]>
Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * Internet Control Message Protocol (ICMPv6) | |
3 | * Linux INET6 implementation | |
4 | * | |
5 | * Authors: | |
6 | * Pedro Roque <roque@di.fc.ul.pt> | |
7 | * | |
1da177e4 LT |
8 | * Based on net/ipv4/icmp.c |
9 | * | |
10 | * RFC 1885 | |
11 | * | |
12 | * This program is free software; you can redistribute it and/or | |
13 | * modify it under the terms of the GNU General Public License | |
14 | * as published by the Free Software Foundation; either version | |
15 | * 2 of the License, or (at your option) any later version. | |
16 | */ | |
17 | ||
18 | /* | |
19 | * Changes: | |
20 | * | |
21 | * Andi Kleen : exception handling | |
22 | * Andi Kleen add rate limits. never reply to a icmp. | |
23 | * add more length checks and other fixes. | |
24 | * yoshfuji : ensure to sent parameter problem for | |
25 | * fragments. | |
26 | * YOSHIFUJI Hideaki @USAGI: added sysctl for icmp rate limit. | |
27 | * Randy Dunlap and | |
28 | * YOSHIFUJI Hideaki @USAGI: Per-interface statistics support | |
29 | * Kazunori MIYAZAWA @USAGI: change output process to use ip6_append_data | |
30 | */ | |
31 | ||
32 | #include <linux/module.h> | |
33 | #include <linux/errno.h> | |
34 | #include <linux/types.h> | |
35 | #include <linux/socket.h> | |
36 | #include <linux/in.h> | |
37 | #include <linux/kernel.h> | |
1da177e4 LT |
38 | #include <linux/sockios.h> |
39 | #include <linux/net.h> | |
40 | #include <linux/skbuff.h> | |
41 | #include <linux/init.h> | |
763ecff1 | 42 | #include <linux/netfilter.h> |
5a0e3ad6 | 43 | #include <linux/slab.h> |
1da177e4 LT |
44 | |
45 | #ifdef CONFIG_SYSCTL | |
46 | #include <linux/sysctl.h> | |
47 | #endif | |
48 | ||
49 | #include <linux/inet.h> | |
50 | #include <linux/netdevice.h> | |
51 | #include <linux/icmpv6.h> | |
52 | ||
53 | #include <net/ip.h> | |
54 | #include <net/sock.h> | |
55 | ||
56 | #include <net/ipv6.h> | |
57 | #include <net/ip6_checksum.h> | |
58 | #include <net/protocol.h> | |
59 | #include <net/raw.h> | |
60 | #include <net/rawv6.h> | |
61 | #include <net/transp_v6.h> | |
62 | #include <net/ip6_route.h> | |
63 | #include <net/addrconf.h> | |
64 | #include <net/icmp.h> | |
8b7817f3 | 65 | #include <net/xfrm.h> |
1ed8516f | 66 | #include <net/inet_common.h> |
1da177e4 LT |
67 | |
68 | #include <asm/uaccess.h> | |
69 | #include <asm/system.h> | |
70 | ||
1da177e4 LT |
71 | /* |
72 | * The ICMP socket(s). This is the most convenient way to flow control | |
73 | * our ICMP output as well as maintain a clean interface throughout | |
74 | * all layers. All Socketless IP sends will soon be gone. | |
75 | * | |
76 | * On SMP we have one ICMP socket per-cpu. | |
77 | */ | |
98c6d1b2 DL |
78 | static inline struct sock *icmpv6_sk(struct net *net) |
79 | { | |
80 | return net->ipv6.icmp_sk[smp_processor_id()]; | |
81 | } | |
1da177e4 | 82 | |
e5bbef20 | 83 | static int icmpv6_rcv(struct sk_buff *skb); |
1da177e4 | 84 | |
41135cc8 | 85 | static const struct inet6_protocol icmpv6_protocol = { |
1da177e4 | 86 | .handler = icmpv6_rcv, |
8b7817f3 | 87 | .flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL, |
1da177e4 LT |
88 | }; |
89 | ||
fdc0bde9 | 90 | static __inline__ struct sock *icmpv6_xmit_lock(struct net *net) |
1da177e4 | 91 | { |
fdc0bde9 DL |
92 | struct sock *sk; |
93 | ||
1da177e4 LT |
94 | local_bh_disable(); |
95 | ||
fdc0bde9 | 96 | sk = icmpv6_sk(net); |
405666db | 97 | if (unlikely(!spin_trylock(&sk->sk_lock.slock))) { |
1da177e4 LT |
98 | /* This can happen if the output path (f.e. SIT or |
99 | * ip6ip6 tunnel) signals dst_link_failure() for an | |
100 | * outgoing ICMP6 packet. | |
101 | */ | |
102 | local_bh_enable(); | |
fdc0bde9 | 103 | return NULL; |
1da177e4 | 104 | } |
fdc0bde9 | 105 | return sk; |
1da177e4 LT |
106 | } |
107 | ||
405666db | 108 | static __inline__ void icmpv6_xmit_unlock(struct sock *sk) |
1da177e4 | 109 | { |
405666db | 110 | spin_unlock_bh(&sk->sk_lock.slock); |
1da177e4 LT |
111 | } |
112 | ||
1ab1457c | 113 | /* |
1da177e4 LT |
114 | * Slightly more convenient version of icmpv6_send. |
115 | */ | |
d5fdd6ba | 116 | void icmpv6_param_prob(struct sk_buff *skb, u8 code, int pos) |
1da177e4 | 117 | { |
3ffe533c | 118 | icmpv6_send(skb, ICMPV6_PARAMPROB, code, pos); |
1da177e4 LT |
119 | kfree_skb(skb); |
120 | } | |
121 | ||
122 | /* | |
123 | * Figure out, may we reply to this packet with icmp error. | |
124 | * | |
125 | * We do not reply, if: | |
126 | * - it was icmp error message. | |
127 | * - it is truncated, so that it is known, that protocol is ICMPV6 | |
128 | * (i.e. in the middle of some exthdr) | |
129 | * | |
130 | * --ANK (980726) | |
131 | */ | |
132 | ||
133 | static int is_ineligible(struct sk_buff *skb) | |
134 | { | |
0660e03f | 135 | int ptr = (u8 *)(ipv6_hdr(skb) + 1) - skb->data; |
1da177e4 | 136 | int len = skb->len - ptr; |
0660e03f | 137 | __u8 nexthdr = ipv6_hdr(skb)->nexthdr; |
1da177e4 LT |
138 | |
139 | if (len < 0) | |
140 | return 1; | |
141 | ||
0d3d077c | 142 | ptr = ipv6_skip_exthdr(skb, ptr, &nexthdr); |
1da177e4 LT |
143 | if (ptr < 0) |
144 | return 0; | |
145 | if (nexthdr == IPPROTO_ICMPV6) { | |
146 | u8 _type, *tp; | |
147 | tp = skb_header_pointer(skb, | |
148 | ptr+offsetof(struct icmp6hdr, icmp6_type), | |
149 | sizeof(_type), &_type); | |
150 | if (tp == NULL || | |
151 | !(*tp & ICMPV6_INFOMSG_MASK)) | |
152 | return 1; | |
153 | } | |
154 | return 0; | |
155 | } | |
156 | ||
1ab1457c YH |
157 | /* |
158 | * Check the ICMP output rate limit | |
1da177e4 | 159 | */ |
d5fdd6ba | 160 | static inline int icmpv6_xrlim_allow(struct sock *sk, u8 type, |
1da177e4 LT |
161 | struct flowi *fl) |
162 | { | |
163 | struct dst_entry *dst; | |
3b1e0a65 | 164 | struct net *net = sock_net(sk); |
1da177e4 LT |
165 | int res = 0; |
166 | ||
167 | /* Informational messages are not limited. */ | |
168 | if (type & ICMPV6_INFOMSG_MASK) | |
169 | return 1; | |
170 | ||
171 | /* Do not limit pmtu discovery, it would break it. */ | |
172 | if (type == ICMPV6_PKT_TOOBIG) | |
173 | return 1; | |
174 | ||
1ab1457c | 175 | /* |
1da177e4 LT |
176 | * Look up the output route. |
177 | * XXX: perhaps the expire for routing entries cloned by | |
178 | * this lookup should be more aggressive (not longer than timeout). | |
179 | */ | |
9a43b709 | 180 | dst = ip6_route_output(net, sk, fl); |
1da177e4 | 181 | if (dst->error) { |
3bd653c8 | 182 | IP6_INC_STATS(net, ip6_dst_idev(dst), |
a11d206d | 183 | IPSTATS_MIB_OUTNOROUTES); |
1da177e4 LT |
184 | } else if (dst->dev && (dst->dev->flags&IFF_LOOPBACK)) { |
185 | res = 1; | |
186 | } else { | |
187 | struct rt6_info *rt = (struct rt6_info *)dst; | |
9a43b709 | 188 | int tmo = net->ipv6.sysctl.icmpv6_time; |
1da177e4 LT |
189 | |
190 | /* Give more bandwidth to wider prefixes. */ | |
191 | if (rt->rt6i_dst.plen < 128) | |
192 | tmo >>= ((128 - rt->rt6i_dst.plen)>>5); | |
193 | ||
194 | res = xrlim_allow(dst, tmo); | |
195 | } | |
196 | dst_release(dst); | |
197 | return res; | |
198 | } | |
199 | ||
200 | /* | |
201 | * an inline helper for the "simple" if statement below | |
202 | * checks if parameter problem report is caused by an | |
1ab1457c | 203 | * unrecognized IPv6 option that has the Option Type |
1da177e4 LT |
204 | * highest-order two bits set to 10 |
205 | */ | |
206 | ||
207 | static __inline__ int opt_unrec(struct sk_buff *skb, __u32 offset) | |
208 | { | |
209 | u8 _optval, *op; | |
210 | ||
bbe735e4 | 211 | offset += skb_network_offset(skb); |
1da177e4 LT |
212 | op = skb_header_pointer(skb, offset, sizeof(_optval), &_optval); |
213 | if (op == NULL) | |
214 | return 1; | |
215 | return (*op & 0xC0) == 0x80; | |
216 | } | |
217 | ||
218 | static int icmpv6_push_pending_frames(struct sock *sk, struct flowi *fl, struct icmp6hdr *thdr, int len) | |
219 | { | |
220 | struct sk_buff *skb; | |
221 | struct icmp6hdr *icmp6h; | |
222 | int err = 0; | |
223 | ||
224 | if ((skb = skb_peek(&sk->sk_write_queue)) == NULL) | |
225 | goto out; | |
226 | ||
cc70ab26 | 227 | icmp6h = icmp6_hdr(skb); |
1da177e4 LT |
228 | memcpy(icmp6h, thdr, sizeof(struct icmp6hdr)); |
229 | icmp6h->icmp6_cksum = 0; | |
230 | ||
231 | if (skb_queue_len(&sk->sk_write_queue) == 1) { | |
07f0757a | 232 | skb->csum = csum_partial(icmp6h, |
1da177e4 LT |
233 | sizeof(struct icmp6hdr), skb->csum); |
234 | icmp6h->icmp6_cksum = csum_ipv6_magic(&fl->fl6_src, | |
235 | &fl->fl6_dst, | |
236 | len, fl->proto, | |
237 | skb->csum); | |
238 | } else { | |
868c86bc | 239 | __wsum tmp_csum = 0; |
1da177e4 LT |
240 | |
241 | skb_queue_walk(&sk->sk_write_queue, skb) { | |
242 | tmp_csum = csum_add(tmp_csum, skb->csum); | |
243 | } | |
244 | ||
07f0757a | 245 | tmp_csum = csum_partial(icmp6h, |
1da177e4 | 246 | sizeof(struct icmp6hdr), tmp_csum); |
868c86bc AV |
247 | icmp6h->icmp6_cksum = csum_ipv6_magic(&fl->fl6_src, |
248 | &fl->fl6_dst, | |
249 | len, fl->proto, | |
250 | tmp_csum); | |
1da177e4 | 251 | } |
1da177e4 LT |
252 | ip6_push_pending_frames(sk); |
253 | out: | |
254 | return err; | |
255 | } | |
256 | ||
257 | struct icmpv6_msg { | |
258 | struct sk_buff *skb; | |
259 | int offset; | |
763ecff1 | 260 | uint8_t type; |
1da177e4 LT |
261 | }; |
262 | ||
263 | static int icmpv6_getfrag(void *from, char *to, int offset, int len, int odd, struct sk_buff *skb) | |
264 | { | |
265 | struct icmpv6_msg *msg = (struct icmpv6_msg *) from; | |
266 | struct sk_buff *org_skb = msg->skb; | |
5f92a738 | 267 | __wsum csum = 0; |
1da177e4 LT |
268 | |
269 | csum = skb_copy_and_csum_bits(org_skb, msg->offset + offset, | |
270 | to, len, csum); | |
271 | skb->csum = csum_block_add(skb->csum, csum, odd); | |
763ecff1 YK |
272 | if (!(msg->type & ICMPV6_INFOMSG_MASK)) |
273 | nf_ct_attach(skb, org_skb); | |
1da177e4 LT |
274 | return 0; |
275 | } | |
276 | ||
59fbb3a6 | 277 | #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE) |
79383236 MN |
278 | static void mip6_addr_swap(struct sk_buff *skb) |
279 | { | |
0660e03f | 280 | struct ipv6hdr *iph = ipv6_hdr(skb); |
79383236 MN |
281 | struct inet6_skb_parm *opt = IP6CB(skb); |
282 | struct ipv6_destopt_hao *hao; | |
283 | struct in6_addr tmp; | |
284 | int off; | |
285 | ||
286 | if (opt->dsthao) { | |
287 | off = ipv6_find_tlv(skb, opt->dsthao, IPV6_TLV_HAO); | |
288 | if (likely(off >= 0)) { | |
d56f90a7 ACM |
289 | hao = (struct ipv6_destopt_hao *) |
290 | (skb_network_header(skb) + off); | |
79383236 MN |
291 | ipv6_addr_copy(&tmp, &iph->saddr); |
292 | ipv6_addr_copy(&iph->saddr, &hao->addr); | |
293 | ipv6_addr_copy(&hao->addr, &tmp); | |
294 | } | |
295 | } | |
296 | } | |
297 | #else | |
298 | static inline void mip6_addr_swap(struct sk_buff *skb) {} | |
299 | #endif | |
300 | ||
1da177e4 LT |
301 | /* |
302 | * Send an ICMP message in response to a packet in error | |
303 | */ | |
3ffe533c | 304 | void icmpv6_send(struct sk_buff *skb, u8 type, u8 code, __u32 info) |
1da177e4 | 305 | { |
c346dca1 | 306 | struct net *net = dev_net(skb->dev); |
1da177e4 | 307 | struct inet6_dev *idev = NULL; |
0660e03f | 308 | struct ipv6hdr *hdr = ipv6_hdr(skb); |
84427d53 YH |
309 | struct sock *sk; |
310 | struct ipv6_pinfo *np; | |
1da177e4 LT |
311 | struct in6_addr *saddr = NULL; |
312 | struct dst_entry *dst; | |
8b7817f3 | 313 | struct dst_entry *dst2; |
1da177e4 LT |
314 | struct icmp6hdr tmp_hdr; |
315 | struct flowi fl; | |
8b7817f3 | 316 | struct flowi fl2; |
1da177e4 LT |
317 | struct icmpv6_msg msg; |
318 | int iif = 0; | |
319 | int addr_type = 0; | |
320 | int len; | |
e651f03a | 321 | int hlimit; |
1da177e4 LT |
322 | int err = 0; |
323 | ||
27a884dc ACM |
324 | if ((u8 *)hdr < skb->head || |
325 | (skb->network_header + sizeof(*hdr)) > skb->tail) | |
1da177e4 LT |
326 | return; |
327 | ||
328 | /* | |
1ab1457c | 329 | * Make sure we respect the rules |
1da177e4 LT |
330 | * i.e. RFC 1885 2.4(e) |
331 | * Rule (e.1) is enforced by not using icmpv6_send | |
332 | * in any code that processes icmp errors. | |
333 | */ | |
334 | addr_type = ipv6_addr_type(&hdr->daddr); | |
335 | ||
9a43b709 | 336 | if (ipv6_chk_addr(net, &hdr->daddr, skb->dev, 0)) |
1da177e4 LT |
337 | saddr = &hdr->daddr; |
338 | ||
339 | /* | |
340 | * Dest addr check | |
341 | */ | |
342 | ||
343 | if ((addr_type & IPV6_ADDR_MULTICAST || skb->pkt_type != PACKET_HOST)) { | |
344 | if (type != ICMPV6_PKT_TOOBIG && | |
1ab1457c YH |
345 | !(type == ICMPV6_PARAMPROB && |
346 | code == ICMPV6_UNK_OPTION && | |
1da177e4 LT |
347 | (opt_unrec(skb, info)))) |
348 | return; | |
349 | ||
350 | saddr = NULL; | |
351 | } | |
352 | ||
353 | addr_type = ipv6_addr_type(&hdr->saddr); | |
354 | ||
355 | /* | |
356 | * Source addr check | |
357 | */ | |
358 | ||
359 | if (addr_type & IPV6_ADDR_LINKLOCAL) | |
360 | iif = skb->dev->ifindex; | |
361 | ||
362 | /* | |
8de3351e YH |
363 | * Must not send error if the source does not uniquely |
364 | * identify a single node (RFC2463 Section 2.4). | |
365 | * We check unspecified / multicast addresses here, | |
366 | * and anycast addresses will be checked later. | |
1da177e4 LT |
367 | */ |
368 | if ((addr_type == IPV6_ADDR_ANY) || (addr_type & IPV6_ADDR_MULTICAST)) { | |
64ce2073 | 369 | LIMIT_NETDEBUG(KERN_DEBUG "icmpv6_send: addr_any/mcast source\n"); |
1da177e4 LT |
370 | return; |
371 | } | |
372 | ||
1ab1457c | 373 | /* |
1da177e4 LT |
374 | * Never answer to a ICMP packet. |
375 | */ | |
376 | if (is_ineligible(skb)) { | |
64ce2073 | 377 | LIMIT_NETDEBUG(KERN_DEBUG "icmpv6_send: no reply to icmp error\n"); |
1da177e4 LT |
378 | return; |
379 | } | |
380 | ||
79383236 MN |
381 | mip6_addr_swap(skb); |
382 | ||
1da177e4 LT |
383 | memset(&fl, 0, sizeof(fl)); |
384 | fl.proto = IPPROTO_ICMPV6; | |
385 | ipv6_addr_copy(&fl.fl6_dst, &hdr->saddr); | |
386 | if (saddr) | |
387 | ipv6_addr_copy(&fl.fl6_src, saddr); | |
388 | fl.oif = iif; | |
389 | fl.fl_icmp_type = type; | |
390 | fl.fl_icmp_code = code; | |
beb8d13b | 391 | security_skb_classify_flow(skb, &fl); |
1da177e4 | 392 | |
fdc0bde9 DL |
393 | sk = icmpv6_xmit_lock(net); |
394 | if (sk == NULL) | |
405666db | 395 | return; |
fdc0bde9 | 396 | np = inet6_sk(sk); |
405666db | 397 | |
1da177e4 LT |
398 | if (!icmpv6_xrlim_allow(sk, type, &fl)) |
399 | goto out; | |
400 | ||
401 | tmp_hdr.icmp6_type = type; | |
402 | tmp_hdr.icmp6_code = code; | |
403 | tmp_hdr.icmp6_cksum = 0; | |
404 | tmp_hdr.icmp6_pointer = htonl(info); | |
405 | ||
406 | if (!fl.oif && ipv6_addr_is_multicast(&fl.fl6_dst)) | |
407 | fl.oif = np->mcast_oif; | |
408 | ||
409 | err = ip6_dst_lookup(sk, &dst, &fl); | |
410 | if (err) | |
411 | goto out; | |
8de3351e YH |
412 | |
413 | /* | |
414 | * We won't send icmp if the destination is known | |
415 | * anycast. | |
416 | */ | |
417 | if (((struct rt6_info *)dst)->rt6i_flags & RTF_ANYCAST) { | |
418 | LIMIT_NETDEBUG(KERN_DEBUG "icmpv6_send: acast source\n"); | |
419 | goto out_dst_release; | |
420 | } | |
421 | ||
8b7817f3 HX |
422 | /* No need to clone since we're just using its address. */ |
423 | dst2 = dst; | |
424 | ||
52479b62 | 425 | err = xfrm_lookup(net, &dst, &fl, sk, 0); |
8b7817f3 HX |
426 | switch (err) { |
427 | case 0: | |
428 | if (dst != dst2) | |
429 | goto route_done; | |
430 | break; | |
431 | case -EPERM: | |
432 | dst = NULL; | |
433 | break; | |
434 | default: | |
435 | goto out; | |
436 | } | |
437 | ||
438 | if (xfrm_decode_session_reverse(skb, &fl2, AF_INET6)) | |
af268182 | 439 | goto relookup_failed; |
8b7817f3 | 440 | |
6c06a478 | 441 | if (ip6_dst_lookup(sk, &dst2, &fl2)) |
af268182 | 442 | goto relookup_failed; |
1da177e4 | 443 | |
6c06a478 | 444 | err = xfrm_lookup(net, &dst2, &fl2, sk, XFRM_LOOKUP_ICMP); |
af268182 HX |
445 | switch (err) { |
446 | case 0: | |
447 | dst_release(dst); | |
448 | dst = dst2; | |
449 | break; | |
450 | case -EPERM: | |
451 | goto out_dst_release; | |
452 | default: | |
453 | relookup_failed: | |
8b7817f3 HX |
454 | if (!dst) |
455 | goto out; | |
af268182 | 456 | break; |
8b7817f3 HX |
457 | } |
458 | ||
8b7817f3 | 459 | route_done: |
1da177e4 LT |
460 | if (ipv6_addr_is_multicast(&fl.fl6_dst)) |
461 | hlimit = np->mcast_hops; | |
462 | else | |
463 | hlimit = np->hop_limit; | |
464 | if (hlimit < 0) | |
6b75d090 | 465 | hlimit = ip6_dst_hoplimit(dst); |
1da177e4 LT |
466 | |
467 | msg.skb = skb; | |
bbe735e4 | 468 | msg.offset = skb_network_offset(skb); |
763ecff1 | 469 | msg.type = type; |
1da177e4 LT |
470 | |
471 | len = skb->len - msg.offset; | |
472 | len = min_t(unsigned int, len, IPV6_MIN_MTU - sizeof(struct ipv6hdr) -sizeof(struct icmp6hdr)); | |
473 | if (len < 0) { | |
64ce2073 | 474 | LIMIT_NETDEBUG(KERN_DEBUG "icmp: len problem\n"); |
1da177e4 LT |
475 | goto out_dst_release; |
476 | } | |
477 | ||
478 | idev = in6_dev_get(skb->dev); | |
479 | ||
480 | err = ip6_append_data(sk, icmpv6_getfrag, &msg, | |
481 | len + sizeof(struct icmp6hdr), | |
e651f03a GR |
482 | sizeof(struct icmp6hdr), hlimit, |
483 | np->tclass, NULL, &fl, (struct rt6_info*)dst, | |
1da177e4 LT |
484 | MSG_DONTWAIT); |
485 | if (err) { | |
486 | ip6_flush_pending_frames(sk); | |
487 | goto out_put; | |
488 | } | |
489 | err = icmpv6_push_pending_frames(sk, &fl, &tmp_hdr, len + sizeof(struct icmp6hdr)); | |
490 | ||
1da177e4 LT |
491 | out_put: |
492 | if (likely(idev != NULL)) | |
493 | in6_dev_put(idev); | |
494 | out_dst_release: | |
495 | dst_release(dst); | |
496 | out: | |
405666db | 497 | icmpv6_xmit_unlock(sk); |
1da177e4 LT |
498 | } |
499 | ||
7159039a YH |
500 | EXPORT_SYMBOL(icmpv6_send); |
501 | ||
1da177e4 LT |
502 | static void icmpv6_echo_reply(struct sk_buff *skb) |
503 | { | |
c346dca1 | 504 | struct net *net = dev_net(skb->dev); |
84427d53 | 505 | struct sock *sk; |
1da177e4 | 506 | struct inet6_dev *idev; |
84427d53 | 507 | struct ipv6_pinfo *np; |
1da177e4 | 508 | struct in6_addr *saddr = NULL; |
cc70ab26 | 509 | struct icmp6hdr *icmph = icmp6_hdr(skb); |
1da177e4 LT |
510 | struct icmp6hdr tmp_hdr; |
511 | struct flowi fl; | |
512 | struct icmpv6_msg msg; | |
513 | struct dst_entry *dst; | |
514 | int err = 0; | |
515 | int hlimit; | |
516 | ||
0660e03f | 517 | saddr = &ipv6_hdr(skb)->daddr; |
1da177e4 LT |
518 | |
519 | if (!ipv6_unicast_destination(skb)) | |
520 | saddr = NULL; | |
521 | ||
522 | memcpy(&tmp_hdr, icmph, sizeof(tmp_hdr)); | |
523 | tmp_hdr.icmp6_type = ICMPV6_ECHO_REPLY; | |
524 | ||
525 | memset(&fl, 0, sizeof(fl)); | |
526 | fl.proto = IPPROTO_ICMPV6; | |
0660e03f | 527 | ipv6_addr_copy(&fl.fl6_dst, &ipv6_hdr(skb)->saddr); |
1da177e4 LT |
528 | if (saddr) |
529 | ipv6_addr_copy(&fl.fl6_src, saddr); | |
530 | fl.oif = skb->dev->ifindex; | |
531 | fl.fl_icmp_type = ICMPV6_ECHO_REPLY; | |
beb8d13b | 532 | security_skb_classify_flow(skb, &fl); |
1da177e4 | 533 | |
fdc0bde9 DL |
534 | sk = icmpv6_xmit_lock(net); |
535 | if (sk == NULL) | |
405666db | 536 | return; |
fdc0bde9 | 537 | np = inet6_sk(sk); |
405666db | 538 | |
1da177e4 LT |
539 | if (!fl.oif && ipv6_addr_is_multicast(&fl.fl6_dst)) |
540 | fl.oif = np->mcast_oif; | |
541 | ||
542 | err = ip6_dst_lookup(sk, &dst, &fl); | |
543 | if (err) | |
544 | goto out; | |
52479b62 | 545 | if ((err = xfrm_lookup(net, &dst, &fl, sk, 0)) < 0) |
e104411b | 546 | goto out; |
1da177e4 LT |
547 | |
548 | if (ipv6_addr_is_multicast(&fl.fl6_dst)) | |
549 | hlimit = np->mcast_hops; | |
550 | else | |
551 | hlimit = np->hop_limit; | |
552 | if (hlimit < 0) | |
6b75d090 | 553 | hlimit = ip6_dst_hoplimit(dst); |
1da177e4 LT |
554 | |
555 | idev = in6_dev_get(skb->dev); | |
556 | ||
557 | msg.skb = skb; | |
558 | msg.offset = 0; | |
763ecff1 | 559 | msg.type = ICMPV6_ECHO_REPLY; |
1da177e4 LT |
560 | |
561 | err = ip6_append_data(sk, icmpv6_getfrag, &msg, skb->len + sizeof(struct icmp6hdr), | |
e651f03a | 562 | sizeof(struct icmp6hdr), hlimit, np->tclass, NULL, &fl, |
1da177e4 LT |
563 | (struct rt6_info*)dst, MSG_DONTWAIT); |
564 | ||
565 | if (err) { | |
566 | ip6_flush_pending_frames(sk); | |
567 | goto out_put; | |
568 | } | |
569 | err = icmpv6_push_pending_frames(sk, &fl, &tmp_hdr, skb->len + sizeof(struct icmp6hdr)); | |
570 | ||
1ab1457c | 571 | out_put: |
1da177e4 LT |
572 | if (likely(idev != NULL)) |
573 | in6_dev_put(idev); | |
1da177e4 | 574 | dst_release(dst); |
1ab1457c | 575 | out: |
405666db | 576 | icmpv6_xmit_unlock(sk); |
1da177e4 LT |
577 | } |
578 | ||
d5fdd6ba | 579 | static void icmpv6_notify(struct sk_buff *skb, u8 type, u8 code, __be32 info) |
1da177e4 | 580 | { |
41135cc8 | 581 | const struct inet6_protocol *ipprot; |
1da177e4 LT |
582 | int inner_offset; |
583 | int hash; | |
584 | u8 nexthdr; | |
585 | ||
586 | if (!pskb_may_pull(skb, sizeof(struct ipv6hdr))) | |
587 | return; | |
588 | ||
589 | nexthdr = ((struct ipv6hdr *)skb->data)->nexthdr; | |
590 | if (ipv6_ext_hdr(nexthdr)) { | |
591 | /* now skip over extension headers */ | |
0d3d077c | 592 | inner_offset = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr), &nexthdr); |
1da177e4 LT |
593 | if (inner_offset<0) |
594 | return; | |
595 | } else { | |
596 | inner_offset = sizeof(struct ipv6hdr); | |
597 | } | |
598 | ||
599 | /* Checkin header including 8 bytes of inner protocol header. */ | |
600 | if (!pskb_may_pull(skb, inner_offset+8)) | |
601 | return; | |
602 | ||
1da177e4 LT |
603 | /* BUGGG_FUTURE: we should try to parse exthdrs in this packet. |
604 | Without this we will not able f.e. to make source routed | |
605 | pmtu discovery. | |
606 | Corresponding argument (opt) to notifiers is already added. | |
607 | --ANK (980726) | |
608 | */ | |
609 | ||
610 | hash = nexthdr & (MAX_INET_PROTOS - 1); | |
611 | ||
612 | rcu_read_lock(); | |
613 | ipprot = rcu_dereference(inet6_protos[hash]); | |
614 | if (ipprot && ipprot->err_handler) | |
615 | ipprot->err_handler(skb, NULL, type, code, inner_offset, info); | |
616 | rcu_read_unlock(); | |
617 | ||
69d6da0b | 618 | raw6_icmp_error(skb, nexthdr, type, code, inner_offset, info); |
1da177e4 | 619 | } |
1ab1457c | 620 | |
1da177e4 LT |
621 | /* |
622 | * Handle icmp messages | |
623 | */ | |
624 | ||
e5bbef20 | 625 | static int icmpv6_rcv(struct sk_buff *skb) |
1da177e4 | 626 | { |
1da177e4 LT |
627 | struct net_device *dev = skb->dev; |
628 | struct inet6_dev *idev = __in6_dev_get(dev); | |
629 | struct in6_addr *saddr, *daddr; | |
630 | struct ipv6hdr *orig_hdr; | |
631 | struct icmp6hdr *hdr; | |
d5fdd6ba | 632 | u8 type; |
1da177e4 | 633 | |
aebcf82c | 634 | if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) { |
def8b4fa | 635 | struct sec_path *sp = skb_sec_path(skb); |
8b7817f3 HX |
636 | int nh; |
637 | ||
def8b4fa | 638 | if (!(sp && sp->xvec[sp->len - 1]->props.flags & |
aebcf82c HX |
639 | XFRM_STATE_ICMP)) |
640 | goto drop_no_count; | |
641 | ||
8b7817f3 HX |
642 | if (!pskb_may_pull(skb, sizeof(*hdr) + sizeof(*orig_hdr))) |
643 | goto drop_no_count; | |
644 | ||
645 | nh = skb_network_offset(skb); | |
646 | skb_set_network_header(skb, sizeof(*hdr)); | |
647 | ||
648 | if (!xfrm6_policy_check_reverse(NULL, XFRM_POLICY_IN, skb)) | |
649 | goto drop_no_count; | |
650 | ||
651 | skb_set_network_header(skb, nh); | |
652 | } | |
653 | ||
e41b5368 | 654 | ICMP6_INC_STATS_BH(dev_net(dev), idev, ICMP6_MIB_INMSGS); |
1da177e4 | 655 | |
0660e03f ACM |
656 | saddr = &ipv6_hdr(skb)->saddr; |
657 | daddr = &ipv6_hdr(skb)->daddr; | |
1da177e4 LT |
658 | |
659 | /* Perform checksum. */ | |
fb286bb2 | 660 | switch (skb->ip_summed) { |
84fa7933 | 661 | case CHECKSUM_COMPLETE: |
fb286bb2 HX |
662 | if (!csum_ipv6_magic(saddr, daddr, skb->len, IPPROTO_ICMPV6, |
663 | skb->csum)) | |
664 | break; | |
665 | /* fall through */ | |
666 | case CHECKSUM_NONE: | |
868c86bc AV |
667 | skb->csum = ~csum_unfold(csum_ipv6_magic(saddr, daddr, skb->len, |
668 | IPPROTO_ICMPV6, 0)); | |
fb286bb2 | 669 | if (__skb_checksum_complete(skb)) { |
5b095d98 | 670 | LIMIT_NETDEBUG(KERN_DEBUG "ICMPv6 checksum failed [%pI6 > %pI6]\n", |
0c6ce78a | 671 | saddr, daddr); |
1da177e4 LT |
672 | goto discard_it; |
673 | } | |
674 | } | |
675 | ||
8cf22943 HX |
676 | if (!pskb_pull(skb, sizeof(*hdr))) |
677 | goto discard_it; | |
1da177e4 | 678 | |
cc70ab26 | 679 | hdr = icmp6_hdr(skb); |
1da177e4 LT |
680 | |
681 | type = hdr->icmp6_type; | |
682 | ||
55d43808 | 683 | ICMP6MSGIN_INC_STATS_BH(dev_net(dev), idev, type); |
1da177e4 LT |
684 | |
685 | switch (type) { | |
686 | case ICMPV6_ECHO_REQUEST: | |
687 | icmpv6_echo_reply(skb); | |
688 | break; | |
689 | ||
690 | case ICMPV6_ECHO_REPLY: | |
691 | /* we couldn't care less */ | |
692 | break; | |
693 | ||
694 | case ICMPV6_PKT_TOOBIG: | |
695 | /* BUGGG_FUTURE: if packet contains rthdr, we cannot update | |
696 | standard destination cache. Seems, only "advanced" | |
697 | destination cache will allow to solve this problem | |
698 | --ANK (980726) | |
699 | */ | |
700 | if (!pskb_may_pull(skb, sizeof(struct ipv6hdr))) | |
701 | goto discard_it; | |
cc70ab26 | 702 | hdr = icmp6_hdr(skb); |
1da177e4 LT |
703 | orig_hdr = (struct ipv6hdr *) (hdr + 1); |
704 | rt6_pmtu_discovery(&orig_hdr->daddr, &orig_hdr->saddr, dev, | |
705 | ntohl(hdr->icmp6_mtu)); | |
706 | ||
707 | /* | |
708 | * Drop through to notify | |
709 | */ | |
710 | ||
711 | case ICMPV6_DEST_UNREACH: | |
712 | case ICMPV6_TIME_EXCEED: | |
713 | case ICMPV6_PARAMPROB: | |
714 | icmpv6_notify(skb, type, hdr->icmp6_code, hdr->icmp6_mtu); | |
715 | break; | |
716 | ||
717 | case NDISC_ROUTER_SOLICITATION: | |
718 | case NDISC_ROUTER_ADVERTISEMENT: | |
719 | case NDISC_NEIGHBOUR_SOLICITATION: | |
720 | case NDISC_NEIGHBOUR_ADVERTISEMENT: | |
721 | case NDISC_REDIRECT: | |
722 | ndisc_rcv(skb); | |
723 | break; | |
724 | ||
725 | case ICMPV6_MGM_QUERY: | |
726 | igmp6_event_query(skb); | |
727 | break; | |
728 | ||
729 | case ICMPV6_MGM_REPORT: | |
730 | igmp6_event_report(skb); | |
731 | break; | |
732 | ||
733 | case ICMPV6_MGM_REDUCTION: | |
734 | case ICMPV6_NI_QUERY: | |
735 | case ICMPV6_NI_REPLY: | |
736 | case ICMPV6_MLD2_REPORT: | |
737 | case ICMPV6_DHAAD_REQUEST: | |
738 | case ICMPV6_DHAAD_REPLY: | |
739 | case ICMPV6_MOBILE_PREFIX_SOL: | |
740 | case ICMPV6_MOBILE_PREFIX_ADV: | |
741 | break; | |
742 | ||
743 | default: | |
64ce2073 | 744 | LIMIT_NETDEBUG(KERN_DEBUG "icmpv6: msg of unknown type\n"); |
1da177e4 LT |
745 | |
746 | /* informational */ | |
747 | if (type & ICMPV6_INFOMSG_MASK) | |
748 | break; | |
749 | ||
1ab1457c YH |
750 | /* |
751 | * error of unknown type. | |
752 | * must pass to upper level | |
1da177e4 LT |
753 | */ |
754 | ||
755 | icmpv6_notify(skb, type, hdr->icmp6_code, hdr->icmp6_mtu); | |
3ff50b79 SH |
756 | } |
757 | ||
1da177e4 LT |
758 | kfree_skb(skb); |
759 | return 0; | |
760 | ||
761 | discard_it: | |
e41b5368 | 762 | ICMP6_INC_STATS_BH(dev_net(dev), idev, ICMP6_MIB_INERRORS); |
8b7817f3 | 763 | drop_no_count: |
1da177e4 LT |
764 | kfree_skb(skb); |
765 | return 0; | |
766 | } | |
767 | ||
95e41e93 YH |
768 | void icmpv6_flow_init(struct sock *sk, struct flowi *fl, |
769 | u8 type, | |
770 | const struct in6_addr *saddr, | |
771 | const struct in6_addr *daddr, | |
772 | int oif) | |
773 | { | |
774 | memset(fl, 0, sizeof(*fl)); | |
775 | ipv6_addr_copy(&fl->fl6_src, saddr); | |
776 | ipv6_addr_copy(&fl->fl6_dst, daddr); | |
777 | fl->proto = IPPROTO_ICMPV6; | |
778 | fl->fl_icmp_type = type; | |
779 | fl->fl_icmp_code = 0; | |
780 | fl->oif = oif; | |
781 | security_sk_classify_flow(sk, fl); | |
782 | } | |
783 | ||
640c41c7 | 784 | /* |
b7e729c4 | 785 | * Special lock-class for __icmpv6_sk: |
640c41c7 IM |
786 | */ |
787 | static struct lock_class_key icmpv6_socket_sk_dst_lock_key; | |
788 | ||
98c6d1b2 | 789 | static int __net_init icmpv6_sk_init(struct net *net) |
1da177e4 LT |
790 | { |
791 | struct sock *sk; | |
792 | int err, i, j; | |
793 | ||
98c6d1b2 DL |
794 | net->ipv6.icmp_sk = |
795 | kzalloc(nr_cpu_ids * sizeof(struct sock *), GFP_KERNEL); | |
796 | if (net->ipv6.icmp_sk == NULL) | |
79c91159 DL |
797 | return -ENOMEM; |
798 | ||
6f912042 | 799 | for_each_possible_cpu(i) { |
1ed8516f DL |
800 | err = inet_ctl_sock_create(&sk, PF_INET6, |
801 | SOCK_RAW, IPPROTO_ICMPV6, net); | |
1da177e4 LT |
802 | if (err < 0) { |
803 | printk(KERN_ERR | |
804 | "Failed to initialize the ICMP6 control socket " | |
805 | "(err %d).\n", | |
806 | err); | |
807 | goto fail; | |
808 | } | |
809 | ||
1ed8516f | 810 | net->ipv6.icmp_sk[i] = sk; |
5c8cafd6 | 811 | |
640c41c7 IM |
812 | /* |
813 | * Split off their lock-class, because sk->sk_dst_lock | |
814 | * gets used from softirqs, which is safe for | |
b7e729c4 | 815 | * __icmpv6_sk (because those never get directly used |
640c41c7 IM |
816 | * via userspace syscalls), but unsafe for normal sockets. |
817 | */ | |
818 | lockdep_set_class(&sk->sk_dst_lock, | |
819 | &icmpv6_socket_sk_dst_lock_key); | |
1da177e4 LT |
820 | |
821 | /* Enough space for 2 64K ICMP packets, including | |
822 | * sk_buff struct overhead. | |
823 | */ | |
824 | sk->sk_sndbuf = | |
825 | (2 * ((64 * 1024) + sizeof(struct sk_buff))); | |
1da177e4 | 826 | } |
1da177e4 LT |
827 | return 0; |
828 | ||
829 | fail: | |
5c8cafd6 | 830 | for (j = 0; j < i; j++) |
1ed8516f | 831 | inet_ctl_sock_destroy(net->ipv6.icmp_sk[j]); |
98c6d1b2 | 832 | kfree(net->ipv6.icmp_sk); |
1da177e4 LT |
833 | return err; |
834 | } | |
835 | ||
98c6d1b2 | 836 | static void __net_exit icmpv6_sk_exit(struct net *net) |
1da177e4 LT |
837 | { |
838 | int i; | |
839 | ||
6f912042 | 840 | for_each_possible_cpu(i) { |
1ed8516f | 841 | inet_ctl_sock_destroy(net->ipv6.icmp_sk[i]); |
1da177e4 | 842 | } |
98c6d1b2 DL |
843 | kfree(net->ipv6.icmp_sk); |
844 | } | |
845 | ||
8ed7edce | 846 | static struct pernet_operations icmpv6_sk_ops = { |
98c6d1b2 DL |
847 | .init = icmpv6_sk_init, |
848 | .exit = icmpv6_sk_exit, | |
849 | }; | |
850 | ||
851 | int __init icmpv6_init(void) | |
852 | { | |
853 | int err; | |
854 | ||
855 | err = register_pernet_subsys(&icmpv6_sk_ops); | |
856 | if (err < 0) | |
857 | return err; | |
858 | ||
859 | err = -EAGAIN; | |
860 | if (inet6_add_protocol(&icmpv6_protocol, IPPROTO_ICMPV6) < 0) | |
861 | goto fail; | |
862 | return 0; | |
863 | ||
864 | fail: | |
865 | printk(KERN_ERR "Failed to register ICMP6 protocol\n"); | |
866 | unregister_pernet_subsys(&icmpv6_sk_ops); | |
867 | return err; | |
868 | } | |
869 | ||
8ed7edce | 870 | void icmpv6_cleanup(void) |
98c6d1b2 DL |
871 | { |
872 | unregister_pernet_subsys(&icmpv6_sk_ops); | |
1da177e4 LT |
873 | inet6_del_protocol(&icmpv6_protocol, IPPROTO_ICMPV6); |
874 | } | |
875 | ||
98c6d1b2 | 876 | |
9b5b5cff | 877 | static const struct icmp6_err { |
1da177e4 LT |
878 | int err; |
879 | int fatal; | |
880 | } tab_unreach[] = { | |
881 | { /* NOROUTE */ | |
882 | .err = ENETUNREACH, | |
883 | .fatal = 0, | |
884 | }, | |
885 | { /* ADM_PROHIBITED */ | |
886 | .err = EACCES, | |
887 | .fatal = 1, | |
888 | }, | |
889 | { /* Was NOT_NEIGHBOUR, now reserved */ | |
890 | .err = EHOSTUNREACH, | |
891 | .fatal = 0, | |
892 | }, | |
893 | { /* ADDR_UNREACH */ | |
894 | .err = EHOSTUNREACH, | |
895 | .fatal = 0, | |
896 | }, | |
897 | { /* PORT_UNREACH */ | |
898 | .err = ECONNREFUSED, | |
899 | .fatal = 1, | |
900 | }, | |
901 | }; | |
902 | ||
d5fdd6ba | 903 | int icmpv6_err_convert(u8 type, u8 code, int *err) |
1da177e4 LT |
904 | { |
905 | int fatal = 0; | |
906 | ||
907 | *err = EPROTO; | |
908 | ||
909 | switch (type) { | |
910 | case ICMPV6_DEST_UNREACH: | |
911 | fatal = 1; | |
912 | if (code <= ICMPV6_PORT_UNREACH) { | |
913 | *err = tab_unreach[code].err; | |
914 | fatal = tab_unreach[code].fatal; | |
915 | } | |
916 | break; | |
917 | ||
918 | case ICMPV6_PKT_TOOBIG: | |
919 | *err = EMSGSIZE; | |
920 | break; | |
1ab1457c | 921 | |
1da177e4 LT |
922 | case ICMPV6_PARAMPROB: |
923 | *err = EPROTO; | |
924 | fatal = 1; | |
925 | break; | |
926 | ||
927 | case ICMPV6_TIME_EXCEED: | |
928 | *err = EHOSTUNREACH; | |
929 | break; | |
3ff50b79 | 930 | } |
1da177e4 LT |
931 | |
932 | return fatal; | |
933 | } | |
934 | ||
7159039a YH |
935 | EXPORT_SYMBOL(icmpv6_err_convert); |
936 | ||
1da177e4 | 937 | #ifdef CONFIG_SYSCTL |
760f2d01 | 938 | ctl_table ipv6_icmp_table_template[] = { |
1da177e4 | 939 | { |
1da177e4 | 940 | .procname = "ratelimit", |
41a76906 | 941 | .data = &init_net.ipv6.sysctl.icmpv6_time, |
1da177e4 LT |
942 | .maxlen = sizeof(int), |
943 | .mode = 0644, | |
6d9f239a | 944 | .proc_handler = proc_dointvec_ms_jiffies, |
1da177e4 | 945 | }, |
f8572d8f | 946 | { }, |
1da177e4 | 947 | }; |
760f2d01 | 948 | |
2c8c1e72 | 949 | struct ctl_table * __net_init ipv6_icmp_sysctl_init(struct net *net) |
760f2d01 DL |
950 | { |
951 | struct ctl_table *table; | |
952 | ||
953 | table = kmemdup(ipv6_icmp_table_template, | |
954 | sizeof(ipv6_icmp_table_template), | |
955 | GFP_KERNEL); | |
5ee09105 YH |
956 | |
957 | if (table) | |
958 | table[0].data = &net->ipv6.sysctl.icmpv6_time; | |
959 | ||
760f2d01 DL |
960 | return table; |
961 | } | |
1da177e4 LT |
962 | #endif |
963 |