Commit | Line | Data |
---|---|---|
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 | ||
6e23ae2a | 82 | return nf_hook(PF_INET6, NF_INET_LOCAL_OUT, skb, NULL, skb->dst->dev, |
ef76bc23 HX |
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) | |
6e23ae2a PM |
148 | NF_HOOK(PF_INET6, NF_INET_POST_ROUTING, newskb, |
149 | NULL, newskb->dev, | |
1da177e4 LT |
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 | ||
6e23ae2a PM |
162 | return NF_HOOK(PF_INET6, NF_INET_POST_ROUTING, skb, NULL, skb->dev, |
163 | ip6_output_finish); | |
1da177e4 LT |
164 | } |
165 | ||
628a5c56 JH |
166 | static inline int ip6_skb_dst_mtu(struct sk_buff *skb) |
167 | { | |
168 | struct ipv6_pinfo *np = skb->sk ? inet6_sk(skb->sk) : NULL; | |
169 | ||
170 | return (np && np->pmtudisc == IPV6_PMTUDISC_PROBE) ? | |
171 | skb->dst->dev->mtu : dst_mtu(skb->dst); | |
172 | } | |
173 | ||
1da177e4 LT |
174 | int ip6_output(struct sk_buff *skb) |
175 | { | |
628a5c56 | 176 | if ((skb->len > ip6_skb_dst_mtu(skb) && !skb_is_gso(skb)) || |
e89e9cf5 | 177 | dst_allfrag(skb->dst)) |
1da177e4 LT |
178 | return ip6_fragment(skb, ip6_output2); |
179 | else | |
180 | return ip6_output2(skb); | |
181 | } | |
182 | ||
1da177e4 LT |
183 | /* |
184 | * xmit an sk_buff (used by TCP) | |
185 | */ | |
186 | ||
187 | int ip6_xmit(struct sock *sk, struct sk_buff *skb, struct flowi *fl, | |
188 | struct ipv6_txoptions *opt, int ipfragok) | |
189 | { | |
b30bd282 | 190 | struct ipv6_pinfo *np = inet6_sk(sk); |
1da177e4 LT |
191 | struct in6_addr *first_hop = &fl->fl6_dst; |
192 | struct dst_entry *dst = skb->dst; | |
193 | struct ipv6hdr *hdr; | |
194 | u8 proto = fl->proto; | |
195 | int seg_len = skb->len; | |
41a1f8ea | 196 | int hlimit, tclass; |
1da177e4 LT |
197 | u32 mtu; |
198 | ||
199 | if (opt) { | |
c2636b4d | 200 | unsigned int head_room; |
1da177e4 LT |
201 | |
202 | /* First: exthdrs may take lots of space (~8K for now) | |
203 | MAX_HEADER is not enough. | |
204 | */ | |
205 | head_room = opt->opt_nflen + opt->opt_flen; | |
206 | seg_len += head_room; | |
207 | head_room += sizeof(struct ipv6hdr) + LL_RESERVED_SPACE(dst->dev); | |
208 | ||
209 | if (skb_headroom(skb) < head_room) { | |
210 | struct sk_buff *skb2 = skb_realloc_headroom(skb, head_room); | |
a11d206d YH |
211 | if (skb2 == NULL) { |
212 | IP6_INC_STATS(ip6_dst_idev(skb->dst), | |
213 | IPSTATS_MIB_OUTDISCARDS); | |
214 | kfree_skb(skb); | |
1da177e4 LT |
215 | return -ENOBUFS; |
216 | } | |
a11d206d YH |
217 | kfree_skb(skb); |
218 | skb = skb2; | |
1da177e4 LT |
219 | if (sk) |
220 | skb_set_owner_w(skb, sk); | |
221 | } | |
222 | if (opt->opt_flen) | |
223 | ipv6_push_frag_opts(skb, opt, &proto); | |
224 | if (opt->opt_nflen) | |
225 | ipv6_push_nfrag_opts(skb, opt, &proto, &first_hop); | |
226 | } | |
227 | ||
e2d1bca7 ACM |
228 | skb_push(skb, sizeof(struct ipv6hdr)); |
229 | skb_reset_network_header(skb); | |
0660e03f | 230 | hdr = ipv6_hdr(skb); |
1da177e4 LT |
231 | |
232 | /* | |
233 | * Fill in the IPv6 header | |
234 | */ | |
235 | ||
1da177e4 LT |
236 | hlimit = -1; |
237 | if (np) | |
238 | hlimit = np->hop_limit; | |
239 | if (hlimit < 0) | |
240 | hlimit = dst_metric(dst, RTAX_HOPLIMIT); | |
241 | if (hlimit < 0) | |
242 | hlimit = ipv6_get_hoplimit(dst->dev); | |
243 | ||
41a1f8ea YH |
244 | tclass = -1; |
245 | if (np) | |
246 | tclass = np->tclass; | |
247 | if (tclass < 0) | |
248 | tclass = 0; | |
249 | ||
90bcaf7b | 250 | *(__be32 *)hdr = htonl(0x60000000 | (tclass << 20)) | fl->fl6_flowlabel; |
41a1f8ea | 251 | |
1da177e4 LT |
252 | hdr->payload_len = htons(seg_len); |
253 | hdr->nexthdr = proto; | |
254 | hdr->hop_limit = hlimit; | |
255 | ||
256 | ipv6_addr_copy(&hdr->saddr, &fl->fl6_src); | |
257 | ipv6_addr_copy(&hdr->daddr, first_hop); | |
258 | ||
a2c2064f | 259 | skb->priority = sk->sk_priority; |
4a19ec58 | 260 | skb->mark = sk->sk_mark; |
a2c2064f | 261 | |
1da177e4 | 262 | mtu = dst_mtu(dst); |
89114afd | 263 | if ((skb->len <= mtu) || ipfragok || skb_is_gso(skb)) { |
a11d206d YH |
264 | IP6_INC_STATS(ip6_dst_idev(skb->dst), |
265 | IPSTATS_MIB_OUTREQUESTS); | |
6e23ae2a | 266 | return NF_HOOK(PF_INET6, NF_INET_LOCAL_OUT, skb, NULL, dst->dev, |
6869c4d8 | 267 | dst_output); |
1da177e4 LT |
268 | } |
269 | ||
270 | if (net_ratelimit()) | |
271 | printk(KERN_DEBUG "IPv6: sending pkt_too_big to self\n"); | |
272 | skb->dev = dst->dev; | |
273 | icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu, skb->dev); | |
a11d206d | 274 | IP6_INC_STATS(ip6_dst_idev(skb->dst), IPSTATS_MIB_FRAGFAILS); |
1da177e4 LT |
275 | kfree_skb(skb); |
276 | return -EMSGSIZE; | |
277 | } | |
278 | ||
7159039a YH |
279 | EXPORT_SYMBOL(ip6_xmit); |
280 | ||
1da177e4 LT |
281 | /* |
282 | * To avoid extra problems ND packets are send through this | |
283 | * routine. It's code duplication but I really want to avoid | |
284 | * extra checks since ipv6_build_header is used by TCP (which | |
285 | * is for us performance critical) | |
286 | */ | |
287 | ||
288 | int ip6_nd_hdr(struct sock *sk, struct sk_buff *skb, struct net_device *dev, | |
289 | struct in6_addr *saddr, struct in6_addr *daddr, | |
290 | int proto, int len) | |
291 | { | |
292 | struct ipv6_pinfo *np = inet6_sk(sk); | |
293 | struct ipv6hdr *hdr; | |
294 | int totlen; | |
295 | ||
296 | skb->protocol = htons(ETH_P_IPV6); | |
297 | skb->dev = dev; | |
298 | ||
299 | totlen = len + sizeof(struct ipv6hdr); | |
300 | ||
55f79cc0 ACM |
301 | skb_reset_network_header(skb); |
302 | skb_put(skb, sizeof(struct ipv6hdr)); | |
0660e03f | 303 | hdr = ipv6_hdr(skb); |
1da177e4 | 304 | |
ae08e1f0 | 305 | *(__be32*)hdr = htonl(0x60000000); |
1da177e4 LT |
306 | |
307 | hdr->payload_len = htons(len); | |
308 | hdr->nexthdr = proto; | |
309 | hdr->hop_limit = np->hop_limit; | |
310 | ||
311 | ipv6_addr_copy(&hdr->saddr, saddr); | |
312 | ipv6_addr_copy(&hdr->daddr, daddr); | |
313 | ||
314 | return 0; | |
315 | } | |
316 | ||
317 | static int ip6_call_ra_chain(struct sk_buff *skb, int sel) | |
318 | { | |
319 | struct ip6_ra_chain *ra; | |
320 | struct sock *last = NULL; | |
321 | ||
322 | read_lock(&ip6_ra_lock); | |
323 | for (ra = ip6_ra_chain; ra; ra = ra->next) { | |
324 | struct sock *sk = ra->sk; | |
0bd1b59b AM |
325 | if (sk && ra->sel == sel && |
326 | (!sk->sk_bound_dev_if || | |
327 | sk->sk_bound_dev_if == skb->dev->ifindex)) { | |
1da177e4 LT |
328 | if (last) { |
329 | struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC); | |
330 | if (skb2) | |
331 | rawv6_rcv(last, skb2); | |
332 | } | |
333 | last = sk; | |
334 | } | |
335 | } | |
336 | ||
337 | if (last) { | |
338 | rawv6_rcv(last, skb); | |
339 | read_unlock(&ip6_ra_lock); | |
340 | return 1; | |
341 | } | |
342 | read_unlock(&ip6_ra_lock); | |
343 | return 0; | |
344 | } | |
345 | ||
e21e0b5f VN |
346 | static int ip6_forward_proxy_check(struct sk_buff *skb) |
347 | { | |
0660e03f | 348 | struct ipv6hdr *hdr = ipv6_hdr(skb); |
e21e0b5f VN |
349 | u8 nexthdr = hdr->nexthdr; |
350 | int offset; | |
351 | ||
352 | if (ipv6_ext_hdr(nexthdr)) { | |
353 | offset = ipv6_skip_exthdr(skb, sizeof(*hdr), &nexthdr); | |
354 | if (offset < 0) | |
355 | return 0; | |
356 | } else | |
357 | offset = sizeof(struct ipv6hdr); | |
358 | ||
359 | if (nexthdr == IPPROTO_ICMPV6) { | |
360 | struct icmp6hdr *icmp6; | |
361 | ||
d56f90a7 ACM |
362 | if (!pskb_may_pull(skb, (skb_network_header(skb) + |
363 | offset + 1 - skb->data))) | |
e21e0b5f VN |
364 | return 0; |
365 | ||
d56f90a7 | 366 | icmp6 = (struct icmp6hdr *)(skb_network_header(skb) + offset); |
e21e0b5f VN |
367 | |
368 | switch (icmp6->icmp6_type) { | |
369 | case NDISC_ROUTER_SOLICITATION: | |
370 | case NDISC_ROUTER_ADVERTISEMENT: | |
371 | case NDISC_NEIGHBOUR_SOLICITATION: | |
372 | case NDISC_NEIGHBOUR_ADVERTISEMENT: | |
373 | case NDISC_REDIRECT: | |
374 | /* For reaction involving unicast neighbor discovery | |
375 | * message destined to the proxied address, pass it to | |
376 | * input function. | |
377 | */ | |
378 | return 1; | |
379 | default: | |
380 | break; | |
381 | } | |
382 | } | |
383 | ||
74553b09 VN |
384 | /* |
385 | * The proxying router can't forward traffic sent to a link-local | |
386 | * address, so signal the sender and discard the packet. This | |
387 | * behavior is clarified by the MIPv6 specification. | |
388 | */ | |
389 | if (ipv6_addr_type(&hdr->daddr) & IPV6_ADDR_LINKLOCAL) { | |
390 | dst_link_failure(skb); | |
391 | return -1; | |
392 | } | |
393 | ||
e21e0b5f VN |
394 | return 0; |
395 | } | |
396 | ||
1da177e4 LT |
397 | static inline int ip6_forward_finish(struct sk_buff *skb) |
398 | { | |
399 | return dst_output(skb); | |
400 | } | |
401 | ||
402 | int ip6_forward(struct sk_buff *skb) | |
403 | { | |
404 | struct dst_entry *dst = skb->dst; | |
0660e03f | 405 | struct ipv6hdr *hdr = ipv6_hdr(skb); |
1da177e4 | 406 | struct inet6_skb_parm *opt = IP6CB(skb); |
1ab1457c | 407 | |
1da177e4 LT |
408 | if (ipv6_devconf.forwarding == 0) |
409 | goto error; | |
410 | ||
411 | if (!xfrm6_policy_check(NULL, XFRM_POLICY_FWD, skb)) { | |
a11d206d | 412 | IP6_INC_STATS(ip6_dst_idev(dst), IPSTATS_MIB_INDISCARDS); |
1da177e4 LT |
413 | goto drop; |
414 | } | |
415 | ||
35fc92a9 | 416 | skb_forward_csum(skb); |
1da177e4 LT |
417 | |
418 | /* | |
419 | * We DO NOT make any processing on | |
420 | * RA packets, pushing them to user level AS IS | |
421 | * without ane WARRANTY that application will be able | |
422 | * to interpret them. The reason is that we | |
423 | * cannot make anything clever here. | |
424 | * | |
425 | * We are not end-node, so that if packet contains | |
426 | * AH/ESP, we cannot make anything. | |
427 | * Defragmentation also would be mistake, RA packets | |
428 | * cannot be fragmented, because there is no warranty | |
429 | * that different fragments will go along one path. --ANK | |
430 | */ | |
431 | if (opt->ra) { | |
d56f90a7 | 432 | u8 *ptr = skb_network_header(skb) + opt->ra; |
1da177e4 LT |
433 | if (ip6_call_ra_chain(skb, (ptr[2]<<8) + ptr[3])) |
434 | return 0; | |
435 | } | |
436 | ||
437 | /* | |
438 | * check and decrement ttl | |
439 | */ | |
440 | if (hdr->hop_limit <= 1) { | |
441 | /* Force OUTPUT device used as source address */ | |
442 | skb->dev = dst->dev; | |
443 | icmpv6_send(skb, ICMPV6_TIME_EXCEED, ICMPV6_EXC_HOPLIMIT, | |
444 | 0, skb->dev); | |
a11d206d | 445 | IP6_INC_STATS_BH(ip6_dst_idev(dst), IPSTATS_MIB_INHDRERRORS); |
1da177e4 LT |
446 | |
447 | kfree_skb(skb); | |
448 | return -ETIMEDOUT; | |
449 | } | |
450 | ||
fbea49e1 YH |
451 | /* XXX: idev->cnf.proxy_ndp? */ |
452 | if (ipv6_devconf.proxy_ndp && | |
426b5303 | 453 | pneigh_lookup(&nd_tbl, &init_net, &hdr->daddr, skb->dev, 0)) { |
74553b09 VN |
454 | int proxied = ip6_forward_proxy_check(skb); |
455 | if (proxied > 0) | |
e21e0b5f | 456 | return ip6_input(skb); |
74553b09 | 457 | else if (proxied < 0) { |
a11d206d | 458 | IP6_INC_STATS(ip6_dst_idev(dst), IPSTATS_MIB_INDISCARDS); |
74553b09 VN |
459 | goto drop; |
460 | } | |
e21e0b5f VN |
461 | } |
462 | ||
1da177e4 | 463 | if (!xfrm6_route_forward(skb)) { |
a11d206d | 464 | IP6_INC_STATS(ip6_dst_idev(dst), IPSTATS_MIB_INDISCARDS); |
1da177e4 LT |
465 | goto drop; |
466 | } | |
467 | dst = skb->dst; | |
468 | ||
469 | /* IPv6 specs say nothing about it, but it is clear that we cannot | |
470 | send redirects to source routed frames. | |
1e5dc146 | 471 | We don't send redirects to frames decapsulated from IPsec. |
1da177e4 | 472 | */ |
1e5dc146 MN |
473 | if (skb->dev == dst->dev && dst->neighbour && opt->srcrt == 0 && |
474 | !skb->sp) { | |
1da177e4 LT |
475 | struct in6_addr *target = NULL; |
476 | struct rt6_info *rt; | |
477 | struct neighbour *n = dst->neighbour; | |
478 | ||
479 | /* | |
480 | * incoming and outgoing devices are the same | |
481 | * send a redirect. | |
482 | */ | |
483 | ||
484 | rt = (struct rt6_info *) dst; | |
485 | if ((rt->rt6i_flags & RTF_GATEWAY)) | |
486 | target = (struct in6_addr*)&n->primary_key; | |
487 | else | |
488 | target = &hdr->daddr; | |
489 | ||
490 | /* Limit redirects both by destination (here) | |
491 | and by source (inside ndisc_send_redirect) | |
492 | */ | |
493 | if (xrlim_allow(dst, 1*HZ)) | |
494 | ndisc_send_redirect(skb, n, target); | |
5bb1ab09 DS |
495 | } else { |
496 | int addrtype = ipv6_addr_type(&hdr->saddr); | |
497 | ||
1da177e4 | 498 | /* This check is security critical. */ |
5bb1ab09 DS |
499 | if (addrtype & (IPV6_ADDR_MULTICAST|IPV6_ADDR_LOOPBACK)) |
500 | goto error; | |
501 | if (addrtype & IPV6_ADDR_LINKLOCAL) { | |
502 | icmpv6_send(skb, ICMPV6_DEST_UNREACH, | |
503 | ICMPV6_NOT_NEIGHBOUR, 0, skb->dev); | |
504 | goto error; | |
505 | } | |
1da177e4 LT |
506 | } |
507 | ||
508 | if (skb->len > dst_mtu(dst)) { | |
509 | /* Again, force OUTPUT device used as source address */ | |
510 | skb->dev = dst->dev; | |
511 | icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, dst_mtu(dst), skb->dev); | |
a11d206d YH |
512 | IP6_INC_STATS_BH(ip6_dst_idev(dst), IPSTATS_MIB_INTOOBIGERRORS); |
513 | IP6_INC_STATS_BH(ip6_dst_idev(dst), IPSTATS_MIB_FRAGFAILS); | |
1da177e4 LT |
514 | kfree_skb(skb); |
515 | return -EMSGSIZE; | |
516 | } | |
517 | ||
518 | if (skb_cow(skb, dst->dev->hard_header_len)) { | |
a11d206d | 519 | IP6_INC_STATS(ip6_dst_idev(dst), IPSTATS_MIB_OUTDISCARDS); |
1da177e4 LT |
520 | goto drop; |
521 | } | |
522 | ||
0660e03f | 523 | hdr = ipv6_hdr(skb); |
1da177e4 LT |
524 | |
525 | /* Mangling hops number delayed to point after skb COW */ | |
1ab1457c | 526 | |
1da177e4 LT |
527 | hdr->hop_limit--; |
528 | ||
a11d206d | 529 | IP6_INC_STATS_BH(ip6_dst_idev(dst), IPSTATS_MIB_OUTFORWDATAGRAMS); |
6e23ae2a PM |
530 | return NF_HOOK(PF_INET6, NF_INET_FORWARD, skb, skb->dev, dst->dev, |
531 | ip6_forward_finish); | |
1da177e4 LT |
532 | |
533 | error: | |
a11d206d | 534 | IP6_INC_STATS_BH(ip6_dst_idev(dst), IPSTATS_MIB_INADDRERRORS); |
1da177e4 LT |
535 | drop: |
536 | kfree_skb(skb); | |
537 | return -EINVAL; | |
538 | } | |
539 | ||
540 | static void ip6_copy_metadata(struct sk_buff *to, struct sk_buff *from) | |
541 | { | |
542 | to->pkt_type = from->pkt_type; | |
543 | to->priority = from->priority; | |
544 | to->protocol = from->protocol; | |
1da177e4 LT |
545 | dst_release(to->dst); |
546 | to->dst = dst_clone(from->dst); | |
547 | to->dev = from->dev; | |
82e91ffe | 548 | to->mark = from->mark; |
1da177e4 LT |
549 | |
550 | #ifdef CONFIG_NET_SCHED | |
551 | to->tc_index = from->tc_index; | |
552 | #endif | |
e7ac05f3 | 553 | nf_copy(to, from); |
ba9dda3a JK |
554 | #if defined(CONFIG_NETFILTER_XT_TARGET_TRACE) || \ |
555 | defined(CONFIG_NETFILTER_XT_TARGET_TRACE_MODULE) | |
556 | to->nf_trace = from->nf_trace; | |
557 | #endif | |
984bc16c | 558 | skb_copy_secmark(to, from); |
1da177e4 LT |
559 | } |
560 | ||
561 | int ip6_find_1stfragopt(struct sk_buff *skb, u8 **nexthdr) | |
562 | { | |
563 | u16 offset = sizeof(struct ipv6hdr); | |
0660e03f ACM |
564 | struct ipv6_opt_hdr *exthdr = |
565 | (struct ipv6_opt_hdr *)(ipv6_hdr(skb) + 1); | |
27a884dc | 566 | unsigned int packet_len = skb->tail - skb->network_header; |
1da177e4 | 567 | int found_rhdr = 0; |
0660e03f | 568 | *nexthdr = &ipv6_hdr(skb)->nexthdr; |
1da177e4 LT |
569 | |
570 | while (offset + 1 <= packet_len) { | |
571 | ||
572 | switch (**nexthdr) { | |
573 | ||
574 | case NEXTHDR_HOP: | |
27637df9 | 575 | break; |
1da177e4 | 576 | case NEXTHDR_ROUTING: |
27637df9 MN |
577 | found_rhdr = 1; |
578 | break; | |
1da177e4 | 579 | case NEXTHDR_DEST: |
59fbb3a6 | 580 | #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE) |
27637df9 MN |
581 | if (ipv6_find_tlv(skb, offset, IPV6_TLV_HAO) >= 0) |
582 | break; | |
583 | #endif | |
584 | if (found_rhdr) | |
585 | return offset; | |
1da177e4 LT |
586 | break; |
587 | default : | |
588 | return offset; | |
589 | } | |
27637df9 MN |
590 | |
591 | offset += ipv6_optlen(exthdr); | |
592 | *nexthdr = &exthdr->nexthdr; | |
d56f90a7 ACM |
593 | exthdr = (struct ipv6_opt_hdr *)(skb_network_header(skb) + |
594 | offset); | |
1da177e4 LT |
595 | } |
596 | ||
597 | return offset; | |
598 | } | |
599 | ||
600 | static int ip6_fragment(struct sk_buff *skb, int (*output)(struct sk_buff *)) | |
601 | { | |
602 | struct net_device *dev; | |
603 | struct sk_buff *frag; | |
604 | struct rt6_info *rt = (struct rt6_info*)skb->dst; | |
d91675f9 | 605 | struct ipv6_pinfo *np = skb->sk ? inet6_sk(skb->sk) : NULL; |
1da177e4 LT |
606 | struct ipv6hdr *tmp_hdr; |
607 | struct frag_hdr *fh; | |
608 | unsigned int mtu, hlen, left, len; | |
ae08e1f0 | 609 | __be32 frag_id = 0; |
1da177e4 LT |
610 | int ptr, offset = 0, err=0; |
611 | u8 *prevhdr, nexthdr = 0; | |
612 | ||
613 | dev = rt->u.dst.dev; | |
614 | hlen = ip6_find_1stfragopt(skb, &prevhdr); | |
615 | nexthdr = *prevhdr; | |
616 | ||
628a5c56 | 617 | mtu = ip6_skb_dst_mtu(skb); |
b881ef76 JH |
618 | |
619 | /* We must not fragment if the socket is set to force MTU discovery | |
620 | * or if the skb it not generated by a local socket. (This last | |
621 | * check should be redundant, but it's free.) | |
622 | */ | |
b5c15fc0 | 623 | if (!skb->local_df) { |
b881ef76 JH |
624 | skb->dev = skb->dst->dev; |
625 | icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu, skb->dev); | |
626 | IP6_INC_STATS(ip6_dst_idev(skb->dst), IPSTATS_MIB_FRAGFAILS); | |
627 | kfree_skb(skb); | |
628 | return -EMSGSIZE; | |
629 | } | |
630 | ||
d91675f9 YH |
631 | if (np && np->frag_size < mtu) { |
632 | if (np->frag_size) | |
633 | mtu = np->frag_size; | |
634 | } | |
635 | mtu -= hlen + sizeof(struct frag_hdr); | |
1da177e4 LT |
636 | |
637 | if (skb_shinfo(skb)->frag_list) { | |
638 | int first_len = skb_pagelen(skb); | |
29ffe1a5 | 639 | int truesizes = 0; |
1da177e4 LT |
640 | |
641 | if (first_len - hlen > mtu || | |
642 | ((first_len - hlen) & 7) || | |
643 | skb_cloned(skb)) | |
644 | goto slow_path; | |
645 | ||
646 | for (frag = skb_shinfo(skb)->frag_list; frag; frag = frag->next) { | |
647 | /* Correct geometry. */ | |
648 | if (frag->len > mtu || | |
649 | ((frag->len & 7) && frag->next) || | |
650 | skb_headroom(frag) < hlen) | |
651 | goto slow_path; | |
652 | ||
1da177e4 LT |
653 | /* Partially cloned skb? */ |
654 | if (skb_shared(frag)) | |
655 | goto slow_path; | |
2fdba6b0 HX |
656 | |
657 | BUG_ON(frag->sk); | |
658 | if (skb->sk) { | |
659 | sock_hold(skb->sk); | |
660 | frag->sk = skb->sk; | |
661 | frag->destructor = sock_wfree; | |
29ffe1a5 | 662 | truesizes += frag->truesize; |
2fdba6b0 | 663 | } |
1da177e4 LT |
664 | } |
665 | ||
666 | err = 0; | |
667 | offset = 0; | |
668 | frag = skb_shinfo(skb)->frag_list; | |
669 | skb_shinfo(skb)->frag_list = NULL; | |
670 | /* BUILD HEADER */ | |
671 | ||
9a217a1c | 672 | *prevhdr = NEXTHDR_FRAGMENT; |
d56f90a7 | 673 | tmp_hdr = kmemdup(skb_network_header(skb), hlen, GFP_ATOMIC); |
1da177e4 | 674 | if (!tmp_hdr) { |
a11d206d | 675 | IP6_INC_STATS(ip6_dst_idev(skb->dst), IPSTATS_MIB_FRAGFAILS); |
1da177e4 LT |
676 | return -ENOMEM; |
677 | } | |
678 | ||
1da177e4 LT |
679 | __skb_pull(skb, hlen); |
680 | fh = (struct frag_hdr*)__skb_push(skb, sizeof(struct frag_hdr)); | |
e2d1bca7 ACM |
681 | __skb_push(skb, hlen); |
682 | skb_reset_network_header(skb); | |
d56f90a7 | 683 | memcpy(skb_network_header(skb), tmp_hdr, hlen); |
1da177e4 LT |
684 | |
685 | ipv6_select_ident(skb, fh); | |
686 | fh->nexthdr = nexthdr; | |
687 | fh->reserved = 0; | |
688 | fh->frag_off = htons(IP6_MF); | |
689 | frag_id = fh->identification; | |
690 | ||
691 | first_len = skb_pagelen(skb); | |
692 | skb->data_len = first_len - skb_headlen(skb); | |
29ffe1a5 | 693 | skb->truesize -= truesizes; |
1da177e4 | 694 | skb->len = first_len; |
0660e03f ACM |
695 | ipv6_hdr(skb)->payload_len = htons(first_len - |
696 | sizeof(struct ipv6hdr)); | |
a11d206d YH |
697 | |
698 | dst_hold(&rt->u.dst); | |
1da177e4 LT |
699 | |
700 | for (;;) { | |
701 | /* Prepare header of the next frame, | |
702 | * before previous one went down. */ | |
703 | if (frag) { | |
704 | frag->ip_summed = CHECKSUM_NONE; | |
badff6d0 | 705 | skb_reset_transport_header(frag); |
1da177e4 | 706 | fh = (struct frag_hdr*)__skb_push(frag, sizeof(struct frag_hdr)); |
e2d1bca7 ACM |
707 | __skb_push(frag, hlen); |
708 | skb_reset_network_header(frag); | |
d56f90a7 ACM |
709 | memcpy(skb_network_header(frag), tmp_hdr, |
710 | hlen); | |
1da177e4 LT |
711 | offset += skb->len - hlen - sizeof(struct frag_hdr); |
712 | fh->nexthdr = nexthdr; | |
713 | fh->reserved = 0; | |
714 | fh->frag_off = htons(offset); | |
715 | if (frag->next != NULL) | |
716 | fh->frag_off |= htons(IP6_MF); | |
717 | fh->identification = frag_id; | |
0660e03f ACM |
718 | ipv6_hdr(frag)->payload_len = |
719 | htons(frag->len - | |
720 | sizeof(struct ipv6hdr)); | |
1da177e4 LT |
721 | ip6_copy_metadata(frag, skb); |
722 | } | |
1ab1457c | 723 | |
1da177e4 | 724 | err = output(skb); |
dafee490 | 725 | if(!err) |
a11d206d | 726 | IP6_INC_STATS(ip6_dst_idev(&rt->u.dst), IPSTATS_MIB_FRAGCREATES); |
dafee490 | 727 | |
1da177e4 LT |
728 | if (err || !frag) |
729 | break; | |
730 | ||
731 | skb = frag; | |
732 | frag = skb->next; | |
733 | skb->next = NULL; | |
734 | } | |
735 | ||
a51482bd | 736 | kfree(tmp_hdr); |
1da177e4 LT |
737 | |
738 | if (err == 0) { | |
a11d206d YH |
739 | IP6_INC_STATS(ip6_dst_idev(&rt->u.dst), IPSTATS_MIB_FRAGOKS); |
740 | dst_release(&rt->u.dst); | |
1da177e4 LT |
741 | return 0; |
742 | } | |
743 | ||
744 | while (frag) { | |
745 | skb = frag->next; | |
746 | kfree_skb(frag); | |
747 | frag = skb; | |
748 | } | |
749 | ||
a11d206d YH |
750 | IP6_INC_STATS(ip6_dst_idev(&rt->u.dst), IPSTATS_MIB_FRAGFAILS); |
751 | dst_release(&rt->u.dst); | |
1da177e4 LT |
752 | return err; |
753 | } | |
754 | ||
755 | slow_path: | |
756 | left = skb->len - hlen; /* Space per frame */ | |
757 | ptr = hlen; /* Where to start from */ | |
758 | ||
759 | /* | |
760 | * Fragment the datagram. | |
761 | */ | |
762 | ||
763 | *prevhdr = NEXTHDR_FRAGMENT; | |
764 | ||
765 | /* | |
766 | * Keep copying data until we run out. | |
767 | */ | |
768 | while(left > 0) { | |
769 | len = left; | |
770 | /* IF: it doesn't fit, use 'mtu' - the data space left */ | |
771 | if (len > mtu) | |
772 | len = mtu; | |
773 | /* IF: we are not sending upto and including the packet end | |
774 | then align the next start on an eight byte boundary */ | |
775 | if (len < left) { | |
776 | len &= ~7; | |
777 | } | |
778 | /* | |
779 | * Allocate buffer. | |
780 | */ | |
781 | ||
782 | if ((frag = alloc_skb(len+hlen+sizeof(struct frag_hdr)+LL_RESERVED_SPACE(rt->u.dst.dev), GFP_ATOMIC)) == NULL) { | |
64ce2073 | 783 | NETDEBUG(KERN_INFO "IPv6: frag: no memory for new fragment!\n"); |
a11d206d YH |
784 | IP6_INC_STATS(ip6_dst_idev(skb->dst), |
785 | IPSTATS_MIB_FRAGFAILS); | |
1da177e4 LT |
786 | err = -ENOMEM; |
787 | goto fail; | |
788 | } | |
789 | ||
790 | /* | |
791 | * Set up data on packet | |
792 | */ | |
793 | ||
794 | ip6_copy_metadata(frag, skb); | |
795 | skb_reserve(frag, LL_RESERVED_SPACE(rt->u.dst.dev)); | |
796 | skb_put(frag, len + hlen + sizeof(struct frag_hdr)); | |
c1d2bbe1 | 797 | skb_reset_network_header(frag); |
badff6d0 | 798 | fh = (struct frag_hdr *)(skb_network_header(frag) + hlen); |
b0e380b1 ACM |
799 | frag->transport_header = (frag->network_header + hlen + |
800 | sizeof(struct frag_hdr)); | |
1da177e4 LT |
801 | |
802 | /* | |
803 | * Charge the memory for the fragment to any owner | |
804 | * it might possess | |
805 | */ | |
806 | if (skb->sk) | |
807 | skb_set_owner_w(frag, skb->sk); | |
808 | ||
809 | /* | |
810 | * Copy the packet header into the new buffer. | |
811 | */ | |
d626f62b | 812 | skb_copy_from_linear_data(skb, skb_network_header(frag), hlen); |
1da177e4 LT |
813 | |
814 | /* | |
815 | * Build fragment header. | |
816 | */ | |
817 | fh->nexthdr = nexthdr; | |
818 | fh->reserved = 0; | |
f36d6ab1 | 819 | if (!frag_id) { |
1da177e4 LT |
820 | ipv6_select_ident(skb, fh); |
821 | frag_id = fh->identification; | |
822 | } else | |
823 | fh->identification = frag_id; | |
824 | ||
825 | /* | |
826 | * Copy a block of the IP datagram. | |
827 | */ | |
8984e41d | 828 | if (skb_copy_bits(skb, ptr, skb_transport_header(frag), len)) |
1da177e4 LT |
829 | BUG(); |
830 | left -= len; | |
831 | ||
832 | fh->frag_off = htons(offset); | |
833 | if (left > 0) | |
834 | fh->frag_off |= htons(IP6_MF); | |
0660e03f ACM |
835 | ipv6_hdr(frag)->payload_len = htons(frag->len - |
836 | sizeof(struct ipv6hdr)); | |
1da177e4 LT |
837 | |
838 | ptr += len; | |
839 | offset += len; | |
840 | ||
841 | /* | |
842 | * Put this fragment into the sending queue. | |
843 | */ | |
1da177e4 LT |
844 | err = output(frag); |
845 | if (err) | |
846 | goto fail; | |
dafee490 | 847 | |
a11d206d | 848 | IP6_INC_STATS(ip6_dst_idev(skb->dst), IPSTATS_MIB_FRAGCREATES); |
1da177e4 | 849 | } |
a11d206d YH |
850 | IP6_INC_STATS(ip6_dst_idev(skb->dst), |
851 | IPSTATS_MIB_FRAGOKS); | |
1da177e4 | 852 | kfree_skb(skb); |
1da177e4 LT |
853 | return err; |
854 | ||
855 | fail: | |
a11d206d YH |
856 | IP6_INC_STATS(ip6_dst_idev(skb->dst), |
857 | IPSTATS_MIB_FRAGFAILS); | |
1ab1457c | 858 | kfree_skb(skb); |
1da177e4 LT |
859 | return err; |
860 | } | |
861 | ||
cf6b1982 YH |
862 | static inline int ip6_rt_check(struct rt6key *rt_key, |
863 | struct in6_addr *fl_addr, | |
864 | struct in6_addr *addr_cache) | |
865 | { | |
866 | return ((rt_key->plen != 128 || !ipv6_addr_equal(fl_addr, &rt_key->addr)) && | |
867 | (addr_cache == NULL || !ipv6_addr_equal(fl_addr, addr_cache))); | |
868 | } | |
869 | ||
497c615a HX |
870 | static struct dst_entry *ip6_sk_dst_check(struct sock *sk, |
871 | struct dst_entry *dst, | |
872 | struct flowi *fl) | |
1da177e4 | 873 | { |
497c615a HX |
874 | struct ipv6_pinfo *np = inet6_sk(sk); |
875 | struct rt6_info *rt = (struct rt6_info *)dst; | |
1da177e4 | 876 | |
497c615a HX |
877 | if (!dst) |
878 | goto out; | |
879 | ||
880 | /* Yes, checking route validity in not connected | |
881 | * case is not very simple. Take into account, | |
882 | * that we do not support routing by source, TOS, | |
883 | * and MSG_DONTROUTE --ANK (980726) | |
884 | * | |
cf6b1982 YH |
885 | * 1. ip6_rt_check(): If route was host route, |
886 | * check that cached destination is current. | |
497c615a HX |
887 | * If it is network route, we still may |
888 | * check its validity using saved pointer | |
889 | * to the last used address: daddr_cache. | |
890 | * We do not want to save whole address now, | |
891 | * (because main consumer of this service | |
892 | * is tcp, which has not this problem), | |
893 | * so that the last trick works only on connected | |
894 | * sockets. | |
895 | * 2. oif also should be the same. | |
896 | */ | |
cf6b1982 | 897 | if (ip6_rt_check(&rt->rt6i_dst, &fl->fl6_dst, np->daddr_cache) || |
8e1ef0a9 YH |
898 | #ifdef CONFIG_IPV6_SUBTREES |
899 | ip6_rt_check(&rt->rt6i_src, &fl->fl6_src, np->saddr_cache) || | |
900 | #endif | |
cf6b1982 | 901 | (fl->oif && fl->oif != dst->dev->ifindex)) { |
497c615a HX |
902 | dst_release(dst); |
903 | dst = NULL; | |
1da177e4 LT |
904 | } |
905 | ||
497c615a HX |
906 | out: |
907 | return dst; | |
908 | } | |
909 | ||
910 | static int ip6_dst_lookup_tail(struct sock *sk, | |
911 | struct dst_entry **dst, struct flowi *fl) | |
912 | { | |
913 | int err; | |
914 | ||
1da177e4 | 915 | if (*dst == NULL) |
c20121ae | 916 | *dst = ip6_route_output(sk->sk_net, sk, fl); |
1da177e4 LT |
917 | |
918 | if ((err = (*dst)->error)) | |
919 | goto out_err_release; | |
920 | ||
921 | if (ipv6_addr_any(&fl->fl6_src)) { | |
5e5f3f0f YH |
922 | err = ipv6_dev_get_saddr(ip6_dst_idev(*dst)->dev, |
923 | &fl->fl6_dst, &fl->fl6_src); | |
44456d37 | 924 | if (err) |
1da177e4 | 925 | goto out_err_release; |
1da177e4 LT |
926 | } |
927 | ||
95c385b4 NH |
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 | if (!((*dst)->neighbour->nud_state & NUD_VALID)) { | |
938 | struct inet6_ifaddr *ifp; | |
939 | struct flowi fl_gw; | |
940 | int redirect; | |
941 | ||
1cab3da6 DL |
942 | ifp = ipv6_get_ifaddr(&init_net, &fl->fl6_src, |
943 | (*dst)->dev, 1); | |
95c385b4 NH |
944 | |
945 | redirect = (ifp && ifp->flags & IFA_F_OPTIMISTIC); | |
946 | if (ifp) | |
947 | in6_ifa_put(ifp); | |
948 | ||
949 | if (redirect) { | |
950 | /* | |
951 | * We need to get the dst entry for the | |
952 | * default router instead | |
953 | */ | |
954 | dst_release(*dst); | |
955 | memcpy(&fl_gw, fl, sizeof(struct flowi)); | |
956 | memset(&fl_gw.fl6_dst, 0, sizeof(struct in6_addr)); | |
c20121ae | 957 | *dst = ip6_route_output(sk->sk_net, sk, &fl_gw); |
95c385b4 NH |
958 | if ((err = (*dst)->error)) |
959 | goto out_err_release; | |
960 | } | |
961 | } | |
962 | #endif | |
963 | ||
1da177e4 LT |
964 | return 0; |
965 | ||
966 | out_err_release: | |
ca46f9c8 MC |
967 | if (err == -ENETUNREACH) |
968 | IP6_INC_STATS_BH(NULL, IPSTATS_MIB_OUTNOROUTES); | |
1da177e4 LT |
969 | dst_release(*dst); |
970 | *dst = NULL; | |
971 | return err; | |
972 | } | |
34a0b3cd | 973 | |
497c615a HX |
974 | /** |
975 | * ip6_dst_lookup - perform route lookup on flow | |
976 | * @sk: socket which provides route info | |
977 | * @dst: pointer to dst_entry * for result | |
978 | * @fl: flow to lookup | |
979 | * | |
980 | * This function performs a route lookup on the given flow. | |
981 | * | |
982 | * It returns zero on success, or a standard errno code on error. | |
983 | */ | |
984 | int ip6_dst_lookup(struct sock *sk, struct dst_entry **dst, struct flowi *fl) | |
985 | { | |
986 | *dst = NULL; | |
987 | return ip6_dst_lookup_tail(sk, dst, fl); | |
988 | } | |
3cf3dc6c ACM |
989 | EXPORT_SYMBOL_GPL(ip6_dst_lookup); |
990 | ||
497c615a HX |
991 | /** |
992 | * ip6_sk_dst_lookup - perform socket cached route lookup on flow | |
993 | * @sk: socket which provides the dst cache and route info | |
994 | * @dst: pointer to dst_entry * for result | |
995 | * @fl: flow to lookup | |
996 | * | |
997 | * This function performs a route lookup on the given flow with the | |
998 | * possibility of using the cached route in the socket if it is valid. | |
999 | * It will take the socket dst lock when operating on the dst cache. | |
1000 | * As a result, this function can only be used in process context. | |
1001 | * | |
1002 | * It returns zero on success, or a standard errno code on error. | |
1003 | */ | |
1004 | int ip6_sk_dst_lookup(struct sock *sk, struct dst_entry **dst, struct flowi *fl) | |
1005 | { | |
1006 | *dst = NULL; | |
1007 | if (sk) { | |
1008 | *dst = sk_dst_check(sk, inet6_sk(sk)->dst_cookie); | |
1009 | *dst = ip6_sk_dst_check(sk, *dst, fl); | |
1010 | } | |
1011 | ||
1012 | return ip6_dst_lookup_tail(sk, dst, fl); | |
1013 | } | |
1014 | EXPORT_SYMBOL_GPL(ip6_sk_dst_lookup); | |
1015 | ||
34a0b3cd | 1016 | static inline int ip6_ufo_append_data(struct sock *sk, |
e89e9cf5 AR |
1017 | int getfrag(void *from, char *to, int offset, int len, |
1018 | int odd, struct sk_buff *skb), | |
1019 | void *from, int length, int hh_len, int fragheaderlen, | |
1020 | int transhdrlen, int mtu,unsigned int flags) | |
1021 | ||
1022 | { | |
1023 | struct sk_buff *skb; | |
1024 | int err; | |
1025 | ||
1026 | /* There is support for UDP large send offload by network | |
1027 | * device, so create one single skb packet containing complete | |
1028 | * udp datagram | |
1029 | */ | |
1030 | if ((skb = skb_peek_tail(&sk->sk_write_queue)) == NULL) { | |
1031 | skb = sock_alloc_send_skb(sk, | |
1032 | hh_len + fragheaderlen + transhdrlen + 20, | |
1033 | (flags & MSG_DONTWAIT), &err); | |
1034 | if (skb == NULL) | |
1035 | return -ENOMEM; | |
1036 | ||
1037 | /* reserve space for Hardware header */ | |
1038 | skb_reserve(skb, hh_len); | |
1039 | ||
1040 | /* create space for UDP/IP header */ | |
1041 | skb_put(skb,fragheaderlen + transhdrlen); | |
1042 | ||
1043 | /* initialize network header pointer */ | |
c1d2bbe1 | 1044 | skb_reset_network_header(skb); |
e89e9cf5 AR |
1045 | |
1046 | /* initialize protocol header pointer */ | |
b0e380b1 | 1047 | skb->transport_header = skb->network_header + fragheaderlen; |
e89e9cf5 | 1048 | |
84fa7933 | 1049 | skb->ip_summed = CHECKSUM_PARTIAL; |
e89e9cf5 AR |
1050 | skb->csum = 0; |
1051 | sk->sk_sndmsg_off = 0; | |
1052 | } | |
1053 | ||
1054 | err = skb_append_datato_frags(sk,skb, getfrag, from, | |
1055 | (length - transhdrlen)); | |
1056 | if (!err) { | |
1057 | struct frag_hdr fhdr; | |
1058 | ||
1059 | /* specify the length of each IP datagram fragment*/ | |
1ab1457c | 1060 | skb_shinfo(skb)->gso_size = mtu - fragheaderlen - |
7967168c | 1061 | sizeof(struct frag_hdr); |
f83ef8c0 | 1062 | skb_shinfo(skb)->gso_type = SKB_GSO_UDP; |
e89e9cf5 AR |
1063 | ipv6_select_ident(skb, &fhdr); |
1064 | skb_shinfo(skb)->ip6_frag_id = fhdr.identification; | |
1065 | __skb_queue_tail(&sk->sk_write_queue, skb); | |
1066 | ||
1067 | return 0; | |
1068 | } | |
1069 | /* There is not enough support do UPD LSO, | |
1070 | * so follow normal path | |
1071 | */ | |
1072 | kfree_skb(skb); | |
1073 | ||
1074 | return err; | |
1075 | } | |
1da177e4 | 1076 | |
41a1f8ea YH |
1077 | int ip6_append_data(struct sock *sk, int getfrag(void *from, char *to, |
1078 | int offset, int len, int odd, struct sk_buff *skb), | |
1079 | void *from, int length, int transhdrlen, | |
1080 | int hlimit, int tclass, struct ipv6_txoptions *opt, struct flowi *fl, | |
1081 | struct rt6_info *rt, unsigned int flags) | |
1da177e4 LT |
1082 | { |
1083 | struct inet_sock *inet = inet_sk(sk); | |
1084 | struct ipv6_pinfo *np = inet6_sk(sk); | |
1085 | struct sk_buff *skb; | |
1086 | unsigned int maxfraglen, fragheaderlen; | |
1087 | int exthdrlen; | |
1088 | int hh_len; | |
1089 | int mtu; | |
1090 | int copy; | |
1091 | int err; | |
1092 | int offset = 0; | |
1093 | int csummode = CHECKSUM_NONE; | |
1094 | ||
1095 | if (flags&MSG_PROBE) | |
1096 | return 0; | |
1097 | if (skb_queue_empty(&sk->sk_write_queue)) { | |
1098 | /* | |
1099 | * setup for corking | |
1100 | */ | |
1101 | if (opt) { | |
1102 | if (np->cork.opt == NULL) { | |
1103 | np->cork.opt = kmalloc(opt->tot_len, | |
1104 | sk->sk_allocation); | |
1105 | if (unlikely(np->cork.opt == NULL)) | |
1106 | return -ENOBUFS; | |
1107 | } else if (np->cork.opt->tot_len < opt->tot_len) { | |
1108 | printk(KERN_DEBUG "ip6_append_data: invalid option length\n"); | |
1109 | return -EINVAL; | |
1110 | } | |
1111 | memcpy(np->cork.opt, opt, opt->tot_len); | |
1112 | inet->cork.flags |= IPCORK_OPT; | |
1113 | /* need source address above miyazawa*/ | |
1114 | } | |
1115 | dst_hold(&rt->u.dst); | |
1116 | np->cork.rt = rt; | |
1117 | inet->cork.fl = *fl; | |
1118 | np->cork.hop_limit = hlimit; | |
41a1f8ea | 1119 | np->cork.tclass = tclass; |
628a5c56 JH |
1120 | mtu = np->pmtudisc == IPV6_PMTUDISC_PROBE ? |
1121 | rt->u.dst.dev->mtu : dst_mtu(rt->u.dst.path); | |
c7503609 | 1122 | if (np->frag_size < mtu) { |
d91675f9 YH |
1123 | if (np->frag_size) |
1124 | mtu = np->frag_size; | |
1125 | } | |
1126 | inet->cork.fragsize = mtu; | |
1da177e4 LT |
1127 | if (dst_allfrag(rt->u.dst.path)) |
1128 | inet->cork.flags |= IPCORK_ALLFRAG; | |
1129 | inet->cork.length = 0; | |
1130 | sk->sk_sndmsg_page = NULL; | |
1131 | sk->sk_sndmsg_off = 0; | |
01488942 | 1132 | exthdrlen = rt->u.dst.header_len + (opt ? opt->opt_flen : 0) - |
a1b05140 | 1133 | rt->rt6i_nfheader_len; |
1da177e4 LT |
1134 | length += exthdrlen; |
1135 | transhdrlen += exthdrlen; | |
1136 | } else { | |
1137 | rt = np->cork.rt; | |
1138 | fl = &inet->cork.fl; | |
1139 | if (inet->cork.flags & IPCORK_OPT) | |
1140 | opt = np->cork.opt; | |
1141 | transhdrlen = 0; | |
1142 | exthdrlen = 0; | |
1143 | mtu = inet->cork.fragsize; | |
1144 | } | |
1145 | ||
1146 | hh_len = LL_RESERVED_SPACE(rt->u.dst.dev); | |
1147 | ||
a1b05140 | 1148 | fragheaderlen = sizeof(struct ipv6hdr) + rt->rt6i_nfheader_len + |
b4ce9277 | 1149 | (opt ? opt->opt_nflen : 0); |
1da177e4 LT |
1150 | maxfraglen = ((mtu - fragheaderlen) & ~7) + fragheaderlen - sizeof(struct frag_hdr); |
1151 | ||
1152 | if (mtu <= sizeof(struct ipv6hdr) + IPV6_MAXPLEN) { | |
1153 | if (inet->cork.length + length > sizeof(struct ipv6hdr) + IPV6_MAXPLEN - fragheaderlen) { | |
1154 | ipv6_local_error(sk, EMSGSIZE, fl, mtu-exthdrlen); | |
1155 | return -EMSGSIZE; | |
1156 | } | |
1157 | } | |
1158 | ||
1159 | /* | |
1160 | * Let's try using as much space as possible. | |
1161 | * Use MTU if total length of the message fits into the MTU. | |
1162 | * Otherwise, we need to reserve fragment header and | |
1163 | * fragment alignment (= 8-15 octects, in total). | |
1164 | * | |
1165 | * Note that we may need to "move" the data from the tail of | |
1ab1457c | 1166 | * of the buffer to the new fragment when we split |
1da177e4 LT |
1167 | * the message. |
1168 | * | |
1ab1457c | 1169 | * FIXME: It may be fragmented into multiple chunks |
1da177e4 LT |
1170 | * at once if non-fragmentable extension headers |
1171 | * are too large. | |
1ab1457c | 1172 | * --yoshfuji |
1da177e4 LT |
1173 | */ |
1174 | ||
1175 | inet->cork.length += length; | |
e89e9cf5 AR |
1176 | if (((length > mtu) && (sk->sk_protocol == IPPROTO_UDP)) && |
1177 | (rt->u.dst.dev->features & NETIF_F_UFO)) { | |
1178 | ||
baa829d8 PM |
1179 | err = ip6_ufo_append_data(sk, getfrag, from, length, hh_len, |
1180 | fragheaderlen, transhdrlen, mtu, | |
1181 | flags); | |
1182 | if (err) | |
e89e9cf5 | 1183 | goto error; |
e89e9cf5 AR |
1184 | return 0; |
1185 | } | |
1da177e4 LT |
1186 | |
1187 | if ((skb = skb_peek_tail(&sk->sk_write_queue)) == NULL) | |
1188 | goto alloc_new_skb; | |
1189 | ||
1190 | while (length > 0) { | |
1191 | /* Check if the remaining data fits into current packet. */ | |
1192 | copy = (inet->cork.length <= mtu && !(inet->cork.flags & IPCORK_ALLFRAG) ? mtu : maxfraglen) - skb->len; | |
1193 | if (copy < length) | |
1194 | copy = maxfraglen - skb->len; | |
1195 | ||
1196 | if (copy <= 0) { | |
1197 | char *data; | |
1198 | unsigned int datalen; | |
1199 | unsigned int fraglen; | |
1200 | unsigned int fraggap; | |
1201 | unsigned int alloclen; | |
1202 | struct sk_buff *skb_prev; | |
1203 | alloc_new_skb: | |
1204 | skb_prev = skb; | |
1205 | ||
1206 | /* There's no room in the current skb */ | |
1207 | if (skb_prev) | |
1208 | fraggap = skb_prev->len - maxfraglen; | |
1209 | else | |
1210 | fraggap = 0; | |
1211 | ||
1212 | /* | |
1213 | * If remaining data exceeds the mtu, | |
1214 | * we know we need more fragment(s). | |
1215 | */ | |
1216 | datalen = length + fraggap; | |
1217 | if (datalen > (inet->cork.length <= mtu && !(inet->cork.flags & IPCORK_ALLFRAG) ? mtu : maxfraglen) - fragheaderlen) | |
1218 | datalen = maxfraglen - fragheaderlen; | |
1219 | ||
1220 | fraglen = datalen + fragheaderlen; | |
1221 | if ((flags & MSG_MORE) && | |
1222 | !(rt->u.dst.dev->features&NETIF_F_SG)) | |
1223 | alloclen = mtu; | |
1224 | else | |
1225 | alloclen = datalen + fragheaderlen; | |
1226 | ||
1227 | /* | |
1228 | * The last fragment gets additional space at tail. | |
1229 | * Note: we overallocate on fragments with MSG_MODE | |
1230 | * because we have no idea if we're the last one. | |
1231 | */ | |
1232 | if (datalen == length + fraggap) | |
1233 | alloclen += rt->u.dst.trailer_len; | |
1234 | ||
1235 | /* | |
1236 | * We just reserve space for fragment header. | |
1ab1457c | 1237 | * Note: this may be overallocation if the message |
1da177e4 LT |
1238 | * (without MSG_MORE) fits into the MTU. |
1239 | */ | |
1240 | alloclen += sizeof(struct frag_hdr); | |
1241 | ||
1242 | if (transhdrlen) { | |
1243 | skb = sock_alloc_send_skb(sk, | |
1244 | alloclen + hh_len, | |
1245 | (flags & MSG_DONTWAIT), &err); | |
1246 | } else { | |
1247 | skb = NULL; | |
1248 | if (atomic_read(&sk->sk_wmem_alloc) <= | |
1249 | 2 * sk->sk_sndbuf) | |
1250 | skb = sock_wmalloc(sk, | |
1251 | alloclen + hh_len, 1, | |
1252 | sk->sk_allocation); | |
1253 | if (unlikely(skb == NULL)) | |
1254 | err = -ENOBUFS; | |
1255 | } | |
1256 | if (skb == NULL) | |
1257 | goto error; | |
1258 | /* | |
1259 | * Fill in the control structures | |
1260 | */ | |
1261 | skb->ip_summed = csummode; | |
1262 | skb->csum = 0; | |
1263 | /* reserve for fragmentation */ | |
1264 | skb_reserve(skb, hh_len+sizeof(struct frag_hdr)); | |
1265 | ||
1266 | /* | |
1267 | * Find where to start putting bytes | |
1268 | */ | |
1269 | data = skb_put(skb, fraglen); | |
c14d2450 | 1270 | skb_set_network_header(skb, exthdrlen); |
1da177e4 | 1271 | data += fragheaderlen; |
b0e380b1 ACM |
1272 | skb->transport_header = (skb->network_header + |
1273 | fragheaderlen); | |
1da177e4 LT |
1274 | if (fraggap) { |
1275 | skb->csum = skb_copy_and_csum_bits( | |
1276 | skb_prev, maxfraglen, | |
1277 | data + transhdrlen, fraggap, 0); | |
1278 | skb_prev->csum = csum_sub(skb_prev->csum, | |
1279 | skb->csum); | |
1280 | data += fraggap; | |
e9fa4f7b | 1281 | pskb_trim_unique(skb_prev, maxfraglen); |
1da177e4 LT |
1282 | } |
1283 | copy = datalen - transhdrlen - fraggap; | |
1284 | if (copy < 0) { | |
1285 | err = -EINVAL; | |
1286 | kfree_skb(skb); | |
1287 | goto error; | |
1288 | } else if (copy > 0 && getfrag(from, data + transhdrlen, offset, copy, fraggap, skb) < 0) { | |
1289 | err = -EFAULT; | |
1290 | kfree_skb(skb); | |
1291 | goto error; | |
1292 | } | |
1293 | ||
1294 | offset += copy; | |
1295 | length -= datalen - fraggap; | |
1296 | transhdrlen = 0; | |
1297 | exthdrlen = 0; | |
1298 | csummode = CHECKSUM_NONE; | |
1299 | ||
1300 | /* | |
1301 | * Put the packet on the pending queue | |
1302 | */ | |
1303 | __skb_queue_tail(&sk->sk_write_queue, skb); | |
1304 | continue; | |
1305 | } | |
1306 | ||
1307 | if (copy > length) | |
1308 | copy = length; | |
1309 | ||
1310 | if (!(rt->u.dst.dev->features&NETIF_F_SG)) { | |
1311 | unsigned int off; | |
1312 | ||
1313 | off = skb->len; | |
1314 | if (getfrag(from, skb_put(skb, copy), | |
1315 | offset, copy, off, skb) < 0) { | |
1316 | __skb_trim(skb, off); | |
1317 | err = -EFAULT; | |
1318 | goto error; | |
1319 | } | |
1320 | } else { | |
1321 | int i = skb_shinfo(skb)->nr_frags; | |
1322 | skb_frag_t *frag = &skb_shinfo(skb)->frags[i-1]; | |
1323 | struct page *page = sk->sk_sndmsg_page; | |
1324 | int off = sk->sk_sndmsg_off; | |
1325 | unsigned int left; | |
1326 | ||
1327 | if (page && (left = PAGE_SIZE - off) > 0) { | |
1328 | if (copy >= left) | |
1329 | copy = left; | |
1330 | if (page != frag->page) { | |
1331 | if (i == MAX_SKB_FRAGS) { | |
1332 | err = -EMSGSIZE; | |
1333 | goto error; | |
1334 | } | |
1335 | get_page(page); | |
1336 | skb_fill_page_desc(skb, i, page, sk->sk_sndmsg_off, 0); | |
1337 | frag = &skb_shinfo(skb)->frags[i]; | |
1338 | } | |
1339 | } else if(i < MAX_SKB_FRAGS) { | |
1340 | if (copy > PAGE_SIZE) | |
1341 | copy = PAGE_SIZE; | |
1342 | page = alloc_pages(sk->sk_allocation, 0); | |
1343 | if (page == NULL) { | |
1344 | err = -ENOMEM; | |
1345 | goto error; | |
1346 | } | |
1347 | sk->sk_sndmsg_page = page; | |
1348 | sk->sk_sndmsg_off = 0; | |
1349 | ||
1350 | skb_fill_page_desc(skb, i, page, 0, 0); | |
1351 | frag = &skb_shinfo(skb)->frags[i]; | |
1da177e4 LT |
1352 | } else { |
1353 | err = -EMSGSIZE; | |
1354 | goto error; | |
1355 | } | |
1356 | if (getfrag(from, page_address(frag->page)+frag->page_offset+frag->size, offset, copy, skb->len, skb) < 0) { | |
1357 | err = -EFAULT; | |
1358 | goto error; | |
1359 | } | |
1360 | sk->sk_sndmsg_off += copy; | |
1361 | frag->size += copy; | |
1362 | skb->len += copy; | |
1363 | skb->data_len += copy; | |
f945fa7a HX |
1364 | skb->truesize += copy; |
1365 | atomic_add(copy, &sk->sk_wmem_alloc); | |
1da177e4 LT |
1366 | } |
1367 | offset += copy; | |
1368 | length -= copy; | |
1369 | } | |
1370 | return 0; | |
1371 | error: | |
1372 | inet->cork.length -= length; | |
a11d206d | 1373 | IP6_INC_STATS(rt->rt6i_idev, IPSTATS_MIB_OUTDISCARDS); |
1da177e4 LT |
1374 | return err; |
1375 | } | |
1376 | ||
bf138862 PE |
1377 | static void ip6_cork_release(struct inet_sock *inet, struct ipv6_pinfo *np) |
1378 | { | |
1379 | inet->cork.flags &= ~IPCORK_OPT; | |
1380 | kfree(np->cork.opt); | |
1381 | np->cork.opt = NULL; | |
1382 | if (np->cork.rt) { | |
1383 | dst_release(&np->cork.rt->u.dst); | |
1384 | np->cork.rt = NULL; | |
1385 | inet->cork.flags &= ~IPCORK_ALLFRAG; | |
1386 | } | |
1387 | memset(&inet->cork.fl, 0, sizeof(inet->cork.fl)); | |
1388 | } | |
1389 | ||
1da177e4 LT |
1390 | int ip6_push_pending_frames(struct sock *sk) |
1391 | { | |
1392 | struct sk_buff *skb, *tmp_skb; | |
1393 | struct sk_buff **tail_skb; | |
1394 | struct in6_addr final_dst_buf, *final_dst = &final_dst_buf; | |
1395 | struct inet_sock *inet = inet_sk(sk); | |
1396 | struct ipv6_pinfo *np = inet6_sk(sk); | |
1397 | struct ipv6hdr *hdr; | |
1398 | struct ipv6_txoptions *opt = np->cork.opt; | |
1399 | struct rt6_info *rt = np->cork.rt; | |
1400 | struct flowi *fl = &inet->cork.fl; | |
1401 | unsigned char proto = fl->proto; | |
1402 | int err = 0; | |
1403 | ||
1404 | if ((skb = __skb_dequeue(&sk->sk_write_queue)) == NULL) | |
1405 | goto out; | |
1406 | tail_skb = &(skb_shinfo(skb)->frag_list); | |
1407 | ||
1408 | /* move skb->data to ip header from ext header */ | |
d56f90a7 | 1409 | if (skb->data < skb_network_header(skb)) |
bbe735e4 | 1410 | __skb_pull(skb, skb_network_offset(skb)); |
1da177e4 | 1411 | while ((tmp_skb = __skb_dequeue(&sk->sk_write_queue)) != NULL) { |
cfe1fc77 | 1412 | __skb_pull(tmp_skb, skb_network_header_len(skb)); |
1da177e4 LT |
1413 | *tail_skb = tmp_skb; |
1414 | tail_skb = &(tmp_skb->next); | |
1415 | skb->len += tmp_skb->len; | |
1416 | skb->data_len += tmp_skb->len; | |
1da177e4 LT |
1417 | skb->truesize += tmp_skb->truesize; |
1418 | __sock_put(tmp_skb->sk); | |
1419 | tmp_skb->destructor = NULL; | |
1420 | tmp_skb->sk = NULL; | |
1da177e4 LT |
1421 | } |
1422 | ||
28a89453 | 1423 | /* Allow local fragmentation. */ |
b5c15fc0 | 1424 | if (np->pmtudisc < IPV6_PMTUDISC_DO) |
28a89453 HX |
1425 | skb->local_df = 1; |
1426 | ||
1da177e4 | 1427 | ipv6_addr_copy(final_dst, &fl->fl6_dst); |
cfe1fc77 | 1428 | __skb_pull(skb, skb_network_header_len(skb)); |
1da177e4 LT |
1429 | if (opt && opt->opt_flen) |
1430 | ipv6_push_frag_opts(skb, opt, &proto); | |
1431 | if (opt && opt->opt_nflen) | |
1432 | ipv6_push_nfrag_opts(skb, opt, &proto, &final_dst); | |
1433 | ||
e2d1bca7 ACM |
1434 | skb_push(skb, sizeof(struct ipv6hdr)); |
1435 | skb_reset_network_header(skb); | |
0660e03f | 1436 | hdr = ipv6_hdr(skb); |
1ab1457c | 1437 | |
90bcaf7b | 1438 | *(__be32*)hdr = fl->fl6_flowlabel | |
41a1f8ea | 1439 | htonl(0x60000000 | ((int)np->cork.tclass << 20)); |
1da177e4 | 1440 | |
1da177e4 LT |
1441 | hdr->hop_limit = np->cork.hop_limit; |
1442 | hdr->nexthdr = proto; | |
1443 | ipv6_addr_copy(&hdr->saddr, &fl->fl6_src); | |
1444 | ipv6_addr_copy(&hdr->daddr, final_dst); | |
1445 | ||
a2c2064f | 1446 | skb->priority = sk->sk_priority; |
4a19ec58 | 1447 | skb->mark = sk->sk_mark; |
a2c2064f | 1448 | |
1da177e4 | 1449 | skb->dst = dst_clone(&rt->u.dst); |
a11d206d | 1450 | IP6_INC_STATS(rt->rt6i_idev, IPSTATS_MIB_OUTREQUESTS); |
14878f75 DS |
1451 | if (proto == IPPROTO_ICMPV6) { |
1452 | struct inet6_dev *idev = ip6_dst_idev(skb->dst); | |
1453 | ||
1454 | ICMP6MSGOUT_INC_STATS_BH(idev, icmp6_hdr(skb)->icmp6_type); | |
1455 | ICMP6_INC_STATS_BH(idev, ICMP6_MIB_OUTMSGS); | |
1456 | } | |
1457 | ||
ef76bc23 | 1458 | err = ip6_local_out(skb); |
1da177e4 LT |
1459 | if (err) { |
1460 | if (err > 0) | |
3320da89 | 1461 | err = np->recverr ? net_xmit_errno(err) : 0; |
1da177e4 LT |
1462 | if (err) |
1463 | goto error; | |
1464 | } | |
1465 | ||
1466 | out: | |
bf138862 | 1467 | ip6_cork_release(inet, np); |
1da177e4 LT |
1468 | return err; |
1469 | error: | |
1470 | goto out; | |
1471 | } | |
1472 | ||
1473 | void ip6_flush_pending_frames(struct sock *sk) | |
1474 | { | |
1da177e4 LT |
1475 | struct sk_buff *skb; |
1476 | ||
1477 | while ((skb = __skb_dequeue_tail(&sk->sk_write_queue)) != NULL) { | |
e1f52208 YH |
1478 | if (skb->dst) |
1479 | IP6_INC_STATS(ip6_dst_idev(skb->dst), | |
1480 | IPSTATS_MIB_OUTDISCARDS); | |
1da177e4 LT |
1481 | kfree_skb(skb); |
1482 | } | |
1483 | ||
bf138862 | 1484 | ip6_cork_release(inet_sk(sk), inet6_sk(sk)); |
1da177e4 | 1485 | } |