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Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * IPv6 output functions | |
1ab1457c | 3 | * Linux INET6 implementation |
1da177e4 LT |
4 | * |
5 | * Authors: | |
1ab1457c | 6 | * Pedro Roque <roque@di.fc.ul.pt> |
1da177e4 LT |
7 | * |
8 | * $Id: ip6_output.c,v 1.34 2002/02/01 22:01:04 davem Exp $ | |
9 | * | |
10 | * Based on linux/net/ipv4/ip_output.c | |
11 | * | |
12 | * This program is free software; you can redistribute it and/or | |
13 | * modify it under the terms of the GNU General Public License | |
14 | * as published by the Free Software Foundation; either version | |
15 | * 2 of the License, or (at your option) any later version. | |
16 | * | |
17 | * Changes: | |
18 | * A.N.Kuznetsov : airthmetics in fragmentation. | |
19 | * extension headers are implemented. | |
20 | * route changes now work. | |
21 | * ip6_forward does not confuse sniffers. | |
22 | * etc. | |
23 | * | |
24 | * H. von Brand : Added missing #include <linux/string.h> | |
25 | * Imran Patel : frag id should be in NBO | |
26 | * Kazunori MIYAZAWA @USAGI | |
27 | * : add ip6_append_data and related functions | |
28 | * for datagram xmit | |
29 | */ | |
30 | ||
1da177e4 | 31 | #include <linux/errno.h> |
ef76bc23 | 32 | #include <linux/kernel.h> |
1da177e4 LT |
33 | #include <linux/string.h> |
34 | #include <linux/socket.h> | |
35 | #include <linux/net.h> | |
36 | #include <linux/netdevice.h> | |
37 | #include <linux/if_arp.h> | |
38 | #include <linux/in6.h> | |
39 | #include <linux/tcp.h> | |
40 | #include <linux/route.h> | |
b59f45d0 | 41 | #include <linux/module.h> |
1da177e4 LT |
42 | |
43 | #include <linux/netfilter.h> | |
44 | #include <linux/netfilter_ipv6.h> | |
45 | ||
46 | #include <net/sock.h> | |
47 | #include <net/snmp.h> | |
48 | ||
49 | #include <net/ipv6.h> | |
50 | #include <net/ndisc.h> | |
51 | #include <net/protocol.h> | |
52 | #include <net/ip6_route.h> | |
53 | #include <net/addrconf.h> | |
54 | #include <net/rawv6.h> | |
55 | #include <net/icmp.h> | |
56 | #include <net/xfrm.h> | |
57 | #include <net/checksum.h> | |
58 | ||
59 | static int ip6_fragment(struct sk_buff *skb, int (*output)(struct sk_buff *)); | |
60 | ||
61 | static __inline__ void ipv6_select_ident(struct sk_buff *skb, struct frag_hdr *fhdr) | |
62 | { | |
63 | static u32 ipv6_fragmentation_id = 1; | |
64 | static DEFINE_SPINLOCK(ip6_id_lock); | |
65 | ||
66 | spin_lock_bh(&ip6_id_lock); | |
67 | fhdr->identification = htonl(ipv6_fragmentation_id); | |
68 | if (++ipv6_fragmentation_id == 0) | |
69 | ipv6_fragmentation_id = 1; | |
70 | spin_unlock_bh(&ip6_id_lock); | |
71 | } | |
72 | ||
ef76bc23 HX |
73 | int __ip6_local_out(struct sk_buff *skb) |
74 | { | |
75 | int len; | |
76 | ||
77 | len = skb->len - sizeof(struct ipv6hdr); | |
78 | if (len > IPV6_MAXPLEN) | |
79 | len = 0; | |
80 | ipv6_hdr(skb)->payload_len = htons(len); | |
81 | ||
82 | return nf_hook(PF_INET6, NF_IP6_LOCAL_OUT, skb, NULL, skb->dst->dev, | |
83 | dst_output); | |
84 | } | |
85 | ||
86 | int ip6_local_out(struct sk_buff *skb) | |
87 | { | |
88 | int err; | |
89 | ||
90 | err = __ip6_local_out(skb); | |
91 | if (likely(err == 1)) | |
92 | err = dst_output(skb); | |
93 | ||
94 | return err; | |
95 | } | |
96 | EXPORT_SYMBOL_GPL(ip6_local_out); | |
97 | ||
ad643a79 | 98 | static int ip6_output_finish(struct sk_buff *skb) |
1da177e4 | 99 | { |
1da177e4 | 100 | struct dst_entry *dst = skb->dst; |
1da177e4 | 101 | |
3644f0ce SH |
102 | if (dst->hh) |
103 | return neigh_hh_output(dst->hh, skb); | |
104 | else if (dst->neighbour) | |
1da177e4 LT |
105 | return dst->neighbour->output(skb); |
106 | ||
a11d206d | 107 | IP6_INC_STATS_BH(ip6_dst_idev(dst), IPSTATS_MIB_OUTNOROUTES); |
1da177e4 LT |
108 | kfree_skb(skb); |
109 | return -EINVAL; | |
110 | ||
111 | } | |
112 | ||
113 | /* dev_loopback_xmit for use with netfilter. */ | |
114 | static int ip6_dev_loopback_xmit(struct sk_buff *newskb) | |
115 | { | |
459a98ed | 116 | skb_reset_mac_header(newskb); |
bbe735e4 | 117 | __skb_pull(newskb, skb_network_offset(newskb)); |
1da177e4 LT |
118 | newskb->pkt_type = PACKET_LOOPBACK; |
119 | newskb->ip_summed = CHECKSUM_UNNECESSARY; | |
120 | BUG_TRAP(newskb->dst); | |
121 | ||
122 | netif_rx(newskb); | |
123 | return 0; | |
124 | } | |
125 | ||
126 | ||
127 | static int ip6_output2(struct sk_buff *skb) | |
128 | { | |
129 | struct dst_entry *dst = skb->dst; | |
130 | struct net_device *dev = dst->dev; | |
131 | ||
132 | skb->protocol = htons(ETH_P_IPV6); | |
133 | skb->dev = dev; | |
134 | ||
0660e03f | 135 | if (ipv6_addr_is_multicast(&ipv6_hdr(skb)->daddr)) { |
1da177e4 | 136 | struct ipv6_pinfo* np = skb->sk ? inet6_sk(skb->sk) : NULL; |
a11d206d | 137 | struct inet6_dev *idev = ip6_dst_idev(skb->dst); |
1da177e4 LT |
138 | |
139 | if (!(dev->flags & IFF_LOOPBACK) && (!np || np->mc_loop) && | |
0660e03f ACM |
140 | ipv6_chk_mcast_addr(dev, &ipv6_hdr(skb)->daddr, |
141 | &ipv6_hdr(skb)->saddr)) { | |
1da177e4 LT |
142 | struct sk_buff *newskb = skb_clone(skb, GFP_ATOMIC); |
143 | ||
144 | /* Do not check for IFF_ALLMULTI; multicast routing | |
145 | is not supported in any case. | |
146 | */ | |
147 | if (newskb) | |
148 | NF_HOOK(PF_INET6, NF_IP6_POST_ROUTING, newskb, NULL, | |
149 | newskb->dev, | |
150 | ip6_dev_loopback_xmit); | |
151 | ||
0660e03f | 152 | if (ipv6_hdr(skb)->hop_limit == 0) { |
a11d206d | 153 | IP6_INC_STATS(idev, IPSTATS_MIB_OUTDISCARDS); |
1da177e4 LT |
154 | kfree_skb(skb); |
155 | return 0; | |
156 | } | |
157 | } | |
158 | ||
a11d206d | 159 | IP6_INC_STATS(idev, IPSTATS_MIB_OUTMCASTPKTS); |
1da177e4 LT |
160 | } |
161 | ||
162 | return NF_HOOK(PF_INET6, NF_IP6_POST_ROUTING, skb,NULL, skb->dev,ip6_output_finish); | |
163 | } | |
164 | ||
628a5c56 JH |
165 | static inline int ip6_skb_dst_mtu(struct sk_buff *skb) |
166 | { | |
167 | struct ipv6_pinfo *np = skb->sk ? inet6_sk(skb->sk) : NULL; | |
168 | ||
169 | return (np && np->pmtudisc == IPV6_PMTUDISC_PROBE) ? | |
170 | skb->dst->dev->mtu : dst_mtu(skb->dst); | |
171 | } | |
172 | ||
1da177e4 LT |
173 | int ip6_output(struct sk_buff *skb) |
174 | { | |
628a5c56 | 175 | if ((skb->len > ip6_skb_dst_mtu(skb) && !skb_is_gso(skb)) || |
e89e9cf5 | 176 | dst_allfrag(skb->dst)) |
1da177e4 LT |
177 | return ip6_fragment(skb, ip6_output2); |
178 | else | |
179 | return ip6_output2(skb); | |
180 | } | |
181 | ||
1da177e4 LT |
182 | /* |
183 | * xmit an sk_buff (used by TCP) | |
184 | */ | |
185 | ||
186 | int ip6_xmit(struct sock *sk, struct sk_buff *skb, struct flowi *fl, | |
187 | struct ipv6_txoptions *opt, int ipfragok) | |
188 | { | |
b30bd282 | 189 | struct ipv6_pinfo *np = inet6_sk(sk); |
1da177e4 LT |
190 | struct in6_addr *first_hop = &fl->fl6_dst; |
191 | struct dst_entry *dst = skb->dst; | |
192 | struct ipv6hdr *hdr; | |
193 | u8 proto = fl->proto; | |
194 | int seg_len = skb->len; | |
41a1f8ea | 195 | int hlimit, tclass; |
1da177e4 LT |
196 | u32 mtu; |
197 | ||
198 | if (opt) { | |
c2636b4d | 199 | unsigned int head_room; |
1da177e4 LT |
200 | |
201 | /* First: exthdrs may take lots of space (~8K for now) | |
202 | MAX_HEADER is not enough. | |
203 | */ | |
204 | head_room = opt->opt_nflen + opt->opt_flen; | |
205 | seg_len += head_room; | |
206 | head_room += sizeof(struct ipv6hdr) + LL_RESERVED_SPACE(dst->dev); | |
207 | ||
208 | if (skb_headroom(skb) < head_room) { | |
209 | struct sk_buff *skb2 = skb_realloc_headroom(skb, head_room); | |
a11d206d YH |
210 | if (skb2 == NULL) { |
211 | IP6_INC_STATS(ip6_dst_idev(skb->dst), | |
212 | IPSTATS_MIB_OUTDISCARDS); | |
213 | kfree_skb(skb); | |
1da177e4 LT |
214 | return -ENOBUFS; |
215 | } | |
a11d206d YH |
216 | kfree_skb(skb); |
217 | skb = skb2; | |
1da177e4 LT |
218 | if (sk) |
219 | skb_set_owner_w(skb, sk); | |
220 | } | |
221 | if (opt->opt_flen) | |
222 | ipv6_push_frag_opts(skb, opt, &proto); | |
223 | if (opt->opt_nflen) | |
224 | ipv6_push_nfrag_opts(skb, opt, &proto, &first_hop); | |
225 | } | |
226 | ||
e2d1bca7 ACM |
227 | skb_push(skb, sizeof(struct ipv6hdr)); |
228 | skb_reset_network_header(skb); | |
0660e03f | 229 | hdr = ipv6_hdr(skb); |
1da177e4 LT |
230 | |
231 | /* | |
232 | * Fill in the IPv6 header | |
233 | */ | |
234 | ||
1da177e4 LT |
235 | hlimit = -1; |
236 | if (np) | |
237 | hlimit = np->hop_limit; | |
238 | if (hlimit < 0) | |
239 | hlimit = dst_metric(dst, RTAX_HOPLIMIT); | |
240 | if (hlimit < 0) | |
241 | hlimit = ipv6_get_hoplimit(dst->dev); | |
242 | ||
41a1f8ea YH |
243 | tclass = -1; |
244 | if (np) | |
245 | tclass = np->tclass; | |
246 | if (tclass < 0) | |
247 | tclass = 0; | |
248 | ||
90bcaf7b | 249 | *(__be32 *)hdr = htonl(0x60000000 | (tclass << 20)) | fl->fl6_flowlabel; |
41a1f8ea | 250 | |
1da177e4 LT |
251 | hdr->payload_len = htons(seg_len); |
252 | hdr->nexthdr = proto; | |
253 | hdr->hop_limit = hlimit; | |
254 | ||
255 | ipv6_addr_copy(&hdr->saddr, &fl->fl6_src); | |
256 | ipv6_addr_copy(&hdr->daddr, first_hop); | |
257 | ||
a2c2064f PM |
258 | skb->priority = sk->sk_priority; |
259 | ||
1da177e4 | 260 | mtu = dst_mtu(dst); |
89114afd | 261 | if ((skb->len <= mtu) || ipfragok || skb_is_gso(skb)) { |
a11d206d YH |
262 | IP6_INC_STATS(ip6_dst_idev(skb->dst), |
263 | IPSTATS_MIB_OUTREQUESTS); | |
6869c4d8 HW |
264 | return NF_HOOK(PF_INET6, NF_IP6_LOCAL_OUT, skb, NULL, dst->dev, |
265 | dst_output); | |
1da177e4 LT |
266 | } |
267 | ||
268 | if (net_ratelimit()) | |
269 | printk(KERN_DEBUG "IPv6: sending pkt_too_big to self\n"); | |
270 | skb->dev = dst->dev; | |
271 | icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu, skb->dev); | |
a11d206d | 272 | IP6_INC_STATS(ip6_dst_idev(skb->dst), IPSTATS_MIB_FRAGFAILS); |
1da177e4 LT |
273 | kfree_skb(skb); |
274 | return -EMSGSIZE; | |
275 | } | |
276 | ||
7159039a YH |
277 | EXPORT_SYMBOL(ip6_xmit); |
278 | ||
1da177e4 LT |
279 | /* |
280 | * To avoid extra problems ND packets are send through this | |
281 | * routine. It's code duplication but I really want to avoid | |
282 | * extra checks since ipv6_build_header is used by TCP (which | |
283 | * is for us performance critical) | |
284 | */ | |
285 | ||
286 | int ip6_nd_hdr(struct sock *sk, struct sk_buff *skb, struct net_device *dev, | |
287 | struct in6_addr *saddr, struct in6_addr *daddr, | |
288 | int proto, int len) | |
289 | { | |
290 | struct ipv6_pinfo *np = inet6_sk(sk); | |
291 | struct ipv6hdr *hdr; | |
292 | int totlen; | |
293 | ||
294 | skb->protocol = htons(ETH_P_IPV6); | |
295 | skb->dev = dev; | |
296 | ||
297 | totlen = len + sizeof(struct ipv6hdr); | |
298 | ||
55f79cc0 ACM |
299 | skb_reset_network_header(skb); |
300 | skb_put(skb, sizeof(struct ipv6hdr)); | |
0660e03f | 301 | hdr = ipv6_hdr(skb); |
1da177e4 | 302 | |
ae08e1f0 | 303 | *(__be32*)hdr = htonl(0x60000000); |
1da177e4 LT |
304 | |
305 | hdr->payload_len = htons(len); | |
306 | hdr->nexthdr = proto; | |
307 | hdr->hop_limit = np->hop_limit; | |
308 | ||
309 | ipv6_addr_copy(&hdr->saddr, saddr); | |
310 | ipv6_addr_copy(&hdr->daddr, daddr); | |
311 | ||
312 | return 0; | |
313 | } | |
314 | ||
315 | static int ip6_call_ra_chain(struct sk_buff *skb, int sel) | |
316 | { | |
317 | struct ip6_ra_chain *ra; | |
318 | struct sock *last = NULL; | |
319 | ||
320 | read_lock(&ip6_ra_lock); | |
321 | for (ra = ip6_ra_chain; ra; ra = ra->next) { | |
322 | struct sock *sk = ra->sk; | |
0bd1b59b AM |
323 | if (sk && ra->sel == sel && |
324 | (!sk->sk_bound_dev_if || | |
325 | sk->sk_bound_dev_if == skb->dev->ifindex)) { | |
1da177e4 LT |
326 | if (last) { |
327 | struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC); | |
328 | if (skb2) | |
329 | rawv6_rcv(last, skb2); | |
330 | } | |
331 | last = sk; | |
332 | } | |
333 | } | |
334 | ||
335 | if (last) { | |
336 | rawv6_rcv(last, skb); | |
337 | read_unlock(&ip6_ra_lock); | |
338 | return 1; | |
339 | } | |
340 | read_unlock(&ip6_ra_lock); | |
341 | return 0; | |
342 | } | |
343 | ||
e21e0b5f VN |
344 | static int ip6_forward_proxy_check(struct sk_buff *skb) |
345 | { | |
0660e03f | 346 | struct ipv6hdr *hdr = ipv6_hdr(skb); |
e21e0b5f VN |
347 | u8 nexthdr = hdr->nexthdr; |
348 | int offset; | |
349 | ||
350 | if (ipv6_ext_hdr(nexthdr)) { | |
351 | offset = ipv6_skip_exthdr(skb, sizeof(*hdr), &nexthdr); | |
352 | if (offset < 0) | |
353 | return 0; | |
354 | } else | |
355 | offset = sizeof(struct ipv6hdr); | |
356 | ||
357 | if (nexthdr == IPPROTO_ICMPV6) { | |
358 | struct icmp6hdr *icmp6; | |
359 | ||
d56f90a7 ACM |
360 | if (!pskb_may_pull(skb, (skb_network_header(skb) + |
361 | offset + 1 - skb->data))) | |
e21e0b5f VN |
362 | return 0; |
363 | ||
d56f90a7 | 364 | icmp6 = (struct icmp6hdr *)(skb_network_header(skb) + offset); |
e21e0b5f VN |
365 | |
366 | switch (icmp6->icmp6_type) { | |
367 | case NDISC_ROUTER_SOLICITATION: | |
368 | case NDISC_ROUTER_ADVERTISEMENT: | |
369 | case NDISC_NEIGHBOUR_SOLICITATION: | |
370 | case NDISC_NEIGHBOUR_ADVERTISEMENT: | |
371 | case NDISC_REDIRECT: | |
372 | /* For reaction involving unicast neighbor discovery | |
373 | * message destined to the proxied address, pass it to | |
374 | * input function. | |
375 | */ | |
376 | return 1; | |
377 | default: | |
378 | break; | |
379 | } | |
380 | } | |
381 | ||
74553b09 VN |
382 | /* |
383 | * The proxying router can't forward traffic sent to a link-local | |
384 | * address, so signal the sender and discard the packet. This | |
385 | * behavior is clarified by the MIPv6 specification. | |
386 | */ | |
387 | if (ipv6_addr_type(&hdr->daddr) & IPV6_ADDR_LINKLOCAL) { | |
388 | dst_link_failure(skb); | |
389 | return -1; | |
390 | } | |
391 | ||
e21e0b5f VN |
392 | return 0; |
393 | } | |
394 | ||
1da177e4 LT |
395 | static inline int ip6_forward_finish(struct sk_buff *skb) |
396 | { | |
397 | return dst_output(skb); | |
398 | } | |
399 | ||
400 | int ip6_forward(struct sk_buff *skb) | |
401 | { | |
402 | struct dst_entry *dst = skb->dst; | |
0660e03f | 403 | struct ipv6hdr *hdr = ipv6_hdr(skb); |
1da177e4 | 404 | struct inet6_skb_parm *opt = IP6CB(skb); |
1ab1457c | 405 | |
1da177e4 LT |
406 | if (ipv6_devconf.forwarding == 0) |
407 | goto error; | |
408 | ||
409 | if (!xfrm6_policy_check(NULL, XFRM_POLICY_FWD, skb)) { | |
a11d206d | 410 | IP6_INC_STATS(ip6_dst_idev(dst), IPSTATS_MIB_INDISCARDS); |
1da177e4 LT |
411 | goto drop; |
412 | } | |
413 | ||
35fc92a9 | 414 | skb_forward_csum(skb); |
1da177e4 LT |
415 | |
416 | /* | |
417 | * We DO NOT make any processing on | |
418 | * RA packets, pushing them to user level AS IS | |
419 | * without ane WARRANTY that application will be able | |
420 | * to interpret them. The reason is that we | |
421 | * cannot make anything clever here. | |
422 | * | |
423 | * We are not end-node, so that if packet contains | |
424 | * AH/ESP, we cannot make anything. | |
425 | * Defragmentation also would be mistake, RA packets | |
426 | * cannot be fragmented, because there is no warranty | |
427 | * that different fragments will go along one path. --ANK | |
428 | */ | |
429 | if (opt->ra) { | |
d56f90a7 | 430 | u8 *ptr = skb_network_header(skb) + opt->ra; |
1da177e4 LT |
431 | if (ip6_call_ra_chain(skb, (ptr[2]<<8) + ptr[3])) |
432 | return 0; | |
433 | } | |
434 | ||
435 | /* | |
436 | * check and decrement ttl | |
437 | */ | |
438 | if (hdr->hop_limit <= 1) { | |
439 | /* Force OUTPUT device used as source address */ | |
440 | skb->dev = dst->dev; | |
441 | icmpv6_send(skb, ICMPV6_TIME_EXCEED, ICMPV6_EXC_HOPLIMIT, | |
442 | 0, skb->dev); | |
a11d206d | 443 | IP6_INC_STATS_BH(ip6_dst_idev(dst), IPSTATS_MIB_INHDRERRORS); |
1da177e4 LT |
444 | |
445 | kfree_skb(skb); | |
446 | return -ETIMEDOUT; | |
447 | } | |
448 | ||
fbea49e1 YH |
449 | /* XXX: idev->cnf.proxy_ndp? */ |
450 | if (ipv6_devconf.proxy_ndp && | |
451 | pneigh_lookup(&nd_tbl, &hdr->daddr, skb->dev, 0)) { | |
74553b09 VN |
452 | int proxied = ip6_forward_proxy_check(skb); |
453 | if (proxied > 0) | |
e21e0b5f | 454 | return ip6_input(skb); |
74553b09 | 455 | else if (proxied < 0) { |
a11d206d | 456 | IP6_INC_STATS(ip6_dst_idev(dst), IPSTATS_MIB_INDISCARDS); |
74553b09 VN |
457 | goto drop; |
458 | } | |
e21e0b5f VN |
459 | } |
460 | ||
1da177e4 | 461 | if (!xfrm6_route_forward(skb)) { |
a11d206d | 462 | IP6_INC_STATS(ip6_dst_idev(dst), IPSTATS_MIB_INDISCARDS); |
1da177e4 LT |
463 | goto drop; |
464 | } | |
465 | dst = skb->dst; | |
466 | ||
467 | /* IPv6 specs say nothing about it, but it is clear that we cannot | |
468 | send redirects to source routed frames. | |
1e5dc146 | 469 | We don't send redirects to frames decapsulated from IPsec. |
1da177e4 | 470 | */ |
1e5dc146 MN |
471 | if (skb->dev == dst->dev && dst->neighbour && opt->srcrt == 0 && |
472 | !skb->sp) { | |
1da177e4 LT |
473 | struct in6_addr *target = NULL; |
474 | struct rt6_info *rt; | |
475 | struct neighbour *n = dst->neighbour; | |
476 | ||
477 | /* | |
478 | * incoming and outgoing devices are the same | |
479 | * send a redirect. | |
480 | */ | |
481 | ||
482 | rt = (struct rt6_info *) dst; | |
483 | if ((rt->rt6i_flags & RTF_GATEWAY)) | |
484 | target = (struct in6_addr*)&n->primary_key; | |
485 | else | |
486 | target = &hdr->daddr; | |
487 | ||
488 | /* Limit redirects both by destination (here) | |
489 | and by source (inside ndisc_send_redirect) | |
490 | */ | |
491 | if (xrlim_allow(dst, 1*HZ)) | |
492 | ndisc_send_redirect(skb, n, target); | |
5bb1ab09 DS |
493 | } else { |
494 | int addrtype = ipv6_addr_type(&hdr->saddr); | |
495 | ||
1da177e4 | 496 | /* This check is security critical. */ |
5bb1ab09 DS |
497 | if (addrtype & (IPV6_ADDR_MULTICAST|IPV6_ADDR_LOOPBACK)) |
498 | goto error; | |
499 | if (addrtype & IPV6_ADDR_LINKLOCAL) { | |
500 | icmpv6_send(skb, ICMPV6_DEST_UNREACH, | |
501 | ICMPV6_NOT_NEIGHBOUR, 0, skb->dev); | |
502 | goto error; | |
503 | } | |
1da177e4 LT |
504 | } |
505 | ||
506 | if (skb->len > dst_mtu(dst)) { | |
507 | /* Again, force OUTPUT device used as source address */ | |
508 | skb->dev = dst->dev; | |
509 | icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, dst_mtu(dst), skb->dev); | |
a11d206d YH |
510 | IP6_INC_STATS_BH(ip6_dst_idev(dst), IPSTATS_MIB_INTOOBIGERRORS); |
511 | IP6_INC_STATS_BH(ip6_dst_idev(dst), IPSTATS_MIB_FRAGFAILS); | |
1da177e4 LT |
512 | kfree_skb(skb); |
513 | return -EMSGSIZE; | |
514 | } | |
515 | ||
516 | if (skb_cow(skb, dst->dev->hard_header_len)) { | |
a11d206d | 517 | IP6_INC_STATS(ip6_dst_idev(dst), IPSTATS_MIB_OUTDISCARDS); |
1da177e4 LT |
518 | goto drop; |
519 | } | |
520 | ||
0660e03f | 521 | hdr = ipv6_hdr(skb); |
1da177e4 LT |
522 | |
523 | /* Mangling hops number delayed to point after skb COW */ | |
1ab1457c | 524 | |
1da177e4 LT |
525 | hdr->hop_limit--; |
526 | ||
a11d206d | 527 | IP6_INC_STATS_BH(ip6_dst_idev(dst), IPSTATS_MIB_OUTFORWDATAGRAMS); |
1da177e4 LT |
528 | return NF_HOOK(PF_INET6,NF_IP6_FORWARD, skb, skb->dev, dst->dev, ip6_forward_finish); |
529 | ||
530 | error: | |
a11d206d | 531 | IP6_INC_STATS_BH(ip6_dst_idev(dst), IPSTATS_MIB_INADDRERRORS); |
1da177e4 LT |
532 | drop: |
533 | kfree_skb(skb); | |
534 | return -EINVAL; | |
535 | } | |
536 | ||
537 | static void ip6_copy_metadata(struct sk_buff *to, struct sk_buff *from) | |
538 | { | |
539 | to->pkt_type = from->pkt_type; | |
540 | to->priority = from->priority; | |
541 | to->protocol = from->protocol; | |
1da177e4 LT |
542 | dst_release(to->dst); |
543 | to->dst = dst_clone(from->dst); | |
544 | to->dev = from->dev; | |
82e91ffe | 545 | to->mark = from->mark; |
1da177e4 LT |
546 | |
547 | #ifdef CONFIG_NET_SCHED | |
548 | to->tc_index = from->tc_index; | |
549 | #endif | |
e7ac05f3 | 550 | nf_copy(to, from); |
ba9dda3a JK |
551 | #if defined(CONFIG_NETFILTER_XT_TARGET_TRACE) || \ |
552 | defined(CONFIG_NETFILTER_XT_TARGET_TRACE_MODULE) | |
553 | to->nf_trace = from->nf_trace; | |
554 | #endif | |
984bc16c | 555 | skb_copy_secmark(to, from); |
1da177e4 LT |
556 | } |
557 | ||
558 | int ip6_find_1stfragopt(struct sk_buff *skb, u8 **nexthdr) | |
559 | { | |
560 | u16 offset = sizeof(struct ipv6hdr); | |
0660e03f ACM |
561 | struct ipv6_opt_hdr *exthdr = |
562 | (struct ipv6_opt_hdr *)(ipv6_hdr(skb) + 1); | |
27a884dc | 563 | unsigned int packet_len = skb->tail - skb->network_header; |
1da177e4 | 564 | int found_rhdr = 0; |
0660e03f | 565 | *nexthdr = &ipv6_hdr(skb)->nexthdr; |
1da177e4 LT |
566 | |
567 | while (offset + 1 <= packet_len) { | |
568 | ||
569 | switch (**nexthdr) { | |
570 | ||
571 | case NEXTHDR_HOP: | |
27637df9 | 572 | break; |
1da177e4 | 573 | case NEXTHDR_ROUTING: |
27637df9 MN |
574 | found_rhdr = 1; |
575 | break; | |
1da177e4 | 576 | case NEXTHDR_DEST: |
59fbb3a6 | 577 | #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE) |
27637df9 MN |
578 | if (ipv6_find_tlv(skb, offset, IPV6_TLV_HAO) >= 0) |
579 | break; | |
580 | #endif | |
581 | if (found_rhdr) | |
582 | return offset; | |
1da177e4 LT |
583 | break; |
584 | default : | |
585 | return offset; | |
586 | } | |
27637df9 MN |
587 | |
588 | offset += ipv6_optlen(exthdr); | |
589 | *nexthdr = &exthdr->nexthdr; | |
d56f90a7 ACM |
590 | exthdr = (struct ipv6_opt_hdr *)(skb_network_header(skb) + |
591 | offset); | |
1da177e4 LT |
592 | } |
593 | ||
594 | return offset; | |
595 | } | |
b59f45d0 | 596 | EXPORT_SYMBOL_GPL(ip6_find_1stfragopt); |
1da177e4 LT |
597 | |
598 | static int ip6_fragment(struct sk_buff *skb, int (*output)(struct sk_buff *)) | |
599 | { | |
600 | struct net_device *dev; | |
601 | struct sk_buff *frag; | |
602 | struct rt6_info *rt = (struct rt6_info*)skb->dst; | |
d91675f9 | 603 | struct ipv6_pinfo *np = skb->sk ? inet6_sk(skb->sk) : NULL; |
1da177e4 LT |
604 | struct ipv6hdr *tmp_hdr; |
605 | struct frag_hdr *fh; | |
606 | unsigned int mtu, hlen, left, len; | |
ae08e1f0 | 607 | __be32 frag_id = 0; |
1da177e4 LT |
608 | int ptr, offset = 0, err=0; |
609 | u8 *prevhdr, nexthdr = 0; | |
610 | ||
611 | dev = rt->u.dst.dev; | |
612 | hlen = ip6_find_1stfragopt(skb, &prevhdr); | |
613 | nexthdr = *prevhdr; | |
614 | ||
628a5c56 | 615 | mtu = ip6_skb_dst_mtu(skb); |
b881ef76 JH |
616 | |
617 | /* We must not fragment if the socket is set to force MTU discovery | |
618 | * or if the skb it not generated by a local socket. (This last | |
619 | * check should be redundant, but it's free.) | |
620 | */ | |
621 | if (!np || np->pmtudisc >= IPV6_PMTUDISC_DO) { | |
622 | skb->dev = skb->dst->dev; | |
623 | icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu, skb->dev); | |
624 | IP6_INC_STATS(ip6_dst_idev(skb->dst), IPSTATS_MIB_FRAGFAILS); | |
625 | kfree_skb(skb); | |
626 | return -EMSGSIZE; | |
627 | } | |
628 | ||
d91675f9 YH |
629 | if (np && np->frag_size < mtu) { |
630 | if (np->frag_size) | |
631 | mtu = np->frag_size; | |
632 | } | |
633 | mtu -= hlen + sizeof(struct frag_hdr); | |
1da177e4 LT |
634 | |
635 | if (skb_shinfo(skb)->frag_list) { | |
636 | int first_len = skb_pagelen(skb); | |
637 | ||
638 | if (first_len - hlen > mtu || | |
639 | ((first_len - hlen) & 7) || | |
640 | skb_cloned(skb)) | |
641 | goto slow_path; | |
642 | ||
643 | for (frag = skb_shinfo(skb)->frag_list; frag; frag = frag->next) { | |
644 | /* Correct geometry. */ | |
645 | if (frag->len > mtu || | |
646 | ((frag->len & 7) && frag->next) || | |
647 | skb_headroom(frag) < hlen) | |
648 | goto slow_path; | |
649 | ||
1da177e4 LT |
650 | /* Partially cloned skb? */ |
651 | if (skb_shared(frag)) | |
652 | goto slow_path; | |
2fdba6b0 HX |
653 | |
654 | BUG_ON(frag->sk); | |
655 | if (skb->sk) { | |
656 | sock_hold(skb->sk); | |
657 | frag->sk = skb->sk; | |
658 | frag->destructor = sock_wfree; | |
659 | skb->truesize -= frag->truesize; | |
660 | } | |
1da177e4 LT |
661 | } |
662 | ||
663 | err = 0; | |
664 | offset = 0; | |
665 | frag = skb_shinfo(skb)->frag_list; | |
666 | skb_shinfo(skb)->frag_list = NULL; | |
667 | /* BUILD HEADER */ | |
668 | ||
9a217a1c | 669 | *prevhdr = NEXTHDR_FRAGMENT; |
d56f90a7 | 670 | tmp_hdr = kmemdup(skb_network_header(skb), hlen, GFP_ATOMIC); |
1da177e4 | 671 | if (!tmp_hdr) { |
a11d206d | 672 | IP6_INC_STATS(ip6_dst_idev(skb->dst), IPSTATS_MIB_FRAGFAILS); |
1da177e4 LT |
673 | return -ENOMEM; |
674 | } | |
675 | ||
1da177e4 LT |
676 | __skb_pull(skb, hlen); |
677 | fh = (struct frag_hdr*)__skb_push(skb, sizeof(struct frag_hdr)); | |
e2d1bca7 ACM |
678 | __skb_push(skb, hlen); |
679 | skb_reset_network_header(skb); | |
d56f90a7 | 680 | memcpy(skb_network_header(skb), tmp_hdr, hlen); |
1da177e4 LT |
681 | |
682 | ipv6_select_ident(skb, fh); | |
683 | fh->nexthdr = nexthdr; | |
684 | fh->reserved = 0; | |
685 | fh->frag_off = htons(IP6_MF); | |
686 | frag_id = fh->identification; | |
687 | ||
688 | first_len = skb_pagelen(skb); | |
689 | skb->data_len = first_len - skb_headlen(skb); | |
690 | skb->len = first_len; | |
0660e03f ACM |
691 | ipv6_hdr(skb)->payload_len = htons(first_len - |
692 | sizeof(struct ipv6hdr)); | |
a11d206d YH |
693 | |
694 | dst_hold(&rt->u.dst); | |
1da177e4 LT |
695 | |
696 | for (;;) { | |
697 | /* Prepare header of the next frame, | |
698 | * before previous one went down. */ | |
699 | if (frag) { | |
700 | frag->ip_summed = CHECKSUM_NONE; | |
badff6d0 | 701 | skb_reset_transport_header(frag); |
1da177e4 | 702 | fh = (struct frag_hdr*)__skb_push(frag, sizeof(struct frag_hdr)); |
e2d1bca7 ACM |
703 | __skb_push(frag, hlen); |
704 | skb_reset_network_header(frag); | |
d56f90a7 ACM |
705 | memcpy(skb_network_header(frag), tmp_hdr, |
706 | hlen); | |
1da177e4 LT |
707 | offset += skb->len - hlen - sizeof(struct frag_hdr); |
708 | fh->nexthdr = nexthdr; | |
709 | fh->reserved = 0; | |
710 | fh->frag_off = htons(offset); | |
711 | if (frag->next != NULL) | |
712 | fh->frag_off |= htons(IP6_MF); | |
713 | fh->identification = frag_id; | |
0660e03f ACM |
714 | ipv6_hdr(frag)->payload_len = |
715 | htons(frag->len - | |
716 | sizeof(struct ipv6hdr)); | |
1da177e4 LT |
717 | ip6_copy_metadata(frag, skb); |
718 | } | |
1ab1457c | 719 | |
1da177e4 | 720 | err = output(skb); |
dafee490 | 721 | if(!err) |
a11d206d | 722 | IP6_INC_STATS(ip6_dst_idev(&rt->u.dst), IPSTATS_MIB_FRAGCREATES); |
dafee490 | 723 | |
1da177e4 LT |
724 | if (err || !frag) |
725 | break; | |
726 | ||
727 | skb = frag; | |
728 | frag = skb->next; | |
729 | skb->next = NULL; | |
730 | } | |
731 | ||
a51482bd | 732 | kfree(tmp_hdr); |
1da177e4 LT |
733 | |
734 | if (err == 0) { | |
a11d206d YH |
735 | IP6_INC_STATS(ip6_dst_idev(&rt->u.dst), IPSTATS_MIB_FRAGOKS); |
736 | dst_release(&rt->u.dst); | |
1da177e4 LT |
737 | return 0; |
738 | } | |
739 | ||
740 | while (frag) { | |
741 | skb = frag->next; | |
742 | kfree_skb(frag); | |
743 | frag = skb; | |
744 | } | |
745 | ||
a11d206d YH |
746 | IP6_INC_STATS(ip6_dst_idev(&rt->u.dst), IPSTATS_MIB_FRAGFAILS); |
747 | dst_release(&rt->u.dst); | |
1da177e4 LT |
748 | return err; |
749 | } | |
750 | ||
751 | slow_path: | |
752 | left = skb->len - hlen; /* Space per frame */ | |
753 | ptr = hlen; /* Where to start from */ | |
754 | ||
755 | /* | |
756 | * Fragment the datagram. | |
757 | */ | |
758 | ||
759 | *prevhdr = NEXTHDR_FRAGMENT; | |
760 | ||
761 | /* | |
762 | * Keep copying data until we run out. | |
763 | */ | |
764 | while(left > 0) { | |
765 | len = left; | |
766 | /* IF: it doesn't fit, use 'mtu' - the data space left */ | |
767 | if (len > mtu) | |
768 | len = mtu; | |
769 | /* IF: we are not sending upto and including the packet end | |
770 | then align the next start on an eight byte boundary */ | |
771 | if (len < left) { | |
772 | len &= ~7; | |
773 | } | |
774 | /* | |
775 | * Allocate buffer. | |
776 | */ | |
777 | ||
778 | if ((frag = alloc_skb(len+hlen+sizeof(struct frag_hdr)+LL_RESERVED_SPACE(rt->u.dst.dev), GFP_ATOMIC)) == NULL) { | |
64ce2073 | 779 | NETDEBUG(KERN_INFO "IPv6: frag: no memory for new fragment!\n"); |
a11d206d YH |
780 | IP6_INC_STATS(ip6_dst_idev(skb->dst), |
781 | IPSTATS_MIB_FRAGFAILS); | |
1da177e4 LT |
782 | err = -ENOMEM; |
783 | goto fail; | |
784 | } | |
785 | ||
786 | /* | |
787 | * Set up data on packet | |
788 | */ | |
789 | ||
790 | ip6_copy_metadata(frag, skb); | |
791 | skb_reserve(frag, LL_RESERVED_SPACE(rt->u.dst.dev)); | |
792 | skb_put(frag, len + hlen + sizeof(struct frag_hdr)); | |
c1d2bbe1 | 793 | skb_reset_network_header(frag); |
badff6d0 | 794 | fh = (struct frag_hdr *)(skb_network_header(frag) + hlen); |
b0e380b1 ACM |
795 | frag->transport_header = (frag->network_header + hlen + |
796 | sizeof(struct frag_hdr)); | |
1da177e4 LT |
797 | |
798 | /* | |
799 | * Charge the memory for the fragment to any owner | |
800 | * it might possess | |
801 | */ | |
802 | if (skb->sk) | |
803 | skb_set_owner_w(frag, skb->sk); | |
804 | ||
805 | /* | |
806 | * Copy the packet header into the new buffer. | |
807 | */ | |
d626f62b | 808 | skb_copy_from_linear_data(skb, skb_network_header(frag), hlen); |
1da177e4 LT |
809 | |
810 | /* | |
811 | * Build fragment header. | |
812 | */ | |
813 | fh->nexthdr = nexthdr; | |
814 | fh->reserved = 0; | |
f36d6ab1 | 815 | if (!frag_id) { |
1da177e4 LT |
816 | ipv6_select_ident(skb, fh); |
817 | frag_id = fh->identification; | |
818 | } else | |
819 | fh->identification = frag_id; | |
820 | ||
821 | /* | |
822 | * Copy a block of the IP datagram. | |
823 | */ | |
8984e41d | 824 | if (skb_copy_bits(skb, ptr, skb_transport_header(frag), len)) |
1da177e4 LT |
825 | BUG(); |
826 | left -= len; | |
827 | ||
828 | fh->frag_off = htons(offset); | |
829 | if (left > 0) | |
830 | fh->frag_off |= htons(IP6_MF); | |
0660e03f ACM |
831 | ipv6_hdr(frag)->payload_len = htons(frag->len - |
832 | sizeof(struct ipv6hdr)); | |
1da177e4 LT |
833 | |
834 | ptr += len; | |
835 | offset += len; | |
836 | ||
837 | /* | |
838 | * Put this fragment into the sending queue. | |
839 | */ | |
1da177e4 LT |
840 | err = output(frag); |
841 | if (err) | |
842 | goto fail; | |
dafee490 | 843 | |
a11d206d | 844 | IP6_INC_STATS(ip6_dst_idev(skb->dst), IPSTATS_MIB_FRAGCREATES); |
1da177e4 | 845 | } |
a11d206d YH |
846 | IP6_INC_STATS(ip6_dst_idev(skb->dst), |
847 | IPSTATS_MIB_FRAGOKS); | |
1da177e4 | 848 | kfree_skb(skb); |
1da177e4 LT |
849 | return err; |
850 | ||
851 | fail: | |
a11d206d YH |
852 | IP6_INC_STATS(ip6_dst_idev(skb->dst), |
853 | IPSTATS_MIB_FRAGFAILS); | |
1ab1457c | 854 | kfree_skb(skb); |
1da177e4 LT |
855 | return err; |
856 | } | |
857 | ||
cf6b1982 YH |
858 | static inline int ip6_rt_check(struct rt6key *rt_key, |
859 | struct in6_addr *fl_addr, | |
860 | struct in6_addr *addr_cache) | |
861 | { | |
862 | return ((rt_key->plen != 128 || !ipv6_addr_equal(fl_addr, &rt_key->addr)) && | |
863 | (addr_cache == NULL || !ipv6_addr_equal(fl_addr, addr_cache))); | |
864 | } | |
865 | ||
497c615a HX |
866 | static struct dst_entry *ip6_sk_dst_check(struct sock *sk, |
867 | struct dst_entry *dst, | |
868 | struct flowi *fl) | |
1da177e4 | 869 | { |
497c615a HX |
870 | struct ipv6_pinfo *np = inet6_sk(sk); |
871 | struct rt6_info *rt = (struct rt6_info *)dst; | |
1da177e4 | 872 | |
497c615a HX |
873 | if (!dst) |
874 | goto out; | |
875 | ||
876 | /* Yes, checking route validity in not connected | |
877 | * case is not very simple. Take into account, | |
878 | * that we do not support routing by source, TOS, | |
879 | * and MSG_DONTROUTE --ANK (980726) | |
880 | * | |
cf6b1982 YH |
881 | * 1. ip6_rt_check(): If route was host route, |
882 | * check that cached destination is current. | |
497c615a HX |
883 | * If it is network route, we still may |
884 | * check its validity using saved pointer | |
885 | * to the last used address: daddr_cache. | |
886 | * We do not want to save whole address now, | |
887 | * (because main consumer of this service | |
888 | * is tcp, which has not this problem), | |
889 | * so that the last trick works only on connected | |
890 | * sockets. | |
891 | * 2. oif also should be the same. | |
892 | */ | |
cf6b1982 | 893 | if (ip6_rt_check(&rt->rt6i_dst, &fl->fl6_dst, np->daddr_cache) || |
8e1ef0a9 YH |
894 | #ifdef CONFIG_IPV6_SUBTREES |
895 | ip6_rt_check(&rt->rt6i_src, &fl->fl6_src, np->saddr_cache) || | |
896 | #endif | |
cf6b1982 | 897 | (fl->oif && fl->oif != dst->dev->ifindex)) { |
497c615a HX |
898 | dst_release(dst); |
899 | dst = NULL; | |
1da177e4 LT |
900 | } |
901 | ||
497c615a HX |
902 | out: |
903 | return dst; | |
904 | } | |
905 | ||
906 | static int ip6_dst_lookup_tail(struct sock *sk, | |
907 | struct dst_entry **dst, struct flowi *fl) | |
908 | { | |
909 | int err; | |
910 | ||
1da177e4 LT |
911 | if (*dst == NULL) |
912 | *dst = ip6_route_output(sk, fl); | |
913 | ||
914 | if ((err = (*dst)->error)) | |
915 | goto out_err_release; | |
916 | ||
917 | if (ipv6_addr_any(&fl->fl6_src)) { | |
918 | err = ipv6_get_saddr(*dst, &fl->fl6_dst, &fl->fl6_src); | |
44456d37 | 919 | if (err) |
1da177e4 | 920 | goto out_err_release; |
1da177e4 LT |
921 | } |
922 | ||
95c385b4 NH |
923 | #ifdef CONFIG_IPV6_OPTIMISTIC_DAD |
924 | /* | |
925 | * Here if the dst entry we've looked up | |
926 | * has a neighbour entry that is in the INCOMPLETE | |
927 | * state and the src address from the flow is | |
928 | * marked as OPTIMISTIC, we release the found | |
929 | * dst entry and replace it instead with the | |
930 | * dst entry of the nexthop router | |
931 | */ | |
932 | if (!((*dst)->neighbour->nud_state & NUD_VALID)) { | |
933 | struct inet6_ifaddr *ifp; | |
934 | struct flowi fl_gw; | |
935 | int redirect; | |
936 | ||
937 | ifp = ipv6_get_ifaddr(&fl->fl6_src, (*dst)->dev, 1); | |
938 | ||
939 | redirect = (ifp && ifp->flags & IFA_F_OPTIMISTIC); | |
940 | if (ifp) | |
941 | in6_ifa_put(ifp); | |
942 | ||
943 | if (redirect) { | |
944 | /* | |
945 | * We need to get the dst entry for the | |
946 | * default router instead | |
947 | */ | |
948 | dst_release(*dst); | |
949 | memcpy(&fl_gw, fl, sizeof(struct flowi)); | |
950 | memset(&fl_gw.fl6_dst, 0, sizeof(struct in6_addr)); | |
951 | *dst = ip6_route_output(sk, &fl_gw); | |
952 | if ((err = (*dst)->error)) | |
953 | goto out_err_release; | |
954 | } | |
955 | } | |
956 | #endif | |
957 | ||
1da177e4 LT |
958 | return 0; |
959 | ||
960 | out_err_release: | |
ca46f9c8 MC |
961 | if (err == -ENETUNREACH) |
962 | IP6_INC_STATS_BH(NULL, IPSTATS_MIB_OUTNOROUTES); | |
1da177e4 LT |
963 | dst_release(*dst); |
964 | *dst = NULL; | |
965 | return err; | |
966 | } | |
34a0b3cd | 967 | |
497c615a HX |
968 | /** |
969 | * ip6_dst_lookup - perform route lookup on flow | |
970 | * @sk: socket which provides route info | |
971 | * @dst: pointer to dst_entry * for result | |
972 | * @fl: flow to lookup | |
973 | * | |
974 | * This function performs a route lookup on the given flow. | |
975 | * | |
976 | * It returns zero on success, or a standard errno code on error. | |
977 | */ | |
978 | int ip6_dst_lookup(struct sock *sk, struct dst_entry **dst, struct flowi *fl) | |
979 | { | |
980 | *dst = NULL; | |
981 | return ip6_dst_lookup_tail(sk, dst, fl); | |
982 | } | |
3cf3dc6c ACM |
983 | EXPORT_SYMBOL_GPL(ip6_dst_lookup); |
984 | ||
497c615a HX |
985 | /** |
986 | * ip6_sk_dst_lookup - perform socket cached route lookup on flow | |
987 | * @sk: socket which provides the dst cache and route info | |
988 | * @dst: pointer to dst_entry * for result | |
989 | * @fl: flow to lookup | |
990 | * | |
991 | * This function performs a route lookup on the given flow with the | |
992 | * possibility of using the cached route in the socket if it is valid. | |
993 | * It will take the socket dst lock when operating on the dst cache. | |
994 | * As a result, this function can only be used in process context. | |
995 | * | |
996 | * It returns zero on success, or a standard errno code on error. | |
997 | */ | |
998 | int ip6_sk_dst_lookup(struct sock *sk, struct dst_entry **dst, struct flowi *fl) | |
999 | { | |
1000 | *dst = NULL; | |
1001 | if (sk) { | |
1002 | *dst = sk_dst_check(sk, inet6_sk(sk)->dst_cookie); | |
1003 | *dst = ip6_sk_dst_check(sk, *dst, fl); | |
1004 | } | |
1005 | ||
1006 | return ip6_dst_lookup_tail(sk, dst, fl); | |
1007 | } | |
1008 | EXPORT_SYMBOL_GPL(ip6_sk_dst_lookup); | |
1009 | ||
34a0b3cd | 1010 | static inline int ip6_ufo_append_data(struct sock *sk, |
e89e9cf5 AR |
1011 | int getfrag(void *from, char *to, int offset, int len, |
1012 | int odd, struct sk_buff *skb), | |
1013 | void *from, int length, int hh_len, int fragheaderlen, | |
1014 | int transhdrlen, int mtu,unsigned int flags) | |
1015 | ||
1016 | { | |
1017 | struct sk_buff *skb; | |
1018 | int err; | |
1019 | ||
1020 | /* There is support for UDP large send offload by network | |
1021 | * device, so create one single skb packet containing complete | |
1022 | * udp datagram | |
1023 | */ | |
1024 | if ((skb = skb_peek_tail(&sk->sk_write_queue)) == NULL) { | |
1025 | skb = sock_alloc_send_skb(sk, | |
1026 | hh_len + fragheaderlen + transhdrlen + 20, | |
1027 | (flags & MSG_DONTWAIT), &err); | |
1028 | if (skb == NULL) | |
1029 | return -ENOMEM; | |
1030 | ||
1031 | /* reserve space for Hardware header */ | |
1032 | skb_reserve(skb, hh_len); | |
1033 | ||
1034 | /* create space for UDP/IP header */ | |
1035 | skb_put(skb,fragheaderlen + transhdrlen); | |
1036 | ||
1037 | /* initialize network header pointer */ | |
c1d2bbe1 | 1038 | skb_reset_network_header(skb); |
e89e9cf5 AR |
1039 | |
1040 | /* initialize protocol header pointer */ | |
b0e380b1 | 1041 | skb->transport_header = skb->network_header + fragheaderlen; |
e89e9cf5 | 1042 | |
84fa7933 | 1043 | skb->ip_summed = CHECKSUM_PARTIAL; |
e89e9cf5 AR |
1044 | skb->csum = 0; |
1045 | sk->sk_sndmsg_off = 0; | |
1046 | } | |
1047 | ||
1048 | err = skb_append_datato_frags(sk,skb, getfrag, from, | |
1049 | (length - transhdrlen)); | |
1050 | if (!err) { | |
1051 | struct frag_hdr fhdr; | |
1052 | ||
1053 | /* specify the length of each IP datagram fragment*/ | |
1ab1457c | 1054 | skb_shinfo(skb)->gso_size = mtu - fragheaderlen - |
7967168c | 1055 | sizeof(struct frag_hdr); |
f83ef8c0 | 1056 | skb_shinfo(skb)->gso_type = SKB_GSO_UDP; |
e89e9cf5 AR |
1057 | ipv6_select_ident(skb, &fhdr); |
1058 | skb_shinfo(skb)->ip6_frag_id = fhdr.identification; | |
1059 | __skb_queue_tail(&sk->sk_write_queue, skb); | |
1060 | ||
1061 | return 0; | |
1062 | } | |
1063 | /* There is not enough support do UPD LSO, | |
1064 | * so follow normal path | |
1065 | */ | |
1066 | kfree_skb(skb); | |
1067 | ||
1068 | return err; | |
1069 | } | |
1da177e4 | 1070 | |
41a1f8ea YH |
1071 | int ip6_append_data(struct sock *sk, int getfrag(void *from, char *to, |
1072 | int offset, int len, int odd, struct sk_buff *skb), | |
1073 | void *from, int length, int transhdrlen, | |
1074 | int hlimit, int tclass, struct ipv6_txoptions *opt, struct flowi *fl, | |
1075 | struct rt6_info *rt, unsigned int flags) | |
1da177e4 LT |
1076 | { |
1077 | struct inet_sock *inet = inet_sk(sk); | |
1078 | struct ipv6_pinfo *np = inet6_sk(sk); | |
1079 | struct sk_buff *skb; | |
1080 | unsigned int maxfraglen, fragheaderlen; | |
1081 | int exthdrlen; | |
1082 | int hh_len; | |
1083 | int mtu; | |
1084 | int copy; | |
1085 | int err; | |
1086 | int offset = 0; | |
1087 | int csummode = CHECKSUM_NONE; | |
1088 | ||
1089 | if (flags&MSG_PROBE) | |
1090 | return 0; | |
1091 | if (skb_queue_empty(&sk->sk_write_queue)) { | |
1092 | /* | |
1093 | * setup for corking | |
1094 | */ | |
1095 | if (opt) { | |
1096 | if (np->cork.opt == NULL) { | |
1097 | np->cork.opt = kmalloc(opt->tot_len, | |
1098 | sk->sk_allocation); | |
1099 | if (unlikely(np->cork.opt == NULL)) | |
1100 | return -ENOBUFS; | |
1101 | } else if (np->cork.opt->tot_len < opt->tot_len) { | |
1102 | printk(KERN_DEBUG "ip6_append_data: invalid option length\n"); | |
1103 | return -EINVAL; | |
1104 | } | |
1105 | memcpy(np->cork.opt, opt, opt->tot_len); | |
1106 | inet->cork.flags |= IPCORK_OPT; | |
1107 | /* need source address above miyazawa*/ | |
1108 | } | |
1109 | dst_hold(&rt->u.dst); | |
1110 | np->cork.rt = rt; | |
1111 | inet->cork.fl = *fl; | |
1112 | np->cork.hop_limit = hlimit; | |
41a1f8ea | 1113 | np->cork.tclass = tclass; |
628a5c56 JH |
1114 | mtu = np->pmtudisc == IPV6_PMTUDISC_PROBE ? |
1115 | rt->u.dst.dev->mtu : dst_mtu(rt->u.dst.path); | |
c7503609 | 1116 | if (np->frag_size < mtu) { |
d91675f9 YH |
1117 | if (np->frag_size) |
1118 | mtu = np->frag_size; | |
1119 | } | |
1120 | inet->cork.fragsize = mtu; | |
1da177e4 LT |
1121 | if (dst_allfrag(rt->u.dst.path)) |
1122 | inet->cork.flags |= IPCORK_ALLFRAG; | |
1123 | inet->cork.length = 0; | |
1124 | sk->sk_sndmsg_page = NULL; | |
1125 | sk->sk_sndmsg_off = 0; | |
01488942 | 1126 | exthdrlen = rt->u.dst.header_len + (opt ? opt->opt_flen : 0) - |
b4ce9277 | 1127 | rt->nfheader_len; |
1da177e4 LT |
1128 | length += exthdrlen; |
1129 | transhdrlen += exthdrlen; | |
1130 | } else { | |
1131 | rt = np->cork.rt; | |
1132 | fl = &inet->cork.fl; | |
1133 | if (inet->cork.flags & IPCORK_OPT) | |
1134 | opt = np->cork.opt; | |
1135 | transhdrlen = 0; | |
1136 | exthdrlen = 0; | |
1137 | mtu = inet->cork.fragsize; | |
1138 | } | |
1139 | ||
1140 | hh_len = LL_RESERVED_SPACE(rt->u.dst.dev); | |
1141 | ||
b4ce9277 HX |
1142 | fragheaderlen = sizeof(struct ipv6hdr) + rt->nfheader_len + |
1143 | (opt ? opt->opt_nflen : 0); | |
1da177e4 LT |
1144 | maxfraglen = ((mtu - fragheaderlen) & ~7) + fragheaderlen - sizeof(struct frag_hdr); |
1145 | ||
1146 | if (mtu <= sizeof(struct ipv6hdr) + IPV6_MAXPLEN) { | |
1147 | if (inet->cork.length + length > sizeof(struct ipv6hdr) + IPV6_MAXPLEN - fragheaderlen) { | |
1148 | ipv6_local_error(sk, EMSGSIZE, fl, mtu-exthdrlen); | |
1149 | return -EMSGSIZE; | |
1150 | } | |
1151 | } | |
1152 | ||
1153 | /* | |
1154 | * Let's try using as much space as possible. | |
1155 | * Use MTU if total length of the message fits into the MTU. | |
1156 | * Otherwise, we need to reserve fragment header and | |
1157 | * fragment alignment (= 8-15 octects, in total). | |
1158 | * | |
1159 | * Note that we may need to "move" the data from the tail of | |
1ab1457c | 1160 | * of the buffer to the new fragment when we split |
1da177e4 LT |
1161 | * the message. |
1162 | * | |
1ab1457c | 1163 | * FIXME: It may be fragmented into multiple chunks |
1da177e4 LT |
1164 | * at once if non-fragmentable extension headers |
1165 | * are too large. | |
1ab1457c | 1166 | * --yoshfuji |
1da177e4 LT |
1167 | */ |
1168 | ||
1169 | inet->cork.length += length; | |
e89e9cf5 AR |
1170 | if (((length > mtu) && (sk->sk_protocol == IPPROTO_UDP)) && |
1171 | (rt->u.dst.dev->features & NETIF_F_UFO)) { | |
1172 | ||
baa829d8 PM |
1173 | err = ip6_ufo_append_data(sk, getfrag, from, length, hh_len, |
1174 | fragheaderlen, transhdrlen, mtu, | |
1175 | flags); | |
1176 | if (err) | |
e89e9cf5 | 1177 | goto error; |
e89e9cf5 AR |
1178 | return 0; |
1179 | } | |
1da177e4 LT |
1180 | |
1181 | if ((skb = skb_peek_tail(&sk->sk_write_queue)) == NULL) | |
1182 | goto alloc_new_skb; | |
1183 | ||
1184 | while (length > 0) { | |
1185 | /* Check if the remaining data fits into current packet. */ | |
1186 | copy = (inet->cork.length <= mtu && !(inet->cork.flags & IPCORK_ALLFRAG) ? mtu : maxfraglen) - skb->len; | |
1187 | if (copy < length) | |
1188 | copy = maxfraglen - skb->len; | |
1189 | ||
1190 | if (copy <= 0) { | |
1191 | char *data; | |
1192 | unsigned int datalen; | |
1193 | unsigned int fraglen; | |
1194 | unsigned int fraggap; | |
1195 | unsigned int alloclen; | |
1196 | struct sk_buff *skb_prev; | |
1197 | alloc_new_skb: | |
1198 | skb_prev = skb; | |
1199 | ||
1200 | /* There's no room in the current skb */ | |
1201 | if (skb_prev) | |
1202 | fraggap = skb_prev->len - maxfraglen; | |
1203 | else | |
1204 | fraggap = 0; | |
1205 | ||
1206 | /* | |
1207 | * If remaining data exceeds the mtu, | |
1208 | * we know we need more fragment(s). | |
1209 | */ | |
1210 | datalen = length + fraggap; | |
1211 | if (datalen > (inet->cork.length <= mtu && !(inet->cork.flags & IPCORK_ALLFRAG) ? mtu : maxfraglen) - fragheaderlen) | |
1212 | datalen = maxfraglen - fragheaderlen; | |
1213 | ||
1214 | fraglen = datalen + fragheaderlen; | |
1215 | if ((flags & MSG_MORE) && | |
1216 | !(rt->u.dst.dev->features&NETIF_F_SG)) | |
1217 | alloclen = mtu; | |
1218 | else | |
1219 | alloclen = datalen + fragheaderlen; | |
1220 | ||
1221 | /* | |
1222 | * The last fragment gets additional space at tail. | |
1223 | * Note: we overallocate on fragments with MSG_MODE | |
1224 | * because we have no idea if we're the last one. | |
1225 | */ | |
1226 | if (datalen == length + fraggap) | |
1227 | alloclen += rt->u.dst.trailer_len; | |
1228 | ||
1229 | /* | |
1230 | * We just reserve space for fragment header. | |
1ab1457c | 1231 | * Note: this may be overallocation if the message |
1da177e4 LT |
1232 | * (without MSG_MORE) fits into the MTU. |
1233 | */ | |
1234 | alloclen += sizeof(struct frag_hdr); | |
1235 | ||
1236 | if (transhdrlen) { | |
1237 | skb = sock_alloc_send_skb(sk, | |
1238 | alloclen + hh_len, | |
1239 | (flags & MSG_DONTWAIT), &err); | |
1240 | } else { | |
1241 | skb = NULL; | |
1242 | if (atomic_read(&sk->sk_wmem_alloc) <= | |
1243 | 2 * sk->sk_sndbuf) | |
1244 | skb = sock_wmalloc(sk, | |
1245 | alloclen + hh_len, 1, | |
1246 | sk->sk_allocation); | |
1247 | if (unlikely(skb == NULL)) | |
1248 | err = -ENOBUFS; | |
1249 | } | |
1250 | if (skb == NULL) | |
1251 | goto error; | |
1252 | /* | |
1253 | * Fill in the control structures | |
1254 | */ | |
1255 | skb->ip_summed = csummode; | |
1256 | skb->csum = 0; | |
1257 | /* reserve for fragmentation */ | |
1258 | skb_reserve(skb, hh_len+sizeof(struct frag_hdr)); | |
1259 | ||
1260 | /* | |
1261 | * Find where to start putting bytes | |
1262 | */ | |
1263 | data = skb_put(skb, fraglen); | |
c14d2450 | 1264 | skb_set_network_header(skb, exthdrlen); |
1da177e4 | 1265 | data += fragheaderlen; |
b0e380b1 ACM |
1266 | skb->transport_header = (skb->network_header + |
1267 | fragheaderlen); | |
1da177e4 LT |
1268 | if (fraggap) { |
1269 | skb->csum = skb_copy_and_csum_bits( | |
1270 | skb_prev, maxfraglen, | |
1271 | data + transhdrlen, fraggap, 0); | |
1272 | skb_prev->csum = csum_sub(skb_prev->csum, | |
1273 | skb->csum); | |
1274 | data += fraggap; | |
e9fa4f7b | 1275 | pskb_trim_unique(skb_prev, maxfraglen); |
1da177e4 LT |
1276 | } |
1277 | copy = datalen - transhdrlen - fraggap; | |
1278 | if (copy < 0) { | |
1279 | err = -EINVAL; | |
1280 | kfree_skb(skb); | |
1281 | goto error; | |
1282 | } else if (copy > 0 && getfrag(from, data + transhdrlen, offset, copy, fraggap, skb) < 0) { | |
1283 | err = -EFAULT; | |
1284 | kfree_skb(skb); | |
1285 | goto error; | |
1286 | } | |
1287 | ||
1288 | offset += copy; | |
1289 | length -= datalen - fraggap; | |
1290 | transhdrlen = 0; | |
1291 | exthdrlen = 0; | |
1292 | csummode = CHECKSUM_NONE; | |
1293 | ||
1294 | /* | |
1295 | * Put the packet on the pending queue | |
1296 | */ | |
1297 | __skb_queue_tail(&sk->sk_write_queue, skb); | |
1298 | continue; | |
1299 | } | |
1300 | ||
1301 | if (copy > length) | |
1302 | copy = length; | |
1303 | ||
1304 | if (!(rt->u.dst.dev->features&NETIF_F_SG)) { | |
1305 | unsigned int off; | |
1306 | ||
1307 | off = skb->len; | |
1308 | if (getfrag(from, skb_put(skb, copy), | |
1309 | offset, copy, off, skb) < 0) { | |
1310 | __skb_trim(skb, off); | |
1311 | err = -EFAULT; | |
1312 | goto error; | |
1313 | } | |
1314 | } else { | |
1315 | int i = skb_shinfo(skb)->nr_frags; | |
1316 | skb_frag_t *frag = &skb_shinfo(skb)->frags[i-1]; | |
1317 | struct page *page = sk->sk_sndmsg_page; | |
1318 | int off = sk->sk_sndmsg_off; | |
1319 | unsigned int left; | |
1320 | ||
1321 | if (page && (left = PAGE_SIZE - off) > 0) { | |
1322 | if (copy >= left) | |
1323 | copy = left; | |
1324 | if (page != frag->page) { | |
1325 | if (i == MAX_SKB_FRAGS) { | |
1326 | err = -EMSGSIZE; | |
1327 | goto error; | |
1328 | } | |
1329 | get_page(page); | |
1330 | skb_fill_page_desc(skb, i, page, sk->sk_sndmsg_off, 0); | |
1331 | frag = &skb_shinfo(skb)->frags[i]; | |
1332 | } | |
1333 | } else if(i < MAX_SKB_FRAGS) { | |
1334 | if (copy > PAGE_SIZE) | |
1335 | copy = PAGE_SIZE; | |
1336 | page = alloc_pages(sk->sk_allocation, 0); | |
1337 | if (page == NULL) { | |
1338 | err = -ENOMEM; | |
1339 | goto error; | |
1340 | } | |
1341 | sk->sk_sndmsg_page = page; | |
1342 | sk->sk_sndmsg_off = 0; | |
1343 | ||
1344 | skb_fill_page_desc(skb, i, page, 0, 0); | |
1345 | frag = &skb_shinfo(skb)->frags[i]; | |
1da177e4 LT |
1346 | } else { |
1347 | err = -EMSGSIZE; | |
1348 | goto error; | |
1349 | } | |
1350 | if (getfrag(from, page_address(frag->page)+frag->page_offset+frag->size, offset, copy, skb->len, skb) < 0) { | |
1351 | err = -EFAULT; | |
1352 | goto error; | |
1353 | } | |
1354 | sk->sk_sndmsg_off += copy; | |
1355 | frag->size += copy; | |
1356 | skb->len += copy; | |
1357 | skb->data_len += copy; | |
f945fa7a HX |
1358 | skb->truesize += copy; |
1359 | atomic_add(copy, &sk->sk_wmem_alloc); | |
1da177e4 LT |
1360 | } |
1361 | offset += copy; | |
1362 | length -= copy; | |
1363 | } | |
1364 | return 0; | |
1365 | error: | |
1366 | inet->cork.length -= length; | |
a11d206d | 1367 | IP6_INC_STATS(rt->rt6i_idev, IPSTATS_MIB_OUTDISCARDS); |
1da177e4 LT |
1368 | return err; |
1369 | } | |
1370 | ||
bf138862 PE |
1371 | static void ip6_cork_release(struct inet_sock *inet, struct ipv6_pinfo *np) |
1372 | { | |
1373 | inet->cork.flags &= ~IPCORK_OPT; | |
1374 | kfree(np->cork.opt); | |
1375 | np->cork.opt = NULL; | |
1376 | if (np->cork.rt) { | |
1377 | dst_release(&np->cork.rt->u.dst); | |
1378 | np->cork.rt = NULL; | |
1379 | inet->cork.flags &= ~IPCORK_ALLFRAG; | |
1380 | } | |
1381 | memset(&inet->cork.fl, 0, sizeof(inet->cork.fl)); | |
1382 | } | |
1383 | ||
1da177e4 LT |
1384 | int ip6_push_pending_frames(struct sock *sk) |
1385 | { | |
1386 | struct sk_buff *skb, *tmp_skb; | |
1387 | struct sk_buff **tail_skb; | |
1388 | struct in6_addr final_dst_buf, *final_dst = &final_dst_buf; | |
1389 | struct inet_sock *inet = inet_sk(sk); | |
1390 | struct ipv6_pinfo *np = inet6_sk(sk); | |
1391 | struct ipv6hdr *hdr; | |
1392 | struct ipv6_txoptions *opt = np->cork.opt; | |
1393 | struct rt6_info *rt = np->cork.rt; | |
1394 | struct flowi *fl = &inet->cork.fl; | |
1395 | unsigned char proto = fl->proto; | |
1396 | int err = 0; | |
1397 | ||
1398 | if ((skb = __skb_dequeue(&sk->sk_write_queue)) == NULL) | |
1399 | goto out; | |
1400 | tail_skb = &(skb_shinfo(skb)->frag_list); | |
1401 | ||
1402 | /* move skb->data to ip header from ext header */ | |
d56f90a7 | 1403 | if (skb->data < skb_network_header(skb)) |
bbe735e4 | 1404 | __skb_pull(skb, skb_network_offset(skb)); |
1da177e4 | 1405 | while ((tmp_skb = __skb_dequeue(&sk->sk_write_queue)) != NULL) { |
cfe1fc77 | 1406 | __skb_pull(tmp_skb, skb_network_header_len(skb)); |
1da177e4 LT |
1407 | *tail_skb = tmp_skb; |
1408 | tail_skb = &(tmp_skb->next); | |
1409 | skb->len += tmp_skb->len; | |
1410 | skb->data_len += tmp_skb->len; | |
1da177e4 LT |
1411 | skb->truesize += tmp_skb->truesize; |
1412 | __sock_put(tmp_skb->sk); | |
1413 | tmp_skb->destructor = NULL; | |
1414 | tmp_skb->sk = NULL; | |
1da177e4 LT |
1415 | } |
1416 | ||
1417 | ipv6_addr_copy(final_dst, &fl->fl6_dst); | |
cfe1fc77 | 1418 | __skb_pull(skb, skb_network_header_len(skb)); |
1da177e4 LT |
1419 | if (opt && opt->opt_flen) |
1420 | ipv6_push_frag_opts(skb, opt, &proto); | |
1421 | if (opt && opt->opt_nflen) | |
1422 | ipv6_push_nfrag_opts(skb, opt, &proto, &final_dst); | |
1423 | ||
e2d1bca7 ACM |
1424 | skb_push(skb, sizeof(struct ipv6hdr)); |
1425 | skb_reset_network_header(skb); | |
0660e03f | 1426 | hdr = ipv6_hdr(skb); |
1ab1457c | 1427 | |
90bcaf7b | 1428 | *(__be32*)hdr = fl->fl6_flowlabel | |
41a1f8ea | 1429 | htonl(0x60000000 | ((int)np->cork.tclass << 20)); |
1da177e4 | 1430 | |
1da177e4 LT |
1431 | hdr->hop_limit = np->cork.hop_limit; |
1432 | hdr->nexthdr = proto; | |
1433 | ipv6_addr_copy(&hdr->saddr, &fl->fl6_src); | |
1434 | ipv6_addr_copy(&hdr->daddr, final_dst); | |
1435 | ||
a2c2064f PM |
1436 | skb->priority = sk->sk_priority; |
1437 | ||
1da177e4 | 1438 | skb->dst = dst_clone(&rt->u.dst); |
a11d206d | 1439 | IP6_INC_STATS(rt->rt6i_idev, IPSTATS_MIB_OUTREQUESTS); |
14878f75 DS |
1440 | if (proto == IPPROTO_ICMPV6) { |
1441 | struct inet6_dev *idev = ip6_dst_idev(skb->dst); | |
1442 | ||
1443 | ICMP6MSGOUT_INC_STATS_BH(idev, icmp6_hdr(skb)->icmp6_type); | |
1444 | ICMP6_INC_STATS_BH(idev, ICMP6_MIB_OUTMSGS); | |
1445 | } | |
1446 | ||
ef76bc23 | 1447 | err = ip6_local_out(skb); |
1da177e4 LT |
1448 | if (err) { |
1449 | if (err > 0) | |
3320da89 | 1450 | err = np->recverr ? net_xmit_errno(err) : 0; |
1da177e4 LT |
1451 | if (err) |
1452 | goto error; | |
1453 | } | |
1454 | ||
1455 | out: | |
bf138862 | 1456 | ip6_cork_release(inet, np); |
1da177e4 LT |
1457 | return err; |
1458 | error: | |
1459 | goto out; | |
1460 | } | |
1461 | ||
1462 | void ip6_flush_pending_frames(struct sock *sk) | |
1463 | { | |
1da177e4 LT |
1464 | struct sk_buff *skb; |
1465 | ||
1466 | while ((skb = __skb_dequeue_tail(&sk->sk_write_queue)) != NULL) { | |
e1f52208 YH |
1467 | if (skb->dst) |
1468 | IP6_INC_STATS(ip6_dst_idev(skb->dst), | |
1469 | IPSTATS_MIB_OUTDISCARDS); | |
1da177e4 LT |
1470 | kfree_skb(skb); |
1471 | } | |
1472 | ||
bf138862 | 1473 | ip6_cork_release(inet_sk(sk), inet6_sk(sk)); |
1da177e4 | 1474 | } |