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Commit | Line | Data |
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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 | * | |
1da177e4 LT |
10 | * This program is free software; you can redistribute it and/or |
11 | * modify it under the terms of the GNU General Public License | |
12 | * as published by the Free Software Foundation; either version | |
13 | * 2 of the License, or (at your option) any later version. | |
14 | */ | |
15 | ||
16 | /* Changes: | |
1ab1457c | 17 | * yoshfuji : ensure not to overrun while parsing |
1da177e4 LT |
18 | * tlv options. |
19 | * Mitsuru KANDA @USAGI and: Remove ipv6_parse_exthdrs(). | |
20 | * YOSHIFUJI Hideaki @USAGI Register inbound extension header | |
21 | * handlers as inet6_protocol{}. | |
22 | */ | |
23 | ||
24 | #include <linux/errno.h> | |
25 | #include <linux/types.h> | |
26 | #include <linux/socket.h> | |
27 | #include <linux/sockios.h> | |
1da177e4 LT |
28 | #include <linux/net.h> |
29 | #include <linux/netdevice.h> | |
30 | #include <linux/in6.h> | |
31 | #include <linux/icmpv6.h> | |
32 | ||
352e512c | 33 | #include <net/dst.h> |
1da177e4 LT |
34 | #include <net/sock.h> |
35 | #include <net/snmp.h> | |
36 | ||
37 | #include <net/ipv6.h> | |
38 | #include <net/protocol.h> | |
39 | #include <net/transp_v6.h> | |
40 | #include <net/rawv6.h> | |
41 | #include <net/ndisc.h> | |
42 | #include <net/ip6_route.h> | |
43 | #include <net/addrconf.h> | |
59fbb3a6 | 44 | #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE) |
65d4ed92 MN |
45 | #include <net/xfrm.h> |
46 | #endif | |
1da177e4 LT |
47 | |
48 | #include <asm/uaccess.h> | |
49 | ||
c61a4043 MN |
50 | int ipv6_find_tlv(struct sk_buff *skb, int offset, int type) |
51 | { | |
d56f90a7 | 52 | const unsigned char *nh = skb_network_header(skb); |
27a884dc | 53 | int packet_len = skb->tail - skb->network_header; |
c61a4043 MN |
54 | struct ipv6_opt_hdr *hdr; |
55 | int len; | |
56 | ||
57 | if (offset + 2 > packet_len) | |
58 | goto bad; | |
d56f90a7 | 59 | hdr = (struct ipv6_opt_hdr *)(nh + offset); |
c61a4043 MN |
60 | len = ((hdr->hdrlen + 1) << 3); |
61 | ||
62 | if (offset + len > packet_len) | |
63 | goto bad; | |
64 | ||
65 | offset += 2; | |
66 | len -= 2; | |
67 | ||
68 | while (len > 0) { | |
d56f90a7 | 69 | int opttype = nh[offset]; |
c61a4043 MN |
70 | int optlen; |
71 | ||
72 | if (opttype == type) | |
73 | return offset; | |
74 | ||
75 | switch (opttype) { | |
76 | case IPV6_TLV_PAD0: | |
77 | optlen = 1; | |
78 | break; | |
79 | default: | |
d56f90a7 | 80 | optlen = nh[offset + 1] + 2; |
c61a4043 MN |
81 | if (optlen > len) |
82 | goto bad; | |
83 | break; | |
84 | } | |
85 | offset += optlen; | |
86 | len -= optlen; | |
87 | } | |
88 | /* not_found */ | |
c61a4043 MN |
89 | bad: |
90 | return -1; | |
91 | } | |
59fbb3a6 | 92 | EXPORT_SYMBOL_GPL(ipv6_find_tlv); |
c61a4043 | 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; | |
e5bbef20 | 104 | int (*func)(struct sk_buff *skb, int offset); |
1da177e4 LT |
105 | }; |
106 | ||
107 | /********************* | |
108 | Generic functions | |
109 | *********************/ | |
110 | ||
111 | /* An unknown option is detected, decide what to do */ | |
112 | ||
e5bbef20 | 113 | static int ip6_tlvopt_unknown(struct sk_buff *skb, int optoff) |
1da177e4 | 114 | { |
d56f90a7 | 115 | switch ((skb_network_header(skb)[optoff] & 0xC0) >> 6) { |
1da177e4 LT |
116 | case 0: /* ignore */ |
117 | return 1; | |
118 | ||
119 | case 1: /* drop packet */ | |
120 | break; | |
121 | ||
122 | case 3: /* Send ICMP if not a multicast address and drop packet */ | |
123 | /* Actually, it is redundant check. icmp_send | |
124 | will recheck in any case. | |
125 | */ | |
0660e03f | 126 | if (ipv6_addr_is_multicast(&ipv6_hdr(skb)->daddr)) |
1da177e4 LT |
127 | break; |
128 | case 2: /* send ICMP PARM PROB regardless and drop packet */ | |
129 | icmpv6_param_prob(skb, ICMPV6_UNK_OPTION, optoff); | |
130 | return 0; | |
3ff50b79 | 131 | } |
1da177e4 LT |
132 | |
133 | kfree_skb(skb); | |
134 | return 0; | |
135 | } | |
136 | ||
137 | /* Parse tlv encoded option header (hop-by-hop or destination) */ | |
138 | ||
e5bbef20 | 139 | static int ip6_parse_tlv(struct tlvtype_proc *procs, struct sk_buff *skb) |
1da177e4 LT |
140 | { |
141 | struct tlvtype_proc *curr; | |
d56f90a7 | 142 | const unsigned char *nh = skb_network_header(skb); |
cfe1fc77 | 143 | int off = skb_network_header_len(skb); |
9c70220b | 144 | int len = (skb_transport_header(skb)[1] + 1) << 3; |
1da177e4 | 145 | |
ea2ae17d | 146 | if (skb_transport_offset(skb) + len > skb_headlen(skb)) |
1da177e4 LT |
147 | goto bad; |
148 | ||
149 | off += 2; | |
150 | len -= 2; | |
151 | ||
152 | while (len > 0) { | |
d56f90a7 | 153 | int optlen = nh[off + 1] + 2; |
1da177e4 | 154 | |
d56f90a7 | 155 | switch (nh[off]) { |
1da177e4 LT |
156 | case IPV6_TLV_PAD0: |
157 | optlen = 1; | |
158 | break; | |
159 | ||
160 | case IPV6_TLV_PADN: | |
161 | break; | |
162 | ||
163 | default: /* Other TLV code so scan list */ | |
164 | if (optlen > len) | |
165 | goto bad; | |
166 | for (curr=procs; curr->type >= 0; curr++) { | |
d56f90a7 | 167 | if (curr->type == nh[off]) { |
1ab1457c YH |
168 | /* type specific length/alignment |
169 | checks will be performed in the | |
1da177e4 | 170 | func(). */ |
e5bbef20 | 171 | if (curr->func(skb, off) == 0) |
1da177e4 LT |
172 | return 0; |
173 | break; | |
174 | } | |
175 | } | |
176 | if (curr->type < 0) { | |
e5bbef20 | 177 | if (ip6_tlvopt_unknown(skb, off) == 0) |
1da177e4 LT |
178 | return 0; |
179 | } | |
180 | break; | |
181 | } | |
182 | off += optlen; | |
183 | len -= optlen; | |
184 | } | |
185 | if (len == 0) | |
186 | return 1; | |
187 | bad: | |
188 | kfree_skb(skb); | |
189 | return 0; | |
190 | } | |
191 | ||
192 | /***************************** | |
193 | Destination options header. | |
194 | *****************************/ | |
195 | ||
59fbb3a6 | 196 | #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE) |
e5bbef20 | 197 | static int ipv6_dest_hao(struct sk_buff *skb, int optoff) |
a831f5bb | 198 | { |
a831f5bb MN |
199 | struct ipv6_destopt_hao *hao; |
200 | struct inet6_skb_parm *opt = IP6CB(skb); | |
0660e03f | 201 | struct ipv6hdr *ipv6h = ipv6_hdr(skb); |
a831f5bb MN |
202 | struct in6_addr tmp_addr; |
203 | int ret; | |
204 | ||
205 | if (opt->dsthao) { | |
206 | LIMIT_NETDEBUG(KERN_DEBUG "hao duplicated\n"); | |
207 | goto discard; | |
208 | } | |
209 | opt->dsthao = opt->dst1; | |
210 | opt->dst1 = 0; | |
211 | ||
d56f90a7 | 212 | hao = (struct ipv6_destopt_hao *)(skb_network_header(skb) + optoff); |
a831f5bb MN |
213 | |
214 | if (hao->length != 16) { | |
215 | LIMIT_NETDEBUG( | |
216 | KERN_DEBUG "hao invalid option length = %d\n", hao->length); | |
217 | goto discard; | |
218 | } | |
219 | ||
220 | if (!(ipv6_addr_type(&hao->addr) & IPV6_ADDR_UNICAST)) { | |
221 | LIMIT_NETDEBUG( | |
5b095d98 | 222 | KERN_DEBUG "hao is not an unicast addr: %pI6\n", &hao->addr); |
a831f5bb MN |
223 | goto discard; |
224 | } | |
225 | ||
226 | ret = xfrm6_input_addr(skb, (xfrm_address_t *)&ipv6h->daddr, | |
227 | (xfrm_address_t *)&hao->addr, IPPROTO_DSTOPTS); | |
228 | if (unlikely(ret < 0)) | |
229 | goto discard; | |
230 | ||
231 | if (skb_cloned(skb)) { | |
65c88466 | 232 | if (pskb_expand_head(skb, 0, 0, GFP_ATOMIC)) |
a831f5bb MN |
233 | goto discard; |
234 | ||
a831f5bb | 235 | /* update all variable using below by copied skbuff */ |
65c88466 | 236 | hao = (struct ipv6_destopt_hao *)(skb_network_header(skb) + |
d56f90a7 | 237 | optoff); |
65c88466 | 238 | ipv6h = ipv6_hdr(skb); |
a831f5bb MN |
239 | } |
240 | ||
241 | if (skb->ip_summed == CHECKSUM_COMPLETE) | |
242 | skb->ip_summed = CHECKSUM_NONE; | |
243 | ||
244 | ipv6_addr_copy(&tmp_addr, &ipv6h->saddr); | |
245 | ipv6_addr_copy(&ipv6h->saddr, &hao->addr); | |
246 | ipv6_addr_copy(&hao->addr, &tmp_addr); | |
247 | ||
b7aa0bf7 | 248 | if (skb->tstamp.tv64 == 0) |
a831f5bb MN |
249 | __net_timestamp(skb); |
250 | ||
251 | return 1; | |
252 | ||
253 | discard: | |
254 | kfree_skb(skb); | |
255 | return 0; | |
256 | } | |
257 | #endif | |
258 | ||
1da177e4 | 259 | static struct tlvtype_proc tlvprocdestopt_lst[] = { |
59fbb3a6 | 260 | #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE) |
a831f5bb MN |
261 | { |
262 | .type = IPV6_TLV_HAO, | |
263 | .func = ipv6_dest_hao, | |
264 | }, | |
265 | #endif | |
1da177e4 LT |
266 | {-1, NULL} |
267 | }; | |
268 | ||
e5bbef20 | 269 | static int ipv6_destopt_rcv(struct sk_buff *skb) |
1da177e4 | 270 | { |
1da177e4 | 271 | struct inet6_skb_parm *opt = IP6CB(skb); |
59fbb3a6 | 272 | #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE) |
a831f5bb MN |
273 | __u16 dstbuf; |
274 | #endif | |
a11d206d | 275 | struct dst_entry *dst; |
1da177e4 | 276 | |
ea2ae17d ACM |
277 | if (!pskb_may_pull(skb, skb_transport_offset(skb) + 8) || |
278 | !pskb_may_pull(skb, (skb_transport_offset(skb) + | |
9c70220b | 279 | ((skb_transport_header(skb)[1] + 1) << 3)))) { |
adf30907 | 280 | IP6_INC_STATS_BH(dev_net(skb_dst(skb)->dev), ip6_dst_idev(skb_dst(skb)), |
a11d206d | 281 | IPSTATS_MIB_INHDRERRORS); |
1da177e4 LT |
282 | kfree_skb(skb); |
283 | return -1; | |
284 | } | |
285 | ||
cfe1fc77 | 286 | opt->lastopt = opt->dst1 = skb_network_header_len(skb); |
59fbb3a6 | 287 | #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE) |
a831f5bb MN |
288 | dstbuf = opt->dst1; |
289 | #endif | |
1da177e4 | 290 | |
adf30907 | 291 | dst = dst_clone(skb_dst(skb)); |
e5bbef20 | 292 | if (ip6_parse_tlv(tlvprocdestopt_lst, skb)) { |
a11d206d | 293 | dst_release(dst); |
b0e380b1 | 294 | skb->transport_header += (skb_transport_header(skb)[1] + 1) << 3; |
dc435e6d | 295 | opt = IP6CB(skb); |
59fbb3a6 | 296 | #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE) |
a831f5bb MN |
297 | opt->nhoff = dstbuf; |
298 | #else | |
951dbc8a | 299 | opt->nhoff = opt->dst1; |
a831f5bb | 300 | #endif |
1da177e4 LT |
301 | return 1; |
302 | } | |
303 | ||
483a47d2 DL |
304 | IP6_INC_STATS_BH(dev_net(dst->dev), |
305 | ip6_dst_idev(dst), IPSTATS_MIB_INHDRERRORS); | |
a11d206d | 306 | dst_release(dst); |
1da177e4 LT |
307 | return -1; |
308 | } | |
309 | ||
1da177e4 LT |
310 | /******************************** |
311 | Routing header. | |
312 | ********************************/ | |
313 | ||
e5bbef20 | 314 | static int ipv6_rthdr_rcv(struct sk_buff *skb) |
1da177e4 | 315 | { |
1da177e4 | 316 | struct inet6_skb_parm *opt = IP6CB(skb); |
65d4ed92 | 317 | struct in6_addr *addr = NULL; |
1da177e4 | 318 | struct in6_addr daddr; |
0bcbc926 | 319 | struct inet6_dev *idev; |
1da177e4 | 320 | int n, i; |
1da177e4 LT |
321 | struct ipv6_rt_hdr *hdr; |
322 | struct rt0_hdr *rthdr; | |
483a47d2 DL |
323 | struct net *net = dev_net(skb->dev); |
324 | int accept_source_route = net->ipv6.devconf_all->accept_source_route; | |
0bcbc926 | 325 | |
c382bb9d YH |
326 | idev = in6_dev_get(skb->dev); |
327 | if (idev) { | |
328 | if (accept_source_route > idev->cnf.accept_source_route) | |
329 | accept_source_route = idev->cnf.accept_source_route; | |
0bcbc926 | 330 | in6_dev_put(idev); |
0bcbc926 YH |
331 | } |
332 | ||
ea2ae17d ACM |
333 | if (!pskb_may_pull(skb, skb_transport_offset(skb) + 8) || |
334 | !pskb_may_pull(skb, (skb_transport_offset(skb) + | |
9c70220b | 335 | ((skb_transport_header(skb)[1] + 1) << 3)))) { |
adf30907 | 336 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), |
a11d206d | 337 | IPSTATS_MIB_INHDRERRORS); |
1da177e4 LT |
338 | kfree_skb(skb); |
339 | return -1; | |
340 | } | |
341 | ||
9c70220b | 342 | hdr = (struct ipv6_rt_hdr *)skb_transport_header(skb); |
1da177e4 | 343 | |
0660e03f | 344 | if (ipv6_addr_is_multicast(&ipv6_hdr(skb)->daddr) || |
1da177e4 | 345 | skb->pkt_type != PACKET_HOST) { |
adf30907 | 346 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), |
a11d206d | 347 | IPSTATS_MIB_INADDRERRORS); |
1da177e4 LT |
348 | kfree_skb(skb); |
349 | return -1; | |
350 | } | |
351 | ||
352 | looped_back: | |
353 | if (hdr->segments_left == 0) { | |
65d4ed92 | 354 | switch (hdr->type) { |
59fbb3a6 | 355 | #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE) |
65d4ed92 MN |
356 | case IPV6_SRCRT_TYPE_2: |
357 | /* Silently discard type 2 header unless it was | |
358 | * processed by own | |
359 | */ | |
360 | if (!addr) { | |
adf30907 | 361 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), |
a11d206d | 362 | IPSTATS_MIB_INADDRERRORS); |
65d4ed92 MN |
363 | kfree_skb(skb); |
364 | return -1; | |
365 | } | |
366 | break; | |
367 | #endif | |
368 | default: | |
369 | break; | |
370 | } | |
371 | ||
cfe1fc77 | 372 | opt->lastopt = opt->srcrt = skb_network_header_len(skb); |
b0e380b1 | 373 | skb->transport_header += (hdr->hdrlen + 1) << 3; |
1da177e4 LT |
374 | opt->dst0 = opt->dst1; |
375 | opt->dst1 = 0; | |
d56f90a7 | 376 | opt->nhoff = (&hdr->nexthdr) - skb_network_header(skb); |
1da177e4 LT |
377 | return 1; |
378 | } | |
379 | ||
65d4ed92 | 380 | switch (hdr->type) { |
59fbb3a6 | 381 | #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE) |
65d4ed92 | 382 | case IPV6_SRCRT_TYPE_2: |
c382bb9d YH |
383 | if (accept_source_route < 0) |
384 | goto unknown_rh; | |
65d4ed92 MN |
385 | /* Silently discard invalid RTH type 2 */ |
386 | if (hdr->hdrlen != 2 || hdr->segments_left != 1) { | |
adf30907 | 387 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), |
a11d206d | 388 | IPSTATS_MIB_INHDRERRORS); |
65d4ed92 MN |
389 | kfree_skb(skb); |
390 | return -1; | |
391 | } | |
392 | break; | |
393 | #endif | |
c382bb9d YH |
394 | default: |
395 | goto unknown_rh; | |
1da177e4 | 396 | } |
1da177e4 LT |
397 | |
398 | /* | |
399 | * This is the routing header forwarding algorithm from | |
400 | * RFC 2460, page 16. | |
401 | */ | |
402 | ||
403 | n = hdr->hdrlen >> 1; | |
404 | ||
405 | if (hdr->segments_left > n) { | |
adf30907 | 406 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), |
a11d206d | 407 | IPSTATS_MIB_INHDRERRORS); |
d56f90a7 ACM |
408 | icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, |
409 | ((&hdr->segments_left) - | |
410 | skb_network_header(skb))); | |
1da177e4 LT |
411 | return -1; |
412 | } | |
413 | ||
414 | /* We are about to mangle packet header. Be careful! | |
415 | Do not damage packets queued somewhere. | |
416 | */ | |
417 | if (skb_cloned(skb)) { | |
1da177e4 | 418 | /* the copy is a forwarded packet */ |
65c88466 | 419 | if (pskb_expand_head(skb, 0, 0, GFP_ATOMIC)) { |
adf30907 | 420 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), |
a11d206d YH |
421 | IPSTATS_MIB_OUTDISCARDS); |
422 | kfree_skb(skb); | |
1da177e4 LT |
423 | return -1; |
424 | } | |
65c88466 | 425 | hdr = (struct ipv6_rt_hdr *)skb_transport_header(skb); |
1da177e4 LT |
426 | } |
427 | ||
84fa7933 | 428 | if (skb->ip_summed == CHECKSUM_COMPLETE) |
1da177e4 LT |
429 | skb->ip_summed = CHECKSUM_NONE; |
430 | ||
431 | i = n - --hdr->segments_left; | |
432 | ||
433 | rthdr = (struct rt0_hdr *) hdr; | |
434 | addr = rthdr->addr; | |
435 | addr += i - 1; | |
436 | ||
65d4ed92 | 437 | switch (hdr->type) { |
59fbb3a6 | 438 | #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE) |
65d4ed92 MN |
439 | case IPV6_SRCRT_TYPE_2: |
440 | if (xfrm6_input_addr(skb, (xfrm_address_t *)addr, | |
0660e03f | 441 | (xfrm_address_t *)&ipv6_hdr(skb)->saddr, |
65d4ed92 | 442 | IPPROTO_ROUTING) < 0) { |
adf30907 | 443 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), |
a11d206d | 444 | IPSTATS_MIB_INADDRERRORS); |
65d4ed92 MN |
445 | kfree_skb(skb); |
446 | return -1; | |
447 | } | |
adf30907 ED |
448 | if (!ipv6_chk_home_addr(dev_net(skb_dst(skb)->dev), addr)) { |
449 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), | |
a11d206d | 450 | IPSTATS_MIB_INADDRERRORS); |
65d4ed92 MN |
451 | kfree_skb(skb); |
452 | return -1; | |
453 | } | |
454 | break; | |
455 | #endif | |
456 | default: | |
457 | break; | |
458 | } | |
459 | ||
1da177e4 | 460 | if (ipv6_addr_is_multicast(addr)) { |
adf30907 | 461 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), |
a11d206d | 462 | IPSTATS_MIB_INADDRERRORS); |
1da177e4 LT |
463 | kfree_skb(skb); |
464 | return -1; | |
465 | } | |
466 | ||
467 | ipv6_addr_copy(&daddr, addr); | |
0660e03f ACM |
468 | ipv6_addr_copy(addr, &ipv6_hdr(skb)->daddr); |
469 | ipv6_addr_copy(&ipv6_hdr(skb)->daddr, &daddr); | |
1da177e4 | 470 | |
adf30907 | 471 | skb_dst_drop(skb); |
1da177e4 | 472 | ip6_route_input(skb); |
adf30907 | 473 | if (skb_dst(skb)->error) { |
d56f90a7 | 474 | skb_push(skb, skb->data - skb_network_header(skb)); |
1da177e4 LT |
475 | dst_input(skb); |
476 | return -1; | |
477 | } | |
478 | ||
adf30907 | 479 | if (skb_dst(skb)->dev->flags&IFF_LOOPBACK) { |
0660e03f | 480 | if (ipv6_hdr(skb)->hop_limit <= 1) { |
adf30907 | 481 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), |
a11d206d | 482 | IPSTATS_MIB_INHDRERRORS); |
1da177e4 LT |
483 | icmpv6_send(skb, ICMPV6_TIME_EXCEED, ICMPV6_EXC_HOPLIMIT, |
484 | 0, skb->dev); | |
485 | kfree_skb(skb); | |
486 | return -1; | |
487 | } | |
0660e03f | 488 | ipv6_hdr(skb)->hop_limit--; |
1da177e4 LT |
489 | goto looped_back; |
490 | } | |
491 | ||
d56f90a7 | 492 | skb_push(skb, skb->data - skb_network_header(skb)); |
1da177e4 LT |
493 | dst_input(skb); |
494 | return -1; | |
c382bb9d YH |
495 | |
496 | unknown_rh: | |
adf30907 | 497 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), IPSTATS_MIB_INHDRERRORS); |
c382bb9d YH |
498 | icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, |
499 | (&hdr->type) - skb_network_header(skb)); | |
500 | return -1; | |
1da177e4 LT |
501 | } |
502 | ||
41135cc8 | 503 | static const struct inet6_protocol rthdr_protocol = { |
1da177e4 | 504 | .handler = ipv6_rthdr_rcv, |
adcfc7d0 | 505 | .flags = INET6_PROTO_NOPOLICY | INET6_PROTO_GSO_EXTHDR, |
1da177e4 LT |
506 | }; |
507 | ||
41135cc8 | 508 | static const struct inet6_protocol destopt_protocol = { |
248b238d DL |
509 | .handler = ipv6_destopt_rcv, |
510 | .flags = INET6_PROTO_NOPOLICY | INET6_PROTO_GSO_EXTHDR, | |
511 | }; | |
512 | ||
41135cc8 | 513 | static const struct inet6_protocol nodata_protocol = { |
248b238d DL |
514 | .handler = dst_discard, |
515 | .flags = INET6_PROTO_NOPOLICY, | |
516 | }; | |
517 | ||
518 | int __init ipv6_exthdrs_init(void) | |
1da177e4 | 519 | { |
248b238d DL |
520 | int ret; |
521 | ||
522 | ret = inet6_add_protocol(&rthdr_protocol, IPPROTO_ROUTING); | |
523 | if (ret) | |
524 | goto out; | |
525 | ||
526 | ret = inet6_add_protocol(&destopt_protocol, IPPROTO_DSTOPTS); | |
527 | if (ret) | |
528 | goto out_rthdr; | |
529 | ||
530 | ret = inet6_add_protocol(&nodata_protocol, IPPROTO_NONE); | |
531 | if (ret) | |
532 | goto out_destopt; | |
533 | ||
534 | out: | |
535 | return ret; | |
536 | out_rthdr: | |
537 | inet6_del_protocol(&rthdr_protocol, IPPROTO_ROUTING); | |
538 | out_destopt: | |
539 | inet6_del_protocol(&destopt_protocol, IPPROTO_DSTOPTS); | |
540 | goto out; | |
1da177e4 LT |
541 | }; |
542 | ||
248b238d DL |
543 | void ipv6_exthdrs_exit(void) |
544 | { | |
545 | inet6_del_protocol(&nodata_protocol, IPPROTO_NONE); | |
546 | inet6_del_protocol(&destopt_protocol, IPPROTO_DSTOPTS); | |
547 | inet6_del_protocol(&rthdr_protocol, IPPROTO_ROUTING); | |
548 | } | |
549 | ||
1da177e4 LT |
550 | /********************************** |
551 | Hop-by-hop options. | |
552 | **********************************/ | |
553 | ||
e76b2b25 | 554 | /* |
adf30907 | 555 | * Note: we cannot rely on skb_dst(skb) before we assign it in ip6_route_input(). |
e76b2b25 YH |
556 | */ |
557 | static inline struct inet6_dev *ipv6_skb_idev(struct sk_buff *skb) | |
558 | { | |
adf30907 | 559 | return skb_dst(skb) ? ip6_dst_idev(skb_dst(skb)) : __in6_dev_get(skb->dev); |
e76b2b25 YH |
560 | } |
561 | ||
1da177e4 LT |
562 | /* Router Alert as of RFC 2711 */ |
563 | ||
e5bbef20 | 564 | static int ipv6_hop_ra(struct sk_buff *skb, int optoff) |
1da177e4 | 565 | { |
d56f90a7 | 566 | const unsigned char *nh = skb_network_header(skb); |
a80ff03e | 567 | |
d56f90a7 | 568 | if (nh[optoff + 1] == 2) { |
1da177e4 LT |
569 | IP6CB(skb)->ra = optoff; |
570 | return 1; | |
571 | } | |
64ce2073 | 572 | LIMIT_NETDEBUG(KERN_DEBUG "ipv6_hop_ra: wrong RA length %d\n", |
d56f90a7 | 573 | nh[optoff + 1]); |
1da177e4 LT |
574 | kfree_skb(skb); |
575 | return 0; | |
576 | } | |
577 | ||
578 | /* Jumbo payload */ | |
579 | ||
e5bbef20 | 580 | static int ipv6_hop_jumbo(struct sk_buff *skb, int optoff) |
1da177e4 | 581 | { |
d56f90a7 | 582 | const unsigned char *nh = skb_network_header(skb); |
1da177e4 | 583 | u32 pkt_len; |
adf30907 | 584 | struct net *net = dev_net(skb_dst(skb)->dev); |
1da177e4 | 585 | |
d56f90a7 | 586 | if (nh[optoff + 1] != 4 || (optoff & 3) != 2) { |
64ce2073 | 587 | LIMIT_NETDEBUG(KERN_DEBUG "ipv6_hop_jumbo: wrong jumbo opt length/alignment %d\n", |
d56f90a7 | 588 | nh[optoff+1]); |
483a47d2 | 589 | IP6_INC_STATS_BH(net, ipv6_skb_idev(skb), |
a11d206d | 590 | IPSTATS_MIB_INHDRERRORS); |
1da177e4 LT |
591 | goto drop; |
592 | } | |
593 | ||
d56f90a7 | 594 | pkt_len = ntohl(*(__be32 *)(nh + optoff + 2)); |
1da177e4 | 595 | if (pkt_len <= IPV6_MAXPLEN) { |
483a47d2 DL |
596 | IP6_INC_STATS_BH(net, ipv6_skb_idev(skb), |
597 | IPSTATS_MIB_INHDRERRORS); | |
1da177e4 LT |
598 | icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, optoff+2); |
599 | return 0; | |
600 | } | |
0660e03f | 601 | if (ipv6_hdr(skb)->payload_len) { |
483a47d2 DL |
602 | IP6_INC_STATS_BH(net, ipv6_skb_idev(skb), |
603 | IPSTATS_MIB_INHDRERRORS); | |
1da177e4 LT |
604 | icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, optoff); |
605 | return 0; | |
606 | } | |
607 | ||
608 | if (pkt_len > skb->len - sizeof(struct ipv6hdr)) { | |
483a47d2 DL |
609 | IP6_INC_STATS_BH(net, ipv6_skb_idev(skb), |
610 | IPSTATS_MIB_INTRUNCATEDPKTS); | |
1da177e4 LT |
611 | goto drop; |
612 | } | |
42ca89c1 SH |
613 | |
614 | if (pskb_trim_rcsum(skb, pkt_len + sizeof(struct ipv6hdr))) | |
615 | goto drop; | |
616 | ||
1da177e4 LT |
617 | return 1; |
618 | ||
619 | drop: | |
620 | kfree_skb(skb); | |
621 | return 0; | |
622 | } | |
623 | ||
624 | static struct tlvtype_proc tlvprochopopt_lst[] = { | |
625 | { | |
626 | .type = IPV6_TLV_ROUTERALERT, | |
627 | .func = ipv6_hop_ra, | |
628 | }, | |
629 | { | |
630 | .type = IPV6_TLV_JUMBO, | |
631 | .func = ipv6_hop_jumbo, | |
632 | }, | |
633 | { -1, } | |
634 | }; | |
635 | ||
e5bbef20 | 636 | int ipv6_parse_hopopts(struct sk_buff *skb) |
1da177e4 | 637 | { |
951dbc8a PM |
638 | struct inet6_skb_parm *opt = IP6CB(skb); |
639 | ||
ec670095 | 640 | /* |
d56f90a7 | 641 | * skb_network_header(skb) is equal to skb->data, and |
cfe1fc77 | 642 | * skb_network_header_len(skb) is always equal to |
ec670095 YH |
643 | * sizeof(struct ipv6hdr) by definition of |
644 | * hop-by-hop options. | |
645 | */ | |
646 | if (!pskb_may_pull(skb, sizeof(struct ipv6hdr) + 8) || | |
9c70220b ACM |
647 | !pskb_may_pull(skb, (sizeof(struct ipv6hdr) + |
648 | ((skb_transport_header(skb)[1] + 1) << 3)))) { | |
ec670095 YH |
649 | kfree_skb(skb); |
650 | return -1; | |
651 | } | |
652 | ||
951dbc8a | 653 | opt->hop = sizeof(struct ipv6hdr); |
e5bbef20 | 654 | if (ip6_parse_tlv(tlvprochopopt_lst, skb)) { |
b0e380b1 | 655 | skb->transport_header += (skb_transport_header(skb)[1] + 1) << 3; |
dc435e6d | 656 | opt = IP6CB(skb); |
951dbc8a | 657 | opt->nhoff = sizeof(struct ipv6hdr); |
b809739a | 658 | return 1; |
951dbc8a | 659 | } |
1da177e4 LT |
660 | return -1; |
661 | } | |
662 | ||
663 | /* | |
664 | * Creating outbound headers. | |
665 | * | |
666 | * "build" functions work when skb is filled from head to tail (datagram) | |
667 | * "push" functions work when headers are added from tail to head (tcp) | |
668 | * | |
669 | * In both cases we assume, that caller reserved enough room | |
670 | * for headers. | |
671 | */ | |
672 | ||
673 | static void ipv6_push_rthdr(struct sk_buff *skb, u8 *proto, | |
674 | struct ipv6_rt_hdr *opt, | |
675 | struct in6_addr **addr_p) | |
676 | { | |
677 | struct rt0_hdr *phdr, *ihdr; | |
678 | int hops; | |
679 | ||
680 | ihdr = (struct rt0_hdr *) opt; | |
1ab1457c | 681 | |
1da177e4 LT |
682 | phdr = (struct rt0_hdr *) skb_push(skb, (ihdr->rt_hdr.hdrlen + 1) << 3); |
683 | memcpy(phdr, ihdr, sizeof(struct rt0_hdr)); | |
684 | ||
685 | hops = ihdr->rt_hdr.hdrlen >> 1; | |
686 | ||
687 | if (hops > 1) | |
688 | memcpy(phdr->addr, ihdr->addr + 1, | |
689 | (hops - 1) * sizeof(struct in6_addr)); | |
690 | ||
691 | ipv6_addr_copy(phdr->addr + (hops - 1), *addr_p); | |
692 | *addr_p = ihdr->addr; | |
693 | ||
694 | phdr->rt_hdr.nexthdr = *proto; | |
695 | *proto = NEXTHDR_ROUTING; | |
696 | } | |
697 | ||
698 | static void ipv6_push_exthdr(struct sk_buff *skb, u8 *proto, u8 type, struct ipv6_opt_hdr *opt) | |
699 | { | |
700 | struct ipv6_opt_hdr *h = (struct ipv6_opt_hdr *)skb_push(skb, ipv6_optlen(opt)); | |
701 | ||
702 | memcpy(h, opt, ipv6_optlen(opt)); | |
703 | h->nexthdr = *proto; | |
704 | *proto = type; | |
705 | } | |
706 | ||
707 | void ipv6_push_nfrag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt, | |
708 | u8 *proto, | |
709 | struct in6_addr **daddr) | |
710 | { | |
333fad53 | 711 | if (opt->srcrt) { |
1da177e4 | 712 | ipv6_push_rthdr(skb, proto, opt->srcrt, daddr); |
333fad53 YH |
713 | /* |
714 | * IPV6_RTHDRDSTOPTS is ignored | |
715 | * unless IPV6_RTHDR is set (RFC3542). | |
716 | */ | |
717 | if (opt->dst0opt) | |
718 | ipv6_push_exthdr(skb, proto, NEXTHDR_DEST, opt->dst0opt); | |
719 | } | |
1da177e4 LT |
720 | if (opt->hopopt) |
721 | ipv6_push_exthdr(skb, proto, NEXTHDR_HOP, opt->hopopt); | |
722 | } | |
723 | ||
7159039a YH |
724 | EXPORT_SYMBOL(ipv6_push_nfrag_opts); |
725 | ||
1da177e4 LT |
726 | void ipv6_push_frag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt, u8 *proto) |
727 | { | |
728 | if (opt->dst1opt) | |
729 | ipv6_push_exthdr(skb, proto, NEXTHDR_DEST, opt->dst1opt); | |
730 | } | |
731 | ||
732 | struct ipv6_txoptions * | |
733 | ipv6_dup_options(struct sock *sk, struct ipv6_txoptions *opt) | |
734 | { | |
735 | struct ipv6_txoptions *opt2; | |
736 | ||
737 | opt2 = sock_kmalloc(sk, opt->tot_len, GFP_ATOMIC); | |
738 | if (opt2) { | |
739 | long dif = (char*)opt2 - (char*)opt; | |
740 | memcpy(opt2, opt, opt->tot_len); | |
741 | if (opt2->hopopt) | |
742 | *((char**)&opt2->hopopt) += dif; | |
743 | if (opt2->dst0opt) | |
744 | *((char**)&opt2->dst0opt) += dif; | |
745 | if (opt2->dst1opt) | |
746 | *((char**)&opt2->dst1opt) += dif; | |
747 | if (opt2->srcrt) | |
748 | *((char**)&opt2->srcrt) += dif; | |
749 | } | |
750 | return opt2; | |
751 | } | |
333fad53 | 752 | |
3cf3dc6c ACM |
753 | EXPORT_SYMBOL_GPL(ipv6_dup_options); |
754 | ||
333fad53 YH |
755 | static int ipv6_renew_option(void *ohdr, |
756 | struct ipv6_opt_hdr __user *newopt, int newoptlen, | |
757 | int inherit, | |
758 | struct ipv6_opt_hdr **hdr, | |
759 | char **p) | |
760 | { | |
761 | if (inherit) { | |
762 | if (ohdr) { | |
763 | memcpy(*p, ohdr, ipv6_optlen((struct ipv6_opt_hdr *)ohdr)); | |
764 | *hdr = (struct ipv6_opt_hdr *)*p; | |
765 | *p += CMSG_ALIGN(ipv6_optlen(*(struct ipv6_opt_hdr **)hdr)); | |
766 | } | |
767 | } else { | |
768 | if (newopt) { | |
769 | if (copy_from_user(*p, newopt, newoptlen)) | |
770 | return -EFAULT; | |
771 | *hdr = (struct ipv6_opt_hdr *)*p; | |
772 | if (ipv6_optlen(*(struct ipv6_opt_hdr **)hdr) > newoptlen) | |
773 | return -EINVAL; | |
774 | *p += CMSG_ALIGN(newoptlen); | |
775 | } | |
776 | } | |
777 | return 0; | |
778 | } | |
779 | ||
780 | struct ipv6_txoptions * | |
781 | ipv6_renew_options(struct sock *sk, struct ipv6_txoptions *opt, | |
782 | int newtype, | |
783 | struct ipv6_opt_hdr __user *newopt, int newoptlen) | |
784 | { | |
785 | int tot_len = 0; | |
786 | char *p; | |
787 | struct ipv6_txoptions *opt2; | |
788 | int err; | |
789 | ||
99c7bc01 YH |
790 | if (opt) { |
791 | if (newtype != IPV6_HOPOPTS && opt->hopopt) | |
792 | tot_len += CMSG_ALIGN(ipv6_optlen(opt->hopopt)); | |
793 | if (newtype != IPV6_RTHDRDSTOPTS && opt->dst0opt) | |
794 | tot_len += CMSG_ALIGN(ipv6_optlen(opt->dst0opt)); | |
795 | if (newtype != IPV6_RTHDR && opt->srcrt) | |
796 | tot_len += CMSG_ALIGN(ipv6_optlen(opt->srcrt)); | |
797 | if (newtype != IPV6_DSTOPTS && opt->dst1opt) | |
798 | tot_len += CMSG_ALIGN(ipv6_optlen(opt->dst1opt)); | |
799 | } | |
800 | ||
333fad53 YH |
801 | if (newopt && newoptlen) |
802 | tot_len += CMSG_ALIGN(newoptlen); | |
803 | ||
804 | if (!tot_len) | |
805 | return NULL; | |
806 | ||
8b8aa4b5 | 807 | tot_len += sizeof(*opt2); |
333fad53 YH |
808 | opt2 = sock_kmalloc(sk, tot_len, GFP_ATOMIC); |
809 | if (!opt2) | |
810 | return ERR_PTR(-ENOBUFS); | |
811 | ||
812 | memset(opt2, 0, tot_len); | |
813 | ||
814 | opt2->tot_len = tot_len; | |
815 | p = (char *)(opt2 + 1); | |
816 | ||
99c7bc01 | 817 | err = ipv6_renew_option(opt ? opt->hopopt : NULL, newopt, newoptlen, |
333fad53 YH |
818 | newtype != IPV6_HOPOPTS, |
819 | &opt2->hopopt, &p); | |
820 | if (err) | |
821 | goto out; | |
822 | ||
99c7bc01 | 823 | err = ipv6_renew_option(opt ? opt->dst0opt : NULL, newopt, newoptlen, |
333fad53 YH |
824 | newtype != IPV6_RTHDRDSTOPTS, |
825 | &opt2->dst0opt, &p); | |
826 | if (err) | |
827 | goto out; | |
828 | ||
99c7bc01 | 829 | err = ipv6_renew_option(opt ? opt->srcrt : NULL, newopt, newoptlen, |
333fad53 | 830 | newtype != IPV6_RTHDR, |
99c7bc01 | 831 | (struct ipv6_opt_hdr **)&opt2->srcrt, &p); |
333fad53 YH |
832 | if (err) |
833 | goto out; | |
834 | ||
99c7bc01 | 835 | err = ipv6_renew_option(opt ? opt->dst1opt : NULL, newopt, newoptlen, |
333fad53 YH |
836 | newtype != IPV6_DSTOPTS, |
837 | &opt2->dst1opt, &p); | |
838 | if (err) | |
839 | goto out; | |
840 | ||
841 | opt2->opt_nflen = (opt2->hopopt ? ipv6_optlen(opt2->hopopt) : 0) + | |
842 | (opt2->dst0opt ? ipv6_optlen(opt2->dst0opt) : 0) + | |
843 | (opt2->srcrt ? ipv6_optlen(opt2->srcrt) : 0); | |
844 | opt2->opt_flen = (opt2->dst1opt ? ipv6_optlen(opt2->dst1opt) : 0); | |
845 | ||
846 | return opt2; | |
847 | out: | |
8b8aa4b5 | 848 | sock_kfree_s(sk, opt2, opt2->tot_len); |
333fad53 YH |
849 | return ERR_PTR(err); |
850 | } | |
851 | ||
df9890c3 YH |
852 | struct ipv6_txoptions *ipv6_fixup_options(struct ipv6_txoptions *opt_space, |
853 | struct ipv6_txoptions *opt) | |
854 | { | |
855 | /* | |
856 | * ignore the dest before srcrt unless srcrt is being included. | |
857 | * --yoshfuji | |
858 | */ | |
859 | if (opt && opt->dst0opt && !opt->srcrt) { | |
860 | if (opt_space != opt) { | |
861 | memcpy(opt_space, opt, sizeof(*opt_space)); | |
862 | opt = opt_space; | |
863 | } | |
864 | opt->opt_nflen -= ipv6_optlen(opt->dst0opt); | |
865 | opt->dst0opt = NULL; | |
866 | } | |
867 | ||
868 | return opt; | |
869 | } | |
870 |