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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>
5a0e3ad6 43#include <linux/slab.h>
1da177e4
LT
44
45#ifdef CONFIG_SYSCTL
46#include <linux/sysctl.h>
47#endif
48
49#include <linux/inet.h>
50#include <linux/netdevice.h>
51#include <linux/icmpv6.h>
52
53#include <net/ip.h>
54#include <net/sock.h>
55
56#include <net/ipv6.h>
57#include <net/ip6_checksum.h>
58#include <net/protocol.h>
59#include <net/raw.h>
60#include <net/rawv6.h>
61#include <net/transp_v6.h>
62#include <net/ip6_route.h>
63#include <net/addrconf.h>
64#include <net/icmp.h>
8b7817f3 65#include <net/xfrm.h>
1ed8516f 66#include <net/inet_common.h>
1da177e4
LT
67
68#include <asm/uaccess.h>
69#include <asm/system.h>
70
1da177e4
LT
71/*
72 * The ICMP socket(s). This is the most convenient way to flow control
73 * our ICMP output as well as maintain a clean interface throughout
74 * all layers. All Socketless IP sends will soon be gone.
75 *
76 * On SMP we have one ICMP socket per-cpu.
77 */
98c6d1b2
DL
78static inline struct sock *icmpv6_sk(struct net *net)
79{
80 return net->ipv6.icmp_sk[smp_processor_id()];
81}
1da177e4 82
e5bbef20 83static int icmpv6_rcv(struct sk_buff *skb);
1da177e4 84
41135cc8 85static const struct inet6_protocol icmpv6_protocol = {
1da177e4 86 .handler = icmpv6_rcv,
8b7817f3 87 .flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
1da177e4
LT
88};
89
fdc0bde9 90static __inline__ struct sock *icmpv6_xmit_lock(struct net *net)
1da177e4 91{
fdc0bde9
DL
92 struct sock *sk;
93
1da177e4
LT
94 local_bh_disable();
95
fdc0bde9 96 sk = icmpv6_sk(net);
405666db 97 if (unlikely(!spin_trylock(&sk->sk_lock.slock))) {
1da177e4
LT
98 /* This can happen if the output path (f.e. SIT or
99 * ip6ip6 tunnel) signals dst_link_failure() for an
100 * outgoing ICMP6 packet.
101 */
102 local_bh_enable();
fdc0bde9 103 return NULL;
1da177e4 104 }
fdc0bde9 105 return sk;
1da177e4
LT
106}
107
405666db 108static __inline__ void icmpv6_xmit_unlock(struct sock *sk)
1da177e4 109{
405666db 110 spin_unlock_bh(&sk->sk_lock.slock);
1da177e4
LT
111}
112
1ab1457c 113/*
1da177e4
LT
114 * Slightly more convenient version of icmpv6_send.
115 */
d5fdd6ba 116void icmpv6_param_prob(struct sk_buff *skb, u8 code, int pos)
1da177e4 117{
3ffe533c 118 icmpv6_send(skb, ICMPV6_PARAMPROB, code, pos);
1da177e4
LT
119 kfree_skb(skb);
120}
121
122/*
123 * Figure out, may we reply to this packet with icmp error.
124 *
125 * We do not reply, if:
126 * - it was icmp error message.
127 * - it is truncated, so that it is known, that protocol is ICMPV6
128 * (i.e. in the middle of some exthdr)
129 *
130 * --ANK (980726)
131 */
132
133static int is_ineligible(struct sk_buff *skb)
134{
0660e03f 135 int ptr = (u8 *)(ipv6_hdr(skb) + 1) - skb->data;
1da177e4 136 int len = skb->len - ptr;
0660e03f 137 __u8 nexthdr = ipv6_hdr(skb)->nexthdr;
75f2811c 138 __be16 frag_off;
1da177e4
LT
139
140 if (len < 0)
141 return 1;
142
75f2811c 143 ptr = ipv6_skip_exthdr(skb, ptr, &nexthdr, &frag_off);
1da177e4
LT
144 if (ptr < 0)
145 return 0;
146 if (nexthdr == IPPROTO_ICMPV6) {
147 u8 _type, *tp;
148 tp = skb_header_pointer(skb,
149 ptr+offsetof(struct icmp6hdr, icmp6_type),
150 sizeof(_type), &_type);
151 if (tp == NULL ||
152 !(*tp & ICMPV6_INFOMSG_MASK))
153 return 1;
154 }
155 return 0;
156}
157
1ab1457c
YH
158/*
159 * Check the ICMP output rate limit
1da177e4 160 */
92d86829 161static inline bool icmpv6_xrlim_allow(struct sock *sk, u8 type,
4c9483b2 162 struct flowi6 *fl6)
1da177e4
LT
163{
164 struct dst_entry *dst;
3b1e0a65 165 struct net *net = sock_net(sk);
92d86829 166 bool res = false;
1da177e4
LT
167
168 /* Informational messages are not limited. */
169 if (type & ICMPV6_INFOMSG_MASK)
92d86829 170 return true;
1da177e4
LT
171
172 /* Do not limit pmtu discovery, it would break it. */
173 if (type == ICMPV6_PKT_TOOBIG)
92d86829 174 return true;
1da177e4 175
1ab1457c 176 /*
1da177e4
LT
177 * Look up the output route.
178 * XXX: perhaps the expire for routing entries cloned by
179 * this lookup should be more aggressive (not longer than timeout).
180 */
4c9483b2 181 dst = ip6_route_output(net, sk, fl6);
1da177e4 182 if (dst->error) {
3bd653c8 183 IP6_INC_STATS(net, ip6_dst_idev(dst),
a11d206d 184 IPSTATS_MIB_OUTNOROUTES);
1da177e4 185 } else if (dst->dev && (dst->dev->flags&IFF_LOOPBACK)) {
92d86829 186 res = true;
1da177e4
LT
187 } else {
188 struct rt6_info *rt = (struct rt6_info *)dst;
9a43b709 189 int tmo = net->ipv6.sysctl.icmpv6_time;
1da177e4
LT
190
191 /* Give more bandwidth to wider prefixes. */
192 if (rt->rt6i_dst.plen < 128)
193 tmo >>= ((128 - rt->rt6i_dst.plen)>>5);
194
92d86829
DM
195 if (!rt->rt6i_peer)
196 rt6_bind_peer(rt, 1);
197 res = inet_peer_xrlim_allow(rt->rt6i_peer, tmo);
1da177e4
LT
198 }
199 dst_release(dst);
200 return res;
201}
202
203/*
204 * an inline helper for the "simple" if statement below
205 * checks if parameter problem report is caused by an
1ab1457c 206 * unrecognized IPv6 option that has the Option Type
1da177e4
LT
207 * highest-order two bits set to 10
208 */
209
210static __inline__ int opt_unrec(struct sk_buff *skb, __u32 offset)
211{
212 u8 _optval, *op;
213
bbe735e4 214 offset += skb_network_offset(skb);
1da177e4
LT
215 op = skb_header_pointer(skb, offset, sizeof(_optval), &_optval);
216 if (op == NULL)
217 return 1;
218 return (*op & 0xC0) == 0x80;
219}
220
4c9483b2 221static int icmpv6_push_pending_frames(struct sock *sk, struct flowi6 *fl6, struct icmp6hdr *thdr, int len)
1da177e4
LT
222{
223 struct sk_buff *skb;
224 struct icmp6hdr *icmp6h;
225 int err = 0;
226
227 if ((skb = skb_peek(&sk->sk_write_queue)) == NULL)
228 goto out;
229
cc70ab26 230 icmp6h = icmp6_hdr(skb);
1da177e4
LT
231 memcpy(icmp6h, thdr, sizeof(struct icmp6hdr));
232 icmp6h->icmp6_cksum = 0;
233
234 if (skb_queue_len(&sk->sk_write_queue) == 1) {
07f0757a 235 skb->csum = csum_partial(icmp6h,
1da177e4 236 sizeof(struct icmp6hdr), skb->csum);
4c9483b2
DM
237 icmp6h->icmp6_cksum = csum_ipv6_magic(&fl6->saddr,
238 &fl6->daddr,
239 len, fl6->flowi6_proto,
1da177e4
LT
240 skb->csum);
241 } else {
868c86bc 242 __wsum tmp_csum = 0;
1da177e4
LT
243
244 skb_queue_walk(&sk->sk_write_queue, skb) {
245 tmp_csum = csum_add(tmp_csum, skb->csum);
246 }
247
07f0757a 248 tmp_csum = csum_partial(icmp6h,
1da177e4 249 sizeof(struct icmp6hdr), tmp_csum);
4c9483b2
DM
250 icmp6h->icmp6_cksum = csum_ipv6_magic(&fl6->saddr,
251 &fl6->daddr,
252 len, fl6->flowi6_proto,
868c86bc 253 tmp_csum);
1da177e4 254 }
1da177e4
LT
255 ip6_push_pending_frames(sk);
256out:
257 return err;
258}
259
260struct icmpv6_msg {
261 struct sk_buff *skb;
262 int offset;
763ecff1 263 uint8_t type;
1da177e4
LT
264};
265
266static int icmpv6_getfrag(void *from, char *to, int offset, int len, int odd, struct sk_buff *skb)
267{
268 struct icmpv6_msg *msg = (struct icmpv6_msg *) from;
269 struct sk_buff *org_skb = msg->skb;
5f92a738 270 __wsum csum = 0;
1da177e4
LT
271
272 csum = skb_copy_and_csum_bits(org_skb, msg->offset + offset,
273 to, len, csum);
274 skb->csum = csum_block_add(skb->csum, csum, odd);
763ecff1
YK
275 if (!(msg->type & ICMPV6_INFOMSG_MASK))
276 nf_ct_attach(skb, org_skb);
1da177e4
LT
277 return 0;
278}
279
59fbb3a6 280#if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
79383236
MN
281static void mip6_addr_swap(struct sk_buff *skb)
282{
0660e03f 283 struct ipv6hdr *iph = ipv6_hdr(skb);
79383236
MN
284 struct inet6_skb_parm *opt = IP6CB(skb);
285 struct ipv6_destopt_hao *hao;
286 struct in6_addr tmp;
287 int off;
288
289 if (opt->dsthao) {
290 off = ipv6_find_tlv(skb, opt->dsthao, IPV6_TLV_HAO);
291 if (likely(off >= 0)) {
d56f90a7
ACM
292 hao = (struct ipv6_destopt_hao *)
293 (skb_network_header(skb) + off);
4e3fd7a0
AD
294 tmp = iph->saddr;
295 iph->saddr = hao->addr;
296 hao->addr = tmp;
79383236
MN
297 }
298 }
299}
300#else
301static inline void mip6_addr_swap(struct sk_buff *skb) {}
302#endif
303
b42835db 304static struct dst_entry *icmpv6_route_lookup(struct net *net, struct sk_buff *skb,
4c9483b2 305 struct sock *sk, struct flowi6 *fl6)
b42835db
DM
306{
307 struct dst_entry *dst, *dst2;
4c9483b2 308 struct flowi6 fl2;
b42835db
DM
309 int err;
310
4c9483b2 311 err = ip6_dst_lookup(sk, &dst, fl6);
b42835db
DM
312 if (err)
313 return ERR_PTR(err);
314
315 /*
316 * We won't send icmp if the destination is known
317 * anycast.
318 */
319 if (((struct rt6_info *)dst)->rt6i_flags & RTF_ANYCAST) {
320 LIMIT_NETDEBUG(KERN_DEBUG "icmpv6_send: acast source\n");
321 dst_release(dst);
322 return ERR_PTR(-EINVAL);
323 }
324
325 /* No need to clone since we're just using its address. */
326 dst2 = dst;
327
4c9483b2 328 dst = xfrm_lookup(net, dst, flowi6_to_flowi(fl6), sk, 0);
452edd59 329 if (!IS_ERR(dst)) {
b42835db
DM
330 if (dst != dst2)
331 return dst;
452edd59
DM
332 } else {
333 if (PTR_ERR(dst) == -EPERM)
334 dst = NULL;
335 else
336 return dst;
b42835db
DM
337 }
338
4c9483b2 339 err = xfrm_decode_session_reverse(skb, flowi6_to_flowi(&fl2), AF_INET6);
b42835db
DM
340 if (err)
341 goto relookup_failed;
342
343 err = ip6_dst_lookup(sk, &dst2, &fl2);
344 if (err)
345 goto relookup_failed;
346
4c9483b2 347 dst2 = xfrm_lookup(net, dst2, flowi6_to_flowi(&fl2), sk, XFRM_LOOKUP_ICMP);
452edd59 348 if (!IS_ERR(dst2)) {
b42835db
DM
349 dst_release(dst);
350 dst = dst2;
452edd59
DM
351 } else {
352 err = PTR_ERR(dst2);
353 if (err == -EPERM) {
354 dst_release(dst);
355 return dst2;
356 } else
357 goto relookup_failed;
b42835db
DM
358 }
359
360relookup_failed:
361 if (dst)
362 return dst;
363 return ERR_PTR(err);
364}
365
1da177e4
LT
366/*
367 * Send an ICMP message in response to a packet in error
368 */
3ffe533c 369void icmpv6_send(struct sk_buff *skb, u8 type, u8 code, __u32 info)
1da177e4 370{
c346dca1 371 struct net *net = dev_net(skb->dev);
1da177e4 372 struct inet6_dev *idev = NULL;
0660e03f 373 struct ipv6hdr *hdr = ipv6_hdr(skb);
84427d53
YH
374 struct sock *sk;
375 struct ipv6_pinfo *np;
b71d1d42 376 const struct in6_addr *saddr = NULL;
1da177e4
LT
377 struct dst_entry *dst;
378 struct icmp6hdr tmp_hdr;
4c9483b2 379 struct flowi6 fl6;
1da177e4
LT
380 struct icmpv6_msg msg;
381 int iif = 0;
382 int addr_type = 0;
383 int len;
e651f03a 384 int hlimit;
1da177e4
LT
385 int err = 0;
386
27a884dc
ACM
387 if ((u8 *)hdr < skb->head ||
388 (skb->network_header + sizeof(*hdr)) > skb->tail)
1da177e4
LT
389 return;
390
391 /*
1ab1457c 392 * Make sure we respect the rules
1da177e4
LT
393 * i.e. RFC 1885 2.4(e)
394 * Rule (e.1) is enforced by not using icmpv6_send
395 * in any code that processes icmp errors.
396 */
397 addr_type = ipv6_addr_type(&hdr->daddr);
398
9a43b709 399 if (ipv6_chk_addr(net, &hdr->daddr, skb->dev, 0))
1da177e4
LT
400 saddr = &hdr->daddr;
401
402 /*
403 * Dest addr check
404 */
405
406 if ((addr_type & IPV6_ADDR_MULTICAST || skb->pkt_type != PACKET_HOST)) {
407 if (type != ICMPV6_PKT_TOOBIG &&
1ab1457c
YH
408 !(type == ICMPV6_PARAMPROB &&
409 code == ICMPV6_UNK_OPTION &&
1da177e4
LT
410 (opt_unrec(skb, info))))
411 return;
412
413 saddr = NULL;
414 }
415
416 addr_type = ipv6_addr_type(&hdr->saddr);
417
418 /*
419 * Source addr check
420 */
421
422 if (addr_type & IPV6_ADDR_LINKLOCAL)
423 iif = skb->dev->ifindex;
424
425 /*
8de3351e
YH
426 * Must not send error if the source does not uniquely
427 * identify a single node (RFC2463 Section 2.4).
428 * We check unspecified / multicast addresses here,
429 * and anycast addresses will be checked later.
1da177e4
LT
430 */
431 if ((addr_type == IPV6_ADDR_ANY) || (addr_type & IPV6_ADDR_MULTICAST)) {
64ce2073 432 LIMIT_NETDEBUG(KERN_DEBUG "icmpv6_send: addr_any/mcast source\n");
1da177e4
LT
433 return;
434 }
435
1ab1457c 436 /*
1da177e4
LT
437 * Never answer to a ICMP packet.
438 */
439 if (is_ineligible(skb)) {
64ce2073 440 LIMIT_NETDEBUG(KERN_DEBUG "icmpv6_send: no reply to icmp error\n");
1da177e4
LT
441 return;
442 }
443
79383236
MN
444 mip6_addr_swap(skb);
445
4c9483b2
DM
446 memset(&fl6, 0, sizeof(fl6));
447 fl6.flowi6_proto = IPPROTO_ICMPV6;
4e3fd7a0 448 fl6.daddr = hdr->saddr;
1da177e4 449 if (saddr)
4e3fd7a0 450 fl6.saddr = *saddr;
4c9483b2 451 fl6.flowi6_oif = iif;
1958b856
DM
452 fl6.fl6_icmp_type = type;
453 fl6.fl6_icmp_code = code;
4c9483b2 454 security_skb_classify_flow(skb, flowi6_to_flowi(&fl6));
1da177e4 455
fdc0bde9
DL
456 sk = icmpv6_xmit_lock(net);
457 if (sk == NULL)
405666db 458 return;
fdc0bde9 459 np = inet6_sk(sk);
405666db 460
4c9483b2 461 if (!icmpv6_xrlim_allow(sk, type, &fl6))
1da177e4
LT
462 goto out;
463
464 tmp_hdr.icmp6_type = type;
465 tmp_hdr.icmp6_code = code;
466 tmp_hdr.icmp6_cksum = 0;
467 tmp_hdr.icmp6_pointer = htonl(info);
468
4c9483b2
DM
469 if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr))
470 fl6.flowi6_oif = np->mcast_oif;
c4062dfc
EH
471 else if (!fl6.flowi6_oif)
472 fl6.flowi6_oif = np->ucast_oif;
1da177e4 473
4c9483b2 474 dst = icmpv6_route_lookup(net, skb, sk, &fl6);
b42835db 475 if (IS_ERR(dst))
1da177e4 476 goto out;
8de3351e 477
4c9483b2 478 if (ipv6_addr_is_multicast(&fl6.daddr))
1da177e4
LT
479 hlimit = np->mcast_hops;
480 else
481 hlimit = np->hop_limit;
482 if (hlimit < 0)
6b75d090 483 hlimit = ip6_dst_hoplimit(dst);
1da177e4
LT
484
485 msg.skb = skb;
bbe735e4 486 msg.offset = skb_network_offset(skb);
763ecff1 487 msg.type = type;
1da177e4
LT
488
489 len = skb->len - msg.offset;
490 len = min_t(unsigned int, len, IPV6_MIN_MTU - sizeof(struct ipv6hdr) -sizeof(struct icmp6hdr));
491 if (len < 0) {
64ce2073 492 LIMIT_NETDEBUG(KERN_DEBUG "icmp: len problem\n");
1da177e4
LT
493 goto out_dst_release;
494 }
495
cfdf7647
ED
496 rcu_read_lock();
497 idev = __in6_dev_get(skb->dev);
1da177e4
LT
498
499 err = ip6_append_data(sk, icmpv6_getfrag, &msg,
500 len + sizeof(struct icmp6hdr),
e651f03a 501 sizeof(struct icmp6hdr), hlimit,
4c9483b2 502 np->tclass, NULL, &fl6, (struct rt6_info*)dst,
13b52cd4 503 MSG_DONTWAIT, np->dontfrag);
1da177e4 504 if (err) {
00d9d6a1 505 ICMP6_INC_STATS_BH(net, idev, ICMP6_MIB_OUTERRORS);
1da177e4 506 ip6_flush_pending_frames(sk);
cfdf7647
ED
507 } else {
508 err = icmpv6_push_pending_frames(sk, &fl6, &tmp_hdr,
509 len + sizeof(struct icmp6hdr));
1da177e4 510 }
cfdf7647 511 rcu_read_unlock();
1da177e4
LT
512out_dst_release:
513 dst_release(dst);
514out:
405666db 515 icmpv6_xmit_unlock(sk);
1da177e4 516}
7159039a
YH
517EXPORT_SYMBOL(icmpv6_send);
518
1da177e4
LT
519static void icmpv6_echo_reply(struct sk_buff *skb)
520{
c346dca1 521 struct net *net = dev_net(skb->dev);
84427d53 522 struct sock *sk;
1da177e4 523 struct inet6_dev *idev;
84427d53 524 struct ipv6_pinfo *np;
b71d1d42 525 const struct in6_addr *saddr = NULL;
cc70ab26 526 struct icmp6hdr *icmph = icmp6_hdr(skb);
1da177e4 527 struct icmp6hdr tmp_hdr;
4c9483b2 528 struct flowi6 fl6;
1da177e4
LT
529 struct icmpv6_msg msg;
530 struct dst_entry *dst;
531 int err = 0;
532 int hlimit;
533
0660e03f 534 saddr = &ipv6_hdr(skb)->daddr;
1da177e4
LT
535
536 if (!ipv6_unicast_destination(skb))
537 saddr = NULL;
538
539 memcpy(&tmp_hdr, icmph, sizeof(tmp_hdr));
540 tmp_hdr.icmp6_type = ICMPV6_ECHO_REPLY;
541
4c9483b2
DM
542 memset(&fl6, 0, sizeof(fl6));
543 fl6.flowi6_proto = IPPROTO_ICMPV6;
4e3fd7a0 544 fl6.daddr = ipv6_hdr(skb)->saddr;
1da177e4 545 if (saddr)
4e3fd7a0 546 fl6.saddr = *saddr;
4c9483b2 547 fl6.flowi6_oif = skb->dev->ifindex;
1958b856 548 fl6.fl6_icmp_type = ICMPV6_ECHO_REPLY;
4c9483b2 549 security_skb_classify_flow(skb, flowi6_to_flowi(&fl6));
1da177e4 550
fdc0bde9
DL
551 sk = icmpv6_xmit_lock(net);
552 if (sk == NULL)
405666db 553 return;
fdc0bde9 554 np = inet6_sk(sk);
405666db 555
4c9483b2
DM
556 if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr))
557 fl6.flowi6_oif = np->mcast_oif;
c4062dfc
EH
558 else if (!fl6.flowi6_oif)
559 fl6.flowi6_oif = np->ucast_oif;
1da177e4 560
4c9483b2 561 err = ip6_dst_lookup(sk, &dst, &fl6);
1da177e4
LT
562 if (err)
563 goto out;
4c9483b2 564 dst = xfrm_lookup(net, dst, flowi6_to_flowi(&fl6), sk, 0);
452edd59 565 if (IS_ERR(dst))
e104411b 566 goto out;
1da177e4 567
4c9483b2 568 if (ipv6_addr_is_multicast(&fl6.daddr))
1da177e4
LT
569 hlimit = np->mcast_hops;
570 else
571 hlimit = np->hop_limit;
572 if (hlimit < 0)
6b75d090 573 hlimit = ip6_dst_hoplimit(dst);
1da177e4 574
cfdf7647 575 idev = __in6_dev_get(skb->dev);
1da177e4
LT
576
577 msg.skb = skb;
578 msg.offset = 0;
763ecff1 579 msg.type = ICMPV6_ECHO_REPLY;
1da177e4
LT
580
581 err = ip6_append_data(sk, icmpv6_getfrag, &msg, skb->len + sizeof(struct icmp6hdr),
4c9483b2 582 sizeof(struct icmp6hdr), hlimit, np->tclass, NULL, &fl6,
13b52cd4
BH
583 (struct rt6_info*)dst, MSG_DONTWAIT,
584 np->dontfrag);
1da177e4
LT
585
586 if (err) {
00d9d6a1 587 ICMP6_INC_STATS_BH(net, idev, ICMP6_MIB_OUTERRORS);
1da177e4 588 ip6_flush_pending_frames(sk);
cfdf7647
ED
589 } else {
590 err = icmpv6_push_pending_frames(sk, &fl6, &tmp_hdr,
591 skb->len + sizeof(struct icmp6hdr));
1da177e4 592 }
1da177e4 593 dst_release(dst);
1ab1457c 594out:
405666db 595 icmpv6_xmit_unlock(sk);
1da177e4
LT
596}
597
d5fdd6ba 598static void icmpv6_notify(struct sk_buff *skb, u8 type, u8 code, __be32 info)
1da177e4 599{
41135cc8 600 const struct inet6_protocol *ipprot;
1da177e4
LT
601 int inner_offset;
602 int hash;
603 u8 nexthdr;
75f2811c 604 __be16 frag_off;
1da177e4
LT
605
606 if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
607 return;
608
609 nexthdr = ((struct ipv6hdr *)skb->data)->nexthdr;
610 if (ipv6_ext_hdr(nexthdr)) {
611 /* now skip over extension headers */
75f2811c
JG
612 inner_offset = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr),
613 &nexthdr, &frag_off);
1da177e4
LT
614 if (inner_offset<0)
615 return;
616 } else {
617 inner_offset = sizeof(struct ipv6hdr);
618 }
619
620 /* Checkin header including 8 bytes of inner protocol header. */
621 if (!pskb_may_pull(skb, inner_offset+8))
622 return;
623
1da177e4
LT
624 /* BUGGG_FUTURE: we should try to parse exthdrs in this packet.
625 Without this we will not able f.e. to make source routed
626 pmtu discovery.
627 Corresponding argument (opt) to notifiers is already added.
628 --ANK (980726)
629 */
630
631 hash = nexthdr & (MAX_INET_PROTOS - 1);
632
633 rcu_read_lock();
634 ipprot = rcu_dereference(inet6_protos[hash]);
635 if (ipprot && ipprot->err_handler)
636 ipprot->err_handler(skb, NULL, type, code, inner_offset, info);
637 rcu_read_unlock();
638
69d6da0b 639 raw6_icmp_error(skb, nexthdr, type, code, inner_offset, info);
1da177e4 640}
1ab1457c 641
1da177e4
LT
642/*
643 * Handle icmp messages
644 */
645
e5bbef20 646static int icmpv6_rcv(struct sk_buff *skb)
1da177e4 647{
1da177e4
LT
648 struct net_device *dev = skb->dev;
649 struct inet6_dev *idev = __in6_dev_get(dev);
b71d1d42
ED
650 const struct in6_addr *saddr, *daddr;
651 const struct ipv6hdr *orig_hdr;
1da177e4 652 struct icmp6hdr *hdr;
d5fdd6ba 653 u8 type;
1da177e4 654
aebcf82c 655 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) {
def8b4fa 656 struct sec_path *sp = skb_sec_path(skb);
8b7817f3
HX
657 int nh;
658
def8b4fa 659 if (!(sp && sp->xvec[sp->len - 1]->props.flags &
aebcf82c
HX
660 XFRM_STATE_ICMP))
661 goto drop_no_count;
662
8b7817f3
HX
663 if (!pskb_may_pull(skb, sizeof(*hdr) + sizeof(*orig_hdr)))
664 goto drop_no_count;
665
666 nh = skb_network_offset(skb);
667 skb_set_network_header(skb, sizeof(*hdr));
668
669 if (!xfrm6_policy_check_reverse(NULL, XFRM_POLICY_IN, skb))
670 goto drop_no_count;
671
672 skb_set_network_header(skb, nh);
673 }
674
e41b5368 675 ICMP6_INC_STATS_BH(dev_net(dev), idev, ICMP6_MIB_INMSGS);
1da177e4 676
0660e03f
ACM
677 saddr = &ipv6_hdr(skb)->saddr;
678 daddr = &ipv6_hdr(skb)->daddr;
1da177e4
LT
679
680 /* Perform checksum. */
fb286bb2 681 switch (skb->ip_summed) {
84fa7933 682 case CHECKSUM_COMPLETE:
fb286bb2
HX
683 if (!csum_ipv6_magic(saddr, daddr, skb->len, IPPROTO_ICMPV6,
684 skb->csum))
685 break;
686 /* fall through */
687 case CHECKSUM_NONE:
868c86bc
AV
688 skb->csum = ~csum_unfold(csum_ipv6_magic(saddr, daddr, skb->len,
689 IPPROTO_ICMPV6, 0));
fb286bb2 690 if (__skb_checksum_complete(skb)) {
5b095d98 691 LIMIT_NETDEBUG(KERN_DEBUG "ICMPv6 checksum failed [%pI6 > %pI6]\n",
0c6ce78a 692 saddr, daddr);
1da177e4
LT
693 goto discard_it;
694 }
695 }
696
8cf22943
HX
697 if (!pskb_pull(skb, sizeof(*hdr)))
698 goto discard_it;
1da177e4 699
cc70ab26 700 hdr = icmp6_hdr(skb);
1da177e4
LT
701
702 type = hdr->icmp6_type;
703
55d43808 704 ICMP6MSGIN_INC_STATS_BH(dev_net(dev), idev, type);
1da177e4
LT
705
706 switch (type) {
707 case ICMPV6_ECHO_REQUEST:
708 icmpv6_echo_reply(skb);
709 break;
710
711 case ICMPV6_ECHO_REPLY:
712 /* we couldn't care less */
713 break;
714
715 case ICMPV6_PKT_TOOBIG:
716 /* BUGGG_FUTURE: if packet contains rthdr, we cannot update
717 standard destination cache. Seems, only "advanced"
718 destination cache will allow to solve this problem
719 --ANK (980726)
720 */
721 if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
722 goto discard_it;
cc70ab26 723 hdr = icmp6_hdr(skb);
1da177e4
LT
724 orig_hdr = (struct ipv6hdr *) (hdr + 1);
725 rt6_pmtu_discovery(&orig_hdr->daddr, &orig_hdr->saddr, dev,
726 ntohl(hdr->icmp6_mtu));
727
728 /*
729 * Drop through to notify
730 */
731
732 case ICMPV6_DEST_UNREACH:
733 case ICMPV6_TIME_EXCEED:
734 case ICMPV6_PARAMPROB:
735 icmpv6_notify(skb, type, hdr->icmp6_code, hdr->icmp6_mtu);
736 break;
737
738 case NDISC_ROUTER_SOLICITATION:
739 case NDISC_ROUTER_ADVERTISEMENT:
740 case NDISC_NEIGHBOUR_SOLICITATION:
741 case NDISC_NEIGHBOUR_ADVERTISEMENT:
742 case NDISC_REDIRECT:
743 ndisc_rcv(skb);
744 break;
745
746 case ICMPV6_MGM_QUERY:
747 igmp6_event_query(skb);
748 break;
749
750 case ICMPV6_MGM_REPORT:
751 igmp6_event_report(skb);
752 break;
753
754 case ICMPV6_MGM_REDUCTION:
755 case ICMPV6_NI_QUERY:
756 case ICMPV6_NI_REPLY:
757 case ICMPV6_MLD2_REPORT:
758 case ICMPV6_DHAAD_REQUEST:
759 case ICMPV6_DHAAD_REPLY:
760 case ICMPV6_MOBILE_PREFIX_SOL:
761 case ICMPV6_MOBILE_PREFIX_ADV:
762 break;
763
764 default:
64ce2073 765 LIMIT_NETDEBUG(KERN_DEBUG "icmpv6: msg of unknown type\n");
1da177e4
LT
766
767 /* informational */
768 if (type & ICMPV6_INFOMSG_MASK)
769 break;
770
1ab1457c
YH
771 /*
772 * error of unknown type.
773 * must pass to upper level
1da177e4
LT
774 */
775
776 icmpv6_notify(skb, type, hdr->icmp6_code, hdr->icmp6_mtu);
3ff50b79
SH
777 }
778
1da177e4
LT
779 kfree_skb(skb);
780 return 0;
781
782discard_it:
e41b5368 783 ICMP6_INC_STATS_BH(dev_net(dev), idev, ICMP6_MIB_INERRORS);
8b7817f3 784drop_no_count:
1da177e4
LT
785 kfree_skb(skb);
786 return 0;
787}
788
4c9483b2 789void icmpv6_flow_init(struct sock *sk, struct flowi6 *fl6,
95e41e93
YH
790 u8 type,
791 const struct in6_addr *saddr,
792 const struct in6_addr *daddr,
793 int oif)
794{
4c9483b2 795 memset(fl6, 0, sizeof(*fl6));
4e3fd7a0
AD
796 fl6->saddr = *saddr;
797 fl6->daddr = *daddr;
4c9483b2 798 fl6->flowi6_proto = IPPROTO_ICMPV6;
1958b856
DM
799 fl6->fl6_icmp_type = type;
800 fl6->fl6_icmp_code = 0;
4c9483b2
DM
801 fl6->flowi6_oif = oif;
802 security_sk_classify_flow(sk, flowi6_to_flowi(fl6));
95e41e93
YH
803}
804
640c41c7 805/*
b7e729c4 806 * Special lock-class for __icmpv6_sk:
640c41c7
IM
807 */
808static struct lock_class_key icmpv6_socket_sk_dst_lock_key;
809
98c6d1b2 810static int __net_init icmpv6_sk_init(struct net *net)
1da177e4
LT
811{
812 struct sock *sk;
813 int err, i, j;
814
98c6d1b2
DL
815 net->ipv6.icmp_sk =
816 kzalloc(nr_cpu_ids * sizeof(struct sock *), GFP_KERNEL);
817 if (net->ipv6.icmp_sk == NULL)
79c91159
DL
818 return -ENOMEM;
819
6f912042 820 for_each_possible_cpu(i) {
1ed8516f
DL
821 err = inet_ctl_sock_create(&sk, PF_INET6,
822 SOCK_RAW, IPPROTO_ICMPV6, net);
1da177e4
LT
823 if (err < 0) {
824 printk(KERN_ERR
825 "Failed to initialize the ICMP6 control socket "
826 "(err %d).\n",
827 err);
828 goto fail;
829 }
830
1ed8516f 831 net->ipv6.icmp_sk[i] = sk;
5c8cafd6 832
640c41c7
IM
833 /*
834 * Split off their lock-class, because sk->sk_dst_lock
835 * gets used from softirqs, which is safe for
b7e729c4 836 * __icmpv6_sk (because those never get directly used
640c41c7
IM
837 * via userspace syscalls), but unsafe for normal sockets.
838 */
839 lockdep_set_class(&sk->sk_dst_lock,
840 &icmpv6_socket_sk_dst_lock_key);
1da177e4
LT
841
842 /* Enough space for 2 64K ICMP packets, including
843 * sk_buff struct overhead.
844 */
87fb4b7b 845 sk->sk_sndbuf = 2 * SKB_TRUESIZE(64 * 1024);
1da177e4 846 }
1da177e4
LT
847 return 0;
848
849 fail:
5c8cafd6 850 for (j = 0; j < i; j++)
1ed8516f 851 inet_ctl_sock_destroy(net->ipv6.icmp_sk[j]);
98c6d1b2 852 kfree(net->ipv6.icmp_sk);
1da177e4
LT
853 return err;
854}
855
98c6d1b2 856static void __net_exit icmpv6_sk_exit(struct net *net)
1da177e4
LT
857{
858 int i;
859
6f912042 860 for_each_possible_cpu(i) {
1ed8516f 861 inet_ctl_sock_destroy(net->ipv6.icmp_sk[i]);
1da177e4 862 }
98c6d1b2
DL
863 kfree(net->ipv6.icmp_sk);
864}
865
8ed7edce 866static struct pernet_operations icmpv6_sk_ops = {
98c6d1b2
DL
867 .init = icmpv6_sk_init,
868 .exit = icmpv6_sk_exit,
869};
870
871int __init icmpv6_init(void)
872{
873 int err;
874
875 err = register_pernet_subsys(&icmpv6_sk_ops);
876 if (err < 0)
877 return err;
878
879 err = -EAGAIN;
880 if (inet6_add_protocol(&icmpv6_protocol, IPPROTO_ICMPV6) < 0)
881 goto fail;
882 return 0;
883
884fail:
885 printk(KERN_ERR "Failed to register ICMP6 protocol\n");
886 unregister_pernet_subsys(&icmpv6_sk_ops);
887 return err;
888}
889
8ed7edce 890void icmpv6_cleanup(void)
98c6d1b2
DL
891{
892 unregister_pernet_subsys(&icmpv6_sk_ops);
1da177e4
LT
893 inet6_del_protocol(&icmpv6_protocol, IPPROTO_ICMPV6);
894}
895
98c6d1b2 896
9b5b5cff 897static const struct icmp6_err {
1da177e4
LT
898 int err;
899 int fatal;
900} tab_unreach[] = {
901 { /* NOROUTE */
902 .err = ENETUNREACH,
903 .fatal = 0,
904 },
905 { /* ADM_PROHIBITED */
906 .err = EACCES,
907 .fatal = 1,
908 },
909 { /* Was NOT_NEIGHBOUR, now reserved */
910 .err = EHOSTUNREACH,
911 .fatal = 0,
912 },
913 { /* ADDR_UNREACH */
914 .err = EHOSTUNREACH,
915 .fatal = 0,
916 },
917 { /* PORT_UNREACH */
918 .err = ECONNREFUSED,
919 .fatal = 1,
920 },
921};
922
d5fdd6ba 923int icmpv6_err_convert(u8 type, u8 code, int *err)
1da177e4
LT
924{
925 int fatal = 0;
926
927 *err = EPROTO;
928
929 switch (type) {
930 case ICMPV6_DEST_UNREACH:
931 fatal = 1;
932 if (code <= ICMPV6_PORT_UNREACH) {
933 *err = tab_unreach[code].err;
934 fatal = tab_unreach[code].fatal;
935 }
936 break;
937
938 case ICMPV6_PKT_TOOBIG:
939 *err = EMSGSIZE;
940 break;
1ab1457c 941
1da177e4
LT
942 case ICMPV6_PARAMPROB:
943 *err = EPROTO;
944 fatal = 1;
945 break;
946
947 case ICMPV6_TIME_EXCEED:
948 *err = EHOSTUNREACH;
949 break;
3ff50b79 950 }
1da177e4
LT
951
952 return fatal;
953}
954
7159039a
YH
955EXPORT_SYMBOL(icmpv6_err_convert);
956
1da177e4 957#ifdef CONFIG_SYSCTL
760f2d01 958ctl_table ipv6_icmp_table_template[] = {
1da177e4 959 {
1da177e4 960 .procname = "ratelimit",
41a76906 961 .data = &init_net.ipv6.sysctl.icmpv6_time,
1da177e4
LT
962 .maxlen = sizeof(int),
963 .mode = 0644,
6d9f239a 964 .proc_handler = proc_dointvec_ms_jiffies,
1da177e4 965 },
f8572d8f 966 { },
1da177e4 967};
760f2d01 968
2c8c1e72 969struct ctl_table * __net_init ipv6_icmp_sysctl_init(struct net *net)
760f2d01
DL
970{
971 struct ctl_table *table;
972
973 table = kmemdup(ipv6_icmp_table_template,
974 sizeof(ipv6_icmp_table_template),
975 GFP_KERNEL);
5ee09105
YH
976
977 if (table)
978 table[0].data = &net->ipv6.sysctl.icmpv6_time;
979
760f2d01
DL
980 return table;
981}
1da177e4
LT
982#endif
983