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: | |
1ab1457c | 19 | * yoshfuji : ensure not to overrun while parsing |
1da177e4 LT |
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> | |
1da177e4 LT |
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> | |
65d4ed92 MN |
45 | #ifdef CONFIG_IPV6_MIP6 |
46 | #include <net/xfrm.h> | |
47 | #endif | |
1da177e4 LT |
48 | |
49 | #include <asm/uaccess.h> | |
50 | ||
c61a4043 MN |
51 | int ipv6_find_tlv(struct sk_buff *skb, int offset, int type) |
52 | { | |
d56f90a7 | 53 | const unsigned char *nh = skb_network_header(skb); |
27a884dc | 54 | int packet_len = skb->tail - skb->network_header; |
c61a4043 MN |
55 | struct ipv6_opt_hdr *hdr; |
56 | int len; | |
57 | ||
58 | if (offset + 2 > packet_len) | |
59 | goto bad; | |
d56f90a7 | 60 | hdr = (struct ipv6_opt_hdr *)(nh + offset); |
c61a4043 MN |
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) { | |
d56f90a7 | 70 | int opttype = nh[offset]; |
c61a4043 MN |
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: | |
d56f90a7 | 81 | optlen = nh[offset + 1] + 2; |
c61a4043 MN |
82 | if (optlen > len) |
83 | goto bad; | |
84 | break; | |
85 | } | |
86 | offset += optlen; | |
87 | len -= optlen; | |
88 | } | |
89 | /* not_found */ | |
c61a4043 MN |
90 | bad: |
91 | return -1; | |
92 | } | |
93 | ||
1da177e4 LT |
94 | /* |
95 | * Parsing tlv encoded headers. | |
96 | * | |
97 | * Parsing function "func" returns 1, if parsing succeed | |
98 | * and 0, if it failed. | |
99 | * It MUST NOT touch skb->h. | |
100 | */ | |
101 | ||
102 | struct tlvtype_proc { | |
103 | int type; | |
a80ff03e | 104 | int (*func)(struct sk_buff **skbp, int offset); |
1da177e4 LT |
105 | }; |
106 | ||
107 | /********************* | |
108 | Generic functions | |
109 | *********************/ | |
110 | ||
111 | /* An unknown option is detected, decide what to do */ | |
112 | ||
a80ff03e | 113 | static int ip6_tlvopt_unknown(struct sk_buff **skbp, int optoff) |
1da177e4 | 114 | { |
a80ff03e MN |
115 | struct sk_buff *skb = *skbp; |
116 | ||
d56f90a7 | 117 | switch ((skb_network_header(skb)[optoff] & 0xC0) >> 6) { |
1da177e4 LT |
118 | case 0: /* ignore */ |
119 | return 1; | |
120 | ||
121 | case 1: /* drop packet */ | |
122 | break; | |
123 | ||
124 | case 3: /* Send ICMP if not a multicast address and drop packet */ | |
125 | /* Actually, it is redundant check. icmp_send | |
126 | will recheck in any case. | |
127 | */ | |
0660e03f | 128 | if (ipv6_addr_is_multicast(&ipv6_hdr(skb)->daddr)) |
1da177e4 LT |
129 | break; |
130 | case 2: /* send ICMP PARM PROB regardless and drop packet */ | |
131 | icmpv6_param_prob(skb, ICMPV6_UNK_OPTION, optoff); | |
132 | return 0; | |
3ff50b79 | 133 | } |
1da177e4 LT |
134 | |
135 | kfree_skb(skb); | |
136 | return 0; | |
137 | } | |
138 | ||
139 | /* Parse tlv encoded option header (hop-by-hop or destination) */ | |
140 | ||
a80ff03e | 141 | static int ip6_parse_tlv(struct tlvtype_proc *procs, struct sk_buff **skbp) |
1da177e4 | 142 | { |
a80ff03e | 143 | struct sk_buff *skb = *skbp; |
1da177e4 | 144 | struct tlvtype_proc *curr; |
d56f90a7 | 145 | const unsigned char *nh = skb_network_header(skb); |
cfe1fc77 | 146 | int off = skb_network_header_len(skb); |
9c70220b | 147 | int len = (skb_transport_header(skb)[1] + 1) << 3; |
1da177e4 | 148 | |
ea2ae17d | 149 | if (skb_transport_offset(skb) + len > skb_headlen(skb)) |
1da177e4 LT |
150 | goto bad; |
151 | ||
152 | off += 2; | |
153 | len -= 2; | |
154 | ||
155 | while (len > 0) { | |
d56f90a7 | 156 | int optlen = nh[off + 1] + 2; |
1da177e4 | 157 | |
d56f90a7 | 158 | switch (nh[off]) { |
1da177e4 LT |
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++) { | |
d56f90a7 | 170 | if (curr->type == nh[off]) { |
1ab1457c YH |
171 | /* type specific length/alignment |
172 | checks will be performed in the | |
1da177e4 | 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 | ||
a831f5bb MN |
199 | #ifdef CONFIG_IPV6_MIP6 |
200 | static int ipv6_dest_hao(struct sk_buff **skbp, int optoff) | |
201 | { | |
202 | struct sk_buff *skb = *skbp; | |
203 | struct ipv6_destopt_hao *hao; | |
204 | struct inet6_skb_parm *opt = IP6CB(skb); | |
0660e03f | 205 | struct ipv6hdr *ipv6h = ipv6_hdr(skb); |
a831f5bb MN |
206 | struct in6_addr tmp_addr; |
207 | int ret; | |
208 | ||
209 | if (opt->dsthao) { | |
210 | LIMIT_NETDEBUG(KERN_DEBUG "hao duplicated\n"); | |
211 | goto discard; | |
212 | } | |
213 | opt->dsthao = opt->dst1; | |
214 | opt->dst1 = 0; | |
215 | ||
d56f90a7 | 216 | hao = (struct ipv6_destopt_hao *)(skb_network_header(skb) + optoff); |
a831f5bb MN |
217 | |
218 | if (hao->length != 16) { | |
219 | LIMIT_NETDEBUG( | |
220 | KERN_DEBUG "hao invalid option length = %d\n", hao->length); | |
221 | goto discard; | |
222 | } | |
223 | ||
224 | if (!(ipv6_addr_type(&hao->addr) & IPV6_ADDR_UNICAST)) { | |
225 | LIMIT_NETDEBUG( | |
226 | KERN_DEBUG "hao is not an unicast addr: " NIP6_FMT "\n", NIP6(hao->addr)); | |
227 | goto discard; | |
228 | } | |
229 | ||
230 | ret = xfrm6_input_addr(skb, (xfrm_address_t *)&ipv6h->daddr, | |
231 | (xfrm_address_t *)&hao->addr, IPPROTO_DSTOPTS); | |
232 | if (unlikely(ret < 0)) | |
233 | goto discard; | |
234 | ||
235 | if (skb_cloned(skb)) { | |
236 | struct sk_buff *skb2 = skb_copy(skb, GFP_ATOMIC); | |
dc435e6d MN |
237 | struct inet6_skb_parm *opt2; |
238 | ||
a831f5bb MN |
239 | if (skb2 == NULL) |
240 | goto discard; | |
241 | ||
dc435e6d MN |
242 | opt2 = IP6CB(skb2); |
243 | memcpy(opt2, opt, sizeof(*opt2)); | |
244 | ||
a831f5bb MN |
245 | kfree_skb(skb); |
246 | ||
247 | /* update all variable using below by copied skbuff */ | |
248 | *skbp = skb = skb2; | |
d56f90a7 ACM |
249 | hao = (struct ipv6_destopt_hao *)(skb_network_header(skb2) + |
250 | optoff); | |
0660e03f | 251 | ipv6h = ipv6_hdr(skb2); |
a831f5bb MN |
252 | } |
253 | ||
254 | if (skb->ip_summed == CHECKSUM_COMPLETE) | |
255 | skb->ip_summed = CHECKSUM_NONE; | |
256 | ||
257 | ipv6_addr_copy(&tmp_addr, &ipv6h->saddr); | |
258 | ipv6_addr_copy(&ipv6h->saddr, &hao->addr); | |
259 | ipv6_addr_copy(&hao->addr, &tmp_addr); | |
260 | ||
b7aa0bf7 | 261 | if (skb->tstamp.tv64 == 0) |
a831f5bb MN |
262 | __net_timestamp(skb); |
263 | ||
264 | return 1; | |
265 | ||
266 | discard: | |
267 | kfree_skb(skb); | |
268 | return 0; | |
269 | } | |
270 | #endif | |
271 | ||
1da177e4 | 272 | static struct tlvtype_proc tlvprocdestopt_lst[] = { |
a831f5bb MN |
273 | #ifdef CONFIG_IPV6_MIP6 |
274 | { | |
275 | .type = IPV6_TLV_HAO, | |
276 | .func = ipv6_dest_hao, | |
277 | }, | |
278 | #endif | |
1da177e4 LT |
279 | {-1, NULL} |
280 | }; | |
281 | ||
951dbc8a | 282 | static int ipv6_destopt_rcv(struct sk_buff **skbp) |
1da177e4 LT |
283 | { |
284 | struct sk_buff *skb = *skbp; | |
285 | struct inet6_skb_parm *opt = IP6CB(skb); | |
a831f5bb MN |
286 | #ifdef CONFIG_IPV6_MIP6 |
287 | __u16 dstbuf; | |
288 | #endif | |
a11d206d | 289 | struct dst_entry *dst; |
1da177e4 | 290 | |
ea2ae17d ACM |
291 | if (!pskb_may_pull(skb, skb_transport_offset(skb) + 8) || |
292 | !pskb_may_pull(skb, (skb_transport_offset(skb) + | |
9c70220b | 293 | ((skb_transport_header(skb)[1] + 1) << 3)))) { |
a11d206d YH |
294 | IP6_INC_STATS_BH(ip6_dst_idev(skb->dst), |
295 | IPSTATS_MIB_INHDRERRORS); | |
1da177e4 LT |
296 | kfree_skb(skb); |
297 | return -1; | |
298 | } | |
299 | ||
cfe1fc77 | 300 | opt->lastopt = opt->dst1 = skb_network_header_len(skb); |
a831f5bb MN |
301 | #ifdef CONFIG_IPV6_MIP6 |
302 | dstbuf = opt->dst1; | |
303 | #endif | |
1da177e4 | 304 | |
a11d206d | 305 | dst = dst_clone(skb->dst); |
a80ff03e | 306 | if (ip6_parse_tlv(tlvprocdestopt_lst, skbp)) { |
a11d206d | 307 | dst_release(dst); |
a80ff03e | 308 | skb = *skbp; |
b0e380b1 | 309 | skb->transport_header += (skb_transport_header(skb)[1] + 1) << 3; |
dc435e6d | 310 | opt = IP6CB(skb); |
a831f5bb MN |
311 | #ifdef CONFIG_IPV6_MIP6 |
312 | opt->nhoff = dstbuf; | |
313 | #else | |
951dbc8a | 314 | opt->nhoff = opt->dst1; |
a831f5bb | 315 | #endif |
1da177e4 LT |
316 | return 1; |
317 | } | |
318 | ||
a11d206d YH |
319 | IP6_INC_STATS_BH(ip6_dst_idev(dst), IPSTATS_MIB_INHDRERRORS); |
320 | dst_release(dst); | |
1da177e4 LT |
321 | return -1; |
322 | } | |
323 | ||
324 | static struct inet6_protocol destopt_protocol = { | |
325 | .handler = ipv6_destopt_rcv, | |
adcfc7d0 | 326 | .flags = INET6_PROTO_NOPOLICY | INET6_PROTO_GSO_EXTHDR, |
1da177e4 LT |
327 | }; |
328 | ||
329 | void __init ipv6_destopt_init(void) | |
330 | { | |
331 | if (inet6_add_protocol(&destopt_protocol, IPPROTO_DSTOPTS) < 0) | |
332 | printk(KERN_ERR "ipv6_destopt_init: Could not register protocol\n"); | |
333 | } | |
334 | ||
335 | /******************************** | |
336 | NONE header. No data in packet. | |
337 | ********************************/ | |
338 | ||
951dbc8a | 339 | static int ipv6_nodata_rcv(struct sk_buff **skbp) |
1da177e4 LT |
340 | { |
341 | struct sk_buff *skb = *skbp; | |
342 | ||
343 | kfree_skb(skb); | |
344 | return 0; | |
345 | } | |
346 | ||
347 | static struct inet6_protocol nodata_protocol = { | |
348 | .handler = ipv6_nodata_rcv, | |
349 | .flags = INET6_PROTO_NOPOLICY, | |
350 | }; | |
351 | ||
352 | void __init ipv6_nodata_init(void) | |
353 | { | |
354 | if (inet6_add_protocol(&nodata_protocol, IPPROTO_NONE) < 0) | |
355 | printk(KERN_ERR "ipv6_nodata_init: Could not register protocol\n"); | |
356 | } | |
357 | ||
358 | /******************************** | |
359 | Routing header. | |
360 | ********************************/ | |
361 | ||
951dbc8a | 362 | static int ipv6_rthdr_rcv(struct sk_buff **skbp) |
1da177e4 LT |
363 | { |
364 | struct sk_buff *skb = *skbp; | |
365 | struct inet6_skb_parm *opt = IP6CB(skb); | |
65d4ed92 | 366 | struct in6_addr *addr = NULL; |
1da177e4 | 367 | struct in6_addr daddr; |
0bcbc926 | 368 | struct inet6_dev *idev; |
1da177e4 | 369 | int n, i; |
1da177e4 LT |
370 | struct ipv6_rt_hdr *hdr; |
371 | struct rt0_hdr *rthdr; | |
0bcbc926 YH |
372 | int accept_source_route = ipv6_devconf.accept_source_route; |
373 | ||
374 | if (accept_source_route < 0 || | |
375 | ((idev = in6_dev_get(skb->dev)) == NULL)) { | |
376 | kfree_skb(skb); | |
377 | return -1; | |
378 | } | |
379 | if (idev->cnf.accept_source_route < 0) { | |
380 | in6_dev_put(idev); | |
381 | kfree_skb(skb); | |
382 | return -1; | |
383 | } | |
384 | ||
385 | if (accept_source_route > idev->cnf.accept_source_route) | |
386 | accept_source_route = idev->cnf.accept_source_route; | |
387 | ||
388 | in6_dev_put(idev); | |
1da177e4 | 389 | |
ea2ae17d ACM |
390 | if (!pskb_may_pull(skb, skb_transport_offset(skb) + 8) || |
391 | !pskb_may_pull(skb, (skb_transport_offset(skb) + | |
9c70220b | 392 | ((skb_transport_header(skb)[1] + 1) << 3)))) { |
a11d206d YH |
393 | IP6_INC_STATS_BH(ip6_dst_idev(skb->dst), |
394 | IPSTATS_MIB_INHDRERRORS); | |
1da177e4 LT |
395 | kfree_skb(skb); |
396 | return -1; | |
397 | } | |
398 | ||
9c70220b | 399 | hdr = (struct ipv6_rt_hdr *)skb_transport_header(skb); |
1da177e4 | 400 | |
0bcbc926 YH |
401 | switch (hdr->type) { |
402 | #ifdef CONFIG_IPV6_MIP6 | |
ebbd90a7 | 403 | case IPV6_SRCRT_TYPE_2: |
0bcbc926 YH |
404 | break; |
405 | #endif | |
406 | case IPV6_SRCRT_TYPE_0: | |
a23cf14b | 407 | if (accept_source_route > 0) |
0bcbc926 YH |
408 | break; |
409 | kfree_skb(skb); | |
410 | return -1; | |
411 | default: | |
412 | IP6_INC_STATS_BH(ip6_dst_idev(skb->dst), | |
413 | IPSTATS_MIB_INHDRERRORS); | |
d56f90a7 ACM |
414 | icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, |
415 | (&hdr->type) - skb_network_header(skb)); | |
0bcbc926 YH |
416 | return -1; |
417 | } | |
418 | ||
0660e03f | 419 | if (ipv6_addr_is_multicast(&ipv6_hdr(skb)->daddr) || |
1da177e4 | 420 | skb->pkt_type != PACKET_HOST) { |
a11d206d YH |
421 | IP6_INC_STATS_BH(ip6_dst_idev(skb->dst), |
422 | IPSTATS_MIB_INADDRERRORS); | |
1da177e4 LT |
423 | kfree_skb(skb); |
424 | return -1; | |
425 | } | |
426 | ||
427 | looped_back: | |
428 | if (hdr->segments_left == 0) { | |
65d4ed92 MN |
429 | switch (hdr->type) { |
430 | #ifdef CONFIG_IPV6_MIP6 | |
431 | case IPV6_SRCRT_TYPE_2: | |
432 | /* Silently discard type 2 header unless it was | |
433 | * processed by own | |
434 | */ | |
435 | if (!addr) { | |
a11d206d YH |
436 | IP6_INC_STATS_BH(ip6_dst_idev(skb->dst), |
437 | IPSTATS_MIB_INADDRERRORS); | |
65d4ed92 MN |
438 | kfree_skb(skb); |
439 | return -1; | |
440 | } | |
441 | break; | |
442 | #endif | |
443 | default: | |
444 | break; | |
445 | } | |
446 | ||
cfe1fc77 | 447 | opt->lastopt = opt->srcrt = skb_network_header_len(skb); |
b0e380b1 | 448 | skb->transport_header += (hdr->hdrlen + 1) << 3; |
1da177e4 LT |
449 | opt->dst0 = opt->dst1; |
450 | opt->dst1 = 0; | |
d56f90a7 | 451 | opt->nhoff = (&hdr->nexthdr) - skb_network_header(skb); |
1da177e4 LT |
452 | return 1; |
453 | } | |
454 | ||
65d4ed92 MN |
455 | switch (hdr->type) { |
456 | case IPV6_SRCRT_TYPE_0: | |
457 | if (hdr->hdrlen & 0x01) { | |
a11d206d YH |
458 | IP6_INC_STATS_BH(ip6_dst_idev(skb->dst), |
459 | IPSTATS_MIB_INHDRERRORS); | |
d56f90a7 ACM |
460 | icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, |
461 | ((&hdr->hdrlen) - | |
462 | skb_network_header(skb))); | |
65d4ed92 MN |
463 | return -1; |
464 | } | |
465 | break; | |
466 | #ifdef CONFIG_IPV6_MIP6 | |
467 | case IPV6_SRCRT_TYPE_2: | |
468 | /* Silently discard invalid RTH type 2 */ | |
469 | if (hdr->hdrlen != 2 || hdr->segments_left != 1) { | |
a11d206d YH |
470 | IP6_INC_STATS_BH(ip6_dst_idev(skb->dst), |
471 | IPSTATS_MIB_INHDRERRORS); | |
65d4ed92 MN |
472 | kfree_skb(skb); |
473 | return -1; | |
474 | } | |
475 | break; | |
476 | #endif | |
1da177e4 | 477 | } |
1da177e4 LT |
478 | |
479 | /* | |
480 | * This is the routing header forwarding algorithm from | |
481 | * RFC 2460, page 16. | |
482 | */ | |
483 | ||
484 | n = hdr->hdrlen >> 1; | |
485 | ||
486 | if (hdr->segments_left > n) { | |
a11d206d YH |
487 | IP6_INC_STATS_BH(ip6_dst_idev(skb->dst), |
488 | IPSTATS_MIB_INHDRERRORS); | |
d56f90a7 ACM |
489 | icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, |
490 | ((&hdr->segments_left) - | |
491 | skb_network_header(skb))); | |
1da177e4 LT |
492 | return -1; |
493 | } | |
494 | ||
495 | /* We are about to mangle packet header. Be careful! | |
496 | Do not damage packets queued somewhere. | |
497 | */ | |
498 | if (skb_cloned(skb)) { | |
499 | struct sk_buff *skb2 = skb_copy(skb, GFP_ATOMIC); | |
1da177e4 LT |
500 | /* the copy is a forwarded packet */ |
501 | if (skb2 == NULL) { | |
a11d206d YH |
502 | IP6_INC_STATS_BH(ip6_dst_idev(skb->dst), |
503 | IPSTATS_MIB_OUTDISCARDS); | |
504 | kfree_skb(skb); | |
1da177e4 LT |
505 | return -1; |
506 | } | |
a11d206d | 507 | kfree_skb(skb); |
1da177e4 LT |
508 | *skbp = skb = skb2; |
509 | opt = IP6CB(skb2); | |
bff9b61c | 510 | hdr = (struct ipv6_rt_hdr *)skb_transport_header(skb2); |
1da177e4 LT |
511 | } |
512 | ||
84fa7933 | 513 | if (skb->ip_summed == CHECKSUM_COMPLETE) |
1da177e4 LT |
514 | skb->ip_summed = CHECKSUM_NONE; |
515 | ||
516 | i = n - --hdr->segments_left; | |
517 | ||
518 | rthdr = (struct rt0_hdr *) hdr; | |
519 | addr = rthdr->addr; | |
520 | addr += i - 1; | |
521 | ||
65d4ed92 MN |
522 | switch (hdr->type) { |
523 | #ifdef CONFIG_IPV6_MIP6 | |
524 | case IPV6_SRCRT_TYPE_2: | |
525 | if (xfrm6_input_addr(skb, (xfrm_address_t *)addr, | |
0660e03f | 526 | (xfrm_address_t *)&ipv6_hdr(skb)->saddr, |
65d4ed92 | 527 | IPPROTO_ROUTING) < 0) { |
a11d206d YH |
528 | IP6_INC_STATS_BH(ip6_dst_idev(skb->dst), |
529 | IPSTATS_MIB_INADDRERRORS); | |
65d4ed92 MN |
530 | kfree_skb(skb); |
531 | return -1; | |
532 | } | |
533 | if (!ipv6_chk_home_addr(addr)) { | |
a11d206d YH |
534 | IP6_INC_STATS_BH(ip6_dst_idev(skb->dst), |
535 | IPSTATS_MIB_INADDRERRORS); | |
65d4ed92 MN |
536 | kfree_skb(skb); |
537 | return -1; | |
538 | } | |
539 | break; | |
540 | #endif | |
541 | default: | |
542 | break; | |
543 | } | |
544 | ||
1da177e4 | 545 | if (ipv6_addr_is_multicast(addr)) { |
a11d206d YH |
546 | IP6_INC_STATS_BH(ip6_dst_idev(skb->dst), |
547 | IPSTATS_MIB_INADDRERRORS); | |
1da177e4 LT |
548 | kfree_skb(skb); |
549 | return -1; | |
550 | } | |
551 | ||
552 | ipv6_addr_copy(&daddr, addr); | |
0660e03f ACM |
553 | ipv6_addr_copy(addr, &ipv6_hdr(skb)->daddr); |
554 | ipv6_addr_copy(&ipv6_hdr(skb)->daddr, &daddr); | |
1da177e4 LT |
555 | |
556 | dst_release(xchg(&skb->dst, NULL)); | |
557 | ip6_route_input(skb); | |
558 | if (skb->dst->error) { | |
d56f90a7 | 559 | skb_push(skb, skb->data - skb_network_header(skb)); |
1da177e4 LT |
560 | dst_input(skb); |
561 | return -1; | |
562 | } | |
563 | ||
564 | if (skb->dst->dev->flags&IFF_LOOPBACK) { | |
0660e03f | 565 | if (ipv6_hdr(skb)->hop_limit <= 1) { |
a11d206d YH |
566 | IP6_INC_STATS_BH(ip6_dst_idev(skb->dst), |
567 | IPSTATS_MIB_INHDRERRORS); | |
1da177e4 LT |
568 | icmpv6_send(skb, ICMPV6_TIME_EXCEED, ICMPV6_EXC_HOPLIMIT, |
569 | 0, skb->dev); | |
570 | kfree_skb(skb); | |
571 | return -1; | |
572 | } | |
0660e03f | 573 | ipv6_hdr(skb)->hop_limit--; |
1da177e4 LT |
574 | goto looped_back; |
575 | } | |
576 | ||
d56f90a7 | 577 | skb_push(skb, skb->data - skb_network_header(skb)); |
1da177e4 LT |
578 | dst_input(skb); |
579 | return -1; | |
580 | } | |
581 | ||
582 | static struct inet6_protocol rthdr_protocol = { | |
583 | .handler = ipv6_rthdr_rcv, | |
adcfc7d0 | 584 | .flags = INET6_PROTO_NOPOLICY | INET6_PROTO_GSO_EXTHDR, |
1da177e4 LT |
585 | }; |
586 | ||
587 | void __init ipv6_rthdr_init(void) | |
588 | { | |
589 | if (inet6_add_protocol(&rthdr_protocol, IPPROTO_ROUTING) < 0) | |
590 | printk(KERN_ERR "ipv6_rthdr_init: Could not register protocol\n"); | |
591 | }; | |
592 | ||
593 | /* | |
594 | This function inverts received rthdr. | |
595 | NOTE: specs allow to make it automatically only if | |
596 | packet authenticated. | |
597 | ||
598 | I will not discuss it here (though, I am really pissed off at | |
599 | this stupid requirement making rthdr idea useless) | |
600 | ||
601 | Actually, it creates severe problems for us. | |
602 | Embryonic requests has no associated sockets, | |
603 | so that user have no control over it and | |
604 | cannot not only to set reply options, but | |
605 | even to know, that someone wants to connect | |
606 | without success. :-( | |
607 | ||
608 | For now we need to test the engine, so that I created | |
609 | temporary (or permanent) backdoor. | |
610 | If listening socket set IPV6_RTHDR to 2, then we invert header. | |
1ab1457c | 611 | --ANK (980729) |
1da177e4 LT |
612 | */ |
613 | ||
614 | struct ipv6_txoptions * | |
615 | ipv6_invert_rthdr(struct sock *sk, struct ipv6_rt_hdr *hdr) | |
616 | { | |
617 | /* Received rthdr: | |
618 | ||
619 | [ H1 -> H2 -> ... H_prev ] daddr=ME | |
620 | ||
621 | Inverted result: | |
622 | [ H_prev -> ... -> H1 ] daddr =sender | |
623 | ||
624 | Note, that IP output engine will rewrite this rthdr | |
625 | by rotating it left by one addr. | |
626 | */ | |
627 | ||
628 | int n, i; | |
629 | struct rt0_hdr *rthdr = (struct rt0_hdr*)hdr; | |
630 | struct rt0_hdr *irthdr; | |
631 | struct ipv6_txoptions *opt; | |
632 | int hdrlen = ipv6_optlen(hdr); | |
633 | ||
634 | if (hdr->segments_left || | |
635 | hdr->type != IPV6_SRCRT_TYPE_0 || | |
636 | hdr->hdrlen & 0x01) | |
637 | return NULL; | |
638 | ||
639 | n = hdr->hdrlen >> 1; | |
640 | opt = sock_kmalloc(sk, sizeof(*opt) + hdrlen, GFP_ATOMIC); | |
641 | if (opt == NULL) | |
642 | return NULL; | |
643 | memset(opt, 0, sizeof(*opt)); | |
644 | opt->tot_len = sizeof(*opt) + hdrlen; | |
645 | opt->srcrt = (void*)(opt+1); | |
646 | opt->opt_nflen = hdrlen; | |
647 | ||
648 | memcpy(opt->srcrt, hdr, sizeof(*hdr)); | |
649 | irthdr = (struct rt0_hdr*)opt->srcrt; | |
e6df439b | 650 | irthdr->reserved = 0; |
1da177e4 LT |
651 | opt->srcrt->segments_left = n; |
652 | for (i=0; i<n; i++) | |
653 | memcpy(irthdr->addr+i, rthdr->addr+(n-1-i), 16); | |
654 | return opt; | |
655 | } | |
656 | ||
3cf3dc6c ACM |
657 | EXPORT_SYMBOL_GPL(ipv6_invert_rthdr); |
658 | ||
1da177e4 LT |
659 | /********************************** |
660 | Hop-by-hop options. | |
661 | **********************************/ | |
662 | ||
e76b2b25 YH |
663 | /* |
664 | * Note: we cannot rely on skb->dst before we assign it in ip6_route_input(). | |
665 | */ | |
666 | static inline struct inet6_dev *ipv6_skb_idev(struct sk_buff *skb) | |
667 | { | |
668 | return skb->dst ? ip6_dst_idev(skb->dst) : __in6_dev_get(skb->dev); | |
669 | } | |
670 | ||
1da177e4 LT |
671 | /* Router Alert as of RFC 2711 */ |
672 | ||
a80ff03e | 673 | static int ipv6_hop_ra(struct sk_buff **skbp, int optoff) |
1da177e4 | 674 | { |
a80ff03e | 675 | struct sk_buff *skb = *skbp; |
d56f90a7 | 676 | const unsigned char *nh = skb_network_header(skb); |
a80ff03e | 677 | |
d56f90a7 | 678 | if (nh[optoff + 1] == 2) { |
1da177e4 LT |
679 | IP6CB(skb)->ra = optoff; |
680 | return 1; | |
681 | } | |
64ce2073 | 682 | LIMIT_NETDEBUG(KERN_DEBUG "ipv6_hop_ra: wrong RA length %d\n", |
d56f90a7 | 683 | nh[optoff + 1]); |
1da177e4 LT |
684 | kfree_skb(skb); |
685 | return 0; | |
686 | } | |
687 | ||
688 | /* Jumbo payload */ | |
689 | ||
a80ff03e | 690 | static int ipv6_hop_jumbo(struct sk_buff **skbp, int optoff) |
1da177e4 | 691 | { |
a80ff03e | 692 | struct sk_buff *skb = *skbp; |
d56f90a7 | 693 | const unsigned char *nh = skb_network_header(skb); |
1da177e4 LT |
694 | u32 pkt_len; |
695 | ||
d56f90a7 | 696 | if (nh[optoff + 1] != 4 || (optoff & 3) != 2) { |
64ce2073 | 697 | LIMIT_NETDEBUG(KERN_DEBUG "ipv6_hop_jumbo: wrong jumbo opt length/alignment %d\n", |
d56f90a7 | 698 | nh[optoff+1]); |
e76b2b25 | 699 | IP6_INC_STATS_BH(ipv6_skb_idev(skb), |
a11d206d | 700 | IPSTATS_MIB_INHDRERRORS); |
1da177e4 LT |
701 | goto drop; |
702 | } | |
703 | ||
d56f90a7 | 704 | pkt_len = ntohl(*(__be32 *)(nh + optoff + 2)); |
1da177e4 | 705 | if (pkt_len <= IPV6_MAXPLEN) { |
e76b2b25 | 706 | IP6_INC_STATS_BH(ipv6_skb_idev(skb), IPSTATS_MIB_INHDRERRORS); |
1da177e4 LT |
707 | icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, optoff+2); |
708 | return 0; | |
709 | } | |
0660e03f | 710 | if (ipv6_hdr(skb)->payload_len) { |
e76b2b25 | 711 | IP6_INC_STATS_BH(ipv6_skb_idev(skb), IPSTATS_MIB_INHDRERRORS); |
1da177e4 LT |
712 | icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, optoff); |
713 | return 0; | |
714 | } | |
715 | ||
716 | if (pkt_len > skb->len - sizeof(struct ipv6hdr)) { | |
e76b2b25 | 717 | IP6_INC_STATS_BH(ipv6_skb_idev(skb), IPSTATS_MIB_INTRUNCATEDPKTS); |
1da177e4 LT |
718 | goto drop; |
719 | } | |
42ca89c1 SH |
720 | |
721 | if (pskb_trim_rcsum(skb, pkt_len + sizeof(struct ipv6hdr))) | |
722 | goto drop; | |
723 | ||
1da177e4 LT |
724 | return 1; |
725 | ||
726 | drop: | |
727 | kfree_skb(skb); | |
728 | return 0; | |
729 | } | |
730 | ||
731 | static struct tlvtype_proc tlvprochopopt_lst[] = { | |
732 | { | |
733 | .type = IPV6_TLV_ROUTERALERT, | |
734 | .func = ipv6_hop_ra, | |
735 | }, | |
736 | { | |
737 | .type = IPV6_TLV_JUMBO, | |
738 | .func = ipv6_hop_jumbo, | |
739 | }, | |
740 | { -1, } | |
741 | }; | |
742 | ||
a80ff03e | 743 | int ipv6_parse_hopopts(struct sk_buff **skbp) |
1da177e4 | 744 | { |
a80ff03e | 745 | struct sk_buff *skb = *skbp; |
951dbc8a PM |
746 | struct inet6_skb_parm *opt = IP6CB(skb); |
747 | ||
ec670095 | 748 | /* |
d56f90a7 | 749 | * skb_network_header(skb) is equal to skb->data, and |
cfe1fc77 | 750 | * skb_network_header_len(skb) is always equal to |
ec670095 YH |
751 | * sizeof(struct ipv6hdr) by definition of |
752 | * hop-by-hop options. | |
753 | */ | |
754 | if (!pskb_may_pull(skb, sizeof(struct ipv6hdr) + 8) || | |
9c70220b ACM |
755 | !pskb_may_pull(skb, (sizeof(struct ipv6hdr) + |
756 | ((skb_transport_header(skb)[1] + 1) << 3)))) { | |
ec670095 YH |
757 | kfree_skb(skb); |
758 | return -1; | |
759 | } | |
760 | ||
951dbc8a | 761 | opt->hop = sizeof(struct ipv6hdr); |
a80ff03e MN |
762 | if (ip6_parse_tlv(tlvprochopopt_lst, skbp)) { |
763 | skb = *skbp; | |
b0e380b1 | 764 | skb->transport_header += (skb_transport_header(skb)[1] + 1) << 3; |
dc435e6d | 765 | opt = IP6CB(skb); |
951dbc8a | 766 | opt->nhoff = sizeof(struct ipv6hdr); |
b809739a | 767 | return 1; |
951dbc8a | 768 | } |
1da177e4 LT |
769 | return -1; |
770 | } | |
771 | ||
772 | /* | |
773 | * Creating outbound headers. | |
774 | * | |
775 | * "build" functions work when skb is filled from head to tail (datagram) | |
776 | * "push" functions work when headers are added from tail to head (tcp) | |
777 | * | |
778 | * In both cases we assume, that caller reserved enough room | |
779 | * for headers. | |
780 | */ | |
781 | ||
782 | static void ipv6_push_rthdr(struct sk_buff *skb, u8 *proto, | |
783 | struct ipv6_rt_hdr *opt, | |
784 | struct in6_addr **addr_p) | |
785 | { | |
786 | struct rt0_hdr *phdr, *ihdr; | |
787 | int hops; | |
788 | ||
789 | ihdr = (struct rt0_hdr *) opt; | |
1ab1457c | 790 | |
1da177e4 LT |
791 | phdr = (struct rt0_hdr *) skb_push(skb, (ihdr->rt_hdr.hdrlen + 1) << 3); |
792 | memcpy(phdr, ihdr, sizeof(struct rt0_hdr)); | |
793 | ||
794 | hops = ihdr->rt_hdr.hdrlen >> 1; | |
795 | ||
796 | if (hops > 1) | |
797 | memcpy(phdr->addr, ihdr->addr + 1, | |
798 | (hops - 1) * sizeof(struct in6_addr)); | |
799 | ||
800 | ipv6_addr_copy(phdr->addr + (hops - 1), *addr_p); | |
801 | *addr_p = ihdr->addr; | |
802 | ||
803 | phdr->rt_hdr.nexthdr = *proto; | |
804 | *proto = NEXTHDR_ROUTING; | |
805 | } | |
806 | ||
807 | static void ipv6_push_exthdr(struct sk_buff *skb, u8 *proto, u8 type, struct ipv6_opt_hdr *opt) | |
808 | { | |
809 | struct ipv6_opt_hdr *h = (struct ipv6_opt_hdr *)skb_push(skb, ipv6_optlen(opt)); | |
810 | ||
811 | memcpy(h, opt, ipv6_optlen(opt)); | |
812 | h->nexthdr = *proto; | |
813 | *proto = type; | |
814 | } | |
815 | ||
816 | void ipv6_push_nfrag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt, | |
817 | u8 *proto, | |
818 | struct in6_addr **daddr) | |
819 | { | |
333fad53 | 820 | if (opt->srcrt) { |
1da177e4 | 821 | ipv6_push_rthdr(skb, proto, opt->srcrt, daddr); |
333fad53 YH |
822 | /* |
823 | * IPV6_RTHDRDSTOPTS is ignored | |
824 | * unless IPV6_RTHDR is set (RFC3542). | |
825 | */ | |
826 | if (opt->dst0opt) | |
827 | ipv6_push_exthdr(skb, proto, NEXTHDR_DEST, opt->dst0opt); | |
828 | } | |
1da177e4 LT |
829 | if (opt->hopopt) |
830 | ipv6_push_exthdr(skb, proto, NEXTHDR_HOP, opt->hopopt); | |
831 | } | |
832 | ||
7159039a YH |
833 | EXPORT_SYMBOL(ipv6_push_nfrag_opts); |
834 | ||
1da177e4 LT |
835 | void ipv6_push_frag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt, u8 *proto) |
836 | { | |
837 | if (opt->dst1opt) | |
838 | ipv6_push_exthdr(skb, proto, NEXTHDR_DEST, opt->dst1opt); | |
839 | } | |
840 | ||
841 | struct ipv6_txoptions * | |
842 | ipv6_dup_options(struct sock *sk, struct ipv6_txoptions *opt) | |
843 | { | |
844 | struct ipv6_txoptions *opt2; | |
845 | ||
846 | opt2 = sock_kmalloc(sk, opt->tot_len, GFP_ATOMIC); | |
847 | if (opt2) { | |
848 | long dif = (char*)opt2 - (char*)opt; | |
849 | memcpy(opt2, opt, opt->tot_len); | |
850 | if (opt2->hopopt) | |
851 | *((char**)&opt2->hopopt) += dif; | |
852 | if (opt2->dst0opt) | |
853 | *((char**)&opt2->dst0opt) += dif; | |
854 | if (opt2->dst1opt) | |
855 | *((char**)&opt2->dst1opt) += dif; | |
856 | if (opt2->srcrt) | |
857 | *((char**)&opt2->srcrt) += dif; | |
858 | } | |
859 | return opt2; | |
860 | } | |
333fad53 | 861 | |
3cf3dc6c ACM |
862 | EXPORT_SYMBOL_GPL(ipv6_dup_options); |
863 | ||
333fad53 YH |
864 | static int ipv6_renew_option(void *ohdr, |
865 | struct ipv6_opt_hdr __user *newopt, int newoptlen, | |
866 | int inherit, | |
867 | struct ipv6_opt_hdr **hdr, | |
868 | char **p) | |
869 | { | |
870 | if (inherit) { | |
871 | if (ohdr) { | |
872 | memcpy(*p, ohdr, ipv6_optlen((struct ipv6_opt_hdr *)ohdr)); | |
873 | *hdr = (struct ipv6_opt_hdr *)*p; | |
874 | *p += CMSG_ALIGN(ipv6_optlen(*(struct ipv6_opt_hdr **)hdr)); | |
875 | } | |
876 | } else { | |
877 | if (newopt) { | |
878 | if (copy_from_user(*p, newopt, newoptlen)) | |
879 | return -EFAULT; | |
880 | *hdr = (struct ipv6_opt_hdr *)*p; | |
881 | if (ipv6_optlen(*(struct ipv6_opt_hdr **)hdr) > newoptlen) | |
882 | return -EINVAL; | |
883 | *p += CMSG_ALIGN(newoptlen); | |
884 | } | |
885 | } | |
886 | return 0; | |
887 | } | |
888 | ||
889 | struct ipv6_txoptions * | |
890 | ipv6_renew_options(struct sock *sk, struct ipv6_txoptions *opt, | |
891 | int newtype, | |
892 | struct ipv6_opt_hdr __user *newopt, int newoptlen) | |
893 | { | |
894 | int tot_len = 0; | |
895 | char *p; | |
896 | struct ipv6_txoptions *opt2; | |
897 | int err; | |
898 | ||
99c7bc01 YH |
899 | if (opt) { |
900 | if (newtype != IPV6_HOPOPTS && opt->hopopt) | |
901 | tot_len += CMSG_ALIGN(ipv6_optlen(opt->hopopt)); | |
902 | if (newtype != IPV6_RTHDRDSTOPTS && opt->dst0opt) | |
903 | tot_len += CMSG_ALIGN(ipv6_optlen(opt->dst0opt)); | |
904 | if (newtype != IPV6_RTHDR && opt->srcrt) | |
905 | tot_len += CMSG_ALIGN(ipv6_optlen(opt->srcrt)); | |
906 | if (newtype != IPV6_DSTOPTS && opt->dst1opt) | |
907 | tot_len += CMSG_ALIGN(ipv6_optlen(opt->dst1opt)); | |
908 | } | |
909 | ||
333fad53 YH |
910 | if (newopt && newoptlen) |
911 | tot_len += CMSG_ALIGN(newoptlen); | |
912 | ||
913 | if (!tot_len) | |
914 | return NULL; | |
915 | ||
8b8aa4b5 | 916 | tot_len += sizeof(*opt2); |
333fad53 YH |
917 | opt2 = sock_kmalloc(sk, tot_len, GFP_ATOMIC); |
918 | if (!opt2) | |
919 | return ERR_PTR(-ENOBUFS); | |
920 | ||
921 | memset(opt2, 0, tot_len); | |
922 | ||
923 | opt2->tot_len = tot_len; | |
924 | p = (char *)(opt2 + 1); | |
925 | ||
99c7bc01 | 926 | err = ipv6_renew_option(opt ? opt->hopopt : NULL, newopt, newoptlen, |
333fad53 YH |
927 | newtype != IPV6_HOPOPTS, |
928 | &opt2->hopopt, &p); | |
929 | if (err) | |
930 | goto out; | |
931 | ||
99c7bc01 | 932 | err = ipv6_renew_option(opt ? opt->dst0opt : NULL, newopt, newoptlen, |
333fad53 YH |
933 | newtype != IPV6_RTHDRDSTOPTS, |
934 | &opt2->dst0opt, &p); | |
935 | if (err) | |
936 | goto out; | |
937 | ||
99c7bc01 | 938 | err = ipv6_renew_option(opt ? opt->srcrt : NULL, newopt, newoptlen, |
333fad53 | 939 | newtype != IPV6_RTHDR, |
99c7bc01 | 940 | (struct ipv6_opt_hdr **)&opt2->srcrt, &p); |
333fad53 YH |
941 | if (err) |
942 | goto out; | |
943 | ||
99c7bc01 | 944 | err = ipv6_renew_option(opt ? opt->dst1opt : NULL, newopt, newoptlen, |
333fad53 YH |
945 | newtype != IPV6_DSTOPTS, |
946 | &opt2->dst1opt, &p); | |
947 | if (err) | |
948 | goto out; | |
949 | ||
950 | opt2->opt_nflen = (opt2->hopopt ? ipv6_optlen(opt2->hopopt) : 0) + | |
951 | (opt2->dst0opt ? ipv6_optlen(opt2->dst0opt) : 0) + | |
952 | (opt2->srcrt ? ipv6_optlen(opt2->srcrt) : 0); | |
953 | opt2->opt_flen = (opt2->dst1opt ? ipv6_optlen(opt2->dst1opt) : 0); | |
954 | ||
955 | return opt2; | |
956 | out: | |
8b8aa4b5 | 957 | sock_kfree_s(sk, opt2, opt2->tot_len); |
333fad53 YH |
958 | return ERR_PTR(err); |
959 | } | |
960 | ||
df9890c3 YH |
961 | struct ipv6_txoptions *ipv6_fixup_options(struct ipv6_txoptions *opt_space, |
962 | struct ipv6_txoptions *opt) | |
963 | { | |
964 | /* | |
965 | * ignore the dest before srcrt unless srcrt is being included. | |
966 | * --yoshfuji | |
967 | */ | |
968 | if (opt && opt->dst0opt && !opt->srcrt) { | |
969 | if (opt_space != opt) { | |
970 | memcpy(opt_space, opt, sizeof(*opt_space)); | |
971 | opt = opt_space; | |
972 | } | |
973 | opt->opt_nflen -= ipv6_optlen(opt->dst0opt); | |
974 | opt->dst0opt = NULL; | |
975 | } | |
976 | ||
977 | return opt; | |
978 | } | |
979 |