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Merge master.kernel.org:/pub/scm/linux/kernel/git/gregkh/uio-2.6
[usb.git] / net / ipv6 / ip6_output.c
blob50d86e94d9ed3358bf8bad71ca36599adea63527
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 {
467 int addrtype = ipv6_addr_type(&hdr->saddr);
468
469 /* This check is security critical. */
470 if (addrtype & (IPV6_ADDR_MULTICAST|IPV6_ADDR_LOOPBACK))
471 goto error;
472 if (addrtype & IPV6_ADDR_LINKLOCAL) {
473 icmpv6_send(skb, ICMPV6_DEST_UNREACH,
474 ICMPV6_NOT_NEIGHBOUR, 0, skb->dev);
475 goto error;
476 }
477 }
478
479 if (skb->len > dst_mtu(dst)) {
480 /* Again, force OUTPUT device used as source address */
481 skb->dev = dst->dev;
482 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, dst_mtu(dst), skb->dev);
483 IP6_INC_STATS_BH(ip6_dst_idev(dst), IPSTATS_MIB_INTOOBIGERRORS);
484 IP6_INC_STATS_BH(ip6_dst_idev(dst), IPSTATS_MIB_FRAGFAILS);
485 kfree_skb(skb);
486 return -EMSGSIZE;
487 }
488
489 if (skb_cow(skb, dst->dev->hard_header_len)) {
490 IP6_INC_STATS(ip6_dst_idev(dst), IPSTATS_MIB_OUTDISCARDS);
491 goto drop;
492 }
493
494 hdr = ipv6_hdr(skb);
495
496 /* Mangling hops number delayed to point after skb COW */
497
498 hdr->hop_limit--;
499
500 IP6_INC_STATS_BH(ip6_dst_idev(dst), IPSTATS_MIB_OUTFORWDATAGRAMS);
501 return NF_HOOK(PF_INET6,NF_IP6_FORWARD, skb, skb->dev, dst->dev, ip6_forward_finish);
502
503 error:
504 IP6_INC_STATS_BH(ip6_dst_idev(dst), IPSTATS_MIB_INADDRERRORS);
505 drop:
506 kfree_skb(skb);
507 return -EINVAL;
508 }
509
510 static void ip6_copy_metadata(struct sk_buff *to, struct sk_buff *from)
511 {
512 to->pkt_type = from->pkt_type;
513 to->priority = from->priority;
514 to->protocol = from->protocol;
515 dst_release(to->dst);
516 to->dst = dst_clone(from->dst);
517 to->dev = from->dev;
518 to->mark = from->mark;
519
520 #ifdef CONFIG_NET_SCHED
521 to->tc_index = from->tc_index;
522 #endif
523 nf_copy(to, from);
524 #if defined(CONFIG_NETFILTER_XT_TARGET_TRACE) || \
525 defined(CONFIG_NETFILTER_XT_TARGET_TRACE_MODULE)
526 to->nf_trace = from->nf_trace;
527 #endif
528 skb_copy_secmark(to, from);
529 }
530
531 int ip6_find_1stfragopt(struct sk_buff *skb, u8 **nexthdr)
532 {
533 u16 offset = sizeof(struct ipv6hdr);
534 struct ipv6_opt_hdr *exthdr =
535 (struct ipv6_opt_hdr *)(ipv6_hdr(skb) + 1);
536 unsigned int packet_len = skb->tail - skb->network_header;
537 int found_rhdr = 0;
538 *nexthdr = &ipv6_hdr(skb)->nexthdr;
539
540 while (offset + 1 <= packet_len) {
541
542 switch (**nexthdr) {
543
544 case NEXTHDR_HOP:
545 break;
546 case NEXTHDR_ROUTING:
547 found_rhdr = 1;
548 break;
549 case NEXTHDR_DEST:
550 #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
551 if (ipv6_find_tlv(skb, offset, IPV6_TLV_HAO) >= 0)
552 break;
553 #endif
554 if (found_rhdr)
555 return offset;
556 break;
557 default :
558 return offset;
559 }
560
561 offset += ipv6_optlen(exthdr);
562 *nexthdr = &exthdr->nexthdr;
563 exthdr = (struct ipv6_opt_hdr *)(skb_network_header(skb) +
564 offset);
565 }
566
567 return offset;
568 }
569 EXPORT_SYMBOL_GPL(ip6_find_1stfragopt);
570
571 static int ip6_fragment(struct sk_buff *skb, int (*output)(struct sk_buff *))
572 {
573 struct net_device *dev;
574 struct sk_buff *frag;
575 struct rt6_info *rt = (struct rt6_info*)skb->dst;
576 struct ipv6_pinfo *np = skb->sk ? inet6_sk(skb->sk) : NULL;
577 struct ipv6hdr *tmp_hdr;
578 struct frag_hdr *fh;
579 unsigned int mtu, hlen, left, len;
580 __be32 frag_id = 0;
581 int ptr, offset = 0, err=0;
582 u8 *prevhdr, nexthdr = 0;
583
584 dev = rt->u.dst.dev;
585 hlen = ip6_find_1stfragopt(skb, &prevhdr);
586 nexthdr = *prevhdr;
587
588 mtu = ip6_skb_dst_mtu(skb);
589
590 /* We must not fragment if the socket is set to force MTU discovery
591 * or if the skb it not generated by a local socket. (This last
592 * check should be redundant, but it's free.)
593 */
594 if (!np || np->pmtudisc >= IPV6_PMTUDISC_DO) {
595 skb->dev = skb->dst->dev;
596 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu, skb->dev);
597 IP6_INC_STATS(ip6_dst_idev(skb->dst), IPSTATS_MIB_FRAGFAILS);
598 kfree_skb(skb);
599 return -EMSGSIZE;
600 }
601
602 if (np && np->frag_size < mtu) {
603 if (np->frag_size)
604 mtu = np->frag_size;
605 }
606 mtu -= hlen + sizeof(struct frag_hdr);
607
608 if (skb_shinfo(skb)->frag_list) {
609 int first_len = skb_pagelen(skb);
610
611 if (first_len - hlen > mtu ||
612 ((first_len - hlen) & 7) ||
613 skb_cloned(skb))
614 goto slow_path;
615
616 for (frag = skb_shinfo(skb)->frag_list; frag; frag = frag->next) {
617 /* Correct geometry. */
618 if (frag->len > mtu ||
619 ((frag->len & 7) && frag->next) ||
620 skb_headroom(frag) < hlen)
621 goto slow_path;
622
623 /* Partially cloned skb? */
624 if (skb_shared(frag))
625 goto slow_path;
626
627 BUG_ON(frag->sk);
628 if (skb->sk) {
629 sock_hold(skb->sk);
630 frag->sk = skb->sk;
631 frag->destructor = sock_wfree;
632 skb->truesize -= frag->truesize;
633 }
634 }
635
636 err = 0;
637 offset = 0;
638 frag = skb_shinfo(skb)->frag_list;
639 skb_shinfo(skb)->frag_list = NULL;
640 /* BUILD HEADER */
641
642 *prevhdr = NEXTHDR_FRAGMENT;
643 tmp_hdr = kmemdup(skb_network_header(skb), hlen, GFP_ATOMIC);
644 if (!tmp_hdr) {
645 IP6_INC_STATS(ip6_dst_idev(skb->dst), IPSTATS_MIB_FRAGFAILS);
646 return -ENOMEM;
647 }
648
649 __skb_pull(skb, hlen);
650 fh = (struct frag_hdr*)__skb_push(skb, sizeof(struct frag_hdr));
651 __skb_push(skb, hlen);
652 skb_reset_network_header(skb);
653 memcpy(skb_network_header(skb), tmp_hdr, hlen);
654
655 ipv6_select_ident(skb, fh);
656 fh->nexthdr = nexthdr;
657 fh->reserved = 0;
658 fh->frag_off = htons(IP6_MF);
659 frag_id = fh->identification;
660
661 first_len = skb_pagelen(skb);
662 skb->data_len = first_len - skb_headlen(skb);
663 skb->len = first_len;
664 ipv6_hdr(skb)->payload_len = htons(first_len -
665 sizeof(struct ipv6hdr));
666
667 dst_hold(&rt->u.dst);
668
669 for (;;) {
670 /* Prepare header of the next frame,
671 * before previous one went down. */
672 if (frag) {
673 frag->ip_summed = CHECKSUM_NONE;
674 skb_reset_transport_header(frag);
675 fh = (struct frag_hdr*)__skb_push(frag, sizeof(struct frag_hdr));
676 __skb_push(frag, hlen);
677 skb_reset_network_header(frag);
678 memcpy(skb_network_header(frag), tmp_hdr,
679 hlen);
680 offset += skb->len - hlen - sizeof(struct frag_hdr);
681 fh->nexthdr = nexthdr;
682 fh->reserved = 0;
683 fh->frag_off = htons(offset);
684 if (frag->next != NULL)
685 fh->frag_off |= htons(IP6_MF);
686 fh->identification = frag_id;
687 ipv6_hdr(frag)->payload_len =
688 htons(frag->len -
689 sizeof(struct ipv6hdr));
690 ip6_copy_metadata(frag, skb);
691 }
692
693 err = output(skb);
694 if(!err)
695 IP6_INC_STATS(ip6_dst_idev(&rt->u.dst), IPSTATS_MIB_FRAGCREATES);
696
697 if (err || !frag)
698 break;
699
700 skb = frag;
701 frag = skb->next;
702 skb->next = NULL;
703 }
704
705 kfree(tmp_hdr);
706
707 if (err == 0) {
708 IP6_INC_STATS(ip6_dst_idev(&rt->u.dst), IPSTATS_MIB_FRAGOKS);
709 dst_release(&rt->u.dst);
710 return 0;
711 }
712
713 while (frag) {
714 skb = frag->next;
715 kfree_skb(frag);
716 frag = skb;
717 }
718
719 IP6_INC_STATS(ip6_dst_idev(&rt->u.dst), IPSTATS_MIB_FRAGFAILS);
720 dst_release(&rt->u.dst);
721 return err;
722 }
723
724 slow_path:
725 left = skb->len - hlen; /* Space per frame */
726 ptr = hlen; /* Where to start from */
727
728 /*
729 * Fragment the datagram.
730 */
731
732 *prevhdr = NEXTHDR_FRAGMENT;
733
734 /*
735 * Keep copying data until we run out.
736 */
737 while(left > 0) {
738 len = left;
739 /* IF: it doesn't fit, use 'mtu' - the data space left */
740 if (len > mtu)
741 len = mtu;
742 /* IF: we are not sending upto and including the packet end
743 then align the next start on an eight byte boundary */
744 if (len < left) {
745 len &= ~7;
746 }
747 /*
748 * Allocate buffer.
749 */
750
751 if ((frag = alloc_skb(len+hlen+sizeof(struct frag_hdr)+LL_RESERVED_SPACE(rt->u.dst.dev), GFP_ATOMIC)) == NULL) {
752 NETDEBUG(KERN_INFO "IPv6: frag: no memory for new fragment!\n");
753 IP6_INC_STATS(ip6_dst_idev(skb->dst),
754 IPSTATS_MIB_FRAGFAILS);
755 err = -ENOMEM;
756 goto fail;
757 }
758
759 /*
760 * Set up data on packet
761 */
762
763 ip6_copy_metadata(frag, skb);
764 skb_reserve(frag, LL_RESERVED_SPACE(rt->u.dst.dev));
765 skb_put(frag, len + hlen + sizeof(struct frag_hdr));
766 skb_reset_network_header(frag);
767 fh = (struct frag_hdr *)(skb_network_header(frag) + hlen);
768 frag->transport_header = (frag->network_header + hlen +
769 sizeof(struct frag_hdr));
770
771 /*
772 * Charge the memory for the fragment to any owner
773 * it might possess
774 */
775 if (skb->sk)
776 skb_set_owner_w(frag, skb->sk);
777
778 /*
779 * Copy the packet header into the new buffer.
780 */
781 skb_copy_from_linear_data(skb, skb_network_header(frag), hlen);
782
783 /*
784 * Build fragment header.
785 */
786 fh->nexthdr = nexthdr;
787 fh->reserved = 0;
788 if (!frag_id) {
789 ipv6_select_ident(skb, fh);
790 frag_id = fh->identification;
791 } else
792 fh->identification = frag_id;
793
794 /*
795 * Copy a block of the IP datagram.
796 */
797 if (skb_copy_bits(skb, ptr, skb_transport_header(skb), len))
798 BUG();
799 left -= len;
800
801 fh->frag_off = htons(offset);
802 if (left > 0)
803 fh->frag_off |= htons(IP6_MF);
804 ipv6_hdr(frag)->payload_len = htons(frag->len -
805 sizeof(struct ipv6hdr));
806
807 ptr += len;
808 offset += len;
809
810 /*
811 * Put this fragment into the sending queue.
812 */
813 err = output(frag);
814 if (err)
815 goto fail;
816
817 IP6_INC_STATS(ip6_dst_idev(skb->dst), IPSTATS_MIB_FRAGCREATES);
818 }
819 IP6_INC_STATS(ip6_dst_idev(skb->dst),
820 IPSTATS_MIB_FRAGOKS);
821 kfree_skb(skb);
822 return err;
823
824 fail:
825 IP6_INC_STATS(ip6_dst_idev(skb->dst),
826 IPSTATS_MIB_FRAGFAILS);
827 kfree_skb(skb);
828 return err;
829 }
830
831 static inline int ip6_rt_check(struct rt6key *rt_key,
832 struct in6_addr *fl_addr,
833 struct in6_addr *addr_cache)
834 {
835 return ((rt_key->plen != 128 || !ipv6_addr_equal(fl_addr, &rt_key->addr)) &&
836 (addr_cache == NULL || !ipv6_addr_equal(fl_addr, addr_cache)));
837 }
838
839 static struct dst_entry *ip6_sk_dst_check(struct sock *sk,
840 struct dst_entry *dst,
841 struct flowi *fl)
842 {
843 struct ipv6_pinfo *np = inet6_sk(sk);
844 struct rt6_info *rt = (struct rt6_info *)dst;
845
846 if (!dst)
847 goto out;
848
849 /* Yes, checking route validity in not connected
850 * case is not very simple. Take into account,
851 * that we do not support routing by source, TOS,
852 * and MSG_DONTROUTE --ANK (980726)
853 *
854 * 1. ip6_rt_check(): If route was host route,
855 * check that cached destination is current.
856 * If it is network route, we still may
857 * check its validity using saved pointer
858 * to the last used address: daddr_cache.
859 * We do not want to save whole address now,
860 * (because main consumer of this service
861 * is tcp, which has not this problem),
862 * so that the last trick works only on connected
863 * sockets.
864 * 2. oif also should be the same.
865 */
866 if (ip6_rt_check(&rt->rt6i_dst, &fl->fl6_dst, np->daddr_cache) ||
867 #ifdef CONFIG_IPV6_SUBTREES
868 ip6_rt_check(&rt->rt6i_src, &fl->fl6_src, np->saddr_cache) ||
869 #endif
870 (fl->oif && fl->oif != dst->dev->ifindex)) {
871 dst_release(dst);
872 dst = NULL;
873 }
874
875 out:
876 return dst;
877 }
878
879 static int ip6_dst_lookup_tail(struct sock *sk,
880 struct dst_entry **dst, struct flowi *fl)
881 {
882 int err;
883
884 if (*dst == NULL)
885 *dst = ip6_route_output(sk, fl);
886
887 if ((err = (*dst)->error))
888 goto out_err_release;
889
890 if (ipv6_addr_any(&fl->fl6_src)) {
891 err = ipv6_get_saddr(*dst, &fl->fl6_dst, &fl->fl6_src);
892 if (err)
893 goto out_err_release;
894 }
895
896 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
897 /*
898 * Here if the dst entry we've looked up
899 * has a neighbour entry that is in the INCOMPLETE
900 * state and the src address from the flow is
901 * marked as OPTIMISTIC, we release the found
902 * dst entry and replace it instead with the
903 * dst entry of the nexthop router
904 */
905 if (!((*dst)->neighbour->nud_state & NUD_VALID)) {
906 struct inet6_ifaddr *ifp;
907 struct flowi fl_gw;
908 int redirect;
909
910 ifp = ipv6_get_ifaddr(&fl->fl6_src, (*dst)->dev, 1);
911
912 redirect = (ifp && ifp->flags & IFA_F_OPTIMISTIC);
913 if (ifp)
914 in6_ifa_put(ifp);
915
916 if (redirect) {
917 /*
918 * We need to get the dst entry for the
919 * default router instead
920 */
921 dst_release(*dst);
922 memcpy(&fl_gw, fl, sizeof(struct flowi));
923 memset(&fl_gw.fl6_dst, 0, sizeof(struct in6_addr));
924 *dst = ip6_route_output(sk, &fl_gw);
925 if ((err = (*dst)->error))
926 goto out_err_release;
927 }
928 }
929 #endif
930
931 return 0;
932
933 out_err_release:
934 dst_release(*dst);
935 *dst = NULL;
936 return err;
937 }
938
939 /**
940 * ip6_dst_lookup - perform route lookup on flow
941 * @sk: socket which provides route info
942 * @dst: pointer to dst_entry * for result
943 * @fl: flow to lookup
944 *
945 * This function performs a route lookup on the given flow.
946 *
947 * It returns zero on success, or a standard errno code on error.
948 */
949 int ip6_dst_lookup(struct sock *sk, struct dst_entry **dst, struct flowi *fl)
950 {
951 *dst = NULL;
952 return ip6_dst_lookup_tail(sk, dst, fl);
953 }
954 EXPORT_SYMBOL_GPL(ip6_dst_lookup);
955
956 /**
957 * ip6_sk_dst_lookup - perform socket cached route lookup on flow
958 * @sk: socket which provides the dst cache and route info
959 * @dst: pointer to dst_entry * for result
960 * @fl: flow to lookup
961 *
962 * This function performs a route lookup on the given flow with the
963 * possibility of using the cached route in the socket if it is valid.
964 * It will take the socket dst lock when operating on the dst cache.
965 * As a result, this function can only be used in process context.
966 *
967 * It returns zero on success, or a standard errno code on error.
968 */
969 int ip6_sk_dst_lookup(struct sock *sk, struct dst_entry **dst, struct flowi *fl)
970 {
971 *dst = NULL;
972 if (sk) {
973 *dst = sk_dst_check(sk, inet6_sk(sk)->dst_cookie);
974 *dst = ip6_sk_dst_check(sk, *dst, fl);
975 }
976
977 return ip6_dst_lookup_tail(sk, dst, fl);
978 }
979 EXPORT_SYMBOL_GPL(ip6_sk_dst_lookup);
980
981 static inline int ip6_ufo_append_data(struct sock *sk,
982 int getfrag(void *from, char *to, int offset, int len,
983 int odd, struct sk_buff *skb),
984 void *from, int length, int hh_len, int fragheaderlen,
985 int transhdrlen, int mtu,unsigned int flags)
986
987 {
988 struct sk_buff *skb;
989 int err;
990
991 /* There is support for UDP large send offload by network
992 * device, so create one single skb packet containing complete
993 * udp datagram
994 */
995 if ((skb = skb_peek_tail(&sk->sk_write_queue)) == NULL) {
996 skb = sock_alloc_send_skb(sk,
997 hh_len + fragheaderlen + transhdrlen + 20,
998 (flags & MSG_DONTWAIT), &err);
999 if (skb == NULL)
1000 return -ENOMEM;
1001
1002 /* reserve space for Hardware header */
1003 skb_reserve(skb, hh_len);
1004
1005 /* create space for UDP/IP header */
1006 skb_put(skb,fragheaderlen + transhdrlen);
1007
1008 /* initialize network header pointer */
1009 skb_reset_network_header(skb);
1010
1011 /* initialize protocol header pointer */
1012 skb->transport_header = skb->network_header + fragheaderlen;
1013
1014 skb->ip_summed = CHECKSUM_PARTIAL;
1015 skb->csum = 0;
1016 sk->sk_sndmsg_off = 0;
1017 }
1018
1019 err = skb_append_datato_frags(sk,skb, getfrag, from,
1020 (length - transhdrlen));
1021 if (!err) {
1022 struct frag_hdr fhdr;
1023
1024 /* specify the length of each IP datagram fragment*/
1025 skb_shinfo(skb)->gso_size = mtu - fragheaderlen -
1026 sizeof(struct frag_hdr);
1027 skb_shinfo(skb)->gso_type = SKB_GSO_UDP;
1028 ipv6_select_ident(skb, &fhdr);
1029 skb_shinfo(skb)->ip6_frag_id = fhdr.identification;
1030 __skb_queue_tail(&sk->sk_write_queue, skb);
1031
1032 return 0;
1033 }
1034 /* There is not enough support do UPD LSO,
1035 * so follow normal path
1036 */
1037 kfree_skb(skb);
1038
1039 return err;
1040 }
1041
1042 int ip6_append_data(struct sock *sk, int getfrag(void *from, char *to,
1043 int offset, int len, int odd, struct sk_buff *skb),
1044 void *from, int length, int transhdrlen,
1045 int hlimit, int tclass, struct ipv6_txoptions *opt, struct flowi *fl,
1046 struct rt6_info *rt, unsigned int flags)
1047 {
1048 struct inet_sock *inet = inet_sk(sk);
1049 struct ipv6_pinfo *np = inet6_sk(sk);
1050 struct sk_buff *skb;
1051 unsigned int maxfraglen, fragheaderlen;
1052 int exthdrlen;
1053 int hh_len;
1054 int mtu;
1055 int copy;
1056 int err;
1057 int offset = 0;
1058 int csummode = CHECKSUM_NONE;
1059
1060 if (flags&MSG_PROBE)
1061 return 0;
1062 if (skb_queue_empty(&sk->sk_write_queue)) {
1063 /*
1064 * setup for corking
1065 */
1066 if (opt) {
1067 if (np->cork.opt == NULL) {
1068 np->cork.opt = kmalloc(opt->tot_len,
1069 sk->sk_allocation);
1070 if (unlikely(np->cork.opt == NULL))
1071 return -ENOBUFS;
1072 } else if (np->cork.opt->tot_len < opt->tot_len) {
1073 printk(KERN_DEBUG "ip6_append_data: invalid option length\n");
1074 return -EINVAL;
1075 }
1076 memcpy(np->cork.opt, opt, opt->tot_len);
1077 inet->cork.flags |= IPCORK_OPT;
1078 /* need source address above miyazawa*/
1079 }
1080 dst_hold(&rt->u.dst);
1081 np->cork.rt = rt;
1082 inet->cork.fl = *fl;
1083 np->cork.hop_limit = hlimit;
1084 np->cork.tclass = tclass;
1085 mtu = np->pmtudisc == IPV6_PMTUDISC_PROBE ?
1086 rt->u.dst.dev->mtu : dst_mtu(rt->u.dst.path);
1087 if (np->frag_size < mtu) {
1088 if (np->frag_size)
1089 mtu = np->frag_size;
1090 }
1091 inet->cork.fragsize = mtu;
1092 if (dst_allfrag(rt->u.dst.path))
1093 inet->cork.flags |= IPCORK_ALLFRAG;
1094 inet->cork.length = 0;
1095 sk->sk_sndmsg_page = NULL;
1096 sk->sk_sndmsg_off = 0;
1097 exthdrlen = rt->u.dst.header_len + (opt ? opt->opt_flen : 0);
1098 length += exthdrlen;
1099 transhdrlen += exthdrlen;
1100 } else {
1101 rt = np->cork.rt;
1102 fl = &inet->cork.fl;
1103 if (inet->cork.flags & IPCORK_OPT)
1104 opt = np->cork.opt;
1105 transhdrlen = 0;
1106 exthdrlen = 0;
1107 mtu = inet->cork.fragsize;
1108 }
1109
1110 hh_len = LL_RESERVED_SPACE(rt->u.dst.dev);
1111
1112 fragheaderlen = sizeof(struct ipv6hdr) + rt->u.dst.nfheader_len + (opt ? opt->opt_nflen : 0);
1113 maxfraglen = ((mtu - fragheaderlen) & ~7) + fragheaderlen - sizeof(struct frag_hdr);
1114
1115 if (mtu <= sizeof(struct ipv6hdr) + IPV6_MAXPLEN) {
1116 if (inet->cork.length + length > sizeof(struct ipv6hdr) + IPV6_MAXPLEN - fragheaderlen) {
1117 ipv6_local_error(sk, EMSGSIZE, fl, mtu-exthdrlen);
1118 return -EMSGSIZE;
1119 }
1120 }
1121
1122 /*
1123 * Let's try using as much space as possible.
1124 * Use MTU if total length of the message fits into the MTU.
1125 * Otherwise, we need to reserve fragment header and
1126 * fragment alignment (= 8-15 octects, in total).
1127 *
1128 * Note that we may need to "move" the data from the tail of
1129 * of the buffer to the new fragment when we split
1130 * the message.
1131 *
1132 * FIXME: It may be fragmented into multiple chunks
1133 * at once if non-fragmentable extension headers
1134 * are too large.
1135 * --yoshfuji
1136 */
1137
1138 inet->cork.length += length;
1139 if (((length > mtu) && (sk->sk_protocol == IPPROTO_UDP)) &&
1140 (rt->u.dst.dev->features & NETIF_F_UFO)) {
1141
1142 err = ip6_ufo_append_data(sk, getfrag, from, length, hh_len,
1143 fragheaderlen, transhdrlen, mtu,
1144 flags);
1145 if (err)
1146 goto error;
1147 return 0;
1148 }
1149
1150 if ((skb = skb_peek_tail(&sk->sk_write_queue)) == NULL)
1151 goto alloc_new_skb;
1152
1153 while (length > 0) {
1154 /* Check if the remaining data fits into current packet. */
1155 copy = (inet->cork.length <= mtu && !(inet->cork.flags & IPCORK_ALLFRAG) ? mtu : maxfraglen) - skb->len;
1156 if (copy < length)
1157 copy = maxfraglen - skb->len;
1158
1159 if (copy <= 0) {
1160 char *data;
1161 unsigned int datalen;
1162 unsigned int fraglen;
1163 unsigned int fraggap;
1164 unsigned int alloclen;
1165 struct sk_buff *skb_prev;
1166 alloc_new_skb:
1167 skb_prev = skb;
1168
1169 /* There's no room in the current skb */
1170 if (skb_prev)
1171 fraggap = skb_prev->len - maxfraglen;
1172 else
1173 fraggap = 0;
1174
1175 /*
1176 * If remaining data exceeds the mtu,
1177 * we know we need more fragment(s).
1178 */
1179 datalen = length + fraggap;
1180 if (datalen > (inet->cork.length <= mtu && !(inet->cork.flags & IPCORK_ALLFRAG) ? mtu : maxfraglen) - fragheaderlen)
1181 datalen = maxfraglen - fragheaderlen;
1182
1183 fraglen = datalen + fragheaderlen;
1184 if ((flags & MSG_MORE) &&
1185 !(rt->u.dst.dev->features&NETIF_F_SG))
1186 alloclen = mtu;
1187 else
1188 alloclen = datalen + fragheaderlen;
1189
1190 /*
1191 * The last fragment gets additional space at tail.
1192 * Note: we overallocate on fragments with MSG_MODE
1193 * because we have no idea if we're the last one.
1194 */
1195 if (datalen == length + fraggap)
1196 alloclen += rt->u.dst.trailer_len;
1197
1198 /*
1199 * We just reserve space for fragment header.
1200 * Note: this may be overallocation if the message
1201 * (without MSG_MORE) fits into the MTU.
1202 */
1203 alloclen += sizeof(struct frag_hdr);
1204
1205 if (transhdrlen) {
1206 skb = sock_alloc_send_skb(sk,
1207 alloclen + hh_len,
1208 (flags & MSG_DONTWAIT), &err);
1209 } else {
1210 skb = NULL;
1211 if (atomic_read(&sk->sk_wmem_alloc) <=
1212 2 * sk->sk_sndbuf)
1213 skb = sock_wmalloc(sk,
1214 alloclen + hh_len, 1,
1215 sk->sk_allocation);
1216 if (unlikely(skb == NULL))
1217 err = -ENOBUFS;
1218 }
1219 if (skb == NULL)
1220 goto error;
1221 /*
1222 * Fill in the control structures
1223 */
1224 skb->ip_summed = csummode;
1225 skb->csum = 0;
1226 /* reserve for fragmentation */
1227 skb_reserve(skb, hh_len+sizeof(struct frag_hdr));
1228
1229 /*
1230 * Find where to start putting bytes
1231 */
1232 data = skb_put(skb, fraglen);
1233 skb_set_network_header(skb, exthdrlen);
1234 data += fragheaderlen;
1235 skb->transport_header = (skb->network_header +
1236 fragheaderlen);
1237 if (fraggap) {
1238 skb->csum = skb_copy_and_csum_bits(
1239 skb_prev, maxfraglen,
1240 data + transhdrlen, fraggap, 0);
1241 skb_prev->csum = csum_sub(skb_prev->csum,
1242 skb->csum);
1243 data += fraggap;
1244 pskb_trim_unique(skb_prev, maxfraglen);
1245 }
1246 copy = datalen - transhdrlen - fraggap;
1247 if (copy < 0) {
1248 err = -EINVAL;
1249 kfree_skb(skb);
1250 goto error;
1251 } else if (copy > 0 && getfrag(from, data + transhdrlen, offset, copy, fraggap, skb) < 0) {
1252 err = -EFAULT;
1253 kfree_skb(skb);
1254 goto error;
1255 }
1256
1257 offset += copy;
1258 length -= datalen - fraggap;
1259 transhdrlen = 0;
1260 exthdrlen = 0;
1261 csummode = CHECKSUM_NONE;
1262
1263 /*
1264 * Put the packet on the pending queue
1265 */
1266 __skb_queue_tail(&sk->sk_write_queue, skb);
1267 continue;
1268 }
1269
1270 if (copy > length)
1271 copy = length;
1272
1273 if (!(rt->u.dst.dev->features&NETIF_F_SG)) {
1274 unsigned int off;
1275
1276 off = skb->len;
1277 if (getfrag(from, skb_put(skb, copy),
1278 offset, copy, off, skb) < 0) {
1279 __skb_trim(skb, off);
1280 err = -EFAULT;
1281 goto error;
1282 }
1283 } else {
1284 int i = skb_shinfo(skb)->nr_frags;
1285 skb_frag_t *frag = &skb_shinfo(skb)->frags[i-1];
1286 struct page *page = sk->sk_sndmsg_page;
1287 int off = sk->sk_sndmsg_off;
1288 unsigned int left;
1289
1290 if (page && (left = PAGE_SIZE - off) > 0) {
1291 if (copy >= left)
1292 copy = left;
1293 if (page != frag->page) {
1294 if (i == MAX_SKB_FRAGS) {
1295 err = -EMSGSIZE;
1296 goto error;
1297 }
1298 get_page(page);
1299 skb_fill_page_desc(skb, i, page, sk->sk_sndmsg_off, 0);
1300 frag = &skb_shinfo(skb)->frags[i];
1301 }
1302 } else if(i < MAX_SKB_FRAGS) {
1303 if (copy > PAGE_SIZE)
1304 copy = PAGE_SIZE;
1305 page = alloc_pages(sk->sk_allocation, 0);
1306 if (page == NULL) {
1307 err = -ENOMEM;
1308 goto error;
1309 }
1310 sk->sk_sndmsg_page = page;
1311 sk->sk_sndmsg_off = 0;
1312
1313 skb_fill_page_desc(skb, i, page, 0, 0);
1314 frag = &skb_shinfo(skb)->frags[i];
1315 skb->truesize += PAGE_SIZE;
1316 atomic_add(PAGE_SIZE, &sk->sk_wmem_alloc);
1317 } else {
1318 err = -EMSGSIZE;
1319 goto error;
1320 }
1321 if (getfrag(from, page_address(frag->page)+frag->page_offset+frag->size, offset, copy, skb->len, skb) < 0) {
1322 err = -EFAULT;
1323 goto error;
1324 }
1325 sk->sk_sndmsg_off += copy;
1326 frag->size += copy;
1327 skb->len += copy;
1328 skb->data_len += copy;
1329 }
1330 offset += copy;
1331 length -= copy;
1332 }
1333 return 0;
1334 error:
1335 inet->cork.length -= length;
1336 IP6_INC_STATS(rt->rt6i_idev, IPSTATS_MIB_OUTDISCARDS);
1337 return err;
1338 }
1339
1340 int ip6_push_pending_frames(struct sock *sk)
1341 {
1342 struct sk_buff *skb, *tmp_skb;
1343 struct sk_buff **tail_skb;
1344 struct in6_addr final_dst_buf, *final_dst = &final_dst_buf;
1345 struct inet_sock *inet = inet_sk(sk);
1346 struct ipv6_pinfo *np = inet6_sk(sk);
1347 struct ipv6hdr *hdr;
1348 struct ipv6_txoptions *opt = np->cork.opt;
1349 struct rt6_info *rt = np->cork.rt;
1350 struct flowi *fl = &inet->cork.fl;
1351 unsigned char proto = fl->proto;
1352 int err = 0;
1353
1354 if ((skb = __skb_dequeue(&sk->sk_write_queue)) == NULL)
1355 goto out;
1356 tail_skb = &(skb_shinfo(skb)->frag_list);
1357
1358 /* move skb->data to ip header from ext header */
1359 if (skb->data < skb_network_header(skb))
1360 __skb_pull(skb, skb_network_offset(skb));
1361 while ((tmp_skb = __skb_dequeue(&sk->sk_write_queue)) != NULL) {
1362 __skb_pull(tmp_skb, skb_network_header_len(skb));
1363 *tail_skb = tmp_skb;
1364 tail_skb = &(tmp_skb->next);
1365 skb->len += tmp_skb->len;
1366 skb->data_len += tmp_skb->len;
1367 skb->truesize += tmp_skb->truesize;
1368 __sock_put(tmp_skb->sk);
1369 tmp_skb->destructor = NULL;
1370 tmp_skb->sk = NULL;
1371 }
1372
1373 ipv6_addr_copy(final_dst, &fl->fl6_dst);
1374 __skb_pull(skb, skb_network_header_len(skb));
1375 if (opt && opt->opt_flen)
1376 ipv6_push_frag_opts(skb, opt, &proto);
1377 if (opt && opt->opt_nflen)
1378 ipv6_push_nfrag_opts(skb, opt, &proto, &final_dst);
1379
1380 skb_push(skb, sizeof(struct ipv6hdr));
1381 skb_reset_network_header(skb);
1382 hdr = ipv6_hdr(skb);
1383
1384 *(__be32*)hdr = fl->fl6_flowlabel |
1385 htonl(0x60000000 | ((int)np->cork.tclass << 20));
1386
1387 if (skb->len <= sizeof(struct ipv6hdr) + IPV6_MAXPLEN)
1388 hdr->payload_len = htons(skb->len - sizeof(struct ipv6hdr));
1389 else
1390 hdr->payload_len = 0;
1391 hdr->hop_limit = np->cork.hop_limit;
1392 hdr->nexthdr = proto;
1393 ipv6_addr_copy(&hdr->saddr, &fl->fl6_src);
1394 ipv6_addr_copy(&hdr->daddr, final_dst);
1395
1396 skb->priority = sk->sk_priority;
1397
1398 skb->dst = dst_clone(&rt->u.dst);
1399 IP6_INC_STATS(rt->rt6i_idev, IPSTATS_MIB_OUTREQUESTS);
1400 err = NF_HOOK(PF_INET6, NF_IP6_LOCAL_OUT, skb, NULL, skb->dst->dev, dst_output);
1401 if (err) {
1402 if (err > 0)
1403 err = np->recverr ? net_xmit_errno(err) : 0;
1404 if (err)
1405 goto error;
1406 }
1407
1408 out:
1409 inet->cork.flags &= ~IPCORK_OPT;
1410 kfree(np->cork.opt);
1411 np->cork.opt = NULL;
1412 if (np->cork.rt) {
1413 dst_release(&np->cork.rt->u.dst);
1414 np->cork.rt = NULL;
1415 inet->cork.flags &= ~IPCORK_ALLFRAG;
1416 }
1417 memset(&inet->cork.fl, 0, sizeof(inet->cork.fl));
1418 return err;
1419 error:
1420 goto out;
1421 }
1422
1423 void ip6_flush_pending_frames(struct sock *sk)
1424 {
1425 struct inet_sock *inet = inet_sk(sk);
1426 struct ipv6_pinfo *np = inet6_sk(sk);
1427 struct sk_buff *skb;
1428
1429 while ((skb = __skb_dequeue_tail(&sk->sk_write_queue)) != NULL) {
1430 IP6_INC_STATS(ip6_dst_idev(skb->dst),
1431 IPSTATS_MIB_OUTDISCARDS);
1432 kfree_skb(skb);
1433 }
1434
1435 inet->cork.flags &= ~IPCORK_OPT;
1436
1437 kfree(np->cork.opt);
1438 np->cork.opt = NULL;
1439 if (np->cork.rt) {
1440 dst_release(&np->cork.rt->u.dst);
1441 np->cork.rt = NULL;
1442 inet->cork.flags &= ~IPCORK_ALLFRAG;
1443 }
1444 memset(&inet->cork.fl, 0, sizeof(inet->cork.fl));
1445 }
USB Experimental Work