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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#define pr_fmt(fmt) "IPv6: " fmt
33
34#include <linux/module.h>
35#include <linux/errno.h>
36#include <linux/types.h>
37#include <linux/socket.h>
38#include <linux/in.h>
39#include <linux/kernel.h>
40#include <linux/sockios.h>
41#include <linux/net.h>
42#include <linux/skbuff.h>
43#include <linux/init.h>
44#include <linux/netfilter.h>
45#include <linux/slab.h>
46
47#ifdef CONFIG_SYSCTL
48#include <linux/sysctl.h>
49#endif
50
51#include <linux/inet.h>
52#include <linux/netdevice.h>
53#include <linux/icmpv6.h>
54
55#include <net/ip.h>
56#include <net/sock.h>
57
58#include <net/ipv6.h>
59#include <net/ip6_checksum.h>
60#include <net/ping.h>
61#include <net/protocol.h>
62#include <net/raw.h>
63#include <net/rawv6.h>
64#include <net/transp_v6.h>
65#include <net/ip6_route.h>
66#include <net/addrconf.h>
67#include <net/icmp.h>
68#include <net/xfrm.h>
69#include <net/inet_common.h>
70#include <net/dsfield.h>
71#include <net/l3mdev.h>
72
73#include <asm/uaccess.h>
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 */
82static inline struct sock *icmpv6_sk(struct net *net)
83{
84 return net->ipv6.icmp_sk[smp_processor_id()];
85}
86
87static void icmpv6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
88 u8 type, u8 code, int offset, __be32 info)
89{
90 /* icmpv6_notify checks 8 bytes can be pulled, icmp6hdr is 8 bytes */
91 struct icmp6hdr *icmp6 = (struct icmp6hdr *) (skb->data + offset);
92 struct net *net = dev_net(skb->dev);
93
94 if (type == ICMPV6_PKT_TOOBIG)
95 ip6_update_pmtu(skb, net, info, 0, 0);
96 else if (type == NDISC_REDIRECT)
97 ip6_redirect(skb, net, skb->dev->ifindex, 0);
98
99 if (!(type & ICMPV6_INFOMSG_MASK))
100 if (icmp6->icmp6_type == ICMPV6_ECHO_REQUEST)
101 ping_err(skb, offset, info);
102}
103
104static int icmpv6_rcv(struct sk_buff *skb);
105
106static const struct inet6_protocol icmpv6_protocol = {
107 .handler = icmpv6_rcv,
108 .err_handler = icmpv6_err,
109 .flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
110};
111
112static __inline__ struct sock *icmpv6_xmit_lock(struct net *net)
113{
114 struct sock *sk;
115
116 local_bh_disable();
117
118 sk = icmpv6_sk(net);
119 if (unlikely(!spin_trylock(&sk->sk_lock.slock))) {
120 /* This can happen if the output path (f.e. SIT or
121 * ip6ip6 tunnel) signals dst_link_failure() for an
122 * outgoing ICMP6 packet.
123 */
124 local_bh_enable();
125 return NULL;
126 }
127 return sk;
128}
129
130static __inline__ void icmpv6_xmit_unlock(struct sock *sk)
131{
132 spin_unlock_bh(&sk->sk_lock.slock);
133}
134
135/*
136 * Figure out, may we reply to this packet with icmp error.
137 *
138 * We do not reply, if:
139 * - it was icmp error message.
140 * - it is truncated, so that it is known, that protocol is ICMPV6
141 * (i.e. in the middle of some exthdr)
142 *
143 * --ANK (980726)
144 */
145
146static bool is_ineligible(const struct sk_buff *skb)
147{
148 int ptr = (u8 *)(ipv6_hdr(skb) + 1) - skb->data;
149 int len = skb->len - ptr;
150 __u8 nexthdr = ipv6_hdr(skb)->nexthdr;
151 __be16 frag_off;
152
153 if (len < 0)
154 return true;
155
156 ptr = ipv6_skip_exthdr(skb, ptr, &nexthdr, &frag_off);
157 if (ptr < 0)
158 return false;
159 if (nexthdr == IPPROTO_ICMPV6) {
160 u8 _type, *tp;
161 tp = skb_header_pointer(skb,
162 ptr+offsetof(struct icmp6hdr, icmp6_type),
163 sizeof(_type), &_type);
164 if (!tp || !(*tp & ICMPV6_INFOMSG_MASK))
165 return true;
166 }
167 return false;
168}
169
170/*
171 * Check the ICMP output rate limit
172 */
173static bool icmpv6_xrlim_allow(struct sock *sk, u8 type,
174 struct flowi6 *fl6)
175{
176 struct net *net = sock_net(sk);
177 struct dst_entry *dst;
178 bool res = false;
179
180 /* Informational messages are not limited. */
181 if (type & ICMPV6_INFOMSG_MASK)
182 return true;
183
184 /* Do not limit pmtu discovery, it would break it. */
185 if (type == ICMPV6_PKT_TOOBIG)
186 return true;
187
188 /*
189 * Look up the output route.
190 * XXX: perhaps the expire for routing entries cloned by
191 * this lookup should be more aggressive (not longer than timeout).
192 */
193 dst = ip6_route_output(net, sk, fl6);
194 if (dst->error) {
195 IP6_INC_STATS(net, ip6_dst_idev(dst),
196 IPSTATS_MIB_OUTNOROUTES);
197 } else if (dst->dev && (dst->dev->flags&IFF_LOOPBACK)) {
198 res = true;
199 } else {
200 struct rt6_info *rt = (struct rt6_info *)dst;
201 int tmo = net->ipv6.sysctl.icmpv6_time;
202
203 /* Give more bandwidth to wider prefixes. */
204 if (rt->rt6i_dst.plen < 128)
205 tmo >>= ((128 - rt->rt6i_dst.plen)>>5);
206
207 if (icmp_global_allow()) {
208 struct inet_peer *peer;
209
210 peer = inet_getpeer_v6(net->ipv6.peers,
211 &fl6->daddr, 1);
212 res = inet_peer_xrlim_allow(peer, tmo);
213 if (peer)
214 inet_putpeer(peer);
215 }
216 }
217 dst_release(dst);
218 return res;
219}
220
221/*
222 * an inline helper for the "simple" if statement below
223 * checks if parameter problem report is caused by an
224 * unrecognized IPv6 option that has the Option Type
225 * highest-order two bits set to 10
226 */
227
228static bool opt_unrec(struct sk_buff *skb, __u32 offset)
229{
230 u8 _optval, *op;
231
232 offset += skb_network_offset(skb);
233 op = skb_header_pointer(skb, offset, sizeof(_optval), &_optval);
234 if (!op)
235 return true;
236 return (*op & 0xC0) == 0x80;
237}
238
239int icmpv6_push_pending_frames(struct sock *sk, struct flowi6 *fl6,
240 struct icmp6hdr *thdr, int len)
241{
242 struct sk_buff *skb;
243 struct icmp6hdr *icmp6h;
244 int err = 0;
245
246 skb = skb_peek(&sk->sk_write_queue);
247 if (!skb)
248 goto out;
249
250 icmp6h = icmp6_hdr(skb);
251 memcpy(icmp6h, thdr, sizeof(struct icmp6hdr));
252 icmp6h->icmp6_cksum = 0;
253
254 if (skb_queue_len(&sk->sk_write_queue) == 1) {
255 skb->csum = csum_partial(icmp6h,
256 sizeof(struct icmp6hdr), skb->csum);
257 icmp6h->icmp6_cksum = csum_ipv6_magic(&fl6->saddr,
258 &fl6->daddr,
259 len, fl6->flowi6_proto,
260 skb->csum);
261 } else {
262 __wsum tmp_csum = 0;
263
264 skb_queue_walk(&sk->sk_write_queue, skb) {
265 tmp_csum = csum_add(tmp_csum, skb->csum);
266 }
267
268 tmp_csum = csum_partial(icmp6h,
269 sizeof(struct icmp6hdr), tmp_csum);
270 icmp6h->icmp6_cksum = csum_ipv6_magic(&fl6->saddr,
271 &fl6->daddr,
272 len, fl6->flowi6_proto,
273 tmp_csum);
274 }
275 ip6_push_pending_frames(sk);
276out:
277 return err;
278}
279
280struct icmpv6_msg {
281 struct sk_buff *skb;
282 int offset;
283 uint8_t type;
284};
285
286static int icmpv6_getfrag(void *from, char *to, int offset, int len, int odd, struct sk_buff *skb)
287{
288 struct icmpv6_msg *msg = (struct icmpv6_msg *) from;
289 struct sk_buff *org_skb = msg->skb;
290 __wsum csum = 0;
291
292 csum = skb_copy_and_csum_bits(org_skb, msg->offset + offset,
293 to, len, csum);
294 skb->csum = csum_block_add(skb->csum, csum, odd);
295 if (!(msg->type & ICMPV6_INFOMSG_MASK))
296 nf_ct_attach(skb, org_skb);
297 return 0;
298}
299
300#if IS_ENABLED(CONFIG_IPV6_MIP6)
301static void mip6_addr_swap(struct sk_buff *skb)
302{
303 struct ipv6hdr *iph = ipv6_hdr(skb);
304 struct inet6_skb_parm *opt = IP6CB(skb);
305 struct ipv6_destopt_hao *hao;
306 struct in6_addr tmp;
307 int off;
308
309 if (opt->dsthao) {
310 off = ipv6_find_tlv(skb, opt->dsthao, IPV6_TLV_HAO);
311 if (likely(off >= 0)) {
312 hao = (struct ipv6_destopt_hao *)
313 (skb_network_header(skb) + off);
314 tmp = iph->saddr;
315 iph->saddr = hao->addr;
316 hao->addr = tmp;
317 }
318 }
319}
320#else
321static inline void mip6_addr_swap(struct sk_buff *skb) {}
322#endif
323
324static struct dst_entry *icmpv6_route_lookup(struct net *net,
325 struct sk_buff *skb,
326 struct sock *sk,
327 struct flowi6 *fl6)
328{
329 struct dst_entry *dst, *dst2;
330 struct flowi6 fl2;
331 int err;
332
333 err = ip6_dst_lookup(net, sk, &dst, fl6);
334 if (err)
335 return ERR_PTR(err);
336
337 /*
338 * We won't send icmp if the destination is known
339 * anycast.
340 */
341 if (ipv6_anycast_destination(dst, &fl6->daddr)) {
342 net_dbg_ratelimited("icmp6_send: acast source\n");
343 dst_release(dst);
344 return ERR_PTR(-EINVAL);
345 }
346
347 /* No need to clone since we're just using its address. */
348 dst2 = dst;
349
350 dst = xfrm_lookup(net, dst, flowi6_to_flowi(fl6), sk, 0);
351 if (!IS_ERR(dst)) {
352 if (dst != dst2)
353 return dst;
354 } else {
355 if (PTR_ERR(dst) == -EPERM)
356 dst = NULL;
357 else
358 return dst;
359 }
360
361 err = xfrm_decode_session_reverse(skb, flowi6_to_flowi(&fl2), AF_INET6);
362 if (err)
363 goto relookup_failed;
364
365 err = ip6_dst_lookup(net, sk, &dst2, &fl2);
366 if (err)
367 goto relookup_failed;
368
369 dst2 = xfrm_lookup(net, dst2, flowi6_to_flowi(&fl2), sk, XFRM_LOOKUP_ICMP);
370 if (!IS_ERR(dst2)) {
371 dst_release(dst);
372 dst = dst2;
373 } else {
374 err = PTR_ERR(dst2);
375 if (err == -EPERM) {
376 dst_release(dst);
377 return dst2;
378 } else
379 goto relookup_failed;
380 }
381
382relookup_failed:
383 if (dst)
384 return dst;
385 return ERR_PTR(err);
386}
387
388/*
389 * Send an ICMP message in response to a packet in error
390 */
391static void icmp6_send(struct sk_buff *skb, u8 type, u8 code, __u32 info)
392{
393 struct net *net = dev_net(skb->dev);
394 struct inet6_dev *idev = NULL;
395 struct ipv6hdr *hdr = ipv6_hdr(skb);
396 struct sock *sk;
397 struct ipv6_pinfo *np;
398 const struct in6_addr *saddr = NULL;
399 struct dst_entry *dst;
400 struct icmp6hdr tmp_hdr;
401 struct flowi6 fl6;
402 struct icmpv6_msg msg;
403 int iif = 0;
404 int addr_type = 0;
405 int len;
406 int hlimit;
407 int err = 0;
408 u32 mark = IP6_REPLY_MARK(net, skb->mark);
409
410 if ((u8 *)hdr < skb->head ||
411 (skb_network_header(skb) + sizeof(*hdr)) > skb_tail_pointer(skb))
412 return;
413
414 /*
415 * Make sure we respect the rules
416 * i.e. RFC 1885 2.4(e)
417 * Rule (e.1) is enforced by not using icmp6_send
418 * in any code that processes icmp errors.
419 */
420 addr_type = ipv6_addr_type(&hdr->daddr);
421
422 if (ipv6_chk_addr(net, &hdr->daddr, skb->dev, 0) ||
423 ipv6_chk_acast_addr_src(net, skb->dev, &hdr->daddr))
424 saddr = &hdr->daddr;
425
426 /*
427 * Dest addr check
428 */
429
430 if (addr_type & IPV6_ADDR_MULTICAST || skb->pkt_type != PACKET_HOST) {
431 if (type != ICMPV6_PKT_TOOBIG &&
432 !(type == ICMPV6_PARAMPROB &&
433 code == ICMPV6_UNK_OPTION &&
434 (opt_unrec(skb, info))))
435 return;
436
437 saddr = NULL;
438 }
439
440 addr_type = ipv6_addr_type(&hdr->saddr);
441
442 /*
443 * Source addr check
444 */
445
446 if (__ipv6_addr_needs_scope_id(addr_type))
447 iif = skb->dev->ifindex;
448 else
449 iif = l3mdev_master_ifindex(skb->dev);
450
451 /*
452 * Must not send error if the source does not uniquely
453 * identify a single node (RFC2463 Section 2.4).
454 * We check unspecified / multicast addresses here,
455 * and anycast addresses will be checked later.
456 */
457 if ((addr_type == IPV6_ADDR_ANY) || (addr_type & IPV6_ADDR_MULTICAST)) {
458 net_dbg_ratelimited("icmp6_send: addr_any/mcast source [%pI6c > %pI6c]\n",
459 &hdr->saddr, &hdr->daddr);
460 return;
461 }
462
463 /*
464 * Never answer to a ICMP packet.
465 */
466 if (is_ineligible(skb)) {
467 net_dbg_ratelimited("icmp6_send: no reply to icmp error [%pI6c > %pI6c]\n",
468 &hdr->saddr, &hdr->daddr);
469 return;
470 }
471
472 mip6_addr_swap(skb);
473
474 memset(&fl6, 0, sizeof(fl6));
475 fl6.flowi6_proto = IPPROTO_ICMPV6;
476 fl6.daddr = hdr->saddr;
477 if (saddr)
478 fl6.saddr = *saddr;
479 fl6.flowi6_mark = mark;
480 fl6.flowi6_oif = iif;
481 fl6.fl6_icmp_type = type;
482 fl6.fl6_icmp_code = code;
483 security_skb_classify_flow(skb, flowi6_to_flowi(&fl6));
484
485 sk = icmpv6_xmit_lock(net);
486 if (!sk)
487 return;
488 sk->sk_mark = mark;
489 np = inet6_sk(sk);
490
491 if (!icmpv6_xrlim_allow(sk, type, &fl6))
492 goto out;
493
494 tmp_hdr.icmp6_type = type;
495 tmp_hdr.icmp6_code = code;
496 tmp_hdr.icmp6_cksum = 0;
497 tmp_hdr.icmp6_pointer = htonl(info);
498
499 if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr))
500 fl6.flowi6_oif = np->mcast_oif;
501 else if (!fl6.flowi6_oif)
502 fl6.flowi6_oif = np->ucast_oif;
503
504 dst = icmpv6_route_lookup(net, skb, sk, &fl6);
505 if (IS_ERR(dst))
506 goto out;
507
508 hlimit = ip6_sk_dst_hoplimit(np, &fl6, dst);
509
510 msg.skb = skb;
511 msg.offset = skb_network_offset(skb);
512 msg.type = type;
513
514 len = skb->len - msg.offset;
515 len = min_t(unsigned int, len, IPV6_MIN_MTU - sizeof(struct ipv6hdr) - sizeof(struct icmp6hdr));
516 if (len < 0) {
517 net_dbg_ratelimited("icmp: len problem [%pI6c > %pI6c]\n",
518 &hdr->saddr, &hdr->daddr);
519 goto out_dst_release;
520 }
521
522 rcu_read_lock();
523 idev = __in6_dev_get(skb->dev);
524
525 err = ip6_append_data(sk, icmpv6_getfrag, &msg,
526 len + sizeof(struct icmp6hdr),
527 sizeof(struct icmp6hdr), hlimit,
528 np->tclass, NULL, &fl6, (struct rt6_info *)dst,
529 MSG_DONTWAIT, np->dontfrag);
530 if (err) {
531 ICMP6_INC_STATS(net, idev, ICMP6_MIB_OUTERRORS);
532 ip6_flush_pending_frames(sk);
533 } else {
534 err = icmpv6_push_pending_frames(sk, &fl6, &tmp_hdr,
535 len + sizeof(struct icmp6hdr));
536 }
537 rcu_read_unlock();
538out_dst_release:
539 dst_release(dst);
540out:
541 icmpv6_xmit_unlock(sk);
542}
543
544/* Slightly more convenient version of icmp6_send.
545 */
546void icmpv6_param_prob(struct sk_buff *skb, u8 code, int pos)
547{
548 icmp6_send(skb, ICMPV6_PARAMPROB, code, pos);
549 kfree_skb(skb);
550}
551
552static void icmpv6_echo_reply(struct sk_buff *skb)
553{
554 struct net *net = dev_net(skb->dev);
555 struct sock *sk;
556 struct inet6_dev *idev;
557 struct ipv6_pinfo *np;
558 const struct in6_addr *saddr = NULL;
559 struct icmp6hdr *icmph = icmp6_hdr(skb);
560 struct icmp6hdr tmp_hdr;
561 struct flowi6 fl6;
562 struct icmpv6_msg msg;
563 struct dst_entry *dst;
564 int err = 0;
565 int hlimit;
566 u8 tclass;
567 u32 mark = IP6_REPLY_MARK(net, skb->mark);
568
569 saddr = &ipv6_hdr(skb)->daddr;
570
571 if (!ipv6_unicast_destination(skb) &&
572 !(net->ipv6.sysctl.anycast_src_echo_reply &&
573 ipv6_anycast_destination(skb_dst(skb), saddr)))
574 saddr = NULL;
575
576 memcpy(&tmp_hdr, icmph, sizeof(tmp_hdr));
577 tmp_hdr.icmp6_type = ICMPV6_ECHO_REPLY;
578
579 memset(&fl6, 0, sizeof(fl6));
580 fl6.flowi6_proto = IPPROTO_ICMPV6;
581 fl6.daddr = ipv6_hdr(skb)->saddr;
582 if (saddr)
583 fl6.saddr = *saddr;
584 fl6.flowi6_oif = l3mdev_fib_oif(skb->dev);
585 fl6.fl6_icmp_type = ICMPV6_ECHO_REPLY;
586 fl6.flowi6_mark = mark;
587 security_skb_classify_flow(skb, flowi6_to_flowi(&fl6));
588
589 sk = icmpv6_xmit_lock(net);
590 if (!sk)
591 return;
592 sk->sk_mark = mark;
593 np = inet6_sk(sk);
594
595 if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr))
596 fl6.flowi6_oif = np->mcast_oif;
597 else if (!fl6.flowi6_oif)
598 fl6.flowi6_oif = np->ucast_oif;
599
600 err = ip6_dst_lookup(net, sk, &dst, &fl6);
601 if (err)
602 goto out;
603 dst = xfrm_lookup(net, dst, flowi6_to_flowi(&fl6), sk, 0);
604 if (IS_ERR(dst))
605 goto out;
606
607 hlimit = ip6_sk_dst_hoplimit(np, &fl6, dst);
608
609 idev = __in6_dev_get(skb->dev);
610
611 msg.skb = skb;
612 msg.offset = 0;
613 msg.type = ICMPV6_ECHO_REPLY;
614
615 tclass = ipv6_get_dsfield(ipv6_hdr(skb));
616 err = ip6_append_data(sk, icmpv6_getfrag, &msg, skb->len + sizeof(struct icmp6hdr),
617 sizeof(struct icmp6hdr), hlimit, tclass, NULL, &fl6,
618 (struct rt6_info *)dst, MSG_DONTWAIT,
619 np->dontfrag);
620
621 if (err) {
622 ICMP6_INC_STATS_BH(net, idev, ICMP6_MIB_OUTERRORS);
623 ip6_flush_pending_frames(sk);
624 } else {
625 err = icmpv6_push_pending_frames(sk, &fl6, &tmp_hdr,
626 skb->len + sizeof(struct icmp6hdr));
627 }
628 dst_release(dst);
629out:
630 icmpv6_xmit_unlock(sk);
631}
632
633void icmpv6_notify(struct sk_buff *skb, u8 type, u8 code, __be32 info)
634{
635 const struct inet6_protocol *ipprot;
636 int inner_offset;
637 __be16 frag_off;
638 u8 nexthdr;
639 struct net *net = dev_net(skb->dev);
640
641 if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
642 goto out;
643
644 nexthdr = ((struct ipv6hdr *)skb->data)->nexthdr;
645 if (ipv6_ext_hdr(nexthdr)) {
646 /* now skip over extension headers */
647 inner_offset = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr),
648 &nexthdr, &frag_off);
649 if (inner_offset < 0)
650 goto out;
651 } else {
652 inner_offset = sizeof(struct ipv6hdr);
653 }
654
655 /* Checkin header including 8 bytes of inner protocol header. */
656 if (!pskb_may_pull(skb, inner_offset+8))
657 goto out;
658
659 /* BUGGG_FUTURE: we should try to parse exthdrs in this packet.
660 Without this we will not able f.e. to make source routed
661 pmtu discovery.
662 Corresponding argument (opt) to notifiers is already added.
663 --ANK (980726)
664 */
665
666 ipprot = rcu_dereference(inet6_protos[nexthdr]);
667 if (ipprot && ipprot->err_handler)
668 ipprot->err_handler(skb, NULL, type, code, inner_offset, info);
669
670 raw6_icmp_error(skb, nexthdr, type, code, inner_offset, info);
671 return;
672
673out:
674 ICMP6_INC_STATS_BH(net, __in6_dev_get(skb->dev), ICMP6_MIB_INERRORS);
675}
676
677/*
678 * Handle icmp messages
679 */
680
681static int icmpv6_rcv(struct sk_buff *skb)
682{
683 struct net_device *dev = skb->dev;
684 struct inet6_dev *idev = __in6_dev_get(dev);
685 const struct in6_addr *saddr, *daddr;
686 struct icmp6hdr *hdr;
687 u8 type;
688 bool success = false;
689
690 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) {
691 struct sec_path *sp = skb_sec_path(skb);
692 int nh;
693
694 if (!(sp && sp->xvec[sp->len - 1]->props.flags &
695 XFRM_STATE_ICMP))
696 goto drop_no_count;
697
698 if (!pskb_may_pull(skb, sizeof(*hdr) + sizeof(struct ipv6hdr)))
699 goto drop_no_count;
700
701 nh = skb_network_offset(skb);
702 skb_set_network_header(skb, sizeof(*hdr));
703
704 if (!xfrm6_policy_check_reverse(NULL, XFRM_POLICY_IN, skb))
705 goto drop_no_count;
706
707 skb_set_network_header(skb, nh);
708 }
709
710 ICMP6_INC_STATS_BH(dev_net(dev), idev, ICMP6_MIB_INMSGS);
711
712 saddr = &ipv6_hdr(skb)->saddr;
713 daddr = &ipv6_hdr(skb)->daddr;
714
715 if (skb_checksum_validate(skb, IPPROTO_ICMPV6, ip6_compute_pseudo)) {
716 net_dbg_ratelimited("ICMPv6 checksum failed [%pI6c > %pI6c]\n",
717 saddr, daddr);
718 goto csum_error;
719 }
720
721 if (!pskb_pull(skb, sizeof(*hdr)))
722 goto discard_it;
723
724 hdr = icmp6_hdr(skb);
725
726 type = hdr->icmp6_type;
727
728 ICMP6MSGIN_INC_STATS_BH(dev_net(dev), idev, type);
729
730 switch (type) {
731 case ICMPV6_ECHO_REQUEST:
732 icmpv6_echo_reply(skb);
733 break;
734
735 case ICMPV6_ECHO_REPLY:
736 success = ping_rcv(skb);
737 break;
738
739 case ICMPV6_PKT_TOOBIG:
740 /* BUGGG_FUTURE: if packet contains rthdr, we cannot update
741 standard destination cache. Seems, only "advanced"
742 destination cache will allow to solve this problem
743 --ANK (980726)
744 */
745 if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
746 goto discard_it;
747 hdr = icmp6_hdr(skb);
748
749 /*
750 * Drop through to notify
751 */
752
753 case ICMPV6_DEST_UNREACH:
754 case ICMPV6_TIME_EXCEED:
755 case ICMPV6_PARAMPROB:
756 icmpv6_notify(skb, type, hdr->icmp6_code, hdr->icmp6_mtu);
757 break;
758
759 case NDISC_ROUTER_SOLICITATION:
760 case NDISC_ROUTER_ADVERTISEMENT:
761 case NDISC_NEIGHBOUR_SOLICITATION:
762 case NDISC_NEIGHBOUR_ADVERTISEMENT:
763 case NDISC_REDIRECT:
764 ndisc_rcv(skb);
765 break;
766
767 case ICMPV6_MGM_QUERY:
768 igmp6_event_query(skb);
769 break;
770
771 case ICMPV6_MGM_REPORT:
772 igmp6_event_report(skb);
773 break;
774
775 case ICMPV6_MGM_REDUCTION:
776 case ICMPV6_NI_QUERY:
777 case ICMPV6_NI_REPLY:
778 case ICMPV6_MLD2_REPORT:
779 case ICMPV6_DHAAD_REQUEST:
780 case ICMPV6_DHAAD_REPLY:
781 case ICMPV6_MOBILE_PREFIX_SOL:
782 case ICMPV6_MOBILE_PREFIX_ADV:
783 break;
784
785 default:
786 /* informational */
787 if (type & ICMPV6_INFOMSG_MASK)
788 break;
789
790 net_dbg_ratelimited("icmpv6: msg of unknown type [%pI6c > %pI6c]\n",
791 saddr, daddr);
792
793 /*
794 * error of unknown type.
795 * must pass to upper level
796 */
797
798 icmpv6_notify(skb, type, hdr->icmp6_code, hdr->icmp6_mtu);
799 }
800
801 /* until the v6 path can be better sorted assume failure and
802 * preserve the status quo behaviour for the rest of the paths to here
803 */
804 if (success)
805 consume_skb(skb);
806 else
807 kfree_skb(skb);
808
809 return 0;
810
811csum_error:
812 ICMP6_INC_STATS_BH(dev_net(dev), idev, ICMP6_MIB_CSUMERRORS);
813discard_it:
814 ICMP6_INC_STATS_BH(dev_net(dev), idev, ICMP6_MIB_INERRORS);
815drop_no_count:
816 kfree_skb(skb);
817 return 0;
818}
819
820void icmpv6_flow_init(struct sock *sk, struct flowi6 *fl6,
821 u8 type,
822 const struct in6_addr *saddr,
823 const struct in6_addr *daddr,
824 int oif)
825{
826 memset(fl6, 0, sizeof(*fl6));
827 fl6->saddr = *saddr;
828 fl6->daddr = *daddr;
829 fl6->flowi6_proto = IPPROTO_ICMPV6;
830 fl6->fl6_icmp_type = type;
831 fl6->fl6_icmp_code = 0;
832 fl6->flowi6_oif = oif;
833 security_sk_classify_flow(sk, flowi6_to_flowi(fl6));
834}
835
836static int __net_init icmpv6_sk_init(struct net *net)
837{
838 struct sock *sk;
839 int err, i, j;
840
841 net->ipv6.icmp_sk =
842 kzalloc(nr_cpu_ids * sizeof(struct sock *), GFP_KERNEL);
843 if (!net->ipv6.icmp_sk)
844 return -ENOMEM;
845
846 for_each_possible_cpu(i) {
847 err = inet_ctl_sock_create(&sk, PF_INET6,
848 SOCK_RAW, IPPROTO_ICMPV6, net);
849 if (err < 0) {
850 pr_err("Failed to initialize the ICMP6 control socket (err %d)\n",
851 err);
852 goto fail;
853 }
854
855 net->ipv6.icmp_sk[i] = sk;
856
857 /* Enough space for 2 64K ICMP packets, including
858 * sk_buff struct overhead.
859 */
860 sk->sk_sndbuf = 2 * SKB_TRUESIZE(64 * 1024);
861 }
862 return 0;
863
864 fail:
865 for (j = 0; j < i; j++)
866 inet_ctl_sock_destroy(net->ipv6.icmp_sk[j]);
867 kfree(net->ipv6.icmp_sk);
868 return err;
869}
870
871static void __net_exit icmpv6_sk_exit(struct net *net)
872{
873 int i;
874
875 for_each_possible_cpu(i) {
876 inet_ctl_sock_destroy(net->ipv6.icmp_sk[i]);
877 }
878 kfree(net->ipv6.icmp_sk);
879}
880
881static struct pernet_operations icmpv6_sk_ops = {
882 .init = icmpv6_sk_init,
883 .exit = icmpv6_sk_exit,
884};
885
886int __init icmpv6_init(void)
887{
888 int err;
889
890 err = register_pernet_subsys(&icmpv6_sk_ops);
891 if (err < 0)
892 return err;
893
894 err = -EAGAIN;
895 if (inet6_add_protocol(&icmpv6_protocol, IPPROTO_ICMPV6) < 0)
896 goto fail;
897
898 err = inet6_register_icmp_sender(icmp6_send);
899 if (err)
900 goto sender_reg_err;
901 return 0;
902
903sender_reg_err:
904 inet6_del_protocol(&icmpv6_protocol, IPPROTO_ICMPV6);
905fail:
906 pr_err("Failed to register ICMP6 protocol\n");
907 unregister_pernet_subsys(&icmpv6_sk_ops);
908 return err;
909}
910
911void icmpv6_cleanup(void)
912{
913 inet6_unregister_icmp_sender(icmp6_send);
914 unregister_pernet_subsys(&icmpv6_sk_ops);
915 inet6_del_protocol(&icmpv6_protocol, IPPROTO_ICMPV6);
916}
917
918
919static const struct icmp6_err {
920 int err;
921 int fatal;
922} tab_unreach[] = {
923 { /* NOROUTE */
924 .err = ENETUNREACH,
925 .fatal = 0,
926 },
927 { /* ADM_PROHIBITED */
928 .err = EACCES,
929 .fatal = 1,
930 },
931 { /* Was NOT_NEIGHBOUR, now reserved */
932 .err = EHOSTUNREACH,
933 .fatal = 0,
934 },
935 { /* ADDR_UNREACH */
936 .err = EHOSTUNREACH,
937 .fatal = 0,
938 },
939 { /* PORT_UNREACH */
940 .err = ECONNREFUSED,
941 .fatal = 1,
942 },
943 { /* POLICY_FAIL */
944 .err = EACCES,
945 .fatal = 1,
946 },
947 { /* REJECT_ROUTE */
948 .err = EACCES,
949 .fatal = 1,
950 },
951};
952
953int icmpv6_err_convert(u8 type, u8 code, int *err)
954{
955 int fatal = 0;
956
957 *err = EPROTO;
958
959 switch (type) {
960 case ICMPV6_DEST_UNREACH:
961 fatal = 1;
962 if (code < ARRAY_SIZE(tab_unreach)) {
963 *err = tab_unreach[code].err;
964 fatal = tab_unreach[code].fatal;
965 }
966 break;
967
968 case ICMPV6_PKT_TOOBIG:
969 *err = EMSGSIZE;
970 break;
971
972 case ICMPV6_PARAMPROB:
973 *err = EPROTO;
974 fatal = 1;
975 break;
976
977 case ICMPV6_TIME_EXCEED:
978 *err = EHOSTUNREACH;
979 break;
980 }
981
982 return fatal;
983}
984EXPORT_SYMBOL(icmpv6_err_convert);
985
986#ifdef CONFIG_SYSCTL
987static struct ctl_table ipv6_icmp_table_template[] = {
988 {
989 .procname = "ratelimit",
990 .data = &init_net.ipv6.sysctl.icmpv6_time,
991 .maxlen = sizeof(int),
992 .mode = 0644,
993 .proc_handler = proc_dointvec_ms_jiffies,
994 },
995 { },
996};
997
998struct ctl_table * __net_init ipv6_icmp_sysctl_init(struct net *net)
999{
1000 struct ctl_table *table;
1001
1002 table = kmemdup(ipv6_icmp_table_template,
1003 sizeof(ipv6_icmp_table_template),
1004 GFP_KERNEL);
1005
1006 if (table)
1007 table[0].data = &net->ipv6.sysctl.icmpv6_time;
1008
1009 return table;
1010}
1011#endif
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/seg6.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#include <net/dsfield.h>
68#include <net/l3mdev.h>
69
70#include <linux/uaccess.h>
71
72static DEFINE_PER_CPU(struct sock *, ipv6_icmp_sk);
73
74static int icmpv6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
75 u8 type, u8 code, int offset, __be32 info)
76{
77 /* icmpv6_notify checks 8 bytes can be pulled, icmp6hdr is 8 bytes */
78 struct icmp6hdr *icmp6 = (struct icmp6hdr *) (skb->data + offset);
79 struct net *net = dev_net(skb->dev);
80
81 if (type == ICMPV6_PKT_TOOBIG)
82 ip6_update_pmtu(skb, net, info, skb->dev->ifindex, 0, sock_net_uid(net, NULL));
83 else if (type == NDISC_REDIRECT)
84 ip6_redirect(skb, net, skb->dev->ifindex, 0,
85 sock_net_uid(net, NULL));
86
87 if (!(type & ICMPV6_INFOMSG_MASK))
88 if (icmp6->icmp6_type == ICMPV6_ECHO_REQUEST)
89 ping_err(skb, offset, ntohl(info));
90
91 return 0;
92}
93
94static int icmpv6_rcv(struct sk_buff *skb);
95
96static const struct inet6_protocol icmpv6_protocol = {
97 .handler = icmpv6_rcv,
98 .err_handler = icmpv6_err,
99 .flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
100};
101
102/* Called with BH disabled */
103static struct sock *icmpv6_xmit_lock(struct net *net)
104{
105 struct sock *sk;
106
107 sk = this_cpu_read(ipv6_icmp_sk);
108 if (unlikely(!spin_trylock(&sk->sk_lock.slock))) {
109 /* This can happen if the output path (f.e. SIT or
110 * ip6ip6 tunnel) signals dst_link_failure() for an
111 * outgoing ICMP6 packet.
112 */
113 return NULL;
114 }
115 sock_net_set(sk, net);
116 return sk;
117}
118
119static void icmpv6_xmit_unlock(struct sock *sk)
120{
121 sock_net_set(sk, &init_net);
122 spin_unlock(&sk->sk_lock.slock);
123}
124
125/*
126 * Figure out, may we reply to this packet with icmp error.
127 *
128 * We do not reply, if:
129 * - it was icmp error message.
130 * - it is truncated, so that it is known, that protocol is ICMPV6
131 * (i.e. in the middle of some exthdr)
132 *
133 * --ANK (980726)
134 */
135
136static bool is_ineligible(const struct sk_buff *skb)
137{
138 int ptr = (u8 *)(ipv6_hdr(skb) + 1) - skb->data;
139 int len = skb->len - ptr;
140 __u8 nexthdr = ipv6_hdr(skb)->nexthdr;
141 __be16 frag_off;
142
143 if (len < 0)
144 return true;
145
146 ptr = ipv6_skip_exthdr(skb, ptr, &nexthdr, &frag_off);
147 if (ptr < 0)
148 return false;
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
155 /* Based on RFC 8200, Section 4.5 Fragment Header, return
156 * false if this is a fragment packet with no icmp header info.
157 */
158 if (!tp && frag_off != 0)
159 return false;
160 else if (!tp || !(*tp & ICMPV6_INFOMSG_MASK))
161 return true;
162 }
163 return false;
164}
165
166static bool icmpv6_mask_allow(struct net *net, int type)
167{
168 if (type > ICMPV6_MSG_MAX)
169 return true;
170
171 /* Limit if icmp type is set in ratemask. */
172 if (!test_bit(type, net->ipv6.sysctl.icmpv6_ratemask))
173 return true;
174
175 return false;
176}
177
178static bool icmpv6_global_allow(struct net *net, int type)
179{
180 if (icmpv6_mask_allow(net, type))
181 return true;
182
183 if (icmp_global_allow())
184 return true;
185
186 return false;
187}
188
189/*
190 * Check the ICMP output rate limit
191 */
192static bool icmpv6_xrlim_allow(struct sock *sk, u8 type,
193 struct flowi6 *fl6)
194{
195 struct net *net = sock_net(sk);
196 struct dst_entry *dst;
197 bool res = false;
198
199 if (icmpv6_mask_allow(net, type))
200 return true;
201
202 /*
203 * Look up the output route.
204 * XXX: perhaps the expire for routing entries cloned by
205 * this lookup should be more aggressive (not longer than timeout).
206 */
207 dst = ip6_route_output(net, sk, fl6);
208 if (dst->error) {
209 IP6_INC_STATS(net, ip6_dst_idev(dst),
210 IPSTATS_MIB_OUTNOROUTES);
211 } else if (dst->dev && (dst->dev->flags&IFF_LOOPBACK)) {
212 res = true;
213 } else {
214 struct rt6_info *rt = (struct rt6_info *)dst;
215 int tmo = net->ipv6.sysctl.icmpv6_time;
216 struct inet_peer *peer;
217
218 /* Give more bandwidth to wider prefixes. */
219 if (rt->rt6i_dst.plen < 128)
220 tmo >>= ((128 - rt->rt6i_dst.plen)>>5);
221
222 peer = inet_getpeer_v6(net->ipv6.peers, &fl6->daddr, 1);
223 res = inet_peer_xrlim_allow(peer, tmo);
224 if (peer)
225 inet_putpeer(peer);
226 }
227 dst_release(dst);
228 return res;
229}
230
231static bool icmpv6_rt_has_prefsrc(struct sock *sk, u8 type,
232 struct flowi6 *fl6)
233{
234 struct net *net = sock_net(sk);
235 struct dst_entry *dst;
236 bool res = false;
237
238 dst = ip6_route_output(net, sk, fl6);
239 if (!dst->error) {
240 struct rt6_info *rt = (struct rt6_info *)dst;
241 struct in6_addr prefsrc;
242
243 rt6_get_prefsrc(rt, &prefsrc);
244 res = !ipv6_addr_any(&prefsrc);
245 }
246 dst_release(dst);
247 return res;
248}
249
250/*
251 * an inline helper for the "simple" if statement below
252 * checks if parameter problem report is caused by an
253 * unrecognized IPv6 option that has the Option Type
254 * highest-order two bits set to 10
255 */
256
257static bool opt_unrec(struct sk_buff *skb, __u32 offset)
258{
259 u8 _optval, *op;
260
261 offset += skb_network_offset(skb);
262 op = skb_header_pointer(skb, offset, sizeof(_optval), &_optval);
263 if (!op)
264 return true;
265 return (*op & 0xC0) == 0x80;
266}
267
268void icmpv6_push_pending_frames(struct sock *sk, struct flowi6 *fl6,
269 struct icmp6hdr *thdr, int len)
270{
271 struct sk_buff *skb;
272 struct icmp6hdr *icmp6h;
273
274 skb = skb_peek(&sk->sk_write_queue);
275 if (!skb)
276 return;
277
278 icmp6h = icmp6_hdr(skb);
279 memcpy(icmp6h, thdr, sizeof(struct icmp6hdr));
280 icmp6h->icmp6_cksum = 0;
281
282 if (skb_queue_len(&sk->sk_write_queue) == 1) {
283 skb->csum = csum_partial(icmp6h,
284 sizeof(struct icmp6hdr), skb->csum);
285 icmp6h->icmp6_cksum = csum_ipv6_magic(&fl6->saddr,
286 &fl6->daddr,
287 len, fl6->flowi6_proto,
288 skb->csum);
289 } else {
290 __wsum tmp_csum = 0;
291
292 skb_queue_walk(&sk->sk_write_queue, skb) {
293 tmp_csum = csum_add(tmp_csum, skb->csum);
294 }
295
296 tmp_csum = csum_partial(icmp6h,
297 sizeof(struct icmp6hdr), tmp_csum);
298 icmp6h->icmp6_cksum = csum_ipv6_magic(&fl6->saddr,
299 &fl6->daddr,
300 len, fl6->flowi6_proto,
301 tmp_csum);
302 }
303 ip6_push_pending_frames(sk);
304}
305
306struct icmpv6_msg {
307 struct sk_buff *skb;
308 int offset;
309 uint8_t type;
310};
311
312static int icmpv6_getfrag(void *from, char *to, int offset, int len, int odd, struct sk_buff *skb)
313{
314 struct icmpv6_msg *msg = (struct icmpv6_msg *) from;
315 struct sk_buff *org_skb = msg->skb;
316 __wsum csum;
317
318 csum = skb_copy_and_csum_bits(org_skb, msg->offset + offset,
319 to, len);
320 skb->csum = csum_block_add(skb->csum, csum, odd);
321 if (!(msg->type & ICMPV6_INFOMSG_MASK))
322 nf_ct_attach(skb, org_skb);
323 return 0;
324}
325
326#if IS_ENABLED(CONFIG_IPV6_MIP6)
327static void mip6_addr_swap(struct sk_buff *skb, const struct inet6_skb_parm *opt)
328{
329 struct ipv6hdr *iph = ipv6_hdr(skb);
330 struct ipv6_destopt_hao *hao;
331 struct in6_addr tmp;
332 int off;
333
334 if (opt->dsthao) {
335 off = ipv6_find_tlv(skb, opt->dsthao, IPV6_TLV_HAO);
336 if (likely(off >= 0)) {
337 hao = (struct ipv6_destopt_hao *)
338 (skb_network_header(skb) + off);
339 tmp = iph->saddr;
340 iph->saddr = hao->addr;
341 hao->addr = tmp;
342 }
343 }
344}
345#else
346static inline void mip6_addr_swap(struct sk_buff *skb, const struct inet6_skb_parm *opt) {}
347#endif
348
349static struct dst_entry *icmpv6_route_lookup(struct net *net,
350 struct sk_buff *skb,
351 struct sock *sk,
352 struct flowi6 *fl6)
353{
354 struct dst_entry *dst, *dst2;
355 struct flowi6 fl2;
356 int err;
357
358 err = ip6_dst_lookup(net, sk, &dst, fl6);
359 if (err)
360 return ERR_PTR(err);
361
362 /*
363 * We won't send icmp if the destination is known
364 * anycast.
365 */
366 if (ipv6_anycast_destination(dst, &fl6->daddr)) {
367 net_dbg_ratelimited("icmp6_send: acast source\n");
368 dst_release(dst);
369 return ERR_PTR(-EINVAL);
370 }
371
372 /* No need to clone since we're just using its address. */
373 dst2 = dst;
374
375 dst = xfrm_lookup(net, dst, flowi6_to_flowi(fl6), sk, 0);
376 if (!IS_ERR(dst)) {
377 if (dst != dst2)
378 return dst;
379 } else {
380 if (PTR_ERR(dst) == -EPERM)
381 dst = NULL;
382 else
383 return dst;
384 }
385
386 err = xfrm_decode_session_reverse(skb, flowi6_to_flowi(&fl2), AF_INET6);
387 if (err)
388 goto relookup_failed;
389
390 err = ip6_dst_lookup(net, sk, &dst2, &fl2);
391 if (err)
392 goto relookup_failed;
393
394 dst2 = xfrm_lookup(net, dst2, flowi6_to_flowi(&fl2), sk, XFRM_LOOKUP_ICMP);
395 if (!IS_ERR(dst2)) {
396 dst_release(dst);
397 dst = dst2;
398 } else {
399 err = PTR_ERR(dst2);
400 if (err == -EPERM) {
401 dst_release(dst);
402 return dst2;
403 } else
404 goto relookup_failed;
405 }
406
407relookup_failed:
408 if (dst)
409 return dst;
410 return ERR_PTR(err);
411}
412
413static struct net_device *icmp6_dev(const struct sk_buff *skb)
414{
415 struct net_device *dev = skb->dev;
416
417 /* for local traffic to local address, skb dev is the loopback
418 * device. Check if there is a dst attached to the skb and if so
419 * get the real device index. Same is needed for replies to a link
420 * local address on a device enslaved to an L3 master device
421 */
422 if (unlikely(dev->ifindex == LOOPBACK_IFINDEX || netif_is_l3_master(skb->dev))) {
423 const struct rt6_info *rt6 = skb_rt6_info(skb);
424
425 if (rt6)
426 dev = rt6->rt6i_idev->dev;
427 }
428
429 return dev;
430}
431
432static int icmp6_iif(const struct sk_buff *skb)
433{
434 return icmp6_dev(skb)->ifindex;
435}
436
437/*
438 * Send an ICMP message in response to a packet in error
439 */
440void icmp6_send(struct sk_buff *skb, u8 type, u8 code, __u32 info,
441 const struct in6_addr *force_saddr,
442 const struct inet6_skb_parm *parm)
443{
444 struct inet6_dev *idev = NULL;
445 struct ipv6hdr *hdr = ipv6_hdr(skb);
446 struct sock *sk;
447 struct net *net;
448 struct ipv6_pinfo *np;
449 const struct in6_addr *saddr = NULL;
450 struct dst_entry *dst;
451 struct icmp6hdr tmp_hdr;
452 struct flowi6 fl6;
453 struct icmpv6_msg msg;
454 struct ipcm6_cookie ipc6;
455 int iif = 0;
456 int addr_type = 0;
457 int len;
458 u32 mark;
459
460 if ((u8 *)hdr < skb->head ||
461 (skb_network_header(skb) + sizeof(*hdr)) > skb_tail_pointer(skb))
462 return;
463
464 if (!skb->dev)
465 return;
466 net = dev_net(skb->dev);
467 mark = IP6_REPLY_MARK(net, skb->mark);
468 /*
469 * Make sure we respect the rules
470 * i.e. RFC 1885 2.4(e)
471 * Rule (e.1) is enforced by not using icmp6_send
472 * in any code that processes icmp errors.
473 */
474 addr_type = ipv6_addr_type(&hdr->daddr);
475
476 if (ipv6_chk_addr(net, &hdr->daddr, skb->dev, 0) ||
477 ipv6_chk_acast_addr_src(net, skb->dev, &hdr->daddr))
478 saddr = &hdr->daddr;
479
480 /*
481 * Dest addr check
482 */
483
484 if (addr_type & IPV6_ADDR_MULTICAST || skb->pkt_type != PACKET_HOST) {
485 if (type != ICMPV6_PKT_TOOBIG &&
486 !(type == ICMPV6_PARAMPROB &&
487 code == ICMPV6_UNK_OPTION &&
488 (opt_unrec(skb, info))))
489 return;
490
491 saddr = NULL;
492 }
493
494 addr_type = ipv6_addr_type(&hdr->saddr);
495
496 /*
497 * Source addr check
498 */
499
500 if (__ipv6_addr_needs_scope_id(addr_type)) {
501 iif = icmp6_iif(skb);
502 } else {
503 /*
504 * The source device is used for looking up which routing table
505 * to use for sending an ICMP error.
506 */
507 iif = l3mdev_master_ifindex(skb->dev);
508 }
509
510 /*
511 * Must not send error if the source does not uniquely
512 * identify a single node (RFC2463 Section 2.4).
513 * We check unspecified / multicast addresses here,
514 * and anycast addresses will be checked later.
515 */
516 if ((addr_type == IPV6_ADDR_ANY) || (addr_type & IPV6_ADDR_MULTICAST)) {
517 net_dbg_ratelimited("icmp6_send: addr_any/mcast source [%pI6c > %pI6c]\n",
518 &hdr->saddr, &hdr->daddr);
519 return;
520 }
521
522 /*
523 * Never answer to a ICMP packet.
524 */
525 if (is_ineligible(skb)) {
526 net_dbg_ratelimited("icmp6_send: no reply to icmp error [%pI6c > %pI6c]\n",
527 &hdr->saddr, &hdr->daddr);
528 return;
529 }
530
531 /* Needed by both icmp_global_allow and icmpv6_xmit_lock */
532 local_bh_disable();
533
534 /* Check global sysctl_icmp_msgs_per_sec ratelimit */
535 if (!(skb->dev->flags & IFF_LOOPBACK) && !icmpv6_global_allow(net, type))
536 goto out_bh_enable;
537
538 mip6_addr_swap(skb, parm);
539
540 sk = icmpv6_xmit_lock(net);
541 if (!sk)
542 goto out_bh_enable;
543
544 memset(&fl6, 0, sizeof(fl6));
545 fl6.flowi6_proto = IPPROTO_ICMPV6;
546 fl6.daddr = hdr->saddr;
547 if (force_saddr)
548 saddr = force_saddr;
549 if (saddr) {
550 fl6.saddr = *saddr;
551 } else if (!icmpv6_rt_has_prefsrc(sk, type, &fl6)) {
552 /* select a more meaningful saddr from input if */
553 struct net_device *in_netdev;
554
555 in_netdev = dev_get_by_index(net, parm->iif);
556 if (in_netdev) {
557 ipv6_dev_get_saddr(net, in_netdev, &fl6.daddr,
558 inet6_sk(sk)->srcprefs,
559 &fl6.saddr);
560 dev_put(in_netdev);
561 }
562 }
563 fl6.flowi6_mark = mark;
564 fl6.flowi6_oif = iif;
565 fl6.fl6_icmp_type = type;
566 fl6.fl6_icmp_code = code;
567 fl6.flowi6_uid = sock_net_uid(net, NULL);
568 fl6.mp_hash = rt6_multipath_hash(net, &fl6, skb, NULL);
569 security_skb_classify_flow(skb, flowi6_to_flowi_common(&fl6));
570
571 np = inet6_sk(sk);
572
573 if (!icmpv6_xrlim_allow(sk, type, &fl6))
574 goto out;
575
576 tmp_hdr.icmp6_type = type;
577 tmp_hdr.icmp6_code = code;
578 tmp_hdr.icmp6_cksum = 0;
579 tmp_hdr.icmp6_pointer = htonl(info);
580
581 if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr))
582 fl6.flowi6_oif = np->mcast_oif;
583 else if (!fl6.flowi6_oif)
584 fl6.flowi6_oif = np->ucast_oif;
585
586 ipcm6_init_sk(&ipc6, np);
587 ipc6.sockc.mark = mark;
588 fl6.flowlabel = ip6_make_flowinfo(ipc6.tclass, fl6.flowlabel);
589
590 dst = icmpv6_route_lookup(net, skb, sk, &fl6);
591 if (IS_ERR(dst))
592 goto out;
593
594 ipc6.hlimit = ip6_sk_dst_hoplimit(np, &fl6, dst);
595
596 msg.skb = skb;
597 msg.offset = skb_network_offset(skb);
598 msg.type = type;
599
600 len = skb->len - msg.offset;
601 len = min_t(unsigned int, len, IPV6_MIN_MTU - sizeof(struct ipv6hdr) - sizeof(struct icmp6hdr));
602 if (len < 0) {
603 net_dbg_ratelimited("icmp: len problem [%pI6c > %pI6c]\n",
604 &hdr->saddr, &hdr->daddr);
605 goto out_dst_release;
606 }
607
608 rcu_read_lock();
609 idev = __in6_dev_get(skb->dev);
610
611 if (ip6_append_data(sk, icmpv6_getfrag, &msg,
612 len + sizeof(struct icmp6hdr),
613 sizeof(struct icmp6hdr),
614 &ipc6, &fl6, (struct rt6_info *)dst,
615 MSG_DONTWAIT)) {
616 ICMP6_INC_STATS(net, idev, ICMP6_MIB_OUTERRORS);
617 ip6_flush_pending_frames(sk);
618 } else {
619 icmpv6_push_pending_frames(sk, &fl6, &tmp_hdr,
620 len + sizeof(struct icmp6hdr));
621 }
622 rcu_read_unlock();
623out_dst_release:
624 dst_release(dst);
625out:
626 icmpv6_xmit_unlock(sk);
627out_bh_enable:
628 local_bh_enable();
629}
630EXPORT_SYMBOL(icmp6_send);
631
632/* Slightly more convenient version of icmp6_send with drop reasons.
633 */
634void icmpv6_param_prob_reason(struct sk_buff *skb, u8 code, int pos,
635 enum skb_drop_reason reason)
636{
637 icmp6_send(skb, ICMPV6_PARAMPROB, code, pos, NULL, IP6CB(skb));
638 kfree_skb_reason(skb, reason);
639}
640
641/* Generate icmpv6 with type/code ICMPV6_DEST_UNREACH/ICMPV6_ADDR_UNREACH
642 * if sufficient data bytes are available
643 * @nhs is the size of the tunnel header(s) :
644 * Either an IPv4 header for SIT encap
645 * an IPv4 header + GRE header for GRE encap
646 */
647int ip6_err_gen_icmpv6_unreach(struct sk_buff *skb, int nhs, int type,
648 unsigned int data_len)
649{
650 struct in6_addr temp_saddr;
651 struct rt6_info *rt;
652 struct sk_buff *skb2;
653 u32 info = 0;
654
655 if (!pskb_may_pull(skb, nhs + sizeof(struct ipv6hdr) + 8))
656 return 1;
657
658 /* RFC 4884 (partial) support for ICMP extensions */
659 if (data_len < 128 || (data_len & 7) || skb->len < data_len)
660 data_len = 0;
661
662 skb2 = data_len ? skb_copy(skb, GFP_ATOMIC) : skb_clone(skb, GFP_ATOMIC);
663
664 if (!skb2)
665 return 1;
666
667 skb_dst_drop(skb2);
668 skb_pull(skb2, nhs);
669 skb_reset_network_header(skb2);
670
671 rt = rt6_lookup(dev_net(skb->dev), &ipv6_hdr(skb2)->saddr, NULL, 0,
672 skb, 0);
673
674 if (rt && rt->dst.dev)
675 skb2->dev = rt->dst.dev;
676
677 ipv6_addr_set_v4mapped(ip_hdr(skb)->saddr, &temp_saddr);
678
679 if (data_len) {
680 /* RFC 4884 (partial) support :
681 * insert 0 padding at the end, before the extensions
682 */
683 __skb_push(skb2, nhs);
684 skb_reset_network_header(skb2);
685 memmove(skb2->data, skb2->data + nhs, data_len - nhs);
686 memset(skb2->data + data_len - nhs, 0, nhs);
687 /* RFC 4884 4.5 : Length is measured in 64-bit words,
688 * and stored in reserved[0]
689 */
690 info = (data_len/8) << 24;
691 }
692 if (type == ICMP_TIME_EXCEEDED)
693 icmp6_send(skb2, ICMPV6_TIME_EXCEED, ICMPV6_EXC_HOPLIMIT,
694 info, &temp_saddr, IP6CB(skb2));
695 else
696 icmp6_send(skb2, ICMPV6_DEST_UNREACH, ICMPV6_ADDR_UNREACH,
697 info, &temp_saddr, IP6CB(skb2));
698 if (rt)
699 ip6_rt_put(rt);
700
701 kfree_skb(skb2);
702
703 return 0;
704}
705EXPORT_SYMBOL(ip6_err_gen_icmpv6_unreach);
706
707static void icmpv6_echo_reply(struct sk_buff *skb)
708{
709 struct net *net = dev_net(skb->dev);
710 struct sock *sk;
711 struct inet6_dev *idev;
712 struct ipv6_pinfo *np;
713 const struct in6_addr *saddr = NULL;
714 struct icmp6hdr *icmph = icmp6_hdr(skb);
715 struct icmp6hdr tmp_hdr;
716 struct flowi6 fl6;
717 struct icmpv6_msg msg;
718 struct dst_entry *dst;
719 struct ipcm6_cookie ipc6;
720 u32 mark = IP6_REPLY_MARK(net, skb->mark);
721 bool acast;
722 u8 type;
723
724 if (ipv6_addr_is_multicast(&ipv6_hdr(skb)->daddr) &&
725 net->ipv6.sysctl.icmpv6_echo_ignore_multicast)
726 return;
727
728 saddr = &ipv6_hdr(skb)->daddr;
729
730 acast = ipv6_anycast_destination(skb_dst(skb), saddr);
731 if (acast && net->ipv6.sysctl.icmpv6_echo_ignore_anycast)
732 return;
733
734 if (!ipv6_unicast_destination(skb) &&
735 !(net->ipv6.sysctl.anycast_src_echo_reply && acast))
736 saddr = NULL;
737
738 if (icmph->icmp6_type == ICMPV6_EXT_ECHO_REQUEST)
739 type = ICMPV6_EXT_ECHO_REPLY;
740 else
741 type = ICMPV6_ECHO_REPLY;
742
743 memcpy(&tmp_hdr, icmph, sizeof(tmp_hdr));
744 tmp_hdr.icmp6_type = type;
745
746 memset(&fl6, 0, sizeof(fl6));
747 if (net->ipv6.sysctl.flowlabel_reflect & FLOWLABEL_REFLECT_ICMPV6_ECHO_REPLIES)
748 fl6.flowlabel = ip6_flowlabel(ipv6_hdr(skb));
749
750 fl6.flowi6_proto = IPPROTO_ICMPV6;
751 fl6.daddr = ipv6_hdr(skb)->saddr;
752 if (saddr)
753 fl6.saddr = *saddr;
754 fl6.flowi6_oif = icmp6_iif(skb);
755 fl6.fl6_icmp_type = type;
756 fl6.flowi6_mark = mark;
757 fl6.flowi6_uid = sock_net_uid(net, NULL);
758 security_skb_classify_flow(skb, flowi6_to_flowi_common(&fl6));
759
760 local_bh_disable();
761 sk = icmpv6_xmit_lock(net);
762 if (!sk)
763 goto out_bh_enable;
764 np = inet6_sk(sk);
765
766 if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr))
767 fl6.flowi6_oif = np->mcast_oif;
768 else if (!fl6.flowi6_oif)
769 fl6.flowi6_oif = np->ucast_oif;
770
771 if (ip6_dst_lookup(net, sk, &dst, &fl6))
772 goto out;
773 dst = xfrm_lookup(net, dst, flowi6_to_flowi(&fl6), sk, 0);
774 if (IS_ERR(dst))
775 goto out;
776
777 /* Check the ratelimit */
778 if ((!(skb->dev->flags & IFF_LOOPBACK) && !icmpv6_global_allow(net, ICMPV6_ECHO_REPLY)) ||
779 !icmpv6_xrlim_allow(sk, ICMPV6_ECHO_REPLY, &fl6))
780 goto out_dst_release;
781
782 idev = __in6_dev_get(skb->dev);
783
784 msg.skb = skb;
785 msg.offset = 0;
786 msg.type = type;
787
788 ipcm6_init_sk(&ipc6, np);
789 ipc6.hlimit = ip6_sk_dst_hoplimit(np, &fl6, dst);
790 ipc6.tclass = ipv6_get_dsfield(ipv6_hdr(skb));
791 ipc6.sockc.mark = mark;
792
793 if (icmph->icmp6_type == ICMPV6_EXT_ECHO_REQUEST)
794 if (!icmp_build_probe(skb, (struct icmphdr *)&tmp_hdr))
795 goto out_dst_release;
796
797 if (ip6_append_data(sk, icmpv6_getfrag, &msg,
798 skb->len + sizeof(struct icmp6hdr),
799 sizeof(struct icmp6hdr), &ipc6, &fl6,
800 (struct rt6_info *)dst, MSG_DONTWAIT)) {
801 __ICMP6_INC_STATS(net, idev, ICMP6_MIB_OUTERRORS);
802 ip6_flush_pending_frames(sk);
803 } else {
804 icmpv6_push_pending_frames(sk, &fl6, &tmp_hdr,
805 skb->len + sizeof(struct icmp6hdr));
806 }
807out_dst_release:
808 dst_release(dst);
809out:
810 icmpv6_xmit_unlock(sk);
811out_bh_enable:
812 local_bh_enable();
813}
814
815void icmpv6_notify(struct sk_buff *skb, u8 type, u8 code, __be32 info)
816{
817 struct inet6_skb_parm *opt = IP6CB(skb);
818 const struct inet6_protocol *ipprot;
819 int inner_offset;
820 __be16 frag_off;
821 u8 nexthdr;
822 struct net *net = dev_net(skb->dev);
823
824 if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
825 goto out;
826
827 seg6_icmp_srh(skb, opt);
828
829 nexthdr = ((struct ipv6hdr *)skb->data)->nexthdr;
830 if (ipv6_ext_hdr(nexthdr)) {
831 /* now skip over extension headers */
832 inner_offset = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr),
833 &nexthdr, &frag_off);
834 if (inner_offset < 0)
835 goto out;
836 } else {
837 inner_offset = sizeof(struct ipv6hdr);
838 }
839
840 /* Checkin header including 8 bytes of inner protocol header. */
841 if (!pskb_may_pull(skb, inner_offset+8))
842 goto out;
843
844 /* BUGGG_FUTURE: we should try to parse exthdrs in this packet.
845 Without this we will not able f.e. to make source routed
846 pmtu discovery.
847 Corresponding argument (opt) to notifiers is already added.
848 --ANK (980726)
849 */
850
851 ipprot = rcu_dereference(inet6_protos[nexthdr]);
852 if (ipprot && ipprot->err_handler)
853 ipprot->err_handler(skb, opt, type, code, inner_offset, info);
854
855 raw6_icmp_error(skb, nexthdr, type, code, inner_offset, info);
856 return;
857
858out:
859 __ICMP6_INC_STATS(net, __in6_dev_get(skb->dev), ICMP6_MIB_INERRORS);
860}
861
862/*
863 * Handle icmp messages
864 */
865
866static int icmpv6_rcv(struct sk_buff *skb)
867{
868 enum skb_drop_reason reason = SKB_DROP_REASON_NOT_SPECIFIED;
869 struct net *net = dev_net(skb->dev);
870 struct net_device *dev = icmp6_dev(skb);
871 struct inet6_dev *idev = __in6_dev_get(dev);
872 const struct in6_addr *saddr, *daddr;
873 struct icmp6hdr *hdr;
874 u8 type;
875
876 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) {
877 struct sec_path *sp = skb_sec_path(skb);
878 int nh;
879
880 if (!(sp && sp->xvec[sp->len - 1]->props.flags &
881 XFRM_STATE_ICMP)) {
882 reason = SKB_DROP_REASON_XFRM_POLICY;
883 goto drop_no_count;
884 }
885
886 if (!pskb_may_pull(skb, sizeof(*hdr) + sizeof(struct ipv6hdr)))
887 goto drop_no_count;
888
889 nh = skb_network_offset(skb);
890 skb_set_network_header(skb, sizeof(*hdr));
891
892 if (!xfrm6_policy_check_reverse(NULL, XFRM_POLICY_IN,
893 skb)) {
894 reason = SKB_DROP_REASON_XFRM_POLICY;
895 goto drop_no_count;
896 }
897
898 skb_set_network_header(skb, nh);
899 }
900
901 __ICMP6_INC_STATS(dev_net(dev), idev, ICMP6_MIB_INMSGS);
902
903 saddr = &ipv6_hdr(skb)->saddr;
904 daddr = &ipv6_hdr(skb)->daddr;
905
906 if (skb_checksum_validate(skb, IPPROTO_ICMPV6, ip6_compute_pseudo)) {
907 net_dbg_ratelimited("ICMPv6 checksum failed [%pI6c > %pI6c]\n",
908 saddr, daddr);
909 goto csum_error;
910 }
911
912 if (!pskb_pull(skb, sizeof(*hdr)))
913 goto discard_it;
914
915 hdr = icmp6_hdr(skb);
916
917 type = hdr->icmp6_type;
918
919 ICMP6MSGIN_INC_STATS(dev_net(dev), idev, type);
920
921 switch (type) {
922 case ICMPV6_ECHO_REQUEST:
923 if (!net->ipv6.sysctl.icmpv6_echo_ignore_all)
924 icmpv6_echo_reply(skb);
925 break;
926 case ICMPV6_EXT_ECHO_REQUEST:
927 if (!net->ipv6.sysctl.icmpv6_echo_ignore_all &&
928 READ_ONCE(net->ipv4.sysctl_icmp_echo_enable_probe))
929 icmpv6_echo_reply(skb);
930 break;
931
932 case ICMPV6_ECHO_REPLY:
933 reason = ping_rcv(skb);
934 break;
935
936 case ICMPV6_EXT_ECHO_REPLY:
937 reason = ping_rcv(skb);
938 break;
939
940 case ICMPV6_PKT_TOOBIG:
941 /* BUGGG_FUTURE: if packet contains rthdr, we cannot update
942 standard destination cache. Seems, only "advanced"
943 destination cache will allow to solve this problem
944 --ANK (980726)
945 */
946 if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
947 goto discard_it;
948 hdr = icmp6_hdr(skb);
949
950 /* to notify */
951 fallthrough;
952 case ICMPV6_DEST_UNREACH:
953 case ICMPV6_TIME_EXCEED:
954 case ICMPV6_PARAMPROB:
955 icmpv6_notify(skb, type, hdr->icmp6_code, hdr->icmp6_mtu);
956 break;
957
958 case NDISC_ROUTER_SOLICITATION:
959 case NDISC_ROUTER_ADVERTISEMENT:
960 case NDISC_NEIGHBOUR_SOLICITATION:
961 case NDISC_NEIGHBOUR_ADVERTISEMENT:
962 case NDISC_REDIRECT:
963 ndisc_rcv(skb);
964 break;
965
966 case ICMPV6_MGM_QUERY:
967 igmp6_event_query(skb);
968 return 0;
969
970 case ICMPV6_MGM_REPORT:
971 igmp6_event_report(skb);
972 return 0;
973
974 case ICMPV6_MGM_REDUCTION:
975 case ICMPV6_NI_QUERY:
976 case ICMPV6_NI_REPLY:
977 case ICMPV6_MLD2_REPORT:
978 case ICMPV6_DHAAD_REQUEST:
979 case ICMPV6_DHAAD_REPLY:
980 case ICMPV6_MOBILE_PREFIX_SOL:
981 case ICMPV6_MOBILE_PREFIX_ADV:
982 break;
983
984 default:
985 /* informational */
986 if (type & ICMPV6_INFOMSG_MASK)
987 break;
988
989 net_dbg_ratelimited("icmpv6: msg of unknown type [%pI6c > %pI6c]\n",
990 saddr, daddr);
991
992 /*
993 * error of unknown type.
994 * must pass to upper level
995 */
996
997 icmpv6_notify(skb, type, hdr->icmp6_code, hdr->icmp6_mtu);
998 }
999
1000 /* until the v6 path can be better sorted assume failure and
1001 * preserve the status quo behaviour for the rest of the paths to here
1002 */
1003 if (reason)
1004 kfree_skb_reason(skb, reason);
1005 else
1006 consume_skb(skb);
1007
1008 return 0;
1009
1010csum_error:
1011 reason = SKB_DROP_REASON_ICMP_CSUM;
1012 __ICMP6_INC_STATS(dev_net(dev), idev, ICMP6_MIB_CSUMERRORS);
1013discard_it:
1014 __ICMP6_INC_STATS(dev_net(dev), idev, ICMP6_MIB_INERRORS);
1015drop_no_count:
1016 kfree_skb_reason(skb, reason);
1017 return 0;
1018}
1019
1020void icmpv6_flow_init(struct sock *sk, struct flowi6 *fl6,
1021 u8 type,
1022 const struct in6_addr *saddr,
1023 const struct in6_addr *daddr,
1024 int oif)
1025{
1026 memset(fl6, 0, sizeof(*fl6));
1027 fl6->saddr = *saddr;
1028 fl6->daddr = *daddr;
1029 fl6->flowi6_proto = IPPROTO_ICMPV6;
1030 fl6->fl6_icmp_type = type;
1031 fl6->fl6_icmp_code = 0;
1032 fl6->flowi6_oif = oif;
1033 security_sk_classify_flow(sk, flowi6_to_flowi_common(fl6));
1034}
1035
1036int __init icmpv6_init(void)
1037{
1038 struct sock *sk;
1039 int err, i;
1040
1041 for_each_possible_cpu(i) {
1042 err = inet_ctl_sock_create(&sk, PF_INET6,
1043 SOCK_RAW, IPPROTO_ICMPV6, &init_net);
1044 if (err < 0) {
1045 pr_err("Failed to initialize the ICMP6 control socket (err %d)\n",
1046 err);
1047 return err;
1048 }
1049
1050 per_cpu(ipv6_icmp_sk, i) = sk;
1051
1052 /* Enough space for 2 64K ICMP packets, including
1053 * sk_buff struct overhead.
1054 */
1055 sk->sk_sndbuf = 2 * SKB_TRUESIZE(64 * 1024);
1056 }
1057
1058 err = -EAGAIN;
1059 if (inet6_add_protocol(&icmpv6_protocol, IPPROTO_ICMPV6) < 0)
1060 goto fail;
1061
1062 err = inet6_register_icmp_sender(icmp6_send);
1063 if (err)
1064 goto sender_reg_err;
1065 return 0;
1066
1067sender_reg_err:
1068 inet6_del_protocol(&icmpv6_protocol, IPPROTO_ICMPV6);
1069fail:
1070 pr_err("Failed to register ICMP6 protocol\n");
1071 return err;
1072}
1073
1074void icmpv6_cleanup(void)
1075{
1076 inet6_unregister_icmp_sender(icmp6_send);
1077 inet6_del_protocol(&icmpv6_protocol, IPPROTO_ICMPV6);
1078}
1079
1080
1081static const struct icmp6_err {
1082 int err;
1083 int fatal;
1084} tab_unreach[] = {
1085 { /* NOROUTE */
1086 .err = ENETUNREACH,
1087 .fatal = 0,
1088 },
1089 { /* ADM_PROHIBITED */
1090 .err = EACCES,
1091 .fatal = 1,
1092 },
1093 { /* Was NOT_NEIGHBOUR, now reserved */
1094 .err = EHOSTUNREACH,
1095 .fatal = 0,
1096 },
1097 { /* ADDR_UNREACH */
1098 .err = EHOSTUNREACH,
1099 .fatal = 0,
1100 },
1101 { /* PORT_UNREACH */
1102 .err = ECONNREFUSED,
1103 .fatal = 1,
1104 },
1105 { /* POLICY_FAIL */
1106 .err = EACCES,
1107 .fatal = 1,
1108 },
1109 { /* REJECT_ROUTE */
1110 .err = EACCES,
1111 .fatal = 1,
1112 },
1113};
1114
1115int icmpv6_err_convert(u8 type, u8 code, int *err)
1116{
1117 int fatal = 0;
1118
1119 *err = EPROTO;
1120
1121 switch (type) {
1122 case ICMPV6_DEST_UNREACH:
1123 fatal = 1;
1124 if (code < ARRAY_SIZE(tab_unreach)) {
1125 *err = tab_unreach[code].err;
1126 fatal = tab_unreach[code].fatal;
1127 }
1128 break;
1129
1130 case ICMPV6_PKT_TOOBIG:
1131 *err = EMSGSIZE;
1132 break;
1133
1134 case ICMPV6_PARAMPROB:
1135 *err = EPROTO;
1136 fatal = 1;
1137 break;
1138
1139 case ICMPV6_TIME_EXCEED:
1140 *err = EHOSTUNREACH;
1141 break;
1142 }
1143
1144 return fatal;
1145}
1146EXPORT_SYMBOL(icmpv6_err_convert);
1147
1148#ifdef CONFIG_SYSCTL
1149static struct ctl_table ipv6_icmp_table_template[] = {
1150 {
1151 .procname = "ratelimit",
1152 .data = &init_net.ipv6.sysctl.icmpv6_time,
1153 .maxlen = sizeof(int),
1154 .mode = 0644,
1155 .proc_handler = proc_dointvec_ms_jiffies,
1156 },
1157 {
1158 .procname = "echo_ignore_all",
1159 .data = &init_net.ipv6.sysctl.icmpv6_echo_ignore_all,
1160 .maxlen = sizeof(u8),
1161 .mode = 0644,
1162 .proc_handler = proc_dou8vec_minmax,
1163 },
1164 {
1165 .procname = "echo_ignore_multicast",
1166 .data = &init_net.ipv6.sysctl.icmpv6_echo_ignore_multicast,
1167 .maxlen = sizeof(u8),
1168 .mode = 0644,
1169 .proc_handler = proc_dou8vec_minmax,
1170 },
1171 {
1172 .procname = "echo_ignore_anycast",
1173 .data = &init_net.ipv6.sysctl.icmpv6_echo_ignore_anycast,
1174 .maxlen = sizeof(u8),
1175 .mode = 0644,
1176 .proc_handler = proc_dou8vec_minmax,
1177 },
1178 {
1179 .procname = "ratemask",
1180 .data = &init_net.ipv6.sysctl.icmpv6_ratemask_ptr,
1181 .maxlen = ICMPV6_MSG_MAX + 1,
1182 .mode = 0644,
1183 .proc_handler = proc_do_large_bitmap,
1184 },
1185 { },
1186};
1187
1188struct ctl_table * __net_init ipv6_icmp_sysctl_init(struct net *net)
1189{
1190 struct ctl_table *table;
1191
1192 table = kmemdup(ipv6_icmp_table_template,
1193 sizeof(ipv6_icmp_table_template),
1194 GFP_KERNEL);
1195
1196 if (table) {
1197 table[0].data = &net->ipv6.sysctl.icmpv6_time;
1198 table[1].data = &net->ipv6.sysctl.icmpv6_echo_ignore_all;
1199 table[2].data = &net->ipv6.sysctl.icmpv6_echo_ignore_multicast;
1200 table[3].data = &net->ipv6.sysctl.icmpv6_echo_ignore_anycast;
1201 table[4].data = &net->ipv6.sysctl.icmpv6_ratemask_ptr;
1202 }
1203 return table;
1204}
1205#endif