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 | |
c7dc89c0 | 19 | * Fred L. Templin <fltemplin@acm.org>: isatap support |
1da177e4 LT |
20 | */ |
21 | ||
1da177e4 | 22 | #include <linux/module.h> |
4fc268d2 | 23 | #include <linux/capability.h> |
1da177e4 LT |
24 | #include <linux/errno.h> |
25 | #include <linux/types.h> | |
26 | #include <linux/socket.h> | |
27 | #include <linux/sockios.h> | |
1da177e4 LT |
28 | #include <linux/net.h> |
29 | #include <linux/in6.h> | |
30 | #include <linux/netdevice.h> | |
31 | #include <linux/if_arp.h> | |
32 | #include <linux/icmp.h> | |
33 | #include <asm/uaccess.h> | |
34 | #include <linux/init.h> | |
35 | #include <linux/netfilter_ipv4.h> | |
46f25dff | 36 | #include <linux/if_ether.h> |
1da177e4 LT |
37 | |
38 | #include <net/sock.h> | |
39 | #include <net/snmp.h> | |
40 | ||
41 | #include <net/ipv6.h> | |
42 | #include <net/protocol.h> | |
43 | #include <net/transp_v6.h> | |
44 | #include <net/ip6_fib.h> | |
45 | #include <net/ip6_route.h> | |
46 | #include <net/ndisc.h> | |
47 | #include <net/addrconf.h> | |
48 | #include <net/ip.h> | |
49 | #include <net/udp.h> | |
50 | #include <net/icmp.h> | |
51 | #include <net/ipip.h> | |
52 | #include <net/inet_ecn.h> | |
53 | #include <net/xfrm.h> | |
54 | #include <net/dsfield.h> | |
55 | ||
56 | /* | |
57 | This version of net/ipv6/sit.c is cloned of net/ipv4/ip_gre.c | |
58 | ||
59 | For comments look at net/ipv4/ip_gre.c --ANK | |
60 | */ | |
61 | ||
62 | #define HASH_SIZE 16 | |
e69a4adc | 63 | #define HASH(addr) (((__force u32)addr^((__force u32)addr>>4))&0xF) |
1da177e4 LT |
64 | |
65 | static int ipip6_fb_tunnel_init(struct net_device *dev); | |
66 | static int ipip6_tunnel_init(struct net_device *dev); | |
67 | static void ipip6_tunnel_setup(struct net_device *dev); | |
68 | ||
69 | static struct net_device *ipip6_fb_tunnel_dev; | |
70 | ||
71 | static struct ip_tunnel *tunnels_r_l[HASH_SIZE]; | |
72 | static struct ip_tunnel *tunnels_r[HASH_SIZE]; | |
73 | static struct ip_tunnel *tunnels_l[HASH_SIZE]; | |
74 | static struct ip_tunnel *tunnels_wc[1]; | |
75 | static struct ip_tunnel **tunnels[4] = { tunnels_wc, tunnels_l, tunnels_r, tunnels_r_l }; | |
76 | ||
77 | static DEFINE_RWLOCK(ipip6_lock); | |
78 | ||
e69a4adc | 79 | static struct ip_tunnel * ipip6_tunnel_lookup(__be32 remote, __be32 local) |
1da177e4 LT |
80 | { |
81 | unsigned h0 = HASH(remote); | |
82 | unsigned h1 = HASH(local); | |
83 | struct ip_tunnel *t; | |
84 | ||
85 | for (t = tunnels_r_l[h0^h1]; t; t = t->next) { | |
86 | if (local == t->parms.iph.saddr && | |
87 | remote == t->parms.iph.daddr && (t->dev->flags&IFF_UP)) | |
88 | return t; | |
89 | } | |
90 | for (t = tunnels_r[h0]; t; t = t->next) { | |
91 | if (remote == t->parms.iph.daddr && (t->dev->flags&IFF_UP)) | |
92 | return t; | |
93 | } | |
94 | for (t = tunnels_l[h1]; t; t = t->next) { | |
95 | if (local == t->parms.iph.saddr && (t->dev->flags&IFF_UP)) | |
96 | return t; | |
97 | } | |
98 | if ((t = tunnels_wc[0]) != NULL && (t->dev->flags&IFF_UP)) | |
99 | return t; | |
100 | return NULL; | |
101 | } | |
102 | ||
420fe234 | 103 | static struct ip_tunnel **__ipip6_bucket(struct ip_tunnel_parm *parms) |
1da177e4 | 104 | { |
420fe234 YH |
105 | __be32 remote = parms->iph.daddr; |
106 | __be32 local = parms->iph.saddr; | |
1da177e4 LT |
107 | unsigned h = 0; |
108 | int prio = 0; | |
109 | ||
110 | if (remote) { | |
111 | prio |= 2; | |
112 | h ^= HASH(remote); | |
113 | } | |
114 | if (local) { | |
115 | prio |= 1; | |
116 | h ^= HASH(local); | |
117 | } | |
118 | return &tunnels[prio][h]; | |
119 | } | |
120 | ||
420fe234 YH |
121 | static inline struct ip_tunnel **ipip6_bucket(struct ip_tunnel *t) |
122 | { | |
123 | return __ipip6_bucket(&t->parms); | |
124 | } | |
125 | ||
1da177e4 LT |
126 | static void ipip6_tunnel_unlink(struct ip_tunnel *t) |
127 | { | |
128 | struct ip_tunnel **tp; | |
129 | ||
130 | for (tp = ipip6_bucket(t); *tp; tp = &(*tp)->next) { | |
131 | if (t == *tp) { | |
132 | write_lock_bh(&ipip6_lock); | |
133 | *tp = t->next; | |
134 | write_unlock_bh(&ipip6_lock); | |
135 | break; | |
136 | } | |
137 | } | |
138 | } | |
139 | ||
140 | static void ipip6_tunnel_link(struct ip_tunnel *t) | |
141 | { | |
142 | struct ip_tunnel **tp = ipip6_bucket(t); | |
143 | ||
144 | t->next = *tp; | |
145 | write_lock_bh(&ipip6_lock); | |
146 | *tp = t; | |
147 | write_unlock_bh(&ipip6_lock); | |
148 | } | |
149 | ||
150 | static struct ip_tunnel * ipip6_tunnel_locate(struct ip_tunnel_parm *parms, int create) | |
151 | { | |
e69a4adc AV |
152 | __be32 remote = parms->iph.daddr; |
153 | __be32 local = parms->iph.saddr; | |
1da177e4 LT |
154 | struct ip_tunnel *t, **tp, *nt; |
155 | struct net_device *dev; | |
1da177e4 LT |
156 | char name[IFNAMSIZ]; |
157 | ||
420fe234 | 158 | for (tp = __ipip6_bucket(parms); (t = *tp) != NULL; tp = &t->next) { |
1da177e4 LT |
159 | if (local == t->parms.iph.saddr && remote == t->parms.iph.daddr) |
160 | return t; | |
161 | } | |
162 | if (!create) | |
163 | goto failed; | |
164 | ||
165 | if (parms->name[0]) | |
166 | strlcpy(name, parms->name, IFNAMSIZ); | |
34cc7ba6 PE |
167 | else |
168 | sprintf(name, "sit%%d"); | |
1da177e4 LT |
169 | |
170 | dev = alloc_netdev(sizeof(*t), name, ipip6_tunnel_setup); | |
171 | if (dev == NULL) | |
172 | return NULL; | |
173 | ||
b37d428b PE |
174 | if (strchr(name, '%')) { |
175 | if (dev_alloc_name(dev, name) < 0) | |
176 | goto failed_free; | |
177 | } | |
178 | ||
2941a486 | 179 | nt = netdev_priv(dev); |
1da177e4 LT |
180 | dev->init = ipip6_tunnel_init; |
181 | nt->parms = *parms; | |
182 | ||
c7dc89c0 FT |
183 | if (parms->i_flags & SIT_ISATAP) |
184 | dev->priv_flags |= IFF_ISATAP; | |
185 | ||
b37d428b PE |
186 | if (register_netdevice(dev) < 0) |
187 | goto failed_free; | |
1da177e4 LT |
188 | |
189 | dev_hold(dev); | |
190 | ||
191 | ipip6_tunnel_link(nt); | |
1da177e4 LT |
192 | return nt; |
193 | ||
b37d428b PE |
194 | failed_free: |
195 | free_netdev(dev); | |
1da177e4 LT |
196 | failed: |
197 | return NULL; | |
198 | } | |
199 | ||
200 | static void ipip6_tunnel_uninit(struct net_device *dev) | |
201 | { | |
202 | if (dev == ipip6_fb_tunnel_dev) { | |
203 | write_lock_bh(&ipip6_lock); | |
204 | tunnels_wc[0] = NULL; | |
205 | write_unlock_bh(&ipip6_lock); | |
206 | dev_put(dev); | |
207 | } else { | |
2941a486 | 208 | ipip6_tunnel_unlink(netdev_priv(dev)); |
1da177e4 LT |
209 | dev_put(dev); |
210 | } | |
211 | } | |
212 | ||
213 | ||
c73cb5a2 | 214 | static int ipip6_err(struct sk_buff *skb, u32 info) |
1da177e4 LT |
215 | { |
216 | #ifndef I_WISH_WORLD_WERE_PERFECT | |
217 | ||
218 | /* It is not :-( All the routers (except for Linux) return only | |
219 | 8 bytes of packet payload. It means, that precise relaying of | |
220 | ICMP in the real Internet is absolutely infeasible. | |
221 | */ | |
222 | struct iphdr *iph = (struct iphdr*)skb->data; | |
88c7664f ACM |
223 | const int type = icmp_hdr(skb)->type; |
224 | const int code = icmp_hdr(skb)->code; | |
1da177e4 | 225 | struct ip_tunnel *t; |
c73cb5a2 | 226 | int err; |
1da177e4 LT |
227 | |
228 | switch (type) { | |
229 | default: | |
230 | case ICMP_PARAMETERPROB: | |
c73cb5a2 | 231 | return 0; |
1da177e4 LT |
232 | |
233 | case ICMP_DEST_UNREACH: | |
234 | switch (code) { | |
235 | case ICMP_SR_FAILED: | |
236 | case ICMP_PORT_UNREACH: | |
237 | /* Impossible event. */ | |
c73cb5a2 | 238 | return 0; |
1da177e4 LT |
239 | case ICMP_FRAG_NEEDED: |
240 | /* Soft state for pmtu is maintained by IP core. */ | |
c73cb5a2 | 241 | return 0; |
1da177e4 LT |
242 | default: |
243 | /* All others are translated to HOST_UNREACH. | |
244 | rfc2003 contains "deep thoughts" about NET_UNREACH, | |
245 | I believe they are just ether pollution. --ANK | |
246 | */ | |
247 | break; | |
248 | } | |
249 | break; | |
250 | case ICMP_TIME_EXCEEDED: | |
251 | if (code != ICMP_EXC_TTL) | |
c73cb5a2 | 252 | return 0; |
1da177e4 LT |
253 | break; |
254 | } | |
255 | ||
c73cb5a2 KM |
256 | err = -ENOENT; |
257 | ||
1da177e4 LT |
258 | read_lock(&ipip6_lock); |
259 | t = ipip6_tunnel_lookup(iph->daddr, iph->saddr); | |
260 | if (t == NULL || t->parms.iph.daddr == 0) | |
261 | goto out; | |
c73cb5a2 KM |
262 | |
263 | err = 0; | |
1da177e4 LT |
264 | if (t->parms.iph.ttl == 0 && type == ICMP_TIME_EXCEEDED) |
265 | goto out; | |
266 | ||
267 | if (jiffies - t->err_time < IPTUNNEL_ERR_TIMEO) | |
268 | t->err_count++; | |
269 | else | |
270 | t->err_count = 1; | |
271 | t->err_time = jiffies; | |
272 | out: | |
273 | read_unlock(&ipip6_lock); | |
c73cb5a2 | 274 | return err; |
1da177e4 LT |
275 | #else |
276 | struct iphdr *iph = (struct iphdr*)dp; | |
277 | int hlen = iph->ihl<<2; | |
278 | struct ipv6hdr *iph6; | |
88c7664f ACM |
279 | const int type = icmp_hdr(skb)->type; |
280 | const int code = icmp_hdr(skb)->code; | |
1da177e4 LT |
281 | int rel_type = 0; |
282 | int rel_code = 0; | |
283 | int rel_info = 0; | |
284 | struct sk_buff *skb2; | |
285 | struct rt6_info *rt6i; | |
286 | ||
287 | if (len < hlen + sizeof(struct ipv6hdr)) | |
288 | return; | |
289 | iph6 = (struct ipv6hdr*)(dp + hlen); | |
290 | ||
291 | switch (type) { | |
292 | default: | |
293 | return; | |
294 | case ICMP_PARAMETERPROB: | |
88c7664f | 295 | if (icmp_hdr(skb)->un.gateway < hlen) |
1da177e4 LT |
296 | return; |
297 | ||
298 | /* So... This guy found something strange INSIDE encapsulated | |
299 | packet. Well, he is fool, but what can we do ? | |
300 | */ | |
301 | rel_type = ICMPV6_PARAMPROB; | |
88c7664f | 302 | rel_info = icmp_hdr(skb)->un.gateway - hlen; |
1da177e4 LT |
303 | break; |
304 | ||
305 | case ICMP_DEST_UNREACH: | |
306 | switch (code) { | |
307 | case ICMP_SR_FAILED: | |
308 | case ICMP_PORT_UNREACH: | |
309 | /* Impossible event. */ | |
310 | return; | |
311 | case ICMP_FRAG_NEEDED: | |
312 | /* Too complicated case ... */ | |
313 | return; | |
314 | default: | |
315 | /* All others are translated to HOST_UNREACH. | |
316 | rfc2003 contains "deep thoughts" about NET_UNREACH, | |
317 | I believe, it is just ether pollution. --ANK | |
318 | */ | |
319 | rel_type = ICMPV6_DEST_UNREACH; | |
320 | rel_code = ICMPV6_ADDR_UNREACH; | |
321 | break; | |
322 | } | |
323 | break; | |
324 | case ICMP_TIME_EXCEEDED: | |
325 | if (code != ICMP_EXC_TTL) | |
326 | return; | |
327 | rel_type = ICMPV6_TIME_EXCEED; | |
328 | rel_code = ICMPV6_EXC_HOPLIMIT; | |
329 | break; | |
330 | } | |
331 | ||
332 | /* Prepare fake skb to feed it to icmpv6_send */ | |
333 | skb2 = skb_clone(skb, GFP_ATOMIC); | |
334 | if (skb2 == NULL) | |
c73cb5a2 | 335 | return 0; |
1da177e4 LT |
336 | dst_release(skb2->dst); |
337 | skb2->dst = NULL; | |
338 | skb_pull(skb2, skb->data - (u8*)iph6); | |
c1d2bbe1 | 339 | skb_reset_network_header(skb2); |
1da177e4 LT |
340 | |
341 | /* Try to guess incoming interface */ | |
342 | rt6i = rt6_lookup(&iph6->saddr, NULL, NULL, 0); | |
343 | if (rt6i && rt6i->rt6i_dev) { | |
344 | skb2->dev = rt6i->rt6i_dev; | |
345 | ||
346 | rt6i = rt6_lookup(&iph6->daddr, &iph6->saddr, NULL, 0); | |
347 | ||
348 | if (rt6i && rt6i->rt6i_dev && rt6i->rt6i_dev->type == ARPHRD_SIT) { | |
2941a486 | 349 | struct ip_tunnel *t = netdev_priv(rt6i->rt6i_dev); |
1da177e4 LT |
350 | if (rel_type == ICMPV6_TIME_EXCEED && t->parms.iph.ttl) { |
351 | rel_type = ICMPV6_DEST_UNREACH; | |
352 | rel_code = ICMPV6_ADDR_UNREACH; | |
353 | } | |
354 | icmpv6_send(skb2, rel_type, rel_code, rel_info, skb2->dev); | |
355 | } | |
356 | } | |
357 | kfree_skb(skb2); | |
c73cb5a2 | 358 | return 0; |
1da177e4 LT |
359 | #endif |
360 | } | |
361 | ||
362 | static inline void ipip6_ecn_decapsulate(struct iphdr *iph, struct sk_buff *skb) | |
363 | { | |
364 | if (INET_ECN_is_ce(iph->tos)) | |
0660e03f | 365 | IP6_ECN_set_ce(ipv6_hdr(skb)); |
1da177e4 LT |
366 | } |
367 | ||
c7dc89c0 FT |
368 | /* ISATAP (RFC4214) - check source address */ |
369 | static int | |
370 | isatap_srcok(struct sk_buff *skb, struct iphdr *iph, struct net_device *dev) | |
371 | { | |
372 | struct neighbour *neigh; | |
373 | struct dst_entry *dst; | |
374 | struct rt6_info *rt; | |
375 | struct flowi fl; | |
376 | struct in6_addr *addr6; | |
377 | struct in6_addr rtr; | |
378 | struct ipv6hdr *iph6; | |
379 | int ok = 0; | |
380 | ||
381 | /* from onlink default router */ | |
382 | ipv6_addr_set(&rtr, htonl(0xFE800000), 0, 0, 0); | |
383 | ipv6_isatap_eui64(rtr.s6_addr + 8, iph->saddr); | |
384 | if ((rt = rt6_get_dflt_router(&rtr, dev))) { | |
385 | dst_release(&rt->u.dst); | |
386 | return 1; | |
387 | } | |
388 | ||
389 | iph6 = ipv6_hdr(skb); | |
390 | memset(&fl, 0, sizeof(fl)); | |
391 | fl.proto = iph6->nexthdr; | |
392 | ipv6_addr_copy(&fl.fl6_dst, &iph6->saddr); | |
393 | fl.oif = dev->ifindex; | |
394 | security_skb_classify_flow(skb, &fl); | |
395 | ||
396 | dst = ip6_route_output(NULL, &fl); | |
397 | if (!dst->error && (dst->dev == dev) && (neigh = dst->neighbour)) { | |
398 | ||
399 | addr6 = (struct in6_addr*)&neigh->primary_key; | |
400 | ||
401 | /* from correct previous hop */ | |
402 | if (ipv6_addr_is_isatap(addr6) && | |
403 | (addr6->s6_addr32[3] == iph->saddr)) | |
404 | ok = 1; | |
405 | } | |
406 | dst_release(dst); | |
407 | return ok; | |
408 | } | |
409 | ||
1da177e4 LT |
410 | static int ipip6_rcv(struct sk_buff *skb) |
411 | { | |
412 | struct iphdr *iph; | |
413 | struct ip_tunnel *tunnel; | |
414 | ||
415 | if (!pskb_may_pull(skb, sizeof(struct ipv6hdr))) | |
416 | goto out; | |
417 | ||
eddc9ec5 | 418 | iph = ip_hdr(skb); |
1da177e4 LT |
419 | |
420 | read_lock(&ipip6_lock); | |
421 | if ((tunnel = ipip6_tunnel_lookup(iph->saddr, iph->daddr)) != NULL) { | |
422 | secpath_reset(skb); | |
b0e380b1 | 423 | skb->mac_header = skb->network_header; |
c1d2bbe1 | 424 | skb_reset_network_header(skb); |
8cdfab8a | 425 | IPCB(skb)->flags = 0; |
1da177e4 LT |
426 | skb->protocol = htons(ETH_P_IPV6); |
427 | skb->pkt_type = PACKET_HOST; | |
c7dc89c0 FT |
428 | |
429 | if ((tunnel->dev->priv_flags & IFF_ISATAP) && | |
430 | !isatap_srcok(skb, iph, tunnel->dev)) { | |
431 | tunnel->stat.rx_errors++; | |
432 | read_unlock(&ipip6_lock); | |
433 | kfree_skb(skb); | |
434 | return 0; | |
435 | } | |
1da177e4 LT |
436 | tunnel->stat.rx_packets++; |
437 | tunnel->stat.rx_bytes += skb->len; | |
438 | skb->dev = tunnel->dev; | |
439 | dst_release(skb->dst); | |
440 | skb->dst = NULL; | |
441 | nf_reset(skb); | |
442 | ipip6_ecn_decapsulate(iph, skb); | |
443 | netif_rx(skb); | |
444 | read_unlock(&ipip6_lock); | |
445 | return 0; | |
446 | } | |
447 | ||
45af08be | 448 | icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PORT_UNREACH, 0); |
1da177e4 LT |
449 | kfree_skb(skb); |
450 | read_unlock(&ipip6_lock); | |
451 | out: | |
452 | return 0; | |
453 | } | |
454 | ||
455 | /* Returns the embedded IPv4 address if the IPv6 address | |
456 | comes from 6to4 (RFC 3056) addr space */ | |
457 | ||
e69a4adc | 458 | static inline __be32 try_6to4(struct in6_addr *v6dst) |
1da177e4 | 459 | { |
e69a4adc | 460 | __be32 dst = 0; |
1da177e4 LT |
461 | |
462 | if (v6dst->s6_addr16[0] == htons(0x2002)) { | |
1ab1457c | 463 | /* 6to4 v6 addr has 16 bits prefix, 32 v4addr, 16 SLA, ... */ |
1da177e4 LT |
464 | memcpy(&dst, &v6dst->s6_addr16[1], 4); |
465 | } | |
466 | return dst; | |
467 | } | |
468 | ||
469 | /* | |
470 | * This function assumes it is being called from dev_queue_xmit() | |
471 | * and that skb is filled properly by that function. | |
472 | */ | |
473 | ||
474 | static int ipip6_tunnel_xmit(struct sk_buff *skb, struct net_device *dev) | |
475 | { | |
2941a486 | 476 | struct ip_tunnel *tunnel = netdev_priv(dev); |
1da177e4 LT |
477 | struct net_device_stats *stats = &tunnel->stat; |
478 | struct iphdr *tiph = &tunnel->parms.iph; | |
0660e03f | 479 | struct ipv6hdr *iph6 = ipv6_hdr(skb); |
1da177e4 LT |
480 | u8 tos = tunnel->parms.iph.tos; |
481 | struct rtable *rt; /* Route to the other host */ | |
482 | struct net_device *tdev; /* Device to other host */ | |
483 | struct iphdr *iph; /* Our new IP header */ | |
c2636b4d | 484 | unsigned int max_headroom; /* The extra header space needed */ |
e69a4adc | 485 | __be32 dst = tiph->daddr; |
1da177e4 | 486 | int mtu; |
1ab1457c | 487 | struct in6_addr *addr6; |
1da177e4 LT |
488 | int addr_type; |
489 | ||
490 | if (tunnel->recursion++) { | |
491 | tunnel->stat.collisions++; | |
492 | goto tx_error; | |
493 | } | |
494 | ||
495 | if (skb->protocol != htons(ETH_P_IPV6)) | |
496 | goto tx_error; | |
497 | ||
c7dc89c0 FT |
498 | /* ISATAP (RFC4214) - must come before 6to4 */ |
499 | if (dev->priv_flags & IFF_ISATAP) { | |
500 | struct neighbour *neigh = NULL; | |
501 | ||
502 | if (skb->dst) | |
503 | neigh = skb->dst->neighbour; | |
504 | ||
505 | if (neigh == NULL) { | |
506 | if (net_ratelimit()) | |
507 | printk(KERN_DEBUG "sit: nexthop == NULL\n"); | |
508 | goto tx_error; | |
509 | } | |
510 | ||
511 | addr6 = (struct in6_addr*)&neigh->primary_key; | |
512 | addr_type = ipv6_addr_type(addr6); | |
513 | ||
514 | if ((addr_type & IPV6_ADDR_UNICAST) && | |
515 | ipv6_addr_is_isatap(addr6)) | |
516 | dst = addr6->s6_addr32[3]; | |
517 | else | |
518 | goto tx_error; | |
519 | } | |
520 | ||
1da177e4 LT |
521 | if (!dst) |
522 | dst = try_6to4(&iph6->daddr); | |
523 | ||
524 | if (!dst) { | |
525 | struct neighbour *neigh = NULL; | |
526 | ||
527 | if (skb->dst) | |
528 | neigh = skb->dst->neighbour; | |
529 | ||
530 | if (neigh == NULL) { | |
531 | if (net_ratelimit()) | |
532 | printk(KERN_DEBUG "sit: nexthop == NULL\n"); | |
533 | goto tx_error; | |
534 | } | |
535 | ||
536 | addr6 = (struct in6_addr*)&neigh->primary_key; | |
537 | addr_type = ipv6_addr_type(addr6); | |
538 | ||
539 | if (addr_type == IPV6_ADDR_ANY) { | |
0660e03f | 540 | addr6 = &ipv6_hdr(skb)->daddr; |
1da177e4 LT |
541 | addr_type = ipv6_addr_type(addr6); |
542 | } | |
543 | ||
544 | if ((addr_type & IPV6_ADDR_COMPATv4) == 0) | |
545 | goto tx_error_icmp; | |
546 | ||
547 | dst = addr6->s6_addr32[3]; | |
548 | } | |
549 | ||
550 | { | |
551 | struct flowi fl = { .nl_u = { .ip4_u = | |
552 | { .daddr = dst, | |
553 | .saddr = tiph->saddr, | |
554 | .tos = RT_TOS(tos) } }, | |
555 | .oif = tunnel->parms.link, | |
556 | .proto = IPPROTO_IPV6 }; | |
f206351a | 557 | if (ip_route_output_key(&init_net, &rt, &fl)) { |
1da177e4 LT |
558 | tunnel->stat.tx_carrier_errors++; |
559 | goto tx_error_icmp; | |
560 | } | |
561 | } | |
562 | if (rt->rt_type != RTN_UNICAST) { | |
563 | ip_rt_put(rt); | |
564 | tunnel->stat.tx_carrier_errors++; | |
565 | goto tx_error_icmp; | |
566 | } | |
567 | tdev = rt->u.dst.dev; | |
568 | ||
569 | if (tdev == dev) { | |
570 | ip_rt_put(rt); | |
571 | tunnel->stat.collisions++; | |
572 | goto tx_error; | |
573 | } | |
574 | ||
575 | if (tiph->frag_off) | |
576 | mtu = dst_mtu(&rt->u.dst) - sizeof(struct iphdr); | |
577 | else | |
578 | mtu = skb->dst ? dst_mtu(skb->dst) : dev->mtu; | |
579 | ||
580 | if (mtu < 68) { | |
581 | tunnel->stat.collisions++; | |
582 | ip_rt_put(rt); | |
583 | goto tx_error; | |
584 | } | |
585 | if (mtu < IPV6_MIN_MTU) | |
586 | mtu = IPV6_MIN_MTU; | |
587 | if (tunnel->parms.iph.daddr && skb->dst) | |
588 | skb->dst->ops->update_pmtu(skb->dst, mtu); | |
589 | ||
590 | if (skb->len > mtu) { | |
591 | icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu, dev); | |
592 | ip_rt_put(rt); | |
593 | goto tx_error; | |
594 | } | |
595 | ||
596 | if (tunnel->err_count > 0) { | |
597 | if (jiffies - tunnel->err_time < IPTUNNEL_ERR_TIMEO) { | |
598 | tunnel->err_count--; | |
599 | dst_link_failure(skb); | |
600 | } else | |
601 | tunnel->err_count = 0; | |
602 | } | |
603 | ||
604 | /* | |
605 | * Okay, now see if we can stuff it in the buffer as-is. | |
606 | */ | |
607 | max_headroom = LL_RESERVED_SPACE(tdev)+sizeof(struct iphdr); | |
608 | ||
cfbba49d PM |
609 | if (skb_headroom(skb) < max_headroom || skb_shared(skb) || |
610 | (skb_cloned(skb) && !skb_clone_writable(skb, 0))) { | |
1da177e4 LT |
611 | struct sk_buff *new_skb = skb_realloc_headroom(skb, max_headroom); |
612 | if (!new_skb) { | |
613 | ip_rt_put(rt); | |
1ab1457c | 614 | stats->tx_dropped++; |
1da177e4 LT |
615 | dev_kfree_skb(skb); |
616 | tunnel->recursion--; | |
617 | return 0; | |
618 | } | |
619 | if (skb->sk) | |
620 | skb_set_owner_w(new_skb, skb->sk); | |
621 | dev_kfree_skb(skb); | |
622 | skb = new_skb; | |
0660e03f | 623 | iph6 = ipv6_hdr(skb); |
1da177e4 LT |
624 | } |
625 | ||
b0e380b1 | 626 | skb->transport_header = skb->network_header; |
e2d1bca7 ACM |
627 | skb_push(skb, sizeof(struct iphdr)); |
628 | skb_reset_network_header(skb); | |
1da177e4 | 629 | memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt)); |
8cdfab8a | 630 | IPCB(skb)->flags = 0; |
1da177e4 LT |
631 | dst_release(skb->dst); |
632 | skb->dst = &rt->u.dst; | |
633 | ||
634 | /* | |
635 | * Push down and install the IPIP header. | |
636 | */ | |
637 | ||
eddc9ec5 | 638 | iph = ip_hdr(skb); |
1da177e4 LT |
639 | iph->version = 4; |
640 | iph->ihl = sizeof(struct iphdr)>>2; | |
641 | if (mtu > IPV6_MIN_MTU) | |
642 | iph->frag_off = htons(IP_DF); | |
643 | else | |
644 | iph->frag_off = 0; | |
645 | ||
646 | iph->protocol = IPPROTO_IPV6; | |
647 | iph->tos = INET_ECN_encapsulate(tos, ipv6_get_dsfield(iph6)); | |
648 | iph->daddr = rt->rt_dst; | |
649 | iph->saddr = rt->rt_src; | |
650 | ||
651 | if ((iph->ttl = tiph->ttl) == 0) | |
652 | iph->ttl = iph6->hop_limit; | |
653 | ||
654 | nf_reset(skb); | |
655 | ||
656 | IPTUNNEL_XMIT(); | |
657 | tunnel->recursion--; | |
658 | return 0; | |
659 | ||
660 | tx_error_icmp: | |
661 | dst_link_failure(skb); | |
662 | tx_error: | |
663 | stats->tx_errors++; | |
664 | dev_kfree_skb(skb); | |
665 | tunnel->recursion--; | |
666 | return 0; | |
667 | } | |
668 | ||
8a4a50f9 MS |
669 | static void ipip6_tunnel_bind_dev(struct net_device *dev) |
670 | { | |
671 | struct net_device *tdev = NULL; | |
672 | struct ip_tunnel *tunnel; | |
673 | struct iphdr *iph; | |
674 | ||
675 | tunnel = netdev_priv(dev); | |
676 | iph = &tunnel->parms.iph; | |
677 | ||
678 | if (iph->daddr) { | |
679 | struct flowi fl = { .nl_u = { .ip4_u = | |
680 | { .daddr = iph->daddr, | |
681 | .saddr = iph->saddr, | |
682 | .tos = RT_TOS(iph->tos) } }, | |
683 | .oif = tunnel->parms.link, | |
684 | .proto = IPPROTO_IPV6 }; | |
685 | struct rtable *rt; | |
f206351a | 686 | if (!ip_route_output_key(&init_net, &rt, &fl)) { |
8a4a50f9 MS |
687 | tdev = rt->u.dst.dev; |
688 | ip_rt_put(rt); | |
689 | } | |
690 | dev->flags |= IFF_POINTOPOINT; | |
691 | } | |
692 | ||
693 | if (!tdev && tunnel->parms.link) | |
694 | tdev = __dev_get_by_index(&init_net, tunnel->parms.link); | |
695 | ||
696 | if (tdev) { | |
697 | dev->hard_header_len = tdev->hard_header_len + sizeof(struct iphdr); | |
698 | dev->mtu = tdev->mtu - sizeof(struct iphdr); | |
699 | if (dev->mtu < IPV6_MIN_MTU) | |
700 | dev->mtu = IPV6_MIN_MTU; | |
701 | } | |
702 | dev->iflink = tunnel->parms.link; | |
703 | } | |
704 | ||
1da177e4 LT |
705 | static int |
706 | ipip6_tunnel_ioctl (struct net_device *dev, struct ifreq *ifr, int cmd) | |
707 | { | |
708 | int err = 0; | |
709 | struct ip_tunnel_parm p; | |
710 | struct ip_tunnel *t; | |
711 | ||
712 | switch (cmd) { | |
713 | case SIOCGETTUNNEL: | |
714 | t = NULL; | |
715 | if (dev == ipip6_fb_tunnel_dev) { | |
716 | if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) { | |
717 | err = -EFAULT; | |
718 | break; | |
719 | } | |
720 | t = ipip6_tunnel_locate(&p, 0); | |
721 | } | |
722 | if (t == NULL) | |
2941a486 | 723 | t = netdev_priv(dev); |
1da177e4 LT |
724 | memcpy(&p, &t->parms, sizeof(p)); |
725 | if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p))) | |
726 | err = -EFAULT; | |
727 | break; | |
728 | ||
729 | case SIOCADDTUNNEL: | |
730 | case SIOCCHGTUNNEL: | |
731 | err = -EPERM; | |
732 | if (!capable(CAP_NET_ADMIN)) | |
733 | goto done; | |
734 | ||
735 | err = -EFAULT; | |
736 | if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) | |
737 | goto done; | |
738 | ||
739 | err = -EINVAL; | |
740 | if (p.iph.version != 4 || p.iph.protocol != IPPROTO_IPV6 || | |
741 | p.iph.ihl != 5 || (p.iph.frag_off&htons(~IP_DF))) | |
742 | goto done; | |
743 | if (p.iph.ttl) | |
744 | p.iph.frag_off |= htons(IP_DF); | |
745 | ||
746 | t = ipip6_tunnel_locate(&p, cmd == SIOCADDTUNNEL); | |
747 | ||
748 | if (dev != ipip6_fb_tunnel_dev && cmd == SIOCCHGTUNNEL) { | |
749 | if (t != NULL) { | |
750 | if (t->dev != dev) { | |
751 | err = -EEXIST; | |
752 | break; | |
753 | } | |
754 | } else { | |
755 | if (((dev->flags&IFF_POINTOPOINT) && !p.iph.daddr) || | |
756 | (!(dev->flags&IFF_POINTOPOINT) && p.iph.daddr)) { | |
757 | err = -EINVAL; | |
758 | break; | |
759 | } | |
2941a486 | 760 | t = netdev_priv(dev); |
1da177e4 LT |
761 | ipip6_tunnel_unlink(t); |
762 | t->parms.iph.saddr = p.iph.saddr; | |
763 | t->parms.iph.daddr = p.iph.daddr; | |
764 | memcpy(dev->dev_addr, &p.iph.saddr, 4); | |
765 | memcpy(dev->broadcast, &p.iph.daddr, 4); | |
766 | ipip6_tunnel_link(t); | |
767 | netdev_state_change(dev); | |
768 | } | |
769 | } | |
770 | ||
771 | if (t) { | |
772 | err = 0; | |
773 | if (cmd == SIOCCHGTUNNEL) { | |
774 | t->parms.iph.ttl = p.iph.ttl; | |
775 | t->parms.iph.tos = p.iph.tos; | |
8a4a50f9 MS |
776 | if (t->parms.link != p.link) { |
777 | t->parms.link = p.link; | |
778 | ipip6_tunnel_bind_dev(dev); | |
779 | netdev_state_change(dev); | |
780 | } | |
1da177e4 LT |
781 | } |
782 | if (copy_to_user(ifr->ifr_ifru.ifru_data, &t->parms, sizeof(p))) | |
783 | err = -EFAULT; | |
784 | } else | |
785 | err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT); | |
786 | break; | |
787 | ||
788 | case SIOCDELTUNNEL: | |
789 | err = -EPERM; | |
790 | if (!capable(CAP_NET_ADMIN)) | |
791 | goto done; | |
792 | ||
793 | if (dev == ipip6_fb_tunnel_dev) { | |
794 | err = -EFAULT; | |
795 | if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) | |
796 | goto done; | |
797 | err = -ENOENT; | |
798 | if ((t = ipip6_tunnel_locate(&p, 0)) == NULL) | |
799 | goto done; | |
800 | err = -EPERM; | |
2941a486 | 801 | if (t == netdev_priv(ipip6_fb_tunnel_dev)) |
1da177e4 LT |
802 | goto done; |
803 | dev = t->dev; | |
804 | } | |
22f8cde5 SH |
805 | unregister_netdevice(dev); |
806 | err = 0; | |
1da177e4 LT |
807 | break; |
808 | ||
809 | default: | |
810 | err = -EINVAL; | |
811 | } | |
812 | ||
813 | done: | |
814 | return err; | |
815 | } | |
816 | ||
817 | static struct net_device_stats *ipip6_tunnel_get_stats(struct net_device *dev) | |
818 | { | |
2941a486 | 819 | return &(((struct ip_tunnel*)netdev_priv(dev))->stat); |
1da177e4 LT |
820 | } |
821 | ||
822 | static int ipip6_tunnel_change_mtu(struct net_device *dev, int new_mtu) | |
823 | { | |
824 | if (new_mtu < IPV6_MIN_MTU || new_mtu > 0xFFF8 - sizeof(struct iphdr)) | |
825 | return -EINVAL; | |
826 | dev->mtu = new_mtu; | |
827 | return 0; | |
828 | } | |
829 | ||
830 | static void ipip6_tunnel_setup(struct net_device *dev) | |
831 | { | |
1da177e4 LT |
832 | dev->uninit = ipip6_tunnel_uninit; |
833 | dev->destructor = free_netdev; | |
834 | dev->hard_start_xmit = ipip6_tunnel_xmit; | |
835 | dev->get_stats = ipip6_tunnel_get_stats; | |
836 | dev->do_ioctl = ipip6_tunnel_ioctl; | |
837 | dev->change_mtu = ipip6_tunnel_change_mtu; | |
838 | ||
839 | dev->type = ARPHRD_SIT; | |
840 | dev->hard_header_len = LL_MAX_HEADER + sizeof(struct iphdr); | |
46f25dff | 841 | dev->mtu = ETH_DATA_LEN - sizeof(struct iphdr); |
1da177e4 LT |
842 | dev->flags = IFF_NOARP; |
843 | dev->iflink = 0; | |
844 | dev->addr_len = 4; | |
845 | } | |
846 | ||
847 | static int ipip6_tunnel_init(struct net_device *dev) | |
848 | { | |
1da177e4 | 849 | struct ip_tunnel *tunnel; |
1da177e4 | 850 | |
2941a486 | 851 | tunnel = netdev_priv(dev); |
1da177e4 LT |
852 | |
853 | tunnel->dev = dev; | |
854 | strcpy(tunnel->parms.name, dev->name); | |
855 | ||
856 | memcpy(dev->dev_addr, &tunnel->parms.iph.saddr, 4); | |
857 | memcpy(dev->broadcast, &tunnel->parms.iph.daddr, 4); | |
858 | ||
8a4a50f9 | 859 | ipip6_tunnel_bind_dev(dev); |
1da177e4 LT |
860 | |
861 | return 0; | |
862 | } | |
863 | ||
20380731 | 864 | static int __init ipip6_fb_tunnel_init(struct net_device *dev) |
1da177e4 | 865 | { |
2941a486 | 866 | struct ip_tunnel *tunnel = netdev_priv(dev); |
1da177e4 LT |
867 | struct iphdr *iph = &tunnel->parms.iph; |
868 | ||
869 | tunnel->dev = dev; | |
870 | strcpy(tunnel->parms.name, dev->name); | |
871 | ||
872 | iph->version = 4; | |
873 | iph->protocol = IPPROTO_IPV6; | |
874 | iph->ihl = 5; | |
875 | iph->ttl = 64; | |
876 | ||
877 | dev_hold(dev); | |
878 | tunnels_wc[0] = tunnel; | |
879 | return 0; | |
880 | } | |
881 | ||
c73cb5a2 | 882 | static struct xfrm_tunnel sit_handler = { |
1da177e4 LT |
883 | .handler = ipip6_rcv, |
884 | .err_handler = ipip6_err, | |
c73cb5a2 | 885 | .priority = 1, |
1da177e4 LT |
886 | }; |
887 | ||
db44575f AK |
888 | static void __exit sit_destroy_tunnels(void) |
889 | { | |
890 | int prio; | |
891 | ||
892 | for (prio = 1; prio < 4; prio++) { | |
893 | int h; | |
894 | for (h = 0; h < HASH_SIZE; h++) { | |
895 | struct ip_tunnel *t; | |
896 | while ((t = tunnels[prio][h]) != NULL) | |
897 | unregister_netdevice(t->dev); | |
898 | } | |
899 | } | |
900 | } | |
901 | ||
89c89458 | 902 | static void __exit sit_cleanup(void) |
1da177e4 | 903 | { |
c73cb5a2 | 904 | xfrm4_tunnel_deregister(&sit_handler, AF_INET6); |
db44575f AK |
905 | |
906 | rtnl_lock(); | |
907 | sit_destroy_tunnels(); | |
908 | unregister_netdevice(ipip6_fb_tunnel_dev); | |
909 | rtnl_unlock(); | |
1da177e4 LT |
910 | } |
911 | ||
89c89458 | 912 | static int __init sit_init(void) |
1da177e4 LT |
913 | { |
914 | int err; | |
915 | ||
916 | printk(KERN_INFO "IPv6 over IPv4 tunneling driver\n"); | |
917 | ||
c73cb5a2 | 918 | if (xfrm4_tunnel_register(&sit_handler, AF_INET6) < 0) { |
1da177e4 LT |
919 | printk(KERN_INFO "sit init: Can't add protocol\n"); |
920 | return -EAGAIN; | |
921 | } | |
922 | ||
1ab1457c | 923 | ipip6_fb_tunnel_dev = alloc_netdev(sizeof(struct ip_tunnel), "sit0", |
1da177e4 LT |
924 | ipip6_tunnel_setup); |
925 | if (!ipip6_fb_tunnel_dev) { | |
926 | err = -ENOMEM; | |
927 | goto err1; | |
928 | } | |
929 | ||
930 | ipip6_fb_tunnel_dev->init = ipip6_fb_tunnel_init; | |
931 | ||
932 | if ((err = register_netdev(ipip6_fb_tunnel_dev))) | |
933 | goto err2; | |
934 | ||
935 | out: | |
936 | return err; | |
937 | err2: | |
938 | free_netdev(ipip6_fb_tunnel_dev); | |
939 | err1: | |
c73cb5a2 | 940 | xfrm4_tunnel_deregister(&sit_handler, AF_INET6); |
1da177e4 LT |
941 | goto out; |
942 | } | |
989e5b96 JR |
943 | |
944 | module_init(sit_init); | |
945 | module_exit(sit_cleanup); | |
39c85086 | 946 | MODULE_LICENSE("GPL"); |
daccff02 | 947 | MODULE_ALIAS("sit0"); |