Commit | Line | Data |
---|---|---|
1da177e4 LT |
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/sched.h> | |
31 | #include <linux/net.h> | |
32 | #include <linux/netdevice.h> | |
33 | #include <linux/in6.h> | |
34 | #include <linux/icmpv6.h> | |
35 | ||
36 | #include <net/sock.h> | |
37 | #include <net/snmp.h> | |
38 | ||
39 | #include <net/ipv6.h> | |
40 | #include <net/protocol.h> | |
41 | #include <net/transp_v6.h> | |
42 | #include <net/rawv6.h> | |
43 | #include <net/ndisc.h> | |
44 | #include <net/ip6_route.h> | |
45 | #include <net/addrconf.h> | |
65d4ed92 MN |
46 | #ifdef CONFIG_IPV6_MIP6 |
47 | #include <net/xfrm.h> | |
48 | #endif | |
1da177e4 LT |
49 | |
50 | #include <asm/uaccess.h> | |
51 | ||
c61a4043 MN |
52 | int ipv6_find_tlv(struct sk_buff *skb, int offset, int type) |
53 | { | |
54 | int packet_len = skb->tail - skb->nh.raw; | |
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*)(skb->nh.raw + 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 = skb->nh.raw[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 = skb->nh.raw[offset + 1] + 2; | |
82 | if (optlen > len) | |
83 | goto bad; | |
84 | break; | |
85 | } | |
86 | offset += optlen; | |
87 | len -= optlen; | |
88 | } | |
89 | /* not_found */ | |
90 | return -1; | |
91 | bad: | |
92 | return -1; | |
93 | } | |
94 | ||
1da177e4 LT |
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; | |
a80ff03e | 105 | int (*func)(struct sk_buff **skbp, int offset); |
1da177e4 LT |
106 | }; |
107 | ||
108 | /********************* | |
109 | Generic functions | |
110 | *********************/ | |
111 | ||
112 | /* An unknown option is detected, decide what to do */ | |
113 | ||
a80ff03e | 114 | static int ip6_tlvopt_unknown(struct sk_buff **skbp, int optoff) |
1da177e4 | 115 | { |
a80ff03e MN |
116 | struct sk_buff *skb = *skbp; |
117 | ||
1da177e4 LT |
118 | switch ((skb->nh.raw[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(&skb->nh.ipv6h->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 | ||
a80ff03e | 142 | static int ip6_parse_tlv(struct tlvtype_proc *procs, struct sk_buff **skbp) |
1da177e4 | 143 | { |
a80ff03e | 144 | struct sk_buff *skb = *skbp; |
1da177e4 LT |
145 | struct tlvtype_proc *curr; |
146 | int off = skb->h.raw - skb->nh.raw; | |
147 | int len = ((skb->h.raw[1]+1)<<3); | |
148 | ||
149 | if ((skb->h.raw + len) - skb->data > skb_headlen(skb)) | |
150 | goto bad; | |
151 | ||
152 | off += 2; | |
153 | len -= 2; | |
154 | ||
155 | while (len > 0) { | |
156 | int optlen = skb->nh.raw[off+1]+2; | |
157 | ||
158 | switch (skb->nh.raw[off]) { | |
159 | case IPV6_TLV_PAD0: | |
160 | optlen = 1; | |
161 | break; | |
162 | ||
163 | case IPV6_TLV_PADN: | |
164 | break; | |
165 | ||
166 | default: /* Other TLV code so scan list */ | |
167 | if (optlen > len) | |
168 | goto bad; | |
169 | for (curr=procs; curr->type >= 0; curr++) { | |
170 | if (curr->type == skb->nh.raw[off]) { | |
171 | /* type specific length/alignment | |
172 | checks will be performed in the | |
173 | func(). */ | |
a80ff03e | 174 | if (curr->func(skbp, off) == 0) |
1da177e4 LT |
175 | return 0; |
176 | break; | |
177 | } | |
178 | } | |
179 | if (curr->type < 0) { | |
a80ff03e | 180 | if (ip6_tlvopt_unknown(skbp, off) == 0) |
1da177e4 LT |
181 | return 0; |
182 | } | |
183 | break; | |
184 | } | |
185 | off += optlen; | |
186 | len -= optlen; | |
187 | } | |
188 | if (len == 0) | |
189 | return 1; | |
190 | bad: | |
191 | kfree_skb(skb); | |
192 | return 0; | |
193 | } | |
194 | ||
195 | /***************************** | |
196 | Destination options header. | |
197 | *****************************/ | |
198 | ||
199 | static struct tlvtype_proc tlvprocdestopt_lst[] = { | |
200 | /* No destination options are defined now */ | |
201 | {-1, NULL} | |
202 | }; | |
203 | ||
951dbc8a | 204 | static int ipv6_destopt_rcv(struct sk_buff **skbp) |
1da177e4 LT |
205 | { |
206 | struct sk_buff *skb = *skbp; | |
207 | struct inet6_skb_parm *opt = IP6CB(skb); | |
208 | ||
209 | if (!pskb_may_pull(skb, (skb->h.raw-skb->data)+8) || | |
210 | !pskb_may_pull(skb, (skb->h.raw-skb->data)+((skb->h.raw[1]+1)<<3))) { | |
211 | IP6_INC_STATS_BH(IPSTATS_MIB_INHDRERRORS); | |
212 | kfree_skb(skb); | |
213 | return -1; | |
214 | } | |
215 | ||
333fad53 | 216 | opt->lastopt = skb->h.raw - skb->nh.raw; |
1da177e4 LT |
217 | opt->dst1 = skb->h.raw - skb->nh.raw; |
218 | ||
a80ff03e MN |
219 | if (ip6_parse_tlv(tlvprocdestopt_lst, skbp)) { |
220 | skb = *skbp; | |
1da177e4 | 221 | skb->h.raw += ((skb->h.raw[1]+1)<<3); |
951dbc8a | 222 | opt->nhoff = opt->dst1; |
1da177e4 LT |
223 | return 1; |
224 | } | |
225 | ||
226 | IP6_INC_STATS_BH(IPSTATS_MIB_INHDRERRORS); | |
227 | return -1; | |
228 | } | |
229 | ||
230 | static struct inet6_protocol destopt_protocol = { | |
231 | .handler = ipv6_destopt_rcv, | |
adcfc7d0 | 232 | .flags = INET6_PROTO_NOPOLICY | INET6_PROTO_GSO_EXTHDR, |
1da177e4 LT |
233 | }; |
234 | ||
235 | void __init ipv6_destopt_init(void) | |
236 | { | |
237 | if (inet6_add_protocol(&destopt_protocol, IPPROTO_DSTOPTS) < 0) | |
238 | printk(KERN_ERR "ipv6_destopt_init: Could not register protocol\n"); | |
239 | } | |
240 | ||
241 | /******************************** | |
242 | NONE header. No data in packet. | |
243 | ********************************/ | |
244 | ||
951dbc8a | 245 | static int ipv6_nodata_rcv(struct sk_buff **skbp) |
1da177e4 LT |
246 | { |
247 | struct sk_buff *skb = *skbp; | |
248 | ||
249 | kfree_skb(skb); | |
250 | return 0; | |
251 | } | |
252 | ||
253 | static struct inet6_protocol nodata_protocol = { | |
254 | .handler = ipv6_nodata_rcv, | |
255 | .flags = INET6_PROTO_NOPOLICY, | |
256 | }; | |
257 | ||
258 | void __init ipv6_nodata_init(void) | |
259 | { | |
260 | if (inet6_add_protocol(&nodata_protocol, IPPROTO_NONE) < 0) | |
261 | printk(KERN_ERR "ipv6_nodata_init: Could not register protocol\n"); | |
262 | } | |
263 | ||
264 | /******************************** | |
265 | Routing header. | |
266 | ********************************/ | |
267 | ||
951dbc8a | 268 | static int ipv6_rthdr_rcv(struct sk_buff **skbp) |
1da177e4 LT |
269 | { |
270 | struct sk_buff *skb = *skbp; | |
271 | struct inet6_skb_parm *opt = IP6CB(skb); | |
65d4ed92 | 272 | struct in6_addr *addr = NULL; |
1da177e4 LT |
273 | struct in6_addr daddr; |
274 | int n, i; | |
275 | ||
276 | struct ipv6_rt_hdr *hdr; | |
277 | struct rt0_hdr *rthdr; | |
278 | ||
279 | if (!pskb_may_pull(skb, (skb->h.raw-skb->data)+8) || | |
280 | !pskb_may_pull(skb, (skb->h.raw-skb->data)+((skb->h.raw[1]+1)<<3))) { | |
281 | IP6_INC_STATS_BH(IPSTATS_MIB_INHDRERRORS); | |
282 | kfree_skb(skb); | |
283 | return -1; | |
284 | } | |
285 | ||
286 | hdr = (struct ipv6_rt_hdr *) skb->h.raw; | |
287 | ||
288 | if (ipv6_addr_is_multicast(&skb->nh.ipv6h->daddr) || | |
289 | skb->pkt_type != PACKET_HOST) { | |
290 | IP6_INC_STATS_BH(IPSTATS_MIB_INADDRERRORS); | |
291 | kfree_skb(skb); | |
292 | return -1; | |
293 | } | |
294 | ||
295 | looped_back: | |
296 | if (hdr->segments_left == 0) { | |
65d4ed92 MN |
297 | switch (hdr->type) { |
298 | #ifdef CONFIG_IPV6_MIP6 | |
299 | case IPV6_SRCRT_TYPE_2: | |
300 | /* Silently discard type 2 header unless it was | |
301 | * processed by own | |
302 | */ | |
303 | if (!addr) { | |
304 | IP6_INC_STATS_BH(IPSTATS_MIB_INADDRERRORS); | |
305 | kfree_skb(skb); | |
306 | return -1; | |
307 | } | |
308 | break; | |
309 | #endif | |
310 | default: | |
311 | break; | |
312 | } | |
313 | ||
333fad53 | 314 | opt->lastopt = skb->h.raw - skb->nh.raw; |
1da177e4 LT |
315 | opt->srcrt = skb->h.raw - skb->nh.raw; |
316 | skb->h.raw += (hdr->hdrlen + 1) << 3; | |
317 | opt->dst0 = opt->dst1; | |
318 | opt->dst1 = 0; | |
951dbc8a | 319 | opt->nhoff = (&hdr->nexthdr) - skb->nh.raw; |
1da177e4 LT |
320 | return 1; |
321 | } | |
322 | ||
65d4ed92 MN |
323 | switch (hdr->type) { |
324 | case IPV6_SRCRT_TYPE_0: | |
325 | if (hdr->hdrlen & 0x01) { | |
326 | IP6_INC_STATS_BH(IPSTATS_MIB_INHDRERRORS); | |
327 | icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, (&hdr->hdrlen) - skb->nh.raw); | |
328 | return -1; | |
329 | } | |
330 | break; | |
331 | #ifdef CONFIG_IPV6_MIP6 | |
332 | case IPV6_SRCRT_TYPE_2: | |
333 | /* Silently discard invalid RTH type 2 */ | |
334 | if (hdr->hdrlen != 2 || hdr->segments_left != 1) { | |
335 | IP6_INC_STATS_BH(IPSTATS_MIB_INHDRERRORS); | |
336 | kfree_skb(skb); | |
337 | return -1; | |
338 | } | |
339 | break; | |
340 | #endif | |
341 | default: | |
1da177e4 LT |
342 | IP6_INC_STATS_BH(IPSTATS_MIB_INHDRERRORS); |
343 | icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, (&hdr->type) - skb->nh.raw); | |
344 | return -1; | |
345 | } | |
1da177e4 LT |
346 | |
347 | /* | |
348 | * This is the routing header forwarding algorithm from | |
349 | * RFC 2460, page 16. | |
350 | */ | |
351 | ||
352 | n = hdr->hdrlen >> 1; | |
353 | ||
354 | if (hdr->segments_left > n) { | |
355 | IP6_INC_STATS_BH(IPSTATS_MIB_INHDRERRORS); | |
356 | icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, (&hdr->segments_left) - skb->nh.raw); | |
357 | return -1; | |
358 | } | |
359 | ||
360 | /* We are about to mangle packet header. Be careful! | |
361 | Do not damage packets queued somewhere. | |
362 | */ | |
363 | if (skb_cloned(skb)) { | |
364 | struct sk_buff *skb2 = skb_copy(skb, GFP_ATOMIC); | |
365 | kfree_skb(skb); | |
366 | /* the copy is a forwarded packet */ | |
367 | if (skb2 == NULL) { | |
368 | IP6_INC_STATS_BH(IPSTATS_MIB_OUTDISCARDS); | |
369 | return -1; | |
370 | } | |
371 | *skbp = skb = skb2; | |
372 | opt = IP6CB(skb2); | |
373 | hdr = (struct ipv6_rt_hdr *) skb2->h.raw; | |
374 | } | |
375 | ||
84fa7933 | 376 | if (skb->ip_summed == CHECKSUM_COMPLETE) |
1da177e4 LT |
377 | skb->ip_summed = CHECKSUM_NONE; |
378 | ||
379 | i = n - --hdr->segments_left; | |
380 | ||
381 | rthdr = (struct rt0_hdr *) hdr; | |
382 | addr = rthdr->addr; | |
383 | addr += i - 1; | |
384 | ||
65d4ed92 MN |
385 | switch (hdr->type) { |
386 | #ifdef CONFIG_IPV6_MIP6 | |
387 | case IPV6_SRCRT_TYPE_2: | |
388 | if (xfrm6_input_addr(skb, (xfrm_address_t *)addr, | |
389 | (xfrm_address_t *)&skb->nh.ipv6h->saddr, | |
390 | IPPROTO_ROUTING) < 0) { | |
391 | IP6_INC_STATS_BH(IPSTATS_MIB_INADDRERRORS); | |
392 | kfree_skb(skb); | |
393 | return -1; | |
394 | } | |
395 | if (!ipv6_chk_home_addr(addr)) { | |
396 | IP6_INC_STATS_BH(IPSTATS_MIB_INADDRERRORS); | |
397 | kfree_skb(skb); | |
398 | return -1; | |
399 | } | |
400 | break; | |
401 | #endif | |
402 | default: | |
403 | break; | |
404 | } | |
405 | ||
1da177e4 LT |
406 | if (ipv6_addr_is_multicast(addr)) { |
407 | IP6_INC_STATS_BH(IPSTATS_MIB_INADDRERRORS); | |
408 | kfree_skb(skb); | |
409 | return -1; | |
410 | } | |
411 | ||
412 | ipv6_addr_copy(&daddr, addr); | |
413 | ipv6_addr_copy(addr, &skb->nh.ipv6h->daddr); | |
414 | ipv6_addr_copy(&skb->nh.ipv6h->daddr, &daddr); | |
415 | ||
416 | dst_release(xchg(&skb->dst, NULL)); | |
417 | ip6_route_input(skb); | |
418 | if (skb->dst->error) { | |
419 | skb_push(skb, skb->data - skb->nh.raw); | |
420 | dst_input(skb); | |
421 | return -1; | |
422 | } | |
423 | ||
424 | if (skb->dst->dev->flags&IFF_LOOPBACK) { | |
425 | if (skb->nh.ipv6h->hop_limit <= 1) { | |
426 | IP6_INC_STATS_BH(IPSTATS_MIB_INHDRERRORS); | |
427 | icmpv6_send(skb, ICMPV6_TIME_EXCEED, ICMPV6_EXC_HOPLIMIT, | |
428 | 0, skb->dev); | |
429 | kfree_skb(skb); | |
430 | return -1; | |
431 | } | |
432 | skb->nh.ipv6h->hop_limit--; | |
433 | goto looped_back; | |
434 | } | |
435 | ||
436 | skb_push(skb, skb->data - skb->nh.raw); | |
437 | dst_input(skb); | |
438 | return -1; | |
439 | } | |
440 | ||
441 | static struct inet6_protocol rthdr_protocol = { | |
442 | .handler = ipv6_rthdr_rcv, | |
adcfc7d0 | 443 | .flags = INET6_PROTO_NOPOLICY | INET6_PROTO_GSO_EXTHDR, |
1da177e4 LT |
444 | }; |
445 | ||
446 | void __init ipv6_rthdr_init(void) | |
447 | { | |
448 | if (inet6_add_protocol(&rthdr_protocol, IPPROTO_ROUTING) < 0) | |
449 | printk(KERN_ERR "ipv6_rthdr_init: Could not register protocol\n"); | |
450 | }; | |
451 | ||
452 | /* | |
453 | This function inverts received rthdr. | |
454 | NOTE: specs allow to make it automatically only if | |
455 | packet authenticated. | |
456 | ||
457 | I will not discuss it here (though, I am really pissed off at | |
458 | this stupid requirement making rthdr idea useless) | |
459 | ||
460 | Actually, it creates severe problems for us. | |
461 | Embryonic requests has no associated sockets, | |
462 | so that user have no control over it and | |
463 | cannot not only to set reply options, but | |
464 | even to know, that someone wants to connect | |
465 | without success. :-( | |
466 | ||
467 | For now we need to test the engine, so that I created | |
468 | temporary (or permanent) backdoor. | |
469 | If listening socket set IPV6_RTHDR to 2, then we invert header. | |
470 | --ANK (980729) | |
471 | */ | |
472 | ||
473 | struct ipv6_txoptions * | |
474 | ipv6_invert_rthdr(struct sock *sk, struct ipv6_rt_hdr *hdr) | |
475 | { | |
476 | /* Received rthdr: | |
477 | ||
478 | [ H1 -> H2 -> ... H_prev ] daddr=ME | |
479 | ||
480 | Inverted result: | |
481 | [ H_prev -> ... -> H1 ] daddr =sender | |
482 | ||
483 | Note, that IP output engine will rewrite this rthdr | |
484 | by rotating it left by one addr. | |
485 | */ | |
486 | ||
487 | int n, i; | |
488 | struct rt0_hdr *rthdr = (struct rt0_hdr*)hdr; | |
489 | struct rt0_hdr *irthdr; | |
490 | struct ipv6_txoptions *opt; | |
491 | int hdrlen = ipv6_optlen(hdr); | |
492 | ||
493 | if (hdr->segments_left || | |
494 | hdr->type != IPV6_SRCRT_TYPE_0 || | |
495 | hdr->hdrlen & 0x01) | |
496 | return NULL; | |
497 | ||
498 | n = hdr->hdrlen >> 1; | |
499 | opt = sock_kmalloc(sk, sizeof(*opt) + hdrlen, GFP_ATOMIC); | |
500 | if (opt == NULL) | |
501 | return NULL; | |
502 | memset(opt, 0, sizeof(*opt)); | |
503 | opt->tot_len = sizeof(*opt) + hdrlen; | |
504 | opt->srcrt = (void*)(opt+1); | |
505 | opt->opt_nflen = hdrlen; | |
506 | ||
507 | memcpy(opt->srcrt, hdr, sizeof(*hdr)); | |
508 | irthdr = (struct rt0_hdr*)opt->srcrt; | |
e6df439b | 509 | irthdr->reserved = 0; |
1da177e4 LT |
510 | opt->srcrt->segments_left = n; |
511 | for (i=0; i<n; i++) | |
512 | memcpy(irthdr->addr+i, rthdr->addr+(n-1-i), 16); | |
513 | return opt; | |
514 | } | |
515 | ||
3cf3dc6c ACM |
516 | EXPORT_SYMBOL_GPL(ipv6_invert_rthdr); |
517 | ||
1da177e4 LT |
518 | /********************************** |
519 | Hop-by-hop options. | |
520 | **********************************/ | |
521 | ||
522 | /* Router Alert as of RFC 2711 */ | |
523 | ||
a80ff03e | 524 | static int ipv6_hop_ra(struct sk_buff **skbp, int optoff) |
1da177e4 | 525 | { |
a80ff03e MN |
526 | struct sk_buff *skb = *skbp; |
527 | ||
1da177e4 LT |
528 | if (skb->nh.raw[optoff+1] == 2) { |
529 | IP6CB(skb)->ra = optoff; | |
530 | return 1; | |
531 | } | |
64ce2073 PM |
532 | LIMIT_NETDEBUG(KERN_DEBUG "ipv6_hop_ra: wrong RA length %d\n", |
533 | skb->nh.raw[optoff+1]); | |
1da177e4 LT |
534 | kfree_skb(skb); |
535 | return 0; | |
536 | } | |
537 | ||
538 | /* Jumbo payload */ | |
539 | ||
a80ff03e | 540 | static int ipv6_hop_jumbo(struct sk_buff **skbp, int optoff) |
1da177e4 | 541 | { |
a80ff03e | 542 | struct sk_buff *skb = *skbp; |
1da177e4 LT |
543 | u32 pkt_len; |
544 | ||
545 | if (skb->nh.raw[optoff+1] != 4 || (optoff&3) != 2) { | |
64ce2073 PM |
546 | LIMIT_NETDEBUG(KERN_DEBUG "ipv6_hop_jumbo: wrong jumbo opt length/alignment %d\n", |
547 | skb->nh.raw[optoff+1]); | |
1da177e4 LT |
548 | IP6_INC_STATS_BH(IPSTATS_MIB_INHDRERRORS); |
549 | goto drop; | |
550 | } | |
551 | ||
552 | pkt_len = ntohl(*(u32*)(skb->nh.raw+optoff+2)); | |
553 | if (pkt_len <= IPV6_MAXPLEN) { | |
554 | IP6_INC_STATS_BH(IPSTATS_MIB_INHDRERRORS); | |
555 | icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, optoff+2); | |
556 | return 0; | |
557 | } | |
558 | if (skb->nh.ipv6h->payload_len) { | |
559 | IP6_INC_STATS_BH(IPSTATS_MIB_INHDRERRORS); | |
560 | icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, optoff); | |
561 | return 0; | |
562 | } | |
563 | ||
564 | if (pkt_len > skb->len - sizeof(struct ipv6hdr)) { | |
565 | IP6_INC_STATS_BH(IPSTATS_MIB_INTRUNCATEDPKTS); | |
566 | goto drop; | |
567 | } | |
42ca89c1 SH |
568 | |
569 | if (pskb_trim_rcsum(skb, pkt_len + sizeof(struct ipv6hdr))) | |
570 | goto drop; | |
571 | ||
1da177e4 LT |
572 | return 1; |
573 | ||
574 | drop: | |
575 | kfree_skb(skb); | |
576 | return 0; | |
577 | } | |
578 | ||
579 | static struct tlvtype_proc tlvprochopopt_lst[] = { | |
580 | { | |
581 | .type = IPV6_TLV_ROUTERALERT, | |
582 | .func = ipv6_hop_ra, | |
583 | }, | |
584 | { | |
585 | .type = IPV6_TLV_JUMBO, | |
586 | .func = ipv6_hop_jumbo, | |
587 | }, | |
588 | { -1, } | |
589 | }; | |
590 | ||
a80ff03e | 591 | int ipv6_parse_hopopts(struct sk_buff **skbp) |
1da177e4 | 592 | { |
a80ff03e | 593 | struct sk_buff *skb = *skbp; |
951dbc8a PM |
594 | struct inet6_skb_parm *opt = IP6CB(skb); |
595 | ||
ec670095 YH |
596 | /* |
597 | * skb->nh.raw is equal to skb->data, and | |
598 | * skb->h.raw - skb->nh.raw is always equal to | |
599 | * sizeof(struct ipv6hdr) by definition of | |
600 | * hop-by-hop options. | |
601 | */ | |
602 | if (!pskb_may_pull(skb, sizeof(struct ipv6hdr) + 8) || | |
603 | !pskb_may_pull(skb, sizeof(struct ipv6hdr) + ((skb->h.raw[1] + 1) << 3))) { | |
604 | kfree_skb(skb); | |
605 | return -1; | |
606 | } | |
607 | ||
951dbc8a | 608 | opt->hop = sizeof(struct ipv6hdr); |
a80ff03e MN |
609 | if (ip6_parse_tlv(tlvprochopopt_lst, skbp)) { |
610 | skb = *skbp; | |
951dbc8a PM |
611 | skb->h.raw += (skb->h.raw[1]+1)<<3; |
612 | opt->nhoff = sizeof(struct ipv6hdr); | |
b809739a | 613 | return 1; |
951dbc8a | 614 | } |
1da177e4 LT |
615 | return -1; |
616 | } | |
617 | ||
618 | /* | |
619 | * Creating outbound headers. | |
620 | * | |
621 | * "build" functions work when skb is filled from head to tail (datagram) | |
622 | * "push" functions work when headers are added from tail to head (tcp) | |
623 | * | |
624 | * In both cases we assume, that caller reserved enough room | |
625 | * for headers. | |
626 | */ | |
627 | ||
628 | static void ipv6_push_rthdr(struct sk_buff *skb, u8 *proto, | |
629 | struct ipv6_rt_hdr *opt, | |
630 | struct in6_addr **addr_p) | |
631 | { | |
632 | struct rt0_hdr *phdr, *ihdr; | |
633 | int hops; | |
634 | ||
635 | ihdr = (struct rt0_hdr *) opt; | |
636 | ||
637 | phdr = (struct rt0_hdr *) skb_push(skb, (ihdr->rt_hdr.hdrlen + 1) << 3); | |
638 | memcpy(phdr, ihdr, sizeof(struct rt0_hdr)); | |
639 | ||
640 | hops = ihdr->rt_hdr.hdrlen >> 1; | |
641 | ||
642 | if (hops > 1) | |
643 | memcpy(phdr->addr, ihdr->addr + 1, | |
644 | (hops - 1) * sizeof(struct in6_addr)); | |
645 | ||
646 | ipv6_addr_copy(phdr->addr + (hops - 1), *addr_p); | |
647 | *addr_p = ihdr->addr; | |
648 | ||
649 | phdr->rt_hdr.nexthdr = *proto; | |
650 | *proto = NEXTHDR_ROUTING; | |
651 | } | |
652 | ||
653 | static void ipv6_push_exthdr(struct sk_buff *skb, u8 *proto, u8 type, struct ipv6_opt_hdr *opt) | |
654 | { | |
655 | struct ipv6_opt_hdr *h = (struct ipv6_opt_hdr *)skb_push(skb, ipv6_optlen(opt)); | |
656 | ||
657 | memcpy(h, opt, ipv6_optlen(opt)); | |
658 | h->nexthdr = *proto; | |
659 | *proto = type; | |
660 | } | |
661 | ||
662 | void ipv6_push_nfrag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt, | |
663 | u8 *proto, | |
664 | struct in6_addr **daddr) | |
665 | { | |
333fad53 | 666 | if (opt->srcrt) { |
1da177e4 | 667 | ipv6_push_rthdr(skb, proto, opt->srcrt, daddr); |
333fad53 YH |
668 | /* |
669 | * IPV6_RTHDRDSTOPTS is ignored | |
670 | * unless IPV6_RTHDR is set (RFC3542). | |
671 | */ | |
672 | if (opt->dst0opt) | |
673 | ipv6_push_exthdr(skb, proto, NEXTHDR_DEST, opt->dst0opt); | |
674 | } | |
1da177e4 LT |
675 | if (opt->hopopt) |
676 | ipv6_push_exthdr(skb, proto, NEXTHDR_HOP, opt->hopopt); | |
677 | } | |
678 | ||
679 | void ipv6_push_frag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt, u8 *proto) | |
680 | { | |
681 | if (opt->dst1opt) | |
682 | ipv6_push_exthdr(skb, proto, NEXTHDR_DEST, opt->dst1opt); | |
683 | } | |
684 | ||
685 | struct ipv6_txoptions * | |
686 | ipv6_dup_options(struct sock *sk, struct ipv6_txoptions *opt) | |
687 | { | |
688 | struct ipv6_txoptions *opt2; | |
689 | ||
690 | opt2 = sock_kmalloc(sk, opt->tot_len, GFP_ATOMIC); | |
691 | if (opt2) { | |
692 | long dif = (char*)opt2 - (char*)opt; | |
693 | memcpy(opt2, opt, opt->tot_len); | |
694 | if (opt2->hopopt) | |
695 | *((char**)&opt2->hopopt) += dif; | |
696 | if (opt2->dst0opt) | |
697 | *((char**)&opt2->dst0opt) += dif; | |
698 | if (opt2->dst1opt) | |
699 | *((char**)&opt2->dst1opt) += dif; | |
700 | if (opt2->srcrt) | |
701 | *((char**)&opt2->srcrt) += dif; | |
702 | } | |
703 | return opt2; | |
704 | } | |
333fad53 | 705 | |
3cf3dc6c ACM |
706 | EXPORT_SYMBOL_GPL(ipv6_dup_options); |
707 | ||
333fad53 YH |
708 | static int ipv6_renew_option(void *ohdr, |
709 | struct ipv6_opt_hdr __user *newopt, int newoptlen, | |
710 | int inherit, | |
711 | struct ipv6_opt_hdr **hdr, | |
712 | char **p) | |
713 | { | |
714 | if (inherit) { | |
715 | if (ohdr) { | |
716 | memcpy(*p, ohdr, ipv6_optlen((struct ipv6_opt_hdr *)ohdr)); | |
717 | *hdr = (struct ipv6_opt_hdr *)*p; | |
718 | *p += CMSG_ALIGN(ipv6_optlen(*(struct ipv6_opt_hdr **)hdr)); | |
719 | } | |
720 | } else { | |
721 | if (newopt) { | |
722 | if (copy_from_user(*p, newopt, newoptlen)) | |
723 | return -EFAULT; | |
724 | *hdr = (struct ipv6_opt_hdr *)*p; | |
725 | if (ipv6_optlen(*(struct ipv6_opt_hdr **)hdr) > newoptlen) | |
726 | return -EINVAL; | |
727 | *p += CMSG_ALIGN(newoptlen); | |
728 | } | |
729 | } | |
730 | return 0; | |
731 | } | |
732 | ||
733 | struct ipv6_txoptions * | |
734 | ipv6_renew_options(struct sock *sk, struct ipv6_txoptions *opt, | |
735 | int newtype, | |
736 | struct ipv6_opt_hdr __user *newopt, int newoptlen) | |
737 | { | |
738 | int tot_len = 0; | |
739 | char *p; | |
740 | struct ipv6_txoptions *opt2; | |
741 | int err; | |
742 | ||
99c7bc01 YH |
743 | if (opt) { |
744 | if (newtype != IPV6_HOPOPTS && opt->hopopt) | |
745 | tot_len += CMSG_ALIGN(ipv6_optlen(opt->hopopt)); | |
746 | if (newtype != IPV6_RTHDRDSTOPTS && opt->dst0opt) | |
747 | tot_len += CMSG_ALIGN(ipv6_optlen(opt->dst0opt)); | |
748 | if (newtype != IPV6_RTHDR && opt->srcrt) | |
749 | tot_len += CMSG_ALIGN(ipv6_optlen(opt->srcrt)); | |
750 | if (newtype != IPV6_DSTOPTS && opt->dst1opt) | |
751 | tot_len += CMSG_ALIGN(ipv6_optlen(opt->dst1opt)); | |
752 | } | |
753 | ||
333fad53 YH |
754 | if (newopt && newoptlen) |
755 | tot_len += CMSG_ALIGN(newoptlen); | |
756 | ||
757 | if (!tot_len) | |
758 | return NULL; | |
759 | ||
8b8aa4b5 | 760 | tot_len += sizeof(*opt2); |
333fad53 YH |
761 | opt2 = sock_kmalloc(sk, tot_len, GFP_ATOMIC); |
762 | if (!opt2) | |
763 | return ERR_PTR(-ENOBUFS); | |
764 | ||
765 | memset(opt2, 0, tot_len); | |
766 | ||
767 | opt2->tot_len = tot_len; | |
768 | p = (char *)(opt2 + 1); | |
769 | ||
99c7bc01 | 770 | err = ipv6_renew_option(opt ? opt->hopopt : NULL, newopt, newoptlen, |
333fad53 YH |
771 | newtype != IPV6_HOPOPTS, |
772 | &opt2->hopopt, &p); | |
773 | if (err) | |
774 | goto out; | |
775 | ||
99c7bc01 | 776 | err = ipv6_renew_option(opt ? opt->dst0opt : NULL, newopt, newoptlen, |
333fad53 YH |
777 | newtype != IPV6_RTHDRDSTOPTS, |
778 | &opt2->dst0opt, &p); | |
779 | if (err) | |
780 | goto out; | |
781 | ||
99c7bc01 | 782 | err = ipv6_renew_option(opt ? opt->srcrt : NULL, newopt, newoptlen, |
333fad53 | 783 | newtype != IPV6_RTHDR, |
99c7bc01 | 784 | (struct ipv6_opt_hdr **)&opt2->srcrt, &p); |
333fad53 YH |
785 | if (err) |
786 | goto out; | |
787 | ||
99c7bc01 | 788 | err = ipv6_renew_option(opt ? opt->dst1opt : NULL, newopt, newoptlen, |
333fad53 YH |
789 | newtype != IPV6_DSTOPTS, |
790 | &opt2->dst1opt, &p); | |
791 | if (err) | |
792 | goto out; | |
793 | ||
794 | opt2->opt_nflen = (opt2->hopopt ? ipv6_optlen(opt2->hopopt) : 0) + | |
795 | (opt2->dst0opt ? ipv6_optlen(opt2->dst0opt) : 0) + | |
796 | (opt2->srcrt ? ipv6_optlen(opt2->srcrt) : 0); | |
797 | opt2->opt_flen = (opt2->dst1opt ? ipv6_optlen(opt2->dst1opt) : 0); | |
798 | ||
799 | return opt2; | |
800 | out: | |
8b8aa4b5 | 801 | sock_kfree_s(sk, opt2, opt2->tot_len); |
333fad53 YH |
802 | return ERR_PTR(err); |
803 | } | |
804 | ||
df9890c3 YH |
805 | struct ipv6_txoptions *ipv6_fixup_options(struct ipv6_txoptions *opt_space, |
806 | struct ipv6_txoptions *opt) | |
807 | { | |
808 | /* | |
809 | * ignore the dest before srcrt unless srcrt is being included. | |
810 | * --yoshfuji | |
811 | */ | |
812 | if (opt && opt->dst0opt && !opt->srcrt) { | |
813 | if (opt_space != opt) { | |
814 | memcpy(opt_space, opt, sizeof(*opt_space)); | |
815 | opt = opt_space; | |
816 | } | |
817 | opt->opt_nflen -= ipv6_optlen(opt->dst0opt); | |
818 | opt->dst0opt = NULL; | |
819 | } | |
820 | ||
821 | return opt; | |
822 | } | |
823 |