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net: remove ipv6_addr_copy()
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / net / ipv6 / ip6_output.c
1 /*
2 * IPv6 output functions
3 * Linux INET6 implementation
4 *
5 * Authors:
6 * Pedro Roque <roque@di.fc.ul.pt>
7 *
8 * Based on linux/net/ipv4/ip_output.c
9 *
10 * This program is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU General Public License
12 * as published by the Free Software Foundation; either version
13 * 2 of the License, or (at your option) any later version.
14 *
15 * Changes:
16 * A.N.Kuznetsov : airthmetics in fragmentation.
17 * extension headers are implemented.
18 * route changes now work.
19 * ip6_forward does not confuse sniffers.
20 * etc.
21 *
22 * H. von Brand : Added missing #include <linux/string.h>
23 * Imran Patel : frag id should be in NBO
24 * Kazunori MIYAZAWA @USAGI
25 * : add ip6_append_data and related functions
26 * for datagram xmit
27 */
28
29 #include <linux/errno.h>
30 #include <linux/kernel.h>
31 #include <linux/string.h>
32 #include <linux/socket.h>
33 #include <linux/net.h>
34 #include <linux/netdevice.h>
35 #include <linux/if_arp.h>
36 #include <linux/in6.h>
37 #include <linux/tcp.h>
38 #include <linux/route.h>
39 #include <linux/module.h>
40 #include <linux/slab.h>
41
42 #include <linux/netfilter.h>
43 #include <linux/netfilter_ipv6.h>
44
45 #include <net/sock.h>
46 #include <net/snmp.h>
47
48 #include <net/ipv6.h>
49 #include <net/ndisc.h>
50 #include <net/protocol.h>
51 #include <net/ip6_route.h>
52 #include <net/addrconf.h>
53 #include <net/rawv6.h>
54 #include <net/icmp.h>
55 #include <net/xfrm.h>
56 #include <net/checksum.h>
57 #include <linux/mroute6.h>
58
59 int ip6_fragment(struct sk_buff *skb, int (*output)(struct sk_buff *));
60
61 int __ip6_local_out(struct sk_buff *skb)
62 {
63 int len;
64
65 len = skb->len - sizeof(struct ipv6hdr);
66 if (len > IPV6_MAXPLEN)
67 len = 0;
68 ipv6_hdr(skb)->payload_len = htons(len);
69
70 return nf_hook(NFPROTO_IPV6, NF_INET_LOCAL_OUT, skb, NULL,
71 skb_dst(skb)->dev, dst_output);
72 }
73
74 int ip6_local_out(struct sk_buff *skb)
75 {
76 int err;
77
78 err = __ip6_local_out(skb);
79 if (likely(err == 1))
80 err = dst_output(skb);
81
82 return err;
83 }
84 EXPORT_SYMBOL_GPL(ip6_local_out);
85
86 /* dev_loopback_xmit for use with netfilter. */
87 static int ip6_dev_loopback_xmit(struct sk_buff *newskb)
88 {
89 skb_reset_mac_header(newskb);
90 __skb_pull(newskb, skb_network_offset(newskb));
91 newskb->pkt_type = PACKET_LOOPBACK;
92 newskb->ip_summed = CHECKSUM_UNNECESSARY;
93 WARN_ON(!skb_dst(newskb));
94
95 netif_rx_ni(newskb);
96 return 0;
97 }
98
99 static int ip6_finish_output2(struct sk_buff *skb)
100 {
101 struct dst_entry *dst = skb_dst(skb);
102 struct net_device *dev = dst->dev;
103 struct neighbour *neigh;
104
105 skb->protocol = htons(ETH_P_IPV6);
106 skb->dev = dev;
107
108 if (ipv6_addr_is_multicast(&ipv6_hdr(skb)->daddr)) {
109 struct inet6_dev *idev = ip6_dst_idev(skb_dst(skb));
110
111 if (!(dev->flags & IFF_LOOPBACK) && sk_mc_loop(skb->sk) &&
112 ((mroute6_socket(dev_net(dev), skb) &&
113 !(IP6CB(skb)->flags & IP6SKB_FORWARDED)) ||
114 ipv6_chk_mcast_addr(dev, &ipv6_hdr(skb)->daddr,
115 &ipv6_hdr(skb)->saddr))) {
116 struct sk_buff *newskb = skb_clone(skb, GFP_ATOMIC);
117
118 /* Do not check for IFF_ALLMULTI; multicast routing
119 is not supported in any case.
120 */
121 if (newskb)
122 NF_HOOK(NFPROTO_IPV6, NF_INET_POST_ROUTING,
123 newskb, NULL, newskb->dev,
124 ip6_dev_loopback_xmit);
125
126 if (ipv6_hdr(skb)->hop_limit == 0) {
127 IP6_INC_STATS(dev_net(dev), idev,
128 IPSTATS_MIB_OUTDISCARDS);
129 kfree_skb(skb);
130 return 0;
131 }
132 }
133
134 IP6_UPD_PO_STATS(dev_net(dev), idev, IPSTATS_MIB_OUTMCAST,
135 skb->len);
136 }
137
138 rcu_read_lock();
139 neigh = dst_get_neighbour(dst);
140 if (neigh) {
141 int res = neigh_output(neigh, skb);
142
143 rcu_read_unlock();
144 return res;
145 }
146 rcu_read_unlock();
147 IP6_INC_STATS_BH(dev_net(dst->dev),
148 ip6_dst_idev(dst), IPSTATS_MIB_OUTNOROUTES);
149 kfree_skb(skb);
150 return -EINVAL;
151 }
152
153 static int ip6_finish_output(struct sk_buff *skb)
154 {
155 if ((skb->len > ip6_skb_dst_mtu(skb) && !skb_is_gso(skb)) ||
156 dst_allfrag(skb_dst(skb)))
157 return ip6_fragment(skb, ip6_finish_output2);
158 else
159 return ip6_finish_output2(skb);
160 }
161
162 int ip6_output(struct sk_buff *skb)
163 {
164 struct net_device *dev = skb_dst(skb)->dev;
165 struct inet6_dev *idev = ip6_dst_idev(skb_dst(skb));
166 if (unlikely(idev->cnf.disable_ipv6)) {
167 IP6_INC_STATS(dev_net(dev), idev,
168 IPSTATS_MIB_OUTDISCARDS);
169 kfree_skb(skb);
170 return 0;
171 }
172
173 return NF_HOOK_COND(NFPROTO_IPV6, NF_INET_POST_ROUTING, skb, NULL, dev,
174 ip6_finish_output,
175 !(IP6CB(skb)->flags & IP6SKB_REROUTED));
176 }
177
178 /*
179 * xmit an sk_buff (used by TCP, SCTP and DCCP)
180 */
181
182 int ip6_xmit(struct sock *sk, struct sk_buff *skb, struct flowi6 *fl6,
183 struct ipv6_txoptions *opt, int tclass)
184 {
185 struct net *net = sock_net(sk);
186 struct ipv6_pinfo *np = inet6_sk(sk);
187 struct in6_addr *first_hop = &fl6->daddr;
188 struct dst_entry *dst = skb_dst(skb);
189 struct ipv6hdr *hdr;
190 u8 proto = fl6->flowi6_proto;
191 int seg_len = skb->len;
192 int hlimit = -1;
193 u32 mtu;
194
195 if (opt) {
196 unsigned int head_room;
197
198 /* First: exthdrs may take lots of space (~8K for now)
199 MAX_HEADER is not enough.
200 */
201 head_room = opt->opt_nflen + opt->opt_flen;
202 seg_len += head_room;
203 head_room += sizeof(struct ipv6hdr) + LL_RESERVED_SPACE(dst->dev);
204
205 if (skb_headroom(skb) < head_room) {
206 struct sk_buff *skb2 = skb_realloc_headroom(skb, head_room);
207 if (skb2 == NULL) {
208 IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
209 IPSTATS_MIB_OUTDISCARDS);
210 kfree_skb(skb);
211 return -ENOBUFS;
212 }
213 kfree_skb(skb);
214 skb = skb2;
215 skb_set_owner_w(skb, sk);
216 }
217 if (opt->opt_flen)
218 ipv6_push_frag_opts(skb, opt, &proto);
219 if (opt->opt_nflen)
220 ipv6_push_nfrag_opts(skb, opt, &proto, &first_hop);
221 }
222
223 skb_push(skb, sizeof(struct ipv6hdr));
224 skb_reset_network_header(skb);
225 hdr = ipv6_hdr(skb);
226
227 /*
228 * Fill in the IPv6 header
229 */
230 if (np)
231 hlimit = np->hop_limit;
232 if (hlimit < 0)
233 hlimit = ip6_dst_hoplimit(dst);
234
235 *(__be32 *)hdr = htonl(0x60000000 | (tclass << 20)) | fl6->flowlabel;
236
237 hdr->payload_len = htons(seg_len);
238 hdr->nexthdr = proto;
239 hdr->hop_limit = hlimit;
240
241 hdr->saddr = fl6->saddr;
242 hdr->daddr = *first_hop;
243
244 skb->priority = sk->sk_priority;
245 skb->mark = sk->sk_mark;
246
247 mtu = dst_mtu(dst);
248 if ((skb->len <= mtu) || skb->local_df || skb_is_gso(skb)) {
249 IP6_UPD_PO_STATS(net, ip6_dst_idev(skb_dst(skb)),
250 IPSTATS_MIB_OUT, skb->len);
251 return NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_OUT, skb, NULL,
252 dst->dev, dst_output);
253 }
254
255 if (net_ratelimit())
256 printk(KERN_DEBUG "IPv6: sending pkt_too_big to self\n");
257 skb->dev = dst->dev;
258 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
259 IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)), IPSTATS_MIB_FRAGFAILS);
260 kfree_skb(skb);
261 return -EMSGSIZE;
262 }
263
264 EXPORT_SYMBOL(ip6_xmit);
265
266 /*
267 * To avoid extra problems ND packets are send through this
268 * routine. It's code duplication but I really want to avoid
269 * extra checks since ipv6_build_header is used by TCP (which
270 * is for us performance critical)
271 */
272
273 int ip6_nd_hdr(struct sock *sk, struct sk_buff *skb, struct net_device *dev,
274 const struct in6_addr *saddr, const struct in6_addr *daddr,
275 int proto, int len)
276 {
277 struct ipv6_pinfo *np = inet6_sk(sk);
278 struct ipv6hdr *hdr;
279
280 skb->protocol = htons(ETH_P_IPV6);
281 skb->dev = dev;
282
283 skb_reset_network_header(skb);
284 skb_put(skb, sizeof(struct ipv6hdr));
285 hdr = ipv6_hdr(skb);
286
287 *(__be32*)hdr = htonl(0x60000000);
288
289 hdr->payload_len = htons(len);
290 hdr->nexthdr = proto;
291 hdr->hop_limit = np->hop_limit;
292
293 hdr->saddr = *saddr;
294 hdr->daddr = *daddr;
295
296 return 0;
297 }
298
299 static int ip6_call_ra_chain(struct sk_buff *skb, int sel)
300 {
301 struct ip6_ra_chain *ra;
302 struct sock *last = NULL;
303
304 read_lock(&ip6_ra_lock);
305 for (ra = ip6_ra_chain; ra; ra = ra->next) {
306 struct sock *sk = ra->sk;
307 if (sk && ra->sel == sel &&
308 (!sk->sk_bound_dev_if ||
309 sk->sk_bound_dev_if == skb->dev->ifindex)) {
310 if (last) {
311 struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
312 if (skb2)
313 rawv6_rcv(last, skb2);
314 }
315 last = sk;
316 }
317 }
318
319 if (last) {
320 rawv6_rcv(last, skb);
321 read_unlock(&ip6_ra_lock);
322 return 1;
323 }
324 read_unlock(&ip6_ra_lock);
325 return 0;
326 }
327
328 static int ip6_forward_proxy_check(struct sk_buff *skb)
329 {
330 struct ipv6hdr *hdr = ipv6_hdr(skb);
331 u8 nexthdr = hdr->nexthdr;
332 int offset;
333
334 if (ipv6_ext_hdr(nexthdr)) {
335 offset = ipv6_skip_exthdr(skb, sizeof(*hdr), &nexthdr);
336 if (offset < 0)
337 return 0;
338 } else
339 offset = sizeof(struct ipv6hdr);
340
341 if (nexthdr == IPPROTO_ICMPV6) {
342 struct icmp6hdr *icmp6;
343
344 if (!pskb_may_pull(skb, (skb_network_header(skb) +
345 offset + 1 - skb->data)))
346 return 0;
347
348 icmp6 = (struct icmp6hdr *)(skb_network_header(skb) + offset);
349
350 switch (icmp6->icmp6_type) {
351 case NDISC_ROUTER_SOLICITATION:
352 case NDISC_ROUTER_ADVERTISEMENT:
353 case NDISC_NEIGHBOUR_SOLICITATION:
354 case NDISC_NEIGHBOUR_ADVERTISEMENT:
355 case NDISC_REDIRECT:
356 /* For reaction involving unicast neighbor discovery
357 * message destined to the proxied address, pass it to
358 * input function.
359 */
360 return 1;
361 default:
362 break;
363 }
364 }
365
366 /*
367 * The proxying router can't forward traffic sent to a link-local
368 * address, so signal the sender and discard the packet. This
369 * behavior is clarified by the MIPv6 specification.
370 */
371 if (ipv6_addr_type(&hdr->daddr) & IPV6_ADDR_LINKLOCAL) {
372 dst_link_failure(skb);
373 return -1;
374 }
375
376 return 0;
377 }
378
379 static inline int ip6_forward_finish(struct sk_buff *skb)
380 {
381 return dst_output(skb);
382 }
383
384 int ip6_forward(struct sk_buff *skb)
385 {
386 struct dst_entry *dst = skb_dst(skb);
387 struct ipv6hdr *hdr = ipv6_hdr(skb);
388 struct inet6_skb_parm *opt = IP6CB(skb);
389 struct net *net = dev_net(dst->dev);
390 struct neighbour *n;
391 u32 mtu;
392
393 if (net->ipv6.devconf_all->forwarding == 0)
394 goto error;
395
396 if (skb_warn_if_lro(skb))
397 goto drop;
398
399 if (!xfrm6_policy_check(NULL, XFRM_POLICY_FWD, skb)) {
400 IP6_INC_STATS(net, ip6_dst_idev(dst), IPSTATS_MIB_INDISCARDS);
401 goto drop;
402 }
403
404 if (skb->pkt_type != PACKET_HOST)
405 goto drop;
406
407 skb_forward_csum(skb);
408
409 /*
410 * We DO NOT make any processing on
411 * RA packets, pushing them to user level AS IS
412 * without ane WARRANTY that application will be able
413 * to interpret them. The reason is that we
414 * cannot make anything clever here.
415 *
416 * We are not end-node, so that if packet contains
417 * AH/ESP, we cannot make anything.
418 * Defragmentation also would be mistake, RA packets
419 * cannot be fragmented, because there is no warranty
420 * that different fragments will go along one path. --ANK
421 */
422 if (opt->ra) {
423 u8 *ptr = skb_network_header(skb) + opt->ra;
424 if (ip6_call_ra_chain(skb, (ptr[2]<<8) + ptr[3]))
425 return 0;
426 }
427
428 /*
429 * check and decrement ttl
430 */
431 if (hdr->hop_limit <= 1) {
432 /* Force OUTPUT device used as source address */
433 skb->dev = dst->dev;
434 icmpv6_send(skb, ICMPV6_TIME_EXCEED, ICMPV6_EXC_HOPLIMIT, 0);
435 IP6_INC_STATS_BH(net,
436 ip6_dst_idev(dst), IPSTATS_MIB_INHDRERRORS);
437
438 kfree_skb(skb);
439 return -ETIMEDOUT;
440 }
441
442 /* XXX: idev->cnf.proxy_ndp? */
443 if (net->ipv6.devconf_all->proxy_ndp &&
444 pneigh_lookup(&nd_tbl, net, &hdr->daddr, skb->dev, 0)) {
445 int proxied = ip6_forward_proxy_check(skb);
446 if (proxied > 0)
447 return ip6_input(skb);
448 else if (proxied < 0) {
449 IP6_INC_STATS(net, ip6_dst_idev(dst),
450 IPSTATS_MIB_INDISCARDS);
451 goto drop;
452 }
453 }
454
455 if (!xfrm6_route_forward(skb)) {
456 IP6_INC_STATS(net, ip6_dst_idev(dst), IPSTATS_MIB_INDISCARDS);
457 goto drop;
458 }
459 dst = skb_dst(skb);
460
461 /* IPv6 specs say nothing about it, but it is clear that we cannot
462 send redirects to source routed frames.
463 We don't send redirects to frames decapsulated from IPsec.
464 */
465 n = dst_get_neighbour(dst);
466 if (skb->dev == dst->dev && n && opt->srcrt == 0 && !skb_sec_path(skb)) {
467 struct in6_addr *target = NULL;
468 struct rt6_info *rt;
469
470 /*
471 * incoming and outgoing devices are the same
472 * send a redirect.
473 */
474
475 rt = (struct rt6_info *) dst;
476 if ((rt->rt6i_flags & RTF_GATEWAY))
477 target = (struct in6_addr*)&n->primary_key;
478 else
479 target = &hdr->daddr;
480
481 if (!rt->rt6i_peer)
482 rt6_bind_peer(rt, 1);
483
484 /* Limit redirects both by destination (here)
485 and by source (inside ndisc_send_redirect)
486 */
487 if (inet_peer_xrlim_allow(rt->rt6i_peer, 1*HZ))
488 ndisc_send_redirect(skb, n, target);
489 } else {
490 int addrtype = ipv6_addr_type(&hdr->saddr);
491
492 /* This check is security critical. */
493 if (addrtype == IPV6_ADDR_ANY ||
494 addrtype & (IPV6_ADDR_MULTICAST | IPV6_ADDR_LOOPBACK))
495 goto error;
496 if (addrtype & IPV6_ADDR_LINKLOCAL) {
497 icmpv6_send(skb, ICMPV6_DEST_UNREACH,
498 ICMPV6_NOT_NEIGHBOUR, 0);
499 goto error;
500 }
501 }
502
503 mtu = dst_mtu(dst);
504 if (mtu < IPV6_MIN_MTU)
505 mtu = IPV6_MIN_MTU;
506
507 if (skb->len > mtu && !skb_is_gso(skb)) {
508 /* Again, force OUTPUT device used as source address */
509 skb->dev = dst->dev;
510 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
511 IP6_INC_STATS_BH(net,
512 ip6_dst_idev(dst), IPSTATS_MIB_INTOOBIGERRORS);
513 IP6_INC_STATS_BH(net,
514 ip6_dst_idev(dst), IPSTATS_MIB_FRAGFAILS);
515 kfree_skb(skb);
516 return -EMSGSIZE;
517 }
518
519 if (skb_cow(skb, dst->dev->hard_header_len)) {
520 IP6_INC_STATS(net, ip6_dst_idev(dst), IPSTATS_MIB_OUTDISCARDS);
521 goto drop;
522 }
523
524 hdr = ipv6_hdr(skb);
525
526 /* Mangling hops number delayed to point after skb COW */
527
528 hdr->hop_limit--;
529
530 IP6_INC_STATS_BH(net, ip6_dst_idev(dst), IPSTATS_MIB_OUTFORWDATAGRAMS);
531 return NF_HOOK(NFPROTO_IPV6, NF_INET_FORWARD, skb, skb->dev, dst->dev,
532 ip6_forward_finish);
533
534 error:
535 IP6_INC_STATS_BH(net, ip6_dst_idev(dst), IPSTATS_MIB_INADDRERRORS);
536 drop:
537 kfree_skb(skb);
538 return -EINVAL;
539 }
540
541 static void ip6_copy_metadata(struct sk_buff *to, struct sk_buff *from)
542 {
543 to->pkt_type = from->pkt_type;
544 to->priority = from->priority;
545 to->protocol = from->protocol;
546 skb_dst_drop(to);
547 skb_dst_set(to, dst_clone(skb_dst(from)));
548 to->dev = from->dev;
549 to->mark = from->mark;
550
551 #ifdef CONFIG_NET_SCHED
552 to->tc_index = from->tc_index;
553 #endif
554 nf_copy(to, from);
555 #if defined(CONFIG_NETFILTER_XT_TARGET_TRACE) || \
556 defined(CONFIG_NETFILTER_XT_TARGET_TRACE_MODULE)
557 to->nf_trace = from->nf_trace;
558 #endif
559 skb_copy_secmark(to, from);
560 }
561
562 int ip6_find_1stfragopt(struct sk_buff *skb, u8 **nexthdr)
563 {
564 u16 offset = sizeof(struct ipv6hdr);
565 struct ipv6_opt_hdr *exthdr =
566 (struct ipv6_opt_hdr *)(ipv6_hdr(skb) + 1);
567 unsigned int packet_len = skb->tail - skb->network_header;
568 int found_rhdr = 0;
569 *nexthdr = &ipv6_hdr(skb)->nexthdr;
570
571 while (offset + 1 <= packet_len) {
572
573 switch (**nexthdr) {
574
575 case NEXTHDR_HOP:
576 break;
577 case NEXTHDR_ROUTING:
578 found_rhdr = 1;
579 break;
580 case NEXTHDR_DEST:
581 #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
582 if (ipv6_find_tlv(skb, offset, IPV6_TLV_HAO) >= 0)
583 break;
584 #endif
585 if (found_rhdr)
586 return offset;
587 break;
588 default :
589 return offset;
590 }
591
592 offset += ipv6_optlen(exthdr);
593 *nexthdr = &exthdr->nexthdr;
594 exthdr = (struct ipv6_opt_hdr *)(skb_network_header(skb) +
595 offset);
596 }
597
598 return offset;
599 }
600
601 void ipv6_select_ident(struct frag_hdr *fhdr, struct rt6_info *rt)
602 {
603 static atomic_t ipv6_fragmentation_id;
604 int old, new;
605
606 if (rt) {
607 struct inet_peer *peer;
608
609 if (!rt->rt6i_peer)
610 rt6_bind_peer(rt, 1);
611 peer = rt->rt6i_peer;
612 if (peer) {
613 fhdr->identification = htonl(inet_getid(peer, 0));
614 return;
615 }
616 }
617 do {
618 old = atomic_read(&ipv6_fragmentation_id);
619 new = old + 1;
620 if (!new)
621 new = 1;
622 } while (atomic_cmpxchg(&ipv6_fragmentation_id, old, new) != old);
623 fhdr->identification = htonl(new);
624 }
625
626 int ip6_fragment(struct sk_buff *skb, int (*output)(struct sk_buff *))
627 {
628 struct sk_buff *frag;
629 struct rt6_info *rt = (struct rt6_info*)skb_dst(skb);
630 struct ipv6_pinfo *np = skb->sk ? inet6_sk(skb->sk) : NULL;
631 struct ipv6hdr *tmp_hdr;
632 struct frag_hdr *fh;
633 unsigned int mtu, hlen, left, len;
634 int hroom, troom;
635 __be32 frag_id = 0;
636 int ptr, offset = 0, err=0;
637 u8 *prevhdr, nexthdr = 0;
638 struct net *net = dev_net(skb_dst(skb)->dev);
639
640 hlen = ip6_find_1stfragopt(skb, &prevhdr);
641 nexthdr = *prevhdr;
642
643 mtu = ip6_skb_dst_mtu(skb);
644
645 /* We must not fragment if the socket is set to force MTU discovery
646 * or if the skb it not generated by a local socket.
647 */
648 if (!skb->local_df && skb->len > mtu) {
649 skb->dev = skb_dst(skb)->dev;
650 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
651 IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
652 IPSTATS_MIB_FRAGFAILS);
653 kfree_skb(skb);
654 return -EMSGSIZE;
655 }
656
657 if (np && np->frag_size < mtu) {
658 if (np->frag_size)
659 mtu = np->frag_size;
660 }
661 mtu -= hlen + sizeof(struct frag_hdr);
662
663 if (skb_has_frag_list(skb)) {
664 int first_len = skb_pagelen(skb);
665 struct sk_buff *frag2;
666
667 if (first_len - hlen > mtu ||
668 ((first_len - hlen) & 7) ||
669 skb_cloned(skb))
670 goto slow_path;
671
672 skb_walk_frags(skb, frag) {
673 /* Correct geometry. */
674 if (frag->len > mtu ||
675 ((frag->len & 7) && frag->next) ||
676 skb_headroom(frag) < hlen)
677 goto slow_path_clean;
678
679 /* Partially cloned skb? */
680 if (skb_shared(frag))
681 goto slow_path_clean;
682
683 BUG_ON(frag->sk);
684 if (skb->sk) {
685 frag->sk = skb->sk;
686 frag->destructor = sock_wfree;
687 }
688 skb->truesize -= frag->truesize;
689 }
690
691 err = 0;
692 offset = 0;
693 frag = skb_shinfo(skb)->frag_list;
694 skb_frag_list_init(skb);
695 /* BUILD HEADER */
696
697 *prevhdr = NEXTHDR_FRAGMENT;
698 tmp_hdr = kmemdup(skb_network_header(skb), hlen, GFP_ATOMIC);
699 if (!tmp_hdr) {
700 IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
701 IPSTATS_MIB_FRAGFAILS);
702 return -ENOMEM;
703 }
704
705 __skb_pull(skb, hlen);
706 fh = (struct frag_hdr*)__skb_push(skb, sizeof(struct frag_hdr));
707 __skb_push(skb, hlen);
708 skb_reset_network_header(skb);
709 memcpy(skb_network_header(skb), tmp_hdr, hlen);
710
711 ipv6_select_ident(fh, rt);
712 fh->nexthdr = nexthdr;
713 fh->reserved = 0;
714 fh->frag_off = htons(IP6_MF);
715 frag_id = fh->identification;
716
717 first_len = skb_pagelen(skb);
718 skb->data_len = first_len - skb_headlen(skb);
719 skb->len = first_len;
720 ipv6_hdr(skb)->payload_len = htons(first_len -
721 sizeof(struct ipv6hdr));
722
723 dst_hold(&rt->dst);
724
725 for (;;) {
726 /* Prepare header of the next frame,
727 * before previous one went down. */
728 if (frag) {
729 frag->ip_summed = CHECKSUM_NONE;
730 skb_reset_transport_header(frag);
731 fh = (struct frag_hdr*)__skb_push(frag, sizeof(struct frag_hdr));
732 __skb_push(frag, hlen);
733 skb_reset_network_header(frag);
734 memcpy(skb_network_header(frag), tmp_hdr,
735 hlen);
736 offset += skb->len - hlen - sizeof(struct frag_hdr);
737 fh->nexthdr = nexthdr;
738 fh->reserved = 0;
739 fh->frag_off = htons(offset);
740 if (frag->next != NULL)
741 fh->frag_off |= htons(IP6_MF);
742 fh->identification = frag_id;
743 ipv6_hdr(frag)->payload_len =
744 htons(frag->len -
745 sizeof(struct ipv6hdr));
746 ip6_copy_metadata(frag, skb);
747 }
748
749 err = output(skb);
750 if(!err)
751 IP6_INC_STATS(net, ip6_dst_idev(&rt->dst),
752 IPSTATS_MIB_FRAGCREATES);
753
754 if (err || !frag)
755 break;
756
757 skb = frag;
758 frag = skb->next;
759 skb->next = NULL;
760 }
761
762 kfree(tmp_hdr);
763
764 if (err == 0) {
765 IP6_INC_STATS(net, ip6_dst_idev(&rt->dst),
766 IPSTATS_MIB_FRAGOKS);
767 dst_release(&rt->dst);
768 return 0;
769 }
770
771 while (frag) {
772 skb = frag->next;
773 kfree_skb(frag);
774 frag = skb;
775 }
776
777 IP6_INC_STATS(net, ip6_dst_idev(&rt->dst),
778 IPSTATS_MIB_FRAGFAILS);
779 dst_release(&rt->dst);
780 return err;
781
782 slow_path_clean:
783 skb_walk_frags(skb, frag2) {
784 if (frag2 == frag)
785 break;
786 frag2->sk = NULL;
787 frag2->destructor = NULL;
788 skb->truesize += frag2->truesize;
789 }
790 }
791
792 slow_path:
793 left = skb->len - hlen; /* Space per frame */
794 ptr = hlen; /* Where to start from */
795
796 /*
797 * Fragment the datagram.
798 */
799
800 *prevhdr = NEXTHDR_FRAGMENT;
801 hroom = LL_RESERVED_SPACE(rt->dst.dev);
802 troom = rt->dst.dev->needed_tailroom;
803
804 /*
805 * Keep copying data until we run out.
806 */
807 while(left > 0) {
808 len = left;
809 /* IF: it doesn't fit, use 'mtu' - the data space left */
810 if (len > mtu)
811 len = mtu;
812 /* IF: we are not sending up to and including the packet end
813 then align the next start on an eight byte boundary */
814 if (len < left) {
815 len &= ~7;
816 }
817 /*
818 * Allocate buffer.
819 */
820
821 if ((frag = alloc_skb(len + hlen + sizeof(struct frag_hdr) +
822 hroom + troom, GFP_ATOMIC)) == NULL) {
823 NETDEBUG(KERN_INFO "IPv6: frag: no memory for new fragment!\n");
824 IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
825 IPSTATS_MIB_FRAGFAILS);
826 err = -ENOMEM;
827 goto fail;
828 }
829
830 /*
831 * Set up data on packet
832 */
833
834 ip6_copy_metadata(frag, skb);
835 skb_reserve(frag, hroom);
836 skb_put(frag, len + hlen + sizeof(struct frag_hdr));
837 skb_reset_network_header(frag);
838 fh = (struct frag_hdr *)(skb_network_header(frag) + hlen);
839 frag->transport_header = (frag->network_header + hlen +
840 sizeof(struct frag_hdr));
841
842 /*
843 * Charge the memory for the fragment to any owner
844 * it might possess
845 */
846 if (skb->sk)
847 skb_set_owner_w(frag, skb->sk);
848
849 /*
850 * Copy the packet header into the new buffer.
851 */
852 skb_copy_from_linear_data(skb, skb_network_header(frag), hlen);
853
854 /*
855 * Build fragment header.
856 */
857 fh->nexthdr = nexthdr;
858 fh->reserved = 0;
859 if (!frag_id) {
860 ipv6_select_ident(fh, rt);
861 frag_id = fh->identification;
862 } else
863 fh->identification = frag_id;
864
865 /*
866 * Copy a block of the IP datagram.
867 */
868 if (skb_copy_bits(skb, ptr, skb_transport_header(frag), len))
869 BUG();
870 left -= len;
871
872 fh->frag_off = htons(offset);
873 if (left > 0)
874 fh->frag_off |= htons(IP6_MF);
875 ipv6_hdr(frag)->payload_len = htons(frag->len -
876 sizeof(struct ipv6hdr));
877
878 ptr += len;
879 offset += len;
880
881 /*
882 * Put this fragment into the sending queue.
883 */
884 err = output(frag);
885 if (err)
886 goto fail;
887
888 IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
889 IPSTATS_MIB_FRAGCREATES);
890 }
891 IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
892 IPSTATS_MIB_FRAGOKS);
893 kfree_skb(skb);
894 return err;
895
896 fail:
897 IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
898 IPSTATS_MIB_FRAGFAILS);
899 kfree_skb(skb);
900 return err;
901 }
902
903 static inline int ip6_rt_check(const struct rt6key *rt_key,
904 const struct in6_addr *fl_addr,
905 const struct in6_addr *addr_cache)
906 {
907 return (rt_key->plen != 128 || !ipv6_addr_equal(fl_addr, &rt_key->addr)) &&
908 (addr_cache == NULL || !ipv6_addr_equal(fl_addr, addr_cache));
909 }
910
911 static struct dst_entry *ip6_sk_dst_check(struct sock *sk,
912 struct dst_entry *dst,
913 const struct flowi6 *fl6)
914 {
915 struct ipv6_pinfo *np = inet6_sk(sk);
916 struct rt6_info *rt = (struct rt6_info *)dst;
917
918 if (!dst)
919 goto out;
920
921 /* Yes, checking route validity in not connected
922 * case is not very simple. Take into account,
923 * that we do not support routing by source, TOS,
924 * and MSG_DONTROUTE --ANK (980726)
925 *
926 * 1. ip6_rt_check(): If route was host route,
927 * check that cached destination is current.
928 * If it is network route, we still may
929 * check its validity using saved pointer
930 * to the last used address: daddr_cache.
931 * We do not want to save whole address now,
932 * (because main consumer of this service
933 * is tcp, which has not this problem),
934 * so that the last trick works only on connected
935 * sockets.
936 * 2. oif also should be the same.
937 */
938 if (ip6_rt_check(&rt->rt6i_dst, &fl6->daddr, np->daddr_cache) ||
939 #ifdef CONFIG_IPV6_SUBTREES
940 ip6_rt_check(&rt->rt6i_src, &fl6->saddr, np->saddr_cache) ||
941 #endif
942 (fl6->flowi6_oif && fl6->flowi6_oif != dst->dev->ifindex)) {
943 dst_release(dst);
944 dst = NULL;
945 }
946
947 out:
948 return dst;
949 }
950
951 static int ip6_dst_lookup_tail(struct sock *sk,
952 struct dst_entry **dst, struct flowi6 *fl6)
953 {
954 struct net *net = sock_net(sk);
955 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
956 struct neighbour *n;
957 #endif
958 int err;
959
960 if (*dst == NULL)
961 *dst = ip6_route_output(net, sk, fl6);
962
963 if ((err = (*dst)->error))
964 goto out_err_release;
965
966 if (ipv6_addr_any(&fl6->saddr)) {
967 struct rt6_info *rt = (struct rt6_info *) *dst;
968 err = ip6_route_get_saddr(net, rt, &fl6->daddr,
969 sk ? inet6_sk(sk)->srcprefs : 0,
970 &fl6->saddr);
971 if (err)
972 goto out_err_release;
973 }
974
975 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
976 /*
977 * Here if the dst entry we've looked up
978 * has a neighbour entry that is in the INCOMPLETE
979 * state and the src address from the flow is
980 * marked as OPTIMISTIC, we release the found
981 * dst entry and replace it instead with the
982 * dst entry of the nexthop router
983 */
984 rcu_read_lock();
985 n = dst_get_neighbour(*dst);
986 if (n && !(n->nud_state & NUD_VALID)) {
987 struct inet6_ifaddr *ifp;
988 struct flowi6 fl_gw6;
989 int redirect;
990
991 rcu_read_unlock();
992 ifp = ipv6_get_ifaddr(net, &fl6->saddr,
993 (*dst)->dev, 1);
994
995 redirect = (ifp && ifp->flags & IFA_F_OPTIMISTIC);
996 if (ifp)
997 in6_ifa_put(ifp);
998
999 if (redirect) {
1000 /*
1001 * We need to get the dst entry for the
1002 * default router instead
1003 */
1004 dst_release(*dst);
1005 memcpy(&fl_gw6, fl6, sizeof(struct flowi6));
1006 memset(&fl_gw6.daddr, 0, sizeof(struct in6_addr));
1007 *dst = ip6_route_output(net, sk, &fl_gw6);
1008 if ((err = (*dst)->error))
1009 goto out_err_release;
1010 }
1011 } else {
1012 rcu_read_unlock();
1013 }
1014 #endif
1015
1016 return 0;
1017
1018 out_err_release:
1019 if (err == -ENETUNREACH)
1020 IP6_INC_STATS_BH(net, NULL, IPSTATS_MIB_OUTNOROUTES);
1021 dst_release(*dst);
1022 *dst = NULL;
1023 return err;
1024 }
1025
1026 /**
1027 * ip6_dst_lookup - perform route lookup on flow
1028 * @sk: socket which provides route info
1029 * @dst: pointer to dst_entry * for result
1030 * @fl6: flow to lookup
1031 *
1032 * This function performs a route lookup on the given flow.
1033 *
1034 * It returns zero on success, or a standard errno code on error.
1035 */
1036 int ip6_dst_lookup(struct sock *sk, struct dst_entry **dst, struct flowi6 *fl6)
1037 {
1038 *dst = NULL;
1039 return ip6_dst_lookup_tail(sk, dst, fl6);
1040 }
1041 EXPORT_SYMBOL_GPL(ip6_dst_lookup);
1042
1043 /**
1044 * ip6_dst_lookup_flow - perform route lookup on flow with ipsec
1045 * @sk: socket which provides route info
1046 * @fl6: flow to lookup
1047 * @final_dst: final destination address for ipsec lookup
1048 * @can_sleep: we are in a sleepable context
1049 *
1050 * This function performs a route lookup on the given flow.
1051 *
1052 * It returns a valid dst pointer on success, or a pointer encoded
1053 * error code.
1054 */
1055 struct dst_entry *ip6_dst_lookup_flow(struct sock *sk, struct flowi6 *fl6,
1056 const struct in6_addr *final_dst,
1057 bool can_sleep)
1058 {
1059 struct dst_entry *dst = NULL;
1060 int err;
1061
1062 err = ip6_dst_lookup_tail(sk, &dst, fl6);
1063 if (err)
1064 return ERR_PTR(err);
1065 if (final_dst)
1066 fl6->daddr = *final_dst;
1067 if (can_sleep)
1068 fl6->flowi6_flags |= FLOWI_FLAG_CAN_SLEEP;
1069
1070 return xfrm_lookup(sock_net(sk), dst, flowi6_to_flowi(fl6), sk, 0);
1071 }
1072 EXPORT_SYMBOL_GPL(ip6_dst_lookup_flow);
1073
1074 /**
1075 * ip6_sk_dst_lookup_flow - perform socket cached route lookup on flow
1076 * @sk: socket which provides the dst cache and route info
1077 * @fl6: flow to lookup
1078 * @final_dst: final destination address for ipsec lookup
1079 * @can_sleep: we are in a sleepable context
1080 *
1081 * This function performs a route lookup on the given flow with the
1082 * possibility of using the cached route in the socket if it is valid.
1083 * It will take the socket dst lock when operating on the dst cache.
1084 * As a result, this function can only be used in process context.
1085 *
1086 * It returns a valid dst pointer on success, or a pointer encoded
1087 * error code.
1088 */
1089 struct dst_entry *ip6_sk_dst_lookup_flow(struct sock *sk, struct flowi6 *fl6,
1090 const struct in6_addr *final_dst,
1091 bool can_sleep)
1092 {
1093 struct dst_entry *dst = sk_dst_check(sk, inet6_sk(sk)->dst_cookie);
1094 int err;
1095
1096 dst = ip6_sk_dst_check(sk, dst, fl6);
1097
1098 err = ip6_dst_lookup_tail(sk, &dst, fl6);
1099 if (err)
1100 return ERR_PTR(err);
1101 if (final_dst)
1102 fl6->daddr = *final_dst;
1103 if (can_sleep)
1104 fl6->flowi6_flags |= FLOWI_FLAG_CAN_SLEEP;
1105
1106 return xfrm_lookup(sock_net(sk), dst, flowi6_to_flowi(fl6), sk, 0);
1107 }
1108 EXPORT_SYMBOL_GPL(ip6_sk_dst_lookup_flow);
1109
1110 static inline int ip6_ufo_append_data(struct sock *sk,
1111 int getfrag(void *from, char *to, int offset, int len,
1112 int odd, struct sk_buff *skb),
1113 void *from, int length, int hh_len, int fragheaderlen,
1114 int transhdrlen, int mtu,unsigned int flags,
1115 struct rt6_info *rt)
1116
1117 {
1118 struct sk_buff *skb;
1119 int err;
1120
1121 /* There is support for UDP large send offload by network
1122 * device, so create one single skb packet containing complete
1123 * udp datagram
1124 */
1125 if ((skb = skb_peek_tail(&sk->sk_write_queue)) == NULL) {
1126 skb = sock_alloc_send_skb(sk,
1127 hh_len + fragheaderlen + transhdrlen + 20,
1128 (flags & MSG_DONTWAIT), &err);
1129 if (skb == NULL)
1130 return err;
1131
1132 /* reserve space for Hardware header */
1133 skb_reserve(skb, hh_len);
1134
1135 /* create space for UDP/IP header */
1136 skb_put(skb,fragheaderlen + transhdrlen);
1137
1138 /* initialize network header pointer */
1139 skb_reset_network_header(skb);
1140
1141 /* initialize protocol header pointer */
1142 skb->transport_header = skb->network_header + fragheaderlen;
1143
1144 skb->ip_summed = CHECKSUM_PARTIAL;
1145 skb->csum = 0;
1146 }
1147
1148 err = skb_append_datato_frags(sk,skb, getfrag, from,
1149 (length - transhdrlen));
1150 if (!err) {
1151 struct frag_hdr fhdr;
1152
1153 /* Specify the length of each IPv6 datagram fragment.
1154 * It has to be a multiple of 8.
1155 */
1156 skb_shinfo(skb)->gso_size = (mtu - fragheaderlen -
1157 sizeof(struct frag_hdr)) & ~7;
1158 skb_shinfo(skb)->gso_type = SKB_GSO_UDP;
1159 ipv6_select_ident(&fhdr, rt);
1160 skb_shinfo(skb)->ip6_frag_id = fhdr.identification;
1161 __skb_queue_tail(&sk->sk_write_queue, skb);
1162
1163 return 0;
1164 }
1165 /* There is not enough support do UPD LSO,
1166 * so follow normal path
1167 */
1168 kfree_skb(skb);
1169
1170 return err;
1171 }
1172
1173 static inline struct ipv6_opt_hdr *ip6_opt_dup(struct ipv6_opt_hdr *src,
1174 gfp_t gfp)
1175 {
1176 return src ? kmemdup(src, (src->hdrlen + 1) * 8, gfp) : NULL;
1177 }
1178
1179 static inline struct ipv6_rt_hdr *ip6_rthdr_dup(struct ipv6_rt_hdr *src,
1180 gfp_t gfp)
1181 {
1182 return src ? kmemdup(src, (src->hdrlen + 1) * 8, gfp) : NULL;
1183 }
1184
1185 int ip6_append_data(struct sock *sk, int getfrag(void *from, char *to,
1186 int offset, int len, int odd, struct sk_buff *skb),
1187 void *from, int length, int transhdrlen,
1188 int hlimit, int tclass, struct ipv6_txoptions *opt, struct flowi6 *fl6,
1189 struct rt6_info *rt, unsigned int flags, int dontfrag)
1190 {
1191 struct inet_sock *inet = inet_sk(sk);
1192 struct ipv6_pinfo *np = inet6_sk(sk);
1193 struct inet_cork *cork;
1194 struct sk_buff *skb;
1195 unsigned int maxfraglen, fragheaderlen;
1196 int exthdrlen;
1197 int dst_exthdrlen;
1198 int hh_len;
1199 int mtu;
1200 int copy;
1201 int err;
1202 int offset = 0;
1203 int csummode = CHECKSUM_NONE;
1204 __u8 tx_flags = 0;
1205
1206 if (flags&MSG_PROBE)
1207 return 0;
1208 cork = &inet->cork.base;
1209 if (skb_queue_empty(&sk->sk_write_queue)) {
1210 /*
1211 * setup for corking
1212 */
1213 if (opt) {
1214 if (WARN_ON(np->cork.opt))
1215 return -EINVAL;
1216
1217 np->cork.opt = kmalloc(opt->tot_len, sk->sk_allocation);
1218 if (unlikely(np->cork.opt == NULL))
1219 return -ENOBUFS;
1220
1221 np->cork.opt->tot_len = opt->tot_len;
1222 np->cork.opt->opt_flen = opt->opt_flen;
1223 np->cork.opt->opt_nflen = opt->opt_nflen;
1224
1225 np->cork.opt->dst0opt = ip6_opt_dup(opt->dst0opt,
1226 sk->sk_allocation);
1227 if (opt->dst0opt && !np->cork.opt->dst0opt)
1228 return -ENOBUFS;
1229
1230 np->cork.opt->dst1opt = ip6_opt_dup(opt->dst1opt,
1231 sk->sk_allocation);
1232 if (opt->dst1opt && !np->cork.opt->dst1opt)
1233 return -ENOBUFS;
1234
1235 np->cork.opt->hopopt = ip6_opt_dup(opt->hopopt,
1236 sk->sk_allocation);
1237 if (opt->hopopt && !np->cork.opt->hopopt)
1238 return -ENOBUFS;
1239
1240 np->cork.opt->srcrt = ip6_rthdr_dup(opt->srcrt,
1241 sk->sk_allocation);
1242 if (opt->srcrt && !np->cork.opt->srcrt)
1243 return -ENOBUFS;
1244
1245 /* need source address above miyazawa*/
1246 }
1247 dst_hold(&rt->dst);
1248 cork->dst = &rt->dst;
1249 inet->cork.fl.u.ip6 = *fl6;
1250 np->cork.hop_limit = hlimit;
1251 np->cork.tclass = tclass;
1252 mtu = np->pmtudisc == IPV6_PMTUDISC_PROBE ?
1253 rt->dst.dev->mtu : dst_mtu(&rt->dst);
1254 if (np->frag_size < mtu) {
1255 if (np->frag_size)
1256 mtu = np->frag_size;
1257 }
1258 cork->fragsize = mtu;
1259 if (dst_allfrag(rt->dst.path))
1260 cork->flags |= IPCORK_ALLFRAG;
1261 cork->length = 0;
1262 sk->sk_sndmsg_page = NULL;
1263 sk->sk_sndmsg_off = 0;
1264 exthdrlen = (opt ? opt->opt_flen : 0) - rt->rt6i_nfheader_len;
1265 length += exthdrlen;
1266 transhdrlen += exthdrlen;
1267 dst_exthdrlen = rt->dst.header_len;
1268 } else {
1269 rt = (struct rt6_info *)cork->dst;
1270 fl6 = &inet->cork.fl.u.ip6;
1271 opt = np->cork.opt;
1272 transhdrlen = 0;
1273 exthdrlen = 0;
1274 dst_exthdrlen = 0;
1275 mtu = cork->fragsize;
1276 }
1277
1278 hh_len = LL_RESERVED_SPACE(rt->dst.dev);
1279
1280 fragheaderlen = sizeof(struct ipv6hdr) + rt->rt6i_nfheader_len +
1281 (opt ? opt->opt_nflen : 0);
1282 maxfraglen = ((mtu - fragheaderlen) & ~7) + fragheaderlen - sizeof(struct frag_hdr);
1283
1284 if (mtu <= sizeof(struct ipv6hdr) + IPV6_MAXPLEN) {
1285 if (cork->length + length > sizeof(struct ipv6hdr) + IPV6_MAXPLEN - fragheaderlen) {
1286 ipv6_local_error(sk, EMSGSIZE, fl6, mtu-exthdrlen);
1287 return -EMSGSIZE;
1288 }
1289 }
1290
1291 /* For UDP, check if TX timestamp is enabled */
1292 if (sk->sk_type == SOCK_DGRAM) {
1293 err = sock_tx_timestamp(sk, &tx_flags);
1294 if (err)
1295 goto error;
1296 }
1297
1298 /*
1299 * Let's try using as much space as possible.
1300 * Use MTU if total length of the message fits into the MTU.
1301 * Otherwise, we need to reserve fragment header and
1302 * fragment alignment (= 8-15 octects, in total).
1303 *
1304 * Note that we may need to "move" the data from the tail of
1305 * of the buffer to the new fragment when we split
1306 * the message.
1307 *
1308 * FIXME: It may be fragmented into multiple chunks
1309 * at once if non-fragmentable extension headers
1310 * are too large.
1311 * --yoshfuji
1312 */
1313
1314 cork->length += length;
1315 if (length > mtu) {
1316 int proto = sk->sk_protocol;
1317 if (dontfrag && (proto == IPPROTO_UDP || proto == IPPROTO_RAW)){
1318 ipv6_local_rxpmtu(sk, fl6, mtu-exthdrlen);
1319 return -EMSGSIZE;
1320 }
1321
1322 if (proto == IPPROTO_UDP &&
1323 (rt->dst.dev->features & NETIF_F_UFO)) {
1324
1325 err = ip6_ufo_append_data(sk, getfrag, from, length,
1326 hh_len, fragheaderlen,
1327 transhdrlen, mtu, flags, rt);
1328 if (err)
1329 goto error;
1330 return 0;
1331 }
1332 }
1333
1334 if ((skb = skb_peek_tail(&sk->sk_write_queue)) == NULL)
1335 goto alloc_new_skb;
1336
1337 while (length > 0) {
1338 /* Check if the remaining data fits into current packet. */
1339 copy = (cork->length <= mtu && !(cork->flags & IPCORK_ALLFRAG) ? mtu : maxfraglen) - skb->len;
1340 if (copy < length)
1341 copy = maxfraglen - skb->len;
1342
1343 if (copy <= 0) {
1344 char *data;
1345 unsigned int datalen;
1346 unsigned int fraglen;
1347 unsigned int fraggap;
1348 unsigned int alloclen;
1349 struct sk_buff *skb_prev;
1350 alloc_new_skb:
1351 skb_prev = skb;
1352
1353 /* There's no room in the current skb */
1354 if (skb_prev)
1355 fraggap = skb_prev->len - maxfraglen;
1356 else
1357 fraggap = 0;
1358
1359 /*
1360 * If remaining data exceeds the mtu,
1361 * we know we need more fragment(s).
1362 */
1363 datalen = length + fraggap;
1364 if (datalen > (cork->length <= mtu && !(cork->flags & IPCORK_ALLFRAG) ? mtu : maxfraglen) - fragheaderlen)
1365 datalen = maxfraglen - fragheaderlen;
1366
1367 fraglen = datalen + fragheaderlen;
1368 if ((flags & MSG_MORE) &&
1369 !(rt->dst.dev->features&NETIF_F_SG))
1370 alloclen = mtu;
1371 else
1372 alloclen = datalen + fragheaderlen;
1373
1374 alloclen += dst_exthdrlen;
1375
1376 /*
1377 * The last fragment gets additional space at tail.
1378 * Note: we overallocate on fragments with MSG_MODE
1379 * because we have no idea if we're the last one.
1380 */
1381 if (datalen == length + fraggap)
1382 alloclen += rt->dst.trailer_len;
1383
1384 /*
1385 * We just reserve space for fragment header.
1386 * Note: this may be overallocation if the message
1387 * (without MSG_MORE) fits into the MTU.
1388 */
1389 alloclen += sizeof(struct frag_hdr);
1390
1391 if (transhdrlen) {
1392 skb = sock_alloc_send_skb(sk,
1393 alloclen + hh_len,
1394 (flags & MSG_DONTWAIT), &err);
1395 } else {
1396 skb = NULL;
1397 if (atomic_read(&sk->sk_wmem_alloc) <=
1398 2 * sk->sk_sndbuf)
1399 skb = sock_wmalloc(sk,
1400 alloclen + hh_len, 1,
1401 sk->sk_allocation);
1402 if (unlikely(skb == NULL))
1403 err = -ENOBUFS;
1404 else {
1405 /* Only the initial fragment
1406 * is time stamped.
1407 */
1408 tx_flags = 0;
1409 }
1410 }
1411 if (skb == NULL)
1412 goto error;
1413 /*
1414 * Fill in the control structures
1415 */
1416 skb->ip_summed = csummode;
1417 skb->csum = 0;
1418 /* reserve for fragmentation */
1419 skb_reserve(skb, hh_len+sizeof(struct frag_hdr));
1420
1421 if (sk->sk_type == SOCK_DGRAM)
1422 skb_shinfo(skb)->tx_flags = tx_flags;
1423
1424 /*
1425 * Find where to start putting bytes
1426 */
1427 data = skb_put(skb, fraglen + dst_exthdrlen);
1428 skb_set_network_header(skb, exthdrlen + dst_exthdrlen);
1429 data += fragheaderlen + dst_exthdrlen;
1430 skb->transport_header = (skb->network_header +
1431 fragheaderlen);
1432 if (fraggap) {
1433 skb->csum = skb_copy_and_csum_bits(
1434 skb_prev, maxfraglen,
1435 data + transhdrlen, fraggap, 0);
1436 skb_prev->csum = csum_sub(skb_prev->csum,
1437 skb->csum);
1438 data += fraggap;
1439 pskb_trim_unique(skb_prev, maxfraglen);
1440 }
1441 copy = datalen - transhdrlen - fraggap;
1442
1443 if (copy < 0) {
1444 err = -EINVAL;
1445 kfree_skb(skb);
1446 goto error;
1447 } else if (copy > 0 && getfrag(from, data + transhdrlen, offset, copy, fraggap, skb) < 0) {
1448 err = -EFAULT;
1449 kfree_skb(skb);
1450 goto error;
1451 }
1452
1453 offset += copy;
1454 length -= datalen - fraggap;
1455 transhdrlen = 0;
1456 exthdrlen = 0;
1457 dst_exthdrlen = 0;
1458 csummode = CHECKSUM_NONE;
1459
1460 /*
1461 * Put the packet on the pending queue
1462 */
1463 __skb_queue_tail(&sk->sk_write_queue, skb);
1464 continue;
1465 }
1466
1467 if (copy > length)
1468 copy = length;
1469
1470 if (!(rt->dst.dev->features&NETIF_F_SG)) {
1471 unsigned int off;
1472
1473 off = skb->len;
1474 if (getfrag(from, skb_put(skb, copy),
1475 offset, copy, off, skb) < 0) {
1476 __skb_trim(skb, off);
1477 err = -EFAULT;
1478 goto error;
1479 }
1480 } else {
1481 int i = skb_shinfo(skb)->nr_frags;
1482 skb_frag_t *frag = &skb_shinfo(skb)->frags[i-1];
1483 struct page *page = sk->sk_sndmsg_page;
1484 int off = sk->sk_sndmsg_off;
1485 unsigned int left;
1486
1487 if (page && (left = PAGE_SIZE - off) > 0) {
1488 if (copy >= left)
1489 copy = left;
1490 if (page != skb_frag_page(frag)) {
1491 if (i == MAX_SKB_FRAGS) {
1492 err = -EMSGSIZE;
1493 goto error;
1494 }
1495 skb_fill_page_desc(skb, i, page, sk->sk_sndmsg_off, 0);
1496 skb_frag_ref(skb, i);
1497 frag = &skb_shinfo(skb)->frags[i];
1498 }
1499 } else if(i < MAX_SKB_FRAGS) {
1500 if (copy > PAGE_SIZE)
1501 copy = PAGE_SIZE;
1502 page = alloc_pages(sk->sk_allocation, 0);
1503 if (page == NULL) {
1504 err = -ENOMEM;
1505 goto error;
1506 }
1507 sk->sk_sndmsg_page = page;
1508 sk->sk_sndmsg_off = 0;
1509
1510 skb_fill_page_desc(skb, i, page, 0, 0);
1511 frag = &skb_shinfo(skb)->frags[i];
1512 } else {
1513 err = -EMSGSIZE;
1514 goto error;
1515 }
1516 if (getfrag(from,
1517 skb_frag_address(frag) + skb_frag_size(frag),
1518 offset, copy, skb->len, skb) < 0) {
1519 err = -EFAULT;
1520 goto error;
1521 }
1522 sk->sk_sndmsg_off += copy;
1523 skb_frag_size_add(frag, copy);
1524 skb->len += copy;
1525 skb->data_len += copy;
1526 skb->truesize += copy;
1527 atomic_add(copy, &sk->sk_wmem_alloc);
1528 }
1529 offset += copy;
1530 length -= copy;
1531 }
1532 return 0;
1533 error:
1534 cork->length -= length;
1535 IP6_INC_STATS(sock_net(sk), rt->rt6i_idev, IPSTATS_MIB_OUTDISCARDS);
1536 return err;
1537 }
1538
1539 static void ip6_cork_release(struct inet_sock *inet, struct ipv6_pinfo *np)
1540 {
1541 if (np->cork.opt) {
1542 kfree(np->cork.opt->dst0opt);
1543 kfree(np->cork.opt->dst1opt);
1544 kfree(np->cork.opt->hopopt);
1545 kfree(np->cork.opt->srcrt);
1546 kfree(np->cork.opt);
1547 np->cork.opt = NULL;
1548 }
1549
1550 if (inet->cork.base.dst) {
1551 dst_release(inet->cork.base.dst);
1552 inet->cork.base.dst = NULL;
1553 inet->cork.base.flags &= ~IPCORK_ALLFRAG;
1554 }
1555 memset(&inet->cork.fl, 0, sizeof(inet->cork.fl));
1556 }
1557
1558 int ip6_push_pending_frames(struct sock *sk)
1559 {
1560 struct sk_buff *skb, *tmp_skb;
1561 struct sk_buff **tail_skb;
1562 struct in6_addr final_dst_buf, *final_dst = &final_dst_buf;
1563 struct inet_sock *inet = inet_sk(sk);
1564 struct ipv6_pinfo *np = inet6_sk(sk);
1565 struct net *net = sock_net(sk);
1566 struct ipv6hdr *hdr;
1567 struct ipv6_txoptions *opt = np->cork.opt;
1568 struct rt6_info *rt = (struct rt6_info *)inet->cork.base.dst;
1569 struct flowi6 *fl6 = &inet->cork.fl.u.ip6;
1570 unsigned char proto = fl6->flowi6_proto;
1571 int err = 0;
1572
1573 if ((skb = __skb_dequeue(&sk->sk_write_queue)) == NULL)
1574 goto out;
1575 tail_skb = &(skb_shinfo(skb)->frag_list);
1576
1577 /* move skb->data to ip header from ext header */
1578 if (skb->data < skb_network_header(skb))
1579 __skb_pull(skb, skb_network_offset(skb));
1580 while ((tmp_skb = __skb_dequeue(&sk->sk_write_queue)) != NULL) {
1581 __skb_pull(tmp_skb, skb_network_header_len(skb));
1582 *tail_skb = tmp_skb;
1583 tail_skb = &(tmp_skb->next);
1584 skb->len += tmp_skb->len;
1585 skb->data_len += tmp_skb->len;
1586 skb->truesize += tmp_skb->truesize;
1587 tmp_skb->destructor = NULL;
1588 tmp_skb->sk = NULL;
1589 }
1590
1591 /* Allow local fragmentation. */
1592 if (np->pmtudisc < IPV6_PMTUDISC_DO)
1593 skb->local_df = 1;
1594
1595 *final_dst = fl6->daddr;
1596 __skb_pull(skb, skb_network_header_len(skb));
1597 if (opt && opt->opt_flen)
1598 ipv6_push_frag_opts(skb, opt, &proto);
1599 if (opt && opt->opt_nflen)
1600 ipv6_push_nfrag_opts(skb, opt, &proto, &final_dst);
1601
1602 skb_push(skb, sizeof(struct ipv6hdr));
1603 skb_reset_network_header(skb);
1604 hdr = ipv6_hdr(skb);
1605
1606 *(__be32*)hdr = fl6->flowlabel |
1607 htonl(0x60000000 | ((int)np->cork.tclass << 20));
1608
1609 hdr->hop_limit = np->cork.hop_limit;
1610 hdr->nexthdr = proto;
1611 hdr->saddr = fl6->saddr;
1612 hdr->daddr = *final_dst;
1613
1614 skb->priority = sk->sk_priority;
1615 skb->mark = sk->sk_mark;
1616
1617 skb_dst_set(skb, dst_clone(&rt->dst));
1618 IP6_UPD_PO_STATS(net, rt->rt6i_idev, IPSTATS_MIB_OUT, skb->len);
1619 if (proto == IPPROTO_ICMPV6) {
1620 struct inet6_dev *idev = ip6_dst_idev(skb_dst(skb));
1621
1622 ICMP6MSGOUT_INC_STATS_BH(net, idev, icmp6_hdr(skb)->icmp6_type);
1623 ICMP6_INC_STATS_BH(net, idev, ICMP6_MIB_OUTMSGS);
1624 }
1625
1626 err = ip6_local_out(skb);
1627 if (err) {
1628 if (err > 0)
1629 err = net_xmit_errno(err);
1630 if (err)
1631 goto error;
1632 }
1633
1634 out:
1635 ip6_cork_release(inet, np);
1636 return err;
1637 error:
1638 IP6_INC_STATS(net, rt->rt6i_idev, IPSTATS_MIB_OUTDISCARDS);
1639 goto out;
1640 }
1641
1642 void ip6_flush_pending_frames(struct sock *sk)
1643 {
1644 struct sk_buff *skb;
1645
1646 while ((skb = __skb_dequeue_tail(&sk->sk_write_queue)) != NULL) {
1647 if (skb_dst(skb))
1648 IP6_INC_STATS(sock_net(sk), ip6_dst_idev(skb_dst(skb)),
1649 IPSTATS_MIB_OUTDISCARDS);
1650 kfree_skb(skb);
1651 }
1652
1653 ip6_cork_release(inet_sk(sk), inet6_sk(sk));
1654 }
kernel source for telekom puls (alcatel/mediatek)