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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> | |
2e532b70 | 46 | #include <net/calipso.h> |
07a93626 | 47 | #if IS_ENABLED(CONFIG_IPV6_MIP6) |
65d4ed92 MN |
48 | #include <net/xfrm.h> |
49 | #endif | |
1ababeba DL |
50 | #include <linux/seg6.h> |
51 | #include <net/seg6.h> | |
9baee834 DL |
52 | #ifdef CONFIG_IPV6_SEG6_HMAC |
53 | #include <net/seg6_hmac.h> | |
54 | #endif | |
1da177e4 | 55 | |
ce256981 | 56 | #include <linux/uaccess.h> |
1da177e4 LT |
57 | |
58 | /* | |
59 | * Parsing tlv encoded headers. | |
60 | * | |
a50feda5 ED |
61 | * Parsing function "func" returns true, if parsing succeed |
62 | * and false, if it failed. | |
1da177e4 LT |
63 | * It MUST NOT touch skb->h. |
64 | */ | |
65 | ||
66 | struct tlvtype_proc { | |
67 | int type; | |
a50feda5 | 68 | bool (*func)(struct sk_buff *skb, int offset); |
1da177e4 LT |
69 | }; |
70 | ||
71 | /********************* | |
72 | Generic functions | |
73 | *********************/ | |
74 | ||
75 | /* An unknown option is detected, decide what to do */ | |
76 | ||
a50feda5 | 77 | static bool ip6_tlvopt_unknown(struct sk_buff *skb, int optoff) |
1da177e4 | 78 | { |
d56f90a7 | 79 | switch ((skb_network_header(skb)[optoff] & 0xC0) >> 6) { |
1da177e4 | 80 | case 0: /* ignore */ |
a50feda5 | 81 | return true; |
1da177e4 LT |
82 | |
83 | case 1: /* drop packet */ | |
84 | break; | |
85 | ||
86 | case 3: /* Send ICMP if not a multicast address and drop packet */ | |
87 | /* Actually, it is redundant check. icmp_send | |
88 | will recheck in any case. | |
89 | */ | |
0660e03f | 90 | if (ipv6_addr_is_multicast(&ipv6_hdr(skb)->daddr)) |
1da177e4 LT |
91 | break; |
92 | case 2: /* send ICMP PARM PROB regardless and drop packet */ | |
93 | icmpv6_param_prob(skb, ICMPV6_UNK_OPTION, optoff); | |
a50feda5 | 94 | return false; |
3ff50b79 | 95 | } |
1da177e4 LT |
96 | |
97 | kfree_skb(skb); | |
a50feda5 | 98 | return false; |
1da177e4 LT |
99 | } |
100 | ||
101 | /* Parse tlv encoded option header (hop-by-hop or destination) */ | |
102 | ||
a50feda5 | 103 | static bool ip6_parse_tlv(const struct tlvtype_proc *procs, struct sk_buff *skb) |
1da177e4 | 104 | { |
a50feda5 | 105 | const struct tlvtype_proc *curr; |
d56f90a7 | 106 | const unsigned char *nh = skb_network_header(skb); |
cfe1fc77 | 107 | int off = skb_network_header_len(skb); |
9c70220b | 108 | int len = (skb_transport_header(skb)[1] + 1) << 3; |
9b905fe6 | 109 | int padlen = 0; |
1da177e4 | 110 | |
ea2ae17d | 111 | if (skb_transport_offset(skb) + len > skb_headlen(skb)) |
1da177e4 LT |
112 | goto bad; |
113 | ||
114 | off += 2; | |
115 | len -= 2; | |
116 | ||
117 | while (len > 0) { | |
d56f90a7 | 118 | int optlen = nh[off + 1] + 2; |
c1412fce | 119 | int i; |
1da177e4 | 120 | |
d56f90a7 | 121 | switch (nh[off]) { |
1de5a71c | 122 | case IPV6_TLV_PAD1: |
1da177e4 | 123 | optlen = 1; |
9b905fe6 EZ |
124 | padlen++; |
125 | if (padlen > 7) | |
126 | goto bad; | |
1da177e4 LT |
127 | break; |
128 | ||
129 | case IPV6_TLV_PADN: | |
c1412fce EZ |
130 | /* RFC 2460 states that the purpose of PadN is |
131 | * to align the containing header to multiples | |
132 | * of 8. 7 is therefore the highest valid value. | |
133 | * See also RFC 4942, Section 2.1.9.5. | |
134 | */ | |
9b905fe6 EZ |
135 | padlen += optlen; |
136 | if (padlen > 7) | |
c1412fce EZ |
137 | goto bad; |
138 | /* RFC 4942 recommends receiving hosts to | |
139 | * actively check PadN payload to contain | |
140 | * only zeroes. | |
141 | */ | |
142 | for (i = 2; i < optlen; i++) { | |
143 | if (nh[off + i] != 0) | |
144 | goto bad; | |
145 | } | |
1da177e4 LT |
146 | break; |
147 | ||
148 | default: /* Other TLV code so scan list */ | |
149 | if (optlen > len) | |
150 | goto bad; | |
67ba4152 | 151 | for (curr = procs; curr->type >= 0; curr++) { |
d56f90a7 | 152 | if (curr->type == nh[off]) { |
1ab1457c YH |
153 | /* type specific length/alignment |
154 | checks will be performed in the | |
1da177e4 | 155 | func(). */ |
a50feda5 ED |
156 | if (curr->func(skb, off) == false) |
157 | return false; | |
1da177e4 LT |
158 | break; |
159 | } | |
160 | } | |
161 | if (curr->type < 0) { | |
e5bbef20 | 162 | if (ip6_tlvopt_unknown(skb, off) == 0) |
a50feda5 | 163 | return false; |
1da177e4 | 164 | } |
9b905fe6 | 165 | padlen = 0; |
1da177e4 LT |
166 | break; |
167 | } | |
168 | off += optlen; | |
169 | len -= optlen; | |
170 | } | |
9b905fe6 | 171 | |
1da177e4 | 172 | if (len == 0) |
a50feda5 | 173 | return true; |
1da177e4 LT |
174 | bad: |
175 | kfree_skb(skb); | |
a50feda5 | 176 | return false; |
1da177e4 LT |
177 | } |
178 | ||
179 | /***************************** | |
180 | Destination options header. | |
181 | *****************************/ | |
182 | ||
07a93626 | 183 | #if IS_ENABLED(CONFIG_IPV6_MIP6) |
a50feda5 | 184 | static bool ipv6_dest_hao(struct sk_buff *skb, int optoff) |
a831f5bb | 185 | { |
a831f5bb MN |
186 | struct ipv6_destopt_hao *hao; |
187 | struct inet6_skb_parm *opt = IP6CB(skb); | |
0660e03f | 188 | struct ipv6hdr *ipv6h = ipv6_hdr(skb); |
a831f5bb MN |
189 | struct in6_addr tmp_addr; |
190 | int ret; | |
191 | ||
192 | if (opt->dsthao) { | |
ba7a46f1 | 193 | net_dbg_ratelimited("hao duplicated\n"); |
a831f5bb MN |
194 | goto discard; |
195 | } | |
196 | opt->dsthao = opt->dst1; | |
197 | opt->dst1 = 0; | |
198 | ||
d56f90a7 | 199 | hao = (struct ipv6_destopt_hao *)(skb_network_header(skb) + optoff); |
a831f5bb MN |
200 | |
201 | if (hao->length != 16) { | |
ba7a46f1 JP |
202 | net_dbg_ratelimited("hao invalid option length = %d\n", |
203 | hao->length); | |
a831f5bb MN |
204 | goto discard; |
205 | } | |
206 | ||
207 | if (!(ipv6_addr_type(&hao->addr) & IPV6_ADDR_UNICAST)) { | |
ba7a46f1 JP |
208 | net_dbg_ratelimited("hao is not an unicast addr: %pI6\n", |
209 | &hao->addr); | |
a831f5bb MN |
210 | goto discard; |
211 | } | |
212 | ||
213 | ret = xfrm6_input_addr(skb, (xfrm_address_t *)&ipv6h->daddr, | |
214 | (xfrm_address_t *)&hao->addr, IPPROTO_DSTOPTS); | |
215 | if (unlikely(ret < 0)) | |
216 | goto discard; | |
217 | ||
218 | if (skb_cloned(skb)) { | |
65c88466 | 219 | if (pskb_expand_head(skb, 0, 0, GFP_ATOMIC)) |
a831f5bb MN |
220 | goto discard; |
221 | ||
a831f5bb | 222 | /* update all variable using below by copied skbuff */ |
65c88466 | 223 | hao = (struct ipv6_destopt_hao *)(skb_network_header(skb) + |
d56f90a7 | 224 | optoff); |
65c88466 | 225 | ipv6h = ipv6_hdr(skb); |
a831f5bb MN |
226 | } |
227 | ||
228 | if (skb->ip_summed == CHECKSUM_COMPLETE) | |
229 | skb->ip_summed = CHECKSUM_NONE; | |
230 | ||
4e3fd7a0 AD |
231 | tmp_addr = ipv6h->saddr; |
232 | ipv6h->saddr = hao->addr; | |
233 | hao->addr = tmp_addr; | |
a831f5bb | 234 | |
b7aa0bf7 | 235 | if (skb->tstamp.tv64 == 0) |
a831f5bb MN |
236 | __net_timestamp(skb); |
237 | ||
a50feda5 | 238 | return true; |
a831f5bb MN |
239 | |
240 | discard: | |
241 | kfree_skb(skb); | |
a50feda5 | 242 | return false; |
a831f5bb MN |
243 | } |
244 | #endif | |
245 | ||
a50feda5 | 246 | static const struct tlvtype_proc tlvprocdestopt_lst[] = { |
07a93626 | 247 | #if IS_ENABLED(CONFIG_IPV6_MIP6) |
a831f5bb MN |
248 | { |
249 | .type = IPV6_TLV_HAO, | |
250 | .func = ipv6_dest_hao, | |
251 | }, | |
252 | #endif | |
1da177e4 LT |
253 | {-1, NULL} |
254 | }; | |
255 | ||
e5bbef20 | 256 | static int ipv6_destopt_rcv(struct sk_buff *skb) |
1da177e4 | 257 | { |
1da177e4 | 258 | struct inet6_skb_parm *opt = IP6CB(skb); |
07a93626 | 259 | #if IS_ENABLED(CONFIG_IPV6_MIP6) |
a831f5bb MN |
260 | __u16 dstbuf; |
261 | #endif | |
897dc80b | 262 | struct dst_entry *dst = skb_dst(skb); |
1da177e4 | 263 | |
ea2ae17d ACM |
264 | if (!pskb_may_pull(skb, skb_transport_offset(skb) + 8) || |
265 | !pskb_may_pull(skb, (skb_transport_offset(skb) + | |
9c70220b | 266 | ((skb_transport_header(skb)[1] + 1) << 3)))) { |
1d015503 ED |
267 | __IP6_INC_STATS(dev_net(dst->dev), ip6_dst_idev(dst), |
268 | IPSTATS_MIB_INHDRERRORS); | |
1da177e4 LT |
269 | kfree_skb(skb); |
270 | return -1; | |
271 | } | |
272 | ||
cfe1fc77 | 273 | opt->lastopt = opt->dst1 = skb_network_header_len(skb); |
07a93626 | 274 | #if IS_ENABLED(CONFIG_IPV6_MIP6) |
a831f5bb MN |
275 | dstbuf = opt->dst1; |
276 | #endif | |
1da177e4 | 277 | |
e5bbef20 | 278 | if (ip6_parse_tlv(tlvprocdestopt_lst, skb)) { |
b0e380b1 | 279 | skb->transport_header += (skb_transport_header(skb)[1] + 1) << 3; |
dc435e6d | 280 | opt = IP6CB(skb); |
07a93626 | 281 | #if IS_ENABLED(CONFIG_IPV6_MIP6) |
a831f5bb MN |
282 | opt->nhoff = dstbuf; |
283 | #else | |
951dbc8a | 284 | opt->nhoff = opt->dst1; |
a831f5bb | 285 | #endif |
1da177e4 LT |
286 | return 1; |
287 | } | |
288 | ||
1d015503 ED |
289 | __IP6_INC_STATS(dev_net(dst->dev), |
290 | ip6_dst_idev(dst), IPSTATS_MIB_INHDRERRORS); | |
1da177e4 LT |
291 | return -1; |
292 | } | |
293 | ||
1ababeba DL |
294 | static void seg6_update_csum(struct sk_buff *skb) |
295 | { | |
296 | struct ipv6_sr_hdr *hdr; | |
297 | struct in6_addr *addr; | |
298 | __be32 from, to; | |
299 | ||
300 | /* srh is at transport offset and seg_left is already decremented | |
301 | * but daddr is not yet updated with next segment | |
302 | */ | |
303 | ||
304 | hdr = (struct ipv6_sr_hdr *)skb_transport_header(skb); | |
305 | addr = hdr->segments + hdr->segments_left; | |
306 | ||
307 | hdr->segments_left++; | |
308 | from = *(__be32 *)hdr; | |
309 | ||
310 | hdr->segments_left--; | |
311 | to = *(__be32 *)hdr; | |
312 | ||
313 | /* update skb csum with diff resulting from seg_left decrement */ | |
314 | ||
315 | update_csum_diff4(skb, from, to); | |
316 | ||
317 | /* compute csum diff between current and next segment and update */ | |
318 | ||
319 | update_csum_diff16(skb, (__be32 *)(&ipv6_hdr(skb)->daddr), | |
320 | (__be32 *)addr); | |
321 | } | |
322 | ||
323 | static int ipv6_srh_rcv(struct sk_buff *skb) | |
324 | { | |
325 | struct inet6_skb_parm *opt = IP6CB(skb); | |
326 | struct net *net = dev_net(skb->dev); | |
327 | struct ipv6_sr_hdr *hdr; | |
328 | struct inet6_dev *idev; | |
329 | struct in6_addr *addr; | |
330 | bool cleanup = false; | |
331 | int accept_seg6; | |
332 | ||
333 | hdr = (struct ipv6_sr_hdr *)skb_transport_header(skb); | |
334 | ||
335 | idev = __in6_dev_get(skb->dev); | |
336 | ||
337 | accept_seg6 = net->ipv6.devconf_all->seg6_enabled; | |
338 | if (accept_seg6 > idev->cnf.seg6_enabled) | |
339 | accept_seg6 = idev->cnf.seg6_enabled; | |
340 | ||
341 | if (!accept_seg6) { | |
342 | kfree_skb(skb); | |
343 | return -1; | |
344 | } | |
345 | ||
9baee834 DL |
346 | #ifdef CONFIG_IPV6_SEG6_HMAC |
347 | if (!seg6_hmac_validate_skb(skb)) { | |
348 | kfree_skb(skb); | |
349 | return -1; | |
350 | } | |
351 | #endif | |
352 | ||
1ababeba DL |
353 | looped_back: |
354 | if (hdr->segments_left > 0) { | |
355 | if (hdr->nexthdr != NEXTHDR_IPV6 && hdr->segments_left == 1 && | |
356 | sr_has_cleanup(hdr)) | |
357 | cleanup = true; | |
358 | } else { | |
359 | if (hdr->nexthdr == NEXTHDR_IPV6) { | |
360 | int offset = (hdr->hdrlen + 1) << 3; | |
361 | ||
362 | skb_postpull_rcsum(skb, skb_network_header(skb), | |
363 | skb_network_header_len(skb)); | |
364 | ||
365 | if (!pskb_pull(skb, offset)) { | |
366 | kfree_skb(skb); | |
367 | return -1; | |
368 | } | |
369 | skb_postpull_rcsum(skb, skb_transport_header(skb), | |
370 | offset); | |
371 | ||
372 | skb_reset_network_header(skb); | |
373 | skb_reset_transport_header(skb); | |
374 | skb->encapsulation = 0; | |
375 | ||
376 | __skb_tunnel_rx(skb, skb->dev, net); | |
377 | ||
378 | netif_rx(skb); | |
379 | return -1; | |
380 | } | |
381 | ||
382 | opt->srcrt = skb_network_header_len(skb); | |
383 | opt->lastopt = opt->srcrt; | |
384 | skb->transport_header += (hdr->hdrlen + 1) << 3; | |
385 | opt->nhoff = (&hdr->nexthdr) - skb_network_header(skb); | |
386 | ||
387 | return 1; | |
388 | } | |
389 | ||
390 | if (hdr->segments_left >= (hdr->hdrlen >> 1)) { | |
391 | __IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)), | |
392 | IPSTATS_MIB_INHDRERRORS); | |
393 | icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, | |
394 | ((&hdr->segments_left) - | |
395 | skb_network_header(skb))); | |
396 | kfree_skb(skb); | |
397 | return -1; | |
398 | } | |
399 | ||
400 | if (skb_cloned(skb)) { | |
401 | if (pskb_expand_head(skb, 0, 0, GFP_ATOMIC)) { | |
402 | __IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)), | |
403 | IPSTATS_MIB_OUTDISCARDS); | |
404 | kfree_skb(skb); | |
405 | return -1; | |
406 | } | |
407 | } | |
408 | ||
409 | hdr = (struct ipv6_sr_hdr *)skb_transport_header(skb); | |
410 | ||
411 | hdr->segments_left--; | |
412 | addr = hdr->segments + hdr->segments_left; | |
413 | ||
414 | skb_push(skb, sizeof(struct ipv6hdr)); | |
415 | ||
416 | if (skb->ip_summed == CHECKSUM_COMPLETE) | |
417 | seg6_update_csum(skb); | |
418 | ||
419 | ipv6_hdr(skb)->daddr = *addr; | |
420 | ||
421 | if (cleanup) { | |
422 | int srhlen = (hdr->hdrlen + 1) << 3; | |
423 | int nh = hdr->nexthdr; | |
424 | ||
425 | skb_pull_rcsum(skb, sizeof(struct ipv6hdr) + srhlen); | |
426 | memmove(skb_network_header(skb) + srhlen, | |
427 | skb_network_header(skb), | |
428 | (unsigned char *)hdr - skb_network_header(skb)); | |
429 | skb->network_header += srhlen; | |
430 | ipv6_hdr(skb)->nexthdr = nh; | |
431 | ipv6_hdr(skb)->payload_len = htons(skb->len - | |
432 | sizeof(struct ipv6hdr)); | |
433 | skb_push_rcsum(skb, sizeof(struct ipv6hdr)); | |
434 | } | |
435 | ||
436 | skb_dst_drop(skb); | |
437 | ||
438 | ip6_route_input(skb); | |
439 | ||
440 | if (skb_dst(skb)->error) { | |
441 | dst_input(skb); | |
442 | return -1; | |
443 | } | |
444 | ||
445 | if (skb_dst(skb)->dev->flags & IFF_LOOPBACK) { | |
446 | if (ipv6_hdr(skb)->hop_limit <= 1) { | |
447 | __IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)), | |
448 | IPSTATS_MIB_INHDRERRORS); | |
449 | icmpv6_send(skb, ICMPV6_TIME_EXCEED, | |
450 | ICMPV6_EXC_HOPLIMIT, 0); | |
451 | kfree_skb(skb); | |
452 | return -1; | |
453 | } | |
454 | ipv6_hdr(skb)->hop_limit--; | |
455 | ||
456 | /* be sure that srh is still present before reinjecting */ | |
457 | if (!cleanup) { | |
458 | skb_pull(skb, sizeof(struct ipv6hdr)); | |
459 | goto looped_back; | |
460 | } | |
461 | skb_set_transport_header(skb, sizeof(struct ipv6hdr)); | |
462 | IP6CB(skb)->nhoff = offsetof(struct ipv6hdr, nexthdr); | |
463 | } | |
464 | ||
465 | dst_input(skb); | |
466 | ||
467 | return -1; | |
468 | } | |
469 | ||
1da177e4 LT |
470 | /******************************** |
471 | Routing header. | |
472 | ********************************/ | |
473 | ||
f6bc7d9e | 474 | /* called with rcu_read_lock() */ |
e5bbef20 | 475 | static int ipv6_rthdr_rcv(struct sk_buff *skb) |
1da177e4 | 476 | { |
1da177e4 | 477 | struct inet6_skb_parm *opt = IP6CB(skb); |
65d4ed92 | 478 | struct in6_addr *addr = NULL; |
1da177e4 | 479 | struct in6_addr daddr; |
0bcbc926 | 480 | struct inet6_dev *idev; |
1da177e4 | 481 | int n, i; |
1da177e4 LT |
482 | struct ipv6_rt_hdr *hdr; |
483 | struct rt0_hdr *rthdr; | |
483a47d2 DL |
484 | struct net *net = dev_net(skb->dev); |
485 | int accept_source_route = net->ipv6.devconf_all->accept_source_route; | |
0bcbc926 | 486 | |
f6bc7d9e ED |
487 | idev = __in6_dev_get(skb->dev); |
488 | if (idev && accept_source_route > idev->cnf.accept_source_route) | |
489 | accept_source_route = idev->cnf.accept_source_route; | |
0bcbc926 | 490 | |
ea2ae17d ACM |
491 | if (!pskb_may_pull(skb, skb_transport_offset(skb) + 8) || |
492 | !pskb_may_pull(skb, (skb_transport_offset(skb) + | |
9c70220b | 493 | ((skb_transport_header(skb)[1] + 1) << 3)))) { |
1d015503 ED |
494 | __IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)), |
495 | IPSTATS_MIB_INHDRERRORS); | |
1da177e4 LT |
496 | kfree_skb(skb); |
497 | return -1; | |
498 | } | |
499 | ||
9c70220b | 500 | hdr = (struct ipv6_rt_hdr *)skb_transport_header(skb); |
1da177e4 | 501 | |
0660e03f | 502 | if (ipv6_addr_is_multicast(&ipv6_hdr(skb)->daddr) || |
1da177e4 | 503 | skb->pkt_type != PACKET_HOST) { |
1d015503 ED |
504 | __IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)), |
505 | IPSTATS_MIB_INADDRERRORS); | |
1da177e4 LT |
506 | kfree_skb(skb); |
507 | return -1; | |
508 | } | |
509 | ||
1ababeba DL |
510 | /* segment routing */ |
511 | if (hdr->type == IPV6_SRCRT_TYPE_4) | |
512 | return ipv6_srh_rcv(skb); | |
513 | ||
1da177e4 LT |
514 | looped_back: |
515 | if (hdr->segments_left == 0) { | |
65d4ed92 | 516 | switch (hdr->type) { |
07a93626 | 517 | #if IS_ENABLED(CONFIG_IPV6_MIP6) |
65d4ed92 MN |
518 | case IPV6_SRCRT_TYPE_2: |
519 | /* Silently discard type 2 header unless it was | |
520 | * processed by own | |
521 | */ | |
522 | if (!addr) { | |
1d015503 ED |
523 | __IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)), |
524 | IPSTATS_MIB_INADDRERRORS); | |
65d4ed92 MN |
525 | kfree_skb(skb); |
526 | return -1; | |
527 | } | |
528 | break; | |
529 | #endif | |
530 | default: | |
531 | break; | |
532 | } | |
533 | ||
cfe1fc77 | 534 | opt->lastopt = opt->srcrt = skb_network_header_len(skb); |
b0e380b1 | 535 | skb->transport_header += (hdr->hdrlen + 1) << 3; |
1da177e4 LT |
536 | opt->dst0 = opt->dst1; |
537 | opt->dst1 = 0; | |
d56f90a7 | 538 | opt->nhoff = (&hdr->nexthdr) - skb_network_header(skb); |
1da177e4 LT |
539 | return 1; |
540 | } | |
541 | ||
65d4ed92 | 542 | switch (hdr->type) { |
07a93626 | 543 | #if IS_ENABLED(CONFIG_IPV6_MIP6) |
65d4ed92 | 544 | case IPV6_SRCRT_TYPE_2: |
c382bb9d YH |
545 | if (accept_source_route < 0) |
546 | goto unknown_rh; | |
65d4ed92 MN |
547 | /* Silently discard invalid RTH type 2 */ |
548 | if (hdr->hdrlen != 2 || hdr->segments_left != 1) { | |
1d015503 ED |
549 | __IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)), |
550 | IPSTATS_MIB_INHDRERRORS); | |
65d4ed92 MN |
551 | kfree_skb(skb); |
552 | return -1; | |
553 | } | |
554 | break; | |
555 | #endif | |
c382bb9d YH |
556 | default: |
557 | goto unknown_rh; | |
1da177e4 | 558 | } |
1da177e4 LT |
559 | |
560 | /* | |
561 | * This is the routing header forwarding algorithm from | |
562 | * RFC 2460, page 16. | |
563 | */ | |
564 | ||
565 | n = hdr->hdrlen >> 1; | |
566 | ||
567 | if (hdr->segments_left > n) { | |
1d015503 ED |
568 | __IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)), |
569 | IPSTATS_MIB_INHDRERRORS); | |
d56f90a7 ACM |
570 | icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, |
571 | ((&hdr->segments_left) - | |
572 | skb_network_header(skb))); | |
1da177e4 LT |
573 | return -1; |
574 | } | |
575 | ||
576 | /* We are about to mangle packet header. Be careful! | |
577 | Do not damage packets queued somewhere. | |
578 | */ | |
579 | if (skb_cloned(skb)) { | |
1da177e4 | 580 | /* the copy is a forwarded packet */ |
65c88466 | 581 | if (pskb_expand_head(skb, 0, 0, GFP_ATOMIC)) { |
1d015503 ED |
582 | __IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)), |
583 | IPSTATS_MIB_OUTDISCARDS); | |
a11d206d | 584 | kfree_skb(skb); |
1da177e4 LT |
585 | return -1; |
586 | } | |
65c88466 | 587 | hdr = (struct ipv6_rt_hdr *)skb_transport_header(skb); |
1da177e4 LT |
588 | } |
589 | ||
84fa7933 | 590 | if (skb->ip_summed == CHECKSUM_COMPLETE) |
1da177e4 LT |
591 | skb->ip_summed = CHECKSUM_NONE; |
592 | ||
593 | i = n - --hdr->segments_left; | |
594 | ||
595 | rthdr = (struct rt0_hdr *) hdr; | |
596 | addr = rthdr->addr; | |
597 | addr += i - 1; | |
598 | ||
65d4ed92 | 599 | switch (hdr->type) { |
07a93626 | 600 | #if IS_ENABLED(CONFIG_IPV6_MIP6) |
65d4ed92 MN |
601 | case IPV6_SRCRT_TYPE_2: |
602 | if (xfrm6_input_addr(skb, (xfrm_address_t *)addr, | |
0660e03f | 603 | (xfrm_address_t *)&ipv6_hdr(skb)->saddr, |
65d4ed92 | 604 | IPPROTO_ROUTING) < 0) { |
1d015503 ED |
605 | __IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)), |
606 | IPSTATS_MIB_INADDRERRORS); | |
65d4ed92 MN |
607 | kfree_skb(skb); |
608 | return -1; | |
609 | } | |
adf30907 | 610 | if (!ipv6_chk_home_addr(dev_net(skb_dst(skb)->dev), addr)) { |
1d015503 ED |
611 | __IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)), |
612 | IPSTATS_MIB_INADDRERRORS); | |
65d4ed92 MN |
613 | kfree_skb(skb); |
614 | return -1; | |
615 | } | |
616 | break; | |
617 | #endif | |
618 | default: | |
619 | break; | |
620 | } | |
621 | ||
1da177e4 | 622 | if (ipv6_addr_is_multicast(addr)) { |
1d015503 ED |
623 | __IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)), |
624 | IPSTATS_MIB_INADDRERRORS); | |
1da177e4 LT |
625 | kfree_skb(skb); |
626 | return -1; | |
627 | } | |
628 | ||
4e3fd7a0 AD |
629 | daddr = *addr; |
630 | *addr = ipv6_hdr(skb)->daddr; | |
631 | ipv6_hdr(skb)->daddr = daddr; | |
1da177e4 | 632 | |
adf30907 | 633 | skb_dst_drop(skb); |
1da177e4 | 634 | ip6_route_input(skb); |
adf30907 | 635 | if (skb_dst(skb)->error) { |
d56f90a7 | 636 | skb_push(skb, skb->data - skb_network_header(skb)); |
1da177e4 LT |
637 | dst_input(skb); |
638 | return -1; | |
639 | } | |
640 | ||
adf30907 | 641 | if (skb_dst(skb)->dev->flags&IFF_LOOPBACK) { |
0660e03f | 642 | if (ipv6_hdr(skb)->hop_limit <= 1) { |
1d015503 ED |
643 | __IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)), |
644 | IPSTATS_MIB_INHDRERRORS); | |
1da177e4 | 645 | icmpv6_send(skb, ICMPV6_TIME_EXCEED, ICMPV6_EXC_HOPLIMIT, |
3ffe533c | 646 | 0); |
1da177e4 LT |
647 | kfree_skb(skb); |
648 | return -1; | |
649 | } | |
0660e03f | 650 | ipv6_hdr(skb)->hop_limit--; |
1da177e4 LT |
651 | goto looped_back; |
652 | } | |
653 | ||
d56f90a7 | 654 | skb_push(skb, skb->data - skb_network_header(skb)); |
1da177e4 LT |
655 | dst_input(skb); |
656 | return -1; | |
c382bb9d YH |
657 | |
658 | unknown_rh: | |
1d015503 | 659 | __IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)), IPSTATS_MIB_INHDRERRORS); |
c382bb9d YH |
660 | icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, |
661 | (&hdr->type) - skb_network_header(skb)); | |
662 | return -1; | |
1da177e4 LT |
663 | } |
664 | ||
41135cc8 | 665 | static const struct inet6_protocol rthdr_protocol = { |
1da177e4 | 666 | .handler = ipv6_rthdr_rcv, |
2207afc8 | 667 | .flags = INET6_PROTO_NOPOLICY, |
8ca896cf VY |
668 | }; |
669 | ||
41135cc8 | 670 | static const struct inet6_protocol destopt_protocol = { |
248b238d | 671 | .handler = ipv6_destopt_rcv, |
2207afc8 | 672 | .flags = INET6_PROTO_NOPOLICY, |
8ca896cf VY |
673 | }; |
674 | ||
41135cc8 | 675 | static const struct inet6_protocol nodata_protocol = { |
248b238d DL |
676 | .handler = dst_discard, |
677 | .flags = INET6_PROTO_NOPOLICY, | |
678 | }; | |
679 | ||
680 | int __init ipv6_exthdrs_init(void) | |
1da177e4 | 681 | { |
248b238d DL |
682 | int ret; |
683 | ||
3336288a VY |
684 | ret = inet6_add_protocol(&rthdr_protocol, IPPROTO_ROUTING); |
685 | if (ret) | |
c6b641a4 | 686 | goto out; |
3336288a | 687 | |
248b238d DL |
688 | ret = inet6_add_protocol(&destopt_protocol, IPPROTO_DSTOPTS); |
689 | if (ret) | |
690 | goto out_rthdr; | |
691 | ||
692 | ret = inet6_add_protocol(&nodata_protocol, IPPROTO_NONE); | |
693 | if (ret) | |
694 | goto out_destopt; | |
695 | ||
696 | out: | |
697 | return ret; | |
248b238d DL |
698 | out_destopt: |
699 | inet6_del_protocol(&destopt_protocol, IPPROTO_DSTOPTS); | |
3336288a VY |
700 | out_rthdr: |
701 | inet6_del_protocol(&rthdr_protocol, IPPROTO_ROUTING); | |
248b238d | 702 | goto out; |
1da177e4 LT |
703 | }; |
704 | ||
248b238d DL |
705 | void ipv6_exthdrs_exit(void) |
706 | { | |
707 | inet6_del_protocol(&nodata_protocol, IPPROTO_NONE); | |
708 | inet6_del_protocol(&destopt_protocol, IPPROTO_DSTOPTS); | |
709 | inet6_del_protocol(&rthdr_protocol, IPPROTO_ROUTING); | |
710 | } | |
711 | ||
1da177e4 LT |
712 | /********************************** |
713 | Hop-by-hop options. | |
714 | **********************************/ | |
715 | ||
e76b2b25 | 716 | /* |
adf30907 | 717 | * Note: we cannot rely on skb_dst(skb) before we assign it in ip6_route_input(). |
e76b2b25 YH |
718 | */ |
719 | static inline struct inet6_dev *ipv6_skb_idev(struct sk_buff *skb) | |
720 | { | |
adf30907 | 721 | return skb_dst(skb) ? ip6_dst_idev(skb_dst(skb)) : __in6_dev_get(skb->dev); |
e76b2b25 YH |
722 | } |
723 | ||
2570a4f5 DM |
724 | static inline struct net *ipv6_skb_net(struct sk_buff *skb) |
725 | { | |
726 | return skb_dst(skb) ? dev_net(skb_dst(skb)->dev) : dev_net(skb->dev); | |
727 | } | |
728 | ||
1da177e4 LT |
729 | /* Router Alert as of RFC 2711 */ |
730 | ||
a50feda5 | 731 | static bool ipv6_hop_ra(struct sk_buff *skb, int optoff) |
1da177e4 | 732 | { |
d56f90a7 | 733 | const unsigned char *nh = skb_network_header(skb); |
a80ff03e | 734 | |
d56f90a7 | 735 | if (nh[optoff + 1] == 2) { |
dd3332bf YH |
736 | IP6CB(skb)->flags |= IP6SKB_ROUTERALERT; |
737 | memcpy(&IP6CB(skb)->ra, nh + optoff + 2, sizeof(IP6CB(skb)->ra)); | |
a50feda5 | 738 | return true; |
1da177e4 | 739 | } |
ba7a46f1 JP |
740 | net_dbg_ratelimited("ipv6_hop_ra: wrong RA length %d\n", |
741 | nh[optoff + 1]); | |
1da177e4 | 742 | kfree_skb(skb); |
a50feda5 | 743 | return false; |
1da177e4 LT |
744 | } |
745 | ||
746 | /* Jumbo payload */ | |
747 | ||
a50feda5 | 748 | static bool ipv6_hop_jumbo(struct sk_buff *skb, int optoff) |
1da177e4 | 749 | { |
d56f90a7 | 750 | const unsigned char *nh = skb_network_header(skb); |
2570a4f5 | 751 | struct net *net = ipv6_skb_net(skb); |
1da177e4 LT |
752 | u32 pkt_len; |
753 | ||
d56f90a7 | 754 | if (nh[optoff + 1] != 4 || (optoff & 3) != 2) { |
ba7a46f1 JP |
755 | net_dbg_ratelimited("ipv6_hop_jumbo: wrong jumbo opt length/alignment %d\n", |
756 | nh[optoff+1]); | |
1d015503 ED |
757 | __IP6_INC_STATS(net, ipv6_skb_idev(skb), |
758 | IPSTATS_MIB_INHDRERRORS); | |
1da177e4 LT |
759 | goto drop; |
760 | } | |
761 | ||
d56f90a7 | 762 | pkt_len = ntohl(*(__be32 *)(nh + optoff + 2)); |
1da177e4 | 763 | if (pkt_len <= IPV6_MAXPLEN) { |
1d015503 ED |
764 | __IP6_INC_STATS(net, ipv6_skb_idev(skb), |
765 | IPSTATS_MIB_INHDRERRORS); | |
1da177e4 | 766 | icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, optoff+2); |
a50feda5 | 767 | return false; |
1da177e4 | 768 | } |
0660e03f | 769 | if (ipv6_hdr(skb)->payload_len) { |
1d015503 ED |
770 | __IP6_INC_STATS(net, ipv6_skb_idev(skb), |
771 | IPSTATS_MIB_INHDRERRORS); | |
1da177e4 | 772 | icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, optoff); |
a50feda5 | 773 | return false; |
1da177e4 LT |
774 | } |
775 | ||
776 | if (pkt_len > skb->len - sizeof(struct ipv6hdr)) { | |
1d015503 ED |
777 | __IP6_INC_STATS(net, ipv6_skb_idev(skb), |
778 | IPSTATS_MIB_INTRUNCATEDPKTS); | |
1da177e4 LT |
779 | goto drop; |
780 | } | |
42ca89c1 SH |
781 | |
782 | if (pskb_trim_rcsum(skb, pkt_len + sizeof(struct ipv6hdr))) | |
783 | goto drop; | |
784 | ||
a50feda5 | 785 | return true; |
1da177e4 LT |
786 | |
787 | drop: | |
788 | kfree_skb(skb); | |
a50feda5 | 789 | return false; |
1da177e4 LT |
790 | } |
791 | ||
2e532b70 HD |
792 | /* CALIPSO RFC 5570 */ |
793 | ||
794 | static bool ipv6_hop_calipso(struct sk_buff *skb, int optoff) | |
795 | { | |
796 | const unsigned char *nh = skb_network_header(skb); | |
797 | ||
798 | if (nh[optoff + 1] < 8) | |
799 | goto drop; | |
800 | ||
801 | if (nh[optoff + 6] * 4 + 8 > nh[optoff + 1]) | |
802 | goto drop; | |
803 | ||
804 | if (!calipso_validate(skb, nh + optoff)) | |
805 | goto drop; | |
806 | ||
807 | return true; | |
808 | ||
809 | drop: | |
810 | kfree_skb(skb); | |
811 | return false; | |
812 | } | |
813 | ||
a50feda5 | 814 | static const struct tlvtype_proc tlvprochopopt_lst[] = { |
1da177e4 LT |
815 | { |
816 | .type = IPV6_TLV_ROUTERALERT, | |
817 | .func = ipv6_hop_ra, | |
818 | }, | |
819 | { | |
820 | .type = IPV6_TLV_JUMBO, | |
821 | .func = ipv6_hop_jumbo, | |
822 | }, | |
2e532b70 HD |
823 | { |
824 | .type = IPV6_TLV_CALIPSO, | |
825 | .func = ipv6_hop_calipso, | |
826 | }, | |
1da177e4 LT |
827 | { -1, } |
828 | }; | |
829 | ||
e5bbef20 | 830 | int ipv6_parse_hopopts(struct sk_buff *skb) |
1da177e4 | 831 | { |
951dbc8a PM |
832 | struct inet6_skb_parm *opt = IP6CB(skb); |
833 | ||
ec670095 | 834 | /* |
d56f90a7 | 835 | * skb_network_header(skb) is equal to skb->data, and |
cfe1fc77 | 836 | * skb_network_header_len(skb) is always equal to |
ec670095 YH |
837 | * sizeof(struct ipv6hdr) by definition of |
838 | * hop-by-hop options. | |
839 | */ | |
840 | if (!pskb_may_pull(skb, sizeof(struct ipv6hdr) + 8) || | |
9c70220b ACM |
841 | !pskb_may_pull(skb, (sizeof(struct ipv6hdr) + |
842 | ((skb_transport_header(skb)[1] + 1) << 3)))) { | |
ec670095 YH |
843 | kfree_skb(skb); |
844 | return -1; | |
845 | } | |
846 | ||
8b58a398 | 847 | opt->flags |= IP6SKB_HOPBYHOP; |
e5bbef20 | 848 | if (ip6_parse_tlv(tlvprochopopt_lst, skb)) { |
b0e380b1 | 849 | skb->transport_header += (skb_transport_header(skb)[1] + 1) << 3; |
dc435e6d | 850 | opt = IP6CB(skb); |
951dbc8a | 851 | opt->nhoff = sizeof(struct ipv6hdr); |
b809739a | 852 | return 1; |
951dbc8a | 853 | } |
1da177e4 LT |
854 | return -1; |
855 | } | |
856 | ||
857 | /* | |
858 | * Creating outbound headers. | |
859 | * | |
860 | * "build" functions work when skb is filled from head to tail (datagram) | |
861 | * "push" functions work when headers are added from tail to head (tcp) | |
862 | * | |
863 | * In both cases we assume, that caller reserved enough room | |
864 | * for headers. | |
865 | */ | |
866 | ||
867 | static void ipv6_push_rthdr(struct sk_buff *skb, u8 *proto, | |
868 | struct ipv6_rt_hdr *opt, | |
869 | struct in6_addr **addr_p) | |
870 | { | |
871 | struct rt0_hdr *phdr, *ihdr; | |
872 | int hops; | |
873 | ||
874 | ihdr = (struct rt0_hdr *) opt; | |
1ab1457c | 875 | |
1da177e4 LT |
876 | phdr = (struct rt0_hdr *) skb_push(skb, (ihdr->rt_hdr.hdrlen + 1) << 3); |
877 | memcpy(phdr, ihdr, sizeof(struct rt0_hdr)); | |
878 | ||
879 | hops = ihdr->rt_hdr.hdrlen >> 1; | |
880 | ||
881 | if (hops > 1) | |
882 | memcpy(phdr->addr, ihdr->addr + 1, | |
883 | (hops - 1) * sizeof(struct in6_addr)); | |
884 | ||
4e3fd7a0 | 885 | phdr->addr[hops - 1] = **addr_p; |
1da177e4 LT |
886 | *addr_p = ihdr->addr; |
887 | ||
888 | phdr->rt_hdr.nexthdr = *proto; | |
889 | *proto = NEXTHDR_ROUTING; | |
890 | } | |
891 | ||
892 | static void ipv6_push_exthdr(struct sk_buff *skb, u8 *proto, u8 type, struct ipv6_opt_hdr *opt) | |
893 | { | |
894 | struct ipv6_opt_hdr *h = (struct ipv6_opt_hdr *)skb_push(skb, ipv6_optlen(opt)); | |
895 | ||
896 | memcpy(h, opt, ipv6_optlen(opt)); | |
897 | h->nexthdr = *proto; | |
898 | *proto = type; | |
899 | } | |
900 | ||
901 | void ipv6_push_nfrag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt, | |
902 | u8 *proto, | |
903 | struct in6_addr **daddr) | |
904 | { | |
333fad53 | 905 | if (opt->srcrt) { |
1da177e4 | 906 | ipv6_push_rthdr(skb, proto, opt->srcrt, daddr); |
333fad53 YH |
907 | /* |
908 | * IPV6_RTHDRDSTOPTS is ignored | |
909 | * unless IPV6_RTHDR is set (RFC3542). | |
910 | */ | |
911 | if (opt->dst0opt) | |
912 | ipv6_push_exthdr(skb, proto, NEXTHDR_DEST, opt->dst0opt); | |
913 | } | |
1da177e4 LT |
914 | if (opt->hopopt) |
915 | ipv6_push_exthdr(skb, proto, NEXTHDR_HOP, opt->hopopt); | |
916 | } | |
7159039a YH |
917 | EXPORT_SYMBOL(ipv6_push_nfrag_opts); |
918 | ||
1da177e4 LT |
919 | void ipv6_push_frag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt, u8 *proto) |
920 | { | |
921 | if (opt->dst1opt) | |
922 | ipv6_push_exthdr(skb, proto, NEXTHDR_DEST, opt->dst1opt); | |
923 | } | |
924 | ||
925 | struct ipv6_txoptions * | |
926 | ipv6_dup_options(struct sock *sk, struct ipv6_txoptions *opt) | |
927 | { | |
928 | struct ipv6_txoptions *opt2; | |
929 | ||
930 | opt2 = sock_kmalloc(sk, opt->tot_len, GFP_ATOMIC); | |
931 | if (opt2) { | |
ac3c8172 | 932 | long dif = (char *)opt2 - (char *)opt; |
1da177e4 LT |
933 | memcpy(opt2, opt, opt->tot_len); |
934 | if (opt2->hopopt) | |
ac3c8172 | 935 | *((char **)&opt2->hopopt) += dif; |
1da177e4 | 936 | if (opt2->dst0opt) |
ac3c8172 | 937 | *((char **)&opt2->dst0opt) += dif; |
1da177e4 | 938 | if (opt2->dst1opt) |
ac3c8172 | 939 | *((char **)&opt2->dst1opt) += dif; |
1da177e4 | 940 | if (opt2->srcrt) |
ac3c8172 | 941 | *((char **)&opt2->srcrt) += dif; |
45f6fad8 | 942 | atomic_set(&opt2->refcnt, 1); |
1da177e4 LT |
943 | } |
944 | return opt2; | |
945 | } | |
3cf3dc6c ACM |
946 | EXPORT_SYMBOL_GPL(ipv6_dup_options); |
947 | ||
333fad53 YH |
948 | static int ipv6_renew_option(void *ohdr, |
949 | struct ipv6_opt_hdr __user *newopt, int newoptlen, | |
950 | int inherit, | |
951 | struct ipv6_opt_hdr **hdr, | |
952 | char **p) | |
953 | { | |
954 | if (inherit) { | |
955 | if (ohdr) { | |
956 | memcpy(*p, ohdr, ipv6_optlen((struct ipv6_opt_hdr *)ohdr)); | |
957 | *hdr = (struct ipv6_opt_hdr *)*p; | |
e3192690 | 958 | *p += CMSG_ALIGN(ipv6_optlen(*hdr)); |
333fad53 YH |
959 | } |
960 | } else { | |
961 | if (newopt) { | |
962 | if (copy_from_user(*p, newopt, newoptlen)) | |
963 | return -EFAULT; | |
964 | *hdr = (struct ipv6_opt_hdr *)*p; | |
e3192690 | 965 | if (ipv6_optlen(*hdr) > newoptlen) |
333fad53 YH |
966 | return -EINVAL; |
967 | *p += CMSG_ALIGN(newoptlen); | |
968 | } | |
969 | } | |
970 | return 0; | |
971 | } | |
972 | ||
e67ae213 HD |
973 | /** |
974 | * ipv6_renew_options - replace a specific ext hdr with a new one. | |
975 | * | |
976 | * @sk: sock from which to allocate memory | |
977 | * @opt: original options | |
978 | * @newtype: option type to replace in @opt | |
979 | * @newopt: new option of type @newtype to replace (user-mem) | |
980 | * @newoptlen: length of @newopt | |
981 | * | |
982 | * Returns a new set of options which is a copy of @opt with the | |
983 | * option type @newtype replaced with @newopt. | |
984 | * | |
985 | * @opt may be NULL, in which case a new set of options is returned | |
986 | * containing just @newopt. | |
987 | * | |
988 | * @newopt may be NULL, in which case the specified option type is | |
989 | * not copied into the new set of options. | |
990 | * | |
991 | * The new set of options is allocated from the socket option memory | |
992 | * buffer of @sk. | |
993 | */ | |
333fad53 YH |
994 | struct ipv6_txoptions * |
995 | ipv6_renew_options(struct sock *sk, struct ipv6_txoptions *opt, | |
996 | int newtype, | |
997 | struct ipv6_opt_hdr __user *newopt, int newoptlen) | |
998 | { | |
999 | int tot_len = 0; | |
1000 | char *p; | |
1001 | struct ipv6_txoptions *opt2; | |
1002 | int err; | |
1003 | ||
99c7bc01 YH |
1004 | if (opt) { |
1005 | if (newtype != IPV6_HOPOPTS && opt->hopopt) | |
1006 | tot_len += CMSG_ALIGN(ipv6_optlen(opt->hopopt)); | |
1007 | if (newtype != IPV6_RTHDRDSTOPTS && opt->dst0opt) | |
1008 | tot_len += CMSG_ALIGN(ipv6_optlen(opt->dst0opt)); | |
1009 | if (newtype != IPV6_RTHDR && opt->srcrt) | |
1010 | tot_len += CMSG_ALIGN(ipv6_optlen(opt->srcrt)); | |
1011 | if (newtype != IPV6_DSTOPTS && opt->dst1opt) | |
1012 | tot_len += CMSG_ALIGN(ipv6_optlen(opt->dst1opt)); | |
1013 | } | |
1014 | ||
333fad53 YH |
1015 | if (newopt && newoptlen) |
1016 | tot_len += CMSG_ALIGN(newoptlen); | |
1017 | ||
1018 | if (!tot_len) | |
1019 | return NULL; | |
1020 | ||
8b8aa4b5 | 1021 | tot_len += sizeof(*opt2); |
333fad53 YH |
1022 | opt2 = sock_kmalloc(sk, tot_len, GFP_ATOMIC); |
1023 | if (!opt2) | |
1024 | return ERR_PTR(-ENOBUFS); | |
1025 | ||
1026 | memset(opt2, 0, tot_len); | |
45f6fad8 | 1027 | atomic_set(&opt2->refcnt, 1); |
333fad53 YH |
1028 | opt2->tot_len = tot_len; |
1029 | p = (char *)(opt2 + 1); | |
1030 | ||
99c7bc01 | 1031 | err = ipv6_renew_option(opt ? opt->hopopt : NULL, newopt, newoptlen, |
333fad53 YH |
1032 | newtype != IPV6_HOPOPTS, |
1033 | &opt2->hopopt, &p); | |
1034 | if (err) | |
1035 | goto out; | |
1036 | ||
99c7bc01 | 1037 | err = ipv6_renew_option(opt ? opt->dst0opt : NULL, newopt, newoptlen, |
333fad53 YH |
1038 | newtype != IPV6_RTHDRDSTOPTS, |
1039 | &opt2->dst0opt, &p); | |
1040 | if (err) | |
1041 | goto out; | |
1042 | ||
99c7bc01 | 1043 | err = ipv6_renew_option(opt ? opt->srcrt : NULL, newopt, newoptlen, |
333fad53 | 1044 | newtype != IPV6_RTHDR, |
99c7bc01 | 1045 | (struct ipv6_opt_hdr **)&opt2->srcrt, &p); |
333fad53 YH |
1046 | if (err) |
1047 | goto out; | |
1048 | ||
99c7bc01 | 1049 | err = ipv6_renew_option(opt ? opt->dst1opt : NULL, newopt, newoptlen, |
333fad53 YH |
1050 | newtype != IPV6_DSTOPTS, |
1051 | &opt2->dst1opt, &p); | |
1052 | if (err) | |
1053 | goto out; | |
1054 | ||
1055 | opt2->opt_nflen = (opt2->hopopt ? ipv6_optlen(opt2->hopopt) : 0) + | |
1056 | (opt2->dst0opt ? ipv6_optlen(opt2->dst0opt) : 0) + | |
1057 | (opt2->srcrt ? ipv6_optlen(opt2->srcrt) : 0); | |
1058 | opt2->opt_flen = (opt2->dst1opt ? ipv6_optlen(opt2->dst1opt) : 0); | |
1059 | ||
1060 | return opt2; | |
1061 | out: | |
8b8aa4b5 | 1062 | sock_kfree_s(sk, opt2, opt2->tot_len); |
333fad53 YH |
1063 | return ERR_PTR(err); |
1064 | } | |
1065 | ||
e67ae213 HD |
1066 | /** |
1067 | * ipv6_renew_options_kern - replace a specific ext hdr with a new one. | |
1068 | * | |
1069 | * @sk: sock from which to allocate memory | |
1070 | * @opt: original options | |
1071 | * @newtype: option type to replace in @opt | |
1072 | * @newopt: new option of type @newtype to replace (kernel-mem) | |
1073 | * @newoptlen: length of @newopt | |
1074 | * | |
1075 | * See ipv6_renew_options(). The difference is that @newopt is | |
1076 | * kernel memory, rather than user memory. | |
1077 | */ | |
1078 | struct ipv6_txoptions * | |
1079 | ipv6_renew_options_kern(struct sock *sk, struct ipv6_txoptions *opt, | |
1080 | int newtype, struct ipv6_opt_hdr *newopt, | |
1081 | int newoptlen) | |
1082 | { | |
1083 | struct ipv6_txoptions *ret_val; | |
1084 | const mm_segment_t old_fs = get_fs(); | |
1085 | ||
1086 | set_fs(KERNEL_DS); | |
1087 | ret_val = ipv6_renew_options(sk, opt, newtype, | |
1088 | (struct ipv6_opt_hdr __user *)newopt, | |
1089 | newoptlen); | |
1090 | set_fs(old_fs); | |
1091 | return ret_val; | |
1092 | } | |
1093 | ||
df9890c3 YH |
1094 | struct ipv6_txoptions *ipv6_fixup_options(struct ipv6_txoptions *opt_space, |
1095 | struct ipv6_txoptions *opt) | |
1096 | { | |
1097 | /* | |
1098 | * ignore the dest before srcrt unless srcrt is being included. | |
1099 | * --yoshfuji | |
1100 | */ | |
1101 | if (opt && opt->dst0opt && !opt->srcrt) { | |
1102 | if (opt_space != opt) { | |
1103 | memcpy(opt_space, opt, sizeof(*opt_space)); | |
1104 | opt = opt_space; | |
1105 | } | |
1106 | opt->opt_nflen -= ipv6_optlen(opt->dst0opt); | |
1107 | opt->dst0opt = NULL; | |
1108 | } | |
1109 | ||
1110 | return opt; | |
1111 | } | |
a495f836 | 1112 | EXPORT_SYMBOL_GPL(ipv6_fixup_options); |
df9890c3 | 1113 | |
20c59de2 AE |
1114 | /** |
1115 | * fl6_update_dst - update flowi destination address with info given | |
1116 | * by srcrt option, if any. | |
1117 | * | |
4c9483b2 | 1118 | * @fl6: flowi6 for which daddr is to be updated |
20c59de2 | 1119 | * @opt: struct ipv6_txoptions in which to look for srcrt opt |
4c9483b2 | 1120 | * @orig: copy of original daddr address if modified |
20c59de2 AE |
1121 | * |
1122 | * Returns NULL if no txoptions or no srcrt, otherwise returns orig | |
4c9483b2 | 1123 | * and initial value of fl6->daddr set in orig |
20c59de2 | 1124 | */ |
4c9483b2 | 1125 | struct in6_addr *fl6_update_dst(struct flowi6 *fl6, |
20c59de2 AE |
1126 | const struct ipv6_txoptions *opt, |
1127 | struct in6_addr *orig) | |
1128 | { | |
1129 | if (!opt || !opt->srcrt) | |
1130 | return NULL; | |
1131 | ||
4e3fd7a0 AD |
1132 | *orig = fl6->daddr; |
1133 | fl6->daddr = *((struct rt0_hdr *)opt->srcrt)->addr; | |
20c59de2 AE |
1134 | return orig; |
1135 | } | |
20c59de2 | 1136 | EXPORT_SYMBOL_GPL(fl6_update_dst); |