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[PATCH] libertas: bump version to 322.p1
[linux-2.6.git] / net / ipv6 / exthdrs.c
blobc82d4d49f71f1aff4eada6daaa69f8718bbbe019
1 /*
2 * Extension Header handling for IPv6
3 * Linux INET6 implementation
4 *
5 * Authors:
6 * Pedro Roque <roque@di.fc.ul.pt>
7 * Andi Kleen <ak@muc.de>
8 * Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
9 *
10 * $Id: exthdrs.c,v 1.13 2001/06/19 15:58:56 davem Exp $
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
18 /* Changes:
19 * yoshfuji : ensure not to overrun while parsing
20 * tlv options.
21 * Mitsuru KANDA @USAGI and: Remove ipv6_parse_exthdrs().
22 * YOSHIFUJI Hideaki @USAGI Register inbound extension header
23 * handlers as inet6_protocol{}.
24 */
25
26 #include <linux/errno.h>
27 #include <linux/types.h>
28 #include <linux/socket.h>
29 #include <linux/sockios.h>
30 #include <linux/net.h>
31 #include <linux/netdevice.h>
32 #include <linux/in6.h>
33 #include <linux/icmpv6.h>
34
35 #include <net/sock.h>
36 #include <net/snmp.h>
37
38 #include <net/ipv6.h>
39 #include <net/protocol.h>
40 #include <net/transp_v6.h>
41 #include <net/rawv6.h>
42 #include <net/ndisc.h>
43 #include <net/ip6_route.h>
44 #include <net/addrconf.h>
45 #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
46 #include <net/xfrm.h>
47 #endif
48
49 #include <asm/uaccess.h>
50
51 int ipv6_find_tlv(struct sk_buff *skb, int offset, int type)
52 {
53 const unsigned char *nh = skb_network_header(skb);
54 int packet_len = skb->tail - skb->network_header;
55 struct ipv6_opt_hdr *hdr;
56 int len;
57
58 if (offset + 2 > packet_len)
59 goto bad;
60 hdr = (struct ipv6_opt_hdr *)(nh + offset);
61 len = ((hdr->hdrlen + 1) << 3);
62
63 if (offset + len > packet_len)
64 goto bad;
65
66 offset += 2;
67 len -= 2;
68
69 while (len > 0) {
70 int opttype = nh[offset];
71 int optlen;
72
73 if (opttype == type)
74 return offset;
75
76 switch (opttype) {
77 case IPV6_TLV_PAD0:
78 optlen = 1;
79 break;
80 default:
81 optlen = nh[offset + 1] + 2;
82 if (optlen > len)
83 goto bad;
84 break;
85 }
86 offset += optlen;
87 len -= optlen;
88 }
89 /* not_found */
90 bad:
91 return -1;
92 }
93 EXPORT_SYMBOL_GPL(ipv6_find_tlv);
94
95 /*
96 * Parsing tlv encoded headers.
97 *
98 * Parsing function "func" returns 1, if parsing succeed
99 * and 0, if it failed.
100 * It MUST NOT touch skb->h.
101 */
102
103 struct tlvtype_proc {
104 int type;
105 int (*func)(struct sk_buff **skbp, int offset);
106 };
107
108 /*********************
109 Generic functions
110 *********************/
111
112 /* An unknown option is detected, decide what to do */
113
114 static int ip6_tlvopt_unknown(struct sk_buff **skbp, int optoff)
115 {
116 struct sk_buff *skb = *skbp;
117
118 switch ((skb_network_header(skb)[optoff] & 0xC0) >> 6) {
119 case 0: /* ignore */
120 return 1;
121
122 case 1: /* drop packet */
123 break;
124
125 case 3: /* Send ICMP if not a multicast address and drop packet */
126 /* Actually, it is redundant check. icmp_send
127 will recheck in any case.
128 */
129 if (ipv6_addr_is_multicast(&ipv6_hdr(skb)->daddr))
130 break;
131 case 2: /* send ICMP PARM PROB regardless and drop packet */
132 icmpv6_param_prob(skb, ICMPV6_UNK_OPTION, optoff);
133 return 0;
134 }
135
136 kfree_skb(skb);
137 return 0;
138 }
139
140 /* Parse tlv encoded option header (hop-by-hop or destination) */
141
142 static int ip6_parse_tlv(struct tlvtype_proc *procs, struct sk_buff **skbp)
143 {
144 struct sk_buff *skb = *skbp;
145 struct tlvtype_proc *curr;
146 const unsigned char *nh = skb_network_header(skb);
147 int off = skb_network_header_len(skb);
148 int len = (skb_transport_header(skb)[1] + 1) << 3;
149
150 if (skb_transport_offset(skb) + len > skb_headlen(skb))
151 goto bad;
152
153 off += 2;
154 len -= 2;
155
156 while (len > 0) {
157 int optlen = nh[off + 1] + 2;
158
159 switch (nh[off]) {
160 case IPV6_TLV_PAD0:
161 optlen = 1;
162 break;
163
164 case IPV6_TLV_PADN:
165 break;
166
167 default: /* Other TLV code so scan list */
168 if (optlen > len)
169 goto bad;
170 for (curr=procs; curr->type >= 0; curr++) {
171 if (curr->type == nh[off]) {
172 /* type specific length/alignment
173 checks will be performed in the
174 func(). */
175 if (curr->func(skbp, off) == 0)
176 return 0;
177 break;
178 }
179 }
180 if (curr->type < 0) {
181 if (ip6_tlvopt_unknown(skbp, off) == 0)
182 return 0;
183 }
184 break;
185 }
186 off += optlen;
187 len -= optlen;
188 }
189 if (len == 0)
190 return 1;
191 bad:
192 kfree_skb(skb);
193 return 0;
194 }
195
196 /*****************************
197 Destination options header.
198 *****************************/
199
200 #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
201 static int ipv6_dest_hao(struct sk_buff **skbp, int optoff)
202 {
203 struct sk_buff *skb = *skbp;
204 struct ipv6_destopt_hao *hao;
205 struct inet6_skb_parm *opt = IP6CB(skb);
206 struct ipv6hdr *ipv6h = ipv6_hdr(skb);
207 struct in6_addr tmp_addr;
208 int ret;
209
210 if (opt->dsthao) {
211 LIMIT_NETDEBUG(KERN_DEBUG "hao duplicated\n");
212 goto discard;
213 }
214 opt->dsthao = opt->dst1;
215 opt->dst1 = 0;
216
217 hao = (struct ipv6_destopt_hao *)(skb_network_header(skb) + optoff);
218
219 if (hao->length != 16) {
220 LIMIT_NETDEBUG(
221 KERN_DEBUG "hao invalid option length = %d\n", hao->length);
222 goto discard;
223 }
224
225 if (!(ipv6_addr_type(&hao->addr) & IPV6_ADDR_UNICAST)) {
226 LIMIT_NETDEBUG(
227 KERN_DEBUG "hao is not an unicast addr: " NIP6_FMT "\n", NIP6(hao->addr));
228 goto discard;
229 }
230
231 ret = xfrm6_input_addr(skb, (xfrm_address_t *)&ipv6h->daddr,
232 (xfrm_address_t *)&hao->addr, IPPROTO_DSTOPTS);
233 if (unlikely(ret < 0))
234 goto discard;
235
236 if (skb_cloned(skb)) {
237 struct sk_buff *skb2 = skb_copy(skb, GFP_ATOMIC);
238 struct inet6_skb_parm *opt2;
239
240 if (skb2 == NULL)
241 goto discard;
242
243 opt2 = IP6CB(skb2);
244 memcpy(opt2, opt, sizeof(*opt2));
245
246 kfree_skb(skb);
247
248 /* update all variable using below by copied skbuff */
249 *skbp = skb = skb2;
250 hao = (struct ipv6_destopt_hao *)(skb_network_header(skb2) +
251 optoff);
252 ipv6h = ipv6_hdr(skb2);
253 }
254
255 if (skb->ip_summed == CHECKSUM_COMPLETE)
256 skb->ip_summed = CHECKSUM_NONE;
257
258 ipv6_addr_copy(&tmp_addr, &ipv6h->saddr);
259 ipv6_addr_copy(&ipv6h->saddr, &hao->addr);
260 ipv6_addr_copy(&hao->addr, &tmp_addr);
261
262 if (skb->tstamp.tv64 == 0)
263 __net_timestamp(skb);
264
265 return 1;
266
267 discard:
268 kfree_skb(skb);
269 return 0;
270 }
271 #endif
272
273 static struct tlvtype_proc tlvprocdestopt_lst[] = {
274 #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
275 {
276 .type = IPV6_TLV_HAO,
277 .func = ipv6_dest_hao,
278 },
279 #endif
280 {-1, NULL}
281 };
282
283 static int ipv6_destopt_rcv(struct sk_buff **skbp)
284 {
285 struct sk_buff *skb = *skbp;
286 struct inet6_skb_parm *opt = IP6CB(skb);
287 #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
288 __u16 dstbuf;
289 #endif
290 struct dst_entry *dst;
291
292 if (!pskb_may_pull(skb, skb_transport_offset(skb) + 8) ||
293 !pskb_may_pull(skb, (skb_transport_offset(skb) +
294 ((skb_transport_header(skb)[1] + 1) << 3)))) {
295 IP6_INC_STATS_BH(ip6_dst_idev(skb->dst),
296 IPSTATS_MIB_INHDRERRORS);
297 kfree_skb(skb);
298 return -1;
299 }
300
301 opt->lastopt = opt->dst1 = skb_network_header_len(skb);
302 #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
303 dstbuf = opt->dst1;
304 #endif
305
306 dst = dst_clone(skb->dst);
307 if (ip6_parse_tlv(tlvprocdestopt_lst, skbp)) {
308 dst_release(dst);
309 skb = *skbp;
310 skb->transport_header += (skb_transport_header(skb)[1] + 1) << 3;
311 opt = IP6CB(skb);
312 #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
313 opt->nhoff = dstbuf;
314 #else
315 opt->nhoff = opt->dst1;
316 #endif
317 return 1;
318 }
319
320 IP6_INC_STATS_BH(ip6_dst_idev(dst), IPSTATS_MIB_INHDRERRORS);
321 dst_release(dst);
322 return -1;
323 }
324
325 static struct inet6_protocol destopt_protocol = {
326 .handler = ipv6_destopt_rcv,
327 .flags = INET6_PROTO_NOPOLICY | INET6_PROTO_GSO_EXTHDR,
328 };
329
330 void __init ipv6_destopt_init(void)
331 {
332 if (inet6_add_protocol(&destopt_protocol, IPPROTO_DSTOPTS) < 0)
333 printk(KERN_ERR "ipv6_destopt_init: Could not register protocol\n");
334 }
335
336 /********************************
337 NONE header. No data in packet.
338 ********************************/
339
340 static int ipv6_nodata_rcv(struct sk_buff **skbp)
341 {
342 struct sk_buff *skb = *skbp;
343
344 kfree_skb(skb);
345 return 0;
346 }
347
348 static struct inet6_protocol nodata_protocol = {
349 .handler = ipv6_nodata_rcv,
350 .flags = INET6_PROTO_NOPOLICY,
351 };
352
353 void __init ipv6_nodata_init(void)
354 {
355 if (inet6_add_protocol(&nodata_protocol, IPPROTO_NONE) < 0)
356 printk(KERN_ERR "ipv6_nodata_init: Could not register protocol\n");
357 }
358
359 /********************************
360 Routing header.
361 ********************************/
362
363 static int ipv6_rthdr_rcv(struct sk_buff **skbp)
364 {
365 struct sk_buff *skb = *skbp;
366 struct inet6_skb_parm *opt = IP6CB(skb);
367 struct in6_addr *addr = NULL;
368 struct in6_addr daddr;
369 struct inet6_dev *idev;
370 int n, i;
371 struct ipv6_rt_hdr *hdr;
372 struct rt0_hdr *rthdr;
373 int accept_source_route = ipv6_devconf.accept_source_route;
374
375 idev = in6_dev_get(skb->dev);
376 if (idev) {
377 if (accept_source_route > idev->cnf.accept_source_route)
378 accept_source_route = idev->cnf.accept_source_route;
379 in6_dev_put(idev);
380 }
381
382 if (!pskb_may_pull(skb, skb_transport_offset(skb) + 8) ||
383 !pskb_may_pull(skb, (skb_transport_offset(skb) +
384 ((skb_transport_header(skb)[1] + 1) << 3)))) {
385 IP6_INC_STATS_BH(ip6_dst_idev(skb->dst),
386 IPSTATS_MIB_INHDRERRORS);
387 kfree_skb(skb);
388 return -1;
389 }
390
391 hdr = (struct ipv6_rt_hdr *)skb_transport_header(skb);
392
393 if (ipv6_addr_is_multicast(&ipv6_hdr(skb)->daddr) ||
394 skb->pkt_type != PACKET_HOST) {
395 IP6_INC_STATS_BH(ip6_dst_idev(skb->dst),
396 IPSTATS_MIB_INADDRERRORS);
397 kfree_skb(skb);
398 return -1;
399 }
400
401 looped_back:
402 if (hdr->segments_left == 0) {
403 switch (hdr->type) {
404 #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
405 case IPV6_SRCRT_TYPE_2:
406 /* Silently discard type 2 header unless it was
407 * processed by own
408 */
409 if (!addr) {
410 IP6_INC_STATS_BH(ip6_dst_idev(skb->dst),
411 IPSTATS_MIB_INADDRERRORS);
412 kfree_skb(skb);
413 return -1;
414 }
415 break;
416 #endif
417 default:
418 break;
419 }
420
421 opt->lastopt = opt->srcrt = skb_network_header_len(skb);
422 skb->transport_header += (hdr->hdrlen + 1) << 3;
423 opt->dst0 = opt->dst1;
424 opt->dst1 = 0;
425 opt->nhoff = (&hdr->nexthdr) - skb_network_header(skb);
426 return 1;
427 }
428
429 switch (hdr->type) {
430 #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
431 case IPV6_SRCRT_TYPE_2:
432 if (accept_source_route < 0)
433 goto unknown_rh;
434 /* Silently discard invalid RTH type 2 */
435 if (hdr->hdrlen != 2 || hdr->segments_left != 1) {
436 IP6_INC_STATS_BH(ip6_dst_idev(skb->dst),
437 IPSTATS_MIB_INHDRERRORS);
438 kfree_skb(skb);
439 return -1;
440 }
441 break;
442 #endif
443 default:
444 goto unknown_rh;
445 }
446
447 /*
448 * This is the routing header forwarding algorithm from
449 * RFC 2460, page 16.
450 */
451
452 n = hdr->hdrlen >> 1;
453
454 if (hdr->segments_left > n) {
455 IP6_INC_STATS_BH(ip6_dst_idev(skb->dst),
456 IPSTATS_MIB_INHDRERRORS);
457 icmpv6_param_prob(skb, ICMPV6_HDR_FIELD,
458 ((&hdr->segments_left) -
459 skb_network_header(skb)));
460 return -1;
461 }
462
463 /* We are about to mangle packet header. Be careful!
464 Do not damage packets queued somewhere.
465 */
466 if (skb_cloned(skb)) {
467 struct sk_buff *skb2 = skb_copy(skb, GFP_ATOMIC);
468 /* the copy is a forwarded packet */
469 if (skb2 == NULL) {
470 IP6_INC_STATS_BH(ip6_dst_idev(skb->dst),
471 IPSTATS_MIB_OUTDISCARDS);
472 kfree_skb(skb);
473 return -1;
474 }
475 kfree_skb(skb);
476 *skbp = skb = skb2;
477 opt = IP6CB(skb2);
478 hdr = (struct ipv6_rt_hdr *)skb_transport_header(skb2);
479 }
480
481 if (skb->ip_summed == CHECKSUM_COMPLETE)
482 skb->ip_summed = CHECKSUM_NONE;
483
484 i = n - --hdr->segments_left;
485
486 rthdr = (struct rt0_hdr *) hdr;
487 addr = rthdr->addr;
488 addr += i - 1;
489
490 switch (hdr->type) {
491 #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
492 case IPV6_SRCRT_TYPE_2:
493 if (xfrm6_input_addr(skb, (xfrm_address_t *)addr,
494 (xfrm_address_t *)&ipv6_hdr(skb)->saddr,
495 IPPROTO_ROUTING) < 0) {
496 IP6_INC_STATS_BH(ip6_dst_idev(skb->dst),
497 IPSTATS_MIB_INADDRERRORS);
498 kfree_skb(skb);
499 return -1;
500 }
501 if (!ipv6_chk_home_addr(addr)) {
502 IP6_INC_STATS_BH(ip6_dst_idev(skb->dst),
503 IPSTATS_MIB_INADDRERRORS);
504 kfree_skb(skb);
505 return -1;
506 }
507 break;
508 #endif
509 default:
510 break;
511 }
512
513 if (ipv6_addr_is_multicast(addr)) {
514 IP6_INC_STATS_BH(ip6_dst_idev(skb->dst),
515 IPSTATS_MIB_INADDRERRORS);
516 kfree_skb(skb);
517 return -1;
518 }
519
520 ipv6_addr_copy(&daddr, addr);
521 ipv6_addr_copy(addr, &ipv6_hdr(skb)->daddr);
522 ipv6_addr_copy(&ipv6_hdr(skb)->daddr, &daddr);
523
524 dst_release(xchg(&skb->dst, NULL));
525 ip6_route_input(skb);
526 if (skb->dst->error) {
527 skb_push(skb, skb->data - skb_network_header(skb));
528 dst_input(skb);
529 return -1;
530 }
531
532 if (skb->dst->dev->flags&IFF_LOOPBACK) {
533 if (ipv6_hdr(skb)->hop_limit <= 1) {
534 IP6_INC_STATS_BH(ip6_dst_idev(skb->dst),
535 IPSTATS_MIB_INHDRERRORS);
536 icmpv6_send(skb, ICMPV6_TIME_EXCEED, ICMPV6_EXC_HOPLIMIT,
537 0, skb->dev);
538 kfree_skb(skb);
539 return -1;
540 }
541 ipv6_hdr(skb)->hop_limit--;
542 goto looped_back;
543 }
544
545 skb_push(skb, skb->data - skb_network_header(skb));
546 dst_input(skb);
547 return -1;
548
549 unknown_rh:
550 IP6_INC_STATS_BH(ip6_dst_idev(skb->dst), IPSTATS_MIB_INHDRERRORS);
551 icmpv6_param_prob(skb, ICMPV6_HDR_FIELD,
552 (&hdr->type) - skb_network_header(skb));
553 return -1;
554 }
555
556 static struct inet6_protocol rthdr_protocol = {
557 .handler = ipv6_rthdr_rcv,
558 .flags = INET6_PROTO_NOPOLICY | INET6_PROTO_GSO_EXTHDR,
559 };
560
561 void __init ipv6_rthdr_init(void)
562 {
563 if (inet6_add_protocol(&rthdr_protocol, IPPROTO_ROUTING) < 0)
564 printk(KERN_ERR "ipv6_rthdr_init: Could not register protocol\n");
565 };
566
567 /**********************************
568 Hop-by-hop options.
569 **********************************/
570
571 /*
572 * Note: we cannot rely on skb->dst before we assign it in ip6_route_input().
573 */
574 static inline struct inet6_dev *ipv6_skb_idev(struct sk_buff *skb)
575 {
576 return skb->dst ? ip6_dst_idev(skb->dst) : __in6_dev_get(skb->dev);
577 }
578
579 /* Router Alert as of RFC 2711 */
580
581 static int ipv6_hop_ra(struct sk_buff **skbp, int optoff)
582 {
583 struct sk_buff *skb = *skbp;
584 const unsigned char *nh = skb_network_header(skb);
585
586 if (nh[optoff + 1] == 2) {
587 IP6CB(skb)->ra = optoff;
588 return 1;
589 }
590 LIMIT_NETDEBUG(KERN_DEBUG "ipv6_hop_ra: wrong RA length %d\n",
591 nh[optoff + 1]);
592 kfree_skb(skb);
593 return 0;
594 }
595
596 /* Jumbo payload */
597
598 static int ipv6_hop_jumbo(struct sk_buff **skbp, int optoff)
599 {
600 struct sk_buff *skb = *skbp;
601 const unsigned char *nh = skb_network_header(skb);
602 u32 pkt_len;
603
604 if (nh[optoff + 1] != 4 || (optoff & 3) != 2) {
605 LIMIT_NETDEBUG(KERN_DEBUG "ipv6_hop_jumbo: wrong jumbo opt length/alignment %d\n",
606 nh[optoff+1]);
607 IP6_INC_STATS_BH(ipv6_skb_idev(skb),
608 IPSTATS_MIB_INHDRERRORS);
609 goto drop;
610 }
611
612 pkt_len = ntohl(*(__be32 *)(nh + optoff + 2));
613 if (pkt_len <= IPV6_MAXPLEN) {
614 IP6_INC_STATS_BH(ipv6_skb_idev(skb), IPSTATS_MIB_INHDRERRORS);
615 icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, optoff+2);
616 return 0;
617 }
618 if (ipv6_hdr(skb)->payload_len) {
619 IP6_INC_STATS_BH(ipv6_skb_idev(skb), IPSTATS_MIB_INHDRERRORS);
620 icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, optoff);
621 return 0;
622 }
623
624 if (pkt_len > skb->len - sizeof(struct ipv6hdr)) {
625 IP6_INC_STATS_BH(ipv6_skb_idev(skb), IPSTATS_MIB_INTRUNCATEDPKTS);
626 goto drop;
627 }
628
629 if (pskb_trim_rcsum(skb, pkt_len + sizeof(struct ipv6hdr)))
630 goto drop;
631
632 return 1;
633
634 drop:
635 kfree_skb(skb);
636 return 0;
637 }
638
639 static struct tlvtype_proc tlvprochopopt_lst[] = {
640 {
641 .type = IPV6_TLV_ROUTERALERT,
642 .func = ipv6_hop_ra,
643 },
644 {
645 .type = IPV6_TLV_JUMBO,
646 .func = ipv6_hop_jumbo,
647 },
648 { -1, }
649 };
650
651 int ipv6_parse_hopopts(struct sk_buff **skbp)
652 {
653 struct sk_buff *skb = *skbp;
654 struct inet6_skb_parm *opt = IP6CB(skb);
655
656 /*
657 * skb_network_header(skb) is equal to skb->data, and
658 * skb_network_header_len(skb) is always equal to
659 * sizeof(struct ipv6hdr) by definition of
660 * hop-by-hop options.
661 */
662 if (!pskb_may_pull(skb, sizeof(struct ipv6hdr) + 8) ||
663 !pskb_may_pull(skb, (sizeof(struct ipv6hdr) +
664 ((skb_transport_header(skb)[1] + 1) << 3)))) {
665 kfree_skb(skb);
666 return -1;
667 }
668
669 opt->hop = sizeof(struct ipv6hdr);
670 if (ip6_parse_tlv(tlvprochopopt_lst, skbp)) {
671 skb = *skbp;
672 skb->transport_header += (skb_transport_header(skb)[1] + 1) << 3;
673 opt = IP6CB(skb);
674 opt->nhoff = sizeof(struct ipv6hdr);
675 return 1;
676 }
677 return -1;
678 }
679
680 /*
681 * Creating outbound headers.
682 *
683 * "build" functions work when skb is filled from head to tail (datagram)
684 * "push" functions work when headers are added from tail to head (tcp)
685 *
686 * In both cases we assume, that caller reserved enough room
687 * for headers.
688 */
689
690 static void ipv6_push_rthdr(struct sk_buff *skb, u8 *proto,
691 struct ipv6_rt_hdr *opt,
692 struct in6_addr **addr_p)
693 {
694 struct rt0_hdr *phdr, *ihdr;
695 int hops;
696
697 ihdr = (struct rt0_hdr *) opt;
698
699 phdr = (struct rt0_hdr *) skb_push(skb, (ihdr->rt_hdr.hdrlen + 1) << 3);
700 memcpy(phdr, ihdr, sizeof(struct rt0_hdr));
701
702 hops = ihdr->rt_hdr.hdrlen >> 1;
703
704 if (hops > 1)
705 memcpy(phdr->addr, ihdr->addr + 1,
706 (hops - 1) * sizeof(struct in6_addr));
707
708 ipv6_addr_copy(phdr->addr + (hops - 1), *addr_p);
709 *addr_p = ihdr->addr;
710
711 phdr->rt_hdr.nexthdr = *proto;
712 *proto = NEXTHDR_ROUTING;
713 }
714
715 static void ipv6_push_exthdr(struct sk_buff *skb, u8 *proto, u8 type, struct ipv6_opt_hdr *opt)
716 {
717 struct ipv6_opt_hdr *h = (struct ipv6_opt_hdr *)skb_push(skb, ipv6_optlen(opt));
718
719 memcpy(h, opt, ipv6_optlen(opt));
720 h->nexthdr = *proto;
721 *proto = type;
722 }
723
724 void ipv6_push_nfrag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt,
725 u8 *proto,
726 struct in6_addr **daddr)
727 {
728 if (opt->srcrt) {
729 ipv6_push_rthdr(skb, proto, opt->srcrt, daddr);
730 /*
731 * IPV6_RTHDRDSTOPTS is ignored
732 * unless IPV6_RTHDR is set (RFC3542).
733 */
734 if (opt->dst0opt)
735 ipv6_push_exthdr(skb, proto, NEXTHDR_DEST, opt->dst0opt);
736 }
737 if (opt->hopopt)
738 ipv6_push_exthdr(skb, proto, NEXTHDR_HOP, opt->hopopt);
739 }
740
741 EXPORT_SYMBOL(ipv6_push_nfrag_opts);
742
743 void ipv6_push_frag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt, u8 *proto)
744 {
745 if (opt->dst1opt)
746 ipv6_push_exthdr(skb, proto, NEXTHDR_DEST, opt->dst1opt);
747 }
748
749 struct ipv6_txoptions *
750 ipv6_dup_options(struct sock *sk, struct ipv6_txoptions *opt)
751 {
752 struct ipv6_txoptions *opt2;
753
754 opt2 = sock_kmalloc(sk, opt->tot_len, GFP_ATOMIC);
755 if (opt2) {
756 long dif = (char*)opt2 - (char*)opt;
757 memcpy(opt2, opt, opt->tot_len);
758 if (opt2->hopopt)
759 *((char**)&opt2->hopopt) += dif;
760 if (opt2->dst0opt)
761 *((char**)&opt2->dst0opt) += dif;
762 if (opt2->dst1opt)
763 *((char**)&opt2->dst1opt) += dif;
764 if (opt2->srcrt)
765 *((char**)&opt2->srcrt) += dif;
766 }
767 return opt2;
768 }
769
770 EXPORT_SYMBOL_GPL(ipv6_dup_options);
771
772 static int ipv6_renew_option(void *ohdr,
773 struct ipv6_opt_hdr __user *newopt, int newoptlen,
774 int inherit,
775 struct ipv6_opt_hdr **hdr,
776 char **p)
777 {
778 if (inherit) {
779 if (ohdr) {
780 memcpy(*p, ohdr, ipv6_optlen((struct ipv6_opt_hdr *)ohdr));
781 *hdr = (struct ipv6_opt_hdr *)*p;
782 *p += CMSG_ALIGN(ipv6_optlen(*(struct ipv6_opt_hdr **)hdr));
783 }
784 } else {
785 if (newopt) {
786 if (copy_from_user(*p, newopt, newoptlen))
787 return -EFAULT;
788 *hdr = (struct ipv6_opt_hdr *)*p;
789 if (ipv6_optlen(*(struct ipv6_opt_hdr **)hdr) > newoptlen)
790 return -EINVAL;
791 *p += CMSG_ALIGN(newoptlen);
792 }
793 }
794 return 0;
795 }
796
797 struct ipv6_txoptions *
798 ipv6_renew_options(struct sock *sk, struct ipv6_txoptions *opt,
799 int newtype,
800 struct ipv6_opt_hdr __user *newopt, int newoptlen)
801 {
802 int tot_len = 0;
803 char *p;
804 struct ipv6_txoptions *opt2;
805 int err;
806
807 if (opt) {
808 if (newtype != IPV6_HOPOPTS && opt->hopopt)
809 tot_len += CMSG_ALIGN(ipv6_optlen(opt->hopopt));
810 if (newtype != IPV6_RTHDRDSTOPTS && opt->dst0opt)
811 tot_len += CMSG_ALIGN(ipv6_optlen(opt->dst0opt));
812 if (newtype != IPV6_RTHDR && opt->srcrt)
813 tot_len += CMSG_ALIGN(ipv6_optlen(opt->srcrt));
814 if (newtype != IPV6_DSTOPTS && opt->dst1opt)
815 tot_len += CMSG_ALIGN(ipv6_optlen(opt->dst1opt));
816 }
817
818 if (newopt && newoptlen)
819 tot_len += CMSG_ALIGN(newoptlen);
820
821 if (!tot_len)
822 return NULL;
823
824 tot_len += sizeof(*opt2);
825 opt2 = sock_kmalloc(sk, tot_len, GFP_ATOMIC);
826 if (!opt2)
827 return ERR_PTR(-ENOBUFS);
828
829 memset(opt2, 0, tot_len);
830
831 opt2->tot_len = tot_len;
832 p = (char *)(opt2 + 1);
833
834 err = ipv6_renew_option(opt ? opt->hopopt : NULL, newopt, newoptlen,
835 newtype != IPV6_HOPOPTS,
836 &opt2->hopopt, &p);
837 if (err)
838 goto out;
839
840 err = ipv6_renew_option(opt ? opt->dst0opt : NULL, newopt, newoptlen,
841 newtype != IPV6_RTHDRDSTOPTS,
842 &opt2->dst0opt, &p);
843 if (err)
844 goto out;
845
846 err = ipv6_renew_option(opt ? opt->srcrt : NULL, newopt, newoptlen,
847 newtype != IPV6_RTHDR,
848 (struct ipv6_opt_hdr **)&opt2->srcrt, &p);
849 if (err)
850 goto out;
851
852 err = ipv6_renew_option(opt ? opt->dst1opt : NULL, newopt, newoptlen,
853 newtype != IPV6_DSTOPTS,
854 &opt2->dst1opt, &p);
855 if (err)
856 goto out;
857
858 opt2->opt_nflen = (opt2->hopopt ? ipv6_optlen(opt2->hopopt) : 0) +
859 (opt2->dst0opt ? ipv6_optlen(opt2->dst0opt) : 0) +
860 (opt2->srcrt ? ipv6_optlen(opt2->srcrt) : 0);
861 opt2->opt_flen = (opt2->dst1opt ? ipv6_optlen(opt2->dst1opt) : 0);
862
863 return opt2;
864 out:
865 sock_kfree_s(sk, opt2, opt2->tot_len);
866 return ERR_PTR(err);
867 }
868
869 struct ipv6_txoptions *ipv6_fixup_options(struct ipv6_txoptions *opt_space,
870 struct ipv6_txoptions *opt)
871 {
872 /*
873 * ignore the dest before srcrt unless srcrt is being included.
874 * --yoshfuji
875 */
876 if (opt && opt->dst0opt && !opt->srcrt) {
877 if (opt_space != opt) {
878 memcpy(opt_space, opt, sizeof(*opt_space));
879 opt = opt_space;
880 }
881 opt->opt_nflen -= ipv6_optlen(opt->dst0opt);
882 opt->dst0opt = NULL;
883 }
884
885 return opt;
886 }
887
Linus' kernel tree