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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
72#include <asm/uaccess.h>
73
74/*
75 * The ICMP socket(s). This is the most convenient way to flow control
76 * our ICMP output as well as maintain a clean interface throughout
77 * all layers. All Socketless IP sends will soon be gone.
78 *
79 * On SMP we have one ICMP socket per-cpu.
80 */
81static inline struct sock *icmpv6_sk(struct net *net)
82{
83 return net->ipv6.icmp_sk[smp_processor_id()];
84}
85
86static void icmpv6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
87 u8 type, u8 code, int offset, __be32 info)
88{
89 /* icmpv6_notify checks 8 bytes can be pulled, icmp6hdr is 8 bytes */
90 struct icmp6hdr *icmp6 = (struct icmp6hdr *) (skb->data + offset);
91 struct net *net = dev_net(skb->dev);
92
93 if (type == ICMPV6_PKT_TOOBIG)
94 ip6_update_pmtu(skb, net, info, 0, 0);
95 else if (type == NDISC_REDIRECT)
96 ip6_redirect(skb, net, skb->dev->ifindex, 0);
97
98 if (!(type & ICMPV6_INFOMSG_MASK))
99 if (icmp6->icmp6_type == ICMPV6_ECHO_REQUEST)
100 ping_err(skb, offset, info);
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
111static __inline__ struct sock *icmpv6_xmit_lock(struct net *net)
112{
113 struct sock *sk;
114
115 local_bh_disable();
116
117 sk = icmpv6_sk(net);
118 if (unlikely(!spin_trylock(&sk->sk_lock.slock))) {
119 /* This can happen if the output path (f.e. SIT or
120 * ip6ip6 tunnel) signals dst_link_failure() for an
121 * outgoing ICMP6 packet.
122 */
123 local_bh_enable();
124 return NULL;
125 }
126 return sk;
127}
128
129static __inline__ void icmpv6_xmit_unlock(struct sock *sk)
130{
131 spin_unlock_bh(&sk->sk_lock.slock);
132}
133
134/*
135 * Figure out, may we reply to this packet with icmp error.
136 *
137 * We do not reply, if:
138 * - it was icmp error message.
139 * - it is truncated, so that it is known, that protocol is ICMPV6
140 * (i.e. in the middle of some exthdr)
141 *
142 * --ANK (980726)
143 */
144
145static bool is_ineligible(const struct sk_buff *skb)
146{
147 int ptr = (u8 *)(ipv6_hdr(skb) + 1) - skb->data;
148 int len = skb->len - ptr;
149 __u8 nexthdr = ipv6_hdr(skb)->nexthdr;
150 __be16 frag_off;
151
152 if (len < 0)
153 return true;
154
155 ptr = ipv6_skip_exthdr(skb, ptr, &nexthdr, &frag_off);
156 if (ptr < 0)
157 return false;
158 if (nexthdr == IPPROTO_ICMPV6) {
159 u8 _type, *tp;
160 tp = skb_header_pointer(skb,
161 ptr+offsetof(struct icmp6hdr, icmp6_type),
162 sizeof(_type), &_type);
163 if (tp == NULL ||
164 !(*tp & ICMPV6_INFOMSG_MASK))
165 return true;
166 }
167 return false;
168}
169
170/*
171 * Check the ICMP output rate limit
172 */
173static inline bool icmpv6_xrlim_allow(struct sock *sk, u8 type,
174 struct flowi6 *fl6)
175{
176 struct dst_entry *dst;
177 struct net *net = sock_net(sk);
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 struct inet_peer *peer;
203
204 /* Give more bandwidth to wider prefixes. */
205 if (rt->rt6i_dst.plen < 128)
206 tmo >>= ((128 - rt->rt6i_dst.plen)>>5);
207
208 peer = inet_getpeer_v6(net->ipv6.peers, &rt->rt6i_dst.addr, 1);
209 res = inet_peer_xrlim_allow(peer, tmo);
210 if (peer)
211 inet_putpeer(peer);
212 }
213 dst_release(dst);
214 return res;
215}
216
217/*
218 * an inline helper for the "simple" if statement below
219 * checks if parameter problem report is caused by an
220 * unrecognized IPv6 option that has the Option Type
221 * highest-order two bits set to 10
222 */
223
224static bool opt_unrec(struct sk_buff *skb, __u32 offset)
225{
226 u8 _optval, *op;
227
228 offset += skb_network_offset(skb);
229 op = skb_header_pointer(skb, offset, sizeof(_optval), &_optval);
230 if (op == NULL)
231 return true;
232 return (*op & 0xC0) == 0x80;
233}
234
235int icmpv6_push_pending_frames(struct sock *sk, struct flowi6 *fl6,
236 struct icmp6hdr *thdr, int len)
237{
238 struct sk_buff *skb;
239 struct icmp6hdr *icmp6h;
240 int err = 0;
241
242 if ((skb = skb_peek(&sk->sk_write_queue)) == NULL)
243 goto out;
244
245 icmp6h = icmp6_hdr(skb);
246 memcpy(icmp6h, thdr, sizeof(struct icmp6hdr));
247 icmp6h->icmp6_cksum = 0;
248
249 if (skb_queue_len(&sk->sk_write_queue) == 1) {
250 skb->csum = csum_partial(icmp6h,
251 sizeof(struct icmp6hdr), skb->csum);
252 icmp6h->icmp6_cksum = csum_ipv6_magic(&fl6->saddr,
253 &fl6->daddr,
254 len, fl6->flowi6_proto,
255 skb->csum);
256 } else {
257 __wsum tmp_csum = 0;
258
259 skb_queue_walk(&sk->sk_write_queue, skb) {
260 tmp_csum = csum_add(tmp_csum, skb->csum);
261 }
262
263 tmp_csum = csum_partial(icmp6h,
264 sizeof(struct icmp6hdr), tmp_csum);
265 icmp6h->icmp6_cksum = csum_ipv6_magic(&fl6->saddr,
266 &fl6->daddr,
267 len, fl6->flowi6_proto,
268 tmp_csum);
269 }
270 ip6_push_pending_frames(sk);
271out:
272 return err;
273}
274
275struct icmpv6_msg {
276 struct sk_buff *skb;
277 int offset;
278 uint8_t type;
279};
280
281static int icmpv6_getfrag(void *from, char *to, int offset, int len, int odd, struct sk_buff *skb)
282{
283 struct icmpv6_msg *msg = (struct icmpv6_msg *) from;
284 struct sk_buff *org_skb = msg->skb;
285 __wsum csum = 0;
286
287 csum = skb_copy_and_csum_bits(org_skb, msg->offset + offset,
288 to, len, csum);
289 skb->csum = csum_block_add(skb->csum, csum, odd);
290 if (!(msg->type & ICMPV6_INFOMSG_MASK))
291 nf_ct_attach(skb, org_skb);
292 return 0;
293}
294
295#if IS_ENABLED(CONFIG_IPV6_MIP6)
296static void mip6_addr_swap(struct sk_buff *skb)
297{
298 struct ipv6hdr *iph = ipv6_hdr(skb);
299 struct inet6_skb_parm *opt = IP6CB(skb);
300 struct ipv6_destopt_hao *hao;
301 struct in6_addr tmp;
302 int off;
303
304 if (opt->dsthao) {
305 off = ipv6_find_tlv(skb, opt->dsthao, IPV6_TLV_HAO);
306 if (likely(off >= 0)) {
307 hao = (struct ipv6_destopt_hao *)
308 (skb_network_header(skb) + off);
309 tmp = iph->saddr;
310 iph->saddr = hao->addr;
311 hao->addr = tmp;
312 }
313 }
314}
315#else
316static inline void mip6_addr_swap(struct sk_buff *skb) {}
317#endif
318
319static struct dst_entry *icmpv6_route_lookup(struct net *net,
320 struct sk_buff *skb,
321 struct sock *sk,
322 struct flowi6 *fl6)
323{
324 struct dst_entry *dst, *dst2;
325 struct flowi6 fl2;
326 int err;
327
328 err = ip6_dst_lookup(sk, &dst, fl6);
329 if (err)
330 return ERR_PTR(err);
331
332 /*
333 * We won't send icmp if the destination is known
334 * anycast.
335 */
336 if (((struct rt6_info *)dst)->rt6i_flags & RTF_ANYCAST) {
337 LIMIT_NETDEBUG(KERN_DEBUG "icmp6_send: acast source\n");
338 dst_release(dst);
339 return ERR_PTR(-EINVAL);
340 }
341
342 /* No need to clone since we're just using its address. */
343 dst2 = dst;
344
345 dst = xfrm_lookup(net, dst, flowi6_to_flowi(fl6), sk, 0);
346 if (!IS_ERR(dst)) {
347 if (dst != dst2)
348 return dst;
349 } else {
350 if (PTR_ERR(dst) == -EPERM)
351 dst = NULL;
352 else
353 return dst;
354 }
355
356 err = xfrm_decode_session_reverse(skb, flowi6_to_flowi(&fl2), AF_INET6);
357 if (err)
358 goto relookup_failed;
359
360 err = ip6_dst_lookup(sk, &dst2, &fl2);
361 if (err)
362 goto relookup_failed;
363
364 dst2 = xfrm_lookup(net, dst2, flowi6_to_flowi(&fl2), sk, XFRM_LOOKUP_ICMP);
365 if (!IS_ERR(dst2)) {
366 dst_release(dst);
367 dst = dst2;
368 } else {
369 err = PTR_ERR(dst2);
370 if (err == -EPERM) {
371 dst_release(dst);
372 return dst2;
373 } else
374 goto relookup_failed;
375 }
376
377relookup_failed:
378 if (dst)
379 return dst;
380 return ERR_PTR(err);
381}
382
383/*
384 * Send an ICMP message in response to a packet in error
385 */
386static void icmp6_send(struct sk_buff *skb, u8 type, u8 code, __u32 info)
387{
388 struct net *net = dev_net(skb->dev);
389 struct inet6_dev *idev = NULL;
390 struct ipv6hdr *hdr = ipv6_hdr(skb);
391 struct sock *sk;
392 struct ipv6_pinfo *np;
393 const struct in6_addr *saddr = NULL;
394 struct dst_entry *dst;
395 struct icmp6hdr tmp_hdr;
396 struct flowi6 fl6;
397 struct icmpv6_msg msg;
398 int iif = 0;
399 int addr_type = 0;
400 int len;
401 int hlimit;
402 int err = 0;
403
404 if ((u8 *)hdr < skb->head ||
405 (skb_network_header(skb) + sizeof(*hdr)) > skb_tail_pointer(skb))
406 return;
407
408 /*
409 * Make sure we respect the rules
410 * i.e. RFC 1885 2.4(e)
411 * Rule (e.1) is enforced by not using icmp6_send
412 * in any code that processes icmp errors.
413 */
414 addr_type = ipv6_addr_type(&hdr->daddr);
415
416 if (ipv6_chk_addr(net, &hdr->daddr, skb->dev, 0) ||
417 ipv6_chk_acast_addr_src(net, skb->dev, &hdr->daddr))
418 saddr = &hdr->daddr;
419
420 /*
421 * Dest addr check
422 */
423
424 if ((addr_type & IPV6_ADDR_MULTICAST || skb->pkt_type != PACKET_HOST)) {
425 if (type != ICMPV6_PKT_TOOBIG &&
426 !(type == ICMPV6_PARAMPROB &&
427 code == ICMPV6_UNK_OPTION &&
428 (opt_unrec(skb, info))))
429 return;
430
431 saddr = NULL;
432 }
433
434 addr_type = ipv6_addr_type(&hdr->saddr);
435
436 /*
437 * Source addr check
438 */
439
440 if (__ipv6_addr_needs_scope_id(addr_type))
441 iif = skb->dev->ifindex;
442
443 /*
444 * Must not send error if the source does not uniquely
445 * identify a single node (RFC2463 Section 2.4).
446 * We check unspecified / multicast addresses here,
447 * and anycast addresses will be checked later.
448 */
449 if ((addr_type == IPV6_ADDR_ANY) || (addr_type & IPV6_ADDR_MULTICAST)) {
450 LIMIT_NETDEBUG(KERN_DEBUG "icmp6_send: addr_any/mcast source\n");
451 return;
452 }
453
454 /*
455 * Never answer to a ICMP packet.
456 */
457 if (is_ineligible(skb)) {
458 LIMIT_NETDEBUG(KERN_DEBUG "icmp6_send: no reply to icmp error\n");
459 return;
460 }
461
462 mip6_addr_swap(skb);
463
464 memset(&fl6, 0, sizeof(fl6));
465 fl6.flowi6_proto = IPPROTO_ICMPV6;
466 fl6.daddr = hdr->saddr;
467 if (saddr)
468 fl6.saddr = *saddr;
469 fl6.flowi6_oif = iif;
470 fl6.fl6_icmp_type = type;
471 fl6.fl6_icmp_code = code;
472 security_skb_classify_flow(skb, flowi6_to_flowi(&fl6));
473
474 sk = icmpv6_xmit_lock(net);
475 if (sk == NULL)
476 return;
477 np = inet6_sk(sk);
478
479 if (!icmpv6_xrlim_allow(sk, type, &fl6))
480 goto out;
481
482 tmp_hdr.icmp6_type = type;
483 tmp_hdr.icmp6_code = code;
484 tmp_hdr.icmp6_cksum = 0;
485 tmp_hdr.icmp6_pointer = htonl(info);
486
487 if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr))
488 fl6.flowi6_oif = np->mcast_oif;
489 else if (!fl6.flowi6_oif)
490 fl6.flowi6_oif = np->ucast_oif;
491
492 dst = icmpv6_route_lookup(net, skb, sk, &fl6);
493 if (IS_ERR(dst))
494 goto out;
495
496 if (ipv6_addr_is_multicast(&fl6.daddr))
497 hlimit = np->mcast_hops;
498 else
499 hlimit = np->hop_limit;
500 if (hlimit < 0)
501 hlimit = ip6_dst_hoplimit(dst);
502
503 msg.skb = skb;
504 msg.offset = skb_network_offset(skb);
505 msg.type = type;
506
507 len = skb->len - msg.offset;
508 len = min_t(unsigned int, len, IPV6_MIN_MTU - sizeof(struct ipv6hdr) -sizeof(struct icmp6hdr));
509 if (len < 0) {
510 LIMIT_NETDEBUG(KERN_DEBUG "icmp: len problem\n");
511 goto out_dst_release;
512 }
513
514 rcu_read_lock();
515 idev = __in6_dev_get(skb->dev);
516
517 err = ip6_append_data(sk, icmpv6_getfrag, &msg,
518 len + sizeof(struct icmp6hdr),
519 sizeof(struct icmp6hdr), hlimit,
520 np->tclass, NULL, &fl6, (struct rt6_info *)dst,
521 MSG_DONTWAIT, np->dontfrag);
522 if (err) {
523 ICMP6_INC_STATS(net, idev, ICMP6_MIB_OUTERRORS);
524 ip6_flush_pending_frames(sk);
525 } else {
526 err = icmpv6_push_pending_frames(sk, &fl6, &tmp_hdr,
527 len + sizeof(struct icmp6hdr));
528 }
529 rcu_read_unlock();
530out_dst_release:
531 dst_release(dst);
532out:
533 icmpv6_xmit_unlock(sk);
534}
535
536/* Slightly more convenient version of icmp6_send.
537 */
538void icmpv6_param_prob(struct sk_buff *skb, u8 code, int pos)
539{
540 icmp6_send(skb, ICMPV6_PARAMPROB, code, pos);
541 kfree_skb(skb);
542}
543
544static void icmpv6_echo_reply(struct sk_buff *skb)
545{
546 struct net *net = dev_net(skb->dev);
547 struct sock *sk;
548 struct inet6_dev *idev;
549 struct ipv6_pinfo *np;
550 const struct in6_addr *saddr = NULL;
551 struct icmp6hdr *icmph = icmp6_hdr(skb);
552 struct icmp6hdr tmp_hdr;
553 struct flowi6 fl6;
554 struct icmpv6_msg msg;
555 struct dst_entry *dst;
556 int err = 0;
557 int hlimit;
558 u8 tclass;
559
560 saddr = &ipv6_hdr(skb)->daddr;
561
562 if (!ipv6_unicast_destination(skb) &&
563 !(net->ipv6.sysctl.anycast_src_echo_reply &&
564 ipv6_anycast_destination(skb)))
565 saddr = NULL;
566
567 memcpy(&tmp_hdr, icmph, sizeof(tmp_hdr));
568 tmp_hdr.icmp6_type = ICMPV6_ECHO_REPLY;
569
570 memset(&fl6, 0, sizeof(fl6));
571 fl6.flowi6_proto = IPPROTO_ICMPV6;
572 fl6.daddr = ipv6_hdr(skb)->saddr;
573 if (saddr)
574 fl6.saddr = *saddr;
575 fl6.flowi6_oif = skb->dev->ifindex;
576 fl6.fl6_icmp_type = ICMPV6_ECHO_REPLY;
577 security_skb_classify_flow(skb, flowi6_to_flowi(&fl6));
578
579 sk = icmpv6_xmit_lock(net);
580 if (sk == NULL)
581 return;
582 np = inet6_sk(sk);
583
584 if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr))
585 fl6.flowi6_oif = np->mcast_oif;
586 else if (!fl6.flowi6_oif)
587 fl6.flowi6_oif = np->ucast_oif;
588
589 err = ip6_dst_lookup(sk, &dst, &fl6);
590 if (err)
591 goto out;
592 dst = xfrm_lookup(net, dst, flowi6_to_flowi(&fl6), sk, 0);
593 if (IS_ERR(dst))
594 goto out;
595
596 if (ipv6_addr_is_multicast(&fl6.daddr))
597 hlimit = np->mcast_hops;
598 else
599 hlimit = np->hop_limit;
600 if (hlimit < 0)
601 hlimit = ip6_dst_hoplimit(dst);
602
603 idev = __in6_dev_get(skb->dev);
604
605 msg.skb = skb;
606 msg.offset = 0;
607 msg.type = ICMPV6_ECHO_REPLY;
608
609 tclass = ipv6_get_dsfield(ipv6_hdr(skb));
610 err = ip6_append_data(sk, icmpv6_getfrag, &msg, skb->len + sizeof(struct icmp6hdr),
611 sizeof(struct icmp6hdr), hlimit, tclass, NULL, &fl6,
612 (struct rt6_info *)dst, MSG_DONTWAIT,
613 np->dontfrag);
614
615 if (err) {
616 ICMP6_INC_STATS_BH(net, idev, ICMP6_MIB_OUTERRORS);
617 ip6_flush_pending_frames(sk);
618 } else {
619 err = icmpv6_push_pending_frames(sk, &fl6, &tmp_hdr,
620 skb->len + sizeof(struct icmp6hdr));
621 }
622 dst_release(dst);
623out:
624 icmpv6_xmit_unlock(sk);
625}
626
627void icmpv6_notify(struct sk_buff *skb, u8 type, u8 code, __be32 info)
628{
629 const struct inet6_protocol *ipprot;
630 int inner_offset;
631 __be16 frag_off;
632 u8 nexthdr;
633
634 if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
635 return;
636
637 nexthdr = ((struct ipv6hdr *)skb->data)->nexthdr;
638 if (ipv6_ext_hdr(nexthdr)) {
639 /* now skip over extension headers */
640 inner_offset = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr),
641 &nexthdr, &frag_off);
642 if (inner_offset<0)
643 return;
644 } else {
645 inner_offset = sizeof(struct ipv6hdr);
646 }
647
648 /* Checkin header including 8 bytes of inner protocol header. */
649 if (!pskb_may_pull(skb, inner_offset+8))
650 return;
651
652 /* BUGGG_FUTURE: we should try to parse exthdrs in this packet.
653 Without this we will not able f.e. to make source routed
654 pmtu discovery.
655 Corresponding argument (opt) to notifiers is already added.
656 --ANK (980726)
657 */
658
659 rcu_read_lock();
660 ipprot = rcu_dereference(inet6_protos[nexthdr]);
661 if (ipprot && ipprot->err_handler)
662 ipprot->err_handler(skb, NULL, type, code, inner_offset, info);
663 rcu_read_unlock();
664
665 raw6_icmp_error(skb, nexthdr, type, code, inner_offset, info);
666}
667
668/*
669 * Handle icmp messages
670 */
671
672static int icmpv6_rcv(struct sk_buff *skb)
673{
674 struct net_device *dev = skb->dev;
675 struct inet6_dev *idev = __in6_dev_get(dev);
676 const struct in6_addr *saddr, *daddr;
677 struct icmp6hdr *hdr;
678 u8 type;
679
680 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) {
681 struct sec_path *sp = skb_sec_path(skb);
682 int nh;
683
684 if (!(sp && sp->xvec[sp->len - 1]->props.flags &
685 XFRM_STATE_ICMP))
686 goto drop_no_count;
687
688 if (!pskb_may_pull(skb, sizeof(*hdr) + sizeof(struct ipv6hdr)))
689 goto drop_no_count;
690
691 nh = skb_network_offset(skb);
692 skb_set_network_header(skb, sizeof(*hdr));
693
694 if (!xfrm6_policy_check_reverse(NULL, XFRM_POLICY_IN, skb))
695 goto drop_no_count;
696
697 skb_set_network_header(skb, nh);
698 }
699
700 ICMP6_INC_STATS_BH(dev_net(dev), idev, ICMP6_MIB_INMSGS);
701
702 saddr = &ipv6_hdr(skb)->saddr;
703 daddr = &ipv6_hdr(skb)->daddr;
704
705 /* Perform checksum. */
706 switch (skb->ip_summed) {
707 case CHECKSUM_COMPLETE:
708 if (!csum_ipv6_magic(saddr, daddr, skb->len, IPPROTO_ICMPV6,
709 skb->csum))
710 break;
711 /* fall through */
712 case CHECKSUM_NONE:
713 skb->csum = ~csum_unfold(csum_ipv6_magic(saddr, daddr, skb->len,
714 IPPROTO_ICMPV6, 0));
715 if (__skb_checksum_complete(skb)) {
716 LIMIT_NETDEBUG(KERN_DEBUG
717 "ICMPv6 checksum failed [%pI6c > %pI6c]\n",
718 saddr, daddr);
719 goto csum_error;
720 }
721 }
722
723 if (!pskb_pull(skb, sizeof(*hdr)))
724 goto discard_it;
725
726 hdr = icmp6_hdr(skb);
727
728 type = hdr->icmp6_type;
729
730 ICMP6MSGIN_INC_STATS_BH(dev_net(dev), idev, type);
731
732 switch (type) {
733 case ICMPV6_ECHO_REQUEST:
734 icmpv6_echo_reply(skb);
735 break;
736
737 case ICMPV6_ECHO_REPLY:
738 ping_rcv(skb);
739 break;
740
741 case ICMPV6_PKT_TOOBIG:
742 /* BUGGG_FUTURE: if packet contains rthdr, we cannot update
743 standard destination cache. Seems, only "advanced"
744 destination cache will allow to solve this problem
745 --ANK (980726)
746 */
747 if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
748 goto discard_it;
749 hdr = icmp6_hdr(skb);
750
751 /*
752 * Drop through to notify
753 */
754
755 case ICMPV6_DEST_UNREACH:
756 case ICMPV6_TIME_EXCEED:
757 case ICMPV6_PARAMPROB:
758 icmpv6_notify(skb, type, hdr->icmp6_code, hdr->icmp6_mtu);
759 break;
760
761 case NDISC_ROUTER_SOLICITATION:
762 case NDISC_ROUTER_ADVERTISEMENT:
763 case NDISC_NEIGHBOUR_SOLICITATION:
764 case NDISC_NEIGHBOUR_ADVERTISEMENT:
765 case NDISC_REDIRECT:
766 ndisc_rcv(skb);
767 break;
768
769 case ICMPV6_MGM_QUERY:
770 igmp6_event_query(skb);
771 break;
772
773 case ICMPV6_MGM_REPORT:
774 igmp6_event_report(skb);
775 break;
776
777 case ICMPV6_MGM_REDUCTION:
778 case ICMPV6_NI_QUERY:
779 case ICMPV6_NI_REPLY:
780 case ICMPV6_MLD2_REPORT:
781 case ICMPV6_DHAAD_REQUEST:
782 case ICMPV6_DHAAD_REPLY:
783 case ICMPV6_MOBILE_PREFIX_SOL:
784 case ICMPV6_MOBILE_PREFIX_ADV:
785 break;
786
787 default:
788 LIMIT_NETDEBUG(KERN_DEBUG "icmpv6: msg of unknown type\n");
789
790 /* informational */
791 if (type & ICMPV6_INFOMSG_MASK)
792 break;
793
794 /*
795 * error of unknown type.
796 * must pass to upper level
797 */
798
799 icmpv6_notify(skb, type, hdr->icmp6_code, hdr->icmp6_mtu);
800 }
801
802 kfree_skb(skb);
803 return 0;
804
805csum_error:
806 ICMP6_INC_STATS_BH(dev_net(dev), idev, ICMP6_MIB_CSUMERRORS);
807discard_it:
808 ICMP6_INC_STATS_BH(dev_net(dev), idev, ICMP6_MIB_INERRORS);
809drop_no_count:
810 kfree_skb(skb);
811 return 0;
812}
813
814void icmpv6_flow_init(struct sock *sk, struct flowi6 *fl6,
815 u8 type,
816 const struct in6_addr *saddr,
817 const struct in6_addr *daddr,
818 int oif)
819{
820 memset(fl6, 0, sizeof(*fl6));
821 fl6->saddr = *saddr;
822 fl6->daddr = *daddr;
823 fl6->flowi6_proto = IPPROTO_ICMPV6;
824 fl6->fl6_icmp_type = type;
825 fl6->fl6_icmp_code = 0;
826 fl6->flowi6_oif = oif;
827 security_sk_classify_flow(sk, flowi6_to_flowi(fl6));
828}
829
830/*
831 * Special lock-class for __icmpv6_sk:
832 */
833static struct lock_class_key icmpv6_socket_sk_dst_lock_key;
834
835static int __net_init icmpv6_sk_init(struct net *net)
836{
837 struct sock *sk;
838 int err, i, j;
839
840 net->ipv6.icmp_sk =
841 kzalloc(nr_cpu_ids * sizeof(struct sock *), GFP_KERNEL);
842 if (net->ipv6.icmp_sk == NULL)
843 return -ENOMEM;
844
845 for_each_possible_cpu(i) {
846 err = inet_ctl_sock_create(&sk, PF_INET6,
847 SOCK_RAW, IPPROTO_ICMPV6, net);
848 if (err < 0) {
849 pr_err("Failed to initialize the ICMP6 control socket (err %d)\n",
850 err);
851 goto fail;
852 }
853
854 net->ipv6.icmp_sk[i] = sk;
855
856 /*
857 * Split off their lock-class, because sk->sk_dst_lock
858 * gets used from softirqs, which is safe for
859 * __icmpv6_sk (because those never get directly used
860 * via userspace syscalls), but unsafe for normal sockets.
861 */
862 lockdep_set_class(&sk->sk_dst_lock,
863 &icmpv6_socket_sk_dst_lock_key);
864
865 /* Enough space for 2 64K ICMP packets, including
866 * sk_buff struct overhead.
867 */
868 sk->sk_sndbuf = 2 * SKB_TRUESIZE(64 * 1024);
869 }
870 return 0;
871
872 fail:
873 for (j = 0; j < i; j++)
874 inet_ctl_sock_destroy(net->ipv6.icmp_sk[j]);
875 kfree(net->ipv6.icmp_sk);
876 return err;
877}
878
879static void __net_exit icmpv6_sk_exit(struct net *net)
880{
881 int i;
882
883 for_each_possible_cpu(i) {
884 inet_ctl_sock_destroy(net->ipv6.icmp_sk[i]);
885 }
886 kfree(net->ipv6.icmp_sk);
887}
888
889static struct pernet_operations icmpv6_sk_ops = {
890 .init = icmpv6_sk_init,
891 .exit = icmpv6_sk_exit,
892};
893
894int __init icmpv6_init(void)
895{
896 int err;
897
898 err = register_pernet_subsys(&icmpv6_sk_ops);
899 if (err < 0)
900 return err;
901
902 err = -EAGAIN;
903 if (inet6_add_protocol(&icmpv6_protocol, IPPROTO_ICMPV6) < 0)
904 goto fail;
905
906 err = inet6_register_icmp_sender(icmp6_send);
907 if (err)
908 goto sender_reg_err;
909 return 0;
910
911sender_reg_err:
912 inet6_del_protocol(&icmpv6_protocol, IPPROTO_ICMPV6);
913fail:
914 pr_err("Failed to register ICMP6 protocol\n");
915 unregister_pernet_subsys(&icmpv6_sk_ops);
916 return err;
917}
918
919void icmpv6_cleanup(void)
920{
921 inet6_unregister_icmp_sender(icmp6_send);
922 unregister_pernet_subsys(&icmpv6_sk_ops);
923 inet6_del_protocol(&icmpv6_protocol, IPPROTO_ICMPV6);
924}
925
926
927static const struct icmp6_err {
928 int err;
929 int fatal;
930} tab_unreach[] = {
931 { /* NOROUTE */
932 .err = ENETUNREACH,
933 .fatal = 0,
934 },
935 { /* ADM_PROHIBITED */
936 .err = EACCES,
937 .fatal = 1,
938 },
939 { /* Was NOT_NEIGHBOUR, now reserved */
940 .err = EHOSTUNREACH,
941 .fatal = 0,
942 },
943 { /* ADDR_UNREACH */
944 .err = EHOSTUNREACH,
945 .fatal = 0,
946 },
947 { /* PORT_UNREACH */
948 .err = ECONNREFUSED,
949 .fatal = 1,
950 },
951 { /* POLICY_FAIL */
952 .err = EACCES,
953 .fatal = 1,
954 },
955 { /* REJECT_ROUTE */
956 .err = EACCES,
957 .fatal = 1,
958 },
959};
960
961int icmpv6_err_convert(u8 type, u8 code, int *err)
962{
963 int fatal = 0;
964
965 *err = EPROTO;
966
967 switch (type) {
968 case ICMPV6_DEST_UNREACH:
969 fatal = 1;
970 if (code < ARRAY_SIZE(tab_unreach)) {
971 *err = tab_unreach[code].err;
972 fatal = tab_unreach[code].fatal;
973 }
974 break;
975
976 case ICMPV6_PKT_TOOBIG:
977 *err = EMSGSIZE;
978 break;
979
980 case ICMPV6_PARAMPROB:
981 *err = EPROTO;
982 fatal = 1;
983 break;
984
985 case ICMPV6_TIME_EXCEED:
986 *err = EHOSTUNREACH;
987 break;
988 }
989
990 return fatal;
991}
992EXPORT_SYMBOL(icmpv6_err_convert);
993
994#ifdef CONFIG_SYSCTL
995static struct ctl_table ipv6_icmp_table_template[] = {
996 {
997 .procname = "ratelimit",
998 .data = &init_net.ipv6.sysctl.icmpv6_time,
999 .maxlen = sizeof(int),
1000 .mode = 0644,
1001 .proc_handler = proc_dointvec_ms_jiffies,
1002 },
1003 { },
1004};
1005
1006struct ctl_table * __net_init ipv6_icmp_sysctl_init(struct net *net)
1007{
1008 struct ctl_table *table;
1009
1010 table = kmemdup(ipv6_icmp_table_template,
1011 sizeof(ipv6_icmp_table_template),
1012 GFP_KERNEL);
1013
1014 if (table)
1015 table[0].data = &net->ipv6.sysctl.icmpv6_time;
1016
1017 return table;
1018}
1019#endif
1020
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