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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Internet Control Message Protocol (ICMPv6)
4 * Linux INET6 implementation
5 *
6 * Authors:
7 * Pedro Roque <[email protected]>
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_rcu(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 bool *apply_ratelimit)
180{
181 if (icmpv6_mask_allow(net, type))
182 return true;
183
184 if (icmp_global_allow(net)) {
185 *apply_ratelimit = true;
186 return true;
187 }
188 __ICMP_INC_STATS(net, ICMP_MIB_RATELIMITGLOBAL);
189 return false;
190}
191
192/*
193 * Check the ICMP output rate limit
194 */
195static bool icmpv6_xrlim_allow(struct sock *sk, u8 type,
196 struct flowi6 *fl6, bool apply_ratelimit)
197{
198 struct net *net = sock_net(sk);
199 struct net_device *dev;
200 struct dst_entry *dst;
201 bool res = false;
202
203 if (!apply_ratelimit)
204 return true;
205
206 /*
207 * Look up the output route.
208 * XXX: perhaps the expire for routing entries cloned by
209 * this lookup should be more aggressive (not longer than timeout).
210 */
211 dst = ip6_route_output(net, sk, fl6);
212 rcu_read_lock();
213 dev = dst_dev_rcu(dst);
214 if (dst->error) {
215 IP6_INC_STATS(net, ip6_dst_idev(dst),
216 IPSTATS_MIB_OUTNOROUTES);
217 } else if (dev && (dev->flags & IFF_LOOPBACK)) {
218 res = true;
219 } else {
220 int tmo = READ_ONCE(net->ipv6.sysctl.icmpv6_time);
221 struct inet_peer *peer;
222
223 if (!tmo) {
224 res = true;
225 } else {
226 peer = inet_getpeer_v6(net->ipv6.peers, &fl6->daddr);
227 res = inet_peer_xrlim_allow(peer, tmo);
228 }
229 }
230 rcu_read_unlock();
231 if (!res)
232 __ICMP6_INC_STATS(net, NULL, ICMP6_MIB_RATELIMITHOST);
233 else
234 icmp_global_consume(net);
235 dst_release(dst);
236 return res;
237}
238
239static bool icmpv6_rt_has_prefsrc(struct sock *sk, u8 type,
240 struct flowi6 *fl6)
241{
242 struct net *net = sock_net(sk);
243 struct dst_entry *dst;
244 bool res = false;
245
246 dst = ip6_route_output(net, sk, fl6);
247 if (!dst->error) {
248 struct rt6_info *rt = dst_rt6_info(dst);
249 struct in6_addr prefsrc;
250
251 rt6_get_prefsrc(rt, &prefsrc);
252 res = !ipv6_addr_any(&prefsrc);
253 }
254 dst_release(dst);
255 return res;
256}
257
258/*
259 * an inline helper for the "simple" if statement below
260 * checks if parameter problem report is caused by an
261 * unrecognized IPv6 option that has the Option Type
262 * highest-order two bits set to 10
263 */
264
265static bool opt_unrec(struct sk_buff *skb, __u32 offset)
266{
267 u8 _optval, *op;
268
269 offset += skb_network_offset(skb);
270 op = skb_header_pointer(skb, offset, sizeof(_optval), &_optval);
271 if (!op)
272 return true;
273 return (*op & 0xC0) == 0x80;
274}
275
276void icmpv6_push_pending_frames(struct sock *sk, struct flowi6 *fl6,
277 struct icmp6hdr *thdr, int len)
278{
279 struct sk_buff *skb;
280 struct icmp6hdr *icmp6h;
281
282 skb = skb_peek(&sk->sk_write_queue);
283 if (!skb)
284 return;
285
286 icmp6h = icmp6_hdr(skb);
287 memcpy(icmp6h, thdr, sizeof(struct icmp6hdr));
288 icmp6h->icmp6_cksum = 0;
289
290 if (skb_queue_len(&sk->sk_write_queue) == 1) {
291 skb->csum = csum_partial(icmp6h,
292 sizeof(struct icmp6hdr), skb->csum);
293 icmp6h->icmp6_cksum = csum_ipv6_magic(&fl6->saddr,
294 &fl6->daddr,
295 len, fl6->flowi6_proto,
296 skb->csum);
297 } else {
298 __wsum tmp_csum = 0;
299
300 skb_queue_walk(&sk->sk_write_queue, skb) {
301 tmp_csum = csum_add(tmp_csum, skb->csum);
302 }
303
304 tmp_csum = csum_partial(icmp6h,
305 sizeof(struct icmp6hdr), tmp_csum);
306 icmp6h->icmp6_cksum = csum_ipv6_magic(&fl6->saddr,
307 &fl6->daddr,
308 len, fl6->flowi6_proto,
309 tmp_csum);
310 }
311 ip6_push_pending_frames(sk);
312}
313
314struct icmpv6_msg {
315 struct sk_buff *skb;
316 int offset;
317 uint8_t type;
318};
319
320static int icmpv6_getfrag(void *from, char *to, int offset, int len, int odd, struct sk_buff *skb)
321{
322 struct icmpv6_msg *msg = (struct icmpv6_msg *) from;
323 struct sk_buff *org_skb = msg->skb;
324 __wsum csum;
325
326 csum = skb_copy_and_csum_bits(org_skb, msg->offset + offset,
327 to, len);
328 skb->csum = csum_block_add(skb->csum, csum, odd);
329 if (!(msg->type & ICMPV6_INFOMSG_MASK))
330 nf_ct_attach(skb, org_skb);
331 return 0;
332}
333
334#if IS_ENABLED(CONFIG_IPV6_MIP6)
335static void mip6_addr_swap(struct sk_buff *skb, const struct inet6_skb_parm *opt)
336{
337 struct ipv6hdr *iph = ipv6_hdr(skb);
338 struct ipv6_destopt_hao *hao;
339 int off;
340
341 if (opt->dsthao) {
342 off = ipv6_find_tlv(skb, opt->dsthao, IPV6_TLV_HAO);
343 if (likely(off >= 0)) {
344 hao = (struct ipv6_destopt_hao *)
345 (skb_network_header(skb) + off);
346 swap(iph->saddr, hao->addr);
347 }
348 }
349}
350#else
351static inline void mip6_addr_swap(struct sk_buff *skb, const struct inet6_skb_parm *opt) {}
352#endif
353
354static struct dst_entry *icmpv6_route_lookup(struct net *net,
355 struct sk_buff *skb,
356 struct sock *sk,
357 struct flowi6 *fl6)
358{
359 struct dst_entry *dst, *dst2;
360 struct flowi6 fl2;
361 int err;
362
363 err = ip6_dst_lookup(net, sk, &dst, fl6);
364 if (err)
365 return ERR_PTR(err);
366
367 /*
368 * We won't send icmp if the destination is known
369 * anycast unless we need to treat anycast as unicast.
370 */
371 if (!READ_ONCE(net->ipv6.sysctl.icmpv6_error_anycast_as_unicast) &&
372 ipv6_anycast_destination(dst, &fl6->daddr)) {
373 net_dbg_ratelimited("icmp6_send: acast source\n");
374 dst_release(dst);
375 return ERR_PTR(-EINVAL);
376 }
377
378 /* No need to clone since we're just using its address. */
379 dst2 = dst;
380
381 dst = xfrm_lookup(net, dst, flowi6_to_flowi(fl6), sk, 0);
382 if (!IS_ERR(dst)) {
383 if (dst != dst2)
384 return dst;
385 } else {
386 if (PTR_ERR(dst) == -EPERM)
387 dst = NULL;
388 else
389 return dst;
390 }
391
392 err = xfrm_decode_session_reverse(net, skb, flowi6_to_flowi(&fl2), AF_INET6);
393 if (err)
394 goto relookup_failed;
395
396 err = ip6_dst_lookup(net, sk, &dst2, &fl2);
397 if (err)
398 goto relookup_failed;
399
400 dst2 = xfrm_lookup(net, dst2, flowi6_to_flowi(&fl2), sk, XFRM_LOOKUP_ICMP);
401 if (!IS_ERR(dst2)) {
402 dst_release(dst);
403 dst = dst2;
404 } else {
405 err = PTR_ERR(dst2);
406 if (err == -EPERM) {
407 dst_release(dst);
408 return dst2;
409 } else
410 goto relookup_failed;
411 }
412
413relookup_failed:
414 if (dst)
415 return dst;
416 return ERR_PTR(err);
417}
418
419static struct net_device *icmp6_dev(const struct sk_buff *skb)
420{
421 struct net_device *dev = skb->dev;
422
423 /* for local traffic to local address, skb dev is the loopback
424 * device. Check if there is a dst attached to the skb and if so
425 * get the real device index. Same is needed for replies to a link
426 * local address on a device enslaved to an L3 master device
427 */
428 if (unlikely(dev->ifindex == LOOPBACK_IFINDEX || netif_is_l3_master(skb->dev))) {
429 const struct rt6_info *rt6 = skb_rt6_info(skb);
430
431 /* The destination could be an external IP in Ext Hdr (SRv6, RPL, etc.),
432 * and ip6_null_entry could be set to skb if no route is found.
433 */
434 if (rt6 && rt6->rt6i_idev)
435 dev = rt6->rt6i_idev->dev;
436 }
437
438 return dev;
439}
440
441static int icmp6_iif(const struct sk_buff *skb)
442{
443 return icmp6_dev(skb)->ifindex;
444}
445
446struct icmp6_ext_iio_addr6_subobj {
447 __be16 afi;
448 __be16 reserved;
449 struct in6_addr addr6;
450};
451
452static unsigned int icmp6_ext_iio_len(void)
453{
454 return sizeof(struct icmp_extobj_hdr) +
455 /* ifIndex */
456 sizeof(__be32) +
457 /* Interface Address Sub-Object */
458 sizeof(struct icmp6_ext_iio_addr6_subobj) +
459 /* Interface Name Sub-Object. Length must be a multiple of 4
460 * bytes.
461 */
462 ALIGN(sizeof(struct icmp_ext_iio_name_subobj), 4) +
463 /* MTU */
464 sizeof(__be32);
465}
466
467static unsigned int icmp6_ext_max_len(u8 ext_objs)
468{
469 unsigned int ext_max_len;
470
471 ext_max_len = sizeof(struct icmp_ext_hdr);
472
473 if (ext_objs & BIT(ICMP_ERR_EXT_IIO_IIF))
474 ext_max_len += icmp6_ext_iio_len();
475
476 return ext_max_len;
477}
478
479static struct in6_addr *icmp6_ext_iio_addr6_find(const struct net_device *dev)
480{
481 struct inet6_dev *in6_dev;
482 struct inet6_ifaddr *ifa;
483
484 in6_dev = __in6_dev_get(dev);
485 if (!in6_dev)
486 return NULL;
487
488 /* It is unclear from RFC 5837 which IP address should be chosen, but
489 * it makes sense to choose a global unicast address.
490 */
491 list_for_each_entry_rcu(ifa, &in6_dev->addr_list, if_list) {
492 if (ifa->flags & (IFA_F_TENTATIVE | IFA_F_DADFAILED))
493 continue;
494 if (ipv6_addr_type(&ifa->addr) != IPV6_ADDR_UNICAST ||
495 ipv6_addr_src_scope(&ifa->addr) != IPV6_ADDR_SCOPE_GLOBAL)
496 continue;
497 return &ifa->addr;
498 }
499
500 return NULL;
501}
502
503static void icmp6_ext_iio_iif_append(struct net *net, struct sk_buff *skb,
504 int iif)
505{
506 struct icmp_ext_iio_name_subobj *name_subobj;
507 struct icmp_extobj_hdr *objh;
508 struct net_device *dev;
509 struct in6_addr *addr6;
510 __be32 data;
511
512 if (!iif)
513 return;
514
515 /* Add the fields in the order specified by RFC 5837. */
516 objh = skb_put(skb, sizeof(*objh));
517 objh->class_num = ICMP_EXT_OBJ_CLASS_IIO;
518 objh->class_type = ICMP_EXT_CTYPE_IIO_ROLE(ICMP_EXT_CTYPE_IIO_ROLE_IIF);
519
520 data = htonl(iif);
521 skb_put_data(skb, &data, sizeof(__be32));
522 objh->class_type |= ICMP_EXT_CTYPE_IIO_IFINDEX;
523
524 rcu_read_lock();
525
526 dev = dev_get_by_index_rcu(net, iif);
527 if (!dev)
528 goto out;
529
530 addr6 = icmp6_ext_iio_addr6_find(dev);
531 if (addr6) {
532 struct icmp6_ext_iio_addr6_subobj *addr6_subobj;
533
534 addr6_subobj = skb_put_zero(skb, sizeof(*addr6_subobj));
535 addr6_subobj->afi = htons(ICMP_AFI_IP6);
536 addr6_subobj->addr6 = *addr6;
537 objh->class_type |= ICMP_EXT_CTYPE_IIO_IPADDR;
538 }
539
540 name_subobj = skb_put_zero(skb, ALIGN(sizeof(*name_subobj), 4));
541 name_subobj->len = ALIGN(sizeof(*name_subobj), 4);
542 netdev_copy_name(dev, name_subobj->name);
543 objh->class_type |= ICMP_EXT_CTYPE_IIO_NAME;
544
545 data = htonl(READ_ONCE(dev->mtu));
546 skb_put_data(skb, &data, sizeof(__be32));
547 objh->class_type |= ICMP_EXT_CTYPE_IIO_MTU;
548
549out:
550 rcu_read_unlock();
551 objh->length = htons(skb_tail_pointer(skb) - (unsigned char *)objh);
552}
553
554static void icmp6_ext_objs_append(struct net *net, struct sk_buff *skb,
555 u8 ext_objs, int iif)
556{
557 if (ext_objs & BIT(ICMP_ERR_EXT_IIO_IIF))
558 icmp6_ext_iio_iif_append(net, skb, iif);
559}
560
561static struct sk_buff *
562icmp6_ext_append(struct net *net, struct sk_buff *skb_in,
563 struct icmp6hdr *icmp6h, unsigned int room, int iif)
564{
565 unsigned int payload_len, ext_max_len, ext_len;
566 struct icmp_ext_hdr *ext_hdr;
567 struct sk_buff *skb;
568 u8 ext_objs;
569 int nhoff;
570
571 switch (icmp6h->icmp6_type) {
572 case ICMPV6_DEST_UNREACH:
573 case ICMPV6_TIME_EXCEED:
574 break;
575 default:
576 return NULL;
577 }
578
579 /* Do not overwrite existing extensions. This can happen when we
580 * receive an ICMPv4 message with extensions from a tunnel and
581 * translate it to an ICMPv6 message towards an IPv6 host in the
582 * overlay network.
583 */
584 if (icmp6h->icmp6_datagram_len)
585 return NULL;
586
587 ext_objs = READ_ONCE(net->ipv6.sysctl.icmpv6_errors_extension_mask);
588 if (!ext_objs)
589 return NULL;
590
591 ext_max_len = icmp6_ext_max_len(ext_objs);
592 if (ICMP_EXT_ORIG_DGRAM_MIN_LEN + ext_max_len > room)
593 return NULL;
594
595 skb = skb_clone(skb_in, GFP_ATOMIC);
596 if (!skb)
597 return NULL;
598
599 nhoff = skb_network_offset(skb);
600 payload_len = min(skb->len - nhoff, ICMP_EXT_ORIG_DGRAM_MIN_LEN);
601
602 if (!pskb_network_may_pull(skb, payload_len))
603 goto free_skb;
604
605 if (pskb_trim(skb, nhoff + ICMP_EXT_ORIG_DGRAM_MIN_LEN) ||
606 __skb_put_padto(skb, nhoff + ICMP_EXT_ORIG_DGRAM_MIN_LEN, false))
607 goto free_skb;
608
609 if (pskb_expand_head(skb, 0, ext_max_len, GFP_ATOMIC))
610 goto free_skb;
611
612 ext_hdr = skb_put_zero(skb, sizeof(*ext_hdr));
613 ext_hdr->version = ICMP_EXT_VERSION_2;
614
615 icmp6_ext_objs_append(net, skb, ext_objs, iif);
616
617 /* Do not send an empty extension structure. */
618 ext_len = skb_tail_pointer(skb) - (unsigned char *)ext_hdr;
619 if (ext_len == sizeof(*ext_hdr))
620 goto free_skb;
621
622 ext_hdr->checksum = ip_compute_csum(ext_hdr, ext_len);
623 /* The length of the original datagram in 64-bit words (RFC 4884). */
624 icmp6h->icmp6_datagram_len = ICMP_EXT_ORIG_DGRAM_MIN_LEN / sizeof(u64);
625
626 return skb;
627
628free_skb:
629 consume_skb(skb);
630 return NULL;
631}
632
633/*
634 * Send an ICMP message in response to a packet in error
635 */
636void icmp6_send(struct sk_buff *skb, u8 type, u8 code, __u32 info,
637 const struct in6_addr *force_saddr,
638 const struct inet6_skb_parm *parm)
639{
640 struct inet6_dev *idev = NULL;
641 struct ipv6hdr *hdr = ipv6_hdr(skb);
642 struct sock *sk;
643 struct net *net;
644 struct ipv6_pinfo *np;
645 const struct in6_addr *saddr = NULL;
646 bool apply_ratelimit = false;
647 struct sk_buff *ext_skb;
648 struct dst_entry *dst;
649 unsigned int room;
650 struct icmp6hdr tmp_hdr;
651 struct flowi6 fl6;
652 struct icmpv6_msg msg;
653 struct ipcm6_cookie ipc6;
654 int iif = 0;
655 int addr_type = 0;
656 int len;
657 u32 mark;
658
659 if ((u8 *)hdr < skb->head ||
660 (skb_network_header(skb) + sizeof(*hdr)) > skb_tail_pointer(skb))
661 return;
662
663 if (!skb->dev)
664 return;
665
666 rcu_read_lock();
667
668 net = dev_net_rcu(skb->dev);
669 mark = IP6_REPLY_MARK(net, skb->mark);
670 /*
671 * Make sure we respect the rules
672 * i.e. RFC 1885 2.4(e)
673 * Rule (e.1) is enforced by not using icmp6_send
674 * in any code that processes icmp errors.
675 */
676 addr_type = ipv6_addr_type(&hdr->daddr);
677
678 if (ipv6_chk_addr(net, &hdr->daddr, skb->dev, 0) ||
679 ipv6_chk_acast_addr_src(net, skb->dev, &hdr->daddr))
680 saddr = &hdr->daddr;
681
682 /*
683 * Dest addr check
684 */
685
686 if (addr_type & IPV6_ADDR_MULTICAST || skb->pkt_type != PACKET_HOST) {
687 if (type != ICMPV6_PKT_TOOBIG &&
688 !(type == ICMPV6_PARAMPROB &&
689 code == ICMPV6_UNK_OPTION &&
690 (opt_unrec(skb, info))))
691 goto out;
692
693 saddr = NULL;
694 }
695
696 addr_type = ipv6_addr_type(&hdr->saddr);
697
698 /*
699 * Source addr check
700 */
701
702 if (__ipv6_addr_needs_scope_id(addr_type)) {
703 iif = icmp6_iif(skb);
704 } else {
705 /*
706 * The source device is used for looking up which routing table
707 * to use for sending an ICMP error.
708 */
709 iif = l3mdev_master_ifindex(skb->dev);
710 }
711
712 /*
713 * Must not send error if the source does not uniquely
714 * identify a single node (RFC2463 Section 2.4).
715 * We check unspecified / multicast addresses here,
716 * and anycast addresses will be checked later.
717 */
718 if ((addr_type == IPV6_ADDR_ANY) || (addr_type & IPV6_ADDR_MULTICAST)) {
719 net_dbg_ratelimited("icmp6_send: addr_any/mcast source [%pI6c > %pI6c]\n",
720 &hdr->saddr, &hdr->daddr);
721 goto out;
722 }
723
724 /*
725 * Never answer to a ICMP packet.
726 */
727 if (is_ineligible(skb)) {
728 net_dbg_ratelimited("icmp6_send: no reply to icmp error [%pI6c > %pI6c]\n",
729 &hdr->saddr, &hdr->daddr);
730 goto out;
731 }
732
733 /* Needed by both icmpv6_global_allow and icmpv6_xmit_lock */
734 local_bh_disable();
735
736 /* Check global sysctl_icmp_msgs_per_sec ratelimit */
737 if (!(skb->dev->flags & IFF_LOOPBACK) &&
738 !icmpv6_global_allow(net, type, &apply_ratelimit))
739 goto out_bh_enable;
740
741 mip6_addr_swap(skb, parm);
742
743 sk = icmpv6_xmit_lock(net);
744 if (!sk)
745 goto out_bh_enable;
746
747 memset(&fl6, 0, sizeof(fl6));
748 fl6.flowi6_proto = IPPROTO_ICMPV6;
749 fl6.daddr = hdr->saddr;
750 if (force_saddr)
751 saddr = force_saddr;
752 if (saddr) {
753 fl6.saddr = *saddr;
754 } else if (!icmpv6_rt_has_prefsrc(sk, type, &fl6)) {
755 /* select a more meaningful saddr from input if */
756 struct net_device *in_netdev;
757
758 in_netdev = dev_get_by_index(net, parm->iif);
759 if (in_netdev) {
760 ipv6_dev_get_saddr(net, in_netdev, &fl6.daddr,
761 inet6_sk(sk)->srcprefs,
762 &fl6.saddr);
763 dev_put(in_netdev);
764 }
765 }
766 fl6.flowi6_mark = mark;
767 fl6.flowi6_oif = iif;
768 fl6.fl6_icmp_type = type;
769 fl6.fl6_icmp_code = code;
770 fl6.flowi6_uid = sock_net_uid(net, NULL);
771 fl6.mp_hash = rt6_multipath_hash(net, &fl6, skb, NULL);
772 security_skb_classify_flow(skb, flowi6_to_flowi_common(&fl6));
773
774 np = inet6_sk(sk);
775
776 if (!icmpv6_xrlim_allow(sk, type, &fl6, apply_ratelimit))
777 goto out_unlock;
778
779 tmp_hdr.icmp6_type = type;
780 tmp_hdr.icmp6_code = code;
781 tmp_hdr.icmp6_cksum = 0;
782 tmp_hdr.icmp6_pointer = htonl(info);
783
784 if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr))
785 fl6.flowi6_oif = READ_ONCE(np->mcast_oif);
786 else if (!fl6.flowi6_oif)
787 fl6.flowi6_oif = READ_ONCE(np->ucast_oif);
788
789 ipcm6_init_sk(&ipc6, sk);
790 ipc6.sockc.mark = mark;
791 fl6.flowlabel = ip6_make_flowinfo(ipc6.tclass, fl6.flowlabel);
792
793 dst = icmpv6_route_lookup(net, skb, sk, &fl6);
794 if (IS_ERR(dst))
795 goto out_unlock;
796
797 ipc6.hlimit = ip6_sk_dst_hoplimit(np, &fl6, dst);
798
799 msg.skb = skb;
800 msg.offset = skb_network_offset(skb);
801 msg.type = type;
802
803 room = IPV6_MIN_MTU - sizeof(struct ipv6hdr) - sizeof(struct icmp6hdr);
804 ext_skb = icmp6_ext_append(net, skb, &tmp_hdr, room, parm->iif);
805 if (ext_skb)
806 msg.skb = ext_skb;
807
808 len = msg.skb->len - msg.offset;
809 len = min_t(unsigned int, len, room);
810 if (len < 0) {
811 net_dbg_ratelimited("icmp: len problem [%pI6c > %pI6c]\n",
812 &hdr->saddr, &hdr->daddr);
813 goto out_dst_release;
814 }
815
816 idev = __in6_dev_get(skb->dev);
817
818 if (ip6_append_data(sk, icmpv6_getfrag, &msg,
819 len + sizeof(struct icmp6hdr),
820 sizeof(struct icmp6hdr),
821 &ipc6, &fl6, dst_rt6_info(dst),
822 MSG_DONTWAIT)) {
823 ICMP6_INC_STATS(net, idev, ICMP6_MIB_OUTERRORS);
824 ip6_flush_pending_frames(sk);
825 } else {
826 icmpv6_push_pending_frames(sk, &fl6, &tmp_hdr,
827 len + sizeof(struct icmp6hdr));
828 }
829
830out_dst_release:
831 if (ext_skb)
832 consume_skb(ext_skb);
833 dst_release(dst);
834out_unlock:
835 icmpv6_xmit_unlock(sk);
836out_bh_enable:
837 local_bh_enable();
838out:
839 rcu_read_unlock();
840}
841EXPORT_SYMBOL(icmp6_send);
842
843/* Slightly more convenient version of icmp6_send with drop reasons.
844 */
845void icmpv6_param_prob_reason(struct sk_buff *skb, u8 code, int pos,
846 enum skb_drop_reason reason)
847{
848 icmp6_send(skb, ICMPV6_PARAMPROB, code, pos, NULL, IP6CB(skb));
849 kfree_skb_reason(skb, reason);
850}
851
852/* Generate icmpv6 with type/code ICMPV6_DEST_UNREACH/ICMPV6_ADDR_UNREACH
853 * if sufficient data bytes are available
854 * @nhs is the size of the tunnel header(s) :
855 * Either an IPv4 header for SIT encap
856 * an IPv4 header + GRE header for GRE encap
857 */
858int ip6_err_gen_icmpv6_unreach(struct sk_buff *skb, int nhs, int type,
859 unsigned int data_len)
860{
861 struct in6_addr temp_saddr;
862 struct rt6_info *rt;
863 struct sk_buff *skb2;
864 u32 info = 0;
865
866 if (!pskb_may_pull(skb, nhs + sizeof(struct ipv6hdr) + 8))
867 return 1;
868
869 /* RFC 4884 (partial) support for ICMP extensions */
870 if (data_len < 128 || (data_len & 7) || skb->len < data_len)
871 data_len = 0;
872
873 skb2 = data_len ? skb_copy(skb, GFP_ATOMIC) : skb_clone(skb, GFP_ATOMIC);
874
875 if (!skb2)
876 return 1;
877
878 /* Remove debris left by IPv4 stack. */
879 memset(IP6CB(skb2), 0, sizeof(*IP6CB(skb2)));
880
881 skb_dst_drop(skb2);
882 skb_pull(skb2, nhs);
883 skb_reset_network_header(skb2);
884
885 rt = rt6_lookup(dev_net_rcu(skb->dev), &ipv6_hdr(skb2)->saddr,
886 NULL, 0, skb, 0);
887
888 if (rt && rt->dst.dev)
889 skb2->dev = rt->dst.dev;
890
891 ipv6_addr_set_v4mapped(ip_hdr(skb)->saddr, &temp_saddr);
892
893 if (data_len) {
894 /* RFC 4884 (partial) support :
895 * insert 0 padding at the end, before the extensions
896 */
897 __skb_push(skb2, nhs);
898 skb_reset_network_header(skb2);
899 memmove(skb2->data, skb2->data + nhs, data_len - nhs);
900 memset(skb2->data + data_len - nhs, 0, nhs);
901 /* RFC 4884 4.5 : Length is measured in 64-bit words,
902 * and stored in reserved[0]
903 */
904 info = (data_len/8) << 24;
905 }
906 if (type == ICMP_TIME_EXCEEDED)
907 icmp6_send(skb2, ICMPV6_TIME_EXCEED, ICMPV6_EXC_HOPLIMIT,
908 info, &temp_saddr, IP6CB(skb2));
909 else
910 icmp6_send(skb2, ICMPV6_DEST_UNREACH, ICMPV6_ADDR_UNREACH,
911 info, &temp_saddr, IP6CB(skb2));
912 if (rt)
913 ip6_rt_put(rt);
914
915 kfree_skb(skb2);
916
917 return 0;
918}
919EXPORT_SYMBOL(ip6_err_gen_icmpv6_unreach);
920
921static enum skb_drop_reason icmpv6_echo_reply(struct sk_buff *skb)
922{
923 struct net *net = dev_net_rcu(skb->dev);
924 struct sock *sk;
925 struct inet6_dev *idev;
926 struct ipv6_pinfo *np;
927 const struct in6_addr *saddr = NULL;
928 struct icmp6hdr *icmph = icmp6_hdr(skb);
929 bool apply_ratelimit = false;
930 struct icmp6hdr tmp_hdr;
931 struct flowi6 fl6;
932 struct icmpv6_msg msg;
933 struct dst_entry *dst;
934 struct ipcm6_cookie ipc6;
935 u32 mark = IP6_REPLY_MARK(net, skb->mark);
936 SKB_DR(reason);
937 bool acast;
938 u8 type;
939
940 if (ipv6_addr_is_multicast(&ipv6_hdr(skb)->daddr) &&
941 net->ipv6.sysctl.icmpv6_echo_ignore_multicast)
942 return reason;
943
944 saddr = &ipv6_hdr(skb)->daddr;
945
946 acast = ipv6_anycast_destination(skb_dst(skb), saddr);
947 if (acast && net->ipv6.sysctl.icmpv6_echo_ignore_anycast)
948 return reason;
949
950 if (!ipv6_unicast_destination(skb) &&
951 !(net->ipv6.sysctl.anycast_src_echo_reply && acast))
952 saddr = NULL;
953
954 if (icmph->icmp6_type == ICMPV6_EXT_ECHO_REQUEST)
955 type = ICMPV6_EXT_ECHO_REPLY;
956 else
957 type = ICMPV6_ECHO_REPLY;
958
959 memcpy(&tmp_hdr, icmph, sizeof(tmp_hdr));
960 tmp_hdr.icmp6_type = type;
961
962 memset(&fl6, 0, sizeof(fl6));
963 if (READ_ONCE(net->ipv6.sysctl.flowlabel_reflect) &
964 FLOWLABEL_REFLECT_ICMPV6_ECHO_REPLIES)
965 fl6.flowlabel = ip6_flowlabel(ipv6_hdr(skb));
966
967 fl6.flowi6_proto = IPPROTO_ICMPV6;
968 fl6.daddr = ipv6_hdr(skb)->saddr;
969 if (saddr)
970 fl6.saddr = *saddr;
971 fl6.flowi6_oif = ipv6_addr_loopback(&fl6.daddr) ?
972 skb->dev->ifindex :
973 icmp6_iif(skb);
974 fl6.fl6_icmp_type = type;
975 fl6.flowi6_mark = mark;
976 fl6.flowi6_uid = sock_net_uid(net, NULL);
977 security_skb_classify_flow(skb, flowi6_to_flowi_common(&fl6));
978
979 local_bh_disable();
980 sk = icmpv6_xmit_lock(net);
981 if (!sk)
982 goto out_bh_enable;
983 np = inet6_sk(sk);
984
985 if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr))
986 fl6.flowi6_oif = READ_ONCE(np->mcast_oif);
987 else if (!fl6.flowi6_oif)
988 fl6.flowi6_oif = READ_ONCE(np->ucast_oif);
989
990 if (ip6_dst_lookup(net, sk, &dst, &fl6))
991 goto out;
992 dst = xfrm_lookup(net, dst, flowi6_to_flowi(&fl6), sk, 0);
993 if (IS_ERR(dst))
994 goto out;
995
996 /* Check the ratelimit */
997 if ((!(skb->dev->flags & IFF_LOOPBACK) &&
998 !icmpv6_global_allow(net, ICMPV6_ECHO_REPLY, &apply_ratelimit)) ||
999 !icmpv6_xrlim_allow(sk, ICMPV6_ECHO_REPLY, &fl6, apply_ratelimit))
1000 goto out_dst_release;
1001
1002 idev = __in6_dev_get(skb->dev);
1003
1004 msg.skb = skb;
1005 msg.offset = 0;
1006 msg.type = type;
1007
1008 ipcm6_init_sk(&ipc6, sk);
1009 ipc6.hlimit = ip6_sk_dst_hoplimit(np, &fl6, dst);
1010 ipc6.tclass = ipv6_get_dsfield(ipv6_hdr(skb));
1011 ipc6.sockc.mark = mark;
1012
1013 if (icmph->icmp6_type == ICMPV6_EXT_ECHO_REQUEST)
1014 if (!icmp_build_probe(skb, (struct icmphdr *)&tmp_hdr))
1015 goto out_dst_release;
1016
1017 if (ip6_append_data(sk, icmpv6_getfrag, &msg,
1018 skb->len + sizeof(struct icmp6hdr),
1019 sizeof(struct icmp6hdr), &ipc6, &fl6,
1020 dst_rt6_info(dst), MSG_DONTWAIT)) {
1021 __ICMP6_INC_STATS(net, idev, ICMP6_MIB_OUTERRORS);
1022 ip6_flush_pending_frames(sk);
1023 } else {
1024 icmpv6_push_pending_frames(sk, &fl6, &tmp_hdr,
1025 skb->len + sizeof(struct icmp6hdr));
1026 reason = SKB_CONSUMED;
1027 }
1028out_dst_release:
1029 dst_release(dst);
1030out:
1031 icmpv6_xmit_unlock(sk);
1032out_bh_enable:
1033 local_bh_enable();
1034 return reason;
1035}
1036
1037enum skb_drop_reason icmpv6_notify(struct sk_buff *skb, u8 type,
1038 u8 code, __be32 info)
1039{
1040 struct inet6_skb_parm *opt = IP6CB(skb);
1041 struct net *net = dev_net_rcu(skb->dev);
1042 const struct inet6_protocol *ipprot;
1043 enum skb_drop_reason reason;
1044 int inner_offset;
1045 __be16 frag_off;
1046 u8 nexthdr;
1047
1048 reason = pskb_may_pull_reason(skb, sizeof(struct ipv6hdr));
1049 if (reason != SKB_NOT_DROPPED_YET)
1050 goto out;
1051
1052 seg6_icmp_srh(skb, opt);
1053
1054 nexthdr = ((struct ipv6hdr *)skb->data)->nexthdr;
1055 if (ipv6_ext_hdr(nexthdr)) {
1056 /* now skip over extension headers */
1057 inner_offset = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr),
1058 &nexthdr, &frag_off);
1059 if (inner_offset < 0) {
1060 SKB_DR_SET(reason, IPV6_BAD_EXTHDR);
1061 goto out;
1062 }
1063 } else {
1064 inner_offset = sizeof(struct ipv6hdr);
1065 }
1066
1067 /* Checkin header including 8 bytes of inner protocol header. */
1068 reason = pskb_may_pull_reason(skb, inner_offset + 8);
1069 if (reason != SKB_NOT_DROPPED_YET)
1070 goto out;
1071
1072 if (nexthdr == IPPROTO_RAW) {
1073 /* Add a more specific reason later ? */
1074 reason = SKB_DROP_REASON_NOT_SPECIFIED;
1075 goto out;
1076 }
1077
1078 /* BUGGG_FUTURE: we should try to parse exthdrs in this packet.
1079 Without this we will not able f.e. to make source routed
1080 pmtu discovery.
1081 Corresponding argument (opt) to notifiers is already added.
1082 --ANK (980726)
1083 */
1084
1085 ipprot = rcu_dereference(inet6_protos[nexthdr]);
1086 if (ipprot && ipprot->err_handler)
1087 ipprot->err_handler(skb, opt, type, code, inner_offset, info);
1088
1089 raw6_icmp_error(skb, nexthdr, type, code, inner_offset, info);
1090 return SKB_CONSUMED;
1091
1092out:
1093 __ICMP6_INC_STATS(net, __in6_dev_get(skb->dev), ICMP6_MIB_INERRORS);
1094 return reason;
1095}
1096
1097/*
1098 * Handle icmp messages
1099 */
1100
1101static int icmpv6_rcv(struct sk_buff *skb)
1102{
1103 enum skb_drop_reason reason = SKB_DROP_REASON_NOT_SPECIFIED;
1104 struct net *net = dev_net_rcu(skb->dev);
1105 struct net_device *dev = icmp6_dev(skb);
1106 struct inet6_dev *idev = __in6_dev_get(dev);
1107 struct icmp6hdr *hdr;
1108 u8 type;
1109
1110 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) {
1111 struct sec_path *sp = skb_sec_path(skb);
1112 int nh;
1113
1114 if (!(sp && sp->xvec[sp->len - 1]->props.flags &
1115 XFRM_STATE_ICMP)) {
1116 reason = SKB_DROP_REASON_XFRM_POLICY;
1117 goto drop_no_count;
1118 }
1119
1120 if (!pskb_may_pull(skb, sizeof(*hdr) + sizeof(struct ipv6hdr)))
1121 goto drop_no_count;
1122
1123 nh = skb_network_offset(skb);
1124 skb_set_network_header(skb, sizeof(*hdr));
1125
1126 if (!xfrm6_policy_check_reverse(NULL, XFRM_POLICY_IN,
1127 skb)) {
1128 reason = SKB_DROP_REASON_XFRM_POLICY;
1129 goto drop_no_count;
1130 }
1131
1132 skb_set_network_header(skb, nh);
1133 }
1134
1135 __ICMP6_INC_STATS(dev_net_rcu(dev), idev, ICMP6_MIB_INMSGS);
1136
1137 if (skb_checksum_validate(skb, IPPROTO_ICMPV6, ip6_compute_pseudo)) {
1138 net_dbg_ratelimited("ICMPv6 checksum failed [%pI6c > %pI6c]\n",
1139 &ipv6_hdr(skb)->saddr,
1140 &ipv6_hdr(skb)->daddr);
1141 goto csum_error;
1142 }
1143
1144 if (!pskb_pull(skb, sizeof(*hdr)))
1145 goto discard_it;
1146
1147 hdr = icmp6_hdr(skb);
1148
1149 type = hdr->icmp6_type;
1150
1151 ICMP6MSGIN_INC_STATS(dev_net_rcu(dev), idev, type);
1152
1153 switch (type) {
1154 case ICMPV6_ECHO_REQUEST:
1155 if (!net->ipv6.sysctl.icmpv6_echo_ignore_all)
1156 reason = icmpv6_echo_reply(skb);
1157 break;
1158 case ICMPV6_EXT_ECHO_REQUEST:
1159 if (!net->ipv6.sysctl.icmpv6_echo_ignore_all &&
1160 READ_ONCE(net->ipv4.sysctl_icmp_echo_enable_probe))
1161 reason = icmpv6_echo_reply(skb);
1162 break;
1163
1164 case ICMPV6_ECHO_REPLY:
1165 case ICMPV6_EXT_ECHO_REPLY:
1166 ping_rcv(skb);
1167 return 0;
1168
1169 case ICMPV6_PKT_TOOBIG:
1170 /* BUGGG_FUTURE: if packet contains rthdr, we cannot update
1171 standard destination cache. Seems, only "advanced"
1172 destination cache will allow to solve this problem
1173 --ANK (980726)
1174 */
1175 if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
1176 goto discard_it;
1177 hdr = icmp6_hdr(skb);
1178
1179 /* to notify */
1180 fallthrough;
1181 case ICMPV6_DEST_UNREACH:
1182 case ICMPV6_TIME_EXCEED:
1183 case ICMPV6_PARAMPROB:
1184 reason = icmpv6_notify(skb, type, hdr->icmp6_code,
1185 hdr->icmp6_mtu);
1186 break;
1187
1188 case NDISC_ROUTER_SOLICITATION:
1189 case NDISC_ROUTER_ADVERTISEMENT:
1190 case NDISC_NEIGHBOUR_SOLICITATION:
1191 case NDISC_NEIGHBOUR_ADVERTISEMENT:
1192 case NDISC_REDIRECT:
1193 reason = ndisc_rcv(skb);
1194 break;
1195
1196 case ICMPV6_MGM_QUERY:
1197 igmp6_event_query(skb);
1198 return 0;
1199
1200 case ICMPV6_MGM_REPORT:
1201 igmp6_event_report(skb);
1202 return 0;
1203
1204 case ICMPV6_MGM_REDUCTION:
1205 case ICMPV6_NI_QUERY:
1206 case ICMPV6_NI_REPLY:
1207 case ICMPV6_MLD2_REPORT:
1208 case ICMPV6_DHAAD_REQUEST:
1209 case ICMPV6_DHAAD_REPLY:
1210 case ICMPV6_MOBILE_PREFIX_SOL:
1211 case ICMPV6_MOBILE_PREFIX_ADV:
1212 break;
1213
1214 default:
1215 /* informational */
1216 if (type & ICMPV6_INFOMSG_MASK)
1217 break;
1218
1219 net_dbg_ratelimited("icmpv6: msg of unknown type [%pI6c > %pI6c]\n",
1220 &ipv6_hdr(skb)->saddr,
1221 &ipv6_hdr(skb)->daddr);
1222
1223 /*
1224 * error of unknown type.
1225 * must pass to upper level
1226 */
1227
1228 reason = icmpv6_notify(skb, type, hdr->icmp6_code,
1229 hdr->icmp6_mtu);
1230 }
1231
1232 /* until the v6 path can be better sorted assume failure and
1233 * preserve the status quo behaviour for the rest of the paths to here
1234 */
1235 if (reason)
1236 kfree_skb_reason(skb, reason);
1237 else
1238 consume_skb(skb);
1239
1240 return 0;
1241
1242csum_error:
1243 reason = SKB_DROP_REASON_ICMP_CSUM;
1244 __ICMP6_INC_STATS(dev_net_rcu(dev), idev, ICMP6_MIB_CSUMERRORS);
1245discard_it:
1246 __ICMP6_INC_STATS(dev_net_rcu(dev), idev, ICMP6_MIB_INERRORS);
1247drop_no_count:
1248 kfree_skb_reason(skb, reason);
1249 return 0;
1250}
1251
1252void icmpv6_flow_init(const struct sock *sk, struct flowi6 *fl6, u8 type,
1253 const struct in6_addr *saddr,
1254 const struct in6_addr *daddr, int oif)
1255{
1256 memset(fl6, 0, sizeof(*fl6));
1257 fl6->saddr = *saddr;
1258 fl6->daddr = *daddr;
1259 fl6->flowi6_proto = IPPROTO_ICMPV6;
1260 fl6->fl6_icmp_type = type;
1261 fl6->fl6_icmp_code = 0;
1262 fl6->flowi6_oif = oif;
1263 security_sk_classify_flow(sk, flowi6_to_flowi_common(fl6));
1264}
1265
1266int __init icmpv6_init(void)
1267{
1268 struct sock *sk;
1269 int err, i;
1270
1271 for_each_possible_cpu(i) {
1272 err = inet_ctl_sock_create(&sk, PF_INET6,
1273 SOCK_RAW, IPPROTO_ICMPV6, &init_net);
1274 if (err < 0) {
1275 pr_err("Failed to initialize the ICMP6 control socket (err %d)\n",
1276 err);
1277 return err;
1278 }
1279
1280 per_cpu(ipv6_icmp_sk, i) = sk;
1281
1282 /* Enough space for 2 64K ICMP packets, including
1283 * sk_buff struct overhead.
1284 */
1285 sk->sk_sndbuf = 2 * SKB_TRUESIZE(64 * 1024);
1286 }
1287
1288 err = -EAGAIN;
1289 if (inet6_add_protocol(&icmpv6_protocol, IPPROTO_ICMPV6) < 0)
1290 goto fail;
1291
1292 return 0;
1293
1294fail:
1295 pr_err("Failed to register ICMP6 protocol\n");
1296 return err;
1297}
1298
1299void icmpv6_cleanup(void)
1300{
1301 inet6_del_protocol(&icmpv6_protocol, IPPROTO_ICMPV6);
1302}
1303
1304
1305static const struct icmp6_err {
1306 int err;
1307 int fatal;
1308} tab_unreach[] = {
1309 { /* NOROUTE */
1310 .err = ENETUNREACH,
1311 .fatal = 0,
1312 },
1313 { /* ADM_PROHIBITED */
1314 .err = EACCES,
1315 .fatal = 1,
1316 },
1317 { /* Was NOT_NEIGHBOUR, now reserved */
1318 .err = EHOSTUNREACH,
1319 .fatal = 0,
1320 },
1321 { /* ADDR_UNREACH */
1322 .err = EHOSTUNREACH,
1323 .fatal = 0,
1324 },
1325 { /* PORT_UNREACH */
1326 .err = ECONNREFUSED,
1327 .fatal = 1,
1328 },
1329 { /* POLICY_FAIL */
1330 .err = EACCES,
1331 .fatal = 1,
1332 },
1333 { /* REJECT_ROUTE */
1334 .err = EACCES,
1335 .fatal = 1,
1336 },
1337};
1338
1339int icmpv6_err_convert(u8 type, u8 code, int *err)
1340{
1341 int fatal = 0;
1342
1343 *err = EPROTO;
1344
1345 switch (type) {
1346 case ICMPV6_DEST_UNREACH:
1347 fatal = 1;
1348 if (code < ARRAY_SIZE(tab_unreach)) {
1349 *err = tab_unreach[code].err;
1350 fatal = tab_unreach[code].fatal;
1351 }
1352 break;
1353
1354 case ICMPV6_PKT_TOOBIG:
1355 *err = EMSGSIZE;
1356 break;
1357
1358 case ICMPV6_PARAMPROB:
1359 *err = EPROTO;
1360 fatal = 1;
1361 break;
1362
1363 case ICMPV6_TIME_EXCEED:
1364 *err = EHOSTUNREACH;
1365 break;
1366 }
1367
1368 return fatal;
1369}
1370EXPORT_SYMBOL(icmpv6_err_convert);
1371
1372#ifdef CONFIG_SYSCTL
1373
1374static u32 icmpv6_errors_extension_mask_all =
1375 GENMASK_U8(ICMP_ERR_EXT_COUNT - 1, 0);
1376
1377static const struct ctl_table ipv6_icmp_table_template[] = {
1378 {
1379 .procname = "ratelimit",
1380 .data = &init_net.ipv6.sysctl.icmpv6_time,
1381 .maxlen = sizeof(int),
1382 .mode = 0644,
1383 .proc_handler = proc_dointvec_ms_jiffies,
1384 },
1385 {
1386 .procname = "echo_ignore_all",
1387 .data = &init_net.ipv6.sysctl.icmpv6_echo_ignore_all,
1388 .maxlen = sizeof(u8),
1389 .mode = 0644,
1390 .proc_handler = proc_dou8vec_minmax,
1391 },
1392 {
1393 .procname = "echo_ignore_multicast",
1394 .data = &init_net.ipv6.sysctl.icmpv6_echo_ignore_multicast,
1395 .maxlen = sizeof(u8),
1396 .mode = 0644,
1397 .proc_handler = proc_dou8vec_minmax,
1398 },
1399 {
1400 .procname = "echo_ignore_anycast",
1401 .data = &init_net.ipv6.sysctl.icmpv6_echo_ignore_anycast,
1402 .maxlen = sizeof(u8),
1403 .mode = 0644,
1404 .proc_handler = proc_dou8vec_minmax,
1405 },
1406 {
1407 .procname = "ratemask",
1408 .data = &init_net.ipv6.sysctl.icmpv6_ratemask_ptr,
1409 .maxlen = ICMPV6_MSG_MAX + 1,
1410 .mode = 0644,
1411 .proc_handler = proc_do_large_bitmap,
1412 },
1413 {
1414 .procname = "error_anycast_as_unicast",
1415 .data = &init_net.ipv6.sysctl.icmpv6_error_anycast_as_unicast,
1416 .maxlen = sizeof(u8),
1417 .mode = 0644,
1418 .proc_handler = proc_dou8vec_minmax,
1419 .extra1 = SYSCTL_ZERO,
1420 .extra2 = SYSCTL_ONE,
1421 },
1422 {
1423 .procname = "errors_extension_mask",
1424 .data = &init_net.ipv6.sysctl.icmpv6_errors_extension_mask,
1425 .maxlen = sizeof(u8),
1426 .mode = 0644,
1427 .proc_handler = proc_dou8vec_minmax,
1428 .extra1 = SYSCTL_ZERO,
1429 .extra2 = &icmpv6_errors_extension_mask_all,
1430 },
1431};
1432
1433struct ctl_table * __net_init ipv6_icmp_sysctl_init(struct net *net)
1434{
1435 struct ctl_table *table;
1436
1437 table = kmemdup(ipv6_icmp_table_template,
1438 sizeof(ipv6_icmp_table_template),
1439 GFP_KERNEL);
1440
1441 if (table) {
1442 table[0].data = &net->ipv6.sysctl.icmpv6_time;
1443 table[1].data = &net->ipv6.sysctl.icmpv6_echo_ignore_all;
1444 table[2].data = &net->ipv6.sysctl.icmpv6_echo_ignore_multicast;
1445 table[3].data = &net->ipv6.sysctl.icmpv6_echo_ignore_anycast;
1446 table[4].data = &net->ipv6.sysctl.icmpv6_ratemask_ptr;
1447 table[5].data = &net->ipv6.sysctl.icmpv6_error_anycast_as_unicast;
1448 table[6].data = &net->ipv6.sysctl.icmpv6_errors_extension_mask;
1449 }
1450 return table;
1451}
1452
1453size_t ipv6_icmp_sysctl_table_size(void)
1454{
1455 return ARRAY_SIZE(ipv6_icmp_table_template);
1456}
1457#endif