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Commit | Line | Data |
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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 | static int ip6_finish_output2(struct sock *sk, struct sk_buff *skb) | |
60 | { | |
61 | struct dst_entry *dst = skb_dst(skb); | |
62 | struct net_device *dev = dst->dev; | |
63 | struct neighbour *neigh; | |
64 | struct in6_addr *nexthop; | |
65 | int ret; | |
66 | ||
67 | skb->protocol = htons(ETH_P_IPV6); | |
68 | skb->dev = dev; | |
69 | ||
70 | if (ipv6_addr_is_multicast(&ipv6_hdr(skb)->daddr)) { | |
71 | struct inet6_dev *idev = ip6_dst_idev(skb_dst(skb)); | |
72 | ||
73 | if (!(dev->flags & IFF_LOOPBACK) && sk_mc_loop(sk) && | |
74 | ((mroute6_socket(dev_net(dev), skb) && | |
75 | !(IP6CB(skb)->flags & IP6SKB_FORWARDED)) || | |
76 | ipv6_chk_mcast_addr(dev, &ipv6_hdr(skb)->daddr, | |
77 | &ipv6_hdr(skb)->saddr))) { | |
78 | struct sk_buff *newskb = skb_clone(skb, GFP_ATOMIC); | |
79 | ||
80 | /* Do not check for IFF_ALLMULTI; multicast routing | |
81 | is not supported in any case. | |
82 | */ | |
83 | if (newskb) | |
84 | NF_HOOK(NFPROTO_IPV6, NF_INET_POST_ROUTING, | |
85 | sk, newskb, NULL, newskb->dev, | |
86 | dev_loopback_xmit); | |
87 | ||
88 | if (ipv6_hdr(skb)->hop_limit == 0) { | |
89 | IP6_INC_STATS(dev_net(dev), idev, | |
90 | IPSTATS_MIB_OUTDISCARDS); | |
91 | kfree_skb(skb); | |
92 | return 0; | |
93 | } | |
94 | } | |
95 | ||
96 | IP6_UPD_PO_STATS(dev_net(dev), idev, IPSTATS_MIB_OUTMCAST, | |
97 | skb->len); | |
98 | ||
99 | if (IPV6_ADDR_MC_SCOPE(&ipv6_hdr(skb)->daddr) <= | |
100 | IPV6_ADDR_SCOPE_NODELOCAL && | |
101 | !(dev->flags & IFF_LOOPBACK)) { | |
102 | kfree_skb(skb); | |
103 | return 0; | |
104 | } | |
105 | } | |
106 | ||
107 | rcu_read_lock_bh(); | |
108 | nexthop = rt6_nexthop((struct rt6_info *)dst); | |
109 | neigh = __ipv6_neigh_lookup_noref(dst->dev, nexthop); | |
110 | if (unlikely(!neigh)) | |
111 | neigh = __neigh_create(&nd_tbl, nexthop, dst->dev, false); | |
112 | if (!IS_ERR(neigh)) { | |
113 | ret = dst_neigh_output(dst, neigh, skb); | |
114 | rcu_read_unlock_bh(); | |
115 | return ret; | |
116 | } | |
117 | rcu_read_unlock_bh(); | |
118 | ||
119 | IP6_INC_STATS(dev_net(dst->dev), | |
120 | ip6_dst_idev(dst), IPSTATS_MIB_OUTNOROUTES); | |
121 | kfree_skb(skb); | |
122 | return -EINVAL; | |
123 | } | |
124 | ||
125 | static int ip6_finish_output(struct sock *sk, struct sk_buff *skb) | |
126 | { | |
127 | if ((skb->len > ip6_skb_dst_mtu(skb) && !skb_is_gso(skb)) || | |
128 | dst_allfrag(skb_dst(skb)) || | |
129 | (IP6CB(skb)->frag_max_size && skb->len > IP6CB(skb)->frag_max_size)) | |
130 | return ip6_fragment(sk, skb, ip6_finish_output2); | |
131 | else | |
132 | return ip6_finish_output2(sk, skb); | |
133 | } | |
134 | ||
135 | int ip6_output(struct sock *sk, struct sk_buff *skb) | |
136 | { | |
137 | struct net_device *dev = skb_dst(skb)->dev; | |
138 | struct inet6_dev *idev = ip6_dst_idev(skb_dst(skb)); | |
139 | if (unlikely(idev->cnf.disable_ipv6)) { | |
140 | IP6_INC_STATS(dev_net(dev), idev, | |
141 | IPSTATS_MIB_OUTDISCARDS); | |
142 | kfree_skb(skb); | |
143 | return 0; | |
144 | } | |
145 | ||
146 | return NF_HOOK_COND(NFPROTO_IPV6, NF_INET_POST_ROUTING, sk, skb, | |
147 | NULL, dev, | |
148 | ip6_finish_output, | |
149 | !(IP6CB(skb)->flags & IP6SKB_REROUTED)); | |
150 | } | |
151 | ||
152 | /* | |
153 | * xmit an sk_buff (used by TCP, SCTP and DCCP) | |
154 | */ | |
155 | ||
156 | int ip6_xmit(struct sock *sk, struct sk_buff *skb, struct flowi6 *fl6, | |
157 | struct ipv6_txoptions *opt, int tclass) | |
158 | { | |
159 | struct net *net = sock_net(sk); | |
160 | struct ipv6_pinfo *np = inet6_sk(sk); | |
161 | struct in6_addr *first_hop = &fl6->daddr; | |
162 | struct dst_entry *dst = skb_dst(skb); | |
163 | struct ipv6hdr *hdr; | |
164 | u8 proto = fl6->flowi6_proto; | |
165 | int seg_len = skb->len; | |
166 | int hlimit = -1; | |
167 | u32 mtu; | |
168 | ||
169 | if (opt) { | |
170 | unsigned int head_room; | |
171 | ||
172 | /* First: exthdrs may take lots of space (~8K for now) | |
173 | MAX_HEADER is not enough. | |
174 | */ | |
175 | head_room = opt->opt_nflen + opt->opt_flen; | |
176 | seg_len += head_room; | |
177 | head_room += sizeof(struct ipv6hdr) + LL_RESERVED_SPACE(dst->dev); | |
178 | ||
179 | if (skb_headroom(skb) < head_room) { | |
180 | struct sk_buff *skb2 = skb_realloc_headroom(skb, head_room); | |
181 | if (!skb2) { | |
182 | IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)), | |
183 | IPSTATS_MIB_OUTDISCARDS); | |
184 | kfree_skb(skb); | |
185 | return -ENOBUFS; | |
186 | } | |
187 | consume_skb(skb); | |
188 | skb = skb2; | |
189 | skb_set_owner_w(skb, sk); | |
190 | } | |
191 | if (opt->opt_flen) | |
192 | ipv6_push_frag_opts(skb, opt, &proto); | |
193 | if (opt->opt_nflen) | |
194 | ipv6_push_nfrag_opts(skb, opt, &proto, &first_hop); | |
195 | } | |
196 | ||
197 | skb_push(skb, sizeof(struct ipv6hdr)); | |
198 | skb_reset_network_header(skb); | |
199 | hdr = ipv6_hdr(skb); | |
200 | ||
201 | /* | |
202 | * Fill in the IPv6 header | |
203 | */ | |
204 | if (np) | |
205 | hlimit = np->hop_limit; | |
206 | if (hlimit < 0) | |
207 | hlimit = ip6_dst_hoplimit(dst); | |
208 | ||
209 | ip6_flow_hdr(hdr, tclass, ip6_make_flowlabel(net, skb, fl6->flowlabel, | |
210 | np->autoflowlabel)); | |
211 | ||
212 | hdr->payload_len = htons(seg_len); | |
213 | hdr->nexthdr = proto; | |
214 | hdr->hop_limit = hlimit; | |
215 | ||
216 | hdr->saddr = fl6->saddr; | |
217 | hdr->daddr = *first_hop; | |
218 | ||
219 | skb->protocol = htons(ETH_P_IPV6); | |
220 | skb->priority = sk->sk_priority; | |
221 | skb->mark = sk->sk_mark; | |
222 | ||
223 | mtu = dst_mtu(dst); | |
224 | if ((skb->len <= mtu) || skb->ignore_df || skb_is_gso(skb)) { | |
225 | IP6_UPD_PO_STATS(net, ip6_dst_idev(skb_dst(skb)), | |
226 | IPSTATS_MIB_OUT, skb->len); | |
227 | return NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_OUT, sk, skb, | |
228 | NULL, dst->dev, dst_output_sk); | |
229 | } | |
230 | ||
231 | skb->dev = dst->dev; | |
232 | ipv6_local_error(sk, EMSGSIZE, fl6, mtu); | |
233 | IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)), IPSTATS_MIB_FRAGFAILS); | |
234 | kfree_skb(skb); | |
235 | return -EMSGSIZE; | |
236 | } | |
237 | EXPORT_SYMBOL(ip6_xmit); | |
238 | ||
239 | static int ip6_call_ra_chain(struct sk_buff *skb, int sel) | |
240 | { | |
241 | struct ip6_ra_chain *ra; | |
242 | struct sock *last = NULL; | |
243 | ||
244 | read_lock(&ip6_ra_lock); | |
245 | for (ra = ip6_ra_chain; ra; ra = ra->next) { | |
246 | struct sock *sk = ra->sk; | |
247 | if (sk && ra->sel == sel && | |
248 | (!sk->sk_bound_dev_if || | |
249 | sk->sk_bound_dev_if == skb->dev->ifindex)) { | |
250 | if (last) { | |
251 | struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC); | |
252 | if (skb2) | |
253 | rawv6_rcv(last, skb2); | |
254 | } | |
255 | last = sk; | |
256 | } | |
257 | } | |
258 | ||
259 | if (last) { | |
260 | rawv6_rcv(last, skb); | |
261 | read_unlock(&ip6_ra_lock); | |
262 | return 1; | |
263 | } | |
264 | read_unlock(&ip6_ra_lock); | |
265 | return 0; | |
266 | } | |
267 | ||
268 | static int ip6_forward_proxy_check(struct sk_buff *skb) | |
269 | { | |
270 | struct ipv6hdr *hdr = ipv6_hdr(skb); | |
271 | u8 nexthdr = hdr->nexthdr; | |
272 | __be16 frag_off; | |
273 | int offset; | |
274 | ||
275 | if (ipv6_ext_hdr(nexthdr)) { | |
276 | offset = ipv6_skip_exthdr(skb, sizeof(*hdr), &nexthdr, &frag_off); | |
277 | if (offset < 0) | |
278 | return 0; | |
279 | } else | |
280 | offset = sizeof(struct ipv6hdr); | |
281 | ||
282 | if (nexthdr == IPPROTO_ICMPV6) { | |
283 | struct icmp6hdr *icmp6; | |
284 | ||
285 | if (!pskb_may_pull(skb, (skb_network_header(skb) + | |
286 | offset + 1 - skb->data))) | |
287 | return 0; | |
288 | ||
289 | icmp6 = (struct icmp6hdr *)(skb_network_header(skb) + offset); | |
290 | ||
291 | switch (icmp6->icmp6_type) { | |
292 | case NDISC_ROUTER_SOLICITATION: | |
293 | case NDISC_ROUTER_ADVERTISEMENT: | |
294 | case NDISC_NEIGHBOUR_SOLICITATION: | |
295 | case NDISC_NEIGHBOUR_ADVERTISEMENT: | |
296 | case NDISC_REDIRECT: | |
297 | /* For reaction involving unicast neighbor discovery | |
298 | * message destined to the proxied address, pass it to | |
299 | * input function. | |
300 | */ | |
301 | return 1; | |
302 | default: | |
303 | break; | |
304 | } | |
305 | } | |
306 | ||
307 | /* | |
308 | * The proxying router can't forward traffic sent to a link-local | |
309 | * address, so signal the sender and discard the packet. This | |
310 | * behavior is clarified by the MIPv6 specification. | |
311 | */ | |
312 | if (ipv6_addr_type(&hdr->daddr) & IPV6_ADDR_LINKLOCAL) { | |
313 | dst_link_failure(skb); | |
314 | return -1; | |
315 | } | |
316 | ||
317 | return 0; | |
318 | } | |
319 | ||
320 | static inline int ip6_forward_finish(struct sock *sk, struct sk_buff *skb) | |
321 | { | |
322 | skb_sender_cpu_clear(skb); | |
323 | return dst_output_sk(sk, skb); | |
324 | } | |
325 | ||
326 | static unsigned int ip6_dst_mtu_forward(const struct dst_entry *dst) | |
327 | { | |
328 | unsigned int mtu; | |
329 | struct inet6_dev *idev; | |
330 | ||
331 | if (dst_metric_locked(dst, RTAX_MTU)) { | |
332 | mtu = dst_metric_raw(dst, RTAX_MTU); | |
333 | if (mtu) | |
334 | return mtu; | |
335 | } | |
336 | ||
337 | mtu = IPV6_MIN_MTU; | |
338 | rcu_read_lock(); | |
339 | idev = __in6_dev_get(dst->dev); | |
340 | if (idev) | |
341 | mtu = idev->cnf.mtu6; | |
342 | rcu_read_unlock(); | |
343 | ||
344 | return mtu; | |
345 | } | |
346 | ||
347 | static bool ip6_pkt_too_big(const struct sk_buff *skb, unsigned int mtu) | |
348 | { | |
349 | if (skb->len <= mtu) | |
350 | return false; | |
351 | ||
352 | /* ipv6 conntrack defrag sets max_frag_size + ignore_df */ | |
353 | if (IP6CB(skb)->frag_max_size && IP6CB(skb)->frag_max_size > mtu) | |
354 | return true; | |
355 | ||
356 | if (skb->ignore_df) | |
357 | return false; | |
358 | ||
359 | if (skb_is_gso(skb) && skb_gso_network_seglen(skb) <= mtu) | |
360 | return false; | |
361 | ||
362 | return true; | |
363 | } | |
364 | ||
365 | int ip6_forward(struct sk_buff *skb) | |
366 | { | |
367 | struct dst_entry *dst = skb_dst(skb); | |
368 | struct ipv6hdr *hdr = ipv6_hdr(skb); | |
369 | struct inet6_skb_parm *opt = IP6CB(skb); | |
370 | struct net *net = dev_net(dst->dev); | |
371 | u32 mtu; | |
372 | ||
373 | if (net->ipv6.devconf_all->forwarding == 0) | |
374 | goto error; | |
375 | ||
376 | if (skb->pkt_type != PACKET_HOST) | |
377 | goto drop; | |
378 | ||
379 | if (skb_warn_if_lro(skb)) | |
380 | goto drop; | |
381 | ||
382 | if (!xfrm6_policy_check(NULL, XFRM_POLICY_FWD, skb)) { | |
383 | IP6_INC_STATS_BH(net, ip6_dst_idev(dst), | |
384 | IPSTATS_MIB_INDISCARDS); | |
385 | goto drop; | |
386 | } | |
387 | ||
388 | skb_forward_csum(skb); | |
389 | ||
390 | /* | |
391 | * We DO NOT make any processing on | |
392 | * RA packets, pushing them to user level AS IS | |
393 | * without ane WARRANTY that application will be able | |
394 | * to interpret them. The reason is that we | |
395 | * cannot make anything clever here. | |
396 | * | |
397 | * We are not end-node, so that if packet contains | |
398 | * AH/ESP, we cannot make anything. | |
399 | * Defragmentation also would be mistake, RA packets | |
400 | * cannot be fragmented, because there is no warranty | |
401 | * that different fragments will go along one path. --ANK | |
402 | */ | |
403 | if (unlikely(opt->flags & IP6SKB_ROUTERALERT)) { | |
404 | if (ip6_call_ra_chain(skb, ntohs(opt->ra))) | |
405 | return 0; | |
406 | } | |
407 | ||
408 | /* | |
409 | * check and decrement ttl | |
410 | */ | |
411 | if (hdr->hop_limit <= 1) { | |
412 | /* Force OUTPUT device used as source address */ | |
413 | skb->dev = dst->dev; | |
414 | icmpv6_send(skb, ICMPV6_TIME_EXCEED, ICMPV6_EXC_HOPLIMIT, 0); | |
415 | IP6_INC_STATS_BH(net, ip6_dst_idev(dst), | |
416 | IPSTATS_MIB_INHDRERRORS); | |
417 | ||
418 | kfree_skb(skb); | |
419 | return -ETIMEDOUT; | |
420 | } | |
421 | ||
422 | /* XXX: idev->cnf.proxy_ndp? */ | |
423 | if (net->ipv6.devconf_all->proxy_ndp && | |
424 | pneigh_lookup(&nd_tbl, net, &hdr->daddr, skb->dev, 0)) { | |
425 | int proxied = ip6_forward_proxy_check(skb); | |
426 | if (proxied > 0) | |
427 | return ip6_input(skb); | |
428 | else if (proxied < 0) { | |
429 | IP6_INC_STATS_BH(net, ip6_dst_idev(dst), | |
430 | IPSTATS_MIB_INDISCARDS); | |
431 | goto drop; | |
432 | } | |
433 | } | |
434 | ||
435 | if (!xfrm6_route_forward(skb)) { | |
436 | IP6_INC_STATS_BH(net, ip6_dst_idev(dst), | |
437 | IPSTATS_MIB_INDISCARDS); | |
438 | goto drop; | |
439 | } | |
440 | dst = skb_dst(skb); | |
441 | ||
442 | /* IPv6 specs say nothing about it, but it is clear that we cannot | |
443 | send redirects to source routed frames. | |
444 | We don't send redirects to frames decapsulated from IPsec. | |
445 | */ | |
446 | if (skb->dev == dst->dev && opt->srcrt == 0 && !skb_sec_path(skb)) { | |
447 | struct in6_addr *target = NULL; | |
448 | struct inet_peer *peer; | |
449 | struct rt6_info *rt; | |
450 | ||
451 | /* | |
452 | * incoming and outgoing devices are the same | |
453 | * send a redirect. | |
454 | */ | |
455 | ||
456 | rt = (struct rt6_info *) dst; | |
457 | if (rt->rt6i_flags & RTF_GATEWAY) | |
458 | target = &rt->rt6i_gateway; | |
459 | else | |
460 | target = &hdr->daddr; | |
461 | ||
462 | peer = inet_getpeer_v6(net->ipv6.peers, &rt->rt6i_dst.addr, 1); | |
463 | ||
464 | /* Limit redirects both by destination (here) | |
465 | and by source (inside ndisc_send_redirect) | |
466 | */ | |
467 | if (inet_peer_xrlim_allow(peer, 1*HZ)) | |
468 | ndisc_send_redirect(skb, target); | |
469 | if (peer) | |
470 | inet_putpeer(peer); | |
471 | } else { | |
472 | int addrtype = ipv6_addr_type(&hdr->saddr); | |
473 | ||
474 | /* This check is security critical. */ | |
475 | if (addrtype == IPV6_ADDR_ANY || | |
476 | addrtype & (IPV6_ADDR_MULTICAST | IPV6_ADDR_LOOPBACK)) | |
477 | goto error; | |
478 | if (addrtype & IPV6_ADDR_LINKLOCAL) { | |
479 | icmpv6_send(skb, ICMPV6_DEST_UNREACH, | |
480 | ICMPV6_NOT_NEIGHBOUR, 0); | |
481 | goto error; | |
482 | } | |
483 | } | |
484 | ||
485 | mtu = ip6_dst_mtu_forward(dst); | |
486 | if (mtu < IPV6_MIN_MTU) | |
487 | mtu = IPV6_MIN_MTU; | |
488 | ||
489 | if (ip6_pkt_too_big(skb, mtu)) { | |
490 | /* Again, force OUTPUT device used as source address */ | |
491 | skb->dev = dst->dev; | |
492 | icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu); | |
493 | IP6_INC_STATS_BH(net, ip6_dst_idev(dst), | |
494 | IPSTATS_MIB_INTOOBIGERRORS); | |
495 | IP6_INC_STATS_BH(net, ip6_dst_idev(dst), | |
496 | IPSTATS_MIB_FRAGFAILS); | |
497 | kfree_skb(skb); | |
498 | return -EMSGSIZE; | |
499 | } | |
500 | ||
501 | if (skb_cow(skb, dst->dev->hard_header_len)) { | |
502 | IP6_INC_STATS_BH(net, ip6_dst_idev(dst), | |
503 | IPSTATS_MIB_OUTDISCARDS); | |
504 | goto drop; | |
505 | } | |
506 | ||
507 | hdr = ipv6_hdr(skb); | |
508 | ||
509 | /* Mangling hops number delayed to point after skb COW */ | |
510 | ||
511 | hdr->hop_limit--; | |
512 | ||
513 | IP6_INC_STATS_BH(net, ip6_dst_idev(dst), IPSTATS_MIB_OUTFORWDATAGRAMS); | |
514 | IP6_ADD_STATS_BH(net, ip6_dst_idev(dst), IPSTATS_MIB_OUTOCTETS, skb->len); | |
515 | return NF_HOOK(NFPROTO_IPV6, NF_INET_FORWARD, NULL, skb, | |
516 | skb->dev, dst->dev, | |
517 | ip6_forward_finish); | |
518 | ||
519 | error: | |
520 | IP6_INC_STATS_BH(net, ip6_dst_idev(dst), IPSTATS_MIB_INADDRERRORS); | |
521 | drop: | |
522 | kfree_skb(skb); | |
523 | return -EINVAL; | |
524 | } | |
525 | ||
526 | static void ip6_copy_metadata(struct sk_buff *to, struct sk_buff *from) | |
527 | { | |
528 | to->pkt_type = from->pkt_type; | |
529 | to->priority = from->priority; | |
530 | to->protocol = from->protocol; | |
531 | skb_dst_drop(to); | |
532 | skb_dst_set(to, dst_clone(skb_dst(from))); | |
533 | to->dev = from->dev; | |
534 | to->mark = from->mark; | |
535 | ||
536 | #ifdef CONFIG_NET_SCHED | |
537 | to->tc_index = from->tc_index; | |
538 | #endif | |
539 | nf_copy(to, from); | |
540 | skb_copy_secmark(to, from); | |
541 | } | |
542 | ||
543 | int ip6_fragment(struct sock *sk, struct sk_buff *skb, | |
544 | int (*output)(struct sock *, struct sk_buff *)) | |
545 | { | |
546 | struct sk_buff *frag; | |
547 | struct rt6_info *rt = (struct rt6_info *)skb_dst(skb); | |
548 | struct ipv6_pinfo *np = skb->sk && !dev_recursion_level() ? | |
549 | inet6_sk(skb->sk) : NULL; | |
550 | struct ipv6hdr *tmp_hdr; | |
551 | struct frag_hdr *fh; | |
552 | unsigned int mtu, hlen, left, len; | |
553 | int hroom, troom; | |
554 | __be32 frag_id = 0; | |
555 | int ptr, offset = 0, err = 0; | |
556 | u8 *prevhdr, nexthdr = 0; | |
557 | struct net *net = dev_net(skb_dst(skb)->dev); | |
558 | ||
559 | hlen = ip6_find_1stfragopt(skb, &prevhdr); | |
560 | nexthdr = *prevhdr; | |
561 | ||
562 | mtu = ip6_skb_dst_mtu(skb); | |
563 | ||
564 | /* We must not fragment if the socket is set to force MTU discovery | |
565 | * or if the skb it not generated by a local socket. | |
566 | */ | |
567 | if (unlikely(!skb->ignore_df && skb->len > mtu) || | |
568 | (IP6CB(skb)->frag_max_size && | |
569 | IP6CB(skb)->frag_max_size > mtu)) { | |
570 | if (skb->sk && dst_allfrag(skb_dst(skb))) | |
571 | sk_nocaps_add(skb->sk, NETIF_F_GSO_MASK); | |
572 | ||
573 | skb->dev = skb_dst(skb)->dev; | |
574 | icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu); | |
575 | IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)), | |
576 | IPSTATS_MIB_FRAGFAILS); | |
577 | kfree_skb(skb); | |
578 | return -EMSGSIZE; | |
579 | } | |
580 | ||
581 | if (np && np->frag_size < mtu) { | |
582 | if (np->frag_size) | |
583 | mtu = np->frag_size; | |
584 | } | |
585 | mtu -= hlen + sizeof(struct frag_hdr); | |
586 | ||
587 | if (skb_has_frag_list(skb)) { | |
588 | int first_len = skb_pagelen(skb); | |
589 | struct sk_buff *frag2; | |
590 | ||
591 | if (first_len - hlen > mtu || | |
592 | ((first_len - hlen) & 7) || | |
593 | skb_cloned(skb)) | |
594 | goto slow_path; | |
595 | ||
596 | skb_walk_frags(skb, frag) { | |
597 | /* Correct geometry. */ | |
598 | if (frag->len > mtu || | |
599 | ((frag->len & 7) && frag->next) || | |
600 | skb_headroom(frag) < hlen) | |
601 | goto slow_path_clean; | |
602 | ||
603 | /* Partially cloned skb? */ | |
604 | if (skb_shared(frag)) | |
605 | goto slow_path_clean; | |
606 | ||
607 | BUG_ON(frag->sk); | |
608 | if (skb->sk) { | |
609 | frag->sk = skb->sk; | |
610 | frag->destructor = sock_wfree; | |
611 | } | |
612 | skb->truesize -= frag->truesize; | |
613 | } | |
614 | ||
615 | err = 0; | |
616 | offset = 0; | |
617 | frag = skb_shinfo(skb)->frag_list; | |
618 | skb_frag_list_init(skb); | |
619 | /* BUILD HEADER */ | |
620 | ||
621 | *prevhdr = NEXTHDR_FRAGMENT; | |
622 | tmp_hdr = kmemdup(skb_network_header(skb), hlen, GFP_ATOMIC); | |
623 | if (!tmp_hdr) { | |
624 | IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)), | |
625 | IPSTATS_MIB_FRAGFAILS); | |
626 | return -ENOMEM; | |
627 | } | |
628 | ||
629 | __skb_pull(skb, hlen); | |
630 | fh = (struct frag_hdr *)__skb_push(skb, sizeof(struct frag_hdr)); | |
631 | __skb_push(skb, hlen); | |
632 | skb_reset_network_header(skb); | |
633 | memcpy(skb_network_header(skb), tmp_hdr, hlen); | |
634 | ||
635 | ipv6_select_ident(net, fh, rt); | |
636 | fh->nexthdr = nexthdr; | |
637 | fh->reserved = 0; | |
638 | fh->frag_off = htons(IP6_MF); | |
639 | frag_id = fh->identification; | |
640 | ||
641 | first_len = skb_pagelen(skb); | |
642 | skb->data_len = first_len - skb_headlen(skb); | |
643 | skb->len = first_len; | |
644 | ipv6_hdr(skb)->payload_len = htons(first_len - | |
645 | sizeof(struct ipv6hdr)); | |
646 | ||
647 | dst_hold(&rt->dst); | |
648 | ||
649 | for (;;) { | |
650 | /* Prepare header of the next frame, | |
651 | * before previous one went down. */ | |
652 | if (frag) { | |
653 | frag->ip_summed = CHECKSUM_NONE; | |
654 | skb_reset_transport_header(frag); | |
655 | fh = (struct frag_hdr *)__skb_push(frag, sizeof(struct frag_hdr)); | |
656 | __skb_push(frag, hlen); | |
657 | skb_reset_network_header(frag); | |
658 | memcpy(skb_network_header(frag), tmp_hdr, | |
659 | hlen); | |
660 | offset += skb->len - hlen - sizeof(struct frag_hdr); | |
661 | fh->nexthdr = nexthdr; | |
662 | fh->reserved = 0; | |
663 | fh->frag_off = htons(offset); | |
664 | if (frag->next) | |
665 | fh->frag_off |= htons(IP6_MF); | |
666 | fh->identification = frag_id; | |
667 | ipv6_hdr(frag)->payload_len = | |
668 | htons(frag->len - | |
669 | sizeof(struct ipv6hdr)); | |
670 | ip6_copy_metadata(frag, skb); | |
671 | } | |
672 | ||
673 | err = output(sk, skb); | |
674 | if (!err) | |
675 | IP6_INC_STATS(net, ip6_dst_idev(&rt->dst), | |
676 | IPSTATS_MIB_FRAGCREATES); | |
677 | ||
678 | if (err || !frag) | |
679 | break; | |
680 | ||
681 | skb = frag; | |
682 | frag = skb->next; | |
683 | skb->next = NULL; | |
684 | } | |
685 | ||
686 | kfree(tmp_hdr); | |
687 | ||
688 | if (err == 0) { | |
689 | IP6_INC_STATS(net, ip6_dst_idev(&rt->dst), | |
690 | IPSTATS_MIB_FRAGOKS); | |
691 | ip6_rt_put(rt); | |
692 | return 0; | |
693 | } | |
694 | ||
695 | kfree_skb_list(frag); | |
696 | ||
697 | IP6_INC_STATS(net, ip6_dst_idev(&rt->dst), | |
698 | IPSTATS_MIB_FRAGFAILS); | |
699 | ip6_rt_put(rt); | |
700 | return err; | |
701 | ||
702 | slow_path_clean: | |
703 | skb_walk_frags(skb, frag2) { | |
704 | if (frag2 == frag) | |
705 | break; | |
706 | frag2->sk = NULL; | |
707 | frag2->destructor = NULL; | |
708 | skb->truesize += frag2->truesize; | |
709 | } | |
710 | } | |
711 | ||
712 | slow_path: | |
713 | if ((skb->ip_summed == CHECKSUM_PARTIAL) && | |
714 | skb_checksum_help(skb)) | |
715 | goto fail; | |
716 | ||
717 | left = skb->len - hlen; /* Space per frame */ | |
718 | ptr = hlen; /* Where to start from */ | |
719 | ||
720 | /* | |
721 | * Fragment the datagram. | |
722 | */ | |
723 | ||
724 | *prevhdr = NEXTHDR_FRAGMENT; | |
725 | hroom = LL_RESERVED_SPACE(rt->dst.dev); | |
726 | troom = rt->dst.dev->needed_tailroom; | |
727 | ||
728 | /* | |
729 | * Keep copying data until we run out. | |
730 | */ | |
731 | while (left > 0) { | |
732 | len = left; | |
733 | /* IF: it doesn't fit, use 'mtu' - the data space left */ | |
734 | if (len > mtu) | |
735 | len = mtu; | |
736 | /* IF: we are not sending up to and including the packet end | |
737 | then align the next start on an eight byte boundary */ | |
738 | if (len < left) { | |
739 | len &= ~7; | |
740 | } | |
741 | ||
742 | /* Allocate buffer */ | |
743 | frag = alloc_skb(len + hlen + sizeof(struct frag_hdr) + | |
744 | hroom + troom, GFP_ATOMIC); | |
745 | if (!frag) { | |
746 | IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)), | |
747 | IPSTATS_MIB_FRAGFAILS); | |
748 | err = -ENOMEM; | |
749 | goto fail; | |
750 | } | |
751 | ||
752 | /* | |
753 | * Set up data on packet | |
754 | */ | |
755 | ||
756 | ip6_copy_metadata(frag, skb); | |
757 | skb_reserve(frag, hroom); | |
758 | skb_put(frag, len + hlen + sizeof(struct frag_hdr)); | |
759 | skb_reset_network_header(frag); | |
760 | fh = (struct frag_hdr *)(skb_network_header(frag) + hlen); | |
761 | frag->transport_header = (frag->network_header + hlen + | |
762 | sizeof(struct frag_hdr)); | |
763 | ||
764 | /* | |
765 | * Charge the memory for the fragment to any owner | |
766 | * it might possess | |
767 | */ | |
768 | if (skb->sk) | |
769 | skb_set_owner_w(frag, skb->sk); | |
770 | ||
771 | /* | |
772 | * Copy the packet header into the new buffer. | |
773 | */ | |
774 | skb_copy_from_linear_data(skb, skb_network_header(frag), hlen); | |
775 | ||
776 | /* | |
777 | * Build fragment header. | |
778 | */ | |
779 | fh->nexthdr = nexthdr; | |
780 | fh->reserved = 0; | |
781 | if (!frag_id) { | |
782 | ipv6_select_ident(net, fh, rt); | |
783 | frag_id = fh->identification; | |
784 | } else | |
785 | fh->identification = frag_id; | |
786 | ||
787 | /* | |
788 | * Copy a block of the IP datagram. | |
789 | */ | |
790 | BUG_ON(skb_copy_bits(skb, ptr, skb_transport_header(frag), | |
791 | len)); | |
792 | left -= len; | |
793 | ||
794 | fh->frag_off = htons(offset); | |
795 | if (left > 0) | |
796 | fh->frag_off |= htons(IP6_MF); | |
797 | ipv6_hdr(frag)->payload_len = htons(frag->len - | |
798 | sizeof(struct ipv6hdr)); | |
799 | ||
800 | ptr += len; | |
801 | offset += len; | |
802 | ||
803 | /* | |
804 | * Put this fragment into the sending queue. | |
805 | */ | |
806 | err = output(sk, frag); | |
807 | if (err) | |
808 | goto fail; | |
809 | ||
810 | IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)), | |
811 | IPSTATS_MIB_FRAGCREATES); | |
812 | } | |
813 | IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)), | |
814 | IPSTATS_MIB_FRAGOKS); | |
815 | consume_skb(skb); | |
816 | return err; | |
817 | ||
818 | fail: | |
819 | IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)), | |
820 | IPSTATS_MIB_FRAGFAILS); | |
821 | kfree_skb(skb); | |
822 | return err; | |
823 | } | |
824 | ||
825 | static inline int ip6_rt_check(const struct rt6key *rt_key, | |
826 | const struct in6_addr *fl_addr, | |
827 | const struct in6_addr *addr_cache) | |
828 | { | |
829 | return (rt_key->plen != 128 || !ipv6_addr_equal(fl_addr, &rt_key->addr)) && | |
830 | (!addr_cache || !ipv6_addr_equal(fl_addr, addr_cache)); | |
831 | } | |
832 | ||
833 | static struct dst_entry *ip6_sk_dst_check(struct sock *sk, | |
834 | struct dst_entry *dst, | |
835 | const struct flowi6 *fl6) | |
836 | { | |
837 | struct ipv6_pinfo *np = inet6_sk(sk); | |
838 | struct rt6_info *rt; | |
839 | ||
840 | if (!dst) | |
841 | goto out; | |
842 | ||
843 | if (dst->ops->family != AF_INET6) { | |
844 | dst_release(dst); | |
845 | return NULL; | |
846 | } | |
847 | ||
848 | rt = (struct rt6_info *)dst; | |
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, &fl6->daddr, np->daddr_cache) || | |
867 | #ifdef CONFIG_IPV6_SUBTREES | |
868 | ip6_rt_check(&rt->rt6i_src, &fl6->saddr, np->saddr_cache) || | |
869 | #endif | |
870 | (fl6->flowi6_oif && fl6->flowi6_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 flowi6 *fl6) | |
881 | { | |
882 | struct net *net = sock_net(sk); | |
883 | #ifdef CONFIG_IPV6_OPTIMISTIC_DAD | |
884 | struct neighbour *n; | |
885 | struct rt6_info *rt; | |
886 | #endif | |
887 | int err; | |
888 | ||
889 | /* The correct way to handle this would be to do | |
890 | * ip6_route_get_saddr, and then ip6_route_output; however, | |
891 | * the route-specific preferred source forces the | |
892 | * ip6_route_output call _before_ ip6_route_get_saddr. | |
893 | * | |
894 | * In source specific routing (no src=any default route), | |
895 | * ip6_route_output will fail given src=any saddr, though, so | |
896 | * that's why we try it again later. | |
897 | */ | |
898 | if (ipv6_addr_any(&fl6->saddr) && (!*dst || !(*dst)->error)) { | |
899 | struct rt6_info *rt; | |
900 | bool had_dst = *dst != NULL; | |
901 | ||
902 | if (!had_dst) | |
903 | *dst = ip6_route_output(net, sk, fl6); | |
904 | rt = (*dst)->error ? NULL : (struct rt6_info *)*dst; | |
905 | err = ip6_route_get_saddr(net, rt, &fl6->daddr, | |
906 | sk ? inet6_sk(sk)->srcprefs : 0, | |
907 | &fl6->saddr); | |
908 | if (err) | |
909 | goto out_err_release; | |
910 | ||
911 | /* If we had an erroneous initial result, pretend it | |
912 | * never existed and let the SA-enabled version take | |
913 | * over. | |
914 | */ | |
915 | if (!had_dst && (*dst)->error) { | |
916 | dst_release(*dst); | |
917 | *dst = NULL; | |
918 | } | |
919 | } | |
920 | ||
921 | if (!*dst) | |
922 | *dst = ip6_route_output(net, sk, fl6); | |
923 | ||
924 | err = (*dst)->error; | |
925 | if (err) | |
926 | goto out_err_release; | |
927 | ||
928 | #ifdef CONFIG_IPV6_OPTIMISTIC_DAD | |
929 | /* | |
930 | * Here if the dst entry we've looked up | |
931 | * has a neighbour entry that is in the INCOMPLETE | |
932 | * state and the src address from the flow is | |
933 | * marked as OPTIMISTIC, we release the found | |
934 | * dst entry and replace it instead with the | |
935 | * dst entry of the nexthop router | |
936 | */ | |
937 | rt = (struct rt6_info *) *dst; | |
938 | rcu_read_lock_bh(); | |
939 | n = __ipv6_neigh_lookup_noref(rt->dst.dev, rt6_nexthop(rt)); | |
940 | err = n && !(n->nud_state & NUD_VALID) ? -EINVAL : 0; | |
941 | rcu_read_unlock_bh(); | |
942 | ||
943 | if (err) { | |
944 | struct inet6_ifaddr *ifp; | |
945 | struct flowi6 fl_gw6; | |
946 | int redirect; | |
947 | ||
948 | ifp = ipv6_get_ifaddr(net, &fl6->saddr, | |
949 | (*dst)->dev, 1); | |
950 | ||
951 | redirect = (ifp && ifp->flags & IFA_F_OPTIMISTIC); | |
952 | if (ifp) | |
953 | in6_ifa_put(ifp); | |
954 | ||
955 | if (redirect) { | |
956 | /* | |
957 | * We need to get the dst entry for the | |
958 | * default router instead | |
959 | */ | |
960 | dst_release(*dst); | |
961 | memcpy(&fl_gw6, fl6, sizeof(struct flowi6)); | |
962 | memset(&fl_gw6.daddr, 0, sizeof(struct in6_addr)); | |
963 | *dst = ip6_route_output(net, sk, &fl_gw6); | |
964 | err = (*dst)->error; | |
965 | if (err) | |
966 | goto out_err_release; | |
967 | } | |
968 | } | |
969 | #endif | |
970 | ||
971 | return 0; | |
972 | ||
973 | out_err_release: | |
974 | if (err == -ENETUNREACH) | |
975 | IP6_INC_STATS(net, NULL, IPSTATS_MIB_OUTNOROUTES); | |
976 | dst_release(*dst); | |
977 | *dst = NULL; | |
978 | return err; | |
979 | } | |
980 | ||
981 | /** | |
982 | * ip6_dst_lookup - perform route lookup on flow | |
983 | * @sk: socket which provides route info | |
984 | * @dst: pointer to dst_entry * for result | |
985 | * @fl6: flow to lookup | |
986 | * | |
987 | * This function performs a route lookup on the given flow. | |
988 | * | |
989 | * It returns zero on success, or a standard errno code on error. | |
990 | */ | |
991 | int ip6_dst_lookup(struct sock *sk, struct dst_entry **dst, struct flowi6 *fl6) | |
992 | { | |
993 | *dst = NULL; | |
994 | return ip6_dst_lookup_tail(sk, dst, fl6); | |
995 | } | |
996 | EXPORT_SYMBOL_GPL(ip6_dst_lookup); | |
997 | ||
998 | /** | |
999 | * ip6_dst_lookup_flow - perform route lookup on flow with ipsec | |
1000 | * @sk: socket which provides route info | |
1001 | * @fl6: flow to lookup | |
1002 | * @final_dst: final destination address for ipsec lookup | |
1003 | * | |
1004 | * This function performs a route lookup on the given flow. | |
1005 | * | |
1006 | * It returns a valid dst pointer on success, or a pointer encoded | |
1007 | * error code. | |
1008 | */ | |
1009 | struct dst_entry *ip6_dst_lookup_flow(struct sock *sk, struct flowi6 *fl6, | |
1010 | const struct in6_addr *final_dst) | |
1011 | { | |
1012 | struct dst_entry *dst = NULL; | |
1013 | int err; | |
1014 | ||
1015 | err = ip6_dst_lookup_tail(sk, &dst, fl6); | |
1016 | if (err) | |
1017 | return ERR_PTR(err); | |
1018 | if (final_dst) | |
1019 | fl6->daddr = *final_dst; | |
1020 | ||
1021 | return xfrm_lookup_route(sock_net(sk), dst, flowi6_to_flowi(fl6), sk, 0); | |
1022 | } | |
1023 | EXPORT_SYMBOL_GPL(ip6_dst_lookup_flow); | |
1024 | ||
1025 | /** | |
1026 | * ip6_sk_dst_lookup_flow - perform socket cached route lookup on flow | |
1027 | * @sk: socket which provides the dst cache and route info | |
1028 | * @fl6: flow to lookup | |
1029 | * @final_dst: final destination address for ipsec lookup | |
1030 | * | |
1031 | * This function performs a route lookup on the given flow with the | |
1032 | * possibility of using the cached route in the socket if it is valid. | |
1033 | * It will take the socket dst lock when operating on the dst cache. | |
1034 | * As a result, this function can only be used in process context. | |
1035 | * | |
1036 | * It returns a valid dst pointer on success, or a pointer encoded | |
1037 | * error code. | |
1038 | */ | |
1039 | struct dst_entry *ip6_sk_dst_lookup_flow(struct sock *sk, struct flowi6 *fl6, | |
1040 | const struct in6_addr *final_dst) | |
1041 | { | |
1042 | struct dst_entry *dst = sk_dst_check(sk, inet6_sk(sk)->dst_cookie); | |
1043 | int err; | |
1044 | ||
1045 | dst = ip6_sk_dst_check(sk, dst, fl6); | |
1046 | ||
1047 | err = ip6_dst_lookup_tail(sk, &dst, fl6); | |
1048 | if (err) | |
1049 | return ERR_PTR(err); | |
1050 | if (final_dst) | |
1051 | fl6->daddr = *final_dst; | |
1052 | ||
1053 | return xfrm_lookup_route(sock_net(sk), dst, flowi6_to_flowi(fl6), sk, 0); | |
1054 | } | |
1055 | EXPORT_SYMBOL_GPL(ip6_sk_dst_lookup_flow); | |
1056 | ||
1057 | static inline int ip6_ufo_append_data(struct sock *sk, | |
1058 | struct sk_buff_head *queue, | |
1059 | int getfrag(void *from, char *to, int offset, int len, | |
1060 | int odd, struct sk_buff *skb), | |
1061 | void *from, int length, int hh_len, int fragheaderlen, | |
1062 | int transhdrlen, int mtu, unsigned int flags, | |
1063 | struct rt6_info *rt) | |
1064 | ||
1065 | { | |
1066 | struct sk_buff *skb; | |
1067 | struct frag_hdr fhdr; | |
1068 | int err; | |
1069 | ||
1070 | /* There is support for UDP large send offload by network | |
1071 | * device, so create one single skb packet containing complete | |
1072 | * udp datagram | |
1073 | */ | |
1074 | skb = skb_peek_tail(queue); | |
1075 | if (!skb) { | |
1076 | skb = sock_alloc_send_skb(sk, | |
1077 | hh_len + fragheaderlen + transhdrlen + 20, | |
1078 | (flags & MSG_DONTWAIT), &err); | |
1079 | if (!skb) | |
1080 | return err; | |
1081 | ||
1082 | /* reserve space for Hardware header */ | |
1083 | skb_reserve(skb, hh_len); | |
1084 | ||
1085 | /* create space for UDP/IP header */ | |
1086 | skb_put(skb, fragheaderlen + transhdrlen); | |
1087 | ||
1088 | /* initialize network header pointer */ | |
1089 | skb_reset_network_header(skb); | |
1090 | ||
1091 | /* initialize protocol header pointer */ | |
1092 | skb->transport_header = skb->network_header + fragheaderlen; | |
1093 | ||
1094 | skb->protocol = htons(ETH_P_IPV6); | |
1095 | skb->csum = 0; | |
1096 | ||
1097 | __skb_queue_tail(queue, skb); | |
1098 | } else if (skb_is_gso(skb)) { | |
1099 | goto append; | |
1100 | } | |
1101 | ||
1102 | skb->ip_summed = CHECKSUM_PARTIAL; | |
1103 | /* Specify the length of each IPv6 datagram fragment. | |
1104 | * It has to be a multiple of 8. | |
1105 | */ | |
1106 | skb_shinfo(skb)->gso_size = (mtu - fragheaderlen - | |
1107 | sizeof(struct frag_hdr)) & ~7; | |
1108 | skb_shinfo(skb)->gso_type = SKB_GSO_UDP; | |
1109 | ipv6_select_ident(sock_net(sk), &fhdr, rt); | |
1110 | skb_shinfo(skb)->ip6_frag_id = fhdr.identification; | |
1111 | ||
1112 | append: | |
1113 | return skb_append_datato_frags(sk, skb, getfrag, from, | |
1114 | (length - transhdrlen)); | |
1115 | } | |
1116 | ||
1117 | static inline struct ipv6_opt_hdr *ip6_opt_dup(struct ipv6_opt_hdr *src, | |
1118 | gfp_t gfp) | |
1119 | { | |
1120 | return src ? kmemdup(src, (src->hdrlen + 1) * 8, gfp) : NULL; | |
1121 | } | |
1122 | ||
1123 | static inline struct ipv6_rt_hdr *ip6_rthdr_dup(struct ipv6_rt_hdr *src, | |
1124 | gfp_t gfp) | |
1125 | { | |
1126 | return src ? kmemdup(src, (src->hdrlen + 1) * 8, gfp) : NULL; | |
1127 | } | |
1128 | ||
1129 | static void ip6_append_data_mtu(unsigned int *mtu, | |
1130 | int *maxfraglen, | |
1131 | unsigned int fragheaderlen, | |
1132 | struct sk_buff *skb, | |
1133 | struct rt6_info *rt, | |
1134 | unsigned int orig_mtu) | |
1135 | { | |
1136 | if (!(rt->dst.flags & DST_XFRM_TUNNEL)) { | |
1137 | if (!skb) { | |
1138 | /* first fragment, reserve header_len */ | |
1139 | *mtu = orig_mtu - rt->dst.header_len; | |
1140 | ||
1141 | } else { | |
1142 | /* | |
1143 | * this fragment is not first, the headers | |
1144 | * space is regarded as data space. | |
1145 | */ | |
1146 | *mtu = orig_mtu; | |
1147 | } | |
1148 | *maxfraglen = ((*mtu - fragheaderlen) & ~7) | |
1149 | + fragheaderlen - sizeof(struct frag_hdr); | |
1150 | } | |
1151 | } | |
1152 | ||
1153 | static int ip6_setup_cork(struct sock *sk, struct inet_cork_full *cork, | |
1154 | struct inet6_cork *v6_cork, | |
1155 | int hlimit, int tclass, struct ipv6_txoptions *opt, | |
1156 | struct rt6_info *rt, struct flowi6 *fl6) | |
1157 | { | |
1158 | struct ipv6_pinfo *np = inet6_sk(sk); | |
1159 | unsigned int mtu; | |
1160 | ||
1161 | /* | |
1162 | * setup for corking | |
1163 | */ | |
1164 | if (opt) { | |
1165 | if (WARN_ON(v6_cork->opt)) | |
1166 | return -EINVAL; | |
1167 | ||
1168 | v6_cork->opt = kzalloc(opt->tot_len, sk->sk_allocation); | |
1169 | if (unlikely(!v6_cork->opt)) | |
1170 | return -ENOBUFS; | |
1171 | ||
1172 | v6_cork->opt->tot_len = opt->tot_len; | |
1173 | v6_cork->opt->opt_flen = opt->opt_flen; | |
1174 | v6_cork->opt->opt_nflen = opt->opt_nflen; | |
1175 | ||
1176 | v6_cork->opt->dst0opt = ip6_opt_dup(opt->dst0opt, | |
1177 | sk->sk_allocation); | |
1178 | if (opt->dst0opt && !v6_cork->opt->dst0opt) | |
1179 | return -ENOBUFS; | |
1180 | ||
1181 | v6_cork->opt->dst1opt = ip6_opt_dup(opt->dst1opt, | |
1182 | sk->sk_allocation); | |
1183 | if (opt->dst1opt && !v6_cork->opt->dst1opt) | |
1184 | return -ENOBUFS; | |
1185 | ||
1186 | v6_cork->opt->hopopt = ip6_opt_dup(opt->hopopt, | |
1187 | sk->sk_allocation); | |
1188 | if (opt->hopopt && !v6_cork->opt->hopopt) | |
1189 | return -ENOBUFS; | |
1190 | ||
1191 | v6_cork->opt->srcrt = ip6_rthdr_dup(opt->srcrt, | |
1192 | sk->sk_allocation); | |
1193 | if (opt->srcrt && !v6_cork->opt->srcrt) | |
1194 | return -ENOBUFS; | |
1195 | ||
1196 | /* need source address above miyazawa*/ | |
1197 | } | |
1198 | dst_hold(&rt->dst); | |
1199 | cork->base.dst = &rt->dst; | |
1200 | cork->fl.u.ip6 = *fl6; | |
1201 | v6_cork->hop_limit = hlimit; | |
1202 | v6_cork->tclass = tclass; | |
1203 | if (rt->dst.flags & DST_XFRM_TUNNEL) | |
1204 | mtu = np->pmtudisc >= IPV6_PMTUDISC_PROBE ? | |
1205 | rt->dst.dev->mtu : dst_mtu(&rt->dst); | |
1206 | else | |
1207 | mtu = np->pmtudisc >= IPV6_PMTUDISC_PROBE ? | |
1208 | rt->dst.dev->mtu : dst_mtu(rt->dst.path); | |
1209 | if (np->frag_size < mtu) { | |
1210 | if (np->frag_size) | |
1211 | mtu = np->frag_size; | |
1212 | } | |
1213 | cork->base.fragsize = mtu; | |
1214 | if (dst_allfrag(rt->dst.path)) | |
1215 | cork->base.flags |= IPCORK_ALLFRAG; | |
1216 | cork->base.length = 0; | |
1217 | ||
1218 | return 0; | |
1219 | } | |
1220 | ||
1221 | static int __ip6_append_data(struct sock *sk, | |
1222 | struct flowi6 *fl6, | |
1223 | struct sk_buff_head *queue, | |
1224 | struct inet_cork *cork, | |
1225 | struct inet6_cork *v6_cork, | |
1226 | struct page_frag *pfrag, | |
1227 | int getfrag(void *from, char *to, int offset, | |
1228 | int len, int odd, struct sk_buff *skb), | |
1229 | void *from, int length, int transhdrlen, | |
1230 | unsigned int flags, int dontfrag) | |
1231 | { | |
1232 | struct sk_buff *skb, *skb_prev = NULL; | |
1233 | unsigned int maxfraglen, fragheaderlen, mtu, orig_mtu; | |
1234 | int exthdrlen = 0; | |
1235 | int dst_exthdrlen = 0; | |
1236 | int hh_len; | |
1237 | int copy; | |
1238 | int err; | |
1239 | int offset = 0; | |
1240 | __u8 tx_flags = 0; | |
1241 | u32 tskey = 0; | |
1242 | struct rt6_info *rt = (struct rt6_info *)cork->dst; | |
1243 | struct ipv6_txoptions *opt = v6_cork->opt; | |
1244 | int csummode = CHECKSUM_NONE; | |
1245 | ||
1246 | skb = skb_peek_tail(queue); | |
1247 | if (!skb) { | |
1248 | exthdrlen = opt ? opt->opt_flen : 0; | |
1249 | dst_exthdrlen = rt->dst.header_len - rt->rt6i_nfheader_len; | |
1250 | } | |
1251 | ||
1252 | mtu = cork->fragsize; | |
1253 | orig_mtu = mtu; | |
1254 | ||
1255 | hh_len = LL_RESERVED_SPACE(rt->dst.dev); | |
1256 | ||
1257 | fragheaderlen = sizeof(struct ipv6hdr) + rt->rt6i_nfheader_len + | |
1258 | (opt ? opt->opt_nflen : 0); | |
1259 | maxfraglen = ((mtu - fragheaderlen) & ~7) + fragheaderlen - | |
1260 | sizeof(struct frag_hdr); | |
1261 | ||
1262 | if (mtu <= sizeof(struct ipv6hdr) + IPV6_MAXPLEN) { | |
1263 | unsigned int maxnonfragsize, headersize; | |
1264 | ||
1265 | headersize = sizeof(struct ipv6hdr) + | |
1266 | (opt ? opt->opt_flen + opt->opt_nflen : 0) + | |
1267 | (dst_allfrag(&rt->dst) ? | |
1268 | sizeof(struct frag_hdr) : 0) + | |
1269 | rt->rt6i_nfheader_len; | |
1270 | ||
1271 | if (ip6_sk_ignore_df(sk)) | |
1272 | maxnonfragsize = sizeof(struct ipv6hdr) + IPV6_MAXPLEN; | |
1273 | else | |
1274 | maxnonfragsize = mtu; | |
1275 | ||
1276 | /* dontfrag active */ | |
1277 | if ((cork->length + length > mtu - headersize) && dontfrag && | |
1278 | (sk->sk_protocol == IPPROTO_UDP || | |
1279 | sk->sk_protocol == IPPROTO_RAW)) { | |
1280 | ipv6_local_rxpmtu(sk, fl6, mtu - headersize + | |
1281 | sizeof(struct ipv6hdr)); | |
1282 | goto emsgsize; | |
1283 | } | |
1284 | ||
1285 | if (cork->length + length > maxnonfragsize - headersize) { | |
1286 | emsgsize: | |
1287 | ipv6_local_error(sk, EMSGSIZE, fl6, | |
1288 | mtu - headersize + | |
1289 | sizeof(struct ipv6hdr)); | |
1290 | return -EMSGSIZE; | |
1291 | } | |
1292 | } | |
1293 | ||
1294 | if (sk->sk_type == SOCK_DGRAM || sk->sk_type == SOCK_RAW) { | |
1295 | sock_tx_timestamp(sk, &tx_flags); | |
1296 | if (tx_flags & SKBTX_ANY_SW_TSTAMP && | |
1297 | sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID) | |
1298 | tskey = sk->sk_tskey++; | |
1299 | } | |
1300 | ||
1301 | /* If this is the first and only packet and device | |
1302 | * supports checksum offloading, let's use it. | |
1303 | * Use transhdrlen, same as IPv4, because partial | |
1304 | * sums only work when transhdrlen is set. | |
1305 | */ | |
1306 | if (transhdrlen && sk->sk_protocol == IPPROTO_UDP && | |
1307 | length + fragheaderlen < mtu && | |
1308 | rt->dst.dev->features & NETIF_F_V6_CSUM && | |
1309 | !exthdrlen) | |
1310 | csummode = CHECKSUM_PARTIAL; | |
1311 | /* | |
1312 | * Let's try using as much space as possible. | |
1313 | * Use MTU if total length of the message fits into the MTU. | |
1314 | * Otherwise, we need to reserve fragment header and | |
1315 | * fragment alignment (= 8-15 octects, in total). | |
1316 | * | |
1317 | * Note that we may need to "move" the data from the tail of | |
1318 | * of the buffer to the new fragment when we split | |
1319 | * the message. | |
1320 | * | |
1321 | * FIXME: It may be fragmented into multiple chunks | |
1322 | * at once if non-fragmentable extension headers | |
1323 | * are too large. | |
1324 | * --yoshfuji | |
1325 | */ | |
1326 | ||
1327 | cork->length += length; | |
1328 | if (((length > mtu) || | |
1329 | (skb && skb_is_gso(skb))) && | |
1330 | (sk->sk_protocol == IPPROTO_UDP) && | |
1331 | (rt->dst.dev->features & NETIF_F_UFO) && | |
1332 | (sk->sk_type == SOCK_DGRAM)) { | |
1333 | err = ip6_ufo_append_data(sk, queue, getfrag, from, length, | |
1334 | hh_len, fragheaderlen, | |
1335 | transhdrlen, mtu, flags, rt); | |
1336 | if (err) | |
1337 | goto error; | |
1338 | return 0; | |
1339 | } | |
1340 | ||
1341 | if (!skb) | |
1342 | goto alloc_new_skb; | |
1343 | ||
1344 | while (length > 0) { | |
1345 | /* Check if the remaining data fits into current packet. */ | |
1346 | copy = (cork->length <= mtu && !(cork->flags & IPCORK_ALLFRAG) ? mtu : maxfraglen) - skb->len; | |
1347 | if (copy < length) | |
1348 | copy = maxfraglen - skb->len; | |
1349 | ||
1350 | if (copy <= 0) { | |
1351 | char *data; | |
1352 | unsigned int datalen; | |
1353 | unsigned int fraglen; | |
1354 | unsigned int fraggap; | |
1355 | unsigned int alloclen; | |
1356 | alloc_new_skb: | |
1357 | /* There's no room in the current skb */ | |
1358 | if (skb) | |
1359 | fraggap = skb->len - maxfraglen; | |
1360 | else | |
1361 | fraggap = 0; | |
1362 | /* update mtu and maxfraglen if necessary */ | |
1363 | if (!skb || !skb_prev) | |
1364 | ip6_append_data_mtu(&mtu, &maxfraglen, | |
1365 | fragheaderlen, skb, rt, | |
1366 | orig_mtu); | |
1367 | ||
1368 | skb_prev = skb; | |
1369 | ||
1370 | /* | |
1371 | * If remaining data exceeds the mtu, | |
1372 | * we know we need more fragment(s). | |
1373 | */ | |
1374 | datalen = length + fraggap; | |
1375 | ||
1376 | if (datalen > (cork->length <= mtu && !(cork->flags & IPCORK_ALLFRAG) ? mtu : maxfraglen) - fragheaderlen) | |
1377 | datalen = maxfraglen - fragheaderlen - rt->dst.trailer_len; | |
1378 | if ((flags & MSG_MORE) && | |
1379 | !(rt->dst.dev->features&NETIF_F_SG)) | |
1380 | alloclen = mtu; | |
1381 | else | |
1382 | alloclen = datalen + fragheaderlen; | |
1383 | ||
1384 | alloclen += dst_exthdrlen; | |
1385 | ||
1386 | if (datalen != length + fraggap) { | |
1387 | /* | |
1388 | * this is not the last fragment, the trailer | |
1389 | * space is regarded as data space. | |
1390 | */ | |
1391 | datalen += rt->dst.trailer_len; | |
1392 | } | |
1393 | ||
1394 | alloclen += rt->dst.trailer_len; | |
1395 | fraglen = datalen + fragheaderlen; | |
1396 | ||
1397 | /* | |
1398 | * We just reserve space for fragment header. | |
1399 | * Note: this may be overallocation if the message | |
1400 | * (without MSG_MORE) fits into the MTU. | |
1401 | */ | |
1402 | alloclen += sizeof(struct frag_hdr); | |
1403 | ||
1404 | if (transhdrlen) { | |
1405 | skb = sock_alloc_send_skb(sk, | |
1406 | alloclen + hh_len, | |
1407 | (flags & MSG_DONTWAIT), &err); | |
1408 | } else { | |
1409 | skb = NULL; | |
1410 | if (atomic_read(&sk->sk_wmem_alloc) <= | |
1411 | 2 * sk->sk_sndbuf) | |
1412 | skb = sock_wmalloc(sk, | |
1413 | alloclen + hh_len, 1, | |
1414 | sk->sk_allocation); | |
1415 | if (unlikely(!skb)) | |
1416 | err = -ENOBUFS; | |
1417 | } | |
1418 | if (!skb) | |
1419 | goto error; | |
1420 | /* | |
1421 | * Fill in the control structures | |
1422 | */ | |
1423 | skb->protocol = htons(ETH_P_IPV6); | |
1424 | skb->ip_summed = csummode; | |
1425 | skb->csum = 0; | |
1426 | /* reserve for fragmentation and ipsec header */ | |
1427 | skb_reserve(skb, hh_len + sizeof(struct frag_hdr) + | |
1428 | dst_exthdrlen); | |
1429 | ||
1430 | /* Only the initial fragment is time stamped */ | |
1431 | skb_shinfo(skb)->tx_flags = tx_flags; | |
1432 | tx_flags = 0; | |
1433 | skb_shinfo(skb)->tskey = tskey; | |
1434 | tskey = 0; | |
1435 | ||
1436 | /* | |
1437 | * Find where to start putting bytes | |
1438 | */ | |
1439 | data = skb_put(skb, fraglen); | |
1440 | skb_set_network_header(skb, exthdrlen); | |
1441 | data += fragheaderlen; | |
1442 | skb->transport_header = (skb->network_header + | |
1443 | fragheaderlen); | |
1444 | if (fraggap) { | |
1445 | skb->csum = skb_copy_and_csum_bits( | |
1446 | skb_prev, maxfraglen, | |
1447 | data + transhdrlen, fraggap, 0); | |
1448 | skb_prev->csum = csum_sub(skb_prev->csum, | |
1449 | skb->csum); | |
1450 | data += fraggap; | |
1451 | pskb_trim_unique(skb_prev, maxfraglen); | |
1452 | } | |
1453 | copy = datalen - transhdrlen - fraggap; | |
1454 | ||
1455 | if (copy < 0) { | |
1456 | err = -EINVAL; | |
1457 | kfree_skb(skb); | |
1458 | goto error; | |
1459 | } else if (copy > 0 && getfrag(from, data + transhdrlen, offset, copy, fraggap, skb) < 0) { | |
1460 | err = -EFAULT; | |
1461 | kfree_skb(skb); | |
1462 | goto error; | |
1463 | } | |
1464 | ||
1465 | offset += copy; | |
1466 | length -= datalen - fraggap; | |
1467 | transhdrlen = 0; | |
1468 | exthdrlen = 0; | |
1469 | dst_exthdrlen = 0; | |
1470 | ||
1471 | /* | |
1472 | * Put the packet on the pending queue | |
1473 | */ | |
1474 | __skb_queue_tail(queue, skb); | |
1475 | continue; | |
1476 | } | |
1477 | ||
1478 | if (copy > length) | |
1479 | copy = length; | |
1480 | ||
1481 | if (!(rt->dst.dev->features&NETIF_F_SG)) { | |
1482 | unsigned int off; | |
1483 | ||
1484 | off = skb->len; | |
1485 | if (getfrag(from, skb_put(skb, copy), | |
1486 | offset, copy, off, skb) < 0) { | |
1487 | __skb_trim(skb, off); | |
1488 | err = -EFAULT; | |
1489 | goto error; | |
1490 | } | |
1491 | } else { | |
1492 | int i = skb_shinfo(skb)->nr_frags; | |
1493 | ||
1494 | err = -ENOMEM; | |
1495 | if (!sk_page_frag_refill(sk, pfrag)) | |
1496 | goto error; | |
1497 | ||
1498 | if (!skb_can_coalesce(skb, i, pfrag->page, | |
1499 | pfrag->offset)) { | |
1500 | err = -EMSGSIZE; | |
1501 | if (i == MAX_SKB_FRAGS) | |
1502 | goto error; | |
1503 | ||
1504 | __skb_fill_page_desc(skb, i, pfrag->page, | |
1505 | pfrag->offset, 0); | |
1506 | skb_shinfo(skb)->nr_frags = ++i; | |
1507 | get_page(pfrag->page); | |
1508 | } | |
1509 | copy = min_t(int, copy, pfrag->size - pfrag->offset); | |
1510 | if (getfrag(from, | |
1511 | page_address(pfrag->page) + pfrag->offset, | |
1512 | offset, copy, skb->len, skb) < 0) | |
1513 | goto error_efault; | |
1514 | ||
1515 | pfrag->offset += copy; | |
1516 | skb_frag_size_add(&skb_shinfo(skb)->frags[i - 1], copy); | |
1517 | skb->len += copy; | |
1518 | skb->data_len += copy; | |
1519 | skb->truesize += copy; | |
1520 | atomic_add(copy, &sk->sk_wmem_alloc); | |
1521 | } | |
1522 | offset += copy; | |
1523 | length -= copy; | |
1524 | } | |
1525 | ||
1526 | return 0; | |
1527 | ||
1528 | error_efault: | |
1529 | err = -EFAULT; | |
1530 | error: | |
1531 | cork->length -= length; | |
1532 | IP6_INC_STATS(sock_net(sk), rt->rt6i_idev, IPSTATS_MIB_OUTDISCARDS); | |
1533 | return err; | |
1534 | } | |
1535 | ||
1536 | int ip6_append_data(struct sock *sk, | |
1537 | int getfrag(void *from, char *to, int offset, int len, | |
1538 | int odd, struct sk_buff *skb), | |
1539 | void *from, int length, int transhdrlen, int hlimit, | |
1540 | int tclass, struct ipv6_txoptions *opt, struct flowi6 *fl6, | |
1541 | struct rt6_info *rt, unsigned int flags, int dontfrag) | |
1542 | { | |
1543 | struct inet_sock *inet = inet_sk(sk); | |
1544 | struct ipv6_pinfo *np = inet6_sk(sk); | |
1545 | int exthdrlen; | |
1546 | int err; | |
1547 | ||
1548 | if (flags&MSG_PROBE) | |
1549 | return 0; | |
1550 | if (skb_queue_empty(&sk->sk_write_queue)) { | |
1551 | /* | |
1552 | * setup for corking | |
1553 | */ | |
1554 | err = ip6_setup_cork(sk, &inet->cork, &np->cork, hlimit, | |
1555 | tclass, opt, rt, fl6); | |
1556 | if (err) | |
1557 | return err; | |
1558 | ||
1559 | exthdrlen = (opt ? opt->opt_flen : 0); | |
1560 | length += exthdrlen; | |
1561 | transhdrlen += exthdrlen; | |
1562 | } else { | |
1563 | fl6 = &inet->cork.fl.u.ip6; | |
1564 | transhdrlen = 0; | |
1565 | } | |
1566 | ||
1567 | return __ip6_append_data(sk, fl6, &sk->sk_write_queue, &inet->cork.base, | |
1568 | &np->cork, sk_page_frag(sk), getfrag, | |
1569 | from, length, transhdrlen, flags, dontfrag); | |
1570 | } | |
1571 | EXPORT_SYMBOL_GPL(ip6_append_data); | |
1572 | ||
1573 | static void ip6_cork_release(struct inet_cork_full *cork, | |
1574 | struct inet6_cork *v6_cork) | |
1575 | { | |
1576 | if (v6_cork->opt) { | |
1577 | kfree(v6_cork->opt->dst0opt); | |
1578 | kfree(v6_cork->opt->dst1opt); | |
1579 | kfree(v6_cork->opt->hopopt); | |
1580 | kfree(v6_cork->opt->srcrt); | |
1581 | kfree(v6_cork->opt); | |
1582 | v6_cork->opt = NULL; | |
1583 | } | |
1584 | ||
1585 | if (cork->base.dst) { | |
1586 | dst_release(cork->base.dst); | |
1587 | cork->base.dst = NULL; | |
1588 | cork->base.flags &= ~IPCORK_ALLFRAG; | |
1589 | } | |
1590 | memset(&cork->fl, 0, sizeof(cork->fl)); | |
1591 | } | |
1592 | ||
1593 | struct sk_buff *__ip6_make_skb(struct sock *sk, | |
1594 | struct sk_buff_head *queue, | |
1595 | struct inet_cork_full *cork, | |
1596 | struct inet6_cork *v6_cork) | |
1597 | { | |
1598 | struct sk_buff *skb, *tmp_skb; | |
1599 | struct sk_buff **tail_skb; | |
1600 | struct in6_addr final_dst_buf, *final_dst = &final_dst_buf; | |
1601 | struct ipv6_pinfo *np = inet6_sk(sk); | |
1602 | struct net *net = sock_net(sk); | |
1603 | struct ipv6hdr *hdr; | |
1604 | struct ipv6_txoptions *opt = v6_cork->opt; | |
1605 | struct rt6_info *rt = (struct rt6_info *)cork->base.dst; | |
1606 | struct flowi6 *fl6 = &cork->fl.u.ip6; | |
1607 | unsigned char proto = fl6->flowi6_proto; | |
1608 | ||
1609 | skb = __skb_dequeue(queue); | |
1610 | if (!skb) | |
1611 | goto out; | |
1612 | tail_skb = &(skb_shinfo(skb)->frag_list); | |
1613 | ||
1614 | /* move skb->data to ip header from ext header */ | |
1615 | if (skb->data < skb_network_header(skb)) | |
1616 | __skb_pull(skb, skb_network_offset(skb)); | |
1617 | while ((tmp_skb = __skb_dequeue(queue)) != NULL) { | |
1618 | __skb_pull(tmp_skb, skb_network_header_len(skb)); | |
1619 | *tail_skb = tmp_skb; | |
1620 | tail_skb = &(tmp_skb->next); | |
1621 | skb->len += tmp_skb->len; | |
1622 | skb->data_len += tmp_skb->len; | |
1623 | skb->truesize += tmp_skb->truesize; | |
1624 | tmp_skb->destructor = NULL; | |
1625 | tmp_skb->sk = NULL; | |
1626 | } | |
1627 | ||
1628 | /* Allow local fragmentation. */ | |
1629 | skb->ignore_df = ip6_sk_ignore_df(sk); | |
1630 | ||
1631 | *final_dst = fl6->daddr; | |
1632 | __skb_pull(skb, skb_network_header_len(skb)); | |
1633 | if (opt && opt->opt_flen) | |
1634 | ipv6_push_frag_opts(skb, opt, &proto); | |
1635 | if (opt && opt->opt_nflen) | |
1636 | ipv6_push_nfrag_opts(skb, opt, &proto, &final_dst); | |
1637 | ||
1638 | skb_push(skb, sizeof(struct ipv6hdr)); | |
1639 | skb_reset_network_header(skb); | |
1640 | hdr = ipv6_hdr(skb); | |
1641 | ||
1642 | ip6_flow_hdr(hdr, v6_cork->tclass, | |
1643 | ip6_make_flowlabel(net, skb, fl6->flowlabel, | |
1644 | np->autoflowlabel)); | |
1645 | hdr->hop_limit = v6_cork->hop_limit; | |
1646 | hdr->nexthdr = proto; | |
1647 | hdr->saddr = fl6->saddr; | |
1648 | hdr->daddr = *final_dst; | |
1649 | ||
1650 | skb->priority = sk->sk_priority; | |
1651 | skb->mark = sk->sk_mark; | |
1652 | ||
1653 | skb_dst_set(skb, dst_clone(&rt->dst)); | |
1654 | IP6_UPD_PO_STATS(net, rt->rt6i_idev, IPSTATS_MIB_OUT, skb->len); | |
1655 | if (proto == IPPROTO_ICMPV6) { | |
1656 | struct inet6_dev *idev = ip6_dst_idev(skb_dst(skb)); | |
1657 | ||
1658 | ICMP6MSGOUT_INC_STATS(net, idev, icmp6_hdr(skb)->icmp6_type); | |
1659 | ICMP6_INC_STATS(net, idev, ICMP6_MIB_OUTMSGS); | |
1660 | } | |
1661 | ||
1662 | ip6_cork_release(cork, v6_cork); | |
1663 | out: | |
1664 | return skb; | |
1665 | } | |
1666 | ||
1667 | int ip6_send_skb(struct sk_buff *skb) | |
1668 | { | |
1669 | struct net *net = sock_net(skb->sk); | |
1670 | struct rt6_info *rt = (struct rt6_info *)skb_dst(skb); | |
1671 | int err; | |
1672 | ||
1673 | err = ip6_local_out(skb); | |
1674 | if (err) { | |
1675 | if (err > 0) | |
1676 | err = net_xmit_errno(err); | |
1677 | if (err) | |
1678 | IP6_INC_STATS(net, rt->rt6i_idev, | |
1679 | IPSTATS_MIB_OUTDISCARDS); | |
1680 | } | |
1681 | ||
1682 | return err; | |
1683 | } | |
1684 | ||
1685 | int ip6_push_pending_frames(struct sock *sk) | |
1686 | { | |
1687 | struct sk_buff *skb; | |
1688 | ||
1689 | skb = ip6_finish_skb(sk); | |
1690 | if (!skb) | |
1691 | return 0; | |
1692 | ||
1693 | return ip6_send_skb(skb); | |
1694 | } | |
1695 | EXPORT_SYMBOL_GPL(ip6_push_pending_frames); | |
1696 | ||
1697 | static void __ip6_flush_pending_frames(struct sock *sk, | |
1698 | struct sk_buff_head *queue, | |
1699 | struct inet_cork_full *cork, | |
1700 | struct inet6_cork *v6_cork) | |
1701 | { | |
1702 | struct sk_buff *skb; | |
1703 | ||
1704 | while ((skb = __skb_dequeue_tail(queue)) != NULL) { | |
1705 | if (skb_dst(skb)) | |
1706 | IP6_INC_STATS(sock_net(sk), ip6_dst_idev(skb_dst(skb)), | |
1707 | IPSTATS_MIB_OUTDISCARDS); | |
1708 | kfree_skb(skb); | |
1709 | } | |
1710 | ||
1711 | ip6_cork_release(cork, v6_cork); | |
1712 | } | |
1713 | ||
1714 | void ip6_flush_pending_frames(struct sock *sk) | |
1715 | { | |
1716 | __ip6_flush_pending_frames(sk, &sk->sk_write_queue, | |
1717 | &inet_sk(sk)->cork, &inet6_sk(sk)->cork); | |
1718 | } | |
1719 | EXPORT_SYMBOL_GPL(ip6_flush_pending_frames); | |
1720 | ||
1721 | struct sk_buff *ip6_make_skb(struct sock *sk, | |
1722 | int getfrag(void *from, char *to, int offset, | |
1723 | int len, int odd, struct sk_buff *skb), | |
1724 | void *from, int length, int transhdrlen, | |
1725 | int hlimit, int tclass, | |
1726 | struct ipv6_txoptions *opt, struct flowi6 *fl6, | |
1727 | struct rt6_info *rt, unsigned int flags, | |
1728 | int dontfrag) | |
1729 | { | |
1730 | struct inet_cork_full cork; | |
1731 | struct inet6_cork v6_cork; | |
1732 | struct sk_buff_head queue; | |
1733 | int exthdrlen = (opt ? opt->opt_flen : 0); | |
1734 | int err; | |
1735 | ||
1736 | if (flags & MSG_PROBE) | |
1737 | return NULL; | |
1738 | ||
1739 | __skb_queue_head_init(&queue); | |
1740 | ||
1741 | cork.base.flags = 0; | |
1742 | cork.base.addr = 0; | |
1743 | cork.base.opt = NULL; | |
1744 | v6_cork.opt = NULL; | |
1745 | err = ip6_setup_cork(sk, &cork, &v6_cork, hlimit, tclass, opt, rt, fl6); | |
1746 | if (err) | |
1747 | return ERR_PTR(err); | |
1748 | ||
1749 | if (dontfrag < 0) | |
1750 | dontfrag = inet6_sk(sk)->dontfrag; | |
1751 | ||
1752 | err = __ip6_append_data(sk, fl6, &queue, &cork.base, &v6_cork, | |
1753 | ¤t->task_frag, getfrag, from, | |
1754 | length + exthdrlen, transhdrlen + exthdrlen, | |
1755 | flags, dontfrag); | |
1756 | if (err) { | |
1757 | __ip6_flush_pending_frames(sk, &queue, &cork, &v6_cork); | |
1758 | return ERR_PTR(err); | |
1759 | } | |
1760 | ||
1761 | return __ip6_make_skb(sk, &queue, &cork, &v6_cork); | |
1762 | } |