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Diffstat (limited to 'net/ipv4/ip_gre.c')
-rw-r--r--net/ipv4/ip_gre.c146
1 files changed, 1 insertions, 145 deletions
diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c
index 2ada033406de..4342cba4ff82 100644
--- a/net/ipv4/ip_gre.c
+++ b/net/ipv4/ip_gre.c
@@ -313,9 +313,8 @@ static void ipgre_tunnel_uninit(struct net_device *dev)
313 313
314static void ipgre_err(struct sk_buff *skb, u32 info) 314static void ipgre_err(struct sk_buff *skb, u32 info)
315{ 315{
316#ifndef I_WISH_WORLD_WERE_PERFECT
317 316
318/* It is not :-( All the routers (except for Linux) return only 317/* All the routers (except for Linux) return only
319 8 bytes of packet payload. It means, that precise relaying of 318 8 bytes of packet payload. It means, that precise relaying of
320 ICMP in the real Internet is absolutely infeasible. 319 ICMP in the real Internet is absolutely infeasible.
321 320
@@ -398,149 +397,6 @@ static void ipgre_err(struct sk_buff *skb, u32 info)
398out: 397out:
399 read_unlock(&ipgre_lock); 398 read_unlock(&ipgre_lock);
400 return; 399 return;
401#else
402 struct iphdr *iph = (struct iphdr*)dp;
403 struct iphdr *eiph;
404 __be16 *p = (__be16*)(dp+(iph->ihl<<2));
405 const int type = icmp_hdr(skb)->type;
406 const int code = icmp_hdr(skb)->code;
407 int rel_type = 0;
408 int rel_code = 0;
409 __be32 rel_info = 0;
410 __u32 n = 0;
411 __be16 flags;
412 int grehlen = (iph->ihl<<2) + 4;
413 struct sk_buff *skb2;
414 struct flowi fl;
415 struct rtable *rt;
416
417 if (p[1] != htons(ETH_P_IP))
418 return;
419
420 flags = p[0];
421 if (flags&(GRE_CSUM|GRE_KEY|GRE_SEQ|GRE_ROUTING|GRE_VERSION)) {
422 if (flags&(GRE_VERSION|GRE_ROUTING))
423 return;
424 if (flags&GRE_CSUM)
425 grehlen += 4;
426 if (flags&GRE_KEY)
427 grehlen += 4;
428 if (flags&GRE_SEQ)
429 grehlen += 4;
430 }
431 if (len < grehlen + sizeof(struct iphdr))
432 return;
433 eiph = (struct iphdr*)(dp + grehlen);
434
435 switch (type) {
436 default:
437 return;
438 case ICMP_PARAMETERPROB:
439 n = ntohl(icmp_hdr(skb)->un.gateway) >> 24;
440 if (n < (iph->ihl<<2))
441 return;
442
443 /* So... This guy found something strange INSIDE encapsulated
444 packet. Well, he is fool, but what can we do ?
445 */
446 rel_type = ICMP_PARAMETERPROB;
447 n -= grehlen;
448 rel_info = htonl(n << 24);
449 break;
450
451 case ICMP_DEST_UNREACH:
452 switch (code) {
453 case ICMP_SR_FAILED:
454 case ICMP_PORT_UNREACH:
455 /* Impossible event. */
456 return;
457 case ICMP_FRAG_NEEDED:
458 /* And it is the only really necessary thing :-) */
459 n = ntohs(icmp_hdr(skb)->un.frag.mtu);
460 if (n < grehlen+68)
461 return;
462 n -= grehlen;
463 /* BSD 4.2 MORE DOES NOT EXIST IN NATURE. */
464 if (n > ntohs(eiph->tot_len))
465 return;
466 rel_info = htonl(n);
467 break;
468 default:
469 /* All others are translated to HOST_UNREACH.
470 rfc2003 contains "deep thoughts" about NET_UNREACH,
471 I believe, it is just ether pollution. --ANK
472 */
473 rel_type = ICMP_DEST_UNREACH;
474 rel_code = ICMP_HOST_UNREACH;
475 break;
476 }
477 break;
478 case ICMP_TIME_EXCEEDED:
479 if (code != ICMP_EXC_TTL)
480 return;
481 break;
482 }
483
484 /* Prepare fake skb to feed it to icmp_send */
485 skb2 = skb_clone(skb, GFP_ATOMIC);
486 if (skb2 == NULL)
487 return;
488 dst_release(skb2->dst);
489 skb2->dst = NULL;
490 skb_pull(skb2, skb->data - (u8*)eiph);
491 skb_reset_network_header(skb2);
492
493 /* Try to guess incoming interface */
494 memset(&fl, 0, sizeof(fl));
495 fl.fl4_dst = eiph->saddr;
496 fl.fl4_tos = RT_TOS(eiph->tos);
497 fl.proto = IPPROTO_GRE;
498 if (ip_route_output_key(dev_net(skb->dev), &rt, &fl)) {
499 kfree_skb(skb2);
500 return;
501 }
502 skb2->dev = rt->u.dst.dev;
503
504 /* route "incoming" packet */
505 if (rt->rt_flags&RTCF_LOCAL) {
506 ip_rt_put(rt);
507 rt = NULL;
508 fl.fl4_dst = eiph->daddr;
509 fl.fl4_src = eiph->saddr;
510 fl.fl4_tos = eiph->tos;
511 if (ip_route_output_key(dev_net(skb->dev), &rt, &fl) ||
512 rt->u.dst.dev->type != ARPHRD_IPGRE) {
513 ip_rt_put(rt);
514 kfree_skb(skb2);
515 return;
516 }
517 } else {
518 ip_rt_put(rt);
519 if (ip_route_input(skb2, eiph->daddr, eiph->saddr, eiph->tos, skb2->dev) ||
520 skb2->dst->dev->type != ARPHRD_IPGRE) {
521 kfree_skb(skb2);
522 return;
523 }
524 }
525
526 /* change mtu on this route */
527 if (type == ICMP_DEST_UNREACH && code == ICMP_FRAG_NEEDED) {
528 if (n > dst_mtu(skb2->dst)) {
529 kfree_skb(skb2);
530 return;
531 }
532 skb2->dst->ops->update_pmtu(skb2->dst, n);
533 } else if (type == ICMP_TIME_EXCEEDED) {
534 struct ip_tunnel *t = netdev_priv(skb2->dev);
535 if (t->parms.iph.ttl) {
536 rel_type = ICMP_DEST_UNREACH;
537 rel_code = ICMP_HOST_UNREACH;
538 }
539 }
540
541 icmp_send(skb2, rel_type, rel_code, rel_info);
542 kfree_skb(skb2);
543#endif
544} 400}
545 401
546static inline void ipgre_ecn_decapsulate(struct iphdr *iph, struct sk_buff *skb) 402static inline void ipgre_ecn_decapsulate(struct iphdr *iph, struct sk_buff *skb)