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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Internet Control Message Protocol (ICMPv6)
4 * Linux INET6 implementation
5 *
6 * Authors:
7 * Pedro Roque <roque@di.fc.ul.pt>
8 *
9 * Based on net/ipv4/icmp.c
10 *
11 * RFC 1885
12 */
13
14/*
15 * Changes:
16 *
17 * Andi Kleen : exception handling
18 * Andi Kleen add rate limits. never reply to a icmp.
19 * add more length checks and other fixes.
20 * yoshfuji : ensure to sent parameter problem for
21 * fragments.
22 * YOSHIFUJI Hideaki @USAGI: added sysctl for icmp rate limit.
23 * Randy Dunlap and
24 * YOSHIFUJI Hideaki @USAGI: Per-interface statistics support
25 * Kazunori MIYAZAWA @USAGI: change output process to use ip6_append_data
26 */
27
28#define pr_fmt(fmt) "IPv6: " fmt
29
30#include <linux/module.h>
31#include <linux/errno.h>
32#include <linux/types.h>
33#include <linux/socket.h>
34#include <linux/in.h>
35#include <linux/kernel.h>
36#include <linux/sockios.h>
37#include <linux/net.h>
38#include <linux/skbuff.h>
39#include <linux/init.h>
40#include <linux/netfilter.h>
41#include <linux/slab.h>
42
43#ifdef CONFIG_SYSCTL
44#include <linux/sysctl.h>
45#endif
46
47#include <linux/inet.h>
48#include <linux/netdevice.h>
49#include <linux/icmpv6.h>
50
51#include <net/ip.h>
52#include <net/sock.h>
53
54#include <net/ipv6.h>
55#include <net/ip6_checksum.h>
56#include <net/ping.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>
64#include <net/xfrm.h>
65#include <net/inet_common.h>
66#include <net/dsfield.h>
67#include <net/l3mdev.h>
68
69#include <linux/uaccess.h>
70
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 */
78static struct sock *icmpv6_sk(struct net *net)
79{
80 return this_cpu_read(*net->ipv6.icmp_sk);
81}
82
83static int icmpv6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
84 u8 type, u8 code, int offset, __be32 info)
85{
86 /* icmpv6_notify checks 8 bytes can be pulled, icmp6hdr is 8 bytes */
87 struct icmp6hdr *icmp6 = (struct icmp6hdr *) (skb->data + offset);
88 struct net *net = dev_net(skb->dev);
89
90 if (type == ICMPV6_PKT_TOOBIG)
91 ip6_update_pmtu(skb, net, info, skb->dev->ifindex, 0, sock_net_uid(net, NULL));
92 else if (type == NDISC_REDIRECT)
93 ip6_redirect(skb, net, skb->dev->ifindex, 0,
94 sock_net_uid(net, NULL));
95
96 if (!(type & ICMPV6_INFOMSG_MASK))
97 if (icmp6->icmp6_type == ICMPV6_ECHO_REQUEST)
98 ping_err(skb, offset, ntohl(info));
99
100 return 0;
101}
102
103static int icmpv6_rcv(struct sk_buff *skb);
104
105static const struct inet6_protocol icmpv6_protocol = {
106 .handler = icmpv6_rcv,
107 .err_handler = icmpv6_err,
108 .flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
109};
110
111/* Called with BH disabled */
112static __inline__ struct sock *icmpv6_xmit_lock(struct net *net)
113{
114 struct sock *sk;
115
116 sk = icmpv6_sk(net);
117 if (unlikely(!spin_trylock(&sk->sk_lock.slock))) {
118 /* This can happen if the output path (f.e. SIT or
119 * ip6ip6 tunnel) signals dst_link_failure() for an
120 * outgoing ICMP6 packet.
121 */
122 return NULL;
123 }
124 return sk;
125}
126
127static __inline__ void icmpv6_xmit_unlock(struct sock *sk)
128{
129 spin_unlock(&sk->sk_lock.slock);
130}
131
132/*
133 * Figure out, may we reply to this packet with icmp error.
134 *
135 * We do not reply, if:
136 * - it was icmp error message.
137 * - it is truncated, so that it is known, that protocol is ICMPV6
138 * (i.e. in the middle of some exthdr)
139 *
140 * --ANK (980726)
141 */
142
143static bool is_ineligible(const struct sk_buff *skb)
144{
145 int ptr = (u8 *)(ipv6_hdr(skb) + 1) - skb->data;
146 int len = skb->len - ptr;
147 __u8 nexthdr = ipv6_hdr(skb)->nexthdr;
148 __be16 frag_off;
149
150 if (len < 0)
151 return true;
152
153 ptr = ipv6_skip_exthdr(skb, ptr, &nexthdr, &frag_off);
154 if (ptr < 0)
155 return false;
156 if (nexthdr == IPPROTO_ICMPV6) {
157 u8 _type, *tp;
158 tp = skb_header_pointer(skb,
159 ptr+offsetof(struct icmp6hdr, icmp6_type),
160 sizeof(_type), &_type);
161 if (!tp || !(*tp & ICMPV6_INFOMSG_MASK))
162 return true;
163 }
164 return false;
165}
166
167static bool icmpv6_mask_allow(struct net *net, int type)
168{
169 if (type > ICMPV6_MSG_MAX)
170 return true;
171
172 /* Limit if icmp type is set in ratemask. */
173 if (!test_bit(type, net->ipv6.sysctl.icmpv6_ratemask))
174 return true;
175
176 return false;
177}
178
179static bool icmpv6_global_allow(struct net *net, int type)
180{
181 if (icmpv6_mask_allow(net, type))
182 return true;
183
184 if (icmp_global_allow())
185 return true;
186
187 return false;
188}
189
190/*
191 * Check the ICMP output rate limit
192 */
193static bool icmpv6_xrlim_allow(struct sock *sk, u8 type,
194 struct flowi6 *fl6)
195{
196 struct net *net = sock_net(sk);
197 struct dst_entry *dst;
198 bool res = false;
199
200 if (icmpv6_mask_allow(net, type))
201 return true;
202
203 /*
204 * Look up the output route.
205 * XXX: perhaps the expire for routing entries cloned by
206 * this lookup should be more aggressive (not longer than timeout).
207 */
208 dst = ip6_route_output(net, sk, fl6);
209 if (dst->error) {
210 IP6_INC_STATS(net, ip6_dst_idev(dst),
211 IPSTATS_MIB_OUTNOROUTES);
212 } else if (dst->dev && (dst->dev->flags&IFF_LOOPBACK)) {
213 res = true;
214 } else {
215 struct rt6_info *rt = (struct rt6_info *)dst;
216 int tmo = net->ipv6.sysctl.icmpv6_time;
217 struct inet_peer *peer;
218
219 /* Give more bandwidth to wider prefixes. */
220 if (rt->rt6i_dst.plen < 128)
221 tmo >>= ((128 - rt->rt6i_dst.plen)>>5);
222
223 peer = inet_getpeer_v6(net->ipv6.peers, &fl6->daddr, 1);
224 res = inet_peer_xrlim_allow(peer, tmo);
225 if (peer)
226 inet_putpeer(peer);
227 }
228 dst_release(dst);
229 return res;
230}
231
232static bool icmpv6_rt_has_prefsrc(struct sock *sk, u8 type,
233 struct flowi6 *fl6)
234{
235 struct net *net = sock_net(sk);
236 struct dst_entry *dst;
237 bool res = false;
238
239 dst = ip6_route_output(net, sk, fl6);
240 if (!dst->error) {
241 struct rt6_info *rt = (struct rt6_info *)dst;
242 struct in6_addr prefsrc;
243
244 rt6_get_prefsrc(rt, &prefsrc);
245 res = !ipv6_addr_any(&prefsrc);
246 }
247 dst_release(dst);
248 return res;
249}
250
251/*
252 * an inline helper for the "simple" if statement below
253 * checks if parameter problem report is caused by an
254 * unrecognized IPv6 option that has the Option Type
255 * highest-order two bits set to 10
256 */
257
258static bool opt_unrec(struct sk_buff *skb, __u32 offset)
259{
260 u8 _optval, *op;
261
262 offset += skb_network_offset(skb);
263 op = skb_header_pointer(skb, offset, sizeof(_optval), &_optval);
264 if (!op)
265 return true;
266 return (*op & 0xC0) == 0x80;
267}
268
269void icmpv6_push_pending_frames(struct sock *sk, struct flowi6 *fl6,
270 struct icmp6hdr *thdr, int len)
271{
272 struct sk_buff *skb;
273 struct icmp6hdr *icmp6h;
274
275 skb = skb_peek(&sk->sk_write_queue);
276 if (!skb)
277 return;
278
279 icmp6h = icmp6_hdr(skb);
280 memcpy(icmp6h, thdr, sizeof(struct icmp6hdr));
281 icmp6h->icmp6_cksum = 0;
282
283 if (skb_queue_len(&sk->sk_write_queue) == 1) {
284 skb->csum = csum_partial(icmp6h,
285 sizeof(struct icmp6hdr), skb->csum);
286 icmp6h->icmp6_cksum = csum_ipv6_magic(&fl6->saddr,
287 &fl6->daddr,
288 len, fl6->flowi6_proto,
289 skb->csum);
290 } else {
291 __wsum tmp_csum = 0;
292
293 skb_queue_walk(&sk->sk_write_queue, skb) {
294 tmp_csum = csum_add(tmp_csum, skb->csum);
295 }
296
297 tmp_csum = csum_partial(icmp6h,
298 sizeof(struct icmp6hdr), tmp_csum);
299 icmp6h->icmp6_cksum = csum_ipv6_magic(&fl6->saddr,
300 &fl6->daddr,
301 len, fl6->flowi6_proto,
302 tmp_csum);
303 }
304 ip6_push_pending_frames(sk);
305}
306
307struct icmpv6_msg {
308 struct sk_buff *skb;
309 int offset;
310 uint8_t type;
311};
312
313static int icmpv6_getfrag(void *from, char *to, int offset, int len, int odd, struct sk_buff *skb)
314{
315 struct icmpv6_msg *msg = (struct icmpv6_msg *) from;
316 struct sk_buff *org_skb = msg->skb;
317 __wsum csum = 0;
318
319 csum = skb_copy_and_csum_bits(org_skb, msg->offset + offset,
320 to, len, csum);
321 skb->csum = csum_block_add(skb->csum, csum, odd);
322 if (!(msg->type & ICMPV6_INFOMSG_MASK))
323 nf_ct_attach(skb, org_skb);
324 return 0;
325}
326
327#if IS_ENABLED(CONFIG_IPV6_MIP6)
328static void mip6_addr_swap(struct sk_buff *skb)
329{
330 struct ipv6hdr *iph = ipv6_hdr(skb);
331 struct inet6_skb_parm *opt = IP6CB(skb);
332 struct ipv6_destopt_hao *hao;
333 struct in6_addr tmp;
334 int off;
335
336 if (opt->dsthao) {
337 off = ipv6_find_tlv(skb, opt->dsthao, IPV6_TLV_HAO);
338 if (likely(off >= 0)) {
339 hao = (struct ipv6_destopt_hao *)
340 (skb_network_header(skb) + off);
341 tmp = iph->saddr;
342 iph->saddr = hao->addr;
343 hao->addr = tmp;
344 }
345 }
346}
347#else
348static inline void mip6_addr_swap(struct sk_buff *skb) {}
349#endif
350
351static struct dst_entry *icmpv6_route_lookup(struct net *net,
352 struct sk_buff *skb,
353 struct sock *sk,
354 struct flowi6 *fl6)
355{
356 struct dst_entry *dst, *dst2;
357 struct flowi6 fl2;
358 int err;
359
360 err = ip6_dst_lookup(net, sk, &dst, fl6);
361 if (err)
362 return ERR_PTR(err);
363
364 /*
365 * We won't send icmp if the destination is known
366 * anycast.
367 */
368 if (ipv6_anycast_destination(dst, &fl6->daddr)) {
369 net_dbg_ratelimited("icmp6_send: acast source\n");
370 dst_release(dst);
371 return ERR_PTR(-EINVAL);
372 }
373
374 /* No need to clone since we're just using its address. */
375 dst2 = dst;
376
377 dst = xfrm_lookup(net, dst, flowi6_to_flowi(fl6), sk, 0);
378 if (!IS_ERR(dst)) {
379 if (dst != dst2)
380 return dst;
381 } else {
382 if (PTR_ERR(dst) == -EPERM)
383 dst = NULL;
384 else
385 return dst;
386 }
387
388 err = xfrm_decode_session_reverse(skb, flowi6_to_flowi(&fl2), AF_INET6);
389 if (err)
390 goto relookup_failed;
391
392 err = ip6_dst_lookup(net, sk, &dst2, &fl2);
393 if (err)
394 goto relookup_failed;
395
396 dst2 = xfrm_lookup(net, dst2, flowi6_to_flowi(&fl2), sk, XFRM_LOOKUP_ICMP);
397 if (!IS_ERR(dst2)) {
398 dst_release(dst);
399 dst = dst2;
400 } else {
401 err = PTR_ERR(dst2);
402 if (err == -EPERM) {
403 dst_release(dst);
404 return dst2;
405 } else
406 goto relookup_failed;
407 }
408
409relookup_failed:
410 if (dst)
411 return dst;
412 return ERR_PTR(err);
413}
414
415static struct net_device *icmp6_dev(const struct sk_buff *skb)
416{
417 struct net_device *dev = skb->dev;
418
419 /* for local traffic to local address, skb dev is the loopback
420 * device. Check if there is a dst attached to the skb and if so
421 * get the real device index. Same is needed for replies to a link
422 * local address on a device enslaved to an L3 master device
423 */
424 if (unlikely(dev->ifindex == LOOPBACK_IFINDEX || netif_is_l3_master(skb->dev))) {
425 const struct rt6_info *rt6 = skb_rt6_info(skb);
426
427 if (rt6)
428 dev = rt6->rt6i_idev->dev;
429 }
430
431 return dev;
432}
433
434static int icmp6_iif(const struct sk_buff *skb)
435{
436 return icmp6_dev(skb)->ifindex;
437}
438
439/*
440 * Send an ICMP message in response to a packet in error
441 */
442void icmp6_send(struct sk_buff *skb, u8 type, u8 code, __u32 info,
443 const struct in6_addr *force_saddr)
444{
445 struct inet6_dev *idev = NULL;
446 struct ipv6hdr *hdr = ipv6_hdr(skb);
447 struct sock *sk;
448 struct net *net;
449 struct ipv6_pinfo *np;
450 const struct in6_addr *saddr = NULL;
451 struct dst_entry *dst;
452 struct icmp6hdr tmp_hdr;
453 struct flowi6 fl6;
454 struct icmpv6_msg msg;
455 struct ipcm6_cookie ipc6;
456 int iif = 0;
457 int addr_type = 0;
458 int len;
459 u32 mark;
460
461 if ((u8 *)hdr < skb->head ||
462 (skb_network_header(skb) + sizeof(*hdr)) > skb_tail_pointer(skb))
463 return;
464
465 if (!skb->dev)
466 return;
467 net = dev_net(skb->dev);
468 mark = IP6_REPLY_MARK(net, skb->mark);
469 /*
470 * Make sure we respect the rules
471 * i.e. RFC 1885 2.4(e)
472 * Rule (e.1) is enforced by not using icmp6_send
473 * in any code that processes icmp errors.
474 */
475 addr_type = ipv6_addr_type(&hdr->daddr);
476
477 if (ipv6_chk_addr(net, &hdr->daddr, skb->dev, 0) ||
478 ipv6_chk_acast_addr_src(net, skb->dev, &hdr->daddr))
479 saddr = &hdr->daddr;
480
481 /*
482 * Dest addr check
483 */
484
485 if (addr_type & IPV6_ADDR_MULTICAST || skb->pkt_type != PACKET_HOST) {
486 if (type != ICMPV6_PKT_TOOBIG &&
487 !(type == ICMPV6_PARAMPROB &&
488 code == ICMPV6_UNK_OPTION &&
489 (opt_unrec(skb, info))))
490 return;
491
492 saddr = NULL;
493 }
494
495 addr_type = ipv6_addr_type(&hdr->saddr);
496
497 /*
498 * Source addr check
499 */
500
501 if (__ipv6_addr_needs_scope_id(addr_type)) {
502 iif = icmp6_iif(skb);
503 } else {
504 dst = skb_dst(skb);
505 iif = l3mdev_master_ifindex(dst ? dst->dev : skb->dev);
506 }
507
508 /*
509 * Must not send error if the source does not uniquely
510 * identify a single node (RFC2463 Section 2.4).
511 * We check unspecified / multicast addresses here,
512 * and anycast addresses will be checked later.
513 */
514 if ((addr_type == IPV6_ADDR_ANY) || (addr_type & IPV6_ADDR_MULTICAST)) {
515 net_dbg_ratelimited("icmp6_send: addr_any/mcast source [%pI6c > %pI6c]\n",
516 &hdr->saddr, &hdr->daddr);
517 return;
518 }
519
520 /*
521 * Never answer to a ICMP packet.
522 */
523 if (is_ineligible(skb)) {
524 net_dbg_ratelimited("icmp6_send: no reply to icmp error [%pI6c > %pI6c]\n",
525 &hdr->saddr, &hdr->daddr);
526 return;
527 }
528
529 /* Needed by both icmp_global_allow and icmpv6_xmit_lock */
530 local_bh_disable();
531
532 /* Check global sysctl_icmp_msgs_per_sec ratelimit */
533 if (!(skb->dev->flags & IFF_LOOPBACK) && !icmpv6_global_allow(net, type))
534 goto out_bh_enable;
535
536 mip6_addr_swap(skb);
537
538 sk = icmpv6_xmit_lock(net);
539 if (!sk)
540 goto out_bh_enable;
541
542 memset(&fl6, 0, sizeof(fl6));
543 fl6.flowi6_proto = IPPROTO_ICMPV6;
544 fl6.daddr = hdr->saddr;
545 if (force_saddr)
546 saddr = force_saddr;
547 if (saddr) {
548 fl6.saddr = *saddr;
549 } else if (!icmpv6_rt_has_prefsrc(sk, type, &fl6)) {
550 /* select a more meaningful saddr from input if */
551 struct net_device *in_netdev;
552
553 in_netdev = dev_get_by_index(net, IP6CB(skb)->iif);
554 if (in_netdev) {
555 ipv6_dev_get_saddr(net, in_netdev, &fl6.daddr,
556 inet6_sk(sk)->srcprefs,
557 &fl6.saddr);
558 dev_put(in_netdev);
559 }
560 }
561 fl6.flowi6_mark = mark;
562 fl6.flowi6_oif = iif;
563 fl6.fl6_icmp_type = type;
564 fl6.fl6_icmp_code = code;
565 fl6.flowi6_uid = sock_net_uid(net, NULL);
566 fl6.mp_hash = rt6_multipath_hash(net, &fl6, skb, NULL);
567 security_skb_classify_flow(skb, flowi6_to_flowi(&fl6));
568
569 np = inet6_sk(sk);
570
571 if (!icmpv6_xrlim_allow(sk, type, &fl6))
572 goto out;
573
574 tmp_hdr.icmp6_type = type;
575 tmp_hdr.icmp6_code = code;
576 tmp_hdr.icmp6_cksum = 0;
577 tmp_hdr.icmp6_pointer = htonl(info);
578
579 if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr))
580 fl6.flowi6_oif = np->mcast_oif;
581 else if (!fl6.flowi6_oif)
582 fl6.flowi6_oif = np->ucast_oif;
583
584 ipcm6_init_sk(&ipc6, np);
585 ipc6.sockc.mark = mark;
586 fl6.flowlabel = ip6_make_flowinfo(ipc6.tclass, fl6.flowlabel);
587
588 dst = icmpv6_route_lookup(net, skb, sk, &fl6);
589 if (IS_ERR(dst))
590 goto out;
591
592 ipc6.hlimit = ip6_sk_dst_hoplimit(np, &fl6, dst);
593
594 msg.skb = skb;
595 msg.offset = skb_network_offset(skb);
596 msg.type = type;
597
598 len = skb->len - msg.offset;
599 len = min_t(unsigned int, len, IPV6_MIN_MTU - sizeof(struct ipv6hdr) - sizeof(struct icmp6hdr));
600 if (len < 0) {
601 net_dbg_ratelimited("icmp: len problem [%pI6c > %pI6c]\n",
602 &hdr->saddr, &hdr->daddr);
603 goto out_dst_release;
604 }
605
606 rcu_read_lock();
607 idev = __in6_dev_get(skb->dev);
608
609 if (ip6_append_data(sk, icmpv6_getfrag, &msg,
610 len + sizeof(struct icmp6hdr),
611 sizeof(struct icmp6hdr),
612 &ipc6, &fl6, (struct rt6_info *)dst,
613 MSG_DONTWAIT)) {
614 ICMP6_INC_STATS(net, idev, ICMP6_MIB_OUTERRORS);
615 ip6_flush_pending_frames(sk);
616 } else {
617 icmpv6_push_pending_frames(sk, &fl6, &tmp_hdr,
618 len + sizeof(struct icmp6hdr));
619 }
620 rcu_read_unlock();
621out_dst_release:
622 dst_release(dst);
623out:
624 icmpv6_xmit_unlock(sk);
625out_bh_enable:
626 local_bh_enable();
627}
628EXPORT_SYMBOL(icmp6_send);
629
630/* Slightly more convenient version of icmp6_send.
631 */
632void icmpv6_param_prob(struct sk_buff *skb, u8 code, int pos)
633{
634 icmp6_send(skb, ICMPV6_PARAMPROB, code, pos, NULL);
635 kfree_skb(skb);
636}
637
638/* Generate icmpv6 with type/code ICMPV6_DEST_UNREACH/ICMPV6_ADDR_UNREACH
639 * if sufficient data bytes are available
640 * @nhs is the size of the tunnel header(s) :
641 * Either an IPv4 header for SIT encap
642 * an IPv4 header + GRE header for GRE encap
643 */
644int ip6_err_gen_icmpv6_unreach(struct sk_buff *skb, int nhs, int type,
645 unsigned int data_len)
646{
647 struct in6_addr temp_saddr;
648 struct rt6_info *rt;
649 struct sk_buff *skb2;
650 u32 info = 0;
651
652 if (!pskb_may_pull(skb, nhs + sizeof(struct ipv6hdr) + 8))
653 return 1;
654
655 /* RFC 4884 (partial) support for ICMP extensions */
656 if (data_len < 128 || (data_len & 7) || skb->len < data_len)
657 data_len = 0;
658
659 skb2 = data_len ? skb_copy(skb, GFP_ATOMIC) : skb_clone(skb, GFP_ATOMIC);
660
661 if (!skb2)
662 return 1;
663
664 skb_dst_drop(skb2);
665 skb_pull(skb2, nhs);
666 skb_reset_network_header(skb2);
667
668 rt = rt6_lookup(dev_net(skb->dev), &ipv6_hdr(skb2)->saddr, NULL, 0,
669 skb, 0);
670
671 if (rt && rt->dst.dev)
672 skb2->dev = rt->dst.dev;
673
674 ipv6_addr_set_v4mapped(ip_hdr(skb)->saddr, &temp_saddr);
675
676 if (data_len) {
677 /* RFC 4884 (partial) support :
678 * insert 0 padding at the end, before the extensions
679 */
680 __skb_push(skb2, nhs);
681 skb_reset_network_header(skb2);
682 memmove(skb2->data, skb2->data + nhs, data_len - nhs);
683 memset(skb2->data + data_len - nhs, 0, nhs);
684 /* RFC 4884 4.5 : Length is measured in 64-bit words,
685 * and stored in reserved[0]
686 */
687 info = (data_len/8) << 24;
688 }
689 if (type == ICMP_TIME_EXCEEDED)
690 icmp6_send(skb2, ICMPV6_TIME_EXCEED, ICMPV6_EXC_HOPLIMIT,
691 info, &temp_saddr);
692 else
693 icmp6_send(skb2, ICMPV6_DEST_UNREACH, ICMPV6_ADDR_UNREACH,
694 info, &temp_saddr);
695 if (rt)
696 ip6_rt_put(rt);
697
698 kfree_skb(skb2);
699
700 return 0;
701}
702EXPORT_SYMBOL(ip6_err_gen_icmpv6_unreach);
703
704static void icmpv6_echo_reply(struct sk_buff *skb)
705{
706 struct net *net = dev_net(skb->dev);
707 struct sock *sk;
708 struct inet6_dev *idev;
709 struct ipv6_pinfo *np;
710 const struct in6_addr *saddr = NULL;
711 struct icmp6hdr *icmph = icmp6_hdr(skb);
712 struct icmp6hdr tmp_hdr;
713 struct flowi6 fl6;
714 struct icmpv6_msg msg;
715 struct dst_entry *dst;
716 struct ipcm6_cookie ipc6;
717 u32 mark = IP6_REPLY_MARK(net, skb->mark);
718 bool acast;
719
720 if (ipv6_addr_is_multicast(&ipv6_hdr(skb)->daddr) &&
721 net->ipv6.sysctl.icmpv6_echo_ignore_multicast)
722 return;
723
724 saddr = &ipv6_hdr(skb)->daddr;
725
726 acast = ipv6_anycast_destination(skb_dst(skb), saddr);
727 if (acast && net->ipv6.sysctl.icmpv6_echo_ignore_anycast)
728 return;
729
730 if (!ipv6_unicast_destination(skb) &&
731 !(net->ipv6.sysctl.anycast_src_echo_reply && acast))
732 saddr = NULL;
733
734 memcpy(&tmp_hdr, icmph, sizeof(tmp_hdr));
735 tmp_hdr.icmp6_type = ICMPV6_ECHO_REPLY;
736
737 memset(&fl6, 0, sizeof(fl6));
738 if (net->ipv6.sysctl.flowlabel_reflect & FLOWLABEL_REFLECT_ICMPV6_ECHO_REPLIES)
739 fl6.flowlabel = ip6_flowlabel(ipv6_hdr(skb));
740
741 fl6.flowi6_proto = IPPROTO_ICMPV6;
742 fl6.daddr = ipv6_hdr(skb)->saddr;
743 if (saddr)
744 fl6.saddr = *saddr;
745 fl6.flowi6_oif = icmp6_iif(skb);
746 fl6.fl6_icmp_type = ICMPV6_ECHO_REPLY;
747 fl6.flowi6_mark = mark;
748 fl6.flowi6_uid = sock_net_uid(net, NULL);
749 security_skb_classify_flow(skb, flowi6_to_flowi(&fl6));
750
751 local_bh_disable();
752 sk = icmpv6_xmit_lock(net);
753 if (!sk)
754 goto out_bh_enable;
755 np = inet6_sk(sk);
756
757 if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr))
758 fl6.flowi6_oif = np->mcast_oif;
759 else if (!fl6.flowi6_oif)
760 fl6.flowi6_oif = np->ucast_oif;
761
762 if (ip6_dst_lookup(net, sk, &dst, &fl6))
763 goto out;
764 dst = xfrm_lookup(net, dst, flowi6_to_flowi(&fl6), sk, 0);
765 if (IS_ERR(dst))
766 goto out;
767
768 /* Check the ratelimit */
769 if ((!(skb->dev->flags & IFF_LOOPBACK) && !icmpv6_global_allow(net, ICMPV6_ECHO_REPLY)) ||
770 !icmpv6_xrlim_allow(sk, ICMPV6_ECHO_REPLY, &fl6))
771 goto out_dst_release;
772
773 idev = __in6_dev_get(skb->dev);
774
775 msg.skb = skb;
776 msg.offset = 0;
777 msg.type = ICMPV6_ECHO_REPLY;
778
779 ipcm6_init_sk(&ipc6, np);
780 ipc6.hlimit = ip6_sk_dst_hoplimit(np, &fl6, dst);
781 ipc6.tclass = ipv6_get_dsfield(ipv6_hdr(skb));
782 ipc6.sockc.mark = mark;
783
784 if (ip6_append_data(sk, icmpv6_getfrag, &msg,
785 skb->len + sizeof(struct icmp6hdr),
786 sizeof(struct icmp6hdr), &ipc6, &fl6,
787 (struct rt6_info *)dst, MSG_DONTWAIT)) {
788 __ICMP6_INC_STATS(net, idev, ICMP6_MIB_OUTERRORS);
789 ip6_flush_pending_frames(sk);
790 } else {
791 icmpv6_push_pending_frames(sk, &fl6, &tmp_hdr,
792 skb->len + sizeof(struct icmp6hdr));
793 }
794out_dst_release:
795 dst_release(dst);
796out:
797 icmpv6_xmit_unlock(sk);
798out_bh_enable:
799 local_bh_enable();
800}
801
802void icmpv6_notify(struct sk_buff *skb, u8 type, u8 code, __be32 info)
803{
804 const struct inet6_protocol *ipprot;
805 int inner_offset;
806 __be16 frag_off;
807 u8 nexthdr;
808 struct net *net = dev_net(skb->dev);
809
810 if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
811 goto out;
812
813 nexthdr = ((struct ipv6hdr *)skb->data)->nexthdr;
814 if (ipv6_ext_hdr(nexthdr)) {
815 /* now skip over extension headers */
816 inner_offset = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr),
817 &nexthdr, &frag_off);
818 if (inner_offset < 0)
819 goto out;
820 } else {
821 inner_offset = sizeof(struct ipv6hdr);
822 }
823
824 /* Checkin header including 8 bytes of inner protocol header. */
825 if (!pskb_may_pull(skb, inner_offset+8))
826 goto out;
827
828 /* BUGGG_FUTURE: we should try to parse exthdrs in this packet.
829 Without this we will not able f.e. to make source routed
830 pmtu discovery.
831 Corresponding argument (opt) to notifiers is already added.
832 --ANK (980726)
833 */
834
835 ipprot = rcu_dereference(inet6_protos[nexthdr]);
836 if (ipprot && ipprot->err_handler)
837 ipprot->err_handler(skb, NULL, type, code, inner_offset, info);
838
839 raw6_icmp_error(skb, nexthdr, type, code, inner_offset, info);
840 return;
841
842out:
843 __ICMP6_INC_STATS(net, __in6_dev_get(skb->dev), ICMP6_MIB_INERRORS);
844}
845
846/*
847 * Handle icmp messages
848 */
849
850static int icmpv6_rcv(struct sk_buff *skb)
851{
852 struct net *net = dev_net(skb->dev);
853 struct net_device *dev = icmp6_dev(skb);
854 struct inet6_dev *idev = __in6_dev_get(dev);
855 const struct in6_addr *saddr, *daddr;
856 struct icmp6hdr *hdr;
857 u8 type;
858 bool success = false;
859
860 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) {
861 struct sec_path *sp = skb_sec_path(skb);
862 int nh;
863
864 if (!(sp && sp->xvec[sp->len - 1]->props.flags &
865 XFRM_STATE_ICMP))
866 goto drop_no_count;
867
868 if (!pskb_may_pull(skb, sizeof(*hdr) + sizeof(struct ipv6hdr)))
869 goto drop_no_count;
870
871 nh = skb_network_offset(skb);
872 skb_set_network_header(skb, sizeof(*hdr));
873
874 if (!xfrm6_policy_check_reverse(NULL, XFRM_POLICY_IN, skb))
875 goto drop_no_count;
876
877 skb_set_network_header(skb, nh);
878 }
879
880 __ICMP6_INC_STATS(dev_net(dev), idev, ICMP6_MIB_INMSGS);
881
882 saddr = &ipv6_hdr(skb)->saddr;
883 daddr = &ipv6_hdr(skb)->daddr;
884
885 if (skb_checksum_validate(skb, IPPROTO_ICMPV6, ip6_compute_pseudo)) {
886 net_dbg_ratelimited("ICMPv6 checksum failed [%pI6c > %pI6c]\n",
887 saddr, daddr);
888 goto csum_error;
889 }
890
891 if (!pskb_pull(skb, sizeof(*hdr)))
892 goto discard_it;
893
894 hdr = icmp6_hdr(skb);
895
896 type = hdr->icmp6_type;
897
898 ICMP6MSGIN_INC_STATS(dev_net(dev), idev, type);
899
900 switch (type) {
901 case ICMPV6_ECHO_REQUEST:
902 if (!net->ipv6.sysctl.icmpv6_echo_ignore_all)
903 icmpv6_echo_reply(skb);
904 break;
905
906 case ICMPV6_ECHO_REPLY:
907 success = ping_rcv(skb);
908 break;
909
910 case ICMPV6_PKT_TOOBIG:
911 /* BUGGG_FUTURE: if packet contains rthdr, we cannot update
912 standard destination cache. Seems, only "advanced"
913 destination cache will allow to solve this problem
914 --ANK (980726)
915 */
916 if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
917 goto discard_it;
918 hdr = icmp6_hdr(skb);
919
920 /* to notify */
921 fallthrough;
922 case ICMPV6_DEST_UNREACH:
923 case ICMPV6_TIME_EXCEED:
924 case ICMPV6_PARAMPROB:
925 icmpv6_notify(skb, type, hdr->icmp6_code, hdr->icmp6_mtu);
926 break;
927
928 case NDISC_ROUTER_SOLICITATION:
929 case NDISC_ROUTER_ADVERTISEMENT:
930 case NDISC_NEIGHBOUR_SOLICITATION:
931 case NDISC_NEIGHBOUR_ADVERTISEMENT:
932 case NDISC_REDIRECT:
933 ndisc_rcv(skb);
934 break;
935
936 case ICMPV6_MGM_QUERY:
937 igmp6_event_query(skb);
938 break;
939
940 case ICMPV6_MGM_REPORT:
941 igmp6_event_report(skb);
942 break;
943
944 case ICMPV6_MGM_REDUCTION:
945 case ICMPV6_NI_QUERY:
946 case ICMPV6_NI_REPLY:
947 case ICMPV6_MLD2_REPORT:
948 case ICMPV6_DHAAD_REQUEST:
949 case ICMPV6_DHAAD_REPLY:
950 case ICMPV6_MOBILE_PREFIX_SOL:
951 case ICMPV6_MOBILE_PREFIX_ADV:
952 break;
953
954 default:
955 /* informational */
956 if (type & ICMPV6_INFOMSG_MASK)
957 break;
958
959 net_dbg_ratelimited("icmpv6: msg of unknown type [%pI6c > %pI6c]\n",
960 saddr, daddr);
961
962 /*
963 * error of unknown type.
964 * must pass to upper level
965 */
966
967 icmpv6_notify(skb, type, hdr->icmp6_code, hdr->icmp6_mtu);
968 }
969
970 /* until the v6 path can be better sorted assume failure and
971 * preserve the status quo behaviour for the rest of the paths to here
972 */
973 if (success)
974 consume_skb(skb);
975 else
976 kfree_skb(skb);
977
978 return 0;
979
980csum_error:
981 __ICMP6_INC_STATS(dev_net(dev), idev, ICMP6_MIB_CSUMERRORS);
982discard_it:
983 __ICMP6_INC_STATS(dev_net(dev), idev, ICMP6_MIB_INERRORS);
984drop_no_count:
985 kfree_skb(skb);
986 return 0;
987}
988
989void icmpv6_flow_init(struct sock *sk, struct flowi6 *fl6,
990 u8 type,
991 const struct in6_addr *saddr,
992 const struct in6_addr *daddr,
993 int oif)
994{
995 memset(fl6, 0, sizeof(*fl6));
996 fl6->saddr = *saddr;
997 fl6->daddr = *daddr;
998 fl6->flowi6_proto = IPPROTO_ICMPV6;
999 fl6->fl6_icmp_type = type;
1000 fl6->fl6_icmp_code = 0;
1001 fl6->flowi6_oif = oif;
1002 security_sk_classify_flow(sk, flowi6_to_flowi(fl6));
1003}
1004
1005static void __net_exit icmpv6_sk_exit(struct net *net)
1006{
1007 int i;
1008
1009 for_each_possible_cpu(i)
1010 inet_ctl_sock_destroy(*per_cpu_ptr(net->ipv6.icmp_sk, i));
1011 free_percpu(net->ipv6.icmp_sk);
1012}
1013
1014static int __net_init icmpv6_sk_init(struct net *net)
1015{
1016 struct sock *sk;
1017 int err, i;
1018
1019 net->ipv6.icmp_sk = alloc_percpu(struct sock *);
1020 if (!net->ipv6.icmp_sk)
1021 return -ENOMEM;
1022
1023 for_each_possible_cpu(i) {
1024 err = inet_ctl_sock_create(&sk, PF_INET6,
1025 SOCK_RAW, IPPROTO_ICMPV6, net);
1026 if (err < 0) {
1027 pr_err("Failed to initialize the ICMP6 control socket (err %d)\n",
1028 err);
1029 goto fail;
1030 }
1031
1032 *per_cpu_ptr(net->ipv6.icmp_sk, i) = sk;
1033
1034 /* Enough space for 2 64K ICMP packets, including
1035 * sk_buff struct overhead.
1036 */
1037 sk->sk_sndbuf = 2 * SKB_TRUESIZE(64 * 1024);
1038 }
1039 return 0;
1040
1041 fail:
1042 icmpv6_sk_exit(net);
1043 return err;
1044}
1045
1046static struct pernet_operations icmpv6_sk_ops = {
1047 .init = icmpv6_sk_init,
1048 .exit = icmpv6_sk_exit,
1049};
1050
1051int __init icmpv6_init(void)
1052{
1053 int err;
1054
1055 err = register_pernet_subsys(&icmpv6_sk_ops);
1056 if (err < 0)
1057 return err;
1058
1059 err = -EAGAIN;
1060 if (inet6_add_protocol(&icmpv6_protocol, IPPROTO_ICMPV6) < 0)
1061 goto fail;
1062
1063 err = inet6_register_icmp_sender(icmp6_send);
1064 if (err)
1065 goto sender_reg_err;
1066 return 0;
1067
1068sender_reg_err:
1069 inet6_del_protocol(&icmpv6_protocol, IPPROTO_ICMPV6);
1070fail:
1071 pr_err("Failed to register ICMP6 protocol\n");
1072 unregister_pernet_subsys(&icmpv6_sk_ops);
1073 return err;
1074}
1075
1076void icmpv6_cleanup(void)
1077{
1078 inet6_unregister_icmp_sender(icmp6_send);
1079 unregister_pernet_subsys(&icmpv6_sk_ops);
1080 inet6_del_protocol(&icmpv6_protocol, IPPROTO_ICMPV6);
1081}
1082
1083
1084static const struct icmp6_err {
1085 int err;
1086 int fatal;
1087} tab_unreach[] = {
1088 { /* NOROUTE */
1089 .err = ENETUNREACH,
1090 .fatal = 0,
1091 },
1092 { /* ADM_PROHIBITED */
1093 .err = EACCES,
1094 .fatal = 1,
1095 },
1096 { /* Was NOT_NEIGHBOUR, now reserved */
1097 .err = EHOSTUNREACH,
1098 .fatal = 0,
1099 },
1100 { /* ADDR_UNREACH */
1101 .err = EHOSTUNREACH,
1102 .fatal = 0,
1103 },
1104 { /* PORT_UNREACH */
1105 .err = ECONNREFUSED,
1106 .fatal = 1,
1107 },
1108 { /* POLICY_FAIL */
1109 .err = EACCES,
1110 .fatal = 1,
1111 },
1112 { /* REJECT_ROUTE */
1113 .err = EACCES,
1114 .fatal = 1,
1115 },
1116};
1117
1118int icmpv6_err_convert(u8 type, u8 code, int *err)
1119{
1120 int fatal = 0;
1121
1122 *err = EPROTO;
1123
1124 switch (type) {
1125 case ICMPV6_DEST_UNREACH:
1126 fatal = 1;
1127 if (code < ARRAY_SIZE(tab_unreach)) {
1128 *err = tab_unreach[code].err;
1129 fatal = tab_unreach[code].fatal;
1130 }
1131 break;
1132
1133 case ICMPV6_PKT_TOOBIG:
1134 *err = EMSGSIZE;
1135 break;
1136
1137 case ICMPV6_PARAMPROB:
1138 *err = EPROTO;
1139 fatal = 1;
1140 break;
1141
1142 case ICMPV6_TIME_EXCEED:
1143 *err = EHOSTUNREACH;
1144 break;
1145 }
1146
1147 return fatal;
1148}
1149EXPORT_SYMBOL(icmpv6_err_convert);
1150
1151#ifdef CONFIG_SYSCTL
1152static struct ctl_table ipv6_icmp_table_template[] = {
1153 {
1154 .procname = "ratelimit",
1155 .data = &init_net.ipv6.sysctl.icmpv6_time,
1156 .maxlen = sizeof(int),
1157 .mode = 0644,
1158 .proc_handler = proc_dointvec_ms_jiffies,
1159 },
1160 {
1161 .procname = "echo_ignore_all",
1162 .data = &init_net.ipv6.sysctl.icmpv6_echo_ignore_all,
1163 .maxlen = sizeof(int),
1164 .mode = 0644,
1165 .proc_handler = proc_dointvec,
1166 },
1167 {
1168 .procname = "echo_ignore_multicast",
1169 .data = &init_net.ipv6.sysctl.icmpv6_echo_ignore_multicast,
1170 .maxlen = sizeof(int),
1171 .mode = 0644,
1172 .proc_handler = proc_dointvec,
1173 },
1174 {
1175 .procname = "echo_ignore_anycast",
1176 .data = &init_net.ipv6.sysctl.icmpv6_echo_ignore_anycast,
1177 .maxlen = sizeof(int),
1178 .mode = 0644,
1179 .proc_handler = proc_dointvec,
1180 },
1181 {
1182 .procname = "ratemask",
1183 .data = &init_net.ipv6.sysctl.icmpv6_ratemask_ptr,
1184 .maxlen = ICMPV6_MSG_MAX + 1,
1185 .mode = 0644,
1186 .proc_handler = proc_do_large_bitmap,
1187 },
1188 { },
1189};
1190
1191struct ctl_table * __net_init ipv6_icmp_sysctl_init(struct net *net)
1192{
1193 struct ctl_table *table;
1194
1195 table = kmemdup(ipv6_icmp_table_template,
1196 sizeof(ipv6_icmp_table_template),
1197 GFP_KERNEL);
1198
1199 if (table) {
1200 table[0].data = &net->ipv6.sysctl.icmpv6_time;
1201 table[1].data = &net->ipv6.sysctl.icmpv6_echo_ignore_all;
1202 table[2].data = &net->ipv6.sysctl.icmpv6_echo_ignore_multicast;
1203 table[3].data = &net->ipv6.sysctl.icmpv6_echo_ignore_anycast;
1204 table[4].data = &net->ipv6.sysctl.icmpv6_ratemask_ptr;
1205 }
1206 return table;
1207}
1208#endif
1/*
2 * Internet Control Message Protocol (ICMPv6)
3 * Linux INET6 implementation
4 *
5 * Authors:
6 * Pedro Roque <roque@di.fc.ul.pt>
7 *
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>
38#include <linux/sockios.h>
39#include <linux/net.h>
40#include <linux/skbuff.h>
41#include <linux/init.h>
42#include <linux/netfilter.h>
43#include <linux/slab.h>
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>
65#include <net/xfrm.h>
66#include <net/inet_common.h>
67
68#include <asm/uaccess.h>
69#include <asm/system.h>
70
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 */
78static inline struct sock *icmpv6_sk(struct net *net)
79{
80 return net->ipv6.icmp_sk[smp_processor_id()];
81}
82
83static int icmpv6_rcv(struct sk_buff *skb);
84
85static const struct inet6_protocol icmpv6_protocol = {
86 .handler = icmpv6_rcv,
87 .flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
88};
89
90static __inline__ struct sock *icmpv6_xmit_lock(struct net *net)
91{
92 struct sock *sk;
93
94 local_bh_disable();
95
96 sk = icmpv6_sk(net);
97 if (unlikely(!spin_trylock(&sk->sk_lock.slock))) {
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();
103 return NULL;
104 }
105 return sk;
106}
107
108static __inline__ void icmpv6_xmit_unlock(struct sock *sk)
109{
110 spin_unlock_bh(&sk->sk_lock.slock);
111}
112
113/*
114 * Slightly more convenient version of icmpv6_send.
115 */
116void icmpv6_param_prob(struct sk_buff *skb, u8 code, int pos)
117{
118 icmpv6_send(skb, ICMPV6_PARAMPROB, code, pos);
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{
135 int ptr = (u8 *)(ipv6_hdr(skb) + 1) - skb->data;
136 int len = skb->len - ptr;
137 __u8 nexthdr = ipv6_hdr(skb)->nexthdr;
138
139 if (len < 0)
140 return 1;
141
142 ptr = ipv6_skip_exthdr(skb, ptr, &nexthdr);
143 if (ptr < 0)
144 return 0;
145 if (nexthdr == IPPROTO_ICMPV6) {
146 u8 _type, *tp;
147 tp = skb_header_pointer(skb,
148 ptr+offsetof(struct icmp6hdr, icmp6_type),
149 sizeof(_type), &_type);
150 if (tp == NULL ||
151 !(*tp & ICMPV6_INFOMSG_MASK))
152 return 1;
153 }
154 return 0;
155}
156
157/*
158 * Check the ICMP output rate limit
159 */
160static inline bool icmpv6_xrlim_allow(struct sock *sk, u8 type,
161 struct flowi6 *fl6)
162{
163 struct dst_entry *dst;
164 struct net *net = sock_net(sk);
165 bool res = false;
166
167 /* Informational messages are not limited. */
168 if (type & ICMPV6_INFOMSG_MASK)
169 return true;
170
171 /* Do not limit pmtu discovery, it would break it. */
172 if (type == ICMPV6_PKT_TOOBIG)
173 return true;
174
175 /*
176 * Look up the output route.
177 * XXX: perhaps the expire for routing entries cloned by
178 * this lookup should be more aggressive (not longer than timeout).
179 */
180 dst = ip6_route_output(net, sk, fl6);
181 if (dst->error) {
182 IP6_INC_STATS(net, ip6_dst_idev(dst),
183 IPSTATS_MIB_OUTNOROUTES);
184 } else if (dst->dev && (dst->dev->flags&IFF_LOOPBACK)) {
185 res = true;
186 } else {
187 struct rt6_info *rt = (struct rt6_info *)dst;
188 int tmo = net->ipv6.sysctl.icmpv6_time;
189
190 /* Give more bandwidth to wider prefixes. */
191 if (rt->rt6i_dst.plen < 128)
192 tmo >>= ((128 - rt->rt6i_dst.plen)>>5);
193
194 if (!rt->rt6i_peer)
195 rt6_bind_peer(rt, 1);
196 res = inet_peer_xrlim_allow(rt->rt6i_peer, tmo);
197 }
198 dst_release(dst);
199 return res;
200}
201
202/*
203 * an inline helper for the "simple" if statement below
204 * checks if parameter problem report is caused by an
205 * unrecognized IPv6 option that has the Option Type
206 * highest-order two bits set to 10
207 */
208
209static __inline__ int opt_unrec(struct sk_buff *skb, __u32 offset)
210{
211 u8 _optval, *op;
212
213 offset += skb_network_offset(skb);
214 op = skb_header_pointer(skb, offset, sizeof(_optval), &_optval);
215 if (op == NULL)
216 return 1;
217 return (*op & 0xC0) == 0x80;
218}
219
220static int icmpv6_push_pending_frames(struct sock *sk, struct flowi6 *fl6, struct icmp6hdr *thdr, int len)
221{
222 struct sk_buff *skb;
223 struct icmp6hdr *icmp6h;
224 int err = 0;
225
226 if ((skb = skb_peek(&sk->sk_write_queue)) == NULL)
227 goto out;
228
229 icmp6h = icmp6_hdr(skb);
230 memcpy(icmp6h, thdr, sizeof(struct icmp6hdr));
231 icmp6h->icmp6_cksum = 0;
232
233 if (skb_queue_len(&sk->sk_write_queue) == 1) {
234 skb->csum = csum_partial(icmp6h,
235 sizeof(struct icmp6hdr), skb->csum);
236 icmp6h->icmp6_cksum = csum_ipv6_magic(&fl6->saddr,
237 &fl6->daddr,
238 len, fl6->flowi6_proto,
239 skb->csum);
240 } else {
241 __wsum tmp_csum = 0;
242
243 skb_queue_walk(&sk->sk_write_queue, skb) {
244 tmp_csum = csum_add(tmp_csum, skb->csum);
245 }
246
247 tmp_csum = csum_partial(icmp6h,
248 sizeof(struct icmp6hdr), tmp_csum);
249 icmp6h->icmp6_cksum = csum_ipv6_magic(&fl6->saddr,
250 &fl6->daddr,
251 len, fl6->flowi6_proto,
252 tmp_csum);
253 }
254 ip6_push_pending_frames(sk);
255out:
256 return err;
257}
258
259struct icmpv6_msg {
260 struct sk_buff *skb;
261 int offset;
262 uint8_t type;
263};
264
265static int icmpv6_getfrag(void *from, char *to, int offset, int len, int odd, struct sk_buff *skb)
266{
267 struct icmpv6_msg *msg = (struct icmpv6_msg *) from;
268 struct sk_buff *org_skb = msg->skb;
269 __wsum csum = 0;
270
271 csum = skb_copy_and_csum_bits(org_skb, msg->offset + offset,
272 to, len, csum);
273 skb->csum = csum_block_add(skb->csum, csum, odd);
274 if (!(msg->type & ICMPV6_INFOMSG_MASK))
275 nf_ct_attach(skb, org_skb);
276 return 0;
277}
278
279#if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
280static void mip6_addr_swap(struct sk_buff *skb)
281{
282 struct ipv6hdr *iph = ipv6_hdr(skb);
283 struct inet6_skb_parm *opt = IP6CB(skb);
284 struct ipv6_destopt_hao *hao;
285 struct in6_addr tmp;
286 int off;
287
288 if (opt->dsthao) {
289 off = ipv6_find_tlv(skb, opt->dsthao, IPV6_TLV_HAO);
290 if (likely(off >= 0)) {
291 hao = (struct ipv6_destopt_hao *)
292 (skb_network_header(skb) + off);
293 ipv6_addr_copy(&tmp, &iph->saddr);
294 ipv6_addr_copy(&iph->saddr, &hao->addr);
295 ipv6_addr_copy(&hao->addr, &tmp);
296 }
297 }
298}
299#else
300static inline void mip6_addr_swap(struct sk_buff *skb) {}
301#endif
302
303static struct dst_entry *icmpv6_route_lookup(struct net *net, struct sk_buff *skb,
304 struct sock *sk, struct flowi6 *fl6)
305{
306 struct dst_entry *dst, *dst2;
307 struct flowi6 fl2;
308 int err;
309
310 err = ip6_dst_lookup(sk, &dst, fl6);
311 if (err)
312 return ERR_PTR(err);
313
314 /*
315 * We won't send icmp if the destination is known
316 * anycast.
317 */
318 if (((struct rt6_info *)dst)->rt6i_flags & RTF_ANYCAST) {
319 LIMIT_NETDEBUG(KERN_DEBUG "icmpv6_send: acast source\n");
320 dst_release(dst);
321 return ERR_PTR(-EINVAL);
322 }
323
324 /* No need to clone since we're just using its address. */
325 dst2 = dst;
326
327 dst = xfrm_lookup(net, dst, flowi6_to_flowi(fl6), sk, 0);
328 if (!IS_ERR(dst)) {
329 if (dst != dst2)
330 return dst;
331 } else {
332 if (PTR_ERR(dst) == -EPERM)
333 dst = NULL;
334 else
335 return dst;
336 }
337
338 err = xfrm_decode_session_reverse(skb, flowi6_to_flowi(&fl2), AF_INET6);
339 if (err)
340 goto relookup_failed;
341
342 err = ip6_dst_lookup(sk, &dst2, &fl2);
343 if (err)
344 goto relookup_failed;
345
346 dst2 = xfrm_lookup(net, dst2, flowi6_to_flowi(&fl2), sk, XFRM_LOOKUP_ICMP);
347 if (!IS_ERR(dst2)) {
348 dst_release(dst);
349 dst = dst2;
350 } else {
351 err = PTR_ERR(dst2);
352 if (err == -EPERM) {
353 dst_release(dst);
354 return dst2;
355 } else
356 goto relookup_failed;
357 }
358
359relookup_failed:
360 if (dst)
361 return dst;
362 return ERR_PTR(err);
363}
364
365/*
366 * Send an ICMP message in response to a packet in error
367 */
368void icmpv6_send(struct sk_buff *skb, u8 type, u8 code, __u32 info)
369{
370 struct net *net = dev_net(skb->dev);
371 struct inet6_dev *idev = NULL;
372 struct ipv6hdr *hdr = ipv6_hdr(skb);
373 struct sock *sk;
374 struct ipv6_pinfo *np;
375 const struct in6_addr *saddr = NULL;
376 struct dst_entry *dst;
377 struct icmp6hdr tmp_hdr;
378 struct flowi6 fl6;
379 struct icmpv6_msg msg;
380 int iif = 0;
381 int addr_type = 0;
382 int len;
383 int hlimit;
384 int err = 0;
385
386 if ((u8 *)hdr < skb->head ||
387 (skb->network_header + sizeof(*hdr)) > skb->tail)
388 return;
389
390 /*
391 * Make sure we respect the rules
392 * i.e. RFC 1885 2.4(e)
393 * Rule (e.1) is enforced by not using icmpv6_send
394 * in any code that processes icmp errors.
395 */
396 addr_type = ipv6_addr_type(&hdr->daddr);
397
398 if (ipv6_chk_addr(net, &hdr->daddr, skb->dev, 0))
399 saddr = &hdr->daddr;
400
401 /*
402 * Dest addr check
403 */
404
405 if ((addr_type & IPV6_ADDR_MULTICAST || skb->pkt_type != PACKET_HOST)) {
406 if (type != ICMPV6_PKT_TOOBIG &&
407 !(type == ICMPV6_PARAMPROB &&
408 code == ICMPV6_UNK_OPTION &&
409 (opt_unrec(skb, info))))
410 return;
411
412 saddr = NULL;
413 }
414
415 addr_type = ipv6_addr_type(&hdr->saddr);
416
417 /*
418 * Source addr check
419 */
420
421 if (addr_type & IPV6_ADDR_LINKLOCAL)
422 iif = skb->dev->ifindex;
423
424 /*
425 * Must not send error if the source does not uniquely
426 * identify a single node (RFC2463 Section 2.4).
427 * We check unspecified / multicast addresses here,
428 * and anycast addresses will be checked later.
429 */
430 if ((addr_type == IPV6_ADDR_ANY) || (addr_type & IPV6_ADDR_MULTICAST)) {
431 LIMIT_NETDEBUG(KERN_DEBUG "icmpv6_send: addr_any/mcast source\n");
432 return;
433 }
434
435 /*
436 * Never answer to a ICMP packet.
437 */
438 if (is_ineligible(skb)) {
439 LIMIT_NETDEBUG(KERN_DEBUG "icmpv6_send: no reply to icmp error\n");
440 return;
441 }
442
443 mip6_addr_swap(skb);
444
445 memset(&fl6, 0, sizeof(fl6));
446 fl6.flowi6_proto = IPPROTO_ICMPV6;
447 ipv6_addr_copy(&fl6.daddr, &hdr->saddr);
448 if (saddr)
449 ipv6_addr_copy(&fl6.saddr, saddr);
450 fl6.flowi6_oif = iif;
451 fl6.fl6_icmp_type = type;
452 fl6.fl6_icmp_code = code;
453 security_skb_classify_flow(skb, flowi6_to_flowi(&fl6));
454
455 sk = icmpv6_xmit_lock(net);
456 if (sk == NULL)
457 return;
458 np = inet6_sk(sk);
459
460 if (!icmpv6_xrlim_allow(sk, type, &fl6))
461 goto out;
462
463 tmp_hdr.icmp6_type = type;
464 tmp_hdr.icmp6_code = code;
465 tmp_hdr.icmp6_cksum = 0;
466 tmp_hdr.icmp6_pointer = htonl(info);
467
468 if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr))
469 fl6.flowi6_oif = np->mcast_oif;
470
471 dst = icmpv6_route_lookup(net, skb, sk, &fl6);
472 if (IS_ERR(dst))
473 goto out;
474
475 if (ipv6_addr_is_multicast(&fl6.daddr))
476 hlimit = np->mcast_hops;
477 else
478 hlimit = np->hop_limit;
479 if (hlimit < 0)
480 hlimit = ip6_dst_hoplimit(dst);
481
482 msg.skb = skb;
483 msg.offset = skb_network_offset(skb);
484 msg.type = type;
485
486 len = skb->len - msg.offset;
487 len = min_t(unsigned int, len, IPV6_MIN_MTU - sizeof(struct ipv6hdr) -sizeof(struct icmp6hdr));
488 if (len < 0) {
489 LIMIT_NETDEBUG(KERN_DEBUG "icmp: len problem\n");
490 goto out_dst_release;
491 }
492
493 idev = in6_dev_get(skb->dev);
494
495 err = ip6_append_data(sk, icmpv6_getfrag, &msg,
496 len + sizeof(struct icmp6hdr),
497 sizeof(struct icmp6hdr), hlimit,
498 np->tclass, NULL, &fl6, (struct rt6_info*)dst,
499 MSG_DONTWAIT, np->dontfrag);
500 if (err) {
501 ICMP6_INC_STATS_BH(net, idev, ICMP6_MIB_OUTERRORS);
502 ip6_flush_pending_frames(sk);
503 goto out_put;
504 }
505 err = icmpv6_push_pending_frames(sk, &fl6, &tmp_hdr, len + sizeof(struct icmp6hdr));
506
507out_put:
508 if (likely(idev != NULL))
509 in6_dev_put(idev);
510out_dst_release:
511 dst_release(dst);
512out:
513 icmpv6_xmit_unlock(sk);
514}
515
516EXPORT_SYMBOL(icmpv6_send);
517
518static void icmpv6_echo_reply(struct sk_buff *skb)
519{
520 struct net *net = dev_net(skb->dev);
521 struct sock *sk;
522 struct inet6_dev *idev;
523 struct ipv6_pinfo *np;
524 const struct in6_addr *saddr = NULL;
525 struct icmp6hdr *icmph = icmp6_hdr(skb);
526 struct icmp6hdr tmp_hdr;
527 struct flowi6 fl6;
528 struct icmpv6_msg msg;
529 struct dst_entry *dst;
530 int err = 0;
531 int hlimit;
532
533 saddr = &ipv6_hdr(skb)->daddr;
534
535 if (!ipv6_unicast_destination(skb))
536 saddr = NULL;
537
538 memcpy(&tmp_hdr, icmph, sizeof(tmp_hdr));
539 tmp_hdr.icmp6_type = ICMPV6_ECHO_REPLY;
540
541 memset(&fl6, 0, sizeof(fl6));
542 fl6.flowi6_proto = IPPROTO_ICMPV6;
543 ipv6_addr_copy(&fl6.daddr, &ipv6_hdr(skb)->saddr);
544 if (saddr)
545 ipv6_addr_copy(&fl6.saddr, saddr);
546 fl6.flowi6_oif = skb->dev->ifindex;
547 fl6.fl6_icmp_type = ICMPV6_ECHO_REPLY;
548 security_skb_classify_flow(skb, flowi6_to_flowi(&fl6));
549
550 sk = icmpv6_xmit_lock(net);
551 if (sk == NULL)
552 return;
553 np = inet6_sk(sk);
554
555 if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr))
556 fl6.flowi6_oif = np->mcast_oif;
557
558 err = ip6_dst_lookup(sk, &dst, &fl6);
559 if (err)
560 goto out;
561 dst = xfrm_lookup(net, dst, flowi6_to_flowi(&fl6), sk, 0);
562 if (IS_ERR(dst))
563 goto out;
564
565 if (ipv6_addr_is_multicast(&fl6.daddr))
566 hlimit = np->mcast_hops;
567 else
568 hlimit = np->hop_limit;
569 if (hlimit < 0)
570 hlimit = ip6_dst_hoplimit(dst);
571
572 idev = in6_dev_get(skb->dev);
573
574 msg.skb = skb;
575 msg.offset = 0;
576 msg.type = ICMPV6_ECHO_REPLY;
577
578 err = ip6_append_data(sk, icmpv6_getfrag, &msg, skb->len + sizeof(struct icmp6hdr),
579 sizeof(struct icmp6hdr), hlimit, np->tclass, NULL, &fl6,
580 (struct rt6_info*)dst, MSG_DONTWAIT,
581 np->dontfrag);
582
583 if (err) {
584 ICMP6_INC_STATS_BH(net, idev, ICMP6_MIB_OUTERRORS);
585 ip6_flush_pending_frames(sk);
586 goto out_put;
587 }
588 err = icmpv6_push_pending_frames(sk, &fl6, &tmp_hdr, skb->len + sizeof(struct icmp6hdr));
589
590out_put:
591 if (likely(idev != NULL))
592 in6_dev_put(idev);
593 dst_release(dst);
594out:
595 icmpv6_xmit_unlock(sk);
596}
597
598static void icmpv6_notify(struct sk_buff *skb, u8 type, u8 code, __be32 info)
599{
600 const struct inet6_protocol *ipprot;
601 int inner_offset;
602 int hash;
603 u8 nexthdr;
604
605 if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
606 return;
607
608 nexthdr = ((struct ipv6hdr *)skb->data)->nexthdr;
609 if (ipv6_ext_hdr(nexthdr)) {
610 /* now skip over extension headers */
611 inner_offset = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr), &nexthdr);
612 if (inner_offset<0)
613 return;
614 } else {
615 inner_offset = sizeof(struct ipv6hdr);
616 }
617
618 /* Checkin header including 8 bytes of inner protocol header. */
619 if (!pskb_may_pull(skb, inner_offset+8))
620 return;
621
622 /* BUGGG_FUTURE: we should try to parse exthdrs in this packet.
623 Without this we will not able f.e. to make source routed
624 pmtu discovery.
625 Corresponding argument (opt) to notifiers is already added.
626 --ANK (980726)
627 */
628
629 hash = nexthdr & (MAX_INET_PROTOS - 1);
630
631 rcu_read_lock();
632 ipprot = rcu_dereference(inet6_protos[hash]);
633 if (ipprot && ipprot->err_handler)
634 ipprot->err_handler(skb, NULL, type, code, inner_offset, info);
635 rcu_read_unlock();
636
637 raw6_icmp_error(skb, nexthdr, type, code, inner_offset, info);
638}
639
640/*
641 * Handle icmp messages
642 */
643
644static int icmpv6_rcv(struct sk_buff *skb)
645{
646 struct net_device *dev = skb->dev;
647 struct inet6_dev *idev = __in6_dev_get(dev);
648 const struct in6_addr *saddr, *daddr;
649 const struct ipv6hdr *orig_hdr;
650 struct icmp6hdr *hdr;
651 u8 type;
652
653 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) {
654 struct sec_path *sp = skb_sec_path(skb);
655 int nh;
656
657 if (!(sp && sp->xvec[sp->len - 1]->props.flags &
658 XFRM_STATE_ICMP))
659 goto drop_no_count;
660
661 if (!pskb_may_pull(skb, sizeof(*hdr) + sizeof(*orig_hdr)))
662 goto drop_no_count;
663
664 nh = skb_network_offset(skb);
665 skb_set_network_header(skb, sizeof(*hdr));
666
667 if (!xfrm6_policy_check_reverse(NULL, XFRM_POLICY_IN, skb))
668 goto drop_no_count;
669
670 skb_set_network_header(skb, nh);
671 }
672
673 ICMP6_INC_STATS_BH(dev_net(dev), idev, ICMP6_MIB_INMSGS);
674
675 saddr = &ipv6_hdr(skb)->saddr;
676 daddr = &ipv6_hdr(skb)->daddr;
677
678 /* Perform checksum. */
679 switch (skb->ip_summed) {
680 case CHECKSUM_COMPLETE:
681 if (!csum_ipv6_magic(saddr, daddr, skb->len, IPPROTO_ICMPV6,
682 skb->csum))
683 break;
684 /* fall through */
685 case CHECKSUM_NONE:
686 skb->csum = ~csum_unfold(csum_ipv6_magic(saddr, daddr, skb->len,
687 IPPROTO_ICMPV6, 0));
688 if (__skb_checksum_complete(skb)) {
689 LIMIT_NETDEBUG(KERN_DEBUG "ICMPv6 checksum failed [%pI6 > %pI6]\n",
690 saddr, daddr);
691 goto discard_it;
692 }
693 }
694
695 if (!pskb_pull(skb, sizeof(*hdr)))
696 goto discard_it;
697
698 hdr = icmp6_hdr(skb);
699
700 type = hdr->icmp6_type;
701
702 ICMP6MSGIN_INC_STATS_BH(dev_net(dev), idev, type);
703
704 switch (type) {
705 case ICMPV6_ECHO_REQUEST:
706 icmpv6_echo_reply(skb);
707 break;
708
709 case ICMPV6_ECHO_REPLY:
710 /* we couldn't care less */
711 break;
712
713 case ICMPV6_PKT_TOOBIG:
714 /* BUGGG_FUTURE: if packet contains rthdr, we cannot update
715 standard destination cache. Seems, only "advanced"
716 destination cache will allow to solve this problem
717 --ANK (980726)
718 */
719 if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
720 goto discard_it;
721 hdr = icmp6_hdr(skb);
722 orig_hdr = (struct ipv6hdr *) (hdr + 1);
723 rt6_pmtu_discovery(&orig_hdr->daddr, &orig_hdr->saddr, dev,
724 ntohl(hdr->icmp6_mtu));
725
726 /*
727 * Drop through to notify
728 */
729
730 case ICMPV6_DEST_UNREACH:
731 case ICMPV6_TIME_EXCEED:
732 case ICMPV6_PARAMPROB:
733 icmpv6_notify(skb, type, hdr->icmp6_code, hdr->icmp6_mtu);
734 break;
735
736 case NDISC_ROUTER_SOLICITATION:
737 case NDISC_ROUTER_ADVERTISEMENT:
738 case NDISC_NEIGHBOUR_SOLICITATION:
739 case NDISC_NEIGHBOUR_ADVERTISEMENT:
740 case NDISC_REDIRECT:
741 ndisc_rcv(skb);
742 break;
743
744 case ICMPV6_MGM_QUERY:
745 igmp6_event_query(skb);
746 break;
747
748 case ICMPV6_MGM_REPORT:
749 igmp6_event_report(skb);
750 break;
751
752 case ICMPV6_MGM_REDUCTION:
753 case ICMPV6_NI_QUERY:
754 case ICMPV6_NI_REPLY:
755 case ICMPV6_MLD2_REPORT:
756 case ICMPV6_DHAAD_REQUEST:
757 case ICMPV6_DHAAD_REPLY:
758 case ICMPV6_MOBILE_PREFIX_SOL:
759 case ICMPV6_MOBILE_PREFIX_ADV:
760 break;
761
762 default:
763 LIMIT_NETDEBUG(KERN_DEBUG "icmpv6: msg of unknown type\n");
764
765 /* informational */
766 if (type & ICMPV6_INFOMSG_MASK)
767 break;
768
769 /*
770 * error of unknown type.
771 * must pass to upper level
772 */
773
774 icmpv6_notify(skb, type, hdr->icmp6_code, hdr->icmp6_mtu);
775 }
776
777 kfree_skb(skb);
778 return 0;
779
780discard_it:
781 ICMP6_INC_STATS_BH(dev_net(dev), idev, ICMP6_MIB_INERRORS);
782drop_no_count:
783 kfree_skb(skb);
784 return 0;
785}
786
787void icmpv6_flow_init(struct sock *sk, struct flowi6 *fl6,
788 u8 type,
789 const struct in6_addr *saddr,
790 const struct in6_addr *daddr,
791 int oif)
792{
793 memset(fl6, 0, sizeof(*fl6));
794 ipv6_addr_copy(&fl6->saddr, saddr);
795 ipv6_addr_copy(&fl6->daddr, daddr);
796 fl6->flowi6_proto = IPPROTO_ICMPV6;
797 fl6->fl6_icmp_type = type;
798 fl6->fl6_icmp_code = 0;
799 fl6->flowi6_oif = oif;
800 security_sk_classify_flow(sk, flowi6_to_flowi(fl6));
801}
802
803/*
804 * Special lock-class for __icmpv6_sk:
805 */
806static struct lock_class_key icmpv6_socket_sk_dst_lock_key;
807
808static int __net_init icmpv6_sk_init(struct net *net)
809{
810 struct sock *sk;
811 int err, i, j;
812
813 net->ipv6.icmp_sk =
814 kzalloc(nr_cpu_ids * sizeof(struct sock *), GFP_KERNEL);
815 if (net->ipv6.icmp_sk == NULL)
816 return -ENOMEM;
817
818 for_each_possible_cpu(i) {
819 err = inet_ctl_sock_create(&sk, PF_INET6,
820 SOCK_RAW, IPPROTO_ICMPV6, net);
821 if (err < 0) {
822 printk(KERN_ERR
823 "Failed to initialize the ICMP6 control socket "
824 "(err %d).\n",
825 err);
826 goto fail;
827 }
828
829 net->ipv6.icmp_sk[i] = sk;
830
831 /*
832 * Split off their lock-class, because sk->sk_dst_lock
833 * gets used from softirqs, which is safe for
834 * __icmpv6_sk (because those never get directly used
835 * via userspace syscalls), but unsafe for normal sockets.
836 */
837 lockdep_set_class(&sk->sk_dst_lock,
838 &icmpv6_socket_sk_dst_lock_key);
839
840 /* Enough space for 2 64K ICMP packets, including
841 * sk_buff struct overhead.
842 */
843 sk->sk_sndbuf =
844 (2 * ((64 * 1024) + sizeof(struct sk_buff)));
845 }
846 return 0;
847
848 fail:
849 for (j = 0; j < i; j++)
850 inet_ctl_sock_destroy(net->ipv6.icmp_sk[j]);
851 kfree(net->ipv6.icmp_sk);
852 return err;
853}
854
855static void __net_exit icmpv6_sk_exit(struct net *net)
856{
857 int i;
858
859 for_each_possible_cpu(i) {
860 inet_ctl_sock_destroy(net->ipv6.icmp_sk[i]);
861 }
862 kfree(net->ipv6.icmp_sk);
863}
864
865static struct pernet_operations icmpv6_sk_ops = {
866 .init = icmpv6_sk_init,
867 .exit = icmpv6_sk_exit,
868};
869
870int __init icmpv6_init(void)
871{
872 int err;
873
874 err = register_pernet_subsys(&icmpv6_sk_ops);
875 if (err < 0)
876 return err;
877
878 err = -EAGAIN;
879 if (inet6_add_protocol(&icmpv6_protocol, IPPROTO_ICMPV6) < 0)
880 goto fail;
881 return 0;
882
883fail:
884 printk(KERN_ERR "Failed to register ICMP6 protocol\n");
885 unregister_pernet_subsys(&icmpv6_sk_ops);
886 return err;
887}
888
889void icmpv6_cleanup(void)
890{
891 unregister_pernet_subsys(&icmpv6_sk_ops);
892 inet6_del_protocol(&icmpv6_protocol, IPPROTO_ICMPV6);
893}
894
895
896static const struct icmp6_err {
897 int err;
898 int fatal;
899} tab_unreach[] = {
900 { /* NOROUTE */
901 .err = ENETUNREACH,
902 .fatal = 0,
903 },
904 { /* ADM_PROHIBITED */
905 .err = EACCES,
906 .fatal = 1,
907 },
908 { /* Was NOT_NEIGHBOUR, now reserved */
909 .err = EHOSTUNREACH,
910 .fatal = 0,
911 },
912 { /* ADDR_UNREACH */
913 .err = EHOSTUNREACH,
914 .fatal = 0,
915 },
916 { /* PORT_UNREACH */
917 .err = ECONNREFUSED,
918 .fatal = 1,
919 },
920};
921
922int icmpv6_err_convert(u8 type, u8 code, int *err)
923{
924 int fatal = 0;
925
926 *err = EPROTO;
927
928 switch (type) {
929 case ICMPV6_DEST_UNREACH:
930 fatal = 1;
931 if (code <= ICMPV6_PORT_UNREACH) {
932 *err = tab_unreach[code].err;
933 fatal = tab_unreach[code].fatal;
934 }
935 break;
936
937 case ICMPV6_PKT_TOOBIG:
938 *err = EMSGSIZE;
939 break;
940
941 case ICMPV6_PARAMPROB:
942 *err = EPROTO;
943 fatal = 1;
944 break;
945
946 case ICMPV6_TIME_EXCEED:
947 *err = EHOSTUNREACH;
948 break;
949 }
950
951 return fatal;
952}
953
954EXPORT_SYMBOL(icmpv6_err_convert);
955
956#ifdef CONFIG_SYSCTL
957ctl_table ipv6_icmp_table_template[] = {
958 {
959 .procname = "ratelimit",
960 .data = &init_net.ipv6.sysctl.icmpv6_time,
961 .maxlen = sizeof(int),
962 .mode = 0644,
963 .proc_handler = proc_dointvec_ms_jiffies,
964 },
965 { },
966};
967
968struct ctl_table * __net_init ipv6_icmp_sysctl_init(struct net *net)
969{
970 struct ctl_table *table;
971
972 table = kmemdup(ipv6_icmp_table_template,
973 sizeof(ipv6_icmp_table_template),
974 GFP_KERNEL);
975
976 if (table)
977 table[0].data = &net->ipv6.sysctl.icmpv6_time;
978
979 return table;
980}
981#endif
982