]>
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 PM |
259 | skb->priority = sk->sk_priority; |
260 | ||
1da177e4 | 261 | mtu = dst_mtu(dst); |
89114afd | 262 | if ((skb->len <= mtu) || ipfragok || skb_is_gso(skb)) { |
a11d206d YH |
263 | IP6_INC_STATS(ip6_dst_idev(skb->dst), |
264 | IPSTATS_MIB_OUTREQUESTS); | |
6e23ae2a | 265 | return NF_HOOK(PF_INET6, NF_INET_LOCAL_OUT, skb, NULL, dst->dev, |
6869c4d8 | 266 | dst_output); |
1da177e4 LT |
267 | } |
268 | ||
269 | if (net_ratelimit()) | |
270 | printk(KERN_DEBUG "IPv6: sending pkt_too_big to self\n"); | |
271 | skb->dev = dst->dev; | |
272 | icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu, skb->dev); | |
a11d206d | 273 | IP6_INC_STATS(ip6_dst_idev(skb->dst), IPSTATS_MIB_FRAGFAILS); |
1da177e4 LT |
274 | kfree_skb(skb); |
275 | return -EMSGSIZE; | |
276 | } | |
277 | ||
7159039a YH |
278 | EXPORT_SYMBOL(ip6_xmit); |
279 | ||
1da177e4 LT |
280 | /* |
281 | * To avoid extra problems ND packets are send through this | |
282 | * routine. It's code duplication but I really want to avoid | |
283 | * extra checks since ipv6_build_header is used by TCP (which | |
284 | * is for us performance critical) | |
285 | */ | |
286 | ||
287 | int ip6_nd_hdr(struct sock *sk, struct sk_buff *skb, struct net_device *dev, | |
288 | struct in6_addr *saddr, struct in6_addr *daddr, | |
289 | int proto, int len) | |
290 | { | |
291 | struct ipv6_pinfo *np = inet6_sk(sk); | |
292 | struct ipv6hdr *hdr; | |
293 | int totlen; | |
294 | ||
295 | skb->protocol = htons(ETH_P_IPV6); | |
296 | skb->dev = dev; | |
297 | ||
298 | totlen = len + sizeof(struct ipv6hdr); | |
299 | ||
55f79cc0 ACM |
300 | skb_reset_network_header(skb); |
301 | skb_put(skb, sizeof(struct ipv6hdr)); | |
0660e03f | 302 | hdr = ipv6_hdr(skb); |
1da177e4 | 303 | |
ae08e1f0 | 304 | *(__be32*)hdr = htonl(0x60000000); |
1da177e4 LT |
305 | |
306 | hdr->payload_len = htons(len); | |
307 | hdr->nexthdr = proto; | |
308 | hdr->hop_limit = np->hop_limit; | |
309 | ||
310 | ipv6_addr_copy(&hdr->saddr, saddr); | |
311 | ipv6_addr_copy(&hdr->daddr, daddr); | |
312 | ||
313 | return 0; | |
314 | } | |
315 | ||
316 | static int ip6_call_ra_chain(struct sk_buff *skb, int sel) | |
317 | { | |
318 | struct ip6_ra_chain *ra; | |
319 | struct sock *last = NULL; | |
320 | ||
321 | read_lock(&ip6_ra_lock); | |
322 | for (ra = ip6_ra_chain; ra; ra = ra->next) { | |
323 | struct sock *sk = ra->sk; | |
0bd1b59b AM |
324 | if (sk && ra->sel == sel && |
325 | (!sk->sk_bound_dev_if || | |
326 | sk->sk_bound_dev_if == skb->dev->ifindex)) { | |
1da177e4 LT |
327 | if (last) { |
328 | struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC); | |
329 | if (skb2) | |
330 | rawv6_rcv(last, skb2); | |
331 | } | |
332 | last = sk; | |
333 | } | |
334 | } | |
335 | ||
336 | if (last) { | |
337 | rawv6_rcv(last, skb); | |
338 | read_unlock(&ip6_ra_lock); | |
339 | return 1; | |
340 | } | |
341 | read_unlock(&ip6_ra_lock); | |
342 | return 0; | |
343 | } | |
344 | ||
e21e0b5f VN |
345 | static int ip6_forward_proxy_check(struct sk_buff *skb) |
346 | { | |
0660e03f | 347 | struct ipv6hdr *hdr = ipv6_hdr(skb); |
e21e0b5f VN |
348 | u8 nexthdr = hdr->nexthdr; |
349 | int offset; | |
350 | ||
351 | if (ipv6_ext_hdr(nexthdr)) { | |
352 | offset = ipv6_skip_exthdr(skb, sizeof(*hdr), &nexthdr); | |
353 | if (offset < 0) | |
354 | return 0; | |
355 | } else | |
356 | offset = sizeof(struct ipv6hdr); | |
357 | ||
358 | if (nexthdr == IPPROTO_ICMPV6) { | |
359 | struct icmp6hdr *icmp6; | |
360 | ||
d56f90a7 ACM |
361 | if (!pskb_may_pull(skb, (skb_network_header(skb) + |
362 | offset + 1 - skb->data))) | |
e21e0b5f VN |
363 | return 0; |
364 | ||
d56f90a7 | 365 | icmp6 = (struct icmp6hdr *)(skb_network_header(skb) + offset); |
e21e0b5f VN |
366 | |
367 | switch (icmp6->icmp6_type) { | |
368 | case NDISC_ROUTER_SOLICITATION: | |
369 | case NDISC_ROUTER_ADVERTISEMENT: | |
370 | case NDISC_NEIGHBOUR_SOLICITATION: | |
371 | case NDISC_NEIGHBOUR_ADVERTISEMENT: | |
372 | case NDISC_REDIRECT: | |
373 | /* For reaction involving unicast neighbor discovery | |
374 | * message destined to the proxied address, pass it to | |
375 | * input function. | |
376 | */ | |
377 | return 1; | |
378 | default: | |
379 | break; | |
380 | } | |
381 | } | |
382 | ||
74553b09 VN |
383 | /* |
384 | * The proxying router can't forward traffic sent to a link-local | |
385 | * address, so signal the sender and discard the packet. This | |
386 | * behavior is clarified by the MIPv6 specification. | |
387 | */ | |
388 | if (ipv6_addr_type(&hdr->daddr) & IPV6_ADDR_LINKLOCAL) { | |
389 | dst_link_failure(skb); | |
390 | return -1; | |
391 | } | |
392 | ||
e21e0b5f VN |
393 | return 0; |
394 | } | |
395 | ||
1da177e4 LT |
396 | static inline int ip6_forward_finish(struct sk_buff *skb) |
397 | { | |
398 | return dst_output(skb); | |
399 | } | |
400 | ||
401 | int ip6_forward(struct sk_buff *skb) | |
402 | { | |
403 | struct dst_entry *dst = skb->dst; | |
0660e03f | 404 | struct ipv6hdr *hdr = ipv6_hdr(skb); |
1da177e4 | 405 | struct inet6_skb_parm *opt = IP6CB(skb); |
1ab1457c | 406 | |
1da177e4 LT |
407 | if (ipv6_devconf.forwarding == 0) |
408 | goto error; | |
409 | ||
410 | if (!xfrm6_policy_check(NULL, XFRM_POLICY_FWD, skb)) { | |
a11d206d | 411 | IP6_INC_STATS(ip6_dst_idev(dst), IPSTATS_MIB_INDISCARDS); |
1da177e4 LT |
412 | goto drop; |
413 | } | |
414 | ||
35fc92a9 | 415 | skb_forward_csum(skb); |
1da177e4 LT |
416 | |
417 | /* | |
418 | * We DO NOT make any processing on | |
419 | * RA packets, pushing them to user level AS IS | |
420 | * without ane WARRANTY that application will be able | |
421 | * to interpret them. The reason is that we | |
422 | * cannot make anything clever here. | |
423 | * | |
424 | * We are not end-node, so that if packet contains | |
425 | * AH/ESP, we cannot make anything. | |
426 | * Defragmentation also would be mistake, RA packets | |
427 | * cannot be fragmented, because there is no warranty | |
428 | * that different fragments will go along one path. --ANK | |
429 | */ | |
430 | if (opt->ra) { | |
d56f90a7 | 431 | u8 *ptr = skb_network_header(skb) + opt->ra; |
1da177e4 LT |
432 | if (ip6_call_ra_chain(skb, (ptr[2]<<8) + ptr[3])) |
433 | return 0; | |
434 | } | |
435 | ||
436 | /* | |
437 | * check and decrement ttl | |
438 | */ | |
439 | if (hdr->hop_limit <= 1) { | |
440 | /* Force OUTPUT device used as source address */ | |
441 | skb->dev = dst->dev; | |
442 | icmpv6_send(skb, ICMPV6_TIME_EXCEED, ICMPV6_EXC_HOPLIMIT, | |
443 | 0, skb->dev); | |
a11d206d | 444 | IP6_INC_STATS_BH(ip6_dst_idev(dst), IPSTATS_MIB_INHDRERRORS); |
1da177e4 LT |
445 | |
446 | kfree_skb(skb); | |
447 | return -ETIMEDOUT; | |
448 | } | |
449 | ||
fbea49e1 YH |
450 | /* XXX: idev->cnf.proxy_ndp? */ |
451 | if (ipv6_devconf.proxy_ndp && | |
426b5303 | 452 | pneigh_lookup(&nd_tbl, &init_net, &hdr->daddr, skb->dev, 0)) { |
74553b09 VN |
453 | int proxied = ip6_forward_proxy_check(skb); |
454 | if (proxied > 0) | |
e21e0b5f | 455 | return ip6_input(skb); |
74553b09 | 456 | else if (proxied < 0) { |
a11d206d | 457 | IP6_INC_STATS(ip6_dst_idev(dst), IPSTATS_MIB_INDISCARDS); |
74553b09 VN |
458 | goto drop; |
459 | } | |
e21e0b5f VN |
460 | } |
461 | ||
1da177e4 | 462 | if (!xfrm6_route_forward(skb)) { |
a11d206d | 463 | IP6_INC_STATS(ip6_dst_idev(dst), IPSTATS_MIB_INDISCARDS); |
1da177e4 LT |
464 | goto drop; |
465 | } | |
466 | dst = skb->dst; | |
467 | ||
468 | /* IPv6 specs say nothing about it, but it is clear that we cannot | |
469 | send redirects to source routed frames. | |
1e5dc146 | 470 | We don't send redirects to frames decapsulated from IPsec. |
1da177e4 | 471 | */ |
1e5dc146 MN |
472 | if (skb->dev == dst->dev && dst->neighbour && opt->srcrt == 0 && |
473 | !skb->sp) { | |
1da177e4 LT |
474 | struct in6_addr *target = NULL; |
475 | struct rt6_info *rt; | |
476 | struct neighbour *n = dst->neighbour; | |
477 | ||
478 | /* | |
479 | * incoming and outgoing devices are the same | |
480 | * send a redirect. | |
481 | */ | |
482 | ||
483 | rt = (struct rt6_info *) dst; | |
484 | if ((rt->rt6i_flags & RTF_GATEWAY)) | |
485 | target = (struct in6_addr*)&n->primary_key; | |
486 | else | |
487 | target = &hdr->daddr; | |
488 | ||
489 | /* Limit redirects both by destination (here) | |
490 | and by source (inside ndisc_send_redirect) | |
491 | */ | |
492 | if (xrlim_allow(dst, 1*HZ)) | |
493 | ndisc_send_redirect(skb, n, target); | |
5bb1ab09 DS |
494 | } else { |
495 | int addrtype = ipv6_addr_type(&hdr->saddr); | |
496 | ||
1da177e4 | 497 | /* This check is security critical. */ |
5bb1ab09 DS |
498 | if (addrtype & (IPV6_ADDR_MULTICAST|IPV6_ADDR_LOOPBACK)) |
499 | goto error; | |
500 | if (addrtype & IPV6_ADDR_LINKLOCAL) { | |
501 | icmpv6_send(skb, ICMPV6_DEST_UNREACH, | |
502 | ICMPV6_NOT_NEIGHBOUR, 0, skb->dev); | |
503 | goto error; | |
504 | } | |
1da177e4 LT |
505 | } |
506 | ||
507 | if (skb->len > dst_mtu(dst)) { | |
508 | /* Again, force OUTPUT device used as source address */ | |
509 | skb->dev = dst->dev; | |
510 | icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, dst_mtu(dst), skb->dev); | |
a11d206d YH |
511 | IP6_INC_STATS_BH(ip6_dst_idev(dst), IPSTATS_MIB_INTOOBIGERRORS); |
512 | IP6_INC_STATS_BH(ip6_dst_idev(dst), IPSTATS_MIB_FRAGFAILS); | |
1da177e4 LT |
513 | kfree_skb(skb); |
514 | return -EMSGSIZE; | |
515 | } | |
516 | ||
517 | if (skb_cow(skb, dst->dev->hard_header_len)) { | |
a11d206d | 518 | IP6_INC_STATS(ip6_dst_idev(dst), IPSTATS_MIB_OUTDISCARDS); |
1da177e4 LT |
519 | goto drop; |
520 | } | |
521 | ||
0660e03f | 522 | hdr = ipv6_hdr(skb); |
1da177e4 LT |
523 | |
524 | /* Mangling hops number delayed to point after skb COW */ | |
1ab1457c | 525 | |
1da177e4 LT |
526 | hdr->hop_limit--; |
527 | ||
a11d206d | 528 | IP6_INC_STATS_BH(ip6_dst_idev(dst), IPSTATS_MIB_OUTFORWDATAGRAMS); |
6e23ae2a PM |
529 | return NF_HOOK(PF_INET6, NF_INET_FORWARD, skb, skb->dev, dst->dev, |
530 | ip6_forward_finish); | |
1da177e4 LT |
531 | |
532 | error: | |
a11d206d | 533 | IP6_INC_STATS_BH(ip6_dst_idev(dst), IPSTATS_MIB_INADDRERRORS); |
1da177e4 LT |
534 | drop: |
535 | kfree_skb(skb); | |
536 | return -EINVAL; | |
537 | } | |
538 | ||
539 | static void ip6_copy_metadata(struct sk_buff *to, struct sk_buff *from) | |
540 | { | |
541 | to->pkt_type = from->pkt_type; | |
542 | to->priority = from->priority; | |
543 | to->protocol = from->protocol; | |
1da177e4 LT |
544 | dst_release(to->dst); |
545 | to->dst = dst_clone(from->dst); | |
546 | to->dev = from->dev; | |
82e91ffe | 547 | to->mark = from->mark; |
1da177e4 LT |
548 | |
549 | #ifdef CONFIG_NET_SCHED | |
550 | to->tc_index = from->tc_index; | |
551 | #endif | |
e7ac05f3 | 552 | nf_copy(to, from); |
ba9dda3a JK |
553 | #if defined(CONFIG_NETFILTER_XT_TARGET_TRACE) || \ |
554 | defined(CONFIG_NETFILTER_XT_TARGET_TRACE_MODULE) | |
555 | to->nf_trace = from->nf_trace; | |
556 | #endif | |
984bc16c | 557 | skb_copy_secmark(to, from); |
1da177e4 LT |
558 | } |
559 | ||
560 | int ip6_find_1stfragopt(struct sk_buff *skb, u8 **nexthdr) | |
561 | { | |
562 | u16 offset = sizeof(struct ipv6hdr); | |
0660e03f ACM |
563 | struct ipv6_opt_hdr *exthdr = |
564 | (struct ipv6_opt_hdr *)(ipv6_hdr(skb) + 1); | |
27a884dc | 565 | unsigned int packet_len = skb->tail - skb->network_header; |
1da177e4 | 566 | int found_rhdr = 0; |
0660e03f | 567 | *nexthdr = &ipv6_hdr(skb)->nexthdr; |
1da177e4 LT |
568 | |
569 | while (offset + 1 <= packet_len) { | |
570 | ||
571 | switch (**nexthdr) { | |
572 | ||
573 | case NEXTHDR_HOP: | |
27637df9 | 574 | break; |
1da177e4 | 575 | case NEXTHDR_ROUTING: |
27637df9 MN |
576 | found_rhdr = 1; |
577 | break; | |
1da177e4 | 578 | case NEXTHDR_DEST: |
59fbb3a6 | 579 | #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE) |
27637df9 MN |
580 | if (ipv6_find_tlv(skb, offset, IPV6_TLV_HAO) >= 0) |
581 | break; | |
582 | #endif | |
583 | if (found_rhdr) | |
584 | return offset; | |
1da177e4 LT |
585 | break; |
586 | default : | |
587 | return offset; | |
588 | } | |
27637df9 MN |
589 | |
590 | offset += ipv6_optlen(exthdr); | |
591 | *nexthdr = &exthdr->nexthdr; | |
d56f90a7 ACM |
592 | exthdr = (struct ipv6_opt_hdr *)(skb_network_header(skb) + |
593 | offset); | |
1da177e4 LT |
594 | } |
595 | ||
596 | return offset; | |
597 | } | |
b59f45d0 | 598 | EXPORT_SYMBOL_GPL(ip6_find_1stfragopt); |
1da177e4 LT |
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 | */ | |
623 | if (!np || np->pmtudisc >= IPV6_PMTUDISC_DO) { | |
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); | |
639 | ||
640 | if (first_len - hlen > mtu || | |
641 | ((first_len - hlen) & 7) || | |
642 | skb_cloned(skb)) | |
643 | goto slow_path; | |
644 | ||
645 | for (frag = skb_shinfo(skb)->frag_list; frag; frag = frag->next) { | |
646 | /* Correct geometry. */ | |
647 | if (frag->len > mtu || | |
648 | ((frag->len & 7) && frag->next) || | |
649 | skb_headroom(frag) < hlen) | |
650 | goto slow_path; | |
651 | ||
1da177e4 LT |
652 | /* Partially cloned skb? */ |
653 | if (skb_shared(frag)) | |
654 | goto slow_path; | |
2fdba6b0 HX |
655 | |
656 | BUG_ON(frag->sk); | |
657 | if (skb->sk) { | |
658 | sock_hold(skb->sk); | |
659 | frag->sk = skb->sk; | |
660 | frag->destructor = sock_wfree; | |
661 | skb->truesize -= frag->truesize; | |
662 | } | |
1da177e4 LT |
663 | } |
664 | ||
665 | err = 0; | |
666 | offset = 0; | |
667 | frag = skb_shinfo(skb)->frag_list; | |
668 | skb_shinfo(skb)->frag_list = NULL; | |
669 | /* BUILD HEADER */ | |
670 | ||
9a217a1c | 671 | *prevhdr = NEXTHDR_FRAGMENT; |
d56f90a7 | 672 | tmp_hdr = kmemdup(skb_network_header(skb), hlen, GFP_ATOMIC); |
1da177e4 | 673 | if (!tmp_hdr) { |
a11d206d | 674 | IP6_INC_STATS(ip6_dst_idev(skb->dst), IPSTATS_MIB_FRAGFAILS); |
1da177e4 LT |
675 | return -ENOMEM; |
676 | } | |
677 | ||
1da177e4 LT |
678 | __skb_pull(skb, hlen); |
679 | fh = (struct frag_hdr*)__skb_push(skb, sizeof(struct frag_hdr)); | |
e2d1bca7 ACM |
680 | __skb_push(skb, hlen); |
681 | skb_reset_network_header(skb); | |
d56f90a7 | 682 | memcpy(skb_network_header(skb), tmp_hdr, hlen); |
1da177e4 LT |
683 | |
684 | ipv6_select_ident(skb, fh); | |
685 | fh->nexthdr = nexthdr; | |
686 | fh->reserved = 0; | |
687 | fh->frag_off = htons(IP6_MF); | |
688 | frag_id = fh->identification; | |
689 | ||
690 | first_len = skb_pagelen(skb); | |
691 | skb->data_len = first_len - skb_headlen(skb); | |
692 | skb->len = first_len; | |
0660e03f ACM |
693 | ipv6_hdr(skb)->payload_len = htons(first_len - |
694 | sizeof(struct ipv6hdr)); | |
a11d206d YH |
695 | |
696 | dst_hold(&rt->u.dst); | |
1da177e4 LT |
697 | |
698 | for (;;) { | |
699 | /* Prepare header of the next frame, | |
700 | * before previous one went down. */ | |
701 | if (frag) { | |
702 | frag->ip_summed = CHECKSUM_NONE; | |
badff6d0 | 703 | skb_reset_transport_header(frag); |
1da177e4 | 704 | fh = (struct frag_hdr*)__skb_push(frag, sizeof(struct frag_hdr)); |
e2d1bca7 ACM |
705 | __skb_push(frag, hlen); |
706 | skb_reset_network_header(frag); | |
d56f90a7 ACM |
707 | memcpy(skb_network_header(frag), tmp_hdr, |
708 | hlen); | |
1da177e4 LT |
709 | offset += skb->len - hlen - sizeof(struct frag_hdr); |
710 | fh->nexthdr = nexthdr; | |
711 | fh->reserved = 0; | |
712 | fh->frag_off = htons(offset); | |
713 | if (frag->next != NULL) | |
714 | fh->frag_off |= htons(IP6_MF); | |
715 | fh->identification = frag_id; | |
0660e03f ACM |
716 | ipv6_hdr(frag)->payload_len = |
717 | htons(frag->len - | |
718 | sizeof(struct ipv6hdr)); | |
1da177e4 LT |
719 | ip6_copy_metadata(frag, skb); |
720 | } | |
1ab1457c | 721 | |
1da177e4 | 722 | err = output(skb); |
dafee490 | 723 | if(!err) |
a11d206d | 724 | IP6_INC_STATS(ip6_dst_idev(&rt->u.dst), IPSTATS_MIB_FRAGCREATES); |
dafee490 | 725 | |
1da177e4 LT |
726 | if (err || !frag) |
727 | break; | |
728 | ||
729 | skb = frag; | |
730 | frag = skb->next; | |
731 | skb->next = NULL; | |
732 | } | |
733 | ||
a51482bd | 734 | kfree(tmp_hdr); |
1da177e4 LT |
735 | |
736 | if (err == 0) { | |
a11d206d YH |
737 | IP6_INC_STATS(ip6_dst_idev(&rt->u.dst), IPSTATS_MIB_FRAGOKS); |
738 | dst_release(&rt->u.dst); | |
1da177e4 LT |
739 | return 0; |
740 | } | |
741 | ||
742 | while (frag) { | |
743 | skb = frag->next; | |
744 | kfree_skb(frag); | |
745 | frag = skb; | |
746 | } | |
747 | ||
a11d206d YH |
748 | IP6_INC_STATS(ip6_dst_idev(&rt->u.dst), IPSTATS_MIB_FRAGFAILS); |
749 | dst_release(&rt->u.dst); | |
1da177e4 LT |
750 | return err; |
751 | } | |
752 | ||
753 | slow_path: | |
754 | left = skb->len - hlen; /* Space per frame */ | |
755 | ptr = hlen; /* Where to start from */ | |
756 | ||
757 | /* | |
758 | * Fragment the datagram. | |
759 | */ | |
760 | ||
761 | *prevhdr = NEXTHDR_FRAGMENT; | |
762 | ||
763 | /* | |
764 | * Keep copying data until we run out. | |
765 | */ | |
766 | while(left > 0) { | |
767 | len = left; | |
768 | /* IF: it doesn't fit, use 'mtu' - the data space left */ | |
769 | if (len > mtu) | |
770 | len = mtu; | |
771 | /* IF: we are not sending upto and including the packet end | |
772 | then align the next start on an eight byte boundary */ | |
773 | if (len < left) { | |
774 | len &= ~7; | |
775 | } | |
776 | /* | |
777 | * Allocate buffer. | |
778 | */ | |
779 | ||
780 | if ((frag = alloc_skb(len+hlen+sizeof(struct frag_hdr)+LL_RESERVED_SPACE(rt->u.dst.dev), GFP_ATOMIC)) == NULL) { | |
64ce2073 | 781 | NETDEBUG(KERN_INFO "IPv6: frag: no memory for new fragment!\n"); |
a11d206d YH |
782 | IP6_INC_STATS(ip6_dst_idev(skb->dst), |
783 | IPSTATS_MIB_FRAGFAILS); | |
1da177e4 LT |
784 | err = -ENOMEM; |
785 | goto fail; | |
786 | } | |
787 | ||
788 | /* | |
789 | * Set up data on packet | |
790 | */ | |
791 | ||
792 | ip6_copy_metadata(frag, skb); | |
793 | skb_reserve(frag, LL_RESERVED_SPACE(rt->u.dst.dev)); | |
794 | skb_put(frag, len + hlen + sizeof(struct frag_hdr)); | |
c1d2bbe1 | 795 | skb_reset_network_header(frag); |
badff6d0 | 796 | fh = (struct frag_hdr *)(skb_network_header(frag) + hlen); |
b0e380b1 ACM |
797 | frag->transport_header = (frag->network_header + hlen + |
798 | sizeof(struct frag_hdr)); | |
1da177e4 LT |
799 | |
800 | /* | |
801 | * Charge the memory for the fragment to any owner | |
802 | * it might possess | |
803 | */ | |
804 | if (skb->sk) | |
805 | skb_set_owner_w(frag, skb->sk); | |
806 | ||
807 | /* | |
808 | * Copy the packet header into the new buffer. | |
809 | */ | |
d626f62b | 810 | skb_copy_from_linear_data(skb, skb_network_header(frag), hlen); |
1da177e4 LT |
811 | |
812 | /* | |
813 | * Build fragment header. | |
814 | */ | |
815 | fh->nexthdr = nexthdr; | |
816 | fh->reserved = 0; | |
f36d6ab1 | 817 | if (!frag_id) { |
1da177e4 LT |
818 | ipv6_select_ident(skb, fh); |
819 | frag_id = fh->identification; | |
820 | } else | |
821 | fh->identification = frag_id; | |
822 | ||
823 | /* | |
824 | * Copy a block of the IP datagram. | |
825 | */ | |
8984e41d | 826 | if (skb_copy_bits(skb, ptr, skb_transport_header(frag), len)) |
1da177e4 LT |
827 | BUG(); |
828 | left -= len; | |
829 | ||
830 | fh->frag_off = htons(offset); | |
831 | if (left > 0) | |
832 | fh->frag_off |= htons(IP6_MF); | |
0660e03f ACM |
833 | ipv6_hdr(frag)->payload_len = htons(frag->len - |
834 | sizeof(struct ipv6hdr)); | |
1da177e4 LT |
835 | |
836 | ptr += len; | |
837 | offset += len; | |
838 | ||
839 | /* | |
840 | * Put this fragment into the sending queue. | |
841 | */ | |
1da177e4 LT |
842 | err = output(frag); |
843 | if (err) | |
844 | goto fail; | |
dafee490 | 845 | |
a11d206d | 846 | IP6_INC_STATS(ip6_dst_idev(skb->dst), IPSTATS_MIB_FRAGCREATES); |
1da177e4 | 847 | } |
a11d206d YH |
848 | IP6_INC_STATS(ip6_dst_idev(skb->dst), |
849 | IPSTATS_MIB_FRAGOKS); | |
1da177e4 | 850 | kfree_skb(skb); |
1da177e4 LT |
851 | return err; |
852 | ||
853 | fail: | |
a11d206d YH |
854 | IP6_INC_STATS(ip6_dst_idev(skb->dst), |
855 | IPSTATS_MIB_FRAGFAILS); | |
1ab1457c | 856 | kfree_skb(skb); |
1da177e4 LT |
857 | return err; |
858 | } | |
859 | ||
cf6b1982 YH |
860 | static inline int ip6_rt_check(struct rt6key *rt_key, |
861 | struct in6_addr *fl_addr, | |
862 | struct in6_addr *addr_cache) | |
863 | { | |
864 | return ((rt_key->plen != 128 || !ipv6_addr_equal(fl_addr, &rt_key->addr)) && | |
865 | (addr_cache == NULL || !ipv6_addr_equal(fl_addr, addr_cache))); | |
866 | } | |
867 | ||
497c615a HX |
868 | static struct dst_entry *ip6_sk_dst_check(struct sock *sk, |
869 | struct dst_entry *dst, | |
870 | struct flowi *fl) | |
1da177e4 | 871 | { |
497c615a HX |
872 | struct ipv6_pinfo *np = inet6_sk(sk); |
873 | struct rt6_info *rt = (struct rt6_info *)dst; | |
1da177e4 | 874 | |
497c615a HX |
875 | if (!dst) |
876 | goto out; | |
877 | ||
878 | /* Yes, checking route validity in not connected | |
879 | * case is not very simple. Take into account, | |
880 | * that we do not support routing by source, TOS, | |
881 | * and MSG_DONTROUTE --ANK (980726) | |
882 | * | |
cf6b1982 YH |
883 | * 1. ip6_rt_check(): If route was host route, |
884 | * check that cached destination is current. | |
497c615a HX |
885 | * If it is network route, we still may |
886 | * check its validity using saved pointer | |
887 | * to the last used address: daddr_cache. | |
888 | * We do not want to save whole address now, | |
889 | * (because main consumer of this service | |
890 | * is tcp, which has not this problem), | |
891 | * so that the last trick works only on connected | |
892 | * sockets. | |
893 | * 2. oif also should be the same. | |
894 | */ | |
cf6b1982 | 895 | if (ip6_rt_check(&rt->rt6i_dst, &fl->fl6_dst, np->daddr_cache) || |
8e1ef0a9 YH |
896 | #ifdef CONFIG_IPV6_SUBTREES |
897 | ip6_rt_check(&rt->rt6i_src, &fl->fl6_src, np->saddr_cache) || | |
898 | #endif | |
cf6b1982 | 899 | (fl->oif && fl->oif != dst->dev->ifindex)) { |
497c615a HX |
900 | dst_release(dst); |
901 | dst = NULL; | |
1da177e4 LT |
902 | } |
903 | ||
497c615a HX |
904 | out: |
905 | return dst; | |
906 | } | |
907 | ||
908 | static int ip6_dst_lookup_tail(struct sock *sk, | |
909 | struct dst_entry **dst, struct flowi *fl) | |
910 | { | |
911 | int err; | |
912 | ||
1da177e4 LT |
913 | if (*dst == NULL) |
914 | *dst = ip6_route_output(sk, fl); | |
915 | ||
916 | if ((err = (*dst)->error)) | |
917 | goto out_err_release; | |
918 | ||
919 | if (ipv6_addr_any(&fl->fl6_src)) { | |
920 | err = ipv6_get_saddr(*dst, &fl->fl6_dst, &fl->fl6_src); | |
44456d37 | 921 | if (err) |
1da177e4 | 922 | goto out_err_release; |
1da177e4 LT |
923 | } |
924 | ||
95c385b4 NH |
925 | #ifdef CONFIG_IPV6_OPTIMISTIC_DAD |
926 | /* | |
927 | * Here if the dst entry we've looked up | |
928 | * has a neighbour entry that is in the INCOMPLETE | |
929 | * state and the src address from the flow is | |
930 | * marked as OPTIMISTIC, we release the found | |
931 | * dst entry and replace it instead with the | |
932 | * dst entry of the nexthop router | |
933 | */ | |
934 | if (!((*dst)->neighbour->nud_state & NUD_VALID)) { | |
935 | struct inet6_ifaddr *ifp; | |
936 | struct flowi fl_gw; | |
937 | int redirect; | |
938 | ||
939 | ifp = ipv6_get_ifaddr(&fl->fl6_src, (*dst)->dev, 1); | |
940 | ||
941 | redirect = (ifp && ifp->flags & IFA_F_OPTIMISTIC); | |
942 | if (ifp) | |
943 | in6_ifa_put(ifp); | |
944 | ||
945 | if (redirect) { | |
946 | /* | |
947 | * We need to get the dst entry for the | |
948 | * default router instead | |
949 | */ | |
950 | dst_release(*dst); | |
951 | memcpy(&fl_gw, fl, sizeof(struct flowi)); | |
952 | memset(&fl_gw.fl6_dst, 0, sizeof(struct in6_addr)); | |
953 | *dst = ip6_route_output(sk, &fl_gw); | |
954 | if ((err = (*dst)->error)) | |
955 | goto out_err_release; | |
956 | } | |
957 | } | |
958 | #endif | |
959 | ||
1da177e4 LT |
960 | return 0; |
961 | ||
962 | out_err_release: | |
ca46f9c8 MC |
963 | if (err == -ENETUNREACH) |
964 | IP6_INC_STATS_BH(NULL, IPSTATS_MIB_OUTNOROUTES); | |
1da177e4 LT |
965 | dst_release(*dst); |
966 | *dst = NULL; | |
967 | return err; | |
968 | } | |
34a0b3cd | 969 | |
497c615a HX |
970 | /** |
971 | * ip6_dst_lookup - perform route lookup on flow | |
972 | * @sk: socket which provides route info | |
973 | * @dst: pointer to dst_entry * for result | |
974 | * @fl: flow to lookup | |
975 | * | |
976 | * This function performs a route lookup on the given flow. | |
977 | * | |
978 | * It returns zero on success, or a standard errno code on error. | |
979 | */ | |
980 | int ip6_dst_lookup(struct sock *sk, struct dst_entry **dst, struct flowi *fl) | |
981 | { | |
982 | *dst = NULL; | |
983 | return ip6_dst_lookup_tail(sk, dst, fl); | |
984 | } | |
3cf3dc6c ACM |
985 | EXPORT_SYMBOL_GPL(ip6_dst_lookup); |
986 | ||
497c615a HX |
987 | /** |
988 | * ip6_sk_dst_lookup - perform socket cached route lookup on flow | |
989 | * @sk: socket which provides the dst cache and route info | |
990 | * @dst: pointer to dst_entry * for result | |
991 | * @fl: flow to lookup | |
992 | * | |
993 | * This function performs a route lookup on the given flow with the | |
994 | * possibility of using the cached route in the socket if it is valid. | |
995 | * It will take the socket dst lock when operating on the dst cache. | |
996 | * As a result, this function can only be used in process context. | |
997 | * | |
998 | * It returns zero on success, or a standard errno code on error. | |
999 | */ | |
1000 | int ip6_sk_dst_lookup(struct sock *sk, struct dst_entry **dst, struct flowi *fl) | |
1001 | { | |
1002 | *dst = NULL; | |
1003 | if (sk) { | |
1004 | *dst = sk_dst_check(sk, inet6_sk(sk)->dst_cookie); | |
1005 | *dst = ip6_sk_dst_check(sk, *dst, fl); | |
1006 | } | |
1007 | ||
1008 | return ip6_dst_lookup_tail(sk, dst, fl); | |
1009 | } | |
1010 | EXPORT_SYMBOL_GPL(ip6_sk_dst_lookup); | |
1011 | ||
34a0b3cd | 1012 | static inline int ip6_ufo_append_data(struct sock *sk, |
e89e9cf5 AR |
1013 | int getfrag(void *from, char *to, int offset, int len, |
1014 | int odd, struct sk_buff *skb), | |
1015 | void *from, int length, int hh_len, int fragheaderlen, | |
1016 | int transhdrlen, int mtu,unsigned int flags) | |
1017 | ||
1018 | { | |
1019 | struct sk_buff *skb; | |
1020 | int err; | |
1021 | ||
1022 | /* There is support for UDP large send offload by network | |
1023 | * device, so create one single skb packet containing complete | |
1024 | * udp datagram | |
1025 | */ | |
1026 | if ((skb = skb_peek_tail(&sk->sk_write_queue)) == NULL) { | |
1027 | skb = sock_alloc_send_skb(sk, | |
1028 | hh_len + fragheaderlen + transhdrlen + 20, | |
1029 | (flags & MSG_DONTWAIT), &err); | |
1030 | if (skb == NULL) | |
1031 | return -ENOMEM; | |
1032 | ||
1033 | /* reserve space for Hardware header */ | |
1034 | skb_reserve(skb, hh_len); | |
1035 | ||
1036 | /* create space for UDP/IP header */ | |
1037 | skb_put(skb,fragheaderlen + transhdrlen); | |
1038 | ||
1039 | /* initialize network header pointer */ | |
c1d2bbe1 | 1040 | skb_reset_network_header(skb); |
e89e9cf5 AR |
1041 | |
1042 | /* initialize protocol header pointer */ | |
b0e380b1 | 1043 | skb->transport_header = skb->network_header + fragheaderlen; |
e89e9cf5 | 1044 | |
84fa7933 | 1045 | skb->ip_summed = CHECKSUM_PARTIAL; |
e89e9cf5 AR |
1046 | skb->csum = 0; |
1047 | sk->sk_sndmsg_off = 0; | |
1048 | } | |
1049 | ||
1050 | err = skb_append_datato_frags(sk,skb, getfrag, from, | |
1051 | (length - transhdrlen)); | |
1052 | if (!err) { | |
1053 | struct frag_hdr fhdr; | |
1054 | ||
1055 | /* specify the length of each IP datagram fragment*/ | |
1ab1457c | 1056 | skb_shinfo(skb)->gso_size = mtu - fragheaderlen - |
7967168c | 1057 | sizeof(struct frag_hdr); |
f83ef8c0 | 1058 | skb_shinfo(skb)->gso_type = SKB_GSO_UDP; |
e89e9cf5 AR |
1059 | ipv6_select_ident(skb, &fhdr); |
1060 | skb_shinfo(skb)->ip6_frag_id = fhdr.identification; | |
1061 | __skb_queue_tail(&sk->sk_write_queue, skb); | |
1062 | ||
1063 | return 0; | |
1064 | } | |
1065 | /* There is not enough support do UPD LSO, | |
1066 | * so follow normal path | |
1067 | */ | |
1068 | kfree_skb(skb); | |
1069 | ||
1070 | return err; | |
1071 | } | |
1da177e4 | 1072 | |
41a1f8ea YH |
1073 | int ip6_append_data(struct sock *sk, int getfrag(void *from, char *to, |
1074 | int offset, int len, int odd, struct sk_buff *skb), | |
1075 | void *from, int length, int transhdrlen, | |
1076 | int hlimit, int tclass, struct ipv6_txoptions *opt, struct flowi *fl, | |
1077 | struct rt6_info *rt, unsigned int flags) | |
1da177e4 LT |
1078 | { |
1079 | struct inet_sock *inet = inet_sk(sk); | |
1080 | struct ipv6_pinfo *np = inet6_sk(sk); | |
1081 | struct sk_buff *skb; | |
1082 | unsigned int maxfraglen, fragheaderlen; | |
1083 | int exthdrlen; | |
1084 | int hh_len; | |
1085 | int mtu; | |
1086 | int copy; | |
1087 | int err; | |
1088 | int offset = 0; | |
1089 | int csummode = CHECKSUM_NONE; | |
1090 | ||
1091 | if (flags&MSG_PROBE) | |
1092 | return 0; | |
1093 | if (skb_queue_empty(&sk->sk_write_queue)) { | |
1094 | /* | |
1095 | * setup for corking | |
1096 | */ | |
1097 | if (opt) { | |
1098 | if (np->cork.opt == NULL) { | |
1099 | np->cork.opt = kmalloc(opt->tot_len, | |
1100 | sk->sk_allocation); | |
1101 | if (unlikely(np->cork.opt == NULL)) | |
1102 | return -ENOBUFS; | |
1103 | } else if (np->cork.opt->tot_len < opt->tot_len) { | |
1104 | printk(KERN_DEBUG "ip6_append_data: invalid option length\n"); | |
1105 | return -EINVAL; | |
1106 | } | |
1107 | memcpy(np->cork.opt, opt, opt->tot_len); | |
1108 | inet->cork.flags |= IPCORK_OPT; | |
1109 | /* need source address above miyazawa*/ | |
1110 | } | |
1111 | dst_hold(&rt->u.dst); | |
1112 | np->cork.rt = rt; | |
1113 | inet->cork.fl = *fl; | |
1114 | np->cork.hop_limit = hlimit; | |
41a1f8ea | 1115 | np->cork.tclass = tclass; |
628a5c56 JH |
1116 | mtu = np->pmtudisc == IPV6_PMTUDISC_PROBE ? |
1117 | rt->u.dst.dev->mtu : dst_mtu(rt->u.dst.path); | |
c7503609 | 1118 | if (np->frag_size < mtu) { |
d91675f9 YH |
1119 | if (np->frag_size) |
1120 | mtu = np->frag_size; | |
1121 | } | |
1122 | inet->cork.fragsize = mtu; | |
1da177e4 LT |
1123 | if (dst_allfrag(rt->u.dst.path)) |
1124 | inet->cork.flags |= IPCORK_ALLFRAG; | |
1125 | inet->cork.length = 0; | |
1126 | sk->sk_sndmsg_page = NULL; | |
1127 | sk->sk_sndmsg_off = 0; | |
01488942 | 1128 | exthdrlen = rt->u.dst.header_len + (opt ? opt->opt_flen : 0) - |
a1b05140 | 1129 | rt->rt6i_nfheader_len; |
1da177e4 LT |
1130 | length += exthdrlen; |
1131 | transhdrlen += exthdrlen; | |
1132 | } else { | |
1133 | rt = np->cork.rt; | |
1134 | fl = &inet->cork.fl; | |
1135 | if (inet->cork.flags & IPCORK_OPT) | |
1136 | opt = np->cork.opt; | |
1137 | transhdrlen = 0; | |
1138 | exthdrlen = 0; | |
1139 | mtu = inet->cork.fragsize; | |
1140 | } | |
1141 | ||
1142 | hh_len = LL_RESERVED_SPACE(rt->u.dst.dev); | |
1143 | ||
a1b05140 | 1144 | fragheaderlen = sizeof(struct ipv6hdr) + rt->rt6i_nfheader_len + |
b4ce9277 | 1145 | (opt ? opt->opt_nflen : 0); |
1da177e4 LT |
1146 | maxfraglen = ((mtu - fragheaderlen) & ~7) + fragheaderlen - sizeof(struct frag_hdr); |
1147 | ||
1148 | if (mtu <= sizeof(struct ipv6hdr) + IPV6_MAXPLEN) { | |
1149 | if (inet->cork.length + length > sizeof(struct ipv6hdr) + IPV6_MAXPLEN - fragheaderlen) { | |
1150 | ipv6_local_error(sk, EMSGSIZE, fl, mtu-exthdrlen); | |
1151 | return -EMSGSIZE; | |
1152 | } | |
1153 | } | |
1154 | ||
1155 | /* | |
1156 | * Let's try using as much space as possible. | |
1157 | * Use MTU if total length of the message fits into the MTU. | |
1158 | * Otherwise, we need to reserve fragment header and | |
1159 | * fragment alignment (= 8-15 octects, in total). | |
1160 | * | |
1161 | * Note that we may need to "move" the data from the tail of | |
1ab1457c | 1162 | * of the buffer to the new fragment when we split |
1da177e4 LT |
1163 | * the message. |
1164 | * | |
1ab1457c | 1165 | * FIXME: It may be fragmented into multiple chunks |
1da177e4 LT |
1166 | * at once if non-fragmentable extension headers |
1167 | * are too large. | |
1ab1457c | 1168 | * --yoshfuji |
1da177e4 LT |
1169 | */ |
1170 | ||
1171 | inet->cork.length += length; | |
e89e9cf5 AR |
1172 | if (((length > mtu) && (sk->sk_protocol == IPPROTO_UDP)) && |
1173 | (rt->u.dst.dev->features & NETIF_F_UFO)) { | |
1174 | ||
baa829d8 PM |
1175 | err = ip6_ufo_append_data(sk, getfrag, from, length, hh_len, |
1176 | fragheaderlen, transhdrlen, mtu, | |
1177 | flags); | |
1178 | if (err) | |
e89e9cf5 | 1179 | goto error; |
e89e9cf5 AR |
1180 | return 0; |
1181 | } | |
1da177e4 LT |
1182 | |
1183 | if ((skb = skb_peek_tail(&sk->sk_write_queue)) == NULL) | |
1184 | goto alloc_new_skb; | |
1185 | ||
1186 | while (length > 0) { | |
1187 | /* Check if the remaining data fits into current packet. */ | |
1188 | copy = (inet->cork.length <= mtu && !(inet->cork.flags & IPCORK_ALLFRAG) ? mtu : maxfraglen) - skb->len; | |
1189 | if (copy < length) | |
1190 | copy = maxfraglen - skb->len; | |
1191 | ||
1192 | if (copy <= 0) { | |
1193 | char *data; | |
1194 | unsigned int datalen; | |
1195 | unsigned int fraglen; | |
1196 | unsigned int fraggap; | |
1197 | unsigned int alloclen; | |
1198 | struct sk_buff *skb_prev; | |
1199 | alloc_new_skb: | |
1200 | skb_prev = skb; | |
1201 | ||
1202 | /* There's no room in the current skb */ | |
1203 | if (skb_prev) | |
1204 | fraggap = skb_prev->len - maxfraglen; | |
1205 | else | |
1206 | fraggap = 0; | |
1207 | ||
1208 | /* | |
1209 | * If remaining data exceeds the mtu, | |
1210 | * we know we need more fragment(s). | |
1211 | */ | |
1212 | datalen = length + fraggap; | |
1213 | if (datalen > (inet->cork.length <= mtu && !(inet->cork.flags & IPCORK_ALLFRAG) ? mtu : maxfraglen) - fragheaderlen) | |
1214 | datalen = maxfraglen - fragheaderlen; | |
1215 | ||
1216 | fraglen = datalen + fragheaderlen; | |
1217 | if ((flags & MSG_MORE) && | |
1218 | !(rt->u.dst.dev->features&NETIF_F_SG)) | |
1219 | alloclen = mtu; | |
1220 | else | |
1221 | alloclen = datalen + fragheaderlen; | |
1222 | ||
1223 | /* | |
1224 | * The last fragment gets additional space at tail. | |
1225 | * Note: we overallocate on fragments with MSG_MODE | |
1226 | * because we have no idea if we're the last one. | |
1227 | */ | |
1228 | if (datalen == length + fraggap) | |
1229 | alloclen += rt->u.dst.trailer_len; | |
1230 | ||
1231 | /* | |
1232 | * We just reserve space for fragment header. | |
1ab1457c | 1233 | * Note: this may be overallocation if the message |
1da177e4 LT |
1234 | * (without MSG_MORE) fits into the MTU. |
1235 | */ | |
1236 | alloclen += sizeof(struct frag_hdr); | |
1237 | ||
1238 | if (transhdrlen) { | |
1239 | skb = sock_alloc_send_skb(sk, | |
1240 | alloclen + hh_len, | |
1241 | (flags & MSG_DONTWAIT), &err); | |
1242 | } else { | |
1243 | skb = NULL; | |
1244 | if (atomic_read(&sk->sk_wmem_alloc) <= | |
1245 | 2 * sk->sk_sndbuf) | |
1246 | skb = sock_wmalloc(sk, | |
1247 | alloclen + hh_len, 1, | |
1248 | sk->sk_allocation); | |
1249 | if (unlikely(skb == NULL)) | |
1250 | err = -ENOBUFS; | |
1251 | } | |
1252 | if (skb == NULL) | |
1253 | goto error; | |
1254 | /* | |
1255 | * Fill in the control structures | |
1256 | */ | |
1257 | skb->ip_summed = csummode; | |
1258 | skb->csum = 0; | |
1259 | /* reserve for fragmentation */ | |
1260 | skb_reserve(skb, hh_len+sizeof(struct frag_hdr)); | |
1261 | ||
1262 | /* | |
1263 | * Find where to start putting bytes | |
1264 | */ | |
1265 | data = skb_put(skb, fraglen); | |
c14d2450 | 1266 | skb_set_network_header(skb, exthdrlen); |
1da177e4 | 1267 | data += fragheaderlen; |
b0e380b1 ACM |
1268 | skb->transport_header = (skb->network_header + |
1269 | fragheaderlen); | |
1da177e4 LT |
1270 | if (fraggap) { |
1271 | skb->csum = skb_copy_and_csum_bits( | |
1272 | skb_prev, maxfraglen, | |
1273 | data + transhdrlen, fraggap, 0); | |
1274 | skb_prev->csum = csum_sub(skb_prev->csum, | |
1275 | skb->csum); | |
1276 | data += fraggap; | |
e9fa4f7b | 1277 | pskb_trim_unique(skb_prev, maxfraglen); |
1da177e4 LT |
1278 | } |
1279 | copy = datalen - transhdrlen - fraggap; | |
1280 | if (copy < 0) { | |
1281 | err = -EINVAL; | |
1282 | kfree_skb(skb); | |
1283 | goto error; | |
1284 | } else if (copy > 0 && getfrag(from, data + transhdrlen, offset, copy, fraggap, skb) < 0) { | |
1285 | err = -EFAULT; | |
1286 | kfree_skb(skb); | |
1287 | goto error; | |
1288 | } | |
1289 | ||
1290 | offset += copy; | |
1291 | length -= datalen - fraggap; | |
1292 | transhdrlen = 0; | |
1293 | exthdrlen = 0; | |
1294 | csummode = CHECKSUM_NONE; | |
1295 | ||
1296 | /* | |
1297 | * Put the packet on the pending queue | |
1298 | */ | |
1299 | __skb_queue_tail(&sk->sk_write_queue, skb); | |
1300 | continue; | |
1301 | } | |
1302 | ||
1303 | if (copy > length) | |
1304 | copy = length; | |
1305 | ||
1306 | if (!(rt->u.dst.dev->features&NETIF_F_SG)) { | |
1307 | unsigned int off; | |
1308 | ||
1309 | off = skb->len; | |
1310 | if (getfrag(from, skb_put(skb, copy), | |
1311 | offset, copy, off, skb) < 0) { | |
1312 | __skb_trim(skb, off); | |
1313 | err = -EFAULT; | |
1314 | goto error; | |
1315 | } | |
1316 | } else { | |
1317 | int i = skb_shinfo(skb)->nr_frags; | |
1318 | skb_frag_t *frag = &skb_shinfo(skb)->frags[i-1]; | |
1319 | struct page *page = sk->sk_sndmsg_page; | |
1320 | int off = sk->sk_sndmsg_off; | |
1321 | unsigned int left; | |
1322 | ||
1323 | if (page && (left = PAGE_SIZE - off) > 0) { | |
1324 | if (copy >= left) | |
1325 | copy = left; | |
1326 | if (page != frag->page) { | |
1327 | if (i == MAX_SKB_FRAGS) { | |
1328 | err = -EMSGSIZE; | |
1329 | goto error; | |
1330 | } | |
1331 | get_page(page); | |
1332 | skb_fill_page_desc(skb, i, page, sk->sk_sndmsg_off, 0); | |
1333 | frag = &skb_shinfo(skb)->frags[i]; | |
1334 | } | |
1335 | } else if(i < MAX_SKB_FRAGS) { | |
1336 | if (copy > PAGE_SIZE) | |
1337 | copy = PAGE_SIZE; | |
1338 | page = alloc_pages(sk->sk_allocation, 0); | |
1339 | if (page == NULL) { | |
1340 | err = -ENOMEM; | |
1341 | goto error; | |
1342 | } | |
1343 | sk->sk_sndmsg_page = page; | |
1344 | sk->sk_sndmsg_off = 0; | |
1345 | ||
1346 | skb_fill_page_desc(skb, i, page, 0, 0); | |
1347 | frag = &skb_shinfo(skb)->frags[i]; | |
1da177e4 LT |
1348 | } else { |
1349 | err = -EMSGSIZE; | |
1350 | goto error; | |
1351 | } | |
1352 | if (getfrag(from, page_address(frag->page)+frag->page_offset+frag->size, offset, copy, skb->len, skb) < 0) { | |
1353 | err = -EFAULT; | |
1354 | goto error; | |
1355 | } | |
1356 | sk->sk_sndmsg_off += copy; | |
1357 | frag->size += copy; | |
1358 | skb->len += copy; | |
1359 | skb->data_len += copy; | |
f945fa7a HX |
1360 | skb->truesize += copy; |
1361 | atomic_add(copy, &sk->sk_wmem_alloc); | |
1da177e4 LT |
1362 | } |
1363 | offset += copy; | |
1364 | length -= copy; | |
1365 | } | |
1366 | return 0; | |
1367 | error: | |
1368 | inet->cork.length -= length; | |
a11d206d | 1369 | IP6_INC_STATS(rt->rt6i_idev, IPSTATS_MIB_OUTDISCARDS); |
1da177e4 LT |
1370 | return err; |
1371 | } | |
1372 | ||
bf138862 PE |
1373 | static void ip6_cork_release(struct inet_sock *inet, struct ipv6_pinfo *np) |
1374 | { | |
1375 | inet->cork.flags &= ~IPCORK_OPT; | |
1376 | kfree(np->cork.opt); | |
1377 | np->cork.opt = NULL; | |
1378 | if (np->cork.rt) { | |
1379 | dst_release(&np->cork.rt->u.dst); | |
1380 | np->cork.rt = NULL; | |
1381 | inet->cork.flags &= ~IPCORK_ALLFRAG; | |
1382 | } | |
1383 | memset(&inet->cork.fl, 0, sizeof(inet->cork.fl)); | |
1384 | } | |
1385 | ||
1da177e4 LT |
1386 | int ip6_push_pending_frames(struct sock *sk) |
1387 | { | |
1388 | struct sk_buff *skb, *tmp_skb; | |
1389 | struct sk_buff **tail_skb; | |
1390 | struct in6_addr final_dst_buf, *final_dst = &final_dst_buf; | |
1391 | struct inet_sock *inet = inet_sk(sk); | |
1392 | struct ipv6_pinfo *np = inet6_sk(sk); | |
1393 | struct ipv6hdr *hdr; | |
1394 | struct ipv6_txoptions *opt = np->cork.opt; | |
1395 | struct rt6_info *rt = np->cork.rt; | |
1396 | struct flowi *fl = &inet->cork.fl; | |
1397 | unsigned char proto = fl->proto; | |
1398 | int err = 0; | |
1399 | ||
1400 | if ((skb = __skb_dequeue(&sk->sk_write_queue)) == NULL) | |
1401 | goto out; | |
1402 | tail_skb = &(skb_shinfo(skb)->frag_list); | |
1403 | ||
1404 | /* move skb->data to ip header from ext header */ | |
d56f90a7 | 1405 | if (skb->data < skb_network_header(skb)) |
bbe735e4 | 1406 | __skb_pull(skb, skb_network_offset(skb)); |
1da177e4 | 1407 | while ((tmp_skb = __skb_dequeue(&sk->sk_write_queue)) != NULL) { |
cfe1fc77 | 1408 | __skb_pull(tmp_skb, skb_network_header_len(skb)); |
1da177e4 LT |
1409 | *tail_skb = tmp_skb; |
1410 | tail_skb = &(tmp_skb->next); | |
1411 | skb->len += tmp_skb->len; | |
1412 | skb->data_len += tmp_skb->len; | |
1da177e4 LT |
1413 | skb->truesize += tmp_skb->truesize; |
1414 | __sock_put(tmp_skb->sk); | |
1415 | tmp_skb->destructor = NULL; | |
1416 | tmp_skb->sk = NULL; | |
1da177e4 LT |
1417 | } |
1418 | ||
1419 | ipv6_addr_copy(final_dst, &fl->fl6_dst); | |
cfe1fc77 | 1420 | __skb_pull(skb, skb_network_header_len(skb)); |
1da177e4 LT |
1421 | if (opt && opt->opt_flen) |
1422 | ipv6_push_frag_opts(skb, opt, &proto); | |
1423 | if (opt && opt->opt_nflen) | |
1424 | ipv6_push_nfrag_opts(skb, opt, &proto, &final_dst); | |
1425 | ||
e2d1bca7 ACM |
1426 | skb_push(skb, sizeof(struct ipv6hdr)); |
1427 | skb_reset_network_header(skb); | |
0660e03f | 1428 | hdr = ipv6_hdr(skb); |
1ab1457c | 1429 | |
90bcaf7b | 1430 | *(__be32*)hdr = fl->fl6_flowlabel | |
41a1f8ea | 1431 | htonl(0x60000000 | ((int)np->cork.tclass << 20)); |
1da177e4 | 1432 | |
1da177e4 LT |
1433 | hdr->hop_limit = np->cork.hop_limit; |
1434 | hdr->nexthdr = proto; | |
1435 | ipv6_addr_copy(&hdr->saddr, &fl->fl6_src); | |
1436 | ipv6_addr_copy(&hdr->daddr, final_dst); | |
1437 | ||
a2c2064f PM |
1438 | skb->priority = sk->sk_priority; |
1439 | ||
1da177e4 | 1440 | skb->dst = dst_clone(&rt->u.dst); |
a11d206d | 1441 | IP6_INC_STATS(rt->rt6i_idev, IPSTATS_MIB_OUTREQUESTS); |
14878f75 DS |
1442 | if (proto == IPPROTO_ICMPV6) { |
1443 | struct inet6_dev *idev = ip6_dst_idev(skb->dst); | |
1444 | ||
1445 | ICMP6MSGOUT_INC_STATS_BH(idev, icmp6_hdr(skb)->icmp6_type); | |
1446 | ICMP6_INC_STATS_BH(idev, ICMP6_MIB_OUTMSGS); | |
1447 | } | |
1448 | ||
ef76bc23 | 1449 | err = ip6_local_out(skb); |
1da177e4 LT |
1450 | if (err) { |
1451 | if (err > 0) | |
3320da89 | 1452 | err = np->recverr ? net_xmit_errno(err) : 0; |
1da177e4 LT |
1453 | if (err) |
1454 | goto error; | |
1455 | } | |
1456 | ||
1457 | out: | |
bf138862 | 1458 | ip6_cork_release(inet, np); |
1da177e4 LT |
1459 | return err; |
1460 | error: | |
1461 | goto out; | |
1462 | } | |
1463 | ||
1464 | void ip6_flush_pending_frames(struct sock *sk) | |
1465 | { | |
1da177e4 LT |
1466 | struct sk_buff *skb; |
1467 | ||
1468 | while ((skb = __skb_dequeue_tail(&sk->sk_write_queue)) != NULL) { | |
e1f52208 YH |
1469 | if (skb->dst) |
1470 | IP6_INC_STATS(ip6_dst_idev(skb->dst), | |
1471 | IPSTATS_MIB_OUTDISCARDS); | |
1da177e4 LT |
1472 | kfree_skb(skb); |
1473 | } | |
1474 | ||
bf138862 | 1475 | ip6_cork_release(inet_sk(sk), inet6_sk(sk)); |
1da177e4 | 1476 | } |