]>
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 | * | |
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> | |
5a0e3ad6 | 32 | #include <linux/slab.h> |
bc3b2d7f | 33 | #include <linux/export.h> |
1da177e4 | 34 | |
352e512c | 35 | #include <net/dst.h> |
1da177e4 LT |
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> | |
59fbb3a6 | 46 | #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE) |
65d4ed92 MN |
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 | { | |
d56f90a7 | 54 | const unsigned char *nh = skb_network_header(skb); |
27a884dc | 55 | int packet_len = skb->tail - skb->network_header; |
c61a4043 MN |
56 | struct ipv6_opt_hdr *hdr; |
57 | int len; | |
58 | ||
59 | if (offset + 2 > packet_len) | |
60 | goto bad; | |
d56f90a7 | 61 | hdr = (struct ipv6_opt_hdr *)(nh + offset); |
c61a4043 MN |
62 | len = ((hdr->hdrlen + 1) << 3); |
63 | ||
64 | if (offset + len > packet_len) | |
65 | goto bad; | |
66 | ||
67 | offset += 2; | |
68 | len -= 2; | |
69 | ||
70 | while (len > 0) { | |
d56f90a7 | 71 | int opttype = nh[offset]; |
c61a4043 MN |
72 | int optlen; |
73 | ||
74 | if (opttype == type) | |
75 | return offset; | |
76 | ||
77 | switch (opttype) { | |
1de5a71c | 78 | case IPV6_TLV_PAD1: |
c61a4043 MN |
79 | optlen = 1; |
80 | break; | |
81 | default: | |
d56f90a7 | 82 | optlen = nh[offset + 1] + 2; |
c61a4043 MN |
83 | if (optlen > len) |
84 | goto bad; | |
85 | break; | |
86 | } | |
87 | offset += optlen; | |
88 | len -= optlen; | |
89 | } | |
90 | /* not_found */ | |
c61a4043 MN |
91 | bad: |
92 | return -1; | |
93 | } | |
59fbb3a6 | 94 | EXPORT_SYMBOL_GPL(ipv6_find_tlv); |
c61a4043 | 95 | |
1da177e4 LT |
96 | /* |
97 | * Parsing tlv encoded headers. | |
98 | * | |
99 | * Parsing function "func" returns 1, if parsing succeed | |
100 | * and 0, if it failed. | |
101 | * It MUST NOT touch skb->h. | |
102 | */ | |
103 | ||
104 | struct tlvtype_proc { | |
105 | int type; | |
e5bbef20 | 106 | int (*func)(struct sk_buff *skb, int offset); |
1da177e4 LT |
107 | }; |
108 | ||
109 | /********************* | |
110 | Generic functions | |
111 | *********************/ | |
112 | ||
113 | /* An unknown option is detected, decide what to do */ | |
114 | ||
e5bbef20 | 115 | static int ip6_tlvopt_unknown(struct sk_buff *skb, int optoff) |
1da177e4 | 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 | ||
e5bbef20 | 141 | static int ip6_parse_tlv(struct tlvtype_proc *procs, struct sk_buff *skb) |
1da177e4 LT |
142 | { |
143 | struct tlvtype_proc *curr; | |
d56f90a7 | 144 | const unsigned char *nh = skb_network_header(skb); |
cfe1fc77 | 145 | int off = skb_network_header_len(skb); |
9c70220b | 146 | int len = (skb_transport_header(skb)[1] + 1) << 3; |
1da177e4 | 147 | |
ea2ae17d | 148 | if (skb_transport_offset(skb) + len > skb_headlen(skb)) |
1da177e4 LT |
149 | goto bad; |
150 | ||
151 | off += 2; | |
152 | len -= 2; | |
153 | ||
154 | while (len > 0) { | |
d56f90a7 | 155 | int optlen = nh[off + 1] + 2; |
c1412fce | 156 | int i; |
1da177e4 | 157 | |
d56f90a7 | 158 | switch (nh[off]) { |
1de5a71c | 159 | case IPV6_TLV_PAD1: |
1da177e4 LT |
160 | optlen = 1; |
161 | break; | |
162 | ||
163 | case IPV6_TLV_PADN: | |
c1412fce EZ |
164 | /* RFC 2460 states that the purpose of PadN is |
165 | * to align the containing header to multiples | |
166 | * of 8. 7 is therefore the highest valid value. | |
167 | * See also RFC 4942, Section 2.1.9.5. | |
168 | */ | |
169 | if (optlen > 7) | |
170 | goto bad; | |
171 | /* RFC 4942 recommends receiving hosts to | |
172 | * actively check PadN payload to contain | |
173 | * only zeroes. | |
174 | */ | |
175 | for (i = 2; i < optlen; i++) { | |
176 | if (nh[off + i] != 0) | |
177 | goto bad; | |
178 | } | |
1da177e4 LT |
179 | break; |
180 | ||
181 | default: /* Other TLV code so scan list */ | |
182 | if (optlen > len) | |
183 | goto bad; | |
184 | for (curr=procs; curr->type >= 0; curr++) { | |
d56f90a7 | 185 | if (curr->type == nh[off]) { |
1ab1457c YH |
186 | /* type specific length/alignment |
187 | checks will be performed in the | |
1da177e4 | 188 | func(). */ |
e5bbef20 | 189 | if (curr->func(skb, off) == 0) |
1da177e4 LT |
190 | return 0; |
191 | break; | |
192 | } | |
193 | } | |
194 | if (curr->type < 0) { | |
e5bbef20 | 195 | if (ip6_tlvopt_unknown(skb, off) == 0) |
1da177e4 LT |
196 | return 0; |
197 | } | |
198 | break; | |
199 | } | |
200 | off += optlen; | |
201 | len -= optlen; | |
202 | } | |
203 | if (len == 0) | |
204 | return 1; | |
205 | bad: | |
206 | kfree_skb(skb); | |
207 | return 0; | |
208 | } | |
209 | ||
210 | /***************************** | |
211 | Destination options header. | |
212 | *****************************/ | |
213 | ||
59fbb3a6 | 214 | #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE) |
e5bbef20 | 215 | static int ipv6_dest_hao(struct sk_buff *skb, int optoff) |
a831f5bb | 216 | { |
a831f5bb MN |
217 | struct ipv6_destopt_hao *hao; |
218 | struct inet6_skb_parm *opt = IP6CB(skb); | |
0660e03f | 219 | struct ipv6hdr *ipv6h = ipv6_hdr(skb); |
a831f5bb MN |
220 | struct in6_addr tmp_addr; |
221 | int ret; | |
222 | ||
223 | if (opt->dsthao) { | |
224 | LIMIT_NETDEBUG(KERN_DEBUG "hao duplicated\n"); | |
225 | goto discard; | |
226 | } | |
227 | opt->dsthao = opt->dst1; | |
228 | opt->dst1 = 0; | |
229 | ||
d56f90a7 | 230 | hao = (struct ipv6_destopt_hao *)(skb_network_header(skb) + optoff); |
a831f5bb MN |
231 | |
232 | if (hao->length != 16) { | |
233 | LIMIT_NETDEBUG( | |
234 | KERN_DEBUG "hao invalid option length = %d\n", hao->length); | |
235 | goto discard; | |
236 | } | |
237 | ||
238 | if (!(ipv6_addr_type(&hao->addr) & IPV6_ADDR_UNICAST)) { | |
239 | LIMIT_NETDEBUG( | |
5b095d98 | 240 | KERN_DEBUG "hao is not an unicast addr: %pI6\n", &hao->addr); |
a831f5bb MN |
241 | goto discard; |
242 | } | |
243 | ||
244 | ret = xfrm6_input_addr(skb, (xfrm_address_t *)&ipv6h->daddr, | |
245 | (xfrm_address_t *)&hao->addr, IPPROTO_DSTOPTS); | |
246 | if (unlikely(ret < 0)) | |
247 | goto discard; | |
248 | ||
249 | if (skb_cloned(skb)) { | |
65c88466 | 250 | if (pskb_expand_head(skb, 0, 0, GFP_ATOMIC)) |
a831f5bb MN |
251 | goto discard; |
252 | ||
a831f5bb | 253 | /* update all variable using below by copied skbuff */ |
65c88466 | 254 | hao = (struct ipv6_destopt_hao *)(skb_network_header(skb) + |
d56f90a7 | 255 | optoff); |
65c88466 | 256 | ipv6h = ipv6_hdr(skb); |
a831f5bb MN |
257 | } |
258 | ||
259 | if (skb->ip_summed == CHECKSUM_COMPLETE) | |
260 | skb->ip_summed = CHECKSUM_NONE; | |
261 | ||
4e3fd7a0 AD |
262 | tmp_addr = ipv6h->saddr; |
263 | ipv6h->saddr = hao->addr; | |
264 | hao->addr = tmp_addr; | |
a831f5bb | 265 | |
b7aa0bf7 | 266 | if (skb->tstamp.tv64 == 0) |
a831f5bb MN |
267 | __net_timestamp(skb); |
268 | ||
269 | return 1; | |
270 | ||
271 | discard: | |
272 | kfree_skb(skb); | |
273 | return 0; | |
274 | } | |
275 | #endif | |
276 | ||
1da177e4 | 277 | static struct tlvtype_proc tlvprocdestopt_lst[] = { |
59fbb3a6 | 278 | #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE) |
a831f5bb MN |
279 | { |
280 | .type = IPV6_TLV_HAO, | |
281 | .func = ipv6_dest_hao, | |
282 | }, | |
283 | #endif | |
1da177e4 LT |
284 | {-1, NULL} |
285 | }; | |
286 | ||
e5bbef20 | 287 | static int ipv6_destopt_rcv(struct sk_buff *skb) |
1da177e4 | 288 | { |
1da177e4 | 289 | struct inet6_skb_parm *opt = IP6CB(skb); |
59fbb3a6 | 290 | #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE) |
a831f5bb MN |
291 | __u16 dstbuf; |
292 | #endif | |
897dc80b | 293 | struct dst_entry *dst = skb_dst(skb); |
1da177e4 | 294 | |
ea2ae17d ACM |
295 | if (!pskb_may_pull(skb, skb_transport_offset(skb) + 8) || |
296 | !pskb_may_pull(skb, (skb_transport_offset(skb) + | |
9c70220b | 297 | ((skb_transport_header(skb)[1] + 1) << 3)))) { |
897dc80b | 298 | IP6_INC_STATS_BH(dev_net(dst->dev), ip6_dst_idev(dst), |
a11d206d | 299 | IPSTATS_MIB_INHDRERRORS); |
1da177e4 LT |
300 | kfree_skb(skb); |
301 | return -1; | |
302 | } | |
303 | ||
cfe1fc77 | 304 | opt->lastopt = opt->dst1 = skb_network_header_len(skb); |
59fbb3a6 | 305 | #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE) |
a831f5bb MN |
306 | dstbuf = opt->dst1; |
307 | #endif | |
1da177e4 | 308 | |
e5bbef20 | 309 | if (ip6_parse_tlv(tlvprocdestopt_lst, skb)) { |
b0e380b1 | 310 | skb->transport_header += (skb_transport_header(skb)[1] + 1) << 3; |
dc435e6d | 311 | opt = IP6CB(skb); |
59fbb3a6 | 312 | #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE) |
a831f5bb MN |
313 | opt->nhoff = dstbuf; |
314 | #else | |
951dbc8a | 315 | opt->nhoff = opt->dst1; |
a831f5bb | 316 | #endif |
1da177e4 LT |
317 | return 1; |
318 | } | |
319 | ||
483a47d2 DL |
320 | IP6_INC_STATS_BH(dev_net(dst->dev), |
321 | ip6_dst_idev(dst), IPSTATS_MIB_INHDRERRORS); | |
1da177e4 LT |
322 | return -1; |
323 | } | |
324 | ||
1da177e4 LT |
325 | /******************************** |
326 | Routing header. | |
327 | ********************************/ | |
328 | ||
f6bc7d9e | 329 | /* called with rcu_read_lock() */ |
e5bbef20 | 330 | static int ipv6_rthdr_rcv(struct sk_buff *skb) |
1da177e4 | 331 | { |
1da177e4 | 332 | struct inet6_skb_parm *opt = IP6CB(skb); |
65d4ed92 | 333 | struct in6_addr *addr = NULL; |
1da177e4 | 334 | struct in6_addr daddr; |
0bcbc926 | 335 | struct inet6_dev *idev; |
1da177e4 | 336 | int n, i; |
1da177e4 LT |
337 | struct ipv6_rt_hdr *hdr; |
338 | struct rt0_hdr *rthdr; | |
483a47d2 DL |
339 | struct net *net = dev_net(skb->dev); |
340 | int accept_source_route = net->ipv6.devconf_all->accept_source_route; | |
0bcbc926 | 341 | |
f6bc7d9e ED |
342 | idev = __in6_dev_get(skb->dev); |
343 | if (idev && accept_source_route > idev->cnf.accept_source_route) | |
344 | accept_source_route = idev->cnf.accept_source_route; | |
0bcbc926 | 345 | |
ea2ae17d ACM |
346 | if (!pskb_may_pull(skb, skb_transport_offset(skb) + 8) || |
347 | !pskb_may_pull(skb, (skb_transport_offset(skb) + | |
9c70220b | 348 | ((skb_transport_header(skb)[1] + 1) << 3)))) { |
adf30907 | 349 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), |
a11d206d | 350 | IPSTATS_MIB_INHDRERRORS); |
1da177e4 LT |
351 | kfree_skb(skb); |
352 | return -1; | |
353 | } | |
354 | ||
9c70220b | 355 | hdr = (struct ipv6_rt_hdr *)skb_transport_header(skb); |
1da177e4 | 356 | |
0660e03f | 357 | if (ipv6_addr_is_multicast(&ipv6_hdr(skb)->daddr) || |
1da177e4 | 358 | skb->pkt_type != PACKET_HOST) { |
adf30907 | 359 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), |
a11d206d | 360 | IPSTATS_MIB_INADDRERRORS); |
1da177e4 LT |
361 | kfree_skb(skb); |
362 | return -1; | |
363 | } | |
364 | ||
365 | looped_back: | |
366 | if (hdr->segments_left == 0) { | |
65d4ed92 | 367 | switch (hdr->type) { |
59fbb3a6 | 368 | #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE) |
65d4ed92 MN |
369 | case IPV6_SRCRT_TYPE_2: |
370 | /* Silently discard type 2 header unless it was | |
371 | * processed by own | |
372 | */ | |
373 | if (!addr) { | |
adf30907 | 374 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), |
a11d206d | 375 | IPSTATS_MIB_INADDRERRORS); |
65d4ed92 MN |
376 | kfree_skb(skb); |
377 | return -1; | |
378 | } | |
379 | break; | |
380 | #endif | |
381 | default: | |
382 | break; | |
383 | } | |
384 | ||
cfe1fc77 | 385 | opt->lastopt = opt->srcrt = skb_network_header_len(skb); |
b0e380b1 | 386 | skb->transport_header += (hdr->hdrlen + 1) << 3; |
1da177e4 LT |
387 | opt->dst0 = opt->dst1; |
388 | opt->dst1 = 0; | |
d56f90a7 | 389 | opt->nhoff = (&hdr->nexthdr) - skb_network_header(skb); |
1da177e4 LT |
390 | return 1; |
391 | } | |
392 | ||
65d4ed92 | 393 | switch (hdr->type) { |
59fbb3a6 | 394 | #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE) |
65d4ed92 | 395 | case IPV6_SRCRT_TYPE_2: |
c382bb9d YH |
396 | if (accept_source_route < 0) |
397 | goto unknown_rh; | |
65d4ed92 MN |
398 | /* Silently discard invalid RTH type 2 */ |
399 | if (hdr->hdrlen != 2 || hdr->segments_left != 1) { | |
adf30907 | 400 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), |
a11d206d | 401 | IPSTATS_MIB_INHDRERRORS); |
65d4ed92 MN |
402 | kfree_skb(skb); |
403 | return -1; | |
404 | } | |
405 | break; | |
406 | #endif | |
c382bb9d YH |
407 | default: |
408 | goto unknown_rh; | |
1da177e4 | 409 | } |
1da177e4 LT |
410 | |
411 | /* | |
412 | * This is the routing header forwarding algorithm from | |
413 | * RFC 2460, page 16. | |
414 | */ | |
415 | ||
416 | n = hdr->hdrlen >> 1; | |
417 | ||
418 | if (hdr->segments_left > n) { | |
adf30907 | 419 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), |
a11d206d | 420 | IPSTATS_MIB_INHDRERRORS); |
d56f90a7 ACM |
421 | icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, |
422 | ((&hdr->segments_left) - | |
423 | skb_network_header(skb))); | |
1da177e4 LT |
424 | return -1; |
425 | } | |
426 | ||
427 | /* We are about to mangle packet header. Be careful! | |
428 | Do not damage packets queued somewhere. | |
429 | */ | |
430 | if (skb_cloned(skb)) { | |
1da177e4 | 431 | /* the copy is a forwarded packet */ |
65c88466 | 432 | if (pskb_expand_head(skb, 0, 0, GFP_ATOMIC)) { |
adf30907 | 433 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), |
a11d206d YH |
434 | IPSTATS_MIB_OUTDISCARDS); |
435 | kfree_skb(skb); | |
1da177e4 LT |
436 | return -1; |
437 | } | |
65c88466 | 438 | hdr = (struct ipv6_rt_hdr *)skb_transport_header(skb); |
1da177e4 LT |
439 | } |
440 | ||
84fa7933 | 441 | if (skb->ip_summed == CHECKSUM_COMPLETE) |
1da177e4 LT |
442 | skb->ip_summed = CHECKSUM_NONE; |
443 | ||
444 | i = n - --hdr->segments_left; | |
445 | ||
446 | rthdr = (struct rt0_hdr *) hdr; | |
447 | addr = rthdr->addr; | |
448 | addr += i - 1; | |
449 | ||
65d4ed92 | 450 | switch (hdr->type) { |
59fbb3a6 | 451 | #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE) |
65d4ed92 MN |
452 | case IPV6_SRCRT_TYPE_2: |
453 | if (xfrm6_input_addr(skb, (xfrm_address_t *)addr, | |
0660e03f | 454 | (xfrm_address_t *)&ipv6_hdr(skb)->saddr, |
65d4ed92 | 455 | IPPROTO_ROUTING) < 0) { |
adf30907 | 456 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), |
a11d206d | 457 | IPSTATS_MIB_INADDRERRORS); |
65d4ed92 MN |
458 | kfree_skb(skb); |
459 | return -1; | |
460 | } | |
adf30907 ED |
461 | if (!ipv6_chk_home_addr(dev_net(skb_dst(skb)->dev), addr)) { |
462 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), | |
a11d206d | 463 | IPSTATS_MIB_INADDRERRORS); |
65d4ed92 MN |
464 | kfree_skb(skb); |
465 | return -1; | |
466 | } | |
467 | break; | |
468 | #endif | |
469 | default: | |
470 | break; | |
471 | } | |
472 | ||
1da177e4 | 473 | if (ipv6_addr_is_multicast(addr)) { |
adf30907 | 474 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), |
a11d206d | 475 | IPSTATS_MIB_INADDRERRORS); |
1da177e4 LT |
476 | kfree_skb(skb); |
477 | return -1; | |
478 | } | |
479 | ||
4e3fd7a0 AD |
480 | daddr = *addr; |
481 | *addr = ipv6_hdr(skb)->daddr; | |
482 | ipv6_hdr(skb)->daddr = daddr; | |
1da177e4 | 483 | |
adf30907 | 484 | skb_dst_drop(skb); |
1da177e4 | 485 | ip6_route_input(skb); |
adf30907 | 486 | if (skb_dst(skb)->error) { |
d56f90a7 | 487 | skb_push(skb, skb->data - skb_network_header(skb)); |
1da177e4 LT |
488 | dst_input(skb); |
489 | return -1; | |
490 | } | |
491 | ||
adf30907 | 492 | if (skb_dst(skb)->dev->flags&IFF_LOOPBACK) { |
0660e03f | 493 | if (ipv6_hdr(skb)->hop_limit <= 1) { |
adf30907 | 494 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), |
a11d206d | 495 | IPSTATS_MIB_INHDRERRORS); |
1da177e4 | 496 | icmpv6_send(skb, ICMPV6_TIME_EXCEED, ICMPV6_EXC_HOPLIMIT, |
3ffe533c | 497 | 0); |
1da177e4 LT |
498 | kfree_skb(skb); |
499 | return -1; | |
500 | } | |
0660e03f | 501 | ipv6_hdr(skb)->hop_limit--; |
1da177e4 LT |
502 | goto looped_back; |
503 | } | |
504 | ||
d56f90a7 | 505 | skb_push(skb, skb->data - skb_network_header(skb)); |
1da177e4 LT |
506 | dst_input(skb); |
507 | return -1; | |
c382bb9d YH |
508 | |
509 | unknown_rh: | |
adf30907 | 510 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), IPSTATS_MIB_INHDRERRORS); |
c382bb9d YH |
511 | icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, |
512 | (&hdr->type) - skb_network_header(skb)); | |
513 | return -1; | |
1da177e4 LT |
514 | } |
515 | ||
41135cc8 | 516 | static const struct inet6_protocol rthdr_protocol = { |
1da177e4 | 517 | .handler = ipv6_rthdr_rcv, |
adcfc7d0 | 518 | .flags = INET6_PROTO_NOPOLICY | INET6_PROTO_GSO_EXTHDR, |
1da177e4 LT |
519 | }; |
520 | ||
41135cc8 | 521 | static const struct inet6_protocol destopt_protocol = { |
248b238d DL |
522 | .handler = ipv6_destopt_rcv, |
523 | .flags = INET6_PROTO_NOPOLICY | INET6_PROTO_GSO_EXTHDR, | |
524 | }; | |
525 | ||
41135cc8 | 526 | static const struct inet6_protocol nodata_protocol = { |
248b238d DL |
527 | .handler = dst_discard, |
528 | .flags = INET6_PROTO_NOPOLICY, | |
529 | }; | |
530 | ||
531 | int __init ipv6_exthdrs_init(void) | |
1da177e4 | 532 | { |
248b238d DL |
533 | int ret; |
534 | ||
535 | ret = inet6_add_protocol(&rthdr_protocol, IPPROTO_ROUTING); | |
536 | if (ret) | |
537 | goto out; | |
538 | ||
539 | ret = inet6_add_protocol(&destopt_protocol, IPPROTO_DSTOPTS); | |
540 | if (ret) | |
541 | goto out_rthdr; | |
542 | ||
543 | ret = inet6_add_protocol(&nodata_protocol, IPPROTO_NONE); | |
544 | if (ret) | |
545 | goto out_destopt; | |
546 | ||
547 | out: | |
548 | return ret; | |
549 | out_rthdr: | |
550 | inet6_del_protocol(&rthdr_protocol, IPPROTO_ROUTING); | |
551 | out_destopt: | |
552 | inet6_del_protocol(&destopt_protocol, IPPROTO_DSTOPTS); | |
553 | goto out; | |
1da177e4 LT |
554 | }; |
555 | ||
248b238d DL |
556 | void ipv6_exthdrs_exit(void) |
557 | { | |
558 | inet6_del_protocol(&nodata_protocol, IPPROTO_NONE); | |
559 | inet6_del_protocol(&destopt_protocol, IPPROTO_DSTOPTS); | |
560 | inet6_del_protocol(&rthdr_protocol, IPPROTO_ROUTING); | |
561 | } | |
562 | ||
1da177e4 LT |
563 | /********************************** |
564 | Hop-by-hop options. | |
565 | **********************************/ | |
566 | ||
e76b2b25 | 567 | /* |
adf30907 | 568 | * Note: we cannot rely on skb_dst(skb) before we assign it in ip6_route_input(). |
e76b2b25 YH |
569 | */ |
570 | static inline struct inet6_dev *ipv6_skb_idev(struct sk_buff *skb) | |
571 | { | |
adf30907 | 572 | return skb_dst(skb) ? ip6_dst_idev(skb_dst(skb)) : __in6_dev_get(skb->dev); |
e76b2b25 YH |
573 | } |
574 | ||
2570a4f5 DM |
575 | static inline struct net *ipv6_skb_net(struct sk_buff *skb) |
576 | { | |
577 | return skb_dst(skb) ? dev_net(skb_dst(skb)->dev) : dev_net(skb->dev); | |
578 | } | |
579 | ||
1da177e4 LT |
580 | /* Router Alert as of RFC 2711 */ |
581 | ||
e5bbef20 | 582 | static int ipv6_hop_ra(struct sk_buff *skb, int optoff) |
1da177e4 | 583 | { |
d56f90a7 | 584 | const unsigned char *nh = skb_network_header(skb); |
a80ff03e | 585 | |
d56f90a7 | 586 | if (nh[optoff + 1] == 2) { |
1da177e4 LT |
587 | IP6CB(skb)->ra = optoff; |
588 | return 1; | |
589 | } | |
64ce2073 | 590 | LIMIT_NETDEBUG(KERN_DEBUG "ipv6_hop_ra: wrong RA length %d\n", |
d56f90a7 | 591 | nh[optoff + 1]); |
1da177e4 LT |
592 | kfree_skb(skb); |
593 | return 0; | |
594 | } | |
595 | ||
596 | /* Jumbo payload */ | |
597 | ||
e5bbef20 | 598 | static int ipv6_hop_jumbo(struct sk_buff *skb, int optoff) |
1da177e4 | 599 | { |
d56f90a7 | 600 | const unsigned char *nh = skb_network_header(skb); |
2570a4f5 | 601 | struct net *net = ipv6_skb_net(skb); |
1da177e4 LT |
602 | u32 pkt_len; |
603 | ||
d56f90a7 | 604 | if (nh[optoff + 1] != 4 || (optoff & 3) != 2) { |
64ce2073 | 605 | LIMIT_NETDEBUG(KERN_DEBUG "ipv6_hop_jumbo: wrong jumbo opt length/alignment %d\n", |
d56f90a7 | 606 | nh[optoff+1]); |
483a47d2 | 607 | IP6_INC_STATS_BH(net, ipv6_skb_idev(skb), |
a11d206d | 608 | IPSTATS_MIB_INHDRERRORS); |
1da177e4 LT |
609 | goto drop; |
610 | } | |
611 | ||
d56f90a7 | 612 | pkt_len = ntohl(*(__be32 *)(nh + optoff + 2)); |
1da177e4 | 613 | if (pkt_len <= IPV6_MAXPLEN) { |
483a47d2 DL |
614 | IP6_INC_STATS_BH(net, ipv6_skb_idev(skb), |
615 | IPSTATS_MIB_INHDRERRORS); | |
1da177e4 LT |
616 | icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, optoff+2); |
617 | return 0; | |
618 | } | |
0660e03f | 619 | if (ipv6_hdr(skb)->payload_len) { |
483a47d2 DL |
620 | IP6_INC_STATS_BH(net, ipv6_skb_idev(skb), |
621 | IPSTATS_MIB_INHDRERRORS); | |
1da177e4 LT |
622 | icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, optoff); |
623 | return 0; | |
624 | } | |
625 | ||
626 | if (pkt_len > skb->len - sizeof(struct ipv6hdr)) { | |
483a47d2 DL |
627 | IP6_INC_STATS_BH(net, ipv6_skb_idev(skb), |
628 | IPSTATS_MIB_INTRUNCATEDPKTS); | |
1da177e4 LT |
629 | goto drop; |
630 | } | |
42ca89c1 SH |
631 | |
632 | if (pskb_trim_rcsum(skb, pkt_len + sizeof(struct ipv6hdr))) | |
633 | goto drop; | |
634 | ||
1da177e4 LT |
635 | return 1; |
636 | ||
637 | drop: | |
638 | kfree_skb(skb); | |
639 | return 0; | |
640 | } | |
641 | ||
642 | static struct tlvtype_proc tlvprochopopt_lst[] = { | |
643 | { | |
644 | .type = IPV6_TLV_ROUTERALERT, | |
645 | .func = ipv6_hop_ra, | |
646 | }, | |
647 | { | |
648 | .type = IPV6_TLV_JUMBO, | |
649 | .func = ipv6_hop_jumbo, | |
650 | }, | |
651 | { -1, } | |
652 | }; | |
653 | ||
e5bbef20 | 654 | int ipv6_parse_hopopts(struct sk_buff *skb) |
1da177e4 | 655 | { |
951dbc8a PM |
656 | struct inet6_skb_parm *opt = IP6CB(skb); |
657 | ||
ec670095 | 658 | /* |
d56f90a7 | 659 | * skb_network_header(skb) is equal to skb->data, and |
cfe1fc77 | 660 | * skb_network_header_len(skb) is always equal to |
ec670095 YH |
661 | * sizeof(struct ipv6hdr) by definition of |
662 | * hop-by-hop options. | |
663 | */ | |
664 | if (!pskb_may_pull(skb, sizeof(struct ipv6hdr) + 8) || | |
9c70220b ACM |
665 | !pskb_may_pull(skb, (sizeof(struct ipv6hdr) + |
666 | ((skb_transport_header(skb)[1] + 1) << 3)))) { | |
ec670095 YH |
667 | kfree_skb(skb); |
668 | return -1; | |
669 | } | |
670 | ||
951dbc8a | 671 | opt->hop = sizeof(struct ipv6hdr); |
e5bbef20 | 672 | if (ip6_parse_tlv(tlvprochopopt_lst, skb)) { |
b0e380b1 | 673 | skb->transport_header += (skb_transport_header(skb)[1] + 1) << 3; |
dc435e6d | 674 | opt = IP6CB(skb); |
951dbc8a | 675 | opt->nhoff = sizeof(struct ipv6hdr); |
b809739a | 676 | return 1; |
951dbc8a | 677 | } |
1da177e4 LT |
678 | return -1; |
679 | } | |
680 | ||
681 | /* | |
682 | * Creating outbound headers. | |
683 | * | |
684 | * "build" functions work when skb is filled from head to tail (datagram) | |
685 | * "push" functions work when headers are added from tail to head (tcp) | |
686 | * | |
687 | * In both cases we assume, that caller reserved enough room | |
688 | * for headers. | |
689 | */ | |
690 | ||
691 | static void ipv6_push_rthdr(struct sk_buff *skb, u8 *proto, | |
692 | struct ipv6_rt_hdr *opt, | |
693 | struct in6_addr **addr_p) | |
694 | { | |
695 | struct rt0_hdr *phdr, *ihdr; | |
696 | int hops; | |
697 | ||
698 | ihdr = (struct rt0_hdr *) opt; | |
1ab1457c | 699 | |
1da177e4 LT |
700 | phdr = (struct rt0_hdr *) skb_push(skb, (ihdr->rt_hdr.hdrlen + 1) << 3); |
701 | memcpy(phdr, ihdr, sizeof(struct rt0_hdr)); | |
702 | ||
703 | hops = ihdr->rt_hdr.hdrlen >> 1; | |
704 | ||
705 | if (hops > 1) | |
706 | memcpy(phdr->addr, ihdr->addr + 1, | |
707 | (hops - 1) * sizeof(struct in6_addr)); | |
708 | ||
4e3fd7a0 | 709 | phdr->addr[hops - 1] = **addr_p; |
1da177e4 LT |
710 | *addr_p = ihdr->addr; |
711 | ||
712 | phdr->rt_hdr.nexthdr = *proto; | |
713 | *proto = NEXTHDR_ROUTING; | |
714 | } | |
715 | ||
716 | static void ipv6_push_exthdr(struct sk_buff *skb, u8 *proto, u8 type, struct ipv6_opt_hdr *opt) | |
717 | { | |
718 | struct ipv6_opt_hdr *h = (struct ipv6_opt_hdr *)skb_push(skb, ipv6_optlen(opt)); | |
719 | ||
720 | memcpy(h, opt, ipv6_optlen(opt)); | |
721 | h->nexthdr = *proto; | |
722 | *proto = type; | |
723 | } | |
724 | ||
725 | void ipv6_push_nfrag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt, | |
726 | u8 *proto, | |
727 | struct in6_addr **daddr) | |
728 | { | |
333fad53 | 729 | if (opt->srcrt) { |
1da177e4 | 730 | ipv6_push_rthdr(skb, proto, opt->srcrt, daddr); |
333fad53 YH |
731 | /* |
732 | * IPV6_RTHDRDSTOPTS is ignored | |
733 | * unless IPV6_RTHDR is set (RFC3542). | |
734 | */ | |
735 | if (opt->dst0opt) | |
736 | ipv6_push_exthdr(skb, proto, NEXTHDR_DEST, opt->dst0opt); | |
737 | } | |
1da177e4 LT |
738 | if (opt->hopopt) |
739 | ipv6_push_exthdr(skb, proto, NEXTHDR_HOP, opt->hopopt); | |
740 | } | |
7159039a YH |
741 | EXPORT_SYMBOL(ipv6_push_nfrag_opts); |
742 | ||
1da177e4 LT |
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) { | |
ac3c8172 | 756 | long dif = (char *)opt2 - (char *)opt; |
1da177e4 LT |
757 | memcpy(opt2, opt, opt->tot_len); |
758 | if (opt2->hopopt) | |
ac3c8172 | 759 | *((char **)&opt2->hopopt) += dif; |
1da177e4 | 760 | if (opt2->dst0opt) |
ac3c8172 | 761 | *((char **)&opt2->dst0opt) += dif; |
1da177e4 | 762 | if (opt2->dst1opt) |
ac3c8172 | 763 | *((char **)&opt2->dst1opt) += dif; |
1da177e4 | 764 | if (opt2->srcrt) |
ac3c8172 | 765 | *((char **)&opt2->srcrt) += dif; |
1da177e4 LT |
766 | } |
767 | return opt2; | |
768 | } | |
3cf3dc6c ACM |
769 | EXPORT_SYMBOL_GPL(ipv6_dup_options); |
770 | ||
333fad53 YH |
771 | static int ipv6_renew_option(void *ohdr, |
772 | struct ipv6_opt_hdr __user *newopt, int newoptlen, | |
773 | int inherit, | |
774 | struct ipv6_opt_hdr **hdr, | |
775 | char **p) | |
776 | { | |
777 | if (inherit) { | |
778 | if (ohdr) { | |
779 | memcpy(*p, ohdr, ipv6_optlen((struct ipv6_opt_hdr *)ohdr)); | |
780 | *hdr = (struct ipv6_opt_hdr *)*p; | |
781 | *p += CMSG_ALIGN(ipv6_optlen(*(struct ipv6_opt_hdr **)hdr)); | |
782 | } | |
783 | } else { | |
784 | if (newopt) { | |
785 | if (copy_from_user(*p, newopt, newoptlen)) | |
786 | return -EFAULT; | |
787 | *hdr = (struct ipv6_opt_hdr *)*p; | |
788 | if (ipv6_optlen(*(struct ipv6_opt_hdr **)hdr) > newoptlen) | |
789 | return -EINVAL; | |
790 | *p += CMSG_ALIGN(newoptlen); | |
791 | } | |
792 | } | |
793 | return 0; | |
794 | } | |
795 | ||
796 | struct ipv6_txoptions * | |
797 | ipv6_renew_options(struct sock *sk, struct ipv6_txoptions *opt, | |
798 | int newtype, | |
799 | struct ipv6_opt_hdr __user *newopt, int newoptlen) | |
800 | { | |
801 | int tot_len = 0; | |
802 | char *p; | |
803 | struct ipv6_txoptions *opt2; | |
804 | int err; | |
805 | ||
99c7bc01 YH |
806 | if (opt) { |
807 | if (newtype != IPV6_HOPOPTS && opt->hopopt) | |
808 | tot_len += CMSG_ALIGN(ipv6_optlen(opt->hopopt)); | |
809 | if (newtype != IPV6_RTHDRDSTOPTS && opt->dst0opt) | |
810 | tot_len += CMSG_ALIGN(ipv6_optlen(opt->dst0opt)); | |
811 | if (newtype != IPV6_RTHDR && opt->srcrt) | |
812 | tot_len += CMSG_ALIGN(ipv6_optlen(opt->srcrt)); | |
813 | if (newtype != IPV6_DSTOPTS && opt->dst1opt) | |
814 | tot_len += CMSG_ALIGN(ipv6_optlen(opt->dst1opt)); | |
815 | } | |
816 | ||
333fad53 YH |
817 | if (newopt && newoptlen) |
818 | tot_len += CMSG_ALIGN(newoptlen); | |
819 | ||
820 | if (!tot_len) | |
821 | return NULL; | |
822 | ||
8b8aa4b5 | 823 | tot_len += sizeof(*opt2); |
333fad53 YH |
824 | opt2 = sock_kmalloc(sk, tot_len, GFP_ATOMIC); |
825 | if (!opt2) | |
826 | return ERR_PTR(-ENOBUFS); | |
827 | ||
828 | memset(opt2, 0, tot_len); | |
829 | ||
830 | opt2->tot_len = tot_len; | |
831 | p = (char *)(opt2 + 1); | |
832 | ||
99c7bc01 | 833 | err = ipv6_renew_option(opt ? opt->hopopt : NULL, newopt, newoptlen, |
333fad53 YH |
834 | newtype != IPV6_HOPOPTS, |
835 | &opt2->hopopt, &p); | |
836 | if (err) | |
837 | goto out; | |
838 | ||
99c7bc01 | 839 | err = ipv6_renew_option(opt ? opt->dst0opt : NULL, newopt, newoptlen, |
333fad53 YH |
840 | newtype != IPV6_RTHDRDSTOPTS, |
841 | &opt2->dst0opt, &p); | |
842 | if (err) | |
843 | goto out; | |
844 | ||
99c7bc01 | 845 | err = ipv6_renew_option(opt ? opt->srcrt : NULL, newopt, newoptlen, |
333fad53 | 846 | newtype != IPV6_RTHDR, |
99c7bc01 | 847 | (struct ipv6_opt_hdr **)&opt2->srcrt, &p); |
333fad53 YH |
848 | if (err) |
849 | goto out; | |
850 | ||
99c7bc01 | 851 | err = ipv6_renew_option(opt ? opt->dst1opt : NULL, newopt, newoptlen, |
333fad53 YH |
852 | newtype != IPV6_DSTOPTS, |
853 | &opt2->dst1opt, &p); | |
854 | if (err) | |
855 | goto out; | |
856 | ||
857 | opt2->opt_nflen = (opt2->hopopt ? ipv6_optlen(opt2->hopopt) : 0) + | |
858 | (opt2->dst0opt ? ipv6_optlen(opt2->dst0opt) : 0) + | |
859 | (opt2->srcrt ? ipv6_optlen(opt2->srcrt) : 0); | |
860 | opt2->opt_flen = (opt2->dst1opt ? ipv6_optlen(opt2->dst1opt) : 0); | |
861 | ||
862 | return opt2; | |
863 | out: | |
8b8aa4b5 | 864 | sock_kfree_s(sk, opt2, opt2->tot_len); |
333fad53 YH |
865 | return ERR_PTR(err); |
866 | } | |
867 | ||
df9890c3 YH |
868 | struct ipv6_txoptions *ipv6_fixup_options(struct ipv6_txoptions *opt_space, |
869 | struct ipv6_txoptions *opt) | |
870 | { | |
871 | /* | |
872 | * ignore the dest before srcrt unless srcrt is being included. | |
873 | * --yoshfuji | |
874 | */ | |
875 | if (opt && opt->dst0opt && !opt->srcrt) { | |
876 | if (opt_space != opt) { | |
877 | memcpy(opt_space, opt, sizeof(*opt_space)); | |
878 | opt = opt_space; | |
879 | } | |
880 | opt->opt_nflen -= ipv6_optlen(opt->dst0opt); | |
881 | opt->dst0opt = NULL; | |
882 | } | |
883 | ||
884 | return opt; | |
885 | } | |
a495f836 | 886 | EXPORT_SYMBOL_GPL(ipv6_fixup_options); |
df9890c3 | 887 | |
20c59de2 AE |
888 | /** |
889 | * fl6_update_dst - update flowi destination address with info given | |
890 | * by srcrt option, if any. | |
891 | * | |
4c9483b2 | 892 | * @fl6: flowi6 for which daddr is to be updated |
20c59de2 | 893 | * @opt: struct ipv6_txoptions in which to look for srcrt opt |
4c9483b2 | 894 | * @orig: copy of original daddr address if modified |
20c59de2 AE |
895 | * |
896 | * Returns NULL if no txoptions or no srcrt, otherwise returns orig | |
4c9483b2 | 897 | * and initial value of fl6->daddr set in orig |
20c59de2 | 898 | */ |
4c9483b2 | 899 | struct in6_addr *fl6_update_dst(struct flowi6 *fl6, |
20c59de2 AE |
900 | const struct ipv6_txoptions *opt, |
901 | struct in6_addr *orig) | |
902 | { | |
903 | if (!opt || !opt->srcrt) | |
904 | return NULL; | |
905 | ||
4e3fd7a0 AD |
906 | *orig = fl6->daddr; |
907 | fl6->daddr = *((struct rt0_hdr *)opt->srcrt)->addr; | |
20c59de2 AE |
908 | return orig; |
909 | } | |
20c59de2 | 910 | EXPORT_SYMBOL_GPL(fl6_update_dst); |