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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> | |
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> | |
07a93626 | 46 | #if IS_ENABLED(CONFIG_IPV6_MIP6) |
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 | * | |
a50feda5 ED |
99 | * Parsing function "func" returns true, if parsing succeed |
100 | * and false, if it failed. | |
1da177e4 LT |
101 | * It MUST NOT touch skb->h. |
102 | */ | |
103 | ||
104 | struct tlvtype_proc { | |
105 | int type; | |
a50feda5 | 106 | bool (*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 | ||
a50feda5 | 115 | static bool ip6_tlvopt_unknown(struct sk_buff *skb, int optoff) |
1da177e4 | 116 | { |
d56f90a7 | 117 | switch ((skb_network_header(skb)[optoff] & 0xC0) >> 6) { |
1da177e4 | 118 | case 0: /* ignore */ |
a50feda5 | 119 | return true; |
1da177e4 LT |
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); | |
a50feda5 | 132 | return false; |
3ff50b79 | 133 | } |
1da177e4 LT |
134 | |
135 | kfree_skb(skb); | |
a50feda5 | 136 | return false; |
1da177e4 LT |
137 | } |
138 | ||
139 | /* Parse tlv encoded option header (hop-by-hop or destination) */ | |
140 | ||
a50feda5 | 141 | static bool ip6_parse_tlv(const struct tlvtype_proc *procs, struct sk_buff *skb) |
1da177e4 | 142 | { |
a50feda5 | 143 | const 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; |
9b905fe6 | 147 | int padlen = 0; |
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; |
c1412fce | 157 | int i; |
1da177e4 | 158 | |
d56f90a7 | 159 | switch (nh[off]) { |
1de5a71c | 160 | case IPV6_TLV_PAD1: |
1da177e4 | 161 | optlen = 1; |
9b905fe6 EZ |
162 | padlen++; |
163 | if (padlen > 7) | |
164 | goto bad; | |
1da177e4 LT |
165 | break; |
166 | ||
167 | case IPV6_TLV_PADN: | |
c1412fce EZ |
168 | /* RFC 2460 states that the purpose of PadN is |
169 | * to align the containing header to multiples | |
170 | * of 8. 7 is therefore the highest valid value. | |
171 | * See also RFC 4942, Section 2.1.9.5. | |
172 | */ | |
9b905fe6 EZ |
173 | padlen += optlen; |
174 | if (padlen > 7) | |
c1412fce EZ |
175 | goto bad; |
176 | /* RFC 4942 recommends receiving hosts to | |
177 | * actively check PadN payload to contain | |
178 | * only zeroes. | |
179 | */ | |
180 | for (i = 2; i < optlen; i++) { | |
181 | if (nh[off + i] != 0) | |
182 | goto bad; | |
183 | } | |
1da177e4 LT |
184 | break; |
185 | ||
186 | default: /* Other TLV code so scan list */ | |
187 | if (optlen > len) | |
188 | goto bad; | |
189 | for (curr=procs; curr->type >= 0; curr++) { | |
d56f90a7 | 190 | if (curr->type == nh[off]) { |
1ab1457c YH |
191 | /* type specific length/alignment |
192 | checks will be performed in the | |
1da177e4 | 193 | func(). */ |
a50feda5 ED |
194 | if (curr->func(skb, off) == false) |
195 | return false; | |
1da177e4 LT |
196 | break; |
197 | } | |
198 | } | |
199 | if (curr->type < 0) { | |
e5bbef20 | 200 | if (ip6_tlvopt_unknown(skb, off) == 0) |
a50feda5 | 201 | return false; |
1da177e4 | 202 | } |
9b905fe6 | 203 | padlen = 0; |
1da177e4 LT |
204 | break; |
205 | } | |
206 | off += optlen; | |
207 | len -= optlen; | |
208 | } | |
9b905fe6 EZ |
209 | /* This case will not be caught by above check since its padding |
210 | * length is smaller than 7: | |
211 | * 1 byte NH + 1 byte Length + 6 bytes Padding | |
212 | */ | |
213 | if ((padlen == 6) && ((off - skb_network_header_len(skb)) == 8)) | |
214 | goto bad; | |
215 | ||
1da177e4 | 216 | if (len == 0) |
a50feda5 | 217 | return true; |
1da177e4 LT |
218 | bad: |
219 | kfree_skb(skb); | |
a50feda5 | 220 | return false; |
1da177e4 LT |
221 | } |
222 | ||
223 | /***************************** | |
224 | Destination options header. | |
225 | *****************************/ | |
226 | ||
07a93626 | 227 | #if IS_ENABLED(CONFIG_IPV6_MIP6) |
a50feda5 | 228 | static bool ipv6_dest_hao(struct sk_buff *skb, int optoff) |
a831f5bb | 229 | { |
a831f5bb MN |
230 | struct ipv6_destopt_hao *hao; |
231 | struct inet6_skb_parm *opt = IP6CB(skb); | |
0660e03f | 232 | struct ipv6hdr *ipv6h = ipv6_hdr(skb); |
a831f5bb MN |
233 | struct in6_addr tmp_addr; |
234 | int ret; | |
235 | ||
236 | if (opt->dsthao) { | |
237 | LIMIT_NETDEBUG(KERN_DEBUG "hao duplicated\n"); | |
238 | goto discard; | |
239 | } | |
240 | opt->dsthao = opt->dst1; | |
241 | opt->dst1 = 0; | |
242 | ||
d56f90a7 | 243 | hao = (struct ipv6_destopt_hao *)(skb_network_header(skb) + optoff); |
a831f5bb MN |
244 | |
245 | if (hao->length != 16) { | |
246 | LIMIT_NETDEBUG( | |
247 | KERN_DEBUG "hao invalid option length = %d\n", hao->length); | |
248 | goto discard; | |
249 | } | |
250 | ||
251 | if (!(ipv6_addr_type(&hao->addr) & IPV6_ADDR_UNICAST)) { | |
252 | LIMIT_NETDEBUG( | |
5b095d98 | 253 | KERN_DEBUG "hao is not an unicast addr: %pI6\n", &hao->addr); |
a831f5bb MN |
254 | goto discard; |
255 | } | |
256 | ||
257 | ret = xfrm6_input_addr(skb, (xfrm_address_t *)&ipv6h->daddr, | |
258 | (xfrm_address_t *)&hao->addr, IPPROTO_DSTOPTS); | |
259 | if (unlikely(ret < 0)) | |
260 | goto discard; | |
261 | ||
262 | if (skb_cloned(skb)) { | |
65c88466 | 263 | if (pskb_expand_head(skb, 0, 0, GFP_ATOMIC)) |
a831f5bb MN |
264 | goto discard; |
265 | ||
a831f5bb | 266 | /* update all variable using below by copied skbuff */ |
65c88466 | 267 | hao = (struct ipv6_destopt_hao *)(skb_network_header(skb) + |
d56f90a7 | 268 | optoff); |
65c88466 | 269 | ipv6h = ipv6_hdr(skb); |
a831f5bb MN |
270 | } |
271 | ||
272 | if (skb->ip_summed == CHECKSUM_COMPLETE) | |
273 | skb->ip_summed = CHECKSUM_NONE; | |
274 | ||
4e3fd7a0 AD |
275 | tmp_addr = ipv6h->saddr; |
276 | ipv6h->saddr = hao->addr; | |
277 | hao->addr = tmp_addr; | |
a831f5bb | 278 | |
b7aa0bf7 | 279 | if (skb->tstamp.tv64 == 0) |
a831f5bb MN |
280 | __net_timestamp(skb); |
281 | ||
a50feda5 | 282 | return true; |
a831f5bb MN |
283 | |
284 | discard: | |
285 | kfree_skb(skb); | |
a50feda5 | 286 | return false; |
a831f5bb MN |
287 | } |
288 | #endif | |
289 | ||
a50feda5 | 290 | static const struct tlvtype_proc tlvprocdestopt_lst[] = { |
07a93626 | 291 | #if IS_ENABLED(CONFIG_IPV6_MIP6) |
a831f5bb MN |
292 | { |
293 | .type = IPV6_TLV_HAO, | |
294 | .func = ipv6_dest_hao, | |
295 | }, | |
296 | #endif | |
1da177e4 LT |
297 | {-1, NULL} |
298 | }; | |
299 | ||
e5bbef20 | 300 | static int ipv6_destopt_rcv(struct sk_buff *skb) |
1da177e4 | 301 | { |
1da177e4 | 302 | struct inet6_skb_parm *opt = IP6CB(skb); |
07a93626 | 303 | #if IS_ENABLED(CONFIG_IPV6_MIP6) |
a831f5bb MN |
304 | __u16 dstbuf; |
305 | #endif | |
897dc80b | 306 | struct dst_entry *dst = skb_dst(skb); |
1da177e4 | 307 | |
ea2ae17d ACM |
308 | if (!pskb_may_pull(skb, skb_transport_offset(skb) + 8) || |
309 | !pskb_may_pull(skb, (skb_transport_offset(skb) + | |
9c70220b | 310 | ((skb_transport_header(skb)[1] + 1) << 3)))) { |
897dc80b | 311 | IP6_INC_STATS_BH(dev_net(dst->dev), ip6_dst_idev(dst), |
a11d206d | 312 | IPSTATS_MIB_INHDRERRORS); |
1da177e4 LT |
313 | kfree_skb(skb); |
314 | return -1; | |
315 | } | |
316 | ||
cfe1fc77 | 317 | opt->lastopt = opt->dst1 = skb_network_header_len(skb); |
07a93626 | 318 | #if IS_ENABLED(CONFIG_IPV6_MIP6) |
a831f5bb MN |
319 | dstbuf = opt->dst1; |
320 | #endif | |
1da177e4 | 321 | |
e5bbef20 | 322 | if (ip6_parse_tlv(tlvprocdestopt_lst, skb)) { |
b0e380b1 | 323 | skb->transport_header += (skb_transport_header(skb)[1] + 1) << 3; |
dc435e6d | 324 | opt = IP6CB(skb); |
07a93626 | 325 | #if IS_ENABLED(CONFIG_IPV6_MIP6) |
a831f5bb MN |
326 | opt->nhoff = dstbuf; |
327 | #else | |
951dbc8a | 328 | opt->nhoff = opt->dst1; |
a831f5bb | 329 | #endif |
1da177e4 LT |
330 | return 1; |
331 | } | |
332 | ||
483a47d2 DL |
333 | IP6_INC_STATS_BH(dev_net(dst->dev), |
334 | ip6_dst_idev(dst), IPSTATS_MIB_INHDRERRORS); | |
1da177e4 LT |
335 | return -1; |
336 | } | |
337 | ||
1da177e4 LT |
338 | /******************************** |
339 | Routing header. | |
340 | ********************************/ | |
341 | ||
f6bc7d9e | 342 | /* called with rcu_read_lock() */ |
e5bbef20 | 343 | static int ipv6_rthdr_rcv(struct sk_buff *skb) |
1da177e4 | 344 | { |
1da177e4 | 345 | struct inet6_skb_parm *opt = IP6CB(skb); |
65d4ed92 | 346 | struct in6_addr *addr = NULL; |
1da177e4 | 347 | struct in6_addr daddr; |
0bcbc926 | 348 | struct inet6_dev *idev; |
1da177e4 | 349 | int n, i; |
1da177e4 LT |
350 | struct ipv6_rt_hdr *hdr; |
351 | struct rt0_hdr *rthdr; | |
483a47d2 DL |
352 | struct net *net = dev_net(skb->dev); |
353 | int accept_source_route = net->ipv6.devconf_all->accept_source_route; | |
0bcbc926 | 354 | |
f6bc7d9e ED |
355 | idev = __in6_dev_get(skb->dev); |
356 | if (idev && accept_source_route > idev->cnf.accept_source_route) | |
357 | accept_source_route = idev->cnf.accept_source_route; | |
0bcbc926 | 358 | |
ea2ae17d ACM |
359 | if (!pskb_may_pull(skb, skb_transport_offset(skb) + 8) || |
360 | !pskb_may_pull(skb, (skb_transport_offset(skb) + | |
9c70220b | 361 | ((skb_transport_header(skb)[1] + 1) << 3)))) { |
adf30907 | 362 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), |
a11d206d | 363 | IPSTATS_MIB_INHDRERRORS); |
1da177e4 LT |
364 | kfree_skb(skb); |
365 | return -1; | |
366 | } | |
367 | ||
9c70220b | 368 | hdr = (struct ipv6_rt_hdr *)skb_transport_header(skb); |
1da177e4 | 369 | |
0660e03f | 370 | if (ipv6_addr_is_multicast(&ipv6_hdr(skb)->daddr) || |
1da177e4 | 371 | skb->pkt_type != PACKET_HOST) { |
adf30907 | 372 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), |
a11d206d | 373 | IPSTATS_MIB_INADDRERRORS); |
1da177e4 LT |
374 | kfree_skb(skb); |
375 | return -1; | |
376 | } | |
377 | ||
378 | looped_back: | |
379 | if (hdr->segments_left == 0) { | |
65d4ed92 | 380 | switch (hdr->type) { |
07a93626 | 381 | #if IS_ENABLED(CONFIG_IPV6_MIP6) |
65d4ed92 MN |
382 | case IPV6_SRCRT_TYPE_2: |
383 | /* Silently discard type 2 header unless it was | |
384 | * processed by own | |
385 | */ | |
386 | if (!addr) { | |
adf30907 | 387 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), |
a11d206d | 388 | IPSTATS_MIB_INADDRERRORS); |
65d4ed92 MN |
389 | kfree_skb(skb); |
390 | return -1; | |
391 | } | |
392 | break; | |
393 | #endif | |
394 | default: | |
395 | break; | |
396 | } | |
397 | ||
cfe1fc77 | 398 | opt->lastopt = opt->srcrt = skb_network_header_len(skb); |
b0e380b1 | 399 | skb->transport_header += (hdr->hdrlen + 1) << 3; |
1da177e4 LT |
400 | opt->dst0 = opt->dst1; |
401 | opt->dst1 = 0; | |
d56f90a7 | 402 | opt->nhoff = (&hdr->nexthdr) - skb_network_header(skb); |
1da177e4 LT |
403 | return 1; |
404 | } | |
405 | ||
65d4ed92 | 406 | switch (hdr->type) { |
07a93626 | 407 | #if IS_ENABLED(CONFIG_IPV6_MIP6) |
65d4ed92 | 408 | case IPV6_SRCRT_TYPE_2: |
c382bb9d YH |
409 | if (accept_source_route < 0) |
410 | goto unknown_rh; | |
65d4ed92 MN |
411 | /* Silently discard invalid RTH type 2 */ |
412 | if (hdr->hdrlen != 2 || hdr->segments_left != 1) { | |
adf30907 | 413 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), |
a11d206d | 414 | IPSTATS_MIB_INHDRERRORS); |
65d4ed92 MN |
415 | kfree_skb(skb); |
416 | return -1; | |
417 | } | |
418 | break; | |
419 | #endif | |
c382bb9d YH |
420 | default: |
421 | goto unknown_rh; | |
1da177e4 | 422 | } |
1da177e4 LT |
423 | |
424 | /* | |
425 | * This is the routing header forwarding algorithm from | |
426 | * RFC 2460, page 16. | |
427 | */ | |
428 | ||
429 | n = hdr->hdrlen >> 1; | |
430 | ||
431 | if (hdr->segments_left > n) { | |
adf30907 | 432 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), |
a11d206d | 433 | IPSTATS_MIB_INHDRERRORS); |
d56f90a7 ACM |
434 | icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, |
435 | ((&hdr->segments_left) - | |
436 | skb_network_header(skb))); | |
1da177e4 LT |
437 | return -1; |
438 | } | |
439 | ||
440 | /* We are about to mangle packet header. Be careful! | |
441 | Do not damage packets queued somewhere. | |
442 | */ | |
443 | if (skb_cloned(skb)) { | |
1da177e4 | 444 | /* the copy is a forwarded packet */ |
65c88466 | 445 | if (pskb_expand_head(skb, 0, 0, GFP_ATOMIC)) { |
adf30907 | 446 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), |
a11d206d YH |
447 | IPSTATS_MIB_OUTDISCARDS); |
448 | kfree_skb(skb); | |
1da177e4 LT |
449 | return -1; |
450 | } | |
65c88466 | 451 | hdr = (struct ipv6_rt_hdr *)skb_transport_header(skb); |
1da177e4 LT |
452 | } |
453 | ||
84fa7933 | 454 | if (skb->ip_summed == CHECKSUM_COMPLETE) |
1da177e4 LT |
455 | skb->ip_summed = CHECKSUM_NONE; |
456 | ||
457 | i = n - --hdr->segments_left; | |
458 | ||
459 | rthdr = (struct rt0_hdr *) hdr; | |
460 | addr = rthdr->addr; | |
461 | addr += i - 1; | |
462 | ||
65d4ed92 | 463 | switch (hdr->type) { |
07a93626 | 464 | #if IS_ENABLED(CONFIG_IPV6_MIP6) |
65d4ed92 MN |
465 | case IPV6_SRCRT_TYPE_2: |
466 | if (xfrm6_input_addr(skb, (xfrm_address_t *)addr, | |
0660e03f | 467 | (xfrm_address_t *)&ipv6_hdr(skb)->saddr, |
65d4ed92 | 468 | IPPROTO_ROUTING) < 0) { |
adf30907 | 469 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), |
a11d206d | 470 | IPSTATS_MIB_INADDRERRORS); |
65d4ed92 MN |
471 | kfree_skb(skb); |
472 | return -1; | |
473 | } | |
adf30907 ED |
474 | if (!ipv6_chk_home_addr(dev_net(skb_dst(skb)->dev), addr)) { |
475 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), | |
a11d206d | 476 | IPSTATS_MIB_INADDRERRORS); |
65d4ed92 MN |
477 | kfree_skb(skb); |
478 | return -1; | |
479 | } | |
480 | break; | |
481 | #endif | |
482 | default: | |
483 | break; | |
484 | } | |
485 | ||
1da177e4 | 486 | if (ipv6_addr_is_multicast(addr)) { |
adf30907 | 487 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), |
a11d206d | 488 | IPSTATS_MIB_INADDRERRORS); |
1da177e4 LT |
489 | kfree_skb(skb); |
490 | return -1; | |
491 | } | |
492 | ||
4e3fd7a0 AD |
493 | daddr = *addr; |
494 | *addr = ipv6_hdr(skb)->daddr; | |
495 | ipv6_hdr(skb)->daddr = daddr; | |
1da177e4 | 496 | |
adf30907 | 497 | skb_dst_drop(skb); |
1da177e4 | 498 | ip6_route_input(skb); |
adf30907 | 499 | if (skb_dst(skb)->error) { |
d56f90a7 | 500 | skb_push(skb, skb->data - skb_network_header(skb)); |
1da177e4 LT |
501 | dst_input(skb); |
502 | return -1; | |
503 | } | |
504 | ||
adf30907 | 505 | if (skb_dst(skb)->dev->flags&IFF_LOOPBACK) { |
0660e03f | 506 | if (ipv6_hdr(skb)->hop_limit <= 1) { |
adf30907 | 507 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), |
a11d206d | 508 | IPSTATS_MIB_INHDRERRORS); |
1da177e4 | 509 | icmpv6_send(skb, ICMPV6_TIME_EXCEED, ICMPV6_EXC_HOPLIMIT, |
3ffe533c | 510 | 0); |
1da177e4 LT |
511 | kfree_skb(skb); |
512 | return -1; | |
513 | } | |
0660e03f | 514 | ipv6_hdr(skb)->hop_limit--; |
1da177e4 LT |
515 | goto looped_back; |
516 | } | |
517 | ||
d56f90a7 | 518 | skb_push(skb, skb->data - skb_network_header(skb)); |
1da177e4 LT |
519 | dst_input(skb); |
520 | return -1; | |
c382bb9d YH |
521 | |
522 | unknown_rh: | |
adf30907 | 523 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), IPSTATS_MIB_INHDRERRORS); |
c382bb9d YH |
524 | icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, |
525 | (&hdr->type) - skb_network_header(skb)); | |
526 | return -1; | |
1da177e4 LT |
527 | } |
528 | ||
41135cc8 | 529 | static const struct inet6_protocol rthdr_protocol = { |
1da177e4 | 530 | .handler = ipv6_rthdr_rcv, |
adcfc7d0 | 531 | .flags = INET6_PROTO_NOPOLICY | INET6_PROTO_GSO_EXTHDR, |
1da177e4 LT |
532 | }; |
533 | ||
8ca896cf VY |
534 | static const struct net_offload rthdr_offload = { |
535 | .flags = INET6_PROTO_GSO_EXTHDR, | |
536 | }; | |
537 | ||
41135cc8 | 538 | static const struct inet6_protocol destopt_protocol = { |
248b238d DL |
539 | .handler = ipv6_destopt_rcv, |
540 | .flags = INET6_PROTO_NOPOLICY | INET6_PROTO_GSO_EXTHDR, | |
541 | }; | |
542 | ||
8ca896cf VY |
543 | static const struct net_offload dstopt_offload = { |
544 | .flags = INET6_PROTO_GSO_EXTHDR, | |
545 | }; | |
546 | ||
41135cc8 | 547 | static const struct inet6_protocol nodata_protocol = { |
248b238d DL |
548 | .handler = dst_discard, |
549 | .flags = INET6_PROTO_NOPOLICY, | |
550 | }; | |
551 | ||
552 | int __init ipv6_exthdrs_init(void) | |
1da177e4 | 553 | { |
248b238d DL |
554 | int ret; |
555 | ||
556 | ret = inet6_add_protocol(&rthdr_protocol, IPPROTO_ROUTING); | |
557 | if (ret) | |
558 | goto out; | |
559 | ||
560 | ret = inet6_add_protocol(&destopt_protocol, IPPROTO_DSTOPTS); | |
561 | if (ret) | |
562 | goto out_rthdr; | |
563 | ||
564 | ret = inet6_add_protocol(&nodata_protocol, IPPROTO_NONE); | |
565 | if (ret) | |
566 | goto out_destopt; | |
567 | ||
568 | out: | |
569 | return ret; | |
570 | out_rthdr: | |
571 | inet6_del_protocol(&rthdr_protocol, IPPROTO_ROUTING); | |
572 | out_destopt: | |
573 | inet6_del_protocol(&destopt_protocol, IPPROTO_DSTOPTS); | |
574 | goto out; | |
1da177e4 LT |
575 | }; |
576 | ||
248b238d DL |
577 | void ipv6_exthdrs_exit(void) |
578 | { | |
579 | inet6_del_protocol(&nodata_protocol, IPPROTO_NONE); | |
580 | inet6_del_protocol(&destopt_protocol, IPPROTO_DSTOPTS); | |
581 | inet6_del_protocol(&rthdr_protocol, IPPROTO_ROUTING); | |
582 | } | |
583 | ||
1da177e4 LT |
584 | /********************************** |
585 | Hop-by-hop options. | |
586 | **********************************/ | |
587 | ||
e76b2b25 | 588 | /* |
adf30907 | 589 | * Note: we cannot rely on skb_dst(skb) before we assign it in ip6_route_input(). |
e76b2b25 YH |
590 | */ |
591 | static inline struct inet6_dev *ipv6_skb_idev(struct sk_buff *skb) | |
592 | { | |
adf30907 | 593 | return skb_dst(skb) ? ip6_dst_idev(skb_dst(skb)) : __in6_dev_get(skb->dev); |
e76b2b25 YH |
594 | } |
595 | ||
2570a4f5 DM |
596 | static inline struct net *ipv6_skb_net(struct sk_buff *skb) |
597 | { | |
598 | return skb_dst(skb) ? dev_net(skb_dst(skb)->dev) : dev_net(skb->dev); | |
599 | } | |
600 | ||
1da177e4 LT |
601 | /* Router Alert as of RFC 2711 */ |
602 | ||
a50feda5 | 603 | static bool ipv6_hop_ra(struct sk_buff *skb, int optoff) |
1da177e4 | 604 | { |
d56f90a7 | 605 | const unsigned char *nh = skb_network_header(skb); |
a80ff03e | 606 | |
d56f90a7 | 607 | if (nh[optoff + 1] == 2) { |
1da177e4 | 608 | IP6CB(skb)->ra = optoff; |
a50feda5 | 609 | return true; |
1da177e4 | 610 | } |
64ce2073 | 611 | LIMIT_NETDEBUG(KERN_DEBUG "ipv6_hop_ra: wrong RA length %d\n", |
d56f90a7 | 612 | nh[optoff + 1]); |
1da177e4 | 613 | kfree_skb(skb); |
a50feda5 | 614 | return false; |
1da177e4 LT |
615 | } |
616 | ||
617 | /* Jumbo payload */ | |
618 | ||
a50feda5 | 619 | static bool ipv6_hop_jumbo(struct sk_buff *skb, int optoff) |
1da177e4 | 620 | { |
d56f90a7 | 621 | const unsigned char *nh = skb_network_header(skb); |
2570a4f5 | 622 | struct net *net = ipv6_skb_net(skb); |
1da177e4 LT |
623 | u32 pkt_len; |
624 | ||
d56f90a7 | 625 | if (nh[optoff + 1] != 4 || (optoff & 3) != 2) { |
64ce2073 | 626 | LIMIT_NETDEBUG(KERN_DEBUG "ipv6_hop_jumbo: wrong jumbo opt length/alignment %d\n", |
d56f90a7 | 627 | nh[optoff+1]); |
483a47d2 | 628 | IP6_INC_STATS_BH(net, ipv6_skb_idev(skb), |
a11d206d | 629 | IPSTATS_MIB_INHDRERRORS); |
1da177e4 LT |
630 | goto drop; |
631 | } | |
632 | ||
d56f90a7 | 633 | pkt_len = ntohl(*(__be32 *)(nh + optoff + 2)); |
1da177e4 | 634 | if (pkt_len <= IPV6_MAXPLEN) { |
483a47d2 DL |
635 | IP6_INC_STATS_BH(net, ipv6_skb_idev(skb), |
636 | IPSTATS_MIB_INHDRERRORS); | |
1da177e4 | 637 | icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, optoff+2); |
a50feda5 | 638 | return false; |
1da177e4 | 639 | } |
0660e03f | 640 | if (ipv6_hdr(skb)->payload_len) { |
483a47d2 DL |
641 | IP6_INC_STATS_BH(net, ipv6_skb_idev(skb), |
642 | IPSTATS_MIB_INHDRERRORS); | |
1da177e4 | 643 | icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, optoff); |
a50feda5 | 644 | return false; |
1da177e4 LT |
645 | } |
646 | ||
647 | if (pkt_len > skb->len - sizeof(struct ipv6hdr)) { | |
483a47d2 DL |
648 | IP6_INC_STATS_BH(net, ipv6_skb_idev(skb), |
649 | IPSTATS_MIB_INTRUNCATEDPKTS); | |
1da177e4 LT |
650 | goto drop; |
651 | } | |
42ca89c1 SH |
652 | |
653 | if (pskb_trim_rcsum(skb, pkt_len + sizeof(struct ipv6hdr))) | |
654 | goto drop; | |
655 | ||
a50feda5 | 656 | return true; |
1da177e4 LT |
657 | |
658 | drop: | |
659 | kfree_skb(skb); | |
a50feda5 | 660 | return false; |
1da177e4 LT |
661 | } |
662 | ||
a50feda5 | 663 | static const struct tlvtype_proc tlvprochopopt_lst[] = { |
1da177e4 LT |
664 | { |
665 | .type = IPV6_TLV_ROUTERALERT, | |
666 | .func = ipv6_hop_ra, | |
667 | }, | |
668 | { | |
669 | .type = IPV6_TLV_JUMBO, | |
670 | .func = ipv6_hop_jumbo, | |
671 | }, | |
672 | { -1, } | |
673 | }; | |
674 | ||
e5bbef20 | 675 | int ipv6_parse_hopopts(struct sk_buff *skb) |
1da177e4 | 676 | { |
951dbc8a PM |
677 | struct inet6_skb_parm *opt = IP6CB(skb); |
678 | ||
ec670095 | 679 | /* |
d56f90a7 | 680 | * skb_network_header(skb) is equal to skb->data, and |
cfe1fc77 | 681 | * skb_network_header_len(skb) is always equal to |
ec670095 YH |
682 | * sizeof(struct ipv6hdr) by definition of |
683 | * hop-by-hop options. | |
684 | */ | |
685 | if (!pskb_may_pull(skb, sizeof(struct ipv6hdr) + 8) || | |
9c70220b ACM |
686 | !pskb_may_pull(skb, (sizeof(struct ipv6hdr) + |
687 | ((skb_transport_header(skb)[1] + 1) << 3)))) { | |
ec670095 YH |
688 | kfree_skb(skb); |
689 | return -1; | |
690 | } | |
691 | ||
951dbc8a | 692 | opt->hop = sizeof(struct ipv6hdr); |
e5bbef20 | 693 | if (ip6_parse_tlv(tlvprochopopt_lst, skb)) { |
b0e380b1 | 694 | skb->transport_header += (skb_transport_header(skb)[1] + 1) << 3; |
dc435e6d | 695 | opt = IP6CB(skb); |
951dbc8a | 696 | opt->nhoff = sizeof(struct ipv6hdr); |
b809739a | 697 | return 1; |
951dbc8a | 698 | } |
1da177e4 LT |
699 | return -1; |
700 | } | |
701 | ||
702 | /* | |
703 | * Creating outbound headers. | |
704 | * | |
705 | * "build" functions work when skb is filled from head to tail (datagram) | |
706 | * "push" functions work when headers are added from tail to head (tcp) | |
707 | * | |
708 | * In both cases we assume, that caller reserved enough room | |
709 | * for headers. | |
710 | */ | |
711 | ||
712 | static void ipv6_push_rthdr(struct sk_buff *skb, u8 *proto, | |
713 | struct ipv6_rt_hdr *opt, | |
714 | struct in6_addr **addr_p) | |
715 | { | |
716 | struct rt0_hdr *phdr, *ihdr; | |
717 | int hops; | |
718 | ||
719 | ihdr = (struct rt0_hdr *) opt; | |
1ab1457c | 720 | |
1da177e4 LT |
721 | phdr = (struct rt0_hdr *) skb_push(skb, (ihdr->rt_hdr.hdrlen + 1) << 3); |
722 | memcpy(phdr, ihdr, sizeof(struct rt0_hdr)); | |
723 | ||
724 | hops = ihdr->rt_hdr.hdrlen >> 1; | |
725 | ||
726 | if (hops > 1) | |
727 | memcpy(phdr->addr, ihdr->addr + 1, | |
728 | (hops - 1) * sizeof(struct in6_addr)); | |
729 | ||
4e3fd7a0 | 730 | phdr->addr[hops - 1] = **addr_p; |
1da177e4 LT |
731 | *addr_p = ihdr->addr; |
732 | ||
733 | phdr->rt_hdr.nexthdr = *proto; | |
734 | *proto = NEXTHDR_ROUTING; | |
735 | } | |
736 | ||
737 | static void ipv6_push_exthdr(struct sk_buff *skb, u8 *proto, u8 type, struct ipv6_opt_hdr *opt) | |
738 | { | |
739 | struct ipv6_opt_hdr *h = (struct ipv6_opt_hdr *)skb_push(skb, ipv6_optlen(opt)); | |
740 | ||
741 | memcpy(h, opt, ipv6_optlen(opt)); | |
742 | h->nexthdr = *proto; | |
743 | *proto = type; | |
744 | } | |
745 | ||
746 | void ipv6_push_nfrag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt, | |
747 | u8 *proto, | |
748 | struct in6_addr **daddr) | |
749 | { | |
333fad53 | 750 | if (opt->srcrt) { |
1da177e4 | 751 | ipv6_push_rthdr(skb, proto, opt->srcrt, daddr); |
333fad53 YH |
752 | /* |
753 | * IPV6_RTHDRDSTOPTS is ignored | |
754 | * unless IPV6_RTHDR is set (RFC3542). | |
755 | */ | |
756 | if (opt->dst0opt) | |
757 | ipv6_push_exthdr(skb, proto, NEXTHDR_DEST, opt->dst0opt); | |
758 | } | |
1da177e4 LT |
759 | if (opt->hopopt) |
760 | ipv6_push_exthdr(skb, proto, NEXTHDR_HOP, opt->hopopt); | |
761 | } | |
7159039a YH |
762 | EXPORT_SYMBOL(ipv6_push_nfrag_opts); |
763 | ||
1da177e4 LT |
764 | void ipv6_push_frag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt, u8 *proto) |
765 | { | |
766 | if (opt->dst1opt) | |
767 | ipv6_push_exthdr(skb, proto, NEXTHDR_DEST, opt->dst1opt); | |
768 | } | |
769 | ||
770 | struct ipv6_txoptions * | |
771 | ipv6_dup_options(struct sock *sk, struct ipv6_txoptions *opt) | |
772 | { | |
773 | struct ipv6_txoptions *opt2; | |
774 | ||
775 | opt2 = sock_kmalloc(sk, opt->tot_len, GFP_ATOMIC); | |
776 | if (opt2) { | |
ac3c8172 | 777 | long dif = (char *)opt2 - (char *)opt; |
1da177e4 LT |
778 | memcpy(opt2, opt, opt->tot_len); |
779 | if (opt2->hopopt) | |
ac3c8172 | 780 | *((char **)&opt2->hopopt) += dif; |
1da177e4 | 781 | if (opt2->dst0opt) |
ac3c8172 | 782 | *((char **)&opt2->dst0opt) += dif; |
1da177e4 | 783 | if (opt2->dst1opt) |
ac3c8172 | 784 | *((char **)&opt2->dst1opt) += dif; |
1da177e4 | 785 | if (opt2->srcrt) |
ac3c8172 | 786 | *((char **)&opt2->srcrt) += dif; |
1da177e4 LT |
787 | } |
788 | return opt2; | |
789 | } | |
3cf3dc6c ACM |
790 | EXPORT_SYMBOL_GPL(ipv6_dup_options); |
791 | ||
333fad53 YH |
792 | static int ipv6_renew_option(void *ohdr, |
793 | struct ipv6_opt_hdr __user *newopt, int newoptlen, | |
794 | int inherit, | |
795 | struct ipv6_opt_hdr **hdr, | |
796 | char **p) | |
797 | { | |
798 | if (inherit) { | |
799 | if (ohdr) { | |
800 | memcpy(*p, ohdr, ipv6_optlen((struct ipv6_opt_hdr *)ohdr)); | |
801 | *hdr = (struct ipv6_opt_hdr *)*p; | |
e3192690 | 802 | *p += CMSG_ALIGN(ipv6_optlen(*hdr)); |
333fad53 YH |
803 | } |
804 | } else { | |
805 | if (newopt) { | |
806 | if (copy_from_user(*p, newopt, newoptlen)) | |
807 | return -EFAULT; | |
808 | *hdr = (struct ipv6_opt_hdr *)*p; | |
e3192690 | 809 | if (ipv6_optlen(*hdr) > newoptlen) |
333fad53 YH |
810 | return -EINVAL; |
811 | *p += CMSG_ALIGN(newoptlen); | |
812 | } | |
813 | } | |
814 | return 0; | |
815 | } | |
816 | ||
817 | struct ipv6_txoptions * | |
818 | ipv6_renew_options(struct sock *sk, struct ipv6_txoptions *opt, | |
819 | int newtype, | |
820 | struct ipv6_opt_hdr __user *newopt, int newoptlen) | |
821 | { | |
822 | int tot_len = 0; | |
823 | char *p; | |
824 | struct ipv6_txoptions *opt2; | |
825 | int err; | |
826 | ||
99c7bc01 YH |
827 | if (opt) { |
828 | if (newtype != IPV6_HOPOPTS && opt->hopopt) | |
829 | tot_len += CMSG_ALIGN(ipv6_optlen(opt->hopopt)); | |
830 | if (newtype != IPV6_RTHDRDSTOPTS && opt->dst0opt) | |
831 | tot_len += CMSG_ALIGN(ipv6_optlen(opt->dst0opt)); | |
832 | if (newtype != IPV6_RTHDR && opt->srcrt) | |
833 | tot_len += CMSG_ALIGN(ipv6_optlen(opt->srcrt)); | |
834 | if (newtype != IPV6_DSTOPTS && opt->dst1opt) | |
835 | tot_len += CMSG_ALIGN(ipv6_optlen(opt->dst1opt)); | |
836 | } | |
837 | ||
333fad53 YH |
838 | if (newopt && newoptlen) |
839 | tot_len += CMSG_ALIGN(newoptlen); | |
840 | ||
841 | if (!tot_len) | |
842 | return NULL; | |
843 | ||
8b8aa4b5 | 844 | tot_len += sizeof(*opt2); |
333fad53 YH |
845 | opt2 = sock_kmalloc(sk, tot_len, GFP_ATOMIC); |
846 | if (!opt2) | |
847 | return ERR_PTR(-ENOBUFS); | |
848 | ||
849 | memset(opt2, 0, tot_len); | |
850 | ||
851 | opt2->tot_len = tot_len; | |
852 | p = (char *)(opt2 + 1); | |
853 | ||
99c7bc01 | 854 | err = ipv6_renew_option(opt ? opt->hopopt : NULL, newopt, newoptlen, |
333fad53 YH |
855 | newtype != IPV6_HOPOPTS, |
856 | &opt2->hopopt, &p); | |
857 | if (err) | |
858 | goto out; | |
859 | ||
99c7bc01 | 860 | err = ipv6_renew_option(opt ? opt->dst0opt : NULL, newopt, newoptlen, |
333fad53 YH |
861 | newtype != IPV6_RTHDRDSTOPTS, |
862 | &opt2->dst0opt, &p); | |
863 | if (err) | |
864 | goto out; | |
865 | ||
99c7bc01 | 866 | err = ipv6_renew_option(opt ? opt->srcrt : NULL, newopt, newoptlen, |
333fad53 | 867 | newtype != IPV6_RTHDR, |
99c7bc01 | 868 | (struct ipv6_opt_hdr **)&opt2->srcrt, &p); |
333fad53 YH |
869 | if (err) |
870 | goto out; | |
871 | ||
99c7bc01 | 872 | err = ipv6_renew_option(opt ? opt->dst1opt : NULL, newopt, newoptlen, |
333fad53 YH |
873 | newtype != IPV6_DSTOPTS, |
874 | &opt2->dst1opt, &p); | |
875 | if (err) | |
876 | goto out; | |
877 | ||
878 | opt2->opt_nflen = (opt2->hopopt ? ipv6_optlen(opt2->hopopt) : 0) + | |
879 | (opt2->dst0opt ? ipv6_optlen(opt2->dst0opt) : 0) + | |
880 | (opt2->srcrt ? ipv6_optlen(opt2->srcrt) : 0); | |
881 | opt2->opt_flen = (opt2->dst1opt ? ipv6_optlen(opt2->dst1opt) : 0); | |
882 | ||
883 | return opt2; | |
884 | out: | |
8b8aa4b5 | 885 | sock_kfree_s(sk, opt2, opt2->tot_len); |
333fad53 YH |
886 | return ERR_PTR(err); |
887 | } | |
888 | ||
df9890c3 YH |
889 | struct ipv6_txoptions *ipv6_fixup_options(struct ipv6_txoptions *opt_space, |
890 | struct ipv6_txoptions *opt) | |
891 | { | |
892 | /* | |
893 | * ignore the dest before srcrt unless srcrt is being included. | |
894 | * --yoshfuji | |
895 | */ | |
896 | if (opt && opt->dst0opt && !opt->srcrt) { | |
897 | if (opt_space != opt) { | |
898 | memcpy(opt_space, opt, sizeof(*opt_space)); | |
899 | opt = opt_space; | |
900 | } | |
901 | opt->opt_nflen -= ipv6_optlen(opt->dst0opt); | |
902 | opt->dst0opt = NULL; | |
903 | } | |
904 | ||
905 | return opt; | |
906 | } | |
a495f836 | 907 | EXPORT_SYMBOL_GPL(ipv6_fixup_options); |
df9890c3 | 908 | |
20c59de2 AE |
909 | /** |
910 | * fl6_update_dst - update flowi destination address with info given | |
911 | * by srcrt option, if any. | |
912 | * | |
4c9483b2 | 913 | * @fl6: flowi6 for which daddr is to be updated |
20c59de2 | 914 | * @opt: struct ipv6_txoptions in which to look for srcrt opt |
4c9483b2 | 915 | * @orig: copy of original daddr address if modified |
20c59de2 AE |
916 | * |
917 | * Returns NULL if no txoptions or no srcrt, otherwise returns orig | |
4c9483b2 | 918 | * and initial value of fl6->daddr set in orig |
20c59de2 | 919 | */ |
4c9483b2 | 920 | struct in6_addr *fl6_update_dst(struct flowi6 *fl6, |
20c59de2 AE |
921 | const struct ipv6_txoptions *opt, |
922 | struct in6_addr *orig) | |
923 | { | |
924 | if (!opt || !opt->srcrt) | |
925 | return NULL; | |
926 | ||
4e3fd7a0 AD |
927 | *orig = fl6->daddr; |
928 | fl6->daddr = *((struct rt0_hdr *)opt->srcrt)->addr; | |
20c59de2 AE |
929 | return orig; |
930 | } | |
20c59de2 | 931 | EXPORT_SYMBOL_GPL(fl6_update_dst); |