net: replace %p6 with %pI6
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / net / ipv6 / icmp.c
CommitLineData
1da177e4
LT
1/*
2 * Internet Control Message Protocol (ICMPv6)
3 * Linux INET6 implementation
4 *
5 * Authors:
6 * Pedro Roque <roque@di.fc.ul.pt>
7 *
1da177e4
LT
8 * Based on net/ipv4/icmp.c
9 *
10 * RFC 1885
11 *
12 * This program is free software; you can redistribute it and/or
13 * modify it under the terms of the GNU General Public License
14 * as published by the Free Software Foundation; either version
15 * 2 of the License, or (at your option) any later version.
16 */
17
18/*
19 * Changes:
20 *
21 * Andi Kleen : exception handling
22 * Andi Kleen add rate limits. never reply to a icmp.
23 * add more length checks and other fixes.
24 * yoshfuji : ensure to sent parameter problem for
25 * fragments.
26 * YOSHIFUJI Hideaki @USAGI: added sysctl for icmp rate limit.
27 * Randy Dunlap and
28 * YOSHIFUJI Hideaki @USAGI: Per-interface statistics support
29 * Kazunori MIYAZAWA @USAGI: change output process to use ip6_append_data
30 */
31
32#include <linux/module.h>
33#include <linux/errno.h>
34#include <linux/types.h>
35#include <linux/socket.h>
36#include <linux/in.h>
37#include <linux/kernel.h>
1da177e4
LT
38#include <linux/sockios.h>
39#include <linux/net.h>
40#include <linux/skbuff.h>
41#include <linux/init.h>
763ecff1 42#include <linux/netfilter.h>
1da177e4
LT
43
44#ifdef CONFIG_SYSCTL
45#include <linux/sysctl.h>
46#endif
47
48#include <linux/inet.h>
49#include <linux/netdevice.h>
50#include <linux/icmpv6.h>
51
52#include <net/ip.h>
53#include <net/sock.h>
54
55#include <net/ipv6.h>
56#include <net/ip6_checksum.h>
57#include <net/protocol.h>
58#include <net/raw.h>
59#include <net/rawv6.h>
60#include <net/transp_v6.h>
61#include <net/ip6_route.h>
62#include <net/addrconf.h>
63#include <net/icmp.h>
8b7817f3 64#include <net/xfrm.h>
1ed8516f 65#include <net/inet_common.h>
1da177e4
LT
66
67#include <asm/uaccess.h>
68#include <asm/system.h>
69
ba89966c 70DEFINE_SNMP_STAT(struct icmpv6_mib, icmpv6_statistics) __read_mostly;
7159039a 71EXPORT_SYMBOL(icmpv6_statistics);
14878f75
DS
72DEFINE_SNMP_STAT(struct icmpv6msg_mib, icmpv6msg_statistics) __read_mostly;
73EXPORT_SYMBOL(icmpv6msg_statistics);
1da177e4
LT
74
75/*
76 * The ICMP socket(s). This is the most convenient way to flow control
77 * our ICMP output as well as maintain a clean interface throughout
78 * all layers. All Socketless IP sends will soon be gone.
79 *
80 * On SMP we have one ICMP socket per-cpu.
81 */
98c6d1b2
DL
82static inline struct sock *icmpv6_sk(struct net *net)
83{
84 return net->ipv6.icmp_sk[smp_processor_id()];
85}
1da177e4 86
e5bbef20 87static int icmpv6_rcv(struct sk_buff *skb);
1da177e4
LT
88
89static struct inet6_protocol icmpv6_protocol = {
90 .handler = icmpv6_rcv,
8b7817f3 91 .flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
1da177e4
LT
92};
93
fdc0bde9 94static __inline__ struct sock *icmpv6_xmit_lock(struct net *net)
1da177e4 95{
fdc0bde9
DL
96 struct sock *sk;
97
1da177e4
LT
98 local_bh_disable();
99
fdc0bde9 100 sk = icmpv6_sk(net);
405666db 101 if (unlikely(!spin_trylock(&sk->sk_lock.slock))) {
1da177e4
LT
102 /* This can happen if the output path (f.e. SIT or
103 * ip6ip6 tunnel) signals dst_link_failure() for an
104 * outgoing ICMP6 packet.
105 */
106 local_bh_enable();
fdc0bde9 107 return NULL;
1da177e4 108 }
fdc0bde9 109 return sk;
1da177e4
LT
110}
111
405666db 112static __inline__ void icmpv6_xmit_unlock(struct sock *sk)
1da177e4 113{
405666db 114 spin_unlock_bh(&sk->sk_lock.slock);
1da177e4
LT
115}
116
1ab1457c 117/*
1da177e4
LT
118 * Slightly more convenient version of icmpv6_send.
119 */
120void icmpv6_param_prob(struct sk_buff *skb, int code, int pos)
121{
122 icmpv6_send(skb, ICMPV6_PARAMPROB, code, pos, skb->dev);
123 kfree_skb(skb);
124}
125
126/*
127 * Figure out, may we reply to this packet with icmp error.
128 *
129 * We do not reply, if:
130 * - it was icmp error message.
131 * - it is truncated, so that it is known, that protocol is ICMPV6
132 * (i.e. in the middle of some exthdr)
133 *
134 * --ANK (980726)
135 */
136
137static int is_ineligible(struct sk_buff *skb)
138{
0660e03f 139 int ptr = (u8 *)(ipv6_hdr(skb) + 1) - skb->data;
1da177e4 140 int len = skb->len - ptr;
0660e03f 141 __u8 nexthdr = ipv6_hdr(skb)->nexthdr;
1da177e4
LT
142
143 if (len < 0)
144 return 1;
145
0d3d077c 146 ptr = ipv6_skip_exthdr(skb, ptr, &nexthdr);
1da177e4
LT
147 if (ptr < 0)
148 return 0;
149 if (nexthdr == IPPROTO_ICMPV6) {
150 u8 _type, *tp;
151 tp = skb_header_pointer(skb,
152 ptr+offsetof(struct icmp6hdr, icmp6_type),
153 sizeof(_type), &_type);
154 if (tp == NULL ||
155 !(*tp & ICMPV6_INFOMSG_MASK))
156 return 1;
157 }
158 return 0;
159}
160
1ab1457c
YH
161/*
162 * Check the ICMP output rate limit
1da177e4
LT
163 */
164static inline int icmpv6_xrlim_allow(struct sock *sk, int type,
165 struct flowi *fl)
166{
167 struct dst_entry *dst;
3b1e0a65 168 struct net *net = sock_net(sk);
1da177e4
LT
169 int res = 0;
170
171 /* Informational messages are not limited. */
172 if (type & ICMPV6_INFOMSG_MASK)
173 return 1;
174
175 /* Do not limit pmtu discovery, it would break it. */
176 if (type == ICMPV6_PKT_TOOBIG)
177 return 1;
178
1ab1457c 179 /*
1da177e4
LT
180 * Look up the output route.
181 * XXX: perhaps the expire for routing entries cloned by
182 * this lookup should be more aggressive (not longer than timeout).
183 */
9a43b709 184 dst = ip6_route_output(net, sk, fl);
1da177e4 185 if (dst->error) {
3bd653c8 186 IP6_INC_STATS(net, ip6_dst_idev(dst),
a11d206d 187 IPSTATS_MIB_OUTNOROUTES);
1da177e4
LT
188 } else if (dst->dev && (dst->dev->flags&IFF_LOOPBACK)) {
189 res = 1;
190 } else {
191 struct rt6_info *rt = (struct rt6_info *)dst;
9a43b709 192 int tmo = net->ipv6.sysctl.icmpv6_time;
1da177e4
LT
193
194 /* Give more bandwidth to wider prefixes. */
195 if (rt->rt6i_dst.plen < 128)
196 tmo >>= ((128 - rt->rt6i_dst.plen)>>5);
197
198 res = xrlim_allow(dst, tmo);
199 }
200 dst_release(dst);
201 return res;
202}
203
204/*
205 * an inline helper for the "simple" if statement below
206 * checks if parameter problem report is caused by an
1ab1457c 207 * unrecognized IPv6 option that has the Option Type
1da177e4
LT
208 * highest-order two bits set to 10
209 */
210
211static __inline__ int opt_unrec(struct sk_buff *skb, __u32 offset)
212{
213 u8 _optval, *op;
214
bbe735e4 215 offset += skb_network_offset(skb);
1da177e4
LT
216 op = skb_header_pointer(skb, offset, sizeof(_optval), &_optval);
217 if (op == NULL)
218 return 1;
219 return (*op & 0xC0) == 0x80;
220}
221
222static int icmpv6_push_pending_frames(struct sock *sk, struct flowi *fl, struct icmp6hdr *thdr, int len)
223{
224 struct sk_buff *skb;
225 struct icmp6hdr *icmp6h;
226 int err = 0;
227
228 if ((skb = skb_peek(&sk->sk_write_queue)) == NULL)
229 goto out;
230
cc70ab26 231 icmp6h = icmp6_hdr(skb);
1da177e4
LT
232 memcpy(icmp6h, thdr, sizeof(struct icmp6hdr));
233 icmp6h->icmp6_cksum = 0;
234
235 if (skb_queue_len(&sk->sk_write_queue) == 1) {
236 skb->csum = csum_partial((char *)icmp6h,
237 sizeof(struct icmp6hdr), skb->csum);
238 icmp6h->icmp6_cksum = csum_ipv6_magic(&fl->fl6_src,
239 &fl->fl6_dst,
240 len, fl->proto,
241 skb->csum);
242 } else {
868c86bc 243 __wsum tmp_csum = 0;
1da177e4
LT
244
245 skb_queue_walk(&sk->sk_write_queue, skb) {
246 tmp_csum = csum_add(tmp_csum, skb->csum);
247 }
248
249 tmp_csum = csum_partial((char *)icmp6h,
250 sizeof(struct icmp6hdr), tmp_csum);
868c86bc
AV
251 icmp6h->icmp6_cksum = csum_ipv6_magic(&fl->fl6_src,
252 &fl->fl6_dst,
253 len, fl->proto,
254 tmp_csum);
1da177e4 255 }
1da177e4
LT
256 ip6_push_pending_frames(sk);
257out:
258 return err;
259}
260
261struct icmpv6_msg {
262 struct sk_buff *skb;
263 int offset;
763ecff1 264 uint8_t type;
1da177e4
LT
265};
266
267static int icmpv6_getfrag(void *from, char *to, int offset, int len, int odd, struct sk_buff *skb)
268{
269 struct icmpv6_msg *msg = (struct icmpv6_msg *) from;
270 struct sk_buff *org_skb = msg->skb;
5f92a738 271 __wsum csum = 0;
1da177e4
LT
272
273 csum = skb_copy_and_csum_bits(org_skb, msg->offset + offset,
274 to, len, csum);
275 skb->csum = csum_block_add(skb->csum, csum, odd);
763ecff1
YK
276 if (!(msg->type & ICMPV6_INFOMSG_MASK))
277 nf_ct_attach(skb, org_skb);
1da177e4
LT
278 return 0;
279}
280
59fbb3a6 281#if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
79383236
MN
282static void mip6_addr_swap(struct sk_buff *skb)
283{
0660e03f 284 struct ipv6hdr *iph = ipv6_hdr(skb);
79383236
MN
285 struct inet6_skb_parm *opt = IP6CB(skb);
286 struct ipv6_destopt_hao *hao;
287 struct in6_addr tmp;
288 int off;
289
290 if (opt->dsthao) {
291 off = ipv6_find_tlv(skb, opt->dsthao, IPV6_TLV_HAO);
292 if (likely(off >= 0)) {
d56f90a7
ACM
293 hao = (struct ipv6_destopt_hao *)
294 (skb_network_header(skb) + off);
79383236
MN
295 ipv6_addr_copy(&tmp, &iph->saddr);
296 ipv6_addr_copy(&iph->saddr, &hao->addr);
297 ipv6_addr_copy(&hao->addr, &tmp);
298 }
299 }
300}
301#else
302static inline void mip6_addr_swap(struct sk_buff *skb) {}
303#endif
304
1da177e4
LT
305/*
306 * Send an ICMP message in response to a packet in error
307 */
1ab1457c 308void icmpv6_send(struct sk_buff *skb, int type, int code, __u32 info,
1da177e4
LT
309 struct net_device *dev)
310{
c346dca1 311 struct net *net = dev_net(skb->dev);
1da177e4 312 struct inet6_dev *idev = NULL;
0660e03f 313 struct ipv6hdr *hdr = ipv6_hdr(skb);
84427d53
YH
314 struct sock *sk;
315 struct ipv6_pinfo *np;
1da177e4
LT
316 struct in6_addr *saddr = NULL;
317 struct dst_entry *dst;
8b7817f3 318 struct dst_entry *dst2;
1da177e4
LT
319 struct icmp6hdr tmp_hdr;
320 struct flowi fl;
8b7817f3 321 struct flowi fl2;
1da177e4
LT
322 struct icmpv6_msg msg;
323 int iif = 0;
324 int addr_type = 0;
325 int len;
41a1f8ea 326 int hlimit, tclass;
1da177e4
LT
327 int err = 0;
328
27a884dc
ACM
329 if ((u8 *)hdr < skb->head ||
330 (skb->network_header + sizeof(*hdr)) > skb->tail)
1da177e4
LT
331 return;
332
333 /*
1ab1457c 334 * Make sure we respect the rules
1da177e4
LT
335 * i.e. RFC 1885 2.4(e)
336 * Rule (e.1) is enforced by not using icmpv6_send
337 * in any code that processes icmp errors.
338 */
339 addr_type = ipv6_addr_type(&hdr->daddr);
340
9a43b709 341 if (ipv6_chk_addr(net, &hdr->daddr, skb->dev, 0))
1da177e4
LT
342 saddr = &hdr->daddr;
343
344 /*
345 * Dest addr check
346 */
347
348 if ((addr_type & IPV6_ADDR_MULTICAST || skb->pkt_type != PACKET_HOST)) {
349 if (type != ICMPV6_PKT_TOOBIG &&
1ab1457c
YH
350 !(type == ICMPV6_PARAMPROB &&
351 code == ICMPV6_UNK_OPTION &&
1da177e4
LT
352 (opt_unrec(skb, info))))
353 return;
354
355 saddr = NULL;
356 }
357
358 addr_type = ipv6_addr_type(&hdr->saddr);
359
360 /*
361 * Source addr check
362 */
363
364 if (addr_type & IPV6_ADDR_LINKLOCAL)
365 iif = skb->dev->ifindex;
366
367 /*
8de3351e
YH
368 * Must not send error if the source does not uniquely
369 * identify a single node (RFC2463 Section 2.4).
370 * We check unspecified / multicast addresses here,
371 * and anycast addresses will be checked later.
1da177e4
LT
372 */
373 if ((addr_type == IPV6_ADDR_ANY) || (addr_type & IPV6_ADDR_MULTICAST)) {
64ce2073 374 LIMIT_NETDEBUG(KERN_DEBUG "icmpv6_send: addr_any/mcast source\n");
1da177e4
LT
375 return;
376 }
377
1ab1457c 378 /*
1da177e4
LT
379 * Never answer to a ICMP packet.
380 */
381 if (is_ineligible(skb)) {
64ce2073 382 LIMIT_NETDEBUG(KERN_DEBUG "icmpv6_send: no reply to icmp error\n");
1da177e4
LT
383 return;
384 }
385
79383236
MN
386 mip6_addr_swap(skb);
387
1da177e4
LT
388 memset(&fl, 0, sizeof(fl));
389 fl.proto = IPPROTO_ICMPV6;
390 ipv6_addr_copy(&fl.fl6_dst, &hdr->saddr);
391 if (saddr)
392 ipv6_addr_copy(&fl.fl6_src, saddr);
393 fl.oif = iif;
394 fl.fl_icmp_type = type;
395 fl.fl_icmp_code = code;
beb8d13b 396 security_skb_classify_flow(skb, &fl);
1da177e4 397
fdc0bde9
DL
398 sk = icmpv6_xmit_lock(net);
399 if (sk == NULL)
405666db 400 return;
fdc0bde9 401 np = inet6_sk(sk);
405666db 402
1da177e4
LT
403 if (!icmpv6_xrlim_allow(sk, type, &fl))
404 goto out;
405
406 tmp_hdr.icmp6_type = type;
407 tmp_hdr.icmp6_code = code;
408 tmp_hdr.icmp6_cksum = 0;
409 tmp_hdr.icmp6_pointer = htonl(info);
410
411 if (!fl.oif && ipv6_addr_is_multicast(&fl.fl6_dst))
412 fl.oif = np->mcast_oif;
413
414 err = ip6_dst_lookup(sk, &dst, &fl);
415 if (err)
416 goto out;
8de3351e
YH
417
418 /*
419 * We won't send icmp if the destination is known
420 * anycast.
421 */
422 if (((struct rt6_info *)dst)->rt6i_flags & RTF_ANYCAST) {
423 LIMIT_NETDEBUG(KERN_DEBUG "icmpv6_send: acast source\n");
424 goto out_dst_release;
425 }
426
8b7817f3
HX
427 /* No need to clone since we're just using its address. */
428 dst2 = dst;
429
430 err = xfrm_lookup(&dst, &fl, sk, 0);
431 switch (err) {
432 case 0:
433 if (dst != dst2)
434 goto route_done;
435 break;
436 case -EPERM:
437 dst = NULL;
438 break;
439 default:
440 goto out;
441 }
442
443 if (xfrm_decode_session_reverse(skb, &fl2, AF_INET6))
af268182 444 goto relookup_failed;
8b7817f3
HX
445
446 if (ip6_dst_lookup(sk, &dst2, &fl))
af268182 447 goto relookup_failed;
1da177e4 448
8b7817f3 449 err = xfrm_lookup(&dst2, &fl, sk, XFRM_LOOKUP_ICMP);
af268182
HX
450 switch (err) {
451 case 0:
452 dst_release(dst);
453 dst = dst2;
454 break;
455 case -EPERM:
456 goto out_dst_release;
457 default:
458relookup_failed:
8b7817f3
HX
459 if (!dst)
460 goto out;
af268182 461 break;
8b7817f3
HX
462 }
463
8b7817f3 464route_done:
1da177e4
LT
465 if (ipv6_addr_is_multicast(&fl.fl6_dst))
466 hlimit = np->mcast_hops;
467 else
468 hlimit = np->hop_limit;
469 if (hlimit < 0)
6b75d090 470 hlimit = ip6_dst_hoplimit(dst);
1da177e4 471
e012d51c 472 tclass = np->tclass;
41a1f8ea
YH
473 if (tclass < 0)
474 tclass = 0;
475
1da177e4 476 msg.skb = skb;
bbe735e4 477 msg.offset = skb_network_offset(skb);
763ecff1 478 msg.type = type;
1da177e4
LT
479
480 len = skb->len - msg.offset;
481 len = min_t(unsigned int, len, IPV6_MIN_MTU - sizeof(struct ipv6hdr) -sizeof(struct icmp6hdr));
482 if (len < 0) {
64ce2073 483 LIMIT_NETDEBUG(KERN_DEBUG "icmp: len problem\n");
1da177e4
LT
484 goto out_dst_release;
485 }
486
487 idev = in6_dev_get(skb->dev);
488
489 err = ip6_append_data(sk, icmpv6_getfrag, &msg,
490 len + sizeof(struct icmp6hdr),
491 sizeof(struct icmp6hdr),
41a1f8ea 492 hlimit, tclass, NULL, &fl, (struct rt6_info*)dst,
1da177e4
LT
493 MSG_DONTWAIT);
494 if (err) {
495 ip6_flush_pending_frames(sk);
496 goto out_put;
497 }
498 err = icmpv6_push_pending_frames(sk, &fl, &tmp_hdr, len + sizeof(struct icmp6hdr));
499
1da177e4
LT
500out_put:
501 if (likely(idev != NULL))
502 in6_dev_put(idev);
503out_dst_release:
504 dst_release(dst);
505out:
405666db 506 icmpv6_xmit_unlock(sk);
1da177e4
LT
507}
508
7159039a
YH
509EXPORT_SYMBOL(icmpv6_send);
510
1da177e4
LT
511static void icmpv6_echo_reply(struct sk_buff *skb)
512{
c346dca1 513 struct net *net = dev_net(skb->dev);
84427d53 514 struct sock *sk;
1da177e4 515 struct inet6_dev *idev;
84427d53 516 struct ipv6_pinfo *np;
1da177e4 517 struct in6_addr *saddr = NULL;
cc70ab26 518 struct icmp6hdr *icmph = icmp6_hdr(skb);
1da177e4
LT
519 struct icmp6hdr tmp_hdr;
520 struct flowi fl;
521 struct icmpv6_msg msg;
522 struct dst_entry *dst;
523 int err = 0;
524 int hlimit;
41a1f8ea 525 int tclass;
1da177e4 526
0660e03f 527 saddr = &ipv6_hdr(skb)->daddr;
1da177e4
LT
528
529 if (!ipv6_unicast_destination(skb))
530 saddr = NULL;
531
532 memcpy(&tmp_hdr, icmph, sizeof(tmp_hdr));
533 tmp_hdr.icmp6_type = ICMPV6_ECHO_REPLY;
534
535 memset(&fl, 0, sizeof(fl));
536 fl.proto = IPPROTO_ICMPV6;
0660e03f 537 ipv6_addr_copy(&fl.fl6_dst, &ipv6_hdr(skb)->saddr);
1da177e4
LT
538 if (saddr)
539 ipv6_addr_copy(&fl.fl6_src, saddr);
540 fl.oif = skb->dev->ifindex;
541 fl.fl_icmp_type = ICMPV6_ECHO_REPLY;
beb8d13b 542 security_skb_classify_flow(skb, &fl);
1da177e4 543
fdc0bde9
DL
544 sk = icmpv6_xmit_lock(net);
545 if (sk == NULL)
405666db 546 return;
fdc0bde9 547 np = inet6_sk(sk);
405666db 548
1da177e4
LT
549 if (!fl.oif && ipv6_addr_is_multicast(&fl.fl6_dst))
550 fl.oif = np->mcast_oif;
551
552 err = ip6_dst_lookup(sk, &dst, &fl);
553 if (err)
554 goto out;
555 if ((err = xfrm_lookup(&dst, &fl, sk, 0)) < 0)
e104411b 556 goto out;
1da177e4
LT
557
558 if (ipv6_addr_is_multicast(&fl.fl6_dst))
559 hlimit = np->mcast_hops;
560 else
561 hlimit = np->hop_limit;
562 if (hlimit < 0)
6b75d090 563 hlimit = ip6_dst_hoplimit(dst);
1da177e4 564
e012d51c 565 tclass = np->tclass;
41a1f8ea
YH
566 if (tclass < 0)
567 tclass = 0;
568
1da177e4
LT
569 idev = in6_dev_get(skb->dev);
570
571 msg.skb = skb;
572 msg.offset = 0;
763ecff1 573 msg.type = ICMPV6_ECHO_REPLY;
1da177e4
LT
574
575 err = ip6_append_data(sk, icmpv6_getfrag, &msg, skb->len + sizeof(struct icmp6hdr),
41a1f8ea 576 sizeof(struct icmp6hdr), hlimit, tclass, NULL, &fl,
1da177e4
LT
577 (struct rt6_info*)dst, MSG_DONTWAIT);
578
579 if (err) {
580 ip6_flush_pending_frames(sk);
581 goto out_put;
582 }
583 err = icmpv6_push_pending_frames(sk, &fl, &tmp_hdr, skb->len + sizeof(struct icmp6hdr));
584
1ab1457c 585out_put:
1da177e4
LT
586 if (likely(idev != NULL))
587 in6_dev_put(idev);
1da177e4 588 dst_release(dst);
1ab1457c 589out:
405666db 590 icmpv6_xmit_unlock(sk);
1da177e4
LT
591}
592
04ce6909 593static void icmpv6_notify(struct sk_buff *skb, int type, int code, __be32 info)
1da177e4 594{
1da177e4 595 struct inet6_protocol *ipprot;
1da177e4
LT
596 int inner_offset;
597 int hash;
598 u8 nexthdr;
599
600 if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
601 return;
602
603 nexthdr = ((struct ipv6hdr *)skb->data)->nexthdr;
604 if (ipv6_ext_hdr(nexthdr)) {
605 /* now skip over extension headers */
0d3d077c 606 inner_offset = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr), &nexthdr);
1da177e4
LT
607 if (inner_offset<0)
608 return;
609 } else {
610 inner_offset = sizeof(struct ipv6hdr);
611 }
612
613 /* Checkin header including 8 bytes of inner protocol header. */
614 if (!pskb_may_pull(skb, inner_offset+8))
615 return;
616
1da177e4
LT
617 /* BUGGG_FUTURE: we should try to parse exthdrs in this packet.
618 Without this we will not able f.e. to make source routed
619 pmtu discovery.
620 Corresponding argument (opt) to notifiers is already added.
621 --ANK (980726)
622 */
623
624 hash = nexthdr & (MAX_INET_PROTOS - 1);
625
626 rcu_read_lock();
627 ipprot = rcu_dereference(inet6_protos[hash]);
628 if (ipprot && ipprot->err_handler)
629 ipprot->err_handler(skb, NULL, type, code, inner_offset, info);
630 rcu_read_unlock();
631
69d6da0b 632 raw6_icmp_error(skb, nexthdr, type, code, inner_offset, info);
1da177e4 633}
1ab1457c 634
1da177e4
LT
635/*
636 * Handle icmp messages
637 */
638
e5bbef20 639static int icmpv6_rcv(struct sk_buff *skb)
1da177e4 640{
1da177e4
LT
641 struct net_device *dev = skb->dev;
642 struct inet6_dev *idev = __in6_dev_get(dev);
643 struct in6_addr *saddr, *daddr;
644 struct ipv6hdr *orig_hdr;
645 struct icmp6hdr *hdr;
646 int type;
647
aebcf82c 648 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) {
def8b4fa 649 struct sec_path *sp = skb_sec_path(skb);
8b7817f3
HX
650 int nh;
651
def8b4fa 652 if (!(sp && sp->xvec[sp->len - 1]->props.flags &
aebcf82c
HX
653 XFRM_STATE_ICMP))
654 goto drop_no_count;
655
8b7817f3
HX
656 if (!pskb_may_pull(skb, sizeof(*hdr) + sizeof(*orig_hdr)))
657 goto drop_no_count;
658
659 nh = skb_network_offset(skb);
660 skb_set_network_header(skb, sizeof(*hdr));
661
662 if (!xfrm6_policy_check_reverse(NULL, XFRM_POLICY_IN, skb))
663 goto drop_no_count;
664
665 skb_set_network_header(skb, nh);
666 }
667
e41b5368 668 ICMP6_INC_STATS_BH(dev_net(dev), idev, ICMP6_MIB_INMSGS);
1da177e4 669
0660e03f
ACM
670 saddr = &ipv6_hdr(skb)->saddr;
671 daddr = &ipv6_hdr(skb)->daddr;
1da177e4
LT
672
673 /* Perform checksum. */
fb286bb2 674 switch (skb->ip_summed) {
84fa7933 675 case CHECKSUM_COMPLETE:
fb286bb2
HX
676 if (!csum_ipv6_magic(saddr, daddr, skb->len, IPPROTO_ICMPV6,
677 skb->csum))
678 break;
679 /* fall through */
680 case CHECKSUM_NONE:
868c86bc
AV
681 skb->csum = ~csum_unfold(csum_ipv6_magic(saddr, daddr, skb->len,
682 IPPROTO_ICMPV6, 0));
fb286bb2 683 if (__skb_checksum_complete(skb)) {
5b095d98 684 LIMIT_NETDEBUG(KERN_DEBUG "ICMPv6 checksum failed [%pI6 > %pI6]\n",
0c6ce78a 685 saddr, daddr);
1da177e4
LT
686 goto discard_it;
687 }
688 }
689
8cf22943
HX
690 if (!pskb_pull(skb, sizeof(*hdr)))
691 goto discard_it;
1da177e4 692
cc70ab26 693 hdr = icmp6_hdr(skb);
1da177e4
LT
694
695 type = hdr->icmp6_type;
696
55d43808 697 ICMP6MSGIN_INC_STATS_BH(dev_net(dev), idev, type);
1da177e4
LT
698
699 switch (type) {
700 case ICMPV6_ECHO_REQUEST:
701 icmpv6_echo_reply(skb);
702 break;
703
704 case ICMPV6_ECHO_REPLY:
705 /* we couldn't care less */
706 break;
707
708 case ICMPV6_PKT_TOOBIG:
709 /* BUGGG_FUTURE: if packet contains rthdr, we cannot update
710 standard destination cache. Seems, only "advanced"
711 destination cache will allow to solve this problem
712 --ANK (980726)
713 */
714 if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
715 goto discard_it;
cc70ab26 716 hdr = icmp6_hdr(skb);
1da177e4
LT
717 orig_hdr = (struct ipv6hdr *) (hdr + 1);
718 rt6_pmtu_discovery(&orig_hdr->daddr, &orig_hdr->saddr, dev,
719 ntohl(hdr->icmp6_mtu));
720
721 /*
722 * Drop through to notify
723 */
724
725 case ICMPV6_DEST_UNREACH:
726 case ICMPV6_TIME_EXCEED:
727 case ICMPV6_PARAMPROB:
728 icmpv6_notify(skb, type, hdr->icmp6_code, hdr->icmp6_mtu);
729 break;
730
731 case NDISC_ROUTER_SOLICITATION:
732 case NDISC_ROUTER_ADVERTISEMENT:
733 case NDISC_NEIGHBOUR_SOLICITATION:
734 case NDISC_NEIGHBOUR_ADVERTISEMENT:
735 case NDISC_REDIRECT:
736 ndisc_rcv(skb);
737 break;
738
739 case ICMPV6_MGM_QUERY:
740 igmp6_event_query(skb);
741 break;
742
743 case ICMPV6_MGM_REPORT:
744 igmp6_event_report(skb);
745 break;
746
747 case ICMPV6_MGM_REDUCTION:
748 case ICMPV6_NI_QUERY:
749 case ICMPV6_NI_REPLY:
750 case ICMPV6_MLD2_REPORT:
751 case ICMPV6_DHAAD_REQUEST:
752 case ICMPV6_DHAAD_REPLY:
753 case ICMPV6_MOBILE_PREFIX_SOL:
754 case ICMPV6_MOBILE_PREFIX_ADV:
755 break;
756
757 default:
64ce2073 758 LIMIT_NETDEBUG(KERN_DEBUG "icmpv6: msg of unknown type\n");
1da177e4
LT
759
760 /* informational */
761 if (type & ICMPV6_INFOMSG_MASK)
762 break;
763
1ab1457c
YH
764 /*
765 * error of unknown type.
766 * must pass to upper level
1da177e4
LT
767 */
768
769 icmpv6_notify(skb, type, hdr->icmp6_code, hdr->icmp6_mtu);
3ff50b79
SH
770 }
771
1da177e4
LT
772 kfree_skb(skb);
773 return 0;
774
775discard_it:
e41b5368 776 ICMP6_INC_STATS_BH(dev_net(dev), idev, ICMP6_MIB_INERRORS);
8b7817f3 777drop_no_count:
1da177e4
LT
778 kfree_skb(skb);
779 return 0;
780}
781
95e41e93
YH
782void icmpv6_flow_init(struct sock *sk, struct flowi *fl,
783 u8 type,
784 const struct in6_addr *saddr,
785 const struct in6_addr *daddr,
786 int oif)
787{
788 memset(fl, 0, sizeof(*fl));
789 ipv6_addr_copy(&fl->fl6_src, saddr);
790 ipv6_addr_copy(&fl->fl6_dst, daddr);
791 fl->proto = IPPROTO_ICMPV6;
792 fl->fl_icmp_type = type;
793 fl->fl_icmp_code = 0;
794 fl->oif = oif;
795 security_sk_classify_flow(sk, fl);
796}
797
640c41c7 798/*
b7e729c4 799 * Special lock-class for __icmpv6_sk:
640c41c7
IM
800 */
801static struct lock_class_key icmpv6_socket_sk_dst_lock_key;
802
98c6d1b2 803static int __net_init icmpv6_sk_init(struct net *net)
1da177e4
LT
804{
805 struct sock *sk;
806 int err, i, j;
807
98c6d1b2
DL
808 net->ipv6.icmp_sk =
809 kzalloc(nr_cpu_ids * sizeof(struct sock *), GFP_KERNEL);
810 if (net->ipv6.icmp_sk == NULL)
79c91159
DL
811 return -ENOMEM;
812
6f912042 813 for_each_possible_cpu(i) {
1ed8516f
DL
814 err = inet_ctl_sock_create(&sk, PF_INET6,
815 SOCK_RAW, IPPROTO_ICMPV6, net);
1da177e4
LT
816 if (err < 0) {
817 printk(KERN_ERR
818 "Failed to initialize the ICMP6 control socket "
819 "(err %d).\n",
820 err);
821 goto fail;
822 }
823
1ed8516f 824 net->ipv6.icmp_sk[i] = sk;
5c8cafd6 825
640c41c7
IM
826 /*
827 * Split off their lock-class, because sk->sk_dst_lock
828 * gets used from softirqs, which is safe for
b7e729c4 829 * __icmpv6_sk (because those never get directly used
640c41c7
IM
830 * via userspace syscalls), but unsafe for normal sockets.
831 */
832 lockdep_set_class(&sk->sk_dst_lock,
833 &icmpv6_socket_sk_dst_lock_key);
1da177e4
LT
834
835 /* Enough space for 2 64K ICMP packets, including
836 * sk_buff struct overhead.
837 */
838 sk->sk_sndbuf =
839 (2 * ((64 * 1024) + sizeof(struct sk_buff)));
1da177e4 840 }
1da177e4
LT
841 return 0;
842
843 fail:
5c8cafd6 844 for (j = 0; j < i; j++)
1ed8516f 845 inet_ctl_sock_destroy(net->ipv6.icmp_sk[j]);
98c6d1b2 846 kfree(net->ipv6.icmp_sk);
1da177e4
LT
847 return err;
848}
849
98c6d1b2 850static void __net_exit icmpv6_sk_exit(struct net *net)
1da177e4
LT
851{
852 int i;
853
6f912042 854 for_each_possible_cpu(i) {
1ed8516f 855 inet_ctl_sock_destroy(net->ipv6.icmp_sk[i]);
1da177e4 856 }
98c6d1b2
DL
857 kfree(net->ipv6.icmp_sk);
858}
859
8ed7edce 860static struct pernet_operations icmpv6_sk_ops = {
98c6d1b2
DL
861 .init = icmpv6_sk_init,
862 .exit = icmpv6_sk_exit,
863};
864
865int __init icmpv6_init(void)
866{
867 int err;
868
869 err = register_pernet_subsys(&icmpv6_sk_ops);
870 if (err < 0)
871 return err;
872
873 err = -EAGAIN;
874 if (inet6_add_protocol(&icmpv6_protocol, IPPROTO_ICMPV6) < 0)
875 goto fail;
876 return 0;
877
878fail:
879 printk(KERN_ERR "Failed to register ICMP6 protocol\n");
880 unregister_pernet_subsys(&icmpv6_sk_ops);
881 return err;
882}
883
8ed7edce 884void icmpv6_cleanup(void)
98c6d1b2
DL
885{
886 unregister_pernet_subsys(&icmpv6_sk_ops);
1da177e4
LT
887 inet6_del_protocol(&icmpv6_protocol, IPPROTO_ICMPV6);
888}
889
98c6d1b2 890
9b5b5cff 891static const struct icmp6_err {
1da177e4
LT
892 int err;
893 int fatal;
894} tab_unreach[] = {
895 { /* NOROUTE */
896 .err = ENETUNREACH,
897 .fatal = 0,
898 },
899 { /* ADM_PROHIBITED */
900 .err = EACCES,
901 .fatal = 1,
902 },
903 { /* Was NOT_NEIGHBOUR, now reserved */
904 .err = EHOSTUNREACH,
905 .fatal = 0,
906 },
907 { /* ADDR_UNREACH */
908 .err = EHOSTUNREACH,
909 .fatal = 0,
910 },
911 { /* PORT_UNREACH */
912 .err = ECONNREFUSED,
913 .fatal = 1,
914 },
915};
916
917int icmpv6_err_convert(int type, int code, int *err)
918{
919 int fatal = 0;
920
921 *err = EPROTO;
922
923 switch (type) {
924 case ICMPV6_DEST_UNREACH:
925 fatal = 1;
926 if (code <= ICMPV6_PORT_UNREACH) {
927 *err = tab_unreach[code].err;
928 fatal = tab_unreach[code].fatal;
929 }
930 break;
931
932 case ICMPV6_PKT_TOOBIG:
933 *err = EMSGSIZE;
934 break;
1ab1457c 935
1da177e4
LT
936 case ICMPV6_PARAMPROB:
937 *err = EPROTO;
938 fatal = 1;
939 break;
940
941 case ICMPV6_TIME_EXCEED:
942 *err = EHOSTUNREACH;
943 break;
3ff50b79 944 }
1da177e4
LT
945
946 return fatal;
947}
948
7159039a
YH
949EXPORT_SYMBOL(icmpv6_err_convert);
950
1da177e4 951#ifdef CONFIG_SYSCTL
760f2d01 952ctl_table ipv6_icmp_table_template[] = {
1da177e4
LT
953 {
954 .ctl_name = NET_IPV6_ICMP_RATELIMIT,
955 .procname = "ratelimit",
41a76906 956 .data = &init_net.ipv6.sysctl.icmpv6_time,
1da177e4
LT
957 .maxlen = sizeof(int),
958 .mode = 0644,
6dbf4bca
SH
959 .proc_handler = &proc_dointvec_ms_jiffies,
960 .strategy = &sysctl_ms_jiffies
1da177e4
LT
961 },
962 { .ctl_name = 0 },
963};
760f2d01
DL
964
965struct ctl_table *ipv6_icmp_sysctl_init(struct net *net)
966{
967 struct ctl_table *table;
968
969 table = kmemdup(ipv6_icmp_table_template,
970 sizeof(ipv6_icmp_table_template),
971 GFP_KERNEL);
5ee09105
YH
972
973 if (table)
974 table[0].data = &net->ipv6.sysctl.icmpv6_time;
975
760f2d01
DL
976 return table;
977}
1da177e4
LT
978#endif
979