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[IPV6] SIT: Add PRL management for ISATAP.
[net-next-2.6.git] / net / ipv6 / sit.c
CommitLineData
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
fadf6bf0 19 * Fred Templin <fred.l.templin@boeing.com>: 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
65static int ipip6_fb_tunnel_init(struct net_device *dev);
66static int ipip6_tunnel_init(struct net_device *dev);
67static void ipip6_tunnel_setup(struct net_device *dev);
68
69static struct net_device *ipip6_fb_tunnel_dev;
70
71static struct ip_tunnel *tunnels_r_l[HASH_SIZE];
72static struct ip_tunnel *tunnels_r[HASH_SIZE];
73static struct ip_tunnel *tunnels_l[HASH_SIZE];
74static struct ip_tunnel *tunnels_wc[1];
75static struct ip_tunnel **tunnels[4] = { tunnels_wc, tunnels_l, tunnels_r, tunnels_r_l };
76
77static DEFINE_RWLOCK(ipip6_lock);
78
e69a4adc 79static 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 103static 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		 121static inline struct ip_tunnel **ipip6_bucket(struct ip_tunnel *t)
122{
123 return __ipip6_bucket(&t->parms);
124}
125
1da177e4
LT		 126static 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
140static 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
150static 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		 194failed_free:
195 free_netdev(dev);
1da177e4
LT		 196failed:
197 return NULL;
198}
199
fadf6bf0
TF		 200static struct ip_tunnel_prl_entry *
201ipip6_tunnel_locate_prl(struct ip_tunnel *t, __be32 addr)
202{
203 struct ip_tunnel_prl_entry *p = (struct ip_tunnel_prl_entry *)NULL;
204
205 for (p = t->prl; p; p = p->next)
206 if (p->entry.addr == addr)
207 break;
208 return p;
209
210}
211
212static int
213ipip6_tunnel_add_prl(struct ip_tunnel *t, struct ip_tunnel_prl *a, int chg)
214{
215 struct ip_tunnel_prl_entry *p;
216
217 for (p = t->prl; p; p = p->next) {
218 if (p->entry.addr == a->addr) {
219 if (chg) {
220 p->entry = *a;
221 return 0;
222 }
223 return -EEXIST;
224 }
225 }
226
227 if (chg)
228 return -ENXIO;
229
230 p = kzalloc(sizeof(struct ip_tunnel_prl_entry), GFP_KERNEL);
231 if (!p)
232 return -ENOBUFS;
233
234 p->entry = *a;
235 p->next = t->prl;
236 t->prl = p;
237 return 0;
238}
239
240static int
241ipip6_tunnel_del_prl(struct ip_tunnel *t, struct ip_tunnel_prl *a)
242{
243 struct ip_tunnel_prl_entry *x, **p;
244
245 if (a) {
246 for (p = &t->prl; *p; p = &(*p)->next) {
247 if ((*p)->entry.addr == a->addr) {
248 x = *p;
249 *p = x->next;
250 kfree(x);
251 return 0;
252 }
253 }
254 return -ENXIO;
255 } else {
256 while (t->prl) {
257 x = t->prl;
258 t->prl = t->prl->next;
259 kfree(x);
260 }
261 }
262 return 0;
263}
264
265/* copied directly from anycast.c */
266static int
267ipip6_onlink(struct in6_addr *addr, struct net_device *dev)
268{
269 struct inet6_dev *idev;
270 struct inet6_ifaddr *ifa;
271 int onlink;
272
273 onlink = 0;
274 rcu_read_lock();
275 idev = __in6_dev_get(dev);
276 if (idev) {
277 read_lock_bh(&idev->lock);
278 for (ifa=idev->addr_list; ifa; ifa=ifa->if_next) {
279 onlink = ipv6_prefix_equal(addr, &ifa->addr,
280 ifa->prefix_len);
281 if (onlink)
282 break;
283 }
284 read_unlock_bh(&idev->lock);
285 }
286 rcu_read_unlock();
287 return onlink;
288}
289
290static int
291isatap_chksrc(struct sk_buff *skb, struct iphdr *iph, struct ip_tunnel *t)
292{
293 struct ip_tunnel_prl_entry *p = ipip6_tunnel_locate_prl(t, iph->saddr);
294 int ok = 1;
295
296 if (p) {
297 if (p->entry.flags & PRL_DEFAULT)
298 skb->ndisc_nodetype = NDISC_NODETYPE_DEFAULT;
299 else
300 skb->ndisc_nodetype = NDISC_NODETYPE_NODEFAULT;
301 } else {
302 struct in6_addr *addr6 = &ipv6_hdr(skb)->saddr;
303 if (ipv6_addr_is_isatap(addr6) &&
304 (addr6->s6_addr32[3] == iph->saddr) &&
305 ipip6_onlink(addr6, t->dev))
306 skb->ndisc_nodetype = NDISC_NODETYPE_HOST;
307 else
308 ok = 0;
309 }
310 return ok;
311}
312
1da177e4
LT		 313static void ipip6_tunnel_uninit(struct net_device *dev)
314{
315 if (dev == ipip6_fb_tunnel_dev) {
316 write_lock_bh(&ipip6_lock);
317 tunnels_wc[0] = NULL;
318 write_unlock_bh(&ipip6_lock);
319 dev_put(dev);
320 } else {
2941a486 321 ipip6_tunnel_unlink(netdev_priv(dev));
fadf6bf0 322 ipip6_tunnel_del_prl(netdev_priv(dev), 0);
1da177e4
LT		 323 dev_put(dev);
324 }
325}
326
327
c73cb5a2 328static int ipip6_err(struct sk_buff *skb, u32 info)
1da177e4
LT		 329{
330#ifndef I_WISH_WORLD_WERE_PERFECT
331
332/* It is not :-( All the routers (except for Linux) return only
333 8 bytes of packet payload. It means, that precise relaying of
334 ICMP in the real Internet is absolutely infeasible.
335 */
336 struct iphdr *iph = (struct iphdr*)skb->data;
88c7664f
ACM		 337 const int type = icmp_hdr(skb)->type;
338 const int code = icmp_hdr(skb)->code;
1da177e4 339 struct ip_tunnel *t;
c73cb5a2 340 int err;
1da177e4
LT		 341
342 switch (type) {
343 default:
344 case ICMP_PARAMETERPROB:
c73cb5a2 345 return 0;
1da177e4
LT		 346
347 case ICMP_DEST_UNREACH:
348 switch (code) {
349 case ICMP_SR_FAILED:
350 case ICMP_PORT_UNREACH:
351 /* Impossible event. */
c73cb5a2 352 return 0;
1da177e4
LT		 353 case ICMP_FRAG_NEEDED:
354 /* Soft state for pmtu is maintained by IP core. */
c73cb5a2 355 return 0;
1da177e4
LT		 356 default:
357 /* All others are translated to HOST_UNREACH.
358 rfc2003 contains "deep thoughts" about NET_UNREACH,
359 I believe they are just ether pollution. --ANK
360 */
361 break;
362 }
363 break;
364 case ICMP_TIME_EXCEEDED:
365 if (code != ICMP_EXC_TTL)
c73cb5a2 366 return 0;
1da177e4
LT		 367 break;
368 }
369
c73cb5a2
KM		 370 err = -ENOENT;
371
1da177e4
LT		 372 read_lock(&ipip6_lock);
373 t = ipip6_tunnel_lookup(iph->daddr, iph->saddr);
374 if (t == NULL || t->parms.iph.daddr == 0)
375 goto out;
c73cb5a2
KM		 376
377 err = 0;
1da177e4
LT		 378 if (t->parms.iph.ttl == 0 && type == ICMP_TIME_EXCEEDED)
379 goto out;
380
381 if (jiffies - t->err_time < IPTUNNEL_ERR_TIMEO)
382 t->err_count++;
383 else
384 t->err_count = 1;
385 t->err_time = jiffies;
386out:
387 read_unlock(&ipip6_lock);
c73cb5a2 388 return err;
1da177e4
LT		 389#else
390 struct iphdr *iph = (struct iphdr*)dp;
391 int hlen = iph->ihl<<2;
392 struct ipv6hdr *iph6;
88c7664f
ACM		 393 const int type = icmp_hdr(skb)->type;
394 const int code = icmp_hdr(skb)->code;
1da177e4
LT		 395 int rel_type = 0;
396 int rel_code = 0;
397 int rel_info = 0;
398 struct sk_buff *skb2;
399 struct rt6_info *rt6i;
400
401 if (len < hlen + sizeof(struct ipv6hdr))
402 return;
403 iph6 = (struct ipv6hdr*)(dp + hlen);
404
405 switch (type) {
406 default:
407 return;
408 case ICMP_PARAMETERPROB:
88c7664f 409 if (icmp_hdr(skb)->un.gateway < hlen)
1da177e4
LT		 410 return;
411
412 /* So... This guy found something strange INSIDE encapsulated
413 packet. Well, he is fool, but what can we do ?
414 */
415 rel_type = ICMPV6_PARAMPROB;
88c7664f 416 rel_info = icmp_hdr(skb)->un.gateway - hlen;
1da177e4
LT		 417 break;
418
419 case ICMP_DEST_UNREACH:
420 switch (code) {
421 case ICMP_SR_FAILED:
422 case ICMP_PORT_UNREACH:
423 /* Impossible event. */
424 return;
425 case ICMP_FRAG_NEEDED:
426 /* Too complicated case ... */
427 return;
428 default:
429 /* All others are translated to HOST_UNREACH.
430 rfc2003 contains "deep thoughts" about NET_UNREACH,
431 I believe, it is just ether pollution. --ANK
432 */
433 rel_type = ICMPV6_DEST_UNREACH;
434 rel_code = ICMPV6_ADDR_UNREACH;
435 break;
436 }
437 break;
438 case ICMP_TIME_EXCEEDED:
439 if (code != ICMP_EXC_TTL)
440 return;
441 rel_type = ICMPV6_TIME_EXCEED;
442 rel_code = ICMPV6_EXC_HOPLIMIT;
443 break;
444 }
445
446 /* Prepare fake skb to feed it to icmpv6_send */
447 skb2 = skb_clone(skb, GFP_ATOMIC);
448 if (skb2 == NULL)
c73cb5a2 449 return 0;
1da177e4
LT		 450 dst_release(skb2->dst);
451 skb2->dst = NULL;
452 skb_pull(skb2, skb->data - (u8*)iph6);
c1d2bbe1 453 skb_reset_network_header(skb2);
1da177e4
LT		 454
455 /* Try to guess incoming interface */
606a2b48 456 rt6i = rt6_lookup(&init_net, &iph6->saddr, NULL, NULL, 0);
1da177e4
LT		 457 if (rt6i && rt6i->rt6i_dev) {
458 skb2->dev = rt6i->rt6i_dev;
459
606a2b48 460 rt6i = rt6_lookup(&init_net, &iph6->daddr, &iph6->saddr, NULL, 0);
1da177e4
LT		 461
462 if (rt6i && rt6i->rt6i_dev && rt6i->rt6i_dev->type == ARPHRD_SIT) {
2941a486 463 struct ip_tunnel *t = netdev_priv(rt6i->rt6i_dev);
1da177e4
LT		 464 if (rel_type == ICMPV6_TIME_EXCEED && t->parms.iph.ttl) {
465 rel_type = ICMPV6_DEST_UNREACH;
466 rel_code = ICMPV6_ADDR_UNREACH;
467 }
468 icmpv6_send(skb2, rel_type, rel_code, rel_info, skb2->dev);
469 }
470 }
471 kfree_skb(skb2);
c73cb5a2 472 return 0;
1da177e4
LT		 473#endif
474}
475
476static inline void ipip6_ecn_decapsulate(struct iphdr *iph, struct sk_buff *skb)
477{
478 if (INET_ECN_is_ce(iph->tos))
0660e03f 479 IP6_ECN_set_ce(ipv6_hdr(skb));
1da177e4
LT		 480}
481
482static int ipip6_rcv(struct sk_buff *skb)
483{
484 struct iphdr *iph;
485 struct ip_tunnel *tunnel;
486
487 if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
488 goto out;
489
eddc9ec5 490 iph = ip_hdr(skb);
1da177e4
LT		 491
492 read_lock(&ipip6_lock);
493 if ((tunnel = ipip6_tunnel_lookup(iph->saddr, iph->daddr)) != NULL) {
494 secpath_reset(skb);
b0e380b1 495 skb->mac_header = skb->network_header;
c1d2bbe1 496 skb_reset_network_header(skb);
8cdfab8a 497 IPCB(skb)->flags = 0;
1da177e4
LT		 498 skb->protocol = htons(ETH_P_IPV6);
499 skb->pkt_type = PACKET_HOST;
c7dc89c0
FT		 500
501 if ((tunnel->dev->priv_flags & IFF_ISATAP) &&
fadf6bf0 502 !isatap_chksrc(skb, iph, tunnel)) {
c7dc89c0
FT		 503 tunnel->stat.rx_errors++;
504 read_unlock(&ipip6_lock);
505 kfree_skb(skb);
506 return 0;
507 }
1da177e4
LT		 508 tunnel->stat.rx_packets++;
509 tunnel->stat.rx_bytes += skb->len;
510 skb->dev = tunnel->dev;
511 dst_release(skb->dst);
512 skb->dst = NULL;
513 nf_reset(skb);
514 ipip6_ecn_decapsulate(iph, skb);
515 netif_rx(skb);
516 read_unlock(&ipip6_lock);
517 return 0;
518 }
519
45af08be 520 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PORT_UNREACH, 0);
1da177e4
LT		 521 kfree_skb(skb);
522 read_unlock(&ipip6_lock);
523out:
524 return 0;
525}
526
527/* Returns the embedded IPv4 address if the IPv6 address
528 comes from 6to4 (RFC 3056) addr space */
529
e69a4adc 530static inline __be32 try_6to4(struct in6_addr *v6dst)
1da177e4 531{
e69a4adc 532 __be32 dst = 0;
1da177e4
LT		 533
534 if (v6dst->s6_addr16[0] == htons(0x2002)) {
1ab1457c 535 /* 6to4 v6 addr has 16 bits prefix, 32 v4addr, 16 SLA, ... */
1da177e4
LT		 536 memcpy(&dst, &v6dst->s6_addr16[1], 4);
537 }
538 return dst;
539}
540
541/*
542 * This function assumes it is being called from dev_queue_xmit()
543 * and that skb is filled properly by that function.
544 */
545
546static int ipip6_tunnel_xmit(struct sk_buff *skb, struct net_device *dev)
547{
2941a486 548 struct ip_tunnel *tunnel = netdev_priv(dev);
1da177e4
LT		 549 struct net_device_stats *stats = &tunnel->stat;
550 struct iphdr *tiph = &tunnel->parms.iph;
0660e03f 551 struct ipv6hdr *iph6 = ipv6_hdr(skb);
1da177e4
LT		 552 u8 tos = tunnel->parms.iph.tos;
553 struct rtable *rt; /* Route to the other host */
554 struct net_device *tdev; /* Device to other host */
555 struct iphdr *iph; /* Our new IP header */
c2636b4d 556 unsigned int max_headroom; /* The extra header space needed */
e69a4adc 557 __be32 dst = tiph->daddr;
1da177e4 558 int mtu;
1ab1457c 559 struct in6_addr *addr6;
1da177e4
LT		 560 int addr_type;
561
562 if (tunnel->recursion++) {
563 tunnel->stat.collisions++;
564 goto tx_error;
565 }
566
567 if (skb->protocol != htons(ETH_P_IPV6))
568 goto tx_error;
569
c7dc89c0
FT		 570 /* ISATAP (RFC4214) - must come before 6to4 */
571 if (dev->priv_flags & IFF_ISATAP) {
572 struct neighbour *neigh = NULL;
573
574 if (skb->dst)
575 neigh = skb->dst->neighbour;
576
577 if (neigh == NULL) {
578 if (net_ratelimit())
579 printk(KERN_DEBUG "sit: nexthop == NULL\n");
580 goto tx_error;
581 }
582
583 addr6 = (struct in6_addr*)&neigh->primary_key;
584 addr_type = ipv6_addr_type(addr6);
585
586 if ((addr_type & IPV6_ADDR_UNICAST) &&
587 ipv6_addr_is_isatap(addr6))
588 dst = addr6->s6_addr32[3];
589 else
590 goto tx_error;
591 }
592
1da177e4
LT		 593 if (!dst)
594 dst = try_6to4(&iph6->daddr);
595
596 if (!dst) {
597 struct neighbour *neigh = NULL;
598
599 if (skb->dst)
600 neigh = skb->dst->neighbour;
601
602 if (neigh == NULL) {
603 if (net_ratelimit())
604 printk(KERN_DEBUG "sit: nexthop == NULL\n");
605 goto tx_error;
606 }
607
608 addr6 = (struct in6_addr*)&neigh->primary_key;
609 addr_type = ipv6_addr_type(addr6);
610
611 if (addr_type == IPV6_ADDR_ANY) {
0660e03f 612 addr6 = &ipv6_hdr(skb)->daddr;
1da177e4
LT		 613 addr_type = ipv6_addr_type(addr6);
614 }
615
616 if ((addr_type & IPV6_ADDR_COMPATv4) == 0)
617 goto tx_error_icmp;
618
619 dst = addr6->s6_addr32[3];
620 }
621
622 {
623 struct flowi fl = { .nl_u = { .ip4_u =
624 { .daddr = dst,
625 .saddr = tiph->saddr,
626 .tos = RT_TOS(tos) } },
627 .oif = tunnel->parms.link,
628 .proto = IPPROTO_IPV6 };
f206351a 629 if (ip_route_output_key(&init_net, &rt, &fl)) {
1da177e4
LT		 630 tunnel->stat.tx_carrier_errors++;
631 goto tx_error_icmp;
632 }
633 }
634 if (rt->rt_type != RTN_UNICAST) {
635 ip_rt_put(rt);
636 tunnel->stat.tx_carrier_errors++;
637 goto tx_error_icmp;
638 }
639 tdev = rt->u.dst.dev;
640
641 if (tdev == dev) {
642 ip_rt_put(rt);
643 tunnel->stat.collisions++;
644 goto tx_error;
645 }
646
647 if (tiph->frag_off)
648 mtu = dst_mtu(&rt->u.dst) - sizeof(struct iphdr);
649 else
650 mtu = skb->dst ? dst_mtu(skb->dst) : dev->mtu;
651
652 if (mtu < 68) {
653 tunnel->stat.collisions++;
654 ip_rt_put(rt);
655 goto tx_error;
656 }
657 if (mtu < IPV6_MIN_MTU)
658 mtu = IPV6_MIN_MTU;
659 if (tunnel->parms.iph.daddr && skb->dst)
660 skb->dst->ops->update_pmtu(skb->dst, mtu);
661
662 if (skb->len > mtu) {
663 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu, dev);
664 ip_rt_put(rt);
665 goto tx_error;
666 }
667
668 if (tunnel->err_count > 0) {
669 if (jiffies - tunnel->err_time < IPTUNNEL_ERR_TIMEO) {
670 tunnel->err_count--;
671 dst_link_failure(skb);
672 } else
673 tunnel->err_count = 0;
674 }
675
676 /*
677 * Okay, now see if we can stuff it in the buffer as-is.
678 */
679 max_headroom = LL_RESERVED_SPACE(tdev)+sizeof(struct iphdr);
680
cfbba49d
PM		 681 if (skb_headroom(skb) < max_headroom || skb_shared(skb) ||
682 (skb_cloned(skb) && !skb_clone_writable(skb, 0))) {
1da177e4
LT		 683 struct sk_buff *new_skb = skb_realloc_headroom(skb, max_headroom);
684 if (!new_skb) {
685 ip_rt_put(rt);
1ab1457c 686 stats->tx_dropped++;
1da177e4
LT		 687 dev_kfree_skb(skb);
688 tunnel->recursion--;
689 return 0;
690 }
691 if (skb->sk)
692 skb_set_owner_w(new_skb, skb->sk);
693 dev_kfree_skb(skb);
694 skb = new_skb;
0660e03f 695 iph6 = ipv6_hdr(skb);
1da177e4
LT		 696 }
697
b0e380b1 698 skb->transport_header = skb->network_header;
e2d1bca7
ACM		 699 skb_push(skb, sizeof(struct iphdr));
700 skb_reset_network_header(skb);
1da177e4 701 memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
8cdfab8a 702 IPCB(skb)->flags = 0;
1da177e4
LT		 703 dst_release(skb->dst);
704 skb->dst = &rt->u.dst;
705
706 /*
707 * Push down and install the IPIP header.
708 */
709
eddc9ec5 710 iph = ip_hdr(skb);
1da177e4
LT		 711 iph->version = 4;
712 iph->ihl = sizeof(struct iphdr)>>2;
713 if (mtu > IPV6_MIN_MTU)
714 iph->frag_off = htons(IP_DF);
715 else
716 iph->frag_off = 0;
717
718 iph->protocol = IPPROTO_IPV6;
719 iph->tos = INET_ECN_encapsulate(tos, ipv6_get_dsfield(iph6));
720 iph->daddr = rt->rt_dst;
721 iph->saddr = rt->rt_src;
722
723 if ((iph->ttl = tiph->ttl) == 0)
724 iph->ttl = iph6->hop_limit;
725
726 nf_reset(skb);
727
728 IPTUNNEL_XMIT();
729 tunnel->recursion--;
730 return 0;
731
732tx_error_icmp:
733 dst_link_failure(skb);
734tx_error:
735 stats->tx_errors++;
736 dev_kfree_skb(skb);
737 tunnel->recursion--;
738 return 0;
739}
740
8a4a50f9
MS		 741static void ipip6_tunnel_bind_dev(struct net_device *dev)
742{
743 struct net_device *tdev = NULL;
744 struct ip_tunnel *tunnel;
745 struct iphdr *iph;
746
747 tunnel = netdev_priv(dev);
748 iph = &tunnel->parms.iph;
749
750 if (iph->daddr) {
751 struct flowi fl = { .nl_u = { .ip4_u =
752 { .daddr = iph->daddr,
753 .saddr = iph->saddr,
754 .tos = RT_TOS(iph->tos) } },
755 .oif = tunnel->parms.link,
756 .proto = IPPROTO_IPV6 };
757 struct rtable *rt;
f206351a 758 if (!ip_route_output_key(&init_net, &rt, &fl)) {
8a4a50f9
MS		 759 tdev = rt->u.dst.dev;
760 ip_rt_put(rt);
761 }
762 dev->flags |= IFF_POINTOPOINT;
763 }
764
765 if (!tdev && tunnel->parms.link)
766 tdev = __dev_get_by_index(&init_net, tunnel->parms.link);
767
768 if (tdev) {
769 dev->hard_header_len = tdev->hard_header_len + sizeof(struct iphdr);
770 dev->mtu = tdev->mtu - sizeof(struct iphdr);
771 if (dev->mtu < IPV6_MIN_MTU)
772 dev->mtu = IPV6_MIN_MTU;
773 }
774 dev->iflink = tunnel->parms.link;
775}
776
1da177e4
LT		 777static int
778ipip6_tunnel_ioctl (struct net_device *dev, struct ifreq *ifr, int cmd)
779{
780 int err = 0;
781 struct ip_tunnel_parm p;
fadf6bf0 782 struct ip_tunnel_prl prl;
1da177e4
LT		 783 struct ip_tunnel *t;
784
785 switch (cmd) {
786 case SIOCGETTUNNEL:
787 t = NULL;
788 if (dev == ipip6_fb_tunnel_dev) {
789 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) {
790 err = -EFAULT;
791 break;
792 }
793 t = ipip6_tunnel_locate(&p, 0);
794 }
795 if (t == NULL)
2941a486 796 t = netdev_priv(dev);
1da177e4
LT		 797 memcpy(&p, &t->parms, sizeof(p));
798 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
799 err = -EFAULT;
800 break;
801
802 case SIOCADDTUNNEL:
803 case SIOCCHGTUNNEL:
804 err = -EPERM;
805 if (!capable(CAP_NET_ADMIN))
806 goto done;
807
808 err = -EFAULT;
809 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
810 goto done;
811
812 err = -EINVAL;
813 if (p.iph.version != 4 || p.iph.protocol != IPPROTO_IPV6 ||
814 p.iph.ihl != 5 || (p.iph.frag_off&htons(~IP_DF)))
815 goto done;
816 if (p.iph.ttl)
817 p.iph.frag_off |= htons(IP_DF);
818
819 t = ipip6_tunnel_locate(&p, cmd == SIOCADDTUNNEL);
820
821 if (dev != ipip6_fb_tunnel_dev && cmd == SIOCCHGTUNNEL) {
822 if (t != NULL) {
823 if (t->dev != dev) {
824 err = -EEXIST;
825 break;
826 }
827 } else {
828 if (((dev->flags&IFF_POINTOPOINT) && !p.iph.daddr) ||
829 (!(dev->flags&IFF_POINTOPOINT) && p.iph.daddr)) {
830 err = -EINVAL;
831 break;
832 }
2941a486 833 t = netdev_priv(dev);
1da177e4
LT		 834 ipip6_tunnel_unlink(t);
835 t->parms.iph.saddr = p.iph.saddr;
836 t->parms.iph.daddr = p.iph.daddr;
837 memcpy(dev->dev_addr, &p.iph.saddr, 4);
838 memcpy(dev->broadcast, &p.iph.daddr, 4);
839 ipip6_tunnel_link(t);
840 netdev_state_change(dev);
841 }
842 }
843
844 if (t) {
845 err = 0;
846 if (cmd == SIOCCHGTUNNEL) {
847 t->parms.iph.ttl = p.iph.ttl;
848 t->parms.iph.tos = p.iph.tos;
8a4a50f9
MS		 849 if (t->parms.link != p.link) {
850 t->parms.link = p.link;
851 ipip6_tunnel_bind_dev(dev);
852 netdev_state_change(dev);
853 }
1da177e4
LT		 854 }
855 if (copy_to_user(ifr->ifr_ifru.ifru_data, &t->parms, sizeof(p)))
856 err = -EFAULT;
857 } else
858 err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
859 break;
860
861 case SIOCDELTUNNEL:
862 err = -EPERM;
863 if (!capable(CAP_NET_ADMIN))
864 goto done;
865
866 if (dev == ipip6_fb_tunnel_dev) {
867 err = -EFAULT;
868 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
869 goto done;
870 err = -ENOENT;
871 if ((t = ipip6_tunnel_locate(&p, 0)) == NULL)
872 goto done;
873 err = -EPERM;
2941a486 874 if (t == netdev_priv(ipip6_fb_tunnel_dev))
1da177e4
LT		 875 goto done;
876 dev = t->dev;
877 }
22f8cde5
SH		 878 unregister_netdevice(dev);
879 err = 0;
1da177e4
LT		 880 break;
881
fadf6bf0
TF		 882 case SIOCADDPRL:
883 case SIOCDELPRL:
884 case SIOCCHGPRL:
885 err = -EPERM;
886 if (!capable(CAP_NET_ADMIN))
887 goto done;
888 err = -EINVAL;
889 if (dev == ipip6_fb_tunnel_dev)
890 goto done;
891 err = -EFAULT;
892 if (copy_from_user(&prl, ifr->ifr_ifru.ifru_data, sizeof(prl)))
893 goto done;
894 err = -ENOENT;
895 if (!(t = netdev_priv(dev)))
896 goto done;
897
898 ipip6_tunnel_unlink(t);
899 if (cmd == SIOCDELPRL)
900 err = ipip6_tunnel_del_prl(t, &prl);
901 else
902 err = ipip6_tunnel_add_prl(t, &prl, cmd == SIOCCHGPRL);
903 ipip6_tunnel_link(t);
904 netdev_state_change(dev);
905 break;
906
1da177e4
LT		 907 default:
908 err = -EINVAL;
909 }
910
911done:
912 return err;
913}
914
915static struct net_device_stats *ipip6_tunnel_get_stats(struct net_device *dev)
916{
2941a486 917 return &(((struct ip_tunnel*)netdev_priv(dev))->stat);
1da177e4
LT		 918}
919
920static int ipip6_tunnel_change_mtu(struct net_device *dev, int new_mtu)
921{
922 if (new_mtu < IPV6_MIN_MTU || new_mtu > 0xFFF8 - sizeof(struct iphdr))
923 return -EINVAL;
924 dev->mtu = new_mtu;
925 return 0;
926}
927
928static void ipip6_tunnel_setup(struct net_device *dev)
929{
1da177e4
LT		 930 dev->uninit = ipip6_tunnel_uninit;
931 dev->destructor = free_netdev;
932 dev->hard_start_xmit = ipip6_tunnel_xmit;
933 dev->get_stats = ipip6_tunnel_get_stats;
934 dev->do_ioctl = ipip6_tunnel_ioctl;
935 dev->change_mtu = ipip6_tunnel_change_mtu;
936
937 dev->type = ARPHRD_SIT;
938 dev->hard_header_len = LL_MAX_HEADER + sizeof(struct iphdr);
46f25dff 939 dev->mtu = ETH_DATA_LEN - sizeof(struct iphdr);
1da177e4
LT		 940 dev->flags = IFF_NOARP;
941 dev->iflink = 0;
942 dev->addr_len = 4;
943}
944
945static int ipip6_tunnel_init(struct net_device *dev)
946{
1da177e4 947 struct ip_tunnel *tunnel;
1da177e4 948
2941a486 949 tunnel = netdev_priv(dev);
1da177e4
LT		 950
951 tunnel->dev = dev;
952 strcpy(tunnel->parms.name, dev->name);
953
954 memcpy(dev->dev_addr, &tunnel->parms.iph.saddr, 4);
955 memcpy(dev->broadcast, &tunnel->parms.iph.daddr, 4);
956
8a4a50f9 957 ipip6_tunnel_bind_dev(dev);
1da177e4
LT		 958
959 return 0;
960}
961
20380731 962static int __init ipip6_fb_tunnel_init(struct net_device *dev)
1da177e4 963{
2941a486 964 struct ip_tunnel *tunnel = netdev_priv(dev);
1da177e4
LT		 965 struct iphdr *iph = &tunnel->parms.iph;
966
967 tunnel->dev = dev;
968 strcpy(tunnel->parms.name, dev->name);
969
970 iph->version = 4;
971 iph->protocol = IPPROTO_IPV6;
972 iph->ihl = 5;
973 iph->ttl = 64;
974
975 dev_hold(dev);
976 tunnels_wc[0] = tunnel;
977 return 0;
978}
979
c73cb5a2 980static struct xfrm_tunnel sit_handler = {
1da177e4
LT		 981 .handler = ipip6_rcv,
982 .err_handler = ipip6_err,
c73cb5a2 983 .priority = 1,
1da177e4
LT		 984};
985
db44575f
AK		 986static void __exit sit_destroy_tunnels(void)
987{
988 int prio;
989
990 for (prio = 1; prio < 4; prio++) {
991 int h;
992 for (h = 0; h < HASH_SIZE; h++) {
993 struct ip_tunnel *t;
994 while ((t = tunnels[prio][h]) != NULL)
995 unregister_netdevice(t->dev);
996 }
997 }
998}
999
89c89458 1000static void __exit sit_cleanup(void)
1da177e4 1001{
c73cb5a2 1002 xfrm4_tunnel_deregister(&sit_handler, AF_INET6);
db44575f
AK		 1003
1004 rtnl_lock();
1005 sit_destroy_tunnels();
1006 unregister_netdevice(ipip6_fb_tunnel_dev);
1007 rtnl_unlock();
1da177e4
LT		 1008}
1009
89c89458 1010static int __init sit_init(void)
1da177e4
LT		 1011{
1012 int err;
1013
1014 printk(KERN_INFO "IPv6 over IPv4 tunneling driver\n");
1015
c73cb5a2 1016 if (xfrm4_tunnel_register(&sit_handler, AF_INET6) < 0) {
1da177e4
LT		 1017 printk(KERN_INFO "sit init: Can't add protocol\n");
1018 return -EAGAIN;
1019 }
1020
1ab1457c 1021 ipip6_fb_tunnel_dev = alloc_netdev(sizeof(struct ip_tunnel), "sit0",
1da177e4
LT		 1022 ipip6_tunnel_setup);
1023 if (!ipip6_fb_tunnel_dev) {
1024 err = -ENOMEM;
1025 goto err1;
1026 }
1027
1028 ipip6_fb_tunnel_dev->init = ipip6_fb_tunnel_init;
1029
1030 if ((err = register_netdev(ipip6_fb_tunnel_dev)))
1031 goto err2;
1032
1033 out:
1034 return err;
1035 err2:
1036 free_netdev(ipip6_fb_tunnel_dev);
1037 err1:
c73cb5a2 1038 xfrm4_tunnel_deregister(&sit_handler, AF_INET6);
1da177e4
LT		 1039 goto out;
1040}
989e5b96
JR		 1041
1042module_init(sit_init);
1043module_exit(sit_cleanup);
39c85086 1044MODULE_LICENSE("GPL");
daccff02 1045MODULE_ALIAS("sit0");
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