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USB: remove use of the bus rwsem, as it doesn't really protect anything.
[linux/fpc-iii.git] / net / ipv6 / ip6_output.c
blobf508171bab735b5e1901caa51bfff0248129e2c7
1 /*
2 * IPv6 output functions
3 * Linux INET6 implementation
4 *
5 * Authors:
6 * Pedro Roque <roque@di.fc.ul.pt>
7 *
8 * $Id: ip6_output.c,v 1.34 2002/02/01 22:01:04 davem Exp $
9 *
10 * Based on linux/net/ipv4/ip_output.c
11 *
12 * This program is free software; you can redistribute it and/or
13 * modify it under the terms of the GNU General Public License
14 * as published by the Free Software Foundation; either version
15 * 2 of the License, or (at your option) any later version.
16 *
17 * Changes:
18 * A.N.Kuznetsov : airthmetics in fragmentation.
19 * extension headers are implemented.
20 * route changes now work.
21 * ip6_forward does not confuse sniffers.
22 * etc.
23 *
24 * H. von Brand : Added missing #include <linux/string.h>
25 * Imran Patel : frag id should be in NBO
26 * Kazunori MIYAZAWA @USAGI
27 * : add ip6_append_data and related functions
28 * for datagram xmit
29 */
30
31 #include <linux/errno.h>
32 #include <linux/types.h>
33 #include <linux/string.h>
34 #include <linux/socket.h>
35 #include <linux/net.h>
36 #include <linux/netdevice.h>
37 #include <linux/if_arp.h>
38 #include <linux/in6.h>
39 #include <linux/tcp.h>
40 #include <linux/route.h>
41 #include <linux/module.h>
42
43 #include <linux/netfilter.h>
44 #include <linux/netfilter_ipv6.h>
45
46 #include <net/sock.h>
47 #include <net/snmp.h>
48
49 #include <net/ipv6.h>
50 #include <net/ndisc.h>
51 #include <net/protocol.h>
52 #include <net/ip6_route.h>
53 #include <net/addrconf.h>
54 #include <net/rawv6.h>
55 #include <net/icmp.h>
56 #include <net/xfrm.h>
57 #include <net/checksum.h>
58
59 static int ip6_fragment(struct sk_buff *skb, int (*output)(struct sk_buff *));
60
61 static __inline__ void ipv6_select_ident(struct sk_buff *skb, struct frag_hdr *fhdr)
62 {
63 static u32 ipv6_fragmentation_id = 1;
64 static DEFINE_SPINLOCK(ip6_id_lock);
65
66 spin_lock_bh(&ip6_id_lock);
67 fhdr->identification = htonl(ipv6_fragmentation_id);
68 if (++ipv6_fragmentation_id == 0)
69 ipv6_fragmentation_id = 1;
70 spin_unlock_bh(&ip6_id_lock);
71 }
72
73 static inline int ip6_output_finish(struct sk_buff *skb)
74 {
75 struct dst_entry *dst = skb->dst;
76
77 if (dst->hh)
78 return neigh_hh_output(dst->hh, skb);
79 else if (dst->neighbour)
80 return dst->neighbour->output(skb);
81
82 IP6_INC_STATS_BH(ip6_dst_idev(dst), IPSTATS_MIB_OUTNOROUTES);
83 kfree_skb(skb);
84 return -EINVAL;
85
86 }
87
88 /* dev_loopback_xmit for use with netfilter. */
89 static int ip6_dev_loopback_xmit(struct sk_buff *newskb)
90 {
91 skb_reset_mac_header(newskb);
92 __skb_pull(newskb, skb_network_offset(newskb));
93 newskb->pkt_type = PACKET_LOOPBACK;
94 newskb->ip_summed = CHECKSUM_UNNECESSARY;
95 BUG_TRAP(newskb->dst);
96
97 netif_rx(newskb);
98 return 0;
99 }
100
101
102 static int ip6_output2(struct sk_buff *skb)
103 {
104 struct dst_entry *dst = skb->dst;
105 struct net_device *dev = dst->dev;
106
107 skb->protocol = htons(ETH_P_IPV6);
108 skb->dev = dev;
109
110 if (ipv6_addr_is_multicast(&ipv6_hdr(skb)->daddr)) {
111 struct ipv6_pinfo* np = skb->sk ? inet6_sk(skb->sk) : NULL;
112 struct inet6_dev *idev = ip6_dst_idev(skb->dst);
113
114 if (!(dev->flags & IFF_LOOPBACK) && (!np || np->mc_loop) &&
115 ipv6_chk_mcast_addr(dev, &ipv6_hdr(skb)->daddr,
116 &ipv6_hdr(skb)->saddr)) {
117 struct sk_buff *newskb = skb_clone(skb, GFP_ATOMIC);
118
119 /* Do not check for IFF_ALLMULTI; multicast routing
120 is not supported in any case.
121 */
122 if (newskb)
123 NF_HOOK(PF_INET6, NF_IP6_POST_ROUTING, newskb, NULL,
124 newskb->dev,
125 ip6_dev_loopback_xmit);
126
127 if (ipv6_hdr(skb)->hop_limit == 0) {
128 IP6_INC_STATS(idev, IPSTATS_MIB_OUTDISCARDS);
129 kfree_skb(skb);
130 return 0;
131 }
132 }
133
134 IP6_INC_STATS(idev, IPSTATS_MIB_OUTMCASTPKTS);
135 }
136
137 return NF_HOOK(PF_INET6, NF_IP6_POST_ROUTING, skb,NULL, skb->dev,ip6_output_finish);
138 }
139
140 static inline int ip6_skb_dst_mtu(struct sk_buff *skb)
141 {
142 struct ipv6_pinfo *np = skb->sk ? inet6_sk(skb->sk) : NULL;
143
144 return (np && np->pmtudisc == IPV6_PMTUDISC_PROBE) ?
145 skb->dst->dev->mtu : dst_mtu(skb->dst);
146 }
147
148 int ip6_output(struct sk_buff *skb)
149 {
150 if ((skb->len > ip6_skb_dst_mtu(skb) && !skb_is_gso(skb)) ||
151 dst_allfrag(skb->dst))
152 return ip6_fragment(skb, ip6_output2);
153 else
154 return ip6_output2(skb);
155 }
156
157 /*
158 * xmit an sk_buff (used by TCP)
159 */
160
161 int ip6_xmit(struct sock *sk, struct sk_buff *skb, struct flowi *fl,
162 struct ipv6_txoptions *opt, int ipfragok)
163 {
164 struct ipv6_pinfo *np = inet6_sk(sk);
165 struct in6_addr *first_hop = &fl->fl6_dst;
166 struct dst_entry *dst = skb->dst;
167 struct ipv6hdr *hdr;
168 u8 proto = fl->proto;
169 int seg_len = skb->len;
170 int hlimit, tclass;
171 u32 mtu;
172
173 if (opt) {
174 int head_room;
175
176 /* First: exthdrs may take lots of space (~8K for now)
177 MAX_HEADER is not enough.
178 */
179 head_room = opt->opt_nflen + opt->opt_flen;
180 seg_len += head_room;
181 head_room += sizeof(struct ipv6hdr) + LL_RESERVED_SPACE(dst->dev);
182
183 if (skb_headroom(skb) < head_room) {
184 struct sk_buff *skb2 = skb_realloc_headroom(skb, head_room);
185 if (skb2 == NULL) {
186 IP6_INC_STATS(ip6_dst_idev(skb->dst),
187 IPSTATS_MIB_OUTDISCARDS);
188 kfree_skb(skb);
189 return -ENOBUFS;
190 }
191 kfree_skb(skb);
192 skb = skb2;
193 if (sk)
194 skb_set_owner_w(skb, sk);
195 }
196 if (opt->opt_flen)
197 ipv6_push_frag_opts(skb, opt, &proto);
198 if (opt->opt_nflen)
199 ipv6_push_nfrag_opts(skb, opt, &proto, &first_hop);
200 }
201
202 skb_push(skb, sizeof(struct ipv6hdr));
203 skb_reset_network_header(skb);
204 hdr = ipv6_hdr(skb);
205
206 /*
207 * Fill in the IPv6 header
208 */
209
210 hlimit = -1;
211 if (np)
212 hlimit = np->hop_limit;
213 if (hlimit < 0)
214 hlimit = dst_metric(dst, RTAX_HOPLIMIT);
215 if (hlimit < 0)
216 hlimit = ipv6_get_hoplimit(dst->dev);
217
218 tclass = -1;
219 if (np)
220 tclass = np->tclass;
221 if (tclass < 0)
222 tclass = 0;
223
224 *(__be32 *)hdr = htonl(0x60000000 | (tclass << 20)) | fl->fl6_flowlabel;
225
226 hdr->payload_len = htons(seg_len);
227 hdr->nexthdr = proto;
228 hdr->hop_limit = hlimit;
229
230 ipv6_addr_copy(&hdr->saddr, &fl->fl6_src);
231 ipv6_addr_copy(&hdr->daddr, first_hop);
232
233 skb->priority = sk->sk_priority;
234
235 mtu = dst_mtu(dst);
236 if ((skb->len <= mtu) || ipfragok || skb_is_gso(skb)) {
237 IP6_INC_STATS(ip6_dst_idev(skb->dst),
238 IPSTATS_MIB_OUTREQUESTS);
239 return NF_HOOK(PF_INET6, NF_IP6_LOCAL_OUT, skb, NULL, dst->dev,
240 dst_output);
241 }
242
243 if (net_ratelimit())
244 printk(KERN_DEBUG "IPv6: sending pkt_too_big to self\n");
245 skb->dev = dst->dev;
246 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu, skb->dev);
247 IP6_INC_STATS(ip6_dst_idev(skb->dst), IPSTATS_MIB_FRAGFAILS);
248 kfree_skb(skb);
249 return -EMSGSIZE;
250 }
251
252 EXPORT_SYMBOL(ip6_xmit);
253
254 /*
255 * To avoid extra problems ND packets are send through this
256 * routine. It's code duplication but I really want to avoid
257 * extra checks since ipv6_build_header is used by TCP (which
258 * is for us performance critical)
259 */
260
261 int ip6_nd_hdr(struct sock *sk, struct sk_buff *skb, struct net_device *dev,
262 struct in6_addr *saddr, struct in6_addr *daddr,
263 int proto, int len)
264 {
265 struct ipv6_pinfo *np = inet6_sk(sk);
266 struct ipv6hdr *hdr;
267 int totlen;
268
269 skb->protocol = htons(ETH_P_IPV6);
270 skb->dev = dev;
271
272 totlen = len + sizeof(struct ipv6hdr);
273
274 skb_reset_network_header(skb);
275 skb_put(skb, sizeof(struct ipv6hdr));
276 hdr = ipv6_hdr(skb);
277
278 *(__be32*)hdr = htonl(0x60000000);
279
280 hdr->payload_len = htons(len);
281 hdr->nexthdr = proto;
282 hdr->hop_limit = np->hop_limit;
283
284 ipv6_addr_copy(&hdr->saddr, saddr);
285 ipv6_addr_copy(&hdr->daddr, daddr);
286
287 return 0;
288 }
289
290 static int ip6_call_ra_chain(struct sk_buff *skb, int sel)
291 {
292 struct ip6_ra_chain *ra;
293 struct sock *last = NULL;
294
295 read_lock(&ip6_ra_lock);
296 for (ra = ip6_ra_chain; ra; ra = ra->next) {
297 struct sock *sk = ra->sk;
298 if (sk && ra->sel == sel &&
299 (!sk->sk_bound_dev_if ||
300 sk->sk_bound_dev_if == skb->dev->ifindex)) {
301 if (last) {
302 struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
303 if (skb2)
304 rawv6_rcv(last, skb2);
305 }
306 last = sk;
307 }
308 }
309
310 if (last) {
311 rawv6_rcv(last, skb);
312 read_unlock(&ip6_ra_lock);
313 return 1;
314 }
315 read_unlock(&ip6_ra_lock);
316 return 0;
317 }
318
319 static int ip6_forward_proxy_check(struct sk_buff *skb)
320 {
321 struct ipv6hdr *hdr = ipv6_hdr(skb);
322 u8 nexthdr = hdr->nexthdr;
323 int offset;
324
325 if (ipv6_ext_hdr(nexthdr)) {
326 offset = ipv6_skip_exthdr(skb, sizeof(*hdr), &nexthdr);
327 if (offset < 0)
328 return 0;
329 } else
330 offset = sizeof(struct ipv6hdr);
331
332 if (nexthdr == IPPROTO_ICMPV6) {
333 struct icmp6hdr *icmp6;
334
335 if (!pskb_may_pull(skb, (skb_network_header(skb) +
336 offset + 1 - skb->data)))
337 return 0;
338
339 icmp6 = (struct icmp6hdr *)(skb_network_header(skb) + offset);
340
341 switch (icmp6->icmp6_type) {
342 case NDISC_ROUTER_SOLICITATION:
343 case NDISC_ROUTER_ADVERTISEMENT:
344 case NDISC_NEIGHBOUR_SOLICITATION:
345 case NDISC_NEIGHBOUR_ADVERTISEMENT:
346 case NDISC_REDIRECT:
347 /* For reaction involving unicast neighbor discovery
348 * message destined to the proxied address, pass it to
349 * input function.
350 */
351 return 1;
352 default:
353 break;
354 }
355 }
356
357 /*
358 * The proxying router can't forward traffic sent to a link-local
359 * address, so signal the sender and discard the packet. This
360 * behavior is clarified by the MIPv6 specification.
361 */
362 if (ipv6_addr_type(&hdr->daddr) & IPV6_ADDR_LINKLOCAL) {
363 dst_link_failure(skb);
364 return -1;
365 }
366
367 return 0;
368 }
369
370 static inline int ip6_forward_finish(struct sk_buff *skb)
371 {
372 return dst_output(skb);
373 }
374
375 int ip6_forward(struct sk_buff *skb)
376 {
377 struct dst_entry *dst = skb->dst;
378 struct ipv6hdr *hdr = ipv6_hdr(skb);
379 struct inet6_skb_parm *opt = IP6CB(skb);
380
381 if (ipv6_devconf.forwarding == 0)
382 goto error;
383
384 if (!xfrm6_policy_check(NULL, XFRM_POLICY_FWD, skb)) {
385 IP6_INC_STATS(ip6_dst_idev(dst), IPSTATS_MIB_INDISCARDS);
386 goto drop;
387 }
388
389 skb_forward_csum(skb);
390
391 /*
392 * We DO NOT make any processing on
393 * RA packets, pushing them to user level AS IS
394 * without ane WARRANTY that application will be able
395 * to interpret them. The reason is that we
396 * cannot make anything clever here.
397 *
398 * We are not end-node, so that if packet contains
399 * AH/ESP, we cannot make anything.
400 * Defragmentation also would be mistake, RA packets
401 * cannot be fragmented, because there is no warranty
402 * that different fragments will go along one path. --ANK
403 */
404 if (opt->ra) {
405 u8 *ptr = skb_network_header(skb) + opt->ra;
406 if (ip6_call_ra_chain(skb, (ptr[2]<<8) + ptr[3]))
407 return 0;
408 }
409
410 /*
411 * check and decrement ttl
412 */
413 if (hdr->hop_limit <= 1) {
414 /* Force OUTPUT device used as source address */
415 skb->dev = dst->dev;
416 icmpv6_send(skb, ICMPV6_TIME_EXCEED, ICMPV6_EXC_HOPLIMIT,
417 0, skb->dev);
418 IP6_INC_STATS_BH(ip6_dst_idev(dst), IPSTATS_MIB_INHDRERRORS);
419
420 kfree_skb(skb);
421 return -ETIMEDOUT;
422 }
423
424 /* XXX: idev->cnf.proxy_ndp? */
425 if (ipv6_devconf.proxy_ndp &&
426 pneigh_lookup(&nd_tbl, &hdr->daddr, skb->dev, 0)) {
427 int proxied = ip6_forward_proxy_check(skb);
428 if (proxied > 0)
429 return ip6_input(skb);
430 else if (proxied < 0) {
431 IP6_INC_STATS(ip6_dst_idev(dst), IPSTATS_MIB_INDISCARDS);
432 goto drop;
433 }
434 }
435
436 if (!xfrm6_route_forward(skb)) {
437 IP6_INC_STATS(ip6_dst_idev(dst), IPSTATS_MIB_INDISCARDS);
438 goto drop;
439 }
440 dst = skb->dst;
441
442 /* IPv6 specs say nothing about it, but it is clear that we cannot
443 send redirects to source routed frames.
444 */
445 if (skb->dev == dst->dev && dst->neighbour && opt->srcrt == 0) {
446 struct in6_addr *target = NULL;
447 struct rt6_info *rt;
448 struct neighbour *n = dst->neighbour;
449
450 /*
451 * incoming and outgoing devices are the same
452 * send a redirect.
453 */
454
455 rt = (struct rt6_info *) dst;
456 if ((rt->rt6i_flags & RTF_GATEWAY))
457 target = (struct in6_addr*)&n->primary_key;
458 else
459 target = &hdr->daddr;
460
461 /* Limit redirects both by destination (here)
462 and by source (inside ndisc_send_redirect)
463 */
464 if (xrlim_allow(dst, 1*HZ))
465 ndisc_send_redirect(skb, n, target);
466 } else if (ipv6_addr_type(&hdr->saddr)&(IPV6_ADDR_MULTICAST|IPV6_ADDR_LOOPBACK
467 |IPV6_ADDR_LINKLOCAL)) {
468 /* This check is security critical. */
469 goto error;
470 }
471
472 if (skb->len > dst_mtu(dst)) {
473 /* Again, force OUTPUT device used as source address */
474 skb->dev = dst->dev;
475 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, dst_mtu(dst), skb->dev);
476 IP6_INC_STATS_BH(ip6_dst_idev(dst), IPSTATS_MIB_INTOOBIGERRORS);
477 IP6_INC_STATS_BH(ip6_dst_idev(dst), IPSTATS_MIB_FRAGFAILS);
478 kfree_skb(skb);
479 return -EMSGSIZE;
480 }
481
482 if (skb_cow(skb, dst->dev->hard_header_len)) {
483 IP6_INC_STATS(ip6_dst_idev(dst), IPSTATS_MIB_OUTDISCARDS);
484 goto drop;
485 }
486
487 hdr = ipv6_hdr(skb);
488
489 /* Mangling hops number delayed to point after skb COW */
490
491 hdr->hop_limit--;
492
493 IP6_INC_STATS_BH(ip6_dst_idev(dst), IPSTATS_MIB_OUTFORWDATAGRAMS);
494 return NF_HOOK(PF_INET6,NF_IP6_FORWARD, skb, skb->dev, dst->dev, ip6_forward_finish);
495
496 error:
497 IP6_INC_STATS_BH(ip6_dst_idev(dst), IPSTATS_MIB_INADDRERRORS);
498 drop:
499 kfree_skb(skb);
500 return -EINVAL;
501 }
502
503 static void ip6_copy_metadata(struct sk_buff *to, struct sk_buff *from)
504 {
505 to->pkt_type = from->pkt_type;
506 to->priority = from->priority;
507 to->protocol = from->protocol;
508 dst_release(to->dst);
509 to->dst = dst_clone(from->dst);
510 to->dev = from->dev;
511 to->mark = from->mark;
512
513 #ifdef CONFIG_NET_SCHED
514 to->tc_index = from->tc_index;
515 #endif
516 nf_copy(to, from);
517 skb_copy_secmark(to, from);
518 }
519
520 int ip6_find_1stfragopt(struct sk_buff *skb, u8 **nexthdr)
521 {
522 u16 offset = sizeof(struct ipv6hdr);
523 struct ipv6_opt_hdr *exthdr =
524 (struct ipv6_opt_hdr *)(ipv6_hdr(skb) + 1);
525 unsigned int packet_len = skb->tail - skb->network_header;
526 int found_rhdr = 0;
527 *nexthdr = &ipv6_hdr(skb)->nexthdr;
528
529 while (offset + 1 <= packet_len) {
530
531 switch (**nexthdr) {
532
533 case NEXTHDR_HOP:
534 break;
535 case NEXTHDR_ROUTING:
536 found_rhdr = 1;
537 break;
538 case NEXTHDR_DEST:
539 #ifdef CONFIG_IPV6_MIP6
540 if (ipv6_find_tlv(skb, offset, IPV6_TLV_HAO) >= 0)
541 break;
542 #endif
543 if (found_rhdr)
544 return offset;
545 break;
546 default :
547 return offset;
548 }
549
550 offset += ipv6_optlen(exthdr);
551 *nexthdr = &exthdr->nexthdr;
552 exthdr = (struct ipv6_opt_hdr *)(skb_network_header(skb) +
553 offset);
554 }
555
556 return offset;
557 }
558 EXPORT_SYMBOL_GPL(ip6_find_1stfragopt);
559
560 static int ip6_fragment(struct sk_buff *skb, int (*output)(struct sk_buff *))
561 {
562 struct net_device *dev;
563 struct sk_buff *frag;
564 struct rt6_info *rt = (struct rt6_info*)skb->dst;
565 struct ipv6_pinfo *np = skb->sk ? inet6_sk(skb->sk) : NULL;
566 struct ipv6hdr *tmp_hdr;
567 struct frag_hdr *fh;
568 unsigned int mtu, hlen, left, len;
569 __be32 frag_id = 0;
570 int ptr, offset = 0, err=0;
571 u8 *prevhdr, nexthdr = 0;
572
573 dev = rt->u.dst.dev;
574 hlen = ip6_find_1stfragopt(skb, &prevhdr);
575 nexthdr = *prevhdr;
576
577 mtu = ip6_skb_dst_mtu(skb);
578
579 /* We must not fragment if the socket is set to force MTU discovery
580 * or if the skb it not generated by a local socket. (This last
581 * check should be redundant, but it's free.)
582 */
583 if (!np || np->pmtudisc >= IPV6_PMTUDISC_DO) {
584 skb->dev = skb->dst->dev;
585 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu, skb->dev);
586 IP6_INC_STATS(ip6_dst_idev(skb->dst), IPSTATS_MIB_FRAGFAILS);
587 kfree_skb(skb);
588 return -EMSGSIZE;
589 }
590
591 if (np && np->frag_size < mtu) {
592 if (np->frag_size)
593 mtu = np->frag_size;
594 }
595 mtu -= hlen + sizeof(struct frag_hdr);
596
597 if (skb_shinfo(skb)->frag_list) {
598 int first_len = skb_pagelen(skb);
599
600 if (first_len - hlen > mtu ||
601 ((first_len - hlen) & 7) ||
602 skb_cloned(skb))
603 goto slow_path;
604
605 for (frag = skb_shinfo(skb)->frag_list; frag; frag = frag->next) {
606 /* Correct geometry. */
607 if (frag->len > mtu ||
608 ((frag->len & 7) && frag->next) ||
609 skb_headroom(frag) < hlen)
610 goto slow_path;
611
612 /* Partially cloned skb? */
613 if (skb_shared(frag))
614 goto slow_path;
615
616 BUG_ON(frag->sk);
617 if (skb->sk) {
618 sock_hold(skb->sk);
619 frag->sk = skb->sk;
620 frag->destructor = sock_wfree;
621 skb->truesize -= frag->truesize;
622 }
623 }
624
625 err = 0;
626 offset = 0;
627 frag = skb_shinfo(skb)->frag_list;
628 skb_shinfo(skb)->frag_list = NULL;
629 /* BUILD HEADER */
630
631 *prevhdr = NEXTHDR_FRAGMENT;
632 tmp_hdr = kmemdup(skb_network_header(skb), hlen, GFP_ATOMIC);
633 if (!tmp_hdr) {
634 IP6_INC_STATS(ip6_dst_idev(skb->dst), IPSTATS_MIB_FRAGFAILS);
635 return -ENOMEM;
636 }
637
638 __skb_pull(skb, hlen);
639 fh = (struct frag_hdr*)__skb_push(skb, sizeof(struct frag_hdr));
640 __skb_push(skb, hlen);
641 skb_reset_network_header(skb);
642 memcpy(skb_network_header(skb), tmp_hdr, hlen);
643
644 ipv6_select_ident(skb, fh);
645 fh->nexthdr = nexthdr;
646 fh->reserved = 0;
647 fh->frag_off = htons(IP6_MF);
648 frag_id = fh->identification;
649
650 first_len = skb_pagelen(skb);
651 skb->data_len = first_len - skb_headlen(skb);
652 skb->len = first_len;
653 ipv6_hdr(skb)->payload_len = htons(first_len -
654 sizeof(struct ipv6hdr));
655
656 dst_hold(&rt->u.dst);
657
658 for (;;) {
659 /* Prepare header of the next frame,
660 * before previous one went down. */
661 if (frag) {
662 frag->ip_summed = CHECKSUM_NONE;
663 skb_reset_transport_header(frag);
664 fh = (struct frag_hdr*)__skb_push(frag, sizeof(struct frag_hdr));
665 __skb_push(frag, hlen);
666 skb_reset_network_header(frag);
667 memcpy(skb_network_header(frag), tmp_hdr,
668 hlen);
669 offset += skb->len - hlen - sizeof(struct frag_hdr);
670 fh->nexthdr = nexthdr;
671 fh->reserved = 0;
672 fh->frag_off = htons(offset);
673 if (frag->next != NULL)
674 fh->frag_off |= htons(IP6_MF);
675 fh->identification = frag_id;
676 ipv6_hdr(frag)->payload_len =
677 htons(frag->len -
678 sizeof(struct ipv6hdr));
679 ip6_copy_metadata(frag, skb);
680 }
681
682 err = output(skb);
683 if(!err)
684 IP6_INC_STATS(ip6_dst_idev(&rt->u.dst), IPSTATS_MIB_FRAGCREATES);
685
686 if (err || !frag)
687 break;
688
689 skb = frag;
690 frag = skb->next;
691 skb->next = NULL;
692 }
693
694 kfree(tmp_hdr);
695
696 if (err == 0) {
697 IP6_INC_STATS(ip6_dst_idev(&rt->u.dst), IPSTATS_MIB_FRAGOKS);
698 dst_release(&rt->u.dst);
699 return 0;
700 }
701
702 while (frag) {
703 skb = frag->next;
704 kfree_skb(frag);
705 frag = skb;
706 }
707
708 IP6_INC_STATS(ip6_dst_idev(&rt->u.dst), IPSTATS_MIB_FRAGFAILS);
709 dst_release(&rt->u.dst);
710 return err;
711 }
712
713 slow_path:
714 left = skb->len - hlen; /* Space per frame */
715 ptr = hlen; /* Where to start from */
716
717 /*
718 * Fragment the datagram.
719 */
720
721 *prevhdr = NEXTHDR_FRAGMENT;
722
723 /*
724 * Keep copying data until we run out.
725 */
726 while(left > 0) {
727 len = left;
728 /* IF: it doesn't fit, use 'mtu' - the data space left */
729 if (len > mtu)
730 len = mtu;
731 /* IF: we are not sending upto and including the packet end
732 then align the next start on an eight byte boundary */
733 if (len < left) {
734 len &= ~7;
735 }
736 /*
737 * Allocate buffer.
738 */
739
740 if ((frag = alloc_skb(len+hlen+sizeof(struct frag_hdr)+LL_RESERVED_SPACE(rt->u.dst.dev), GFP_ATOMIC)) == NULL) {
741 NETDEBUG(KERN_INFO "IPv6: frag: no memory for new fragment!\n");
742 IP6_INC_STATS(ip6_dst_idev(skb->dst),
743 IPSTATS_MIB_FRAGFAILS);
744 err = -ENOMEM;
745 goto fail;
746 }
747
748 /*
749 * Set up data on packet
750 */
751
752 ip6_copy_metadata(frag, skb);
753 skb_reserve(frag, LL_RESERVED_SPACE(rt->u.dst.dev));
754 skb_put(frag, len + hlen + sizeof(struct frag_hdr));
755 skb_reset_network_header(frag);
756 fh = (struct frag_hdr *)(skb_network_header(frag) + hlen);
757 frag->transport_header = (frag->network_header + hlen +
758 sizeof(struct frag_hdr));
759
760 /*
761 * Charge the memory for the fragment to any owner
762 * it might possess
763 */
764 if (skb->sk)
765 skb_set_owner_w(frag, skb->sk);
766
767 /*
768 * Copy the packet header into the new buffer.
769 */
770 skb_copy_from_linear_data(skb, skb_network_header(frag), hlen);
771
772 /*
773 * Build fragment header.
774 */
775 fh->nexthdr = nexthdr;
776 fh->reserved = 0;
777 if (!frag_id) {
778 ipv6_select_ident(skb, fh);
779 frag_id = fh->identification;
780 } else
781 fh->identification = frag_id;
782
783 /*
784 * Copy a block of the IP datagram.
785 */
786 if (skb_copy_bits(skb, ptr, skb_transport_header(skb), len))
787 BUG();
788 left -= len;
789
790 fh->frag_off = htons(offset);
791 if (left > 0)
792 fh->frag_off |= htons(IP6_MF);
793 ipv6_hdr(frag)->payload_len = htons(frag->len -
794 sizeof(struct ipv6hdr));
795
796 ptr += len;
797 offset += len;
798
799 /*
800 * Put this fragment into the sending queue.
801 */
802 err = output(frag);
803 if (err)
804 goto fail;
805
806 IP6_INC_STATS(ip6_dst_idev(skb->dst), IPSTATS_MIB_FRAGCREATES);
807 }
808 IP6_INC_STATS(ip6_dst_idev(skb->dst),
809 IPSTATS_MIB_FRAGOKS);
810 kfree_skb(skb);
811 return err;
812
813 fail:
814 IP6_INC_STATS(ip6_dst_idev(skb->dst),
815 IPSTATS_MIB_FRAGFAILS);
816 kfree_skb(skb);
817 return err;
818 }
819
820 static inline int ip6_rt_check(struct rt6key *rt_key,
821 struct in6_addr *fl_addr,
822 struct in6_addr *addr_cache)
823 {
824 return ((rt_key->plen != 128 || !ipv6_addr_equal(fl_addr, &rt_key->addr)) &&
825 (addr_cache == NULL || !ipv6_addr_equal(fl_addr, addr_cache)));
826 }
827
828 static struct dst_entry *ip6_sk_dst_check(struct sock *sk,
829 struct dst_entry *dst,
830 struct flowi *fl)
831 {
832 struct ipv6_pinfo *np = inet6_sk(sk);
833 struct rt6_info *rt = (struct rt6_info *)dst;
834
835 if (!dst)
836 goto out;
837
838 /* Yes, checking route validity in not connected
839 * case is not very simple. Take into account,
840 * that we do not support routing by source, TOS,
841 * and MSG_DONTROUTE --ANK (980726)
842 *
843 * 1. ip6_rt_check(): If route was host route,
844 * check that cached destination is current.
845 * If it is network route, we still may
846 * check its validity using saved pointer
847 * to the last used address: daddr_cache.
848 * We do not want to save whole address now,
849 * (because main consumer of this service
850 * is tcp, which has not this problem),
851 * so that the last trick works only on connected
852 * sockets.
853 * 2. oif also should be the same.
854 */
855 if (ip6_rt_check(&rt->rt6i_dst, &fl->fl6_dst, np->daddr_cache) ||
856 #ifdef CONFIG_IPV6_SUBTREES
857 ip6_rt_check(&rt->rt6i_src, &fl->fl6_src, np->saddr_cache) ||
858 #endif
859 (fl->oif && fl->oif != dst->dev->ifindex)) {
860 dst_release(dst);
861 dst = NULL;
862 }
863
864 out:
865 return dst;
866 }
867
868 static int ip6_dst_lookup_tail(struct sock *sk,
869 struct dst_entry **dst, struct flowi *fl)
870 {
871 int err;
872
873 if (*dst == NULL)
874 *dst = ip6_route_output(sk, fl);
875
876 if ((err = (*dst)->error))
877 goto out_err_release;
878
879 if (ipv6_addr_any(&fl->fl6_src)) {
880 err = ipv6_get_saddr(*dst, &fl->fl6_dst, &fl->fl6_src);
881 if (err)
882 goto out_err_release;
883 }
884
885 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
886 /*
887 * Here if the dst entry we've looked up
888 * has a neighbour entry that is in the INCOMPLETE
889 * state and the src address from the flow is
890 * marked as OPTIMISTIC, we release the found
891 * dst entry and replace it instead with the
892 * dst entry of the nexthop router
893 */
894 if (!((*dst)->neighbour->nud_state & NUD_VALID)) {
895 struct inet6_ifaddr *ifp;
896 struct flowi fl_gw;
897 int redirect;
898
899 ifp = ipv6_get_ifaddr(&fl->fl6_src, (*dst)->dev, 1);
900
901 redirect = (ifp && ifp->flags & IFA_F_OPTIMISTIC);
902 if (ifp)
903 in6_ifa_put(ifp);
904
905 if (redirect) {
906 /*
907 * We need to get the dst entry for the
908 * default router instead
909 */
910 dst_release(*dst);
911 memcpy(&fl_gw, fl, sizeof(struct flowi));
912 memset(&fl_gw.fl6_dst, 0, sizeof(struct in6_addr));
913 *dst = ip6_route_output(sk, &fl_gw);
914 if ((err = (*dst)->error))
915 goto out_err_release;
916 }
917 }
918 #endif
919
920 return 0;
921
922 out_err_release:
923 dst_release(*dst);
924 *dst = NULL;
925 return err;
926 }
927
928 /**
929 * ip6_dst_lookup - perform route lookup on flow
930 * @sk: socket which provides route info
931 * @dst: pointer to dst_entry * for result
932 * @fl: flow to lookup
933 *
934 * This function performs a route lookup on the given flow.
935 *
936 * It returns zero on success, or a standard errno code on error.
937 */
938 int ip6_dst_lookup(struct sock *sk, struct dst_entry **dst, struct flowi *fl)
939 {
940 *dst = NULL;
941 return ip6_dst_lookup_tail(sk, dst, fl);
942 }
943 EXPORT_SYMBOL_GPL(ip6_dst_lookup);
944
945 /**
946 * ip6_sk_dst_lookup - perform socket cached route lookup on flow
947 * @sk: socket which provides the dst cache and route info
948 * @dst: pointer to dst_entry * for result
949 * @fl: flow to lookup
950 *
951 * This function performs a route lookup on the given flow with the
952 * possibility of using the cached route in the socket if it is valid.
953 * It will take the socket dst lock when operating on the dst cache.
954 * As a result, this function can only be used in process context.
955 *
956 * It returns zero on success, or a standard errno code on error.
957 */
958 int ip6_sk_dst_lookup(struct sock *sk, struct dst_entry **dst, struct flowi *fl)
959 {
960 *dst = NULL;
961 if (sk) {
962 *dst = sk_dst_check(sk, inet6_sk(sk)->dst_cookie);
963 *dst = ip6_sk_dst_check(sk, *dst, fl);
964 }
965
966 return ip6_dst_lookup_tail(sk, dst, fl);
967 }
968 EXPORT_SYMBOL_GPL(ip6_sk_dst_lookup);
969
970 static inline int ip6_ufo_append_data(struct sock *sk,
971 int getfrag(void *from, char *to, int offset, int len,
972 int odd, struct sk_buff *skb),
973 void *from, int length, int hh_len, int fragheaderlen,
974 int transhdrlen, int mtu,unsigned int flags)
975
976 {
977 struct sk_buff *skb;
978 int err;
979
980 /* There is support for UDP large send offload by network
981 * device, so create one single skb packet containing complete
982 * udp datagram
983 */
984 if ((skb = skb_peek_tail(&sk->sk_write_queue)) == NULL) {
985 skb = sock_alloc_send_skb(sk,
986 hh_len + fragheaderlen + transhdrlen + 20,
987 (flags & MSG_DONTWAIT), &err);
988 if (skb == NULL)
989 return -ENOMEM;
990
991 /* reserve space for Hardware header */
992 skb_reserve(skb, hh_len);
993
994 /* create space for UDP/IP header */
995 skb_put(skb,fragheaderlen + transhdrlen);
996
997 /* initialize network header pointer */
998 skb_reset_network_header(skb);
999
1000 /* initialize protocol header pointer */
1001 skb->transport_header = skb->network_header + fragheaderlen;
1002
1003 skb->ip_summed = CHECKSUM_PARTIAL;
1004 skb->csum = 0;
1005 sk->sk_sndmsg_off = 0;
1006 }
1007
1008 err = skb_append_datato_frags(sk,skb, getfrag, from,
1009 (length - transhdrlen));
1010 if (!err) {
1011 struct frag_hdr fhdr;
1012
1013 /* specify the length of each IP datagram fragment*/
1014 skb_shinfo(skb)->gso_size = mtu - fragheaderlen -
1015 sizeof(struct frag_hdr);
1016 skb_shinfo(skb)->gso_type = SKB_GSO_UDP;
1017 ipv6_select_ident(skb, &fhdr);
1018 skb_shinfo(skb)->ip6_frag_id = fhdr.identification;
1019 __skb_queue_tail(&sk->sk_write_queue, skb);
1020
1021 return 0;
1022 }
1023 /* There is not enough support do UPD LSO,
1024 * so follow normal path
1025 */
1026 kfree_skb(skb);
1027
1028 return err;
1029 }
1030
1031 int ip6_append_data(struct sock *sk, int getfrag(void *from, char *to,
1032 int offset, int len, int odd, struct sk_buff *skb),
1033 void *from, int length, int transhdrlen,
1034 int hlimit, int tclass, struct ipv6_txoptions *opt, struct flowi *fl,
1035 struct rt6_info *rt, unsigned int flags)
1036 {
1037 struct inet_sock *inet = inet_sk(sk);
1038 struct ipv6_pinfo *np = inet6_sk(sk);
1039 struct sk_buff *skb;
1040 unsigned int maxfraglen, fragheaderlen;
1041 int exthdrlen;
1042 int hh_len;
1043 int mtu;
1044 int copy;
1045 int err;
1046 int offset = 0;
1047 int csummode = CHECKSUM_NONE;
1048
1049 if (flags&MSG_PROBE)
1050 return 0;
1051 if (skb_queue_empty(&sk->sk_write_queue)) {
1052 /*
1053 * setup for corking
1054 */
1055 if (opt) {
1056 if (np->cork.opt == NULL) {
1057 np->cork.opt = kmalloc(opt->tot_len,
1058 sk->sk_allocation);
1059 if (unlikely(np->cork.opt == NULL))
1060 return -ENOBUFS;
1061 } else if (np->cork.opt->tot_len < opt->tot_len) {
1062 printk(KERN_DEBUG "ip6_append_data: invalid option length\n");
1063 return -EINVAL;
1064 }
1065 memcpy(np->cork.opt, opt, opt->tot_len);
1066 inet->cork.flags |= IPCORK_OPT;
1067 /* need source address above miyazawa*/
1068 }
1069 dst_hold(&rt->u.dst);
1070 np->cork.rt = rt;
1071 inet->cork.fl = *fl;
1072 np->cork.hop_limit = hlimit;
1073 np->cork.tclass = tclass;
1074 mtu = np->pmtudisc == IPV6_PMTUDISC_PROBE ?
1075 rt->u.dst.dev->mtu : dst_mtu(rt->u.dst.path);
1076 if (np->frag_size < mtu) {
1077 if (np->frag_size)
1078 mtu = np->frag_size;
1079 }
1080 inet->cork.fragsize = mtu;
1081 if (dst_allfrag(rt->u.dst.path))
1082 inet->cork.flags |= IPCORK_ALLFRAG;
1083 inet->cork.length = 0;
1084 sk->sk_sndmsg_page = NULL;
1085 sk->sk_sndmsg_off = 0;
1086 exthdrlen = rt->u.dst.header_len + (opt ? opt->opt_flen : 0);
1087 length += exthdrlen;
1088 transhdrlen += exthdrlen;
1089 } else {
1090 rt = np->cork.rt;
1091 fl = &inet->cork.fl;
1092 if (inet->cork.flags & IPCORK_OPT)
1093 opt = np->cork.opt;
1094 transhdrlen = 0;
1095 exthdrlen = 0;
1096 mtu = inet->cork.fragsize;
1097 }
1098
1099 hh_len = LL_RESERVED_SPACE(rt->u.dst.dev);
1100
1101 fragheaderlen = sizeof(struct ipv6hdr) + rt->u.dst.nfheader_len + (opt ? opt->opt_nflen : 0);
1102 maxfraglen = ((mtu - fragheaderlen) & ~7) + fragheaderlen - sizeof(struct frag_hdr);
1103
1104 if (mtu <= sizeof(struct ipv6hdr) + IPV6_MAXPLEN) {
1105 if (inet->cork.length + length > sizeof(struct ipv6hdr) + IPV6_MAXPLEN - fragheaderlen) {
1106 ipv6_local_error(sk, EMSGSIZE, fl, mtu-exthdrlen);
1107 return -EMSGSIZE;
1108 }
1109 }
1110
1111 /*
1112 * Let's try using as much space as possible.
1113 * Use MTU if total length of the message fits into the MTU.
1114 * Otherwise, we need to reserve fragment header and
1115 * fragment alignment (= 8-15 octects, in total).
1116 *
1117 * Note that we may need to "move" the data from the tail of
1118 * of the buffer to the new fragment when we split
1119 * the message.
1120 *
1121 * FIXME: It may be fragmented into multiple chunks
1122 * at once if non-fragmentable extension headers
1123 * are too large.
1124 * --yoshfuji
1125 */
1126
1127 inet->cork.length += length;
1128 if (((length > mtu) && (sk->sk_protocol == IPPROTO_UDP)) &&
1129 (rt->u.dst.dev->features & NETIF_F_UFO)) {
1130
1131 err = ip6_ufo_append_data(sk, getfrag, from, length, hh_len,
1132 fragheaderlen, transhdrlen, mtu,
1133 flags);
1134 if (err)
1135 goto error;
1136 return 0;
1137 }
1138
1139 if ((skb = skb_peek_tail(&sk->sk_write_queue)) == NULL)
1140 goto alloc_new_skb;
1141
1142 while (length > 0) {
1143 /* Check if the remaining data fits into current packet. */
1144 copy = (inet->cork.length <= mtu && !(inet->cork.flags & IPCORK_ALLFRAG) ? mtu : maxfraglen) - skb->len;
1145 if (copy < length)
1146 copy = maxfraglen - skb->len;
1147
1148 if (copy <= 0) {
1149 char *data;
1150 unsigned int datalen;
1151 unsigned int fraglen;
1152 unsigned int fraggap;
1153 unsigned int alloclen;
1154 struct sk_buff *skb_prev;
1155 alloc_new_skb:
1156 skb_prev = skb;
1157
1158 /* There's no room in the current skb */
1159 if (skb_prev)
1160 fraggap = skb_prev->len - maxfraglen;
1161 else
1162 fraggap = 0;
1163
1164 /*
1165 * If remaining data exceeds the mtu,
1166 * we know we need more fragment(s).
1167 */
1168 datalen = length + fraggap;
1169 if (datalen > (inet->cork.length <= mtu && !(inet->cork.flags & IPCORK_ALLFRAG) ? mtu : maxfraglen) - fragheaderlen)
1170 datalen = maxfraglen - fragheaderlen;
1171
1172 fraglen = datalen + fragheaderlen;
1173 if ((flags & MSG_MORE) &&
1174 !(rt->u.dst.dev->features&NETIF_F_SG))
1175 alloclen = mtu;
1176 else
1177 alloclen = datalen + fragheaderlen;
1178
1179 /*
1180 * The last fragment gets additional space at tail.
1181 * Note: we overallocate on fragments with MSG_MODE
1182 * because we have no idea if we're the last one.
1183 */
1184 if (datalen == length + fraggap)
1185 alloclen += rt->u.dst.trailer_len;
1186
1187 /*
1188 * We just reserve space for fragment header.
1189 * Note: this may be overallocation if the message
1190 * (without MSG_MORE) fits into the MTU.
1191 */
1192 alloclen += sizeof(struct frag_hdr);
1193
1194 if (transhdrlen) {
1195 skb = sock_alloc_send_skb(sk,
1196 alloclen + hh_len,
1197 (flags & MSG_DONTWAIT), &err);
1198 } else {
1199 skb = NULL;
1200 if (atomic_read(&sk->sk_wmem_alloc) <=
1201 2 * sk->sk_sndbuf)
1202 skb = sock_wmalloc(sk,
1203 alloclen + hh_len, 1,
1204 sk->sk_allocation);
1205 if (unlikely(skb == NULL))
1206 err = -ENOBUFS;
1207 }
1208 if (skb == NULL)
1209 goto error;
1210 /*
1211 * Fill in the control structures
1212 */
1213 skb->ip_summed = csummode;
1214 skb->csum = 0;
1215 /* reserve for fragmentation */
1216 skb_reserve(skb, hh_len+sizeof(struct frag_hdr));
1217
1218 /*
1219 * Find where to start putting bytes
1220 */
1221 data = skb_put(skb, fraglen);
1222 skb_set_network_header(skb, exthdrlen);
1223 data += fragheaderlen;
1224 skb->transport_header = (skb->network_header +
1225 fragheaderlen);
1226 if (fraggap) {
1227 skb->csum = skb_copy_and_csum_bits(
1228 skb_prev, maxfraglen,
1229 data + transhdrlen, fraggap, 0);
1230 skb_prev->csum = csum_sub(skb_prev->csum,
1231 skb->csum);
1232 data += fraggap;
1233 pskb_trim_unique(skb_prev, maxfraglen);
1234 }
1235 copy = datalen - transhdrlen - fraggap;
1236 if (copy < 0) {
1237 err = -EINVAL;
1238 kfree_skb(skb);
1239 goto error;
1240 } else if (copy > 0 && getfrag(from, data + transhdrlen, offset, copy, fraggap, skb) < 0) {
1241 err = -EFAULT;
1242 kfree_skb(skb);
1243 goto error;
1244 }
1245
1246 offset += copy;
1247 length -= datalen - fraggap;
1248 transhdrlen = 0;
1249 exthdrlen = 0;
1250 csummode = CHECKSUM_NONE;
1251
1252 /*
1253 * Put the packet on the pending queue
1254 */
1255 __skb_queue_tail(&sk->sk_write_queue, skb);
1256 continue;
1257 }
1258
1259 if (copy > length)
1260 copy = length;
1261
1262 if (!(rt->u.dst.dev->features&NETIF_F_SG)) {
1263 unsigned int off;
1264
1265 off = skb->len;
1266 if (getfrag(from, skb_put(skb, copy),
1267 offset, copy, off, skb) < 0) {
1268 __skb_trim(skb, off);
1269 err = -EFAULT;
1270 goto error;
1271 }
1272 } else {
1273 int i = skb_shinfo(skb)->nr_frags;
1274 skb_frag_t *frag = &skb_shinfo(skb)->frags[i-1];
1275 struct page *page = sk->sk_sndmsg_page;
1276 int off = sk->sk_sndmsg_off;
1277 unsigned int left;
1278
1279 if (page && (left = PAGE_SIZE - off) > 0) {
1280 if (copy >= left)
1281 copy = left;
1282 if (page != frag->page) {
1283 if (i == MAX_SKB_FRAGS) {
1284 err = -EMSGSIZE;
1285 goto error;
1286 }
1287 get_page(page);
1288 skb_fill_page_desc(skb, i, page, sk->sk_sndmsg_off, 0);
1289 frag = &skb_shinfo(skb)->frags[i];
1290 }
1291 } else if(i < MAX_SKB_FRAGS) {
1292 if (copy > PAGE_SIZE)
1293 copy = PAGE_SIZE;
1294 page = alloc_pages(sk->sk_allocation, 0);
1295 if (page == NULL) {
1296 err = -ENOMEM;
1297 goto error;
1298 }
1299 sk->sk_sndmsg_page = page;
1300 sk->sk_sndmsg_off = 0;
1301
1302 skb_fill_page_desc(skb, i, page, 0, 0);
1303 frag = &skb_shinfo(skb)->frags[i];
1304 skb->truesize += PAGE_SIZE;
1305 atomic_add(PAGE_SIZE, &sk->sk_wmem_alloc);
1306 } else {
1307 err = -EMSGSIZE;
1308 goto error;
1309 }
1310 if (getfrag(from, page_address(frag->page)+frag->page_offset+frag->size, offset, copy, skb->len, skb) < 0) {
1311 err = -EFAULT;
1312 goto error;
1313 }
1314 sk->sk_sndmsg_off += copy;
1315 frag->size += copy;
1316 skb->len += copy;
1317 skb->data_len += copy;
1318 }
1319 offset += copy;
1320 length -= copy;
1321 }
1322 return 0;
1323 error:
1324 inet->cork.length -= length;
1325 IP6_INC_STATS(rt->rt6i_idev, IPSTATS_MIB_OUTDISCARDS);
1326 return err;
1327 }
1328
1329 int ip6_push_pending_frames(struct sock *sk)
1330 {
1331 struct sk_buff *skb, *tmp_skb;
1332 struct sk_buff **tail_skb;
1333 struct in6_addr final_dst_buf, *final_dst = &final_dst_buf;
1334 struct inet_sock *inet = inet_sk(sk);
1335 struct ipv6_pinfo *np = inet6_sk(sk);
1336 struct ipv6hdr *hdr;
1337 struct ipv6_txoptions *opt = np->cork.opt;
1338 struct rt6_info *rt = np->cork.rt;
1339 struct flowi *fl = &inet->cork.fl;
1340 unsigned char proto = fl->proto;
1341 int err = 0;
1342
1343 if ((skb = __skb_dequeue(&sk->sk_write_queue)) == NULL)
1344 goto out;
1345 tail_skb = &(skb_shinfo(skb)->frag_list);
1346
1347 /* move skb->data to ip header from ext header */
1348 if (skb->data < skb_network_header(skb))
1349 __skb_pull(skb, skb_network_offset(skb));
1350 while ((tmp_skb = __skb_dequeue(&sk->sk_write_queue)) != NULL) {
1351 __skb_pull(tmp_skb, skb_network_header_len(skb));
1352 *tail_skb = tmp_skb;
1353 tail_skb = &(tmp_skb->next);
1354 skb->len += tmp_skb->len;
1355 skb->data_len += tmp_skb->len;
1356 skb->truesize += tmp_skb->truesize;
1357 __sock_put(tmp_skb->sk);
1358 tmp_skb->destructor = NULL;
1359 tmp_skb->sk = NULL;
1360 }
1361
1362 ipv6_addr_copy(final_dst, &fl->fl6_dst);
1363 __skb_pull(skb, skb_network_header_len(skb));
1364 if (opt && opt->opt_flen)
1365 ipv6_push_frag_opts(skb, opt, &proto);
1366 if (opt && opt->opt_nflen)
1367 ipv6_push_nfrag_opts(skb, opt, &proto, &final_dst);
1368
1369 skb_push(skb, sizeof(struct ipv6hdr));
1370 skb_reset_network_header(skb);
1371 hdr = ipv6_hdr(skb);
1372
1373 *(__be32*)hdr = fl->fl6_flowlabel |
1374 htonl(0x60000000 | ((int)np->cork.tclass << 20));
1375
1376 if (skb->len <= sizeof(struct ipv6hdr) + IPV6_MAXPLEN)
1377 hdr->payload_len = htons(skb->len - sizeof(struct ipv6hdr));
1378 else
1379 hdr->payload_len = 0;
1380 hdr->hop_limit = np->cork.hop_limit;
1381 hdr->nexthdr = proto;
1382 ipv6_addr_copy(&hdr->saddr, &fl->fl6_src);
1383 ipv6_addr_copy(&hdr->daddr, final_dst);
1384
1385 skb->priority = sk->sk_priority;
1386
1387 skb->dst = dst_clone(&rt->u.dst);
1388 IP6_INC_STATS(rt->rt6i_idev, IPSTATS_MIB_OUTREQUESTS);
1389 err = NF_HOOK(PF_INET6, NF_IP6_LOCAL_OUT, skb, NULL, skb->dst->dev, dst_output);
1390 if (err) {
1391 if (err > 0)
1392 err = np->recverr ? net_xmit_errno(err) : 0;
1393 if (err)
1394 goto error;
1395 }
1396
1397 out:
1398 inet->cork.flags &= ~IPCORK_OPT;
1399 kfree(np->cork.opt);
1400 np->cork.opt = NULL;
1401 if (np->cork.rt) {
1402 dst_release(&np->cork.rt->u.dst);
1403 np->cork.rt = NULL;
1404 inet->cork.flags &= ~IPCORK_ALLFRAG;
1405 }
1406 memset(&inet->cork.fl, 0, sizeof(inet->cork.fl));
1407 return err;
1408 error:
1409 goto out;
1410 }
1411
1412 void ip6_flush_pending_frames(struct sock *sk)
1413 {
1414 struct inet_sock *inet = inet_sk(sk);
1415 struct ipv6_pinfo *np = inet6_sk(sk);
1416 struct sk_buff *skb;
1417
1418 while ((skb = __skb_dequeue_tail(&sk->sk_write_queue)) != NULL) {
1419 IP6_INC_STATS(ip6_dst_idev(skb->dst),
1420 IPSTATS_MIB_OUTDISCARDS);
1421 kfree_skb(skb);
1422 }
1423
1424 inet->cork.flags &= ~IPCORK_OPT;
1425
1426 kfree(np->cork.opt);
1427 np->cork.opt = NULL;
1428 if (np->cork.rt) {
1429 dst_release(&np->cork.rt->u.dst);
1430 np->cork.rt = NULL;
1431 inet->cork.flags &= ~IPCORK_ALLFRAG;
1432 }
1433 memset(&inet->cork.fl, 0, sizeof(inet->cork.fl));
1434 }
Linux with added FPC-III support