCEEDED: | |
324 | if (code != ICMP_EXC_TTL) | |
325 | return; | |
326 | rel_type = ICMPV6_TIME_EXCEED; | |
327 | rel_code = ICMPV6_EXC_HOPLIMIT; | |
328 | break; | |
329 | } | |
330 | ||
331 | /* Prepare fake skb to feed it to icmpv6_send */ | |
332 | skb2 = skb_clone(skb, GFP_ATOMIC); | |
333 | if (skb2 == NULL) | |
c73cb5a2 | 334 | return 0; |
1da177e4 LT |
335 | dst_release(skb2->dst); |
336 | skb2->dst = NULL; | |
337 | skb_pull(skb2, skb->data - (u8*)iph6); | |
c1d2bbe1 | 338 | skb_reset_network_header(skb2); |
1da177e4 LT |
339 | |
340 | /* Try to guess incoming interface */ | |
341 | rt6i = rt6_lookup(&iph6->saddr, NULL, NULL, 0); | |
342 | if (rt6i && rt6i->rt6i_dev) { | |
343 | skb2->dev = rt6i->rt6i_dev; | |
344 | ||
345 | rt6i = rt6_lookup(&iph6->daddr, &iph6->saddr, NULL, 0); | |
346 | ||
347 | if (rt6i && rt6i->rt6i_dev && rt6i->rt6i_dev->type == ARPHRD_SIT) { | |
2941a486 | 348 | struct ip_tunnel *t = netdev_priv(rt6i->rt6i_dev); |
1da177e4 LT |
349 | if (rel_type == ICMPV6_TIME_EXCEED && t->parms.iph.ttl) { |
350 | rel_type = ICMPV6_DEST_UNREACH; | |
351 | rel_code = ICMPV6_ADDR_UNREACH; | |
352 | } | |
353 | icmpv6_send(skb2, rel_type, rel_code, rel_info, skb2->dev); | |
354 | } | |
355 | } | |
356 | kfree_skb(skb2); | |
c73cb5a2 | 357 | return 0; |
1da177e4 LT |
358 | #endif |
359 | } | |
360 | ||
361 | static inline void ipip6_ecn_decapsulate(struct iphdr *iph, struct sk_buff *skb) | |
362 | { | |
363 | if (INET_ECN_is_ce(iph->tos)) | |
0660e03f | 364 | IP6_ECN_set_ce(ipv6_hdr(skb)); |
1da177e4 LT |
365 | } |
366 | ||
367 | static int ipip6_rcv(struct sk_buff *skb) | |
368 | { | |
369 | struct iphdr *iph; | |
370 | struct ip_tunnel *tunnel; | |
371 | ||
372 | if (!pskb_may_pull(skb, sizeof(struct ipv6hdr))) | |
373 | goto out; | |
374 | ||
eddc9ec5 | 375 | iph = ip_hdr(skb); |
1da177e4 LT |
376 | |
377 | read_lock(&ipip6_lock); | |
378 | if ((tunnel = ipip6_tunnel_lookup(iph->saddr, iph->daddr)) != NULL) { | |
379 | secpath_reset(skb); | |
b0e380b1 | 380 | skb->mac_header = skb->network_header; |
c1d2bbe1 | 381 | skb_reset_network_header(skb); |
8cdfab8a | 382 | IPCB(skb)->flags = 0; |
1da177e4 LT |
383 | skb->protocol = htons(ETH_P_IPV6); |
384 | skb->pkt_type = PACKET_HOST; | |
385 | tunnel->stat.rx_packets++; | |
386 | tunnel->stat.rx_bytes += skb->len; | |
387 | skb->dev = tunnel->dev; | |
388 | dst_release(skb->dst); | |
389 | skb->dst = NULL; | |
390 | nf_reset(skb); | |
391 | ipip6_ecn_decapsulate(iph, skb); | |
392 | netif_rx(skb); | |
393 | read_unlock(&ipip6_lock); | |
394 | return 0; | |
395 | } | |
396 | ||
45af08be | 397 | icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PORT_UNREACH, 0); |
1da177e4 LT |
398 | kfree_skb(skb); |
399 | read_unlock(&ipip6_lock); | |
400 | out: | |
401 | return 0; | |
402 | } | |
403 | ||
404 | /* Returns the embedded IPv4 address if the IPv6 address | |
405 | comes from 6to4 (RFC 3056) addr space */ | |
406 | ||
e69a4adc | 407 | static inline __be32 try_6to4(struct in6_addr *v6dst) |
1da177e4 | 408 | { |
e69a4adc | 409 | __be32 dst = 0; |
1da177e4 LT |
410 | |
411 | if (v6dst->s6_addr16[0] == htons(0x2002)) { | |
1ab1457c | 412 | /* 6to4 v6 addr has 16 bits prefix, 32 v4addr, 16 SLA, ... */ |
1da177e4 LT |
413 | memcpy(&dst, &v6dst->s6_addr16[1], 4); |
414 | } | |
415 | return dst; | |
416 | } | |
417 | ||
418 | /* | |
419 | * This function assumes it is being called from dev_queue_xmit() | |
420 | * and that skb is filled properly by that function. | |
421 | */ | |
422 | ||
423 | static int ipip6_tunnel_xmit(struct sk_buff *skb, struct net_device *dev) | |
424 | { | |
2941a486 | 425 | struct ip_tunnel *tunnel = netdev_priv(dev); |
1da177e4 LT |
426 | struct net_device_stats *stats = &tunnel->stat; |
427 | struct iphdr *tiph = &tunnel->parms.iph; | |
0660e03f | 428 | struct ipv6hdr *iph6 = ipv6_hdr(skb); |
1da177e4 LT |
429 | u8 tos = tunnel->parms.iph.tos; |
430 | struct rtable *rt; /* Route to the other host */ | |
431 | struct net_device *tdev; /* Device to other host */ | |
432 | struct iphdr *iph; /* Our new IP header */ | |
c2636b4d | 433 | unsigned int max_headroom; /* The extra header space needed */ |
e69a4adc | 434 | __be32 dst = tiph->daddr; |
1da177e4 | 435 | int mtu; |
1ab1457c | 436 | struct in6_addr *addr6; |
1da177e4 LT |
437 | int addr_type; |
438 | ||
439 | if (tunnel->recursion++) { | |
440 | tunnel->stat.collisions++; | |
441 | goto tx_error; | |
442 | } | |
443 | ||
444 | if (skb->protocol != htons(ETH_P_IPV6)) | |
445 | goto tx_error; | |
446 | ||
447 | if (!dst) | |
448 | dst = try_6to4(&iph6->daddr); | |
449 | ||
450 | if (!dst) { | |
451 | struct neighbour *neigh = NULL; | |
452 | ||
453 | if (skb->dst) | |
454 | neigh = skb->dst->neighbour; | |
455 | ||
456 | if (neigh == NULL) { | |
457 | if (net_ratelimit()) | |
458 | printk(KERN_DEBUG "sit: nexthop == NULL\n"); | |
459 | goto tx_error; | |
460 | } | |
461 | ||
462 | addr6 = (struct in6_addr*)&neigh->primary_key; | |
463 | addr_type = ipv6_addr_type(addr6); | |
464 | ||
465 | if (addr_type == IPV6_ADDR_ANY) { | |
0660e03f | 466 | addr6 = &ipv6_hdr(skb)->daddr; |
1da177e4 LT |
467 | addr_type = ipv6_addr_type(addr6); |
468 | } | |
469 | ||
470 | if ((addr_type & IPV6_ADDR_COMPATv4) == 0) | |
471 | goto tx_error_icmp; | |
472 | ||
473 | dst = addr6->s6_addr32[3]; | |
474 | } | |
475 | ||
476 | { | |
477 | struct flowi fl = { .nl_u = { .ip4_u = | |
478 | { .daddr = dst, | |
479 | .saddr = tiph->saddr, | |
480 | .tos = RT_TOS(tos) } }, | |
481 | .oif = tunnel->parms.link, | |
482 | .proto = IPPROTO_IPV6 }; | |
483 | if (ip_route_output_key(&rt, &fl)) { | |
484 | tunnel->stat.tx_carrier_errors++; | |
485 | goto tx_error_icmp; | |
486 | } | |
487 | } | |
488 | if (rt->rt_type != RTN_UNICAST) { | |
489 | ip_rt_put(rt); | |
490 | tunnel->stat.tx_carrier_errors++; | |
491 | goto tx_error_icmp; | |
492 | } | |
493 | tdev = rt->u.dst.dev; | |
494 | ||
495 | if (tdev == dev) { | |
496 | ip_rt_put(rt); | |
497 | tunnel->stat.collisions++; | |
498 | goto tx_error; | |
499 | } | |
500 | ||
501 | if (tiph->frag_off) | |
502 | mtu = dst_mtu(&rt->u.dst) - sizeof(struct iphdr); | |
503 | else | |
504 | mtu = skb->dst ? dst_mtu(skb->dst) : dev->mtu; | |
505 | ||
506 | if (mtu < 68) { | |
507 | tunnel->stat.collisions++; | |
508 | ip_rt_put(rt); | |
509 | goto tx_error; | |
510 | } | |
511 | if (mtu < IPV6_MIN_MTU) | |
512 | mtu = IPV6_MIN_MTU; | |
513 | if (tunnel->parms.iph.daddr && skb->dst) | |
514 | skb->dst->ops->update_pmtu(skb->dst, mtu); | |
515 | ||
516 | if (skb->len > mtu) { | |
517 | icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu, dev); | |
518 | ip_rt_put(rt); | |
519 | goto tx_error; | |
520 | } | |
521 | ||
522 | if (tunnel->err_count > 0) { | |
523 | if (jiffies - tunnel->err_time < IPTUNNEL_ERR_TIMEO) { | |
524 | tunnel->err_count--; | |
525 | dst_link_failure(skb); | |
526 | } else | |
527 | tunnel->err_count = 0; | |
528 | } | |
529 | ||
530 | /* | |
531 | * Okay, now see if we can stuff it in the buffer as-is. | |
532 | */ | |
533 | max_headroom = LL_RESERVED_SPACE(tdev)+sizeof(struct iphdr); | |
534 | ||
cfbba49d PM |
535 | if (skb_headroom(skb) < max_headroom || skb_shared(skb) || |
536 | (skb_cloned(skb) && !skb_clone_writable(skb, 0))) { | |
1da177e4 LT |
537 | struct sk_buff *new_skb = skb_realloc_headroom(skb, max_headroom); |
538 | if (!new_skb) { | |
539 | ip_rt_put(rt); | |
1ab1457c | 540 | stats->tx_dropped++; |
1da177e4 LT |
541 | dev_kfree_skb(skb); |
542 | tunnel->recursion--; | |
543 | return 0; | |
544 | } | |
545 | if (skb->sk) | |
546 | skb_set_owner_w(new_skb, skb->sk); | |
547 | dev_kfree_skb(skb); | |
548 | skb = new_skb; | |
0660e03f | 549 | iph6 = ipv6_hdr(skb); |
1da177e4 LT |
550 | } |
551 | ||
b0e380b1 | 552 | skb->transport_header = skb->network_header; |
e2d1bca7 ACM |
553 | skb_push(skb, sizeof(struct iphdr)); |
554 | skb_reset_network_header(skb); | |
1da177e4 | 555 | memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt)); |
8cdfab8a | 556 | IPCB(skb)->flags = 0; |
1da177e4 LT |
557 | dst_release(skb->dst); |
558 | skb->dst = &rt->u.dst; | |
559 | ||
560 | /* | |
561 | * Push down and install the IPIP header. | |
562 | */ | |
563 | ||
eddc9ec5 | 564 | iph = ip_hdr(skb); |
1da177e4 LT |
565 | iph->version = 4; |
566 | iph->ihl = sizeof(struct iphdr)>>2; | |
567 | if (mtu > IPV6_MIN_MTU) | |
568 | iph->frag_off = htons(IP_DF); | |
569 | else | |
570 | iph->frag_off = 0; | |
571 | ||
572 | iph->protocol = IPPROTO_IPV6; | |
573 | iph->tos = INET_ECN_encapsulate(tos, ipv6_get_dsfield(iph6)); | |
574 | iph->daddr = rt->rt_dst; | |
575 | iph->saddr = rt->rt_src; | |
576 | ||
577 | if ((iph->ttl = tiph->ttl) == 0) | |
578 | iph->ttl = iph6->hop_limit; | |
579 | ||
580 | nf_reset(skb); | |
581 | ||
582 | IPTUNNEL_XMIT(); | |
583 | tunnel->recursion--; | |
584 | return 0; | |
585 | ||
586 | tx_error_icmp: | |
587 | dst_link_failure(skb); | |
588 | tx_error: | |
589 | stats->tx_errors++; | |
590 | dev_kfree_skb(skb); | |
591 | tunnel->recursion--; | |
592 | return 0; | |
593 | } | |
594 | ||
595 | static int | |
596 | ipip6_tunnel_ioctl (struct net_device *dev, struct ifreq *ifr, int cmd) | |
597 | { | |
598 | int err = 0; | |
599 | struct ip_tunnel_parm p; | |
600 | struct ip_tunnel *t; | |
601 | ||
602 | switch (cmd) { | |
603 | case SIOCGETTUNNEL: | |
604 | t = NULL; | |
605 | if (dev == ipip6_fb_tunnel_dev) { | |
606 | if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) { | |
607 | err = -EFAULT; | |
608 | break; | |
609 | } | |
610 | t = ipip6_tunnel_locate(&p, 0); | |
611 | } | |
612 | if (t == NULL) | |
2941a486 | 613 | t = netdev_priv(dev); |
1da177e4 LT |
614 | memcpy(&p, &t->parms, sizeof(p)); |
615 | if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p))) | |
616 | err = -EFAULT; | |
617 | break; | |
618 | ||
619 | case SIOCADDTUNNEL: | |
620 | case SIOCCHGTUNNEL: | |
621 | err = -EPERM; | |
622 | if (!capable(CAP_NET_ADMIN)) | |
623 | goto done; | |
624 | ||
625 | err = -EFAULT; | |
626 | if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) | |
627 | goto done; | |
628 | ||
629 | err = -EINVAL; | |
630 | if (p.iph.version != 4 || p.iph.protocol != IPPROTO_IPV6 || | |
631 | p.iph.ihl != 5 || (p.iph.frag_off&htons(~IP_DF))) | |
632 | goto done; | |
633 | if (p.iph.ttl) | |
634 | p.iph.frag_off |= htons(IP_DF); | |
635 | ||
636 | t = ipip6_tunnel_locate(&p, cmd == SIOCADDTUNNEL); | |
637 | ||
638 | if (dev != ipip6_fb_tunnel_dev && cmd == SIOCCHGTUNNEL) { | |
639 | if (t != NULL) { | |
640 | if (t->dev != dev) { | |
641 | err = -EEXIST; | |
642 | break; | |
643 | } | |
644 | } else { | |
645 | if (((dev->flags&IFF_POINTOPOINT) && !p.iph.daddr) || | |
646 | (!(dev->flags&IFF_POINTOPOINT) && p.iph.daddr)) { | |
647 | err = -EINVAL; | |
648 | break; | |
649 | } | |
2941a486 | 650 | t = netdev_priv(dev); |
1da177e4 LT |
651 | ipip6_tunnel_unlink(t); |
652 | t->parms.iph.saddr = p.iph.saddr; | |
653 | t->parms.iph.daddr = p.iph.daddr; | |
654 | memcpy(dev->dev_addr, &p.iph.saddr, 4); | |
655 | memcpy(dev->broadcast, &p.iph.daddr, 4); | |
656 | ipip6_tunnel_link(t); | |
657 | netdev_state_change(dev); | |
658 | } | |
659 | } | |
660 | ||
661 | if (t) { | |
662 | err = 0; | |
663 | if (cmd == SIOCCHGTUNNEL) { | |
664 | t->parms.iph.ttl = p.iph.ttl; | |
665 | t->parms.iph.tos = p.iph.tos; | |
666 | } | |
667 | if (copy_to_user(ifr->ifr_ifru.ifru_data, &t->parms, sizeof(p))) | |
668 | err = -EFAULT; | |
669 | } else | |
670 | err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT); | |
671 | break; | |
672 | ||
673 | case SIOCDELTUNNEL: | |
674 | err = -EPERM; | |
675 | if (!capable(CAP_NET_ADMIN)) | |
676 | goto done; | |
677 | ||
678 | if (dev == ipip6_fb_tunnel_dev) { | |
679 | err = -EFAULT; | |
680 | if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) | |
681 | goto done; | |
682 | err = -ENOENT; | |
683 | if ((t = ipip6_tunnel_locate(&p, 0)) == NULL) | |
684 | goto done; | |
685 | err = -EPERM; | |
2941a486 | 686 | if (t == netdev_priv(ipip6_fb_tunnel_dev)) |
1da177e4 LT |
687 | goto done; |
688 | dev = t->dev; | |
689 | } | |
22f8cde5 SH |
690 | unregister_netdevice(dev); |
691 | err = 0; | |
1da177e4 LT |
692 | break; |
693 | ||
694 | default: | |
695 | err = -EINVAL; | |
696 | } | |
697 | ||
698 | done: | |
699 | return err; | |
700 | } | |
701 | ||
702 | static struct net_device_stats *ipip6_tunnel_get_stats(struct net_device *dev) | |
703 | { | |
2941a486 | 704 | return &(((struct ip_tunnel*)netdev_priv(dev))->stat); |
1da177e4 LT |
705 | } |
706 | ||
707 | static int ipip6_tunnel_change_mtu(struct net_device *dev, int new_mtu) | |
708 | { | |
709 | if (new_mtu < IPV6_MIN_MTU || new_mtu > 0xFFF8 - sizeof(struct iphdr)) | |
710 | return -EINVAL; | |
711 | dev->mtu = new_mtu; | |
712 | return 0; | |
713 | } | |
714 | ||
715 | static void ipip6_tunnel_setup(struct net_device *dev) | |
716 | { | |
1da177e4 LT |
717 | dev->uninit = ipip6_tunnel_uninit; |
718 | dev->destructor = free_netdev; | |
719 | dev->hard_start_xmit = ipip6_tunnel_xmit; | |
720 | dev->get_stats = ipip6_tunnel_get_stats; | |
721 | dev->do_ioctl = ipip6_tunnel_ioctl; | |
722 | dev->change_mtu = ipip6_tunnel_change_mtu; | |
723 | ||
724 | dev->type = ARPHRD_SIT; | |
725 | dev->hard_header_len = LL_MAX_HEADER + sizeof(struct iphdr); | |
46f25dff | 726 | dev->mtu = ETH_DATA_LEN - sizeof(struct iphdr); |
1da177e4 LT |
727 | dev->flags = IFF_NOARP; |
728 | dev->iflink = 0; | |
729 | dev->addr_len = 4; | |
730 | } | |
731 | ||
732 | static int ipip6_tunnel_init(struct net_device *dev) | |
733 | { | |
734 | struct net_device *tdev = NULL; | |
735 | struct ip_tunnel *tunnel; | |
736 | struct iphdr *iph; | |
737 | ||
2941a486 | 738 | tunnel = netdev_priv(dev); |
1da177e4 LT |
739 | iph = &tunnel->parms.iph; |
740 | ||
741 | tunnel->dev = dev; | |
742 | strcpy(tunnel->parms.name, dev->name); | |
743 | ||
744 | memcpy(dev->dev_addr, &tunnel->parms.iph.saddr, 4); | |
745 | memcpy(dev->broadcast, &tunnel->parms.iph.daddr, 4); | |
746 | ||
747 | if (iph->daddr) { | |
748 | struct flowi fl = { .nl_u = { .ip4_u = | |
749 | { .daddr = iph->daddr, | |
750 | .saddr = iph->saddr, | |
751 | .tos = RT_TOS(iph->tos) } }, | |
752 | .oif = tunnel->parms.link, | |
753 | .proto = IPPROTO_IPV6 }; | |
754 | struct rtable *rt; | |
755 | if (!ip_route_output_key(&rt, &fl)) { | |
756 | tdev = rt->u.dst.dev; | |
757 | ip_rt_put(rt); | |
758 | } | |
759 | dev->flags |= IFF_POINTOPOINT; | |
760 | } | |
761 | ||
762 | if (!tdev && tunnel->parms.link) | |
881d966b | 763 | tdev = __dev_get_by_index(&init_net, tunnel->parms.link); |
1da177e4 LT |
764 | |
765 | if (tdev) { | |
766 | dev->hard_header_len = tdev->hard_header_len + sizeof(struct iphdr); | |
767 | dev->mtu = tdev->mtu - sizeof(struct iphdr); | |
768 | if (dev->mtu < IPV6_MIN_MTU) | |
769 | dev->mtu = IPV6_MIN_MTU; | |
770 | } | |
771 | dev->iflink = tunnel->parms.link; | |
772 | ||
773 | return 0; | |
774 | } | |
775 | ||
20380731 | 776 | static int __init ipip6_fb_tunnel_init(struct net_device *dev) |
1da177e4 | 777 | { |
2941a486 | 778 | struct ip_tunnel *tunnel = netdev_priv(dev); |
1da177e4 LT |
779 | struct iphdr *iph = &tunnel->parms.iph; |
780 | ||
781 | tunnel->dev = dev; | |
782 | strcpy(tunnel->parms.name, dev->name); | |
783 | ||
784 | iph->version = 4; | |
785 | iph->protocol = IPPROTO_IPV6; | |
786 | iph->ihl = 5; | |
787 | iph->ttl = 64; | |
788 | ||
789 | dev_hold(dev); | |
790 | tunnels_wc[0] = tunnel; | |
791 | return 0; | |
792 | } | |
793 | ||
c73cb5a2 | 794 | static struct xfrm_tunnel sit_handler = { |
1da177e4 LT |
795 | .handler = ipip6_rcv, |
796 | .err_handler = ipip6_err, | |
c73cb5a2 | 797 | .priority = 1, |
1da177e4 LT |
798 | }; |
799 | ||
db44575f AK |
800 | static void __exit sit_destroy_tunnels(void) |
801 | { | |
802 | int prio; | |
803 | ||
804 | for (prio = 1; prio < 4; prio++) { | |
805 | int h; | |
806 | for (h = 0; h < HASH_SIZE; h++) { | |
807 | struct ip_tunnel *t; | |
808 | while ((t = tunnels[prio][h]) != NULL) | |
809 | unregister_netdevice(t->dev); | |
810 | } | |
811 | } | |
812 | } | |
813 | ||
89c89458 | 814 | static void __exit sit_cleanup(void) |
1da177e4 | 815 | { |
c73cb5a2 | 816 | xfrm4_tunnel_deregister(&sit_handler, AF_INET6); |
db44575f AK |
817 | |
818 | rtnl_lock(); | |
819 | sit_destroy_tunnels(); | |
820 | unregister_netdevice(ipip6_fb_tunnel_dev); | |
821 | rtnl_unlock(); | |
1da177e4 LT |
822 | } |
823 | ||
89c89458 | 824 | static int __init sit_init(void) |
1da177e4 LT |
825 | { |
826 | int err; | |
827 | ||
828 | printk(KERN_INFO "IPv6 over IPv4 tunneling driver\n"); | |
829 | ||
c73cb5a2 | 830 | if (xfrm4_tunnel_register(&sit_handler, AF_INET6) < 0) { |
1da177e4 LT |
831 | printk(KERN_INFO "sit init: Can't add protocol\n"); |
832 | return -EAGAIN; | |
833 | } | |
834 | ||
1ab1457c | 835 | ipip6_fb_tunnel_dev = alloc_netdev(sizeof(struct ip_tunnel), "sit0", |
1da177e4 LT |
836 | ipip6_tunnel_setup); |
837 | if (!ipip6_fb_tunnel_dev) { | |
838 | err = -ENOMEM; | |
839 | goto err1; | |
840 | } | |
841 | ||
842 | ipip6_fb_tunnel_dev->init = ipip6_fb_tunnel_init; | |
843 | ||
844 | if ((err = register_netdev(ipip6_fb_tunnel_dev))) | |
845 | goto err2; | |
846 | ||
847 | out: | |
848 | return err; | |
849 | err2: | |
850 | free_netdev(ipip6_fb_tunnel_dev); | |
851 | err1: | |
c73cb5a2 | 852 | xfrm4_tunnel_deregister(&sit_handler, AF_INET6); |
1da177e4 LT |
853 | goto out; |
854 | } | |
989e5b96 JR |
855 | |
856 | module_init(sit_init); | |
857 | module_exit(sit_cleanup); | |
39c85086 | 858 | MODULE_LICENSE("GPL"); |
daccff02 | 859 | MODULE_ALIAS("sit0"); |