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 LT |
49 | |
50 | #include <asm/uaccess.h> | |
2207afc8 | 51 | #include "ip6_offload.h" |
1da177e4 LT |
52 | |
53 | /* | |
54 | * Parsing tlv encoded headers. | |
55 | * | |
a50feda5 ED |
56 | * Parsing function "func" returns true, if parsing succeed |
57 | * and false, if it failed. | |
1da177e4 LT |
58 | * It MUST NOT touch skb->h. |
59 | */ | |
60 | ||
61 | struct tlvtype_proc { | |
62 | int type; | |
a50feda5 | 63 | bool (*func)(struct sk_buff *skb, int offset); |
1da177e4 LT |
64 | }; |
65 | ||
66 | /********************* | |
67 | Generic functions | |
68 | *********************/ | |
69 | ||
70 | /* An unknown option is detected, decide what to do */ | |
71 | ||
a50feda5 | 72 | static bool ip6_tlvopt_unknown(struct sk_buff *skb, int optoff) |
1da177e4 | 73 | { |
d56f90a7 | 74 | switch ((skb_network_header(skb)[optoff] & 0xC0) >> 6) { |
1da177e4 | 75 | case 0: /* ignore */ |
a50feda5 | 76 | return true; |
1da177e4 LT |
77 | |
78 | case 1: /* drop packet */ | |
79 | break; | |
80 | ||
81 | case 3: /* Send ICMP if not a multicast address and drop packet */ | |
82 | /* Actually, it is redundant check. icmp_send | |
83 | will recheck in any case. | |
84 | */ | |
0660e03f | 85 | if (ipv6_addr_is_multicast(&ipv6_hdr(skb)->daddr)) |
1da177e4 LT |
86 | break; |
87 | case 2: /* send ICMP PARM PROB regardless and drop packet */ | |
88 | icmpv6_param_prob(skb, ICMPV6_UNK_OPTION, optoff); | |
a50feda5 | 89 | return false; |
3ff50b79 | 90 | } |
1da177e4 LT |
91 | |
92 | kfree_skb(skb); | |
a50feda5 | 93 | return false; |
1da177e4 LT |
94 | } |
95 | ||
96 | /* Parse tlv encoded option header (hop-by-hop or destination) */ | |
97 | ||
a50feda5 | 98 | static bool ip6_parse_tlv(const struct tlvtype_proc *procs, struct sk_buff *skb) |
1da177e4 | 99 | { |
a50feda5 | 100 | const struct tlvtype_proc *curr; |
d56f90a7 | 101 | const unsigned char *nh = skb_network_header(skb); |
cfe1fc77 | 102 | int off = skb_network_header_len(skb); |
9c70220b | 103 | int len = (skb_transport_header(skb)[1] + 1) << 3; |
9b905fe6 | 104 | int padlen = 0; |
1da177e4 | 105 | |
ea2ae17d | 106 | if (skb_transport_offset(skb) + len > skb_headlen(skb)) |
1da177e4 LT |
107 | goto bad; |
108 | ||
109 | off += 2; | |
110 | len -= 2; | |
111 | ||
112 | while (len > 0) { | |
d56f90a7 | 113 | int optlen = nh[off + 1] + 2; |
c1412fce | 114 | int i; |
1da177e4 | 115 | |
d56f90a7 | 116 | switch (nh[off]) { |
1de5a71c | 117 | case IPV6_TLV_PAD1: |
1da177e4 | 118 | optlen = 1; |
9b905fe6 EZ |
119 | padlen++; |
120 | if (padlen > 7) | |
121 | goto bad; | |
1da177e4 LT |
122 | break; |
123 | ||
124 | case IPV6_TLV_PADN: | |
c1412fce EZ |
125 | /* RFC 2460 states that the purpose of PadN is |
126 | * to align the containing header to multiples | |
127 | * of 8. 7 is therefore the highest valid value. | |
128 | * See also RFC 4942, Section 2.1.9.5. | |
129 | */ | |
9b905fe6 EZ |
130 | padlen += optlen; |
131 | if (padlen > 7) | |
c1412fce EZ |
132 | goto bad; |
133 | /* RFC 4942 recommends receiving hosts to | |
134 | * actively check PadN payload to contain | |
135 | * only zeroes. | |
136 | */ | |
137 | for (i = 2; i < optlen; i++) { | |
138 | if (nh[off + i] != 0) | |
139 | goto bad; | |
140 | } | |
1da177e4 LT |
141 | break; |
142 | ||
143 | default: /* Other TLV code so scan list */ | |
144 | if (optlen > len) | |
145 | goto bad; | |
146 | for (curr=procs; curr->type >= 0; curr++) { | |
d56f90a7 | 147 | if (curr->type == nh[off]) { |
1ab1457c YH |
148 | /* type specific length/alignment |
149 | checks will be performed in the | |
1da177e4 | 150 | func(). */ |
a50feda5 ED |
151 | if (curr->func(skb, off) == false) |
152 | return false; | |
1da177e4 LT |
153 | break; |
154 | } | |
155 | } | |
156 | if (curr->type < 0) { | |
e5bbef20 | 157 | if (ip6_tlvopt_unknown(skb, off) == 0) |
a50feda5 | 158 | return false; |
1da177e4 | 159 | } |
9b905fe6 | 160 | padlen = 0; |
1da177e4 LT |
161 | break; |
162 | } | |
163 | off += optlen; | |
164 | len -= optlen; | |
165 | } | |
9b905fe6 EZ |
166 | /* This case will not be caught by above check since its padding |
167 | * length is smaller than 7: | |
168 | * 1 byte NH + 1 byte Length + 6 bytes Padding | |
169 | */ | |
170 | if ((padlen == 6) && ((off - skb_network_header_len(skb)) == 8)) | |
171 | goto bad; | |
172 | ||
1da177e4 | 173 | if (len == 0) |
a50feda5 | 174 | return true; |
1da177e4 LT |
175 | bad: |
176 | kfree_skb(skb); | |
a50feda5 | 177 | return false; |
1da177e4 LT |
178 | } |
179 | ||
180 | /***************************** | |
181 | Destination options header. | |
182 | *****************************/ | |
183 | ||
07a93626 | 184 | #if IS_ENABLED(CONFIG_IPV6_MIP6) |
a50feda5 | 185 | static bool ipv6_dest_hao(struct sk_buff *skb, int optoff) |
a831f5bb | 186 | { |
a831f5bb MN |
187 | struct ipv6_destopt_hao *hao; |
188 | struct inet6_skb_parm *opt = IP6CB(skb); | |
0660e03f | 189 | struct ipv6hdr *ipv6h = ipv6_hdr(skb); |
a831f5bb MN |
190 | struct in6_addr tmp_addr; |
191 | int ret; | |
192 | ||
193 | if (opt->dsthao) { | |
194 | LIMIT_NETDEBUG(KERN_DEBUG "hao duplicated\n"); | |
195 | goto discard; | |
196 | } | |
197 | opt->dsthao = opt->dst1; | |
198 | opt->dst1 = 0; | |
199 | ||
d56f90a7 | 200 | hao = (struct ipv6_destopt_hao *)(skb_network_header(skb) + optoff); |
a831f5bb MN |
201 | |
202 | if (hao->length != 16) { | |
203 | LIMIT_NETDEBUG( | |
204 | KERN_DEBUG "hao invalid option length = %d\n", hao->length); | |
205 | goto discard; | |
206 | } | |
207 | ||
208 | if (!(ipv6_addr_type(&hao->addr) & IPV6_ADDR_UNICAST)) { | |
209 | LIMIT_NETDEBUG( | |
5b095d98 | 210 | KERN_DEBUG "hao is not an unicast addr: %pI6\n", &hao->addr); |
a831f5bb MN |
211 | goto discard; |
212 | } | |
213 | ||
214 | ret = xfrm6_input_addr(skb, (xfrm_address_t *)&ipv6h->daddr, | |
215 | (xfrm_address_t *)&hao->addr, IPPROTO_DSTOPTS); | |
216 | if (unlikely(ret < 0)) | |
217 | goto discard; | |
218 | ||
219 | if (skb_cloned(skb)) { | |
65c88466 | 220 | if (pskb_expand_head(skb, 0, 0, GFP_ATOMIC)) |
a831f5bb MN |
221 | goto discard; |
222 | ||
a831f5bb | 223 | /* update all variable using below by copied skbuff */ |
65c88466 | 224 | hao = (struct ipv6_destopt_hao *)(skb_network_header(skb) + |
d56f90a7 | 225 | optoff); |
65c88466 | 226 | ipv6h = ipv6_hdr(skb); |
a831f5bb MN |
227 | } |
228 | ||
229 | if (skb->ip_summed == CHECKSUM_COMPLETE) | |
230 | skb->ip_summed = CHECKSUM_NONE; | |
231 | ||
4e3fd7a0 AD |
232 | tmp_addr = ipv6h->saddr; |
233 | ipv6h->saddr = hao->addr; | |
234 | hao->addr = tmp_addr; | |
a831f5bb | 235 | |
b7aa0bf7 | 236 | if (skb->tstamp.tv64 == 0) |
a831f5bb MN |
237 | __net_timestamp(skb); |
238 | ||
a50feda5 | 239 | return true; |
a831f5bb MN |
240 | |
241 | discard: | |
242 | kfree_skb(skb); | |
a50feda5 | 243 | return false; |
a831f5bb MN |
244 | } |
245 | #endif | |
246 | ||
a50feda5 | 247 | static const struct tlvtype_proc tlvprocdestopt_lst[] = { |
07a93626 | 248 | #if IS_ENABLED(CONFIG_IPV6_MIP6) |
a831f5bb MN |
249 | { |
250 | .type = IPV6_TLV_HAO, | |
251 | .func = ipv6_dest_hao, | |
252 | }, | |
253 | #endif | |
1da177e4 LT |
254 | {-1, NULL} |
255 | }; | |
256 | ||
e5bbef20 | 257 | static int ipv6_destopt_rcv(struct sk_buff *skb) |
1da177e4 | 258 | { |
1da177e4 | 259 | struct inet6_skb_parm *opt = IP6CB(skb); |
07a93626 | 260 | #if IS_ENABLED(CONFIG_IPV6_MIP6) |
a831f5bb MN |
261 | __u16 dstbuf; |
262 | #endif | |
897dc80b | 263 | struct dst_entry *dst = skb_dst(skb); |
1da177e4 | 264 | |
ea2ae17d ACM |
265 | if (!pskb_may_pull(skb, skb_transport_offset(skb) + 8) || |
266 | !pskb_may_pull(skb, (skb_transport_offset(skb) + | |
9c70220b | 267 | ((skb_transport_header(skb)[1] + 1) << 3)))) { |
897dc80b | 268 | IP6_INC_STATS_BH(dev_net(dst->dev), ip6_dst_idev(dst), |
a11d206d | 269 | IPSTATS_MIB_INHDRERRORS); |
1da177e4 LT |
270 | kfree_skb(skb); |
271 | return -1; | |
272 | } | |
273 | ||
cfe1fc77 | 274 | opt->lastopt = opt->dst1 = skb_network_header_len(skb); |
07a93626 | 275 | #if IS_ENABLED(CONFIG_IPV6_MIP6) |
a831f5bb MN |
276 | dstbuf = opt->dst1; |
277 | #endif | |
1da177e4 | 278 | |
e5bbef20 | 279 | if (ip6_parse_tlv(tlvprocdestopt_lst, skb)) { |
b0e380b1 | 280 | skb->transport_header += (skb_transport_header(skb)[1] + 1) << 3; |
dc435e6d | 281 | opt = IP6CB(skb); |
07a93626 | 282 | #if IS_ENABLED(CONFIG_IPV6_MIP6) |
a831f5bb MN |
283 | opt->nhoff = dstbuf; |
284 | #else | |
951dbc8a | 285 | opt->nhoff = opt->dst1; |
a831f5bb | 286 | #endif |
1da177e4 LT |
287 | return 1; |
288 | } | |
289 | ||
483a47d2 DL |
290 | IP6_INC_STATS_BH(dev_net(dst->dev), |
291 | ip6_dst_idev(dst), IPSTATS_MIB_INHDRERRORS); | |
1da177e4 LT |
292 | return -1; |
293 | } | |
294 | ||
1da177e4 LT |
295 | /******************************** |
296 | Routing header. | |
297 | ********************************/ | |
298 | ||
f6bc7d9e | 299 | /* called with rcu_read_lock() */ |
e5bbef20 | 300 | static int ipv6_rthdr_rcv(struct sk_buff *skb) |
1da177e4 | 301 | { |
1da177e4 | 302 | struct inet6_skb_parm *opt = IP6CB(skb); |
65d4ed92 | 303 | struct in6_addr *addr = NULL; |
1da177e4 | 304 | struct in6_addr daddr; |
0bcbc926 | 305 | struct inet6_dev *idev; |
1da177e4 | 306 | int n, i; |
1da177e4 LT |
307 | struct ipv6_rt_hdr *hdr; |
308 | struct rt0_hdr *rthdr; | |
483a47d2 DL |
309 | struct net *net = dev_net(skb->dev); |
310 | int accept_source_route = net->ipv6.devconf_all->accept_source_route; | |
0bcbc926 | 311 | |
f6bc7d9e ED |
312 | idev = __in6_dev_get(skb->dev); |
313 | if (idev && accept_source_route > idev->cnf.accept_source_route) | |
314 | accept_source_route = idev->cnf.accept_source_route; | |
0bcbc926 | 315 | |
ea2ae17d ACM |
316 | if (!pskb_may_pull(skb, skb_transport_offset(skb) + 8) || |
317 | !pskb_may_pull(skb, (skb_transport_offset(skb) + | |
9c70220b | 318 | ((skb_transport_header(skb)[1] + 1) << 3)))) { |
adf30907 | 319 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), |
a11d206d | 320 | IPSTATS_MIB_INHDRERRORS); |
1da177e4 LT |
321 | kfree_skb(skb); |
322 | return -1; | |
323 | } | |
324 | ||
9c70220b | 325 | hdr = (struct ipv6_rt_hdr *)skb_transport_header(skb); |
1da177e4 | 326 | |
0660e03f | 327 | if (ipv6_addr_is_multicast(&ipv6_hdr(skb)->daddr) || |
1da177e4 | 328 | skb->pkt_type != PACKET_HOST) { |
adf30907 | 329 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), |
a11d206d | 330 | IPSTATS_MIB_INADDRERRORS); |
1da177e4 LT |
331 | kfree_skb(skb); |
332 | return -1; | |
333 | } | |
334 | ||
335 | looped_back: | |
336 | if (hdr->segments_left == 0) { | |
65d4ed92 | 337 | switch (hdr->type) { |
07a93626 | 338 | #if IS_ENABLED(CONFIG_IPV6_MIP6) |
65d4ed92 MN |
339 | case IPV6_SRCRT_TYPE_2: |
340 | /* Silently discard type 2 header unless it was | |
341 | * processed by own | |
342 | */ | |
343 | if (!addr) { | |
adf30907 | 344 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), |
a11d206d | 345 | IPSTATS_MIB_INADDRERRORS); |
65d4ed92 MN |
346 | kfree_skb(skb); |
347 | return -1; | |
348 | } | |
349 | break; | |
350 | #endif | |
351 | default: | |
352 | break; | |
353 | } | |
354 | ||
cfe1fc77 | 355 | opt->lastopt = opt->srcrt = skb_network_header_len(skb); |
b0e380b1 | 356 | skb->transport_header += (hdr->hdrlen + 1) << 3; |
1da177e4 LT |
357 | opt->dst0 = opt->dst1; |
358 | opt->dst1 = 0; | |
d56f90a7 | 359 | opt->nhoff = (&hdr->nexthdr) - skb_network_header(skb); |
1da177e4 LT |
360 | return 1; |
361 | } | |
362 | ||
65d4ed92 | 363 | switch (hdr->type) { |
07a93626 | 364 | #if IS_ENABLED(CONFIG_IPV6_MIP6) |
65d4ed92 | 365 | case IPV6_SRCRT_TYPE_2: |
c382bb9d YH |
366 | if (accept_source_route < 0) |
367 | goto unknown_rh; | |
65d4ed92 MN |
368 | /* Silently discard invalid RTH type 2 */ |
369 | if (hdr->hdrlen != 2 || hdr->segments_left != 1) { | |
adf30907 | 370 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), |
a11d206d | 371 | IPSTATS_MIB_INHDRERRORS); |
65d4ed92 MN |
372 | kfree_skb(skb); |
373 | return -1; | |
374 | } | |
375 | break; | |
376 | #endif | |
c382bb9d YH |
377 | default: |
378 | goto unknown_rh; | |
1da177e4 | 379 | } |
1da177e4 LT |
380 | |
381 | /* | |
382 | * This is the routing header forwarding algorithm from | |
383 | * RFC 2460, page 16. | |
384 | */ | |
385 | ||
386 | n = hdr->hdrlen >> 1; | |
387 | ||
388 | if (hdr->segments_left > n) { | |
adf30907 | 389 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), |
a11d206d | 390 | IPSTATS_MIB_INHDRERRORS); |
d56f90a7 ACM |
391 | icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, |
392 | ((&hdr->segments_left) - | |
393 | skb_network_header(skb))); | |
1da177e4 LT |
394 | return -1; |
395 | } | |
396 | ||
397 | /* We are about to mangle packet header. Be careful! | |
398 | Do not damage packets queued somewhere. | |
399 | */ | |
400 | if (skb_cloned(skb)) { | |
1da177e4 | 401 | /* the copy is a forwarded packet */ |
65c88466 | 402 | if (pskb_expand_head(skb, 0, 0, GFP_ATOMIC)) { |
adf30907 | 403 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), |
a11d206d YH |
404 | IPSTATS_MIB_OUTDISCARDS); |
405 | kfree_skb(skb); | |
1da177e4 LT |
406 | return -1; |
407 | } | |
65c88466 | 408 | hdr = (struct ipv6_rt_hdr *)skb_transport_header(skb); |
1da177e4 LT |
409 | } |
410 | ||
84fa7933 | 411 | if (skb->ip_summed == CHECKSUM_COMPLETE) |
1da177e4 LT |
412 | skb->ip_summed = CHECKSUM_NONE; |
413 | ||
414 | i = n - --hdr->segments_left; | |
415 | ||
416 | rthdr = (struct rt0_hdr *) hdr; | |
417 | addr = rthdr->addr; | |
418 | addr += i - 1; | |
419 | ||
65d4ed92 | 420 | switch (hdr->type) { |
07a93626 | 421 | #if IS_ENABLED(CONFIG_IPV6_MIP6) |
65d4ed92 MN |
422 | case IPV6_SRCRT_TYPE_2: |
423 | if (xfrm6_input_addr(skb, (xfrm_address_t *)addr, | |
0660e03f | 424 | (xfrm_address_t *)&ipv6_hdr(skb)->saddr, |
65d4ed92 | 425 | IPPROTO_ROUTING) < 0) { |
adf30907 | 426 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), |
a11d206d | 427 | IPSTATS_MIB_INADDRERRORS); |
65d4ed92 MN |
428 | kfree_skb(skb); |
429 | return -1; | |
430 | } | |
adf30907 ED |
431 | if (!ipv6_chk_home_addr(dev_net(skb_dst(skb)->dev), addr)) { |
432 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), | |
a11d206d | 433 | IPSTATS_MIB_INADDRERRORS); |
65d4ed92 MN |
434 | kfree_skb(skb); |
435 | return -1; | |
436 | } | |
437 | break; | |
438 | #endif | |
439 | default: | |
440 | break; | |
441 | } | |
442 | ||
1da177e4 | 443 | if (ipv6_addr_is_multicast(addr)) { |
adf30907 | 444 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), |
a11d206d | 445 | IPSTATS_MIB_INADDRERRORS); |
1da177e4 LT |
446 | kfree_skb(skb); |
447 | return -1; | |
448 | } | |
449 | ||
4e3fd7a0 AD |
450 | daddr = *addr; |
451 | *addr = ipv6_hdr(skb)->daddr; | |
452 | ipv6_hdr(skb)->daddr = daddr; | |
1da177e4 | 453 | |
adf30907 | 454 | skb_dst_drop(skb); |
1da177e4 | 455 | ip6_route_input(skb); |
adf30907 | 456 | if (skb_dst(skb)->error) { |
d56f90a7 | 457 | skb_push(skb, skb->data - skb_network_header(skb)); |
1da177e4 LT |
458 | dst_input(skb); |
459 | return -1; | |
460 | } | |
461 | ||
adf30907 | 462 | if (skb_dst(skb)->dev->flags&IFF_LOOPBACK) { |
0660e03f | 463 | if (ipv6_hdr(skb)->hop_limit <= 1) { |
adf30907 | 464 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), |
a11d206d | 465 | IPSTATS_MIB_INHDRERRORS); |
1da177e4 | 466 | icmpv6_send(skb, ICMPV6_TIME_EXCEED, ICMPV6_EXC_HOPLIMIT, |
3ffe533c | 467 | 0); |
1da177e4 LT |
468 | kfree_skb(skb); |
469 | return -1; | |
470 | } | |
0660e03f | 471 | ipv6_hdr(skb)->hop_limit--; |
1da177e4 LT |
472 | goto looped_back; |
473 | } | |
474 | ||
d56f90a7 | 475 | skb_push(skb, skb->data - skb_network_header(skb)); |
1da177e4 LT |
476 | dst_input(skb); |
477 | return -1; | |
c382bb9d YH |
478 | |
479 | unknown_rh: | |
adf30907 | 480 | IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), IPSTATS_MIB_INHDRERRORS); |
c382bb9d YH |
481 | icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, |
482 | (&hdr->type) - skb_network_header(skb)); | |
483 | return -1; | |
1da177e4 LT |
484 | } |
485 | ||
41135cc8 | 486 | static const struct inet6_protocol rthdr_protocol = { |
1da177e4 | 487 | .handler = ipv6_rthdr_rcv, |
2207afc8 | 488 | .flags = INET6_PROTO_NOPOLICY, |
8ca896cf VY |
489 | }; |
490 | ||
41135cc8 | 491 | static const struct inet6_protocol destopt_protocol = { |
248b238d | 492 | .handler = ipv6_destopt_rcv, |
2207afc8 | 493 | .flags = INET6_PROTO_NOPOLICY, |
8ca896cf VY |
494 | }; |
495 | ||
41135cc8 | 496 | static const struct inet6_protocol nodata_protocol = { |
248b238d DL |
497 | .handler = dst_discard, |
498 | .flags = INET6_PROTO_NOPOLICY, | |
499 | }; | |
500 | ||
501 | int __init ipv6_exthdrs_init(void) | |
1da177e4 | 502 | { |
248b238d DL |
503 | int ret; |
504 | ||
3336288a | 505 | ret = ipv6_exthdrs_offload_init(); |
248b238d DL |
506 | if (ret) |
507 | goto out; | |
508 | ||
3336288a VY |
509 | ret = inet6_add_protocol(&rthdr_protocol, IPPROTO_ROUTING); |
510 | if (ret) | |
511 | goto out_offload; | |
512 | ||
248b238d DL |
513 | ret = inet6_add_protocol(&destopt_protocol, IPPROTO_DSTOPTS); |
514 | if (ret) | |
515 | goto out_rthdr; | |
516 | ||
517 | ret = inet6_add_protocol(&nodata_protocol, IPPROTO_NONE); | |
518 | if (ret) | |
519 | goto out_destopt; | |
520 | ||
521 | out: | |
522 | return ret; | |
248b238d DL |
523 | out_destopt: |
524 | inet6_del_protocol(&destopt_protocol, IPPROTO_DSTOPTS); | |
3336288a VY |
525 | out_rthdr: |
526 | inet6_del_protocol(&rthdr_protocol, IPPROTO_ROUTING); | |
527 | out_offload: | |
528 | ipv6_exthdrs_offload_exit(); | |
248b238d | 529 | goto out; |
1da177e4 LT |
530 | }; |
531 | ||
248b238d DL |
532 | void ipv6_exthdrs_exit(void) |
533 | { | |
2207afc8 | 534 | ipv6_exthdrs_offload_exit(); |
248b238d DL |
535 | inet6_del_protocol(&nodata_protocol, IPPROTO_NONE); |
536 | inet6_del_protocol(&destopt_protocol, IPPROTO_DSTOPTS); | |
537 | inet6_del_protocol(&rthdr_protocol, IPPROTO_ROUTING); | |
538 | } | |
539 | ||
1da177e4 LT |
540 | /********************************** |
541 | Hop-by-hop options. | |
542 | **********************************/ | |
543 | ||
e76b2b25 | 544 | /* |
adf30907 | 545 | * Note: we cannot rely on skb_dst(skb) before we assign it in ip6_route_input(). |
e76b2b25 YH |
546 | */ |
547 | static inline struct inet6_dev *ipv6_skb_idev(struct sk_buff *skb) | |
548 | { | |
adf30907 | 549 | return skb_dst(skb) ? ip6_dst_idev(skb_dst(skb)) : __in6_dev_get(skb->dev); |
e76b2b25 YH |
550 | } |
551 | ||
2570a4f5 DM |
552 | static inline struct net *ipv6_skb_net(struct sk_buff *skb) |
553 | { | |
554 | return skb_dst(skb) ? dev_net(skb_dst(skb)->dev) : dev_net(skb->dev); | |
555 | } | |
556 | ||
1da177e4 LT |
557 | /* Router Alert as of RFC 2711 */ |
558 | ||
a50feda5 | 559 | static bool ipv6_hop_ra(struct sk_buff *skb, int optoff) |
1da177e4 | 560 | { |
d56f90a7 | 561 | const unsigned char *nh = skb_network_header(skb); |
a80ff03e | 562 | |
d56f90a7 | 563 | if (nh[optoff + 1] == 2) { |
1da177e4 | 564 | IP6CB(skb)->ra = optoff; |
a50feda5 | 565 | return true; |
1da177e4 | 566 | } |
64ce2073 | 567 | LIMIT_NETDEBUG(KERN_DEBUG "ipv6_hop_ra: wrong RA length %d\n", |
d56f90a7 | 568 | nh[optoff + 1]); |
1da177e4 | 569 | kfree_skb(skb); |
a50feda5 | 570 | return false; |
1da177e4 LT |
571 | } |
572 | ||
573 | /* Jumbo payload */ | |
574 | ||
a50feda5 | 575 | static bool ipv6_hop_jumbo(struct sk_buff *skb, int optoff) |
1da177e4 | 576 | { |
d56f90a7 | 577 | const unsigned char *nh = skb_network_header(skb); |
2570a4f5 | 578 | struct net *net = ipv6_skb_net(skb); |
1da177e4 LT |
579 | u32 pkt_len; |
580 | ||
d56f90a7 | 581 | if (nh[optoff + 1] != 4 || (optoff & 3) != 2) { |
64ce2073 | 582 | LIMIT_NETDEBUG(KERN_DEBUG "ipv6_hop_jumbo: wrong jumbo opt length/alignment %d\n", |
d56f90a7 | 583 | nh[optoff+1]); |
483a47d2 | 584 | IP6_INC_STATS_BH(net, ipv6_skb_idev(skb), |
a11d206d | 585 | IPSTATS_MIB_INHDRERRORS); |
1da177e4 LT |
586 | goto drop; |
587 | } | |
588 | ||
d56f90a7 | 589 | pkt_len = ntohl(*(__be32 *)(nh + optoff + 2)); |
1da177e4 | 590 | if (pkt_len <= IPV6_MAXPLEN) { |
483a47d2 DL |
591 | IP6_INC_STATS_BH(net, ipv6_skb_idev(skb), |
592 | IPSTATS_MIB_INHDRERRORS); | |
1da177e4 | 593 | icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, optoff+2); |
a50feda5 | 594 | return false; |
1da177e4 | 595 | } |
0660e03f | 596 | if (ipv6_hdr(skb)->payload_len) { |
483a47d2 DL |
597 | IP6_INC_STATS_BH(net, ipv6_skb_idev(skb), |
598 | IPSTATS_MIB_INHDRERRORS); | |
1da177e4 | 599 | icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, optoff); |
a50feda5 | 600 | return false; |
1da177e4 LT |
601 | } |
602 | ||
603 | if (pkt_len > skb->len - sizeof(struct ipv6hdr)) { | |
483a47d2 DL |
604 | IP6_INC_STATS_BH(net, ipv6_skb_idev(skb), |
605 | IPSTATS_MIB_INTRUNCATEDPKTS); | |
1da177e4 LT |
606 | goto drop; |
607 | } | |
42ca89c1 SH |
608 | |
609 | if (pskb_trim_rcsum(skb, pkt_len + sizeof(struct ipv6hdr))) | |
610 | goto drop; | |
611 | ||
a50feda5 | 612 | return true; |
1da177e4 LT |
613 | |
614 | drop: | |
615 | kfree_skb(skb); | |
a50feda5 | 616 | return false; |
1da177e4 LT |
617 | } |
618 | ||
a50feda5 | 619 | static const struct tlvtype_proc tlvprochopopt_lst[] = { |
1da177e4 LT |
620 | { |
621 | .type = IPV6_TLV_ROUTERALERT, | |
622 | .func = ipv6_hop_ra, | |
623 | }, | |
624 | { | |
625 | .type = IPV6_TLV_JUMBO, | |
626 | .func = ipv6_hop_jumbo, | |
627 | }, | |
628 | { -1, } | |
629 | }; | |
630 | ||
e5bbef20 | 631 | int ipv6_parse_hopopts(struct sk_buff *skb) |
1da177e4 | 632 | { |
951dbc8a PM |
633 | struct inet6_skb_parm *opt = IP6CB(skb); |
634 | ||
ec670095 | 635 | /* |
d56f90a7 | 636 | * skb_network_header(skb) is equal to skb->data, and |
cfe1fc77 | 637 | * skb_network_header_len(skb) is always equal to |
ec670095 YH |
638 | * sizeof(struct ipv6hdr) by definition of |
639 | * hop-by-hop options. | |
640 | */ | |
641 | if (!pskb_may_pull(skb, sizeof(struct ipv6hdr) + 8) || | |
9c70220b ACM |
642 | !pskb_may_pull(skb, (sizeof(struct ipv6hdr) + |
643 | ((skb_transport_header(skb)[1] + 1) << 3)))) { | |
ec670095 YH |
644 | kfree_skb(skb); |
645 | return -1; | |
646 | } | |
647 | ||
951dbc8a | 648 | opt->hop = sizeof(struct ipv6hdr); |
e5bbef20 | 649 | if (ip6_parse_tlv(tlvprochopopt_lst, skb)) { |
b0e380b1 | 650 | skb->transport_header += (skb_transport_header(skb)[1] + 1) << 3; |
dc435e6d | 651 | opt = IP6CB(skb); |
951dbc8a | 652 | opt->nhoff = sizeof(struct ipv6hdr); |
b809739a | 653 | return 1; |
951dbc8a | 654 | } |
1da177e4 LT |
655 | return -1; |
656 | } | |
657 | ||
658 | /* | |
659 | * Creating outbound headers. | |
660 | * | |
661 | * "build" functions work when skb is filled from head to tail (datagram) | |
662 | * "push" functions work when headers are added from tail to head (tcp) | |
663 | * | |
664 | * In both cases we assume, that caller reserved enough room | |
665 | * for headers. | |
666 | */ | |
667 | ||
668 | static void ipv6_push_rthdr(struct sk_buff *skb, u8 *proto, | |
669 | struct ipv6_rt_hdr *opt, | |
670 | struct in6_addr **addr_p) | |
671 | { | |
672 | struct rt0_hdr *phdr, *ihdr; | |
673 | int hops; | |
674 | ||
675 | ihdr = (struct rt0_hdr *) opt; | |
1ab1457c | 676 | |
1da177e4 LT |
677 | phdr = (struct rt0_hdr *) skb_push(skb, (ihdr->rt_hdr.hdrlen + 1) << 3); |
678 | memcpy(phdr, ihdr, sizeof(struct rt0_hdr)); | |
679 | ||
680 | hops = ihdr->rt_hdr.hdrlen >> 1; | |
681 | ||
682 | if (hops > 1) | |
683 | memcpy(phdr->addr, ihdr->addr + 1, | |
684 | (hops - 1) * sizeof(struct in6_addr)); | |
685 | ||
4e3fd7a0 | 686 | phdr->addr[hops - 1] = **addr_p; |
1da177e4 LT |
687 | *addr_p = ihdr->addr; |
688 | ||
689 | phdr->rt_hdr.nexthdr = *proto; | |
690 | *proto = NEXTHDR_ROUTING; | |
691 | } | |
692 | ||
693 | static void ipv6_push_exthdr(struct sk_buff *skb, u8 *proto, u8 type, struct ipv6_opt_hdr *opt) | |
694 | { | |
695 | struct ipv6_opt_hdr *h = (struct ipv6_opt_hdr *)skb_push(skb, ipv6_optlen(opt)); | |
696 | ||
697 | memcpy(h, opt, ipv6_optlen(opt)); | |
698 | h->nexthdr = *proto; | |
699 | *proto = type; | |
700 | } | |
701 | ||
702 | void ipv6_push_nfrag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt, | |
703 | u8 *proto, | |
704 | struct in6_addr **daddr) | |
705 | { | |
333fad53 | 706 | if (opt->srcrt) { |
1da177e4 | 707 | ipv6_push_rthdr(skb, proto, opt->srcrt, daddr); |
333fad53 YH |
708 | /* |
709 | * IPV6_RTHDRDSTOPTS is ignored | |
710 | * unless IPV6_RTHDR is set (RFC3542). | |
711 | */ | |
712 | if (opt->dst0opt) | |
713 | ipv6_push_exthdr(skb, proto, NEXTHDR_DEST, opt->dst0opt); | |
714 | } | |
1da177e4 LT |
715 | if (opt->hopopt) |
716 | ipv6_push_exthdr(skb, proto, NEXTHDR_HOP, opt->hopopt); | |
717 | } | |
7159039a YH |
718 | EXPORT_SYMBOL(ipv6_push_nfrag_opts); |
719 | ||
1da177e4 LT |
720 | void ipv6_push_frag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt, u8 *proto) |
721 | { | |
722 | if (opt->dst1opt) | |
723 | ipv6_push_exthdr(skb, proto, NEXTHDR_DEST, opt->dst1opt); | |
724 | } | |
725 | ||
726 | struct ipv6_txoptions * | |
727 | ipv6_dup_options(struct sock *sk, struct ipv6_txoptions *opt) | |
728 | { | |
729 | struct ipv6_txoptions *opt2; | |
730 | ||
731 | opt2 = sock_kmalloc(sk, opt->tot_len, GFP_ATOMIC); | |
732 | if (opt2) { | |
ac3c8172 | 733 | long dif = (char *)opt2 - (char *)opt; |
1da177e4 LT |
734 | memcpy(opt2, opt, opt->tot_len); |
735 | if (opt2->hopopt) | |
ac3c8172 | 736 | *((char **)&opt2->hopopt) += dif; |
1da177e4 | 737 | if (opt2->dst0opt) |
ac3c8172 | 738 | *((char **)&opt2->dst0opt) += dif; |
1da177e4 | 739 | if (opt2->dst1opt) |
ac3c8172 | 740 | *((char **)&opt2->dst1opt) += dif; |
1da177e4 | 741 | if (opt2->srcrt) |
ac3c8172 | 742 | *((char **)&opt2->srcrt) += dif; |
1da177e4 LT |
743 | } |
744 | return opt2; | |
745 | } | |
3cf3dc6c ACM |
746 | EXPORT_SYMBOL_GPL(ipv6_dup_options); |
747 | ||
333fad53 YH |
748 | static int ipv6_renew_option(void *ohdr, |
749 | struct ipv6_opt_hdr __user *newopt, int newoptlen, | |
750 | int inherit, | |
751 | struct ipv6_opt_hdr **hdr, | |
752 | char **p) | |
753 | { | |
754 | if (inherit) { | |
755 | if (ohdr) { | |
756 | memcpy(*p, ohdr, ipv6_optlen((struct ipv6_opt_hdr *)ohdr)); | |
757 | *hdr = (struct ipv6_opt_hdr *)*p; | |
e3192690 | 758 | *p += CMSG_ALIGN(ipv6_optlen(*hdr)); |
333fad53 YH |
759 | } |
760 | } else { | |
761 | if (newopt) { | |
762 | if (copy_from_user(*p, newopt, newoptlen)) | |
763 | return -EFAULT; | |
764 | *hdr = (struct ipv6_opt_hdr *)*p; | |
e3192690 | 765 | if (ipv6_optlen(*hdr) > newoptlen) |
333fad53 YH |
766 | return -EINVAL; |
767 | *p += CMSG_ALIGN(newoptlen); | |
768 | } | |
769 | } | |
770 | return 0; | |
771 | } | |
772 | ||
773 | struct ipv6_txoptions * | |
774 | ipv6_renew_options(struct sock *sk, struct ipv6_txoptions *opt, | |
775 | int newtype, | |
776 | struct ipv6_opt_hdr __user *newopt, int newoptlen) | |
777 | { | |
778 | int tot_len = 0; | |
779 | char *p; | |
780 | struct ipv6_txoptions *opt2; | |
781 | int err; | |
782 | ||
99c7bc01 YH |
783 | if (opt) { |
784 | if (newtype != IPV6_HOPOPTS && opt->hopopt) | |
785 | tot_len += CMSG_ALIGN(ipv6_optlen(opt->hopopt)); | |
786 | if (newtype != IPV6_RTHDRDSTOPTS && opt->dst0opt) | |
787 | tot_len += CMSG_ALIGN(ipv6_optlen(opt->dst0opt)); | |
788 | if (newtype != IPV6_RTHDR && opt->srcrt) | |
789 | tot_len += CMSG_ALIGN(ipv6_optlen(opt->srcrt)); | |
790 | if (newtype != IPV6_DSTOPTS && opt->dst1opt) | |
791 | tot_len += CMSG_ALIGN(ipv6_optlen(opt->dst1opt)); | |
792 | } | |
793 | ||
333fad53 YH |
794 | if (newopt && newoptlen) |
795 | tot_len += CMSG_ALIGN(newoptlen); | |
796 | ||
797 | if (!tot_len) | |
798 | return NULL; | |
799 | ||
8b8aa4b5 | 800 | tot_len += sizeof(*opt2); |
333fad53 YH |
801 | opt2 = sock_kmalloc(sk, tot_len, GFP_ATOMIC); |
802 | if (!opt2) | |
803 | return ERR_PTR(-ENOBUFS); | |
804 | ||
805 | memset(opt2, 0, tot_len); | |
806 | ||
807 | opt2->tot_len = tot_len; | |
808 | p = (char *)(opt2 + 1); | |
809 | ||
99c7bc01 | 810 | err = ipv6_renew_option(opt ? opt->hopopt : NULL, newopt, newoptlen, |
333fad53 YH |
811 | newtype != IPV6_HOPOPTS, |
812 | &opt2->hopopt, &p); | |
813 | if (err) | |
814 | goto out; | |
815 | ||
99c7bc01 | 816 | err = ipv6_renew_option(opt ? opt->dst0opt : NULL, newopt, newoptlen, |
333fad53 YH |
817 | newtype != IPV6_RTHDRDSTOPTS, |
818 | &opt2->dst0opt, &p); | |
819 | if (err) | |
820 | goto out; | |
821 | ||
99c7bc01 | 822 | err = ipv6_renew_option(opt ? opt->srcrt : NULL, newopt, newoptlen, |
333fad53 | 823 | newtype != IPV6_RTHDR, |
99c7bc01 | 824 | (struct ipv6_opt_hdr **)&opt2->srcrt, &p); |
333fad53 YH |
825 | if (err) |
826 | goto out; | |
827 | ||
99c7bc01 | 828 | err = ipv6_renew_option(opt ? opt->dst1opt : NULL, newopt, newoptlen, |
333fad53 YH |
829 | newtype != IPV6_DSTOPTS, |
830 | &opt2->dst1opt, &p); | |
831 | if (err) | |
832 | goto out; | |
833 | ||
834 | opt2->opt_nflen = (opt2->hopopt ? ipv6_optlen(opt2->hopopt) : 0) + | |
835 | (opt2->dst0opt ? ipv6_optlen(opt2->dst0opt) : 0) + | |
836 | (opt2->srcrt ? ipv6_optlen(opt2->srcrt) : 0); | |
837 | opt2->opt_flen = (opt2->dst1opt ? ipv6_optlen(opt2->dst1opt) : 0); | |
838 | ||
839 | return opt2; | |
840 | out: | |
8b8aa4b5 | 841 | sock_kfree_s(sk, opt2, opt2->tot_len); |
333fad53 YH |
842 | return ERR_PTR(err); |
843 | } | |
844 | ||
df9890c3 YH |
845 | struct ipv6_txoptions *ipv6_fixup_options(struct ipv6_txoptions *opt_space, |
846 | struct ipv6_txoptions *opt) | |
847 | { | |
848 | /* | |
849 | * ignore the dest before srcrt unless srcrt is being included. | |
850 | * --yoshfuji | |
851 | */ | |
852 | if (opt && opt->dst0opt && !opt->srcrt) { | |
853 | if (opt_space != opt) { | |
854 | memcpy(opt_space, opt, sizeof(*opt_space)); | |
855 | opt = opt_space; | |
856 | } | |
857 | opt->opt_nflen -= ipv6_optlen(opt->dst0opt); | |
858 | opt->dst0opt = NULL; | |
859 | } | |
860 | ||
861 | return opt; | |
862 | } | |
a495f836 | 863 | EXPORT_SYMBOL_GPL(ipv6_fixup_options); |
df9890c3 | 864 | |
20c59de2 AE |
865 | /** |
866 | * fl6_update_dst - update flowi destination address with info given | |
867 | * by srcrt option, if any. | |
868 | * | |
4c9483b2 | 869 | * @fl6: flowi6 for which daddr is to be updated |
20c59de2 | 870 | * @opt: struct ipv6_txoptions in which to look for srcrt opt |
4c9483b2 | 871 | * @orig: copy of original daddr address if modified |
20c59de2 AE |
872 | * |
873 | * Returns NULL if no txoptions or no srcrt, otherwise returns orig | |
4c9483b2 | 874 | * and initial value of fl6->daddr set in orig |
20c59de2 | 875 | */ |
4c9483b2 | 876 | struct in6_addr *fl6_update_dst(struct flowi6 *fl6, |
20c59de2 AE |
877 | const struct ipv6_txoptions *opt, |
878 | struct in6_addr *orig) | |
879 | { | |
880 | if (!opt || !opt->srcrt) | |
881 | return NULL; | |
882 | ||
4e3fd7a0 AD |
883 | *orig = fl6->daddr; |
884 | fl6->daddr = *((struct rt0_hdr *)opt->srcrt)->addr; | |
20c59de2 AE |
885 | return orig; |
886 | } | |
20c59de2 | 887 | EXPORT_SYMBOL_GPL(fl6_update_dst); |