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> | |
07a93626 | 46 | #if IS_ENABLED(CONFIG_IPV6_MIP6) |
65d4ed92 MN |
47 | #include <net/xfrm.h> |
48 | #endif | |
1da177e4 | 49 | |
ce256981 | 50 | #include <linux/uaccess.h> |
1da177e4 LT |
51 | |
52 | /* | |
53 | * Parsing tlv encoded headers. | |
54 | * | |
a50feda5 ED |
55 | * Parsing function "func" returns true, if parsing succeed |
56 | * and false, if it failed. | |
1da177e4 LT |
57 | * It MUST NOT touch skb->h. |
58 | */ | |
59 | ||
60 | struct tlvtype_proc { | |
61 | int type; | |
a50feda5 | 62 | bool (*func)(struct sk_buff *skb, int offset); |
1da177e4 LT |
63 | }; |
64 | ||
65 | /********************* | |
66 | Generic functions | |
67 | *********************/ | |
68 | ||
69 | /* An unknown option is detected, decide what to do */ | |
70 | ||
a50feda5 | 71 | static bool ip6_tlvopt_unknown(struct sk_buff *skb, int optoff) |
1da177e4 | 72 | { |
d56f90a7 | 73 | switch ((skb_network_header(skb)[optoff] & 0xC0) >> 6) { |
1da177e4 | 74 | case 0: /* ignore */ |
a50feda5 | 75 | return true; |
1da177e4 LT |
76 | |
77 | case 1: /* drop packet */ | |
78 | break; | |
79 | ||
80 | case 3: /* Send ICMP if not a multicast address and drop packet */ | |
81 | /* Actually, it is redundant check. icmp_send | |
82 | will recheck in any case. | |
83 | */ | |
0660e03f | 84 | if (ipv6_addr_is_multicast(&ipv6_hdr(skb)->daddr)) |
1da177e4 LT |
85 | break; |
86 | case 2: /* send ICMP PARM PROB regardless and drop packet */ | |
87 | icmpv6_param_prob(skb, ICMPV6_UNK_OPTION, optoff); | |
a50feda5 | 88 | return false; |
3ff50b79 | 89 | } |
1da177e4 LT |
90 | |
91 | kfree_skb(skb); | |
a50feda5 | 92 | return false; |
1da177e4 LT |
93 | } |
94 | ||
95 | /* Parse tlv encoded option header (hop-by-hop or destination) */ | |
96 | ||
a50feda5 | 97 | static bool ip6_parse_tlv(const struct tlvtype_proc *procs, struct sk_buff *skb) |
1da177e4 | 98 | { |
a50feda5 | 99 | const struct tlvtype_proc *curr; |
d56f90a7 | 100 | const unsigned char *nh = skb_network_header(skb); |
cfe1fc77 | 101 | int off = skb_network_header_len(skb); |
9c70220b | 102 | int len = (skb_transport_header(skb)[1] + 1) << 3; |
9b905fe6 | 103 | int padlen = 0; |
1da177e4 | 104 | |
ea2ae17d | 105 | if (skb_transport_offset(skb) + len > skb_headlen(skb)) |
1da177e4 LT |
106 | goto bad; |
107 | ||
108 | off += 2; | |
109 | len -= 2; | |
110 | ||
111 | while (len > 0) { | |
d56f90a7 | 112 | int optlen = nh[off + 1] + 2; |
c1412fce | 113 | int i; |
1da177e4 | 114 | |
d56f90a7 | 115 | switch (nh[off]) { |
1de5a71c | 116 | case IPV6_TLV_PAD1: |
1da177e4 | 117 | optlen = 1; |
9b905fe6 EZ |
118 | padlen++; |
119 | if (padlen > 7) | |
120 | goto bad; | |
1da177e4 LT |
121 | break; |
122 | ||
123 | case IPV6_TLV_PADN: | |
c1412fce EZ |
124 | /* RFC 2460 states that the purpose of PadN is |
125 | * to align the containing header to multiples | |
126 | * of 8. 7 is therefore the highest valid value. | |
127 | * See also RFC 4942, Section 2.1.9.5. | |
128 | */ | |
9b905fe6 EZ |
129 | padlen += optlen; |
130 | if (padlen > 7) | |
c1412fce EZ |
131 | goto bad; |
132 | /* RFC 4942 recommends receiving hosts to | |
133 | * actively check PadN payload to contain | |
134 | * only zeroes. | |
135 | */ | |
136 | for (i = 2; i < optlen; i++) { | |
137 | if (nh[off + i] != 0) | |
138 | goto bad; | |
139 | } | |
1da177e4 LT |
140 | break; |
141 | ||
142 | default: /* Other TLV code so scan list */ | |
143 | if (optlen > len) | |
144 | goto bad; | |
67ba4152 | 145 | for (curr = procs; curr->type >= 0; curr++) { |
d56f90a7 | 146 | if (curr->type == nh[off]) { |
1ab1457c YH |
147 | /* type specific length/alignment |
148 | checks will be performed in the | |
1da177e4 | 149 | func(). */ |
a50feda5 ED |
150 | if (curr->func(skb, off) == false) |
151 | return false; | |
1da177e4 LT |
152 | break; |
153 | } | |
154 | } | |
155 | if (curr->type < 0) { | |
e5bbef20 | 156 | if (ip6_tlvopt_unknown(skb, off) == 0) |
a50feda5 | 157 | return false; |
1da177e4 | 158 | } |
9b905fe6 | 159 | padlen = 0; |
1da177e4 LT |
160 | break; |
161 | } | |
162 | off += optlen; | |
163 | len -= optlen; | |
164 | } | |
9b905fe6 | 165 | |
1da177e4 | 166 | if (len == 0) |
a50feda5 | 167 | return true; |
1da177e4 LT |
168 | bad: |
169 | kfree_skb(skb); | |
a50feda5 | 170 | return false; |
1da177e4 LT |
171 | } |
172 | ||
173 | /***************************** | |
174 | Destination options header. | |
175 | *****************************/ | |
176 | ||
07a93626 | 177 | #if IS_ENABLED(CONFIG_IPV6_MIP6) |
a50feda5 | 178 | static bool ipv6_dest_hao(struct sk_buff *skb, int optoff) |
a831f5bb | 179 | { |
a831f5bb MN |
180 | struct ipv6_destopt_hao *hao; |
181 | struct inet6_skb_parm *opt = IP6CB(skb); | |
0660e03f | 182 | struct ipv6hdr *ipv6h = ipv6_hdr(skb); |
a831f5bb MN |
183 | struct in6_addr tmp_addr; |
184 | int ret; | |
185 | ||
186 | if (opt->dsthao) { | |
ba7a46f1 | 187 | net_dbg_ratelimited("hao duplicated\n"); |
a831f5bb MN |
188 | goto discard; |
189 | } | |
190 | opt->dsthao = opt->dst1; | |
191 | opt->dst1 = 0; | |
192 | ||
d56f90a7 | 193 | hao = (struct ipv6_destopt_hao *)(skb_network_header(skb) + optoff); |
a831f5bb MN |
194 | |
195 | if (hao->length != 16) { | |
ba7a46f1 JP |
196 | net_dbg_ratelimited("hao invalid option length = %d\n", |
197 | hao->length); | |
a831f5bb MN |
198 | goto discard; |
199 | } | |
200 | ||
201 | if (!(ipv6_addr_type(&hao->addr) & IPV6_ADDR_UNICAST)) { | |
ba7a46f1 JP |
202 | net_dbg_ratelimited("hao is not an unicast addr: %pI6\n", |
203 | &hao->addr); | |
a831f5bb MN |
204 | goto discard; |
205 | } | |
206 | ||
207 | ret = xfrm6_input_addr(skb, (xfrm_address_t *)&ipv6h->daddr, | |
208 | (xfrm_address_t *)&hao->addr, IPPROTO_DSTOPTS); | |
209 | if (unlikely(ret < 0)) | |
210 | goto discard; | |
211 | ||
212 | if (skb_cloned(skb)) { | |
65c88466 | 213 | if (pskb_expand_head(skb, 0, 0, GFP_ATOMIC)) |
a831f5bb MN |
214 | goto discard; |
215 | ||
a831f5bb | 216 | /* update all variable using below by copied skbuff */ |
65c88466 | 217 | hao = (struct ipv6_destopt_hao *)(skb_network_header(skb) + |
d56f90a7 | 218 | optoff); |
65c88466 | 219 | ipv6h = ipv6_hdr(skb); |
a831f5bb MN |
220 | } |
221 | ||
222 | if (skb->ip_summed == CHECKSUM_COMPLETE) | |
223 | skb->ip_summed = CHECKSUM_NONE; | |
224 | ||
4e3fd7a0 AD |
225 | tmp_addr = ipv6h->saddr; |
226 | ipv6h->saddr = hao->addr; | |
227 | hao->addr = tmp_addr; | |
a831f5bb | 228 | |
b7aa0bf7 | 229 | if (skb->tstamp.tv64 == 0) |
a831f5bb MN |
230 | __net_timestamp(skb); |
231 | ||
a50feda5 | 232 | return true; |
a831f5bb MN |
233 | |
234 | discard: | |
235 | kfree_skb(skb); | |
a50feda5 | 236 | return false; |
a831f5bb MN |
237 | } |
238 | #endif | |
239 | ||
a50feda5 | 240 | static const struct tlvtype_proc tlvprocdestopt_lst[] = { |
07a93626 | 241 | #if IS_ENABLED(CONFIG_IPV6_MIP6) |
a831f5bb MN |
242 | { |
243 | .type = IPV6_TLV_HAO, | |
244 | .func = ipv6_dest_hao, | |
245 | }, | |
246 | #endif | |
1da177e4 LT |
247 | {-1, NULL} |
248 | }; | |
249 | ||
e5bbef20 | 250 | static int ipv6_destopt_rcv(struct sk_buff *skb) |
1da177e4 | 251 | { |
1da177e4 | 252 | struct inet6_skb_parm *opt = IP6CB(skb); |
07a93626 | 253 | #if IS_ENABLED(CONFIG_IPV6_MIP6) |
a831f5bb MN |
254 | __u16 dstbuf; |
255 | #endif | |
897dc80b | 256 | struct dst_entry *dst = skb_dst(skb); |
1da177e4 | 257 | |
ea2ae17d ACM |
258 | if (!pskb_may_pull(skb, skb_transport_offset(skb) + 8) || |
259 | !pskb_may_pull(skb, (skb_transport_offset(skb) + | |
9c70220b | 260 | ((skb_transport_header(skb)[1] + 1) << 3)))) { |
897dc80b | 261 | IP6_INC_STATS_BH(dev_net(dst->dev), ip6_dst_idev(dst), |
a11d206d | 262 | IPSTATS_MIB_INHDRERRORS); |
1da177e4 LT |
263 | kfree_skb(skb); |
264 | return -1; | |
265 | } | |
266 | ||
cfe1fc77 | 267 | opt->lastopt = opt->dst1 = skb_network_header_len(skb); |
07a93626 | 268 | #if IS_ENABLED(CONFIG_IPV6_MIP6) |
a831f5bb MN |
269 | dstbuf = opt->dst1; |
270 | #endif | |
1da177e4 | 271 | |
e5bbef20 | 272 | if (ip6_parse_tlv(tlvprocdestopt_lst, skb)) { |
b0e380b1 | 273 | skb->transport_header += (skb_transport_header(skb)[1] + 1) << 3; |
dc435e6d | 274 | opt = IP6CB(skb); |
07a93626 | 275 | #if IS_ENABLED(CONFIG_IPV6_MIP6) |
a831f5bb MN |
276 | opt->nhoff = dstbuf; |
277 | #else | |
951dbc8a | 278 | opt->nhoff = opt->dst1; |
a831f5bb | 279 | #endif |
1da177e4 LT |
280 | return 1; |
281 | } | |
282 | ||
483a47d2 DL |
283 | IP6_INC_STATS_BH(dev_net(dst->dev), |
284 | ip6_dst_idev(dst), IPSTATS_MIB_INHDRERRORS); | |
1da177e4 LT |
285 | return -1; |
286 | } | |
287 | ||
1da177e4 LT |
288 | /******************************** |
289 | Routing header. | |
290 | ********************************/ | |
291 | ||
f6bc7d9e | 292 | /* called with rcu_read_lock() */ |
e5bbef20 | 293 | static int ipv6_rthdr_rcv(struct sk_buff *skb) |
1da177e4 | 294 | { |
1da177e4 | 295 | struct inet6_skb_parm *opt = IP6CB(skb); |
65d4ed92 | 296 | struct in6_addr *addr = NULL; |
1da177e4 | 297 | struct in6_addr daddr; |
0bcbc926 | 298 | struct inet6_dev *idev; |
1da177e4 | 299 | int n, i; |
1da177e4 LT |
300 | struct ipv6_rt_hdr *hdr; |
301 | struct rt0_hdr *rthdr; | |
483a47d2 DL |
302 | struct net *net = dev_net(skb->dev); |
303 | int accept_source_route = net->ipv6.devconf_all->accept_source_route; | |
0bcbc926 | 304 | |
f6bc7d9e ED |
305 | idev = __in6_dev_get(skb->dev); |
306 | if (idev && accept_source_route > idev->cnf.accept_source_route) | |
307 | accept_source_route = idev->cnf.accept_source_route; | |
0bcbc926 | 308 | |
ea2ae17d ACM |
309 | if (!pskb_may_pull(skb, skb_transport_offset(skb) + 8) || |
310 | !pskb_may_pull(skb, (skb_transport_offset(skb) + | |
9c70220b | 311 | ((skb_transport_header(skb)[1] + 1) << 3)))) { |
adf30907 | 312 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), |
a11d206d | 313 | IPSTATS_MIB_INHDRERRORS); |
1da177e4 LT |
314 | kfree_skb(skb); |
315 | return -1; | |
316 | } | |
317 | ||
9c70220b | 318 | hdr = (struct ipv6_rt_hdr *)skb_transport_header(skb); |
1da177e4 | 319 | |
0660e03f | 320 | if (ipv6_addr_is_multicast(&ipv6_hdr(skb)->daddr) || |
1da177e4 | 321 | skb->pkt_type != PACKET_HOST) { |
adf30907 | 322 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), |
a11d206d | 323 | IPSTATS_MIB_INADDRERRORS); |
1da177e4 LT |
324 | kfree_skb(skb); |
325 | return -1; | |
326 | } | |
327 | ||
328 | looped_back: | |
329 | if (hdr->segments_left == 0) { | |
65d4ed92 | 330 | switch (hdr->type) { |
07a93626 | 331 | #if IS_ENABLED(CONFIG_IPV6_MIP6) |
65d4ed92 MN |
332 | case IPV6_SRCRT_TYPE_2: |
333 | /* Silently discard type 2 header unless it was | |
334 | * processed by own | |
335 | */ | |
336 | if (!addr) { | |
adf30907 | 337 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), |
a11d206d | 338 | IPSTATS_MIB_INADDRERRORS); |
65d4ed92 MN |
339 | kfree_skb(skb); |
340 | return -1; | |
341 | } | |
342 | break; | |
343 | #endif | |
344 | default: | |
345 | break; | |
346 | } | |
347 | ||
cfe1fc77 | 348 | opt->lastopt = opt->srcrt = skb_network_header_len(skb); |
b0e380b1 | 349 | skb->transport_header += (hdr->hdrlen + 1) << 3; |
1da177e4 LT |
350 | opt->dst0 = opt->dst1; |
351 | opt->dst1 = 0; | |
d56f90a7 | 352 | opt->nhoff = (&hdr->nexthdr) - skb_network_header(skb); |
1da177e4 LT |
353 | return 1; |
354 | } | |
355 | ||
65d4ed92 | 356 | switch (hdr->type) { |
07a93626 | 357 | #if IS_ENABLED(CONFIG_IPV6_MIP6) |
65d4ed92 | 358 | case IPV6_SRCRT_TYPE_2: |
c382bb9d YH |
359 | if (accept_source_route < 0) |
360 | goto unknown_rh; | |
65d4ed92 MN |
361 | /* Silently discard invalid RTH type 2 */ |
362 | if (hdr->hdrlen != 2 || hdr->segments_left != 1) { | |
adf30907 | 363 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), |
a11d206d | 364 | IPSTATS_MIB_INHDRERRORS); |
65d4ed92 MN |
365 | kfree_skb(skb); |
366 | return -1; | |
367 | } | |
368 | break; | |
369 | #endif | |
c382bb9d YH |
370 | default: |
371 | goto unknown_rh; | |
1da177e4 | 372 | } |
1da177e4 LT |
373 | |
374 | /* | |
375 | * This is the routing header forwarding algorithm from | |
376 | * RFC 2460, page 16. | |
377 | */ | |
378 | ||
379 | n = hdr->hdrlen >> 1; | |
380 | ||
381 | if (hdr->segments_left > n) { | |
adf30907 | 382 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), |
a11d206d | 383 | IPSTATS_MIB_INHDRERRORS); |
d56f90a7 ACM |
384 | icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, |
385 | ((&hdr->segments_left) - | |
386 | skb_network_header(skb))); | |
1da177e4 LT |
387 | return -1; |
388 | } | |
389 | ||
390 | /* We are about to mangle packet header. Be careful! | |
391 | Do not damage packets queued somewhere. | |
392 | */ | |
393 | if (skb_cloned(skb)) { | |
1da177e4 | 394 | /* the copy is a forwarded packet */ |
65c88466 | 395 | if (pskb_expand_head(skb, 0, 0, GFP_ATOMIC)) { |
adf30907 | 396 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), |
a11d206d YH |
397 | IPSTATS_MIB_OUTDISCARDS); |
398 | kfree_skb(skb); | |
1da177e4 LT |
399 | return -1; |
400 | } | |
65c88466 | 401 | hdr = (struct ipv6_rt_hdr *)skb_transport_header(skb); |
1da177e4 LT |
402 | } |
403 | ||
84fa7933 | 404 | if (skb->ip_summed == CHECKSUM_COMPLETE) |
1da177e4 LT |
405 | skb->ip_summed = CHECKSUM_NONE; |
406 | ||
407 | i = n - --hdr->segments_left; | |
408 | ||
409 | rthdr = (struct rt0_hdr *) hdr; | |
410 | addr = rthdr->addr; | |
411 | addr += i - 1; | |
412 | ||
65d4ed92 | 413 | switch (hdr->type) { |
07a93626 | 414 | #if IS_ENABLED(CONFIG_IPV6_MIP6) |
65d4ed92 MN |
415 | case IPV6_SRCRT_TYPE_2: |
416 | if (xfrm6_input_addr(skb, (xfrm_address_t *)addr, | |
0660e03f | 417 | (xfrm_address_t *)&ipv6_hdr(skb)->saddr, |
65d4ed92 | 418 | IPPROTO_ROUTING) < 0) { |
adf30907 | 419 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), |
a11d206d | 420 | IPSTATS_MIB_INADDRERRORS); |
65d4ed92 MN |
421 | kfree_skb(skb); |
422 | return -1; | |
423 | } | |
adf30907 ED |
424 | if (!ipv6_chk_home_addr(dev_net(skb_dst(skb)->dev), addr)) { |
425 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), | |
a11d206d | 426 | IPSTATS_MIB_INADDRERRORS); |
65d4ed92 MN |
427 | kfree_skb(skb); |
428 | return -1; | |
429 | } | |
430 | break; | |
431 | #endif | |
432 | default: | |
433 | break; | |
434 | } | |
435 | ||
1da177e4 | 436 | if (ipv6_addr_is_multicast(addr)) { |
adf30907 | 437 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), |
a11d206d | 438 | IPSTATS_MIB_INADDRERRORS); |
1da177e4 LT |
439 | kfree_skb(skb); |
440 | return -1; | |
441 | } | |
442 | ||
4e3fd7a0 AD |
443 | daddr = *addr; |
444 | *addr = ipv6_hdr(skb)->daddr; | |
445 | ipv6_hdr(skb)->daddr = daddr; | |
1da177e4 | 446 | |
adf30907 | 447 | skb_dst_drop(skb); |
1da177e4 | 448 | ip6_route_input(skb); |
adf30907 | 449 | if (skb_dst(skb)->error) { |
d56f90a7 | 450 | skb_push(skb, skb->data - skb_network_header(skb)); |
1da177e4 LT |
451 | dst_input(skb); |
452 | return -1; | |
453 | } | |
454 | ||
adf30907 | 455 | if (skb_dst(skb)->dev->flags&IFF_LOOPBACK) { |
0660e03f | 456 | if (ipv6_hdr(skb)->hop_limit <= 1) { |
adf30907 | 457 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), |
a11d206d | 458 | IPSTATS_MIB_INHDRERRORS); |
1da177e4 | 459 | icmpv6_send(skb, ICMPV6_TIME_EXCEED, ICMPV6_EXC_HOPLIMIT, |
3ffe533c | 460 | 0); |
1da177e4 LT |
461 | kfree_skb(skb); |
462 | return -1; | |
463 | } | |
0660e03f | 464 | ipv6_hdr(skb)->hop_limit--; |
1da177e4 LT |
465 | goto looped_back; |
466 | } | |
467 | ||
d56f90a7 | 468 | skb_push(skb, skb->data - skb_network_header(skb)); |
1da177e4 LT |
469 | dst_input(skb); |
470 | return -1; | |
c382bb9d YH |
471 | |
472 | unknown_rh: | |
adf30907 | 473 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), IPSTATS_MIB_INHDRERRORS); |
c382bb9d YH |
474 | icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, |
475 | (&hdr->type) - skb_network_header(skb)); | |
476 | return -1; | |
1da177e4 LT |
477 | } |
478 | ||
41135cc8 | 479 | static const struct inet6_protocol rthdr_protocol = { |
1da177e4 | 480 | .handler = ipv6_rthdr_rcv, |
2207afc8 | 481 | .flags = INET6_PROTO_NOPOLICY, |
8ca896cf VY |
482 | }; |
483 | ||
41135cc8 | 484 | static const struct inet6_protocol destopt_protocol = { |
248b238d | 485 | .handler = ipv6_destopt_rcv, |
2207afc8 | 486 | .flags = INET6_PROTO_NOPOLICY, |
8ca896cf VY |
487 | }; |
488 | ||
41135cc8 | 489 | static const struct inet6_protocol nodata_protocol = { |
248b238d DL |
490 | .handler = dst_discard, |
491 | .flags = INET6_PROTO_NOPOLICY, | |
492 | }; | |
493 | ||
494 | int __init ipv6_exthdrs_init(void) | |
1da177e4 | 495 | { |
248b238d DL |
496 | int ret; |
497 | ||
3336288a VY |
498 | ret = inet6_add_protocol(&rthdr_protocol, IPPROTO_ROUTING); |
499 | if (ret) | |
c6b641a4 | 500 | goto out; |
3336288a | 501 | |
248b238d DL |
502 | ret = inet6_add_protocol(&destopt_protocol, IPPROTO_DSTOPTS); |
503 | if (ret) | |
504 | goto out_rthdr; | |
505 | ||
506 | ret = inet6_add_protocol(&nodata_protocol, IPPROTO_NONE); | |
507 | if (ret) | |
508 | goto out_destopt; | |
509 | ||
510 | out: | |
511 | return ret; | |
248b238d DL |
512 | out_destopt: |
513 | inet6_del_protocol(&destopt_protocol, IPPROTO_DSTOPTS); | |
3336288a VY |
514 | out_rthdr: |
515 | inet6_del_protocol(&rthdr_protocol, IPPROTO_ROUTING); | |
248b238d | 516 | goto out; |
1da177e4 LT |
517 | }; |
518 | ||
248b238d DL |
519 | void ipv6_exthdrs_exit(void) |
520 | { | |
521 | inet6_del_protocol(&nodata_protocol, IPPROTO_NONE); | |
522 | inet6_del_protocol(&destopt_protocol, IPPROTO_DSTOPTS); | |
523 | inet6_del_protocol(&rthdr_protocol, IPPROTO_ROUTING); | |
524 | } | |
525 | ||
1da177e4 LT |
526 | /********************************** |
527 | Hop-by-hop options. | |
528 | **********************************/ | |
529 | ||
e76b2b25 | 530 | /* |
adf30907 | 531 | * Note: we cannot rely on skb_dst(skb) before we assign it in ip6_route_input(). |
e76b2b25 YH |
532 | */ |
533 | static inline struct inet6_dev *ipv6_skb_idev(struct sk_buff *skb) | |
534 | { | |
adf30907 | 535 | return skb_dst(skb) ? ip6_dst_idev(skb_dst(skb)) : __in6_dev_get(skb->dev); |
e76b2b25 YH |
536 | } |
537 | ||
2570a4f5 DM |
538 | static inline struct net *ipv6_skb_net(struct sk_buff *skb) |
539 | { | |
540 | return skb_dst(skb) ? dev_net(skb_dst(skb)->dev) : dev_net(skb->dev); | |
541 | } | |
542 | ||
1da177e4 LT |
543 | /* Router Alert as of RFC 2711 */ |
544 | ||
a50feda5 | 545 | static bool ipv6_hop_ra(struct sk_buff *skb, int optoff) |
1da177e4 | 546 | { |
d56f90a7 | 547 | const unsigned char *nh = skb_network_header(skb); |
a80ff03e | 548 | |
d56f90a7 | 549 | if (nh[optoff + 1] == 2) { |
dd3332bf YH |
550 | IP6CB(skb)->flags |= IP6SKB_ROUTERALERT; |
551 | memcpy(&IP6CB(skb)->ra, nh + optoff + 2, sizeof(IP6CB(skb)->ra)); | |
a50feda5 | 552 | return true; |
1da177e4 | 553 | } |
ba7a46f1 JP |
554 | net_dbg_ratelimited("ipv6_hop_ra: wrong RA length %d\n", |
555 | nh[optoff + 1]); | |
1da177e4 | 556 | kfree_skb(skb); |
a50feda5 | 557 | return false; |
1da177e4 LT |
558 | } |
559 | ||
560 | /* Jumbo payload */ | |
561 | ||
a50feda5 | 562 | static bool ipv6_hop_jumbo(struct sk_buff *skb, int optoff) |
1da177e4 | 563 | { |
d56f90a7 | 564 | const unsigned char *nh = skb_network_header(skb); |
2570a4f5 | 565 | struct net *net = ipv6_skb_net(skb); |
1da177e4 LT |
566 | u32 pkt_len; |
567 | ||
d56f90a7 | 568 | if (nh[optoff + 1] != 4 || (optoff & 3) != 2) { |
ba7a46f1 JP |
569 | net_dbg_ratelimited("ipv6_hop_jumbo: wrong jumbo opt length/alignment %d\n", |
570 | nh[optoff+1]); | |
483a47d2 | 571 | IP6_INC_STATS_BH(net, ipv6_skb_idev(skb), |
a11d206d | 572 | IPSTATS_MIB_INHDRERRORS); |
1da177e4 LT |
573 | goto drop; |
574 | } | |
575 | ||
d56f90a7 | 576 | pkt_len = ntohl(*(__be32 *)(nh + optoff + 2)); |
1da177e4 | 577 | if (pkt_len <= IPV6_MAXPLEN) { |
483a47d2 DL |
578 | IP6_INC_STATS_BH(net, ipv6_skb_idev(skb), |
579 | IPSTATS_MIB_INHDRERRORS); | |
1da177e4 | 580 | icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, optoff+2); |
a50feda5 | 581 | return false; |
1da177e4 | 582 | } |
0660e03f | 583 | if (ipv6_hdr(skb)->payload_len) { |
483a47d2 DL |
584 | IP6_INC_STATS_BH(net, ipv6_skb_idev(skb), |
585 | IPSTATS_MIB_INHDRERRORS); | |
1da177e4 | 586 | icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, optoff); |
a50feda5 | 587 | return false; |
1da177e4 LT |
588 | } |
589 | ||
590 | if (pkt_len > skb->len - sizeof(struct ipv6hdr)) { | |
483a47d2 DL |
591 | IP6_INC_STATS_BH(net, ipv6_skb_idev(skb), |
592 | IPSTATS_MIB_INTRUNCATEDPKTS); | |
1da177e4 LT |
593 | goto drop; |
594 | } | |
42ca89c1 SH |
595 | |
596 | if (pskb_trim_rcsum(skb, pkt_len + sizeof(struct ipv6hdr))) | |
597 | goto drop; | |
598 | ||
a50feda5 | 599 | return true; |
1da177e4 LT |
600 | |
601 | drop: | |
602 | kfree_skb(skb); | |
a50feda5 | 603 | return false; |
1da177e4 LT |
604 | } |
605 | ||
a50feda5 | 606 | static const struct tlvtype_proc tlvprochopopt_lst[] = { |
1da177e4 LT |
607 | { |
608 | .type = IPV6_TLV_ROUTERALERT, | |
609 | .func = ipv6_hop_ra, | |
610 | }, | |
611 | { | |
612 | .type = IPV6_TLV_JUMBO, | |
613 | .func = ipv6_hop_jumbo, | |
614 | }, | |
615 | { -1, } | |
616 | }; | |
617 | ||
e5bbef20 | 618 | int ipv6_parse_hopopts(struct sk_buff *skb) |
1da177e4 | 619 | { |
951dbc8a PM |
620 | struct inet6_skb_parm *opt = IP6CB(skb); |
621 | ||
ec670095 | 622 | /* |
d56f90a7 | 623 | * skb_network_header(skb) is equal to skb->data, and |
cfe1fc77 | 624 | * skb_network_header_len(skb) is always equal to |
ec670095 YH |
625 | * sizeof(struct ipv6hdr) by definition of |
626 | * hop-by-hop options. | |
627 | */ | |
628 | if (!pskb_may_pull(skb, sizeof(struct ipv6hdr) + 8) || | |
9c70220b ACM |
629 | !pskb_may_pull(skb, (sizeof(struct ipv6hdr) + |
630 | ((skb_transport_header(skb)[1] + 1) << 3)))) { | |
ec670095 YH |
631 | kfree_skb(skb); |
632 | return -1; | |
633 | } | |
634 | ||
8b58a398 | 635 | opt->flags |= IP6SKB_HOPBYHOP; |
e5bbef20 | 636 | if (ip6_parse_tlv(tlvprochopopt_lst, skb)) { |
b0e380b1 | 637 | skb->transport_header += (skb_transport_header(skb)[1] + 1) << 3; |
dc435e6d | 638 | opt = IP6CB(skb); |
951dbc8a | 639 | opt->nhoff = sizeof(struct ipv6hdr); |
b809739a | 640 | return 1; |
951dbc8a | 641 | } |
1da177e4 LT |
642 | return -1; |
643 | } | |
644 | ||
645 | /* | |
646 | * Creating outbound headers. | |
647 | * | |
648 | * "build" functions work when skb is filled from head to tail (datagram) | |
649 | * "push" functions work when headers are added from tail to head (tcp) | |
650 | * | |
651 | * In both cases we assume, that caller reserved enough room | |
652 | * for headers. | |
653 | */ | |
654 | ||
655 | static void ipv6_push_rthdr(struct sk_buff *skb, u8 *proto, | |
656 | struct ipv6_rt_hdr *opt, | |
657 | struct in6_addr **addr_p) | |
658 | { | |
659 | struct rt0_hdr *phdr, *ihdr; | |
660 | int hops; | |
661 | ||
662 | ihdr = (struct rt0_hdr *) opt; | |
1ab1457c | 663 | |
1da177e4 LT |
664 | phdr = (struct rt0_hdr *) skb_push(skb, (ihdr->rt_hdr.hdrlen + 1) << 3); |
665 | memcpy(phdr, ihdr, sizeof(struct rt0_hdr)); | |
666 | ||
667 | hops = ihdr->rt_hdr.hdrlen >> 1; | |
668 | ||
669 | if (hops > 1) | |
670 | memcpy(phdr->addr, ihdr->addr + 1, | |
671 | (hops - 1) * sizeof(struct in6_addr)); | |
672 | ||
4e3fd7a0 | 673 | phdr->addr[hops - 1] = **addr_p; |
1da177e4 LT |
674 | *addr_p = ihdr->addr; |
675 | ||
676 | phdr->rt_hdr.nexthdr = *proto; | |
677 | *proto = NEXTHDR_ROUTING; | |
678 | } | |
679 | ||
680 | static void ipv6_push_exthdr(struct sk_buff *skb, u8 *proto, u8 type, struct ipv6_opt_hdr *opt) | |
681 | { | |
682 | struct ipv6_opt_hdr *h = (struct ipv6_opt_hdr *)skb_push(skb, ipv6_optlen(opt)); | |
683 | ||
684 | memcpy(h, opt, ipv6_optlen(opt)); | |
685 | h->nexthdr = *proto; | |
686 | *proto = type; | |
687 | } | |
688 | ||
689 | void ipv6_push_nfrag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt, | |
690 | u8 *proto, | |
691 | struct in6_addr **daddr) | |
692 | { | |
333fad53 | 693 | if (opt->srcrt) { |
1da177e4 | 694 | ipv6_push_rthdr(skb, proto, opt->srcrt, daddr); |
333fad53 YH |
695 | /* |
696 | * IPV6_RTHDRDSTOPTS is ignored | |
697 | * unless IPV6_RTHDR is set (RFC3542). | |
698 | */ | |
699 | if (opt->dst0opt) | |
700 | ipv6_push_exthdr(skb, proto, NEXTHDR_DEST, opt->dst0opt); | |
701 | } | |
1da177e4 LT |
702 | if (opt->hopopt) |
703 | ipv6_push_exthdr(skb, proto, NEXTHDR_HOP, opt->hopopt); | |
704 | } | |
7159039a YH |
705 | EXPORT_SYMBOL(ipv6_push_nfrag_opts); |
706 | ||
1da177e4 LT |
707 | void ipv6_push_frag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt, u8 *proto) |
708 | { | |
709 | if (opt->dst1opt) | |
710 | ipv6_push_exthdr(skb, proto, NEXTHDR_DEST, opt->dst1opt); | |
711 | } | |
712 | ||
713 | struct ipv6_txoptions * | |
714 | ipv6_dup_options(struct sock *sk, struct ipv6_txoptions *opt) | |
715 | { | |
716 | struct ipv6_txoptions *opt2; | |
717 | ||
718 | opt2 = sock_kmalloc(sk, opt->tot_len, GFP_ATOMIC); | |
719 | if (opt2) { | |
ac3c8172 | 720 | long dif = (char *)opt2 - (char *)opt; |
1da177e4 LT |
721 | memcpy(opt2, opt, opt->tot_len); |
722 | if (opt2->hopopt) | |
ac3c8172 | 723 | *((char **)&opt2->hopopt) += dif; |
1da177e4 | 724 | if (opt2->dst0opt) |
ac3c8172 | 725 | *((char **)&opt2->dst0opt) += dif; |
1da177e4 | 726 | if (opt2->dst1opt) |
ac3c8172 | 727 | *((char **)&opt2->dst1opt) += dif; |
1da177e4 | 728 | if (opt2->srcrt) |
ac3c8172 | 729 | *((char **)&opt2->srcrt) += dif; |
45f6fad8 | 730 | atomic_set(&opt2->refcnt, 1); |
1da177e4 LT |
731 | } |
732 | return opt2; | |
733 | } | |
3cf3dc6c ACM |
734 | EXPORT_SYMBOL_GPL(ipv6_dup_options); |
735 | ||
333fad53 YH |
736 | static int ipv6_renew_option(void *ohdr, |
737 | struct ipv6_opt_hdr __user *newopt, int newoptlen, | |
738 | int inherit, | |
739 | struct ipv6_opt_hdr **hdr, | |
740 | char **p) | |
741 | { | |
742 | if (inherit) { | |
743 | if (ohdr) { | |
744 | memcpy(*p, ohdr, ipv6_optlen((struct ipv6_opt_hdr *)ohdr)); | |
745 | *hdr = (struct ipv6_opt_hdr *)*p; | |
e3192690 | 746 | *p += CMSG_ALIGN(ipv6_optlen(*hdr)); |
333fad53 YH |
747 | } |
748 | } else { | |
749 | if (newopt) { | |
750 | if (copy_from_user(*p, newopt, newoptlen)) | |
751 | return -EFAULT; | |
752 | *hdr = (struct ipv6_opt_hdr *)*p; | |
e3192690 | 753 | if (ipv6_optlen(*hdr) > newoptlen) |
333fad53 YH |
754 | return -EINVAL; |
755 | *p += CMSG_ALIGN(newoptlen); | |
756 | } | |
757 | } | |
758 | return 0; | |
759 | } | |
760 | ||
761 | struct ipv6_txoptions * | |
762 | ipv6_renew_options(struct sock *sk, struct ipv6_txoptions *opt, | |
763 | int newtype, | |
764 | struct ipv6_opt_hdr __user *newopt, int newoptlen) | |
765 | { | |
766 | int tot_len = 0; | |
767 | char *p; | |
768 | struct ipv6_txoptions *opt2; | |
769 | int err; | |
770 | ||
99c7bc01 YH |
771 | if (opt) { |
772 | if (newtype != IPV6_HOPOPTS && opt->hopopt) | |
773 | tot_len += CMSG_ALIGN(ipv6_optlen(opt->hopopt)); | |
774 | if (newtype != IPV6_RTHDRDSTOPTS && opt->dst0opt) | |
775 | tot_len += CMSG_ALIGN(ipv6_optlen(opt->dst0opt)); | |
776 | if (newtype != IPV6_RTHDR && opt->srcrt) | |
777 | tot_len += CMSG_ALIGN(ipv6_optlen(opt->srcrt)); | |
778 | if (newtype != IPV6_DSTOPTS && opt->dst1opt) | |
779 | tot_len += CMSG_ALIGN(ipv6_optlen(opt->dst1opt)); | |
780 | } | |
781 | ||
333fad53 YH |
782 | if (newopt && newoptlen) |
783 | tot_len += CMSG_ALIGN(newoptlen); | |
784 | ||
785 | if (!tot_len) | |
786 | return NULL; | |
787 | ||
8b8aa4b5 | 788 | tot_len += sizeof(*opt2); |
333fad53 YH |
789 | opt2 = sock_kmalloc(sk, tot_len, GFP_ATOMIC); |
790 | if (!opt2) | |
791 | return ERR_PTR(-ENOBUFS); | |
792 | ||
793 | memset(opt2, 0, tot_len); | |
45f6fad8 | 794 | atomic_set(&opt2->refcnt, 1); |
333fad53 YH |
795 | opt2->tot_len = tot_len; |
796 | p = (char *)(opt2 + 1); | |
797 | ||
99c7bc01 | 798 | err = ipv6_renew_option(opt ? opt->hopopt : NULL, newopt, newoptlen, |
333fad53 YH |
799 | newtype != IPV6_HOPOPTS, |
800 | &opt2->hopopt, &p); | |
801 | if (err) | |
802 | goto out; | |
803 | ||
99c7bc01 | 804 | err = ipv6_renew_option(opt ? opt->dst0opt : NULL, newopt, newoptlen, |
333fad53 YH |
805 | newtype != IPV6_RTHDRDSTOPTS, |
806 | &opt2->dst0opt, &p); | |
807 | if (err) | |
808 | goto out; | |
809 | ||
99c7bc01 | 810 | err = ipv6_renew_option(opt ? opt->srcrt : NULL, newopt, newoptlen, |
333fad53 | 811 | newtype != IPV6_RTHDR, |
99c7bc01 | 812 | (struct ipv6_opt_hdr **)&opt2->srcrt, &p); |
333fad53 YH |
813 | if (err) |
814 | goto out; | |
815 | ||
99c7bc01 | 816 | err = ipv6_renew_option(opt ? opt->dst1opt : NULL, newopt, newoptlen, |
333fad53 YH |
817 | newtype != IPV6_DSTOPTS, |
818 | &opt2->dst1opt, &p); | |
819 | if (err) | |
820 | goto out; | |
821 | ||
822 | opt2->opt_nflen = (opt2->hopopt ? ipv6_optlen(opt2->hopopt) : 0) + | |
823 | (opt2->dst0opt ? ipv6_optlen(opt2->dst0opt) : 0) + | |
824 | (opt2->srcrt ? ipv6_optlen(opt2->srcrt) : 0); | |
825 | opt2->opt_flen = (opt2->dst1opt ? ipv6_optlen(opt2->dst1opt) : 0); | |
826 | ||
827 | return opt2; | |
828 | out: | |
8b8aa4b5 | 829 | sock_kfree_s(sk, opt2, opt2->tot_len); |
333fad53 YH |
830 | return ERR_PTR(err); |
831 | } | |
832 | ||
df9890c3 YH |
833 | struct ipv6_txoptions *ipv6_fixup_options(struct ipv6_txoptions *opt_space, |
834 | struct ipv6_txoptions *opt) | |
835 | { | |
836 | /* | |
837 | * ignore the dest before srcrt unless srcrt is being included. | |
838 | * --yoshfuji | |
839 | */ | |
840 | if (opt && opt->dst0opt && !opt->srcrt) { | |
841 | if (opt_space != opt) { | |
842 | memcpy(opt_space, opt, sizeof(*opt_space)); | |
843 | opt = opt_space; | |
844 | } | |
845 | opt->opt_nflen -= ipv6_optlen(opt->dst0opt); | |
846 | opt->dst0opt = NULL; | |
847 | } | |
848 | ||
849 | return opt; | |
850 | } | |
a495f836 | 851 | EXPORT_SYMBOL_GPL(ipv6_fixup_options); |
df9890c3 | 852 | |
20c59de2 AE |
853 | /** |
854 | * fl6_update_dst - update flowi destination address with info given | |
855 | * by srcrt option, if any. | |
856 | * | |
4c9483b2 | 857 | * @fl6: flowi6 for which daddr is to be updated |
20c59de2 | 858 | * @opt: struct ipv6_txoptions in which to look for srcrt opt |
4c9483b2 | 859 | * @orig: copy of original daddr address if modified |
20c59de2 AE |
860 | * |
861 | * Returns NULL if no txoptions or no srcrt, otherwise returns orig | |
4c9483b2 | 862 | * and initial value of fl6->daddr set in orig |
20c59de2 | 863 | */ |
4c9483b2 | 864 | struct in6_addr *fl6_update_dst(struct flowi6 *fl6, |
20c59de2 AE |
865 | const struct ipv6_txoptions *opt, |
866 | struct in6_addr *orig) | |
867 | { | |
868 | if (!opt || !opt->srcrt) | |
869 | return NULL; | |
870 | ||
4e3fd7a0 AD |
871 | *orig = fl6->daddr; |
872 | fl6->daddr = *((struct rt0_hdr *)opt->srcrt)->addr; | |
20c59de2 AE |
873 | return orig; |
874 | } | |
20c59de2 | 875 | EXPORT_SYMBOL_GPL(fl6_update_dst); |