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Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * NET3: Implementation of the ICMP protocol layer. | |
3 | * | |
4 | * Alan Cox, <alan@redhat.com> | |
5 | * | |
6 | * Version: $Id: icmp.c,v 1.85 2002/02/01 22:01:03 davem Exp $ | |
7 | * | |
8 | * This program is free software; you can redistribute it and/or | |
9 | * modify it under the terms of the GNU General Public License | |
10 | * as published by the Free Software Foundation; either version | |
11 | * 2 of the License, or (at your option) any later version. | |
12 | * | |
13 | * Some of the function names and the icmp unreach table for this | |
14 | * module were derived from [icmp.c 1.0.11 06/02/93] by | |
15 | * Ross Biro, Fred N. van Kempen, Mark Evans, Alan Cox, Gerhard Koerting. | |
16 | * Other than that this module is a complete rewrite. | |
17 | * | |
18 | * Fixes: | |
19 | * Clemens Fruhwirth : introduce global icmp rate limiting | |
20 | * with icmp type masking ability instead | |
21 | * of broken per type icmp timeouts. | |
22 | * Mike Shaver : RFC1122 checks. | |
23 | * Alan Cox : Multicast ping reply as self. | |
24 | * Alan Cox : Fix atomicity lockup in ip_build_xmit | |
25 | * call. | |
26 | * Alan Cox : Added 216,128 byte paths to the MTU | |
27 | * code. | |
28 | * Martin Mares : RFC1812 checks. | |
29 | * Martin Mares : Can be configured to follow redirects | |
30 | * if acting as a router _without_ a | |
31 | * routing protocol (RFC 1812). | |
32 | * Martin Mares : Echo requests may be configured to | |
33 | * be ignored (RFC 1812). | |
34 | * Martin Mares : Limitation of ICMP error message | |
35 | * transmit rate (RFC 1812). | |
36 | * Martin Mares : TOS and Precedence set correctly | |
37 | * (RFC 1812). | |
38 | * Martin Mares : Now copying as much data from the | |
39 | * original packet as we can without | |
40 | * exceeding 576 bytes (RFC 1812). | |
41 | * Willy Konynenberg : Transparent proxying support. | |
42 | * Keith Owens : RFC1191 correction for 4.2BSD based | |
43 | * path MTU bug. | |
44 | * Thomas Quinot : ICMP Dest Unreach codes up to 15 are | |
45 | * valid (RFC 1812). | |
46 | * Andi Kleen : Check all packet lengths properly | |
47 | * and moved all kfree_skb() up to | |
48 | * icmp_rcv. | |
49 | * Andi Kleen : Move the rate limit bookkeeping | |
50 | * into the dest entry and use a token | |
51 | * bucket filter (thanks to ANK). Make | |
52 | * the rates sysctl configurable. | |
53 | * Yu Tianli : Fixed two ugly bugs in icmp_send | |
54 | * - IP option length was accounted wrongly | |
55 | * - ICMP header length was not accounted | |
56 | * at all. | |
57 | * Tristan Greaves : Added sysctl option to ignore bogus | |
58 | * broadcast responses from broken routers. | |
59 | * | |
60 | * To Fix: | |
61 | * | |
62 | * - Should use skb_pull() instead of all the manual checking. | |
63 | * This would also greatly simply some upper layer error handlers. --AK | |
64 | * | |
65 | */ | |
66 | ||
1da177e4 LT |
67 | #include <linux/module.h> |
68 | #include <linux/types.h> | |
69 | #include <linux/jiffies.h> | |
70 | #include <linux/kernel.h> | |
71 | #include <linux/fcntl.h> | |
72 | #include <linux/socket.h> | |
73 | #include <linux/in.h> | |
74 | #include <linux/inet.h> | |
14c85021 | 75 | #include <linux/inetdevice.h> |
1da177e4 LT |
76 | #include <linux/netdevice.h> |
77 | #include <linux/string.h> | |
78 | #include <linux/netfilter_ipv4.h> | |
79 | #include <net/snmp.h> | |
80 | #include <net/ip.h> | |
81 | #include <net/route.h> | |
82 | #include <net/protocol.h> | |
83 | #include <net/icmp.h> | |
84 | #include <net/tcp.h> | |
85 | #include <net/udp.h> | |
86 | #include <net/raw.h> | |
87 | #include <linux/skbuff.h> | |
88 | #include <net/sock.h> | |
89 | #include <linux/errno.h> | |
90 | #include <linux/timer.h> | |
91 | #include <linux/init.h> | |
92 | #include <asm/system.h> | |
93 | #include <asm/uaccess.h> | |
94 | #include <net/checksum.h> | |
8b7817f3 | 95 | #include <net/xfrm.h> |
1da177e4 LT |
96 | |
97 | /* | |
98 | * Build xmit assembly blocks | |
99 | */ | |
100 | ||
101 | struct icmp_bxm { | |
102 | struct sk_buff *skb; | |
103 | int offset; | |
104 | int data_len; | |
105 | ||
106 | struct { | |
107 | struct icmphdr icmph; | |
b03d73e3 | 108 | __be32 times[3]; |
1da177e4 LT |
109 | } data; |
110 | int head_len; | |
111 | struct ip_options replyopts; | |
112 | unsigned char optbuf[40]; | |
113 | }; | |
114 | ||
115 | /* | |
116 | * Statistics | |
117 | */ | |
ba89966c | 118 | DEFINE_SNMP_STAT(struct icmp_mib, icmp_statistics) __read_mostly; |
96793b48 | 119 | DEFINE_SNMP_STAT(struct icmpmsg_mib, icmpmsg_statistics) __read_mostly; |
1da177e4 LT |
120 | |
121 | /* An array of errno for error messages from dest unreach. */ | |
122 | /* RFC 1122: 3.2.2.1 States that NET_UNREACH, HOST_UNREACH and SR_FAILED MUST be considered 'transient errs'. */ | |
123 | ||
124 | struct icmp_err icmp_err_convert[] = { | |
125 | { | |
126 | .errno = ENETUNREACH, /* ICMP_NET_UNREACH */ | |
127 | .fatal = 0, | |
128 | }, | |
129 | { | |
130 | .errno = EHOSTUNREACH, /* ICMP_HOST_UNREACH */ | |
131 | .fatal = 0, | |
132 | }, | |
133 | { | |
134 | .errno = ENOPROTOOPT /* ICMP_PROT_UNREACH */, | |
135 | .fatal = 1, | |
136 | }, | |
137 | { | |
138 | .errno = ECONNREFUSED, /* ICMP_PORT_UNREACH */ | |
139 | .fatal = 1, | |
140 | }, | |
141 | { | |
142 | .errno = EMSGSIZE, /* ICMP_FRAG_NEEDED */ | |
143 | .fatal = 0, | |
144 | }, | |
145 | { | |
146 | .errno = EOPNOTSUPP, /* ICMP_SR_FAILED */ | |
147 | .fatal = 0, | |
148 | }, | |
149 | { | |
150 | .errno = ENETUNREACH, /* ICMP_NET_UNKNOWN */ | |
151 | .fatal = 1, | |
152 | }, | |
153 | { | |
154 | .errno = EHOSTDOWN, /* ICMP_HOST_UNKNOWN */ | |
155 | .fatal = 1, | |
156 | }, | |
157 | { | |
158 | .errno = ENONET, /* ICMP_HOST_ISOLATED */ | |
159 | .fatal = 1, | |
160 | }, | |
161 | { | |
162 | .errno = ENETUNREACH, /* ICMP_NET_ANO */ | |
163 | .fatal = 1, | |
164 | }, | |
165 | { | |
166 | .errno = EHOSTUNREACH, /* ICMP_HOST_ANO */ | |
167 | .fatal = 1, | |
168 | }, | |
169 | { | |
170 | .errno = ENETUNREACH, /* ICMP_NET_UNR_TOS */ | |
171 | .fatal = 0, | |
172 | }, | |
173 | { | |
174 | .errno = EHOSTUNREACH, /* ICMP_HOST_UNR_TOS */ | |
175 | .fatal = 0, | |
176 | }, | |
177 | { | |
178 | .errno = EHOSTUNREACH, /* ICMP_PKT_FILTERED */ | |
179 | .fatal = 1, | |
180 | }, | |
181 | { | |
182 | .errno = EHOSTUNREACH, /* ICMP_PREC_VIOLATION */ | |
183 | .fatal = 1, | |
184 | }, | |
185 | { | |
186 | .errno = EHOSTUNREACH, /* ICMP_PREC_CUTOFF */ | |
187 | .fatal = 1, | |
188 | }, | |
189 | }; | |
190 | ||
191 | /* Control parameters for ECHO replies. */ | |
ab32ea5d BH |
192 | int sysctl_icmp_echo_ignore_all __read_mostly; |
193 | int sysctl_icmp_echo_ignore_broadcasts __read_mostly = 1; | |
1da177e4 LT |
194 | |
195 | /* Control parameter - ignore bogus broadcast responses? */ | |
ab32ea5d | 196 | int sysctl_icmp_ignore_bogus_error_responses __read_mostly = 1; |
1da177e4 LT |
197 | |
198 | /* | |
199 | * Configurable global rate limit. | |
200 | * | |
201 | * ratelimit defines tokens/packet consumed for dst->rate_token bucket | |
202 | * ratemask defines which icmp types are ratelimited by setting | |
203 | * it's bit position. | |
204 | * | |
205 | * default: | |
206 | * dest unreachable (3), source quench (4), | |
207 | * time exceeded (11), parameter problem (12) | |
208 | */ | |
209 | ||
ab32ea5d BH |
210 | int sysctl_icmp_ratelimit __read_mostly = 1 * HZ; |
211 | int sysctl_icmp_ratemask __read_mostly = 0x1818; | |
212 | int sysctl_icmp_errors_use_inbound_ifaddr __read_mostly; | |
1da177e4 LT |
213 | |
214 | /* | |
215 | * ICMP control array. This specifies what to do with each ICMP. | |
216 | */ | |
217 | ||
218 | struct icmp_control { | |
1da177e4 LT |
219 | void (*handler)(struct sk_buff *skb); |
220 | short error; /* This ICMP is classed as an error message */ | |
221 | }; | |
222 | ||
9b5b5cff | 223 | static const struct icmp_control icmp_pointers[NR_ICMP_TYPES+1]; |
1da177e4 LT |
224 | |
225 | /* | |
226 | * The ICMP socket(s). This is the most convenient way to flow control | |
227 | * our ICMP output as well as maintain a clean interface throughout | |
228 | * all layers. All Socketless IP sends will soon be gone. | |
229 | * | |
230 | * On SMP we have one ICMP socket per-cpu. | |
231 | */ | |
4a6ad7a1 DL |
232 | static struct sock *icmp_sk(struct net *net) |
233 | { | |
234 | return net->ipv4.icmp_sk[smp_processor_id()]; | |
235 | } | |
1da177e4 | 236 | |
405666db | 237 | static inline int icmp_xmit_lock(struct sock *sk) |
1da177e4 LT |
238 | { |
239 | local_bh_disable(); | |
240 | ||
405666db | 241 | if (unlikely(!spin_trylock(&sk->sk_lock.slock))) { |
1da177e4 LT |
242 | /* This can happen if the output path signals a |
243 | * dst_link_failure() for an outgoing ICMP packet. | |
244 | */ | |
245 | local_bh_enable(); | |
246 | return 1; | |
247 | } | |
248 | return 0; | |
249 | } | |
250 | ||
405666db | 251 | static inline void icmp_xmit_unlock(struct sock *sk) |
1da177e4 | 252 | { |
405666db | 253 | spin_unlock_bh(&sk->sk_lock.slock); |
1da177e4 LT |
254 | } |
255 | ||
256 | /* | |
257 | * Send an ICMP frame. | |
258 | */ | |
259 | ||
260 | /* | |
261 | * Check transmit rate limitation for given message. | |
262 | * The rate information is held in the destination cache now. | |
263 | * This function is generic and could be used for other purposes | |
264 | * too. It uses a Token bucket filter as suggested by Alexey Kuznetsov. | |
265 | * | |
266 | * Note that the same dst_entry fields are modified by functions in | |
267 | * route.c too, but these work for packet destinations while xrlim_allow | |
268 | * works for icmp destinations. This means the rate limiting information | |
269 | * for one "ip object" is shared - and these ICMPs are twice limited: | |
270 | * by source and by destination. | |
271 | * | |
272 | * RFC 1812: 4.3.2.8 SHOULD be able to limit error message rate | |
273 | * SHOULD allow setting of rate limits | |
274 | * | |
275 | * Shared between ICMPv4 and ICMPv6. | |
276 | */ | |
277 | #define XRLIM_BURST_FACTOR 6 | |
278 | int xrlim_allow(struct dst_entry *dst, int timeout) | |
279 | { | |
69a73829 | 280 | unsigned long now, token = dst->rate_tokens; |
1da177e4 LT |
281 | int rc = 0; |
282 | ||
283 | now = jiffies; | |
69a73829 | 284 | token += now - dst->rate_last; |
1da177e4 | 285 | dst->rate_last = now; |
69a73829 ED |
286 | if (token > XRLIM_BURST_FACTOR * timeout) |
287 | token = XRLIM_BURST_FACTOR * timeout; | |
288 | if (token >= timeout) { | |
289 | token -= timeout; | |
1da177e4 LT |
290 | rc = 1; |
291 | } | |
69a73829 | 292 | dst->rate_tokens = token; |
1da177e4 LT |
293 | return rc; |
294 | } | |
295 | ||
296 | static inline int icmpv4_xrlim_allow(struct rtable *rt, int type, int code) | |
297 | { | |
298 | struct dst_entry *dst = &rt->u.dst; | |
299 | int rc = 1; | |
300 | ||
301 | if (type > NR_ICMP_TYPES) | |
302 | goto out; | |
303 | ||
304 | /* Don't limit PMTU discovery. */ | |
305 | if (type == ICMP_DEST_UNREACH && code == ICMP_FRAG_NEEDED) | |
306 | goto out; | |
307 | ||
308 | /* No rate limit on loopback */ | |
309 | if (dst->dev && (dst->dev->flags&IFF_LOOPBACK)) | |
e905a9ed | 310 | goto out; |
1da177e4 LT |
311 | |
312 | /* Limit if icmp type is enabled in ratemask. */ | |
313 | if ((1 << type) & sysctl_icmp_ratemask) | |
314 | rc = xrlim_allow(dst, sysctl_icmp_ratelimit); | |
315 | out: | |
316 | return rc; | |
317 | } | |
318 | ||
319 | /* | |
320 | * Maintain the counters used in the SNMP statistics for outgoing ICMP | |
321 | */ | |
96793b48 | 322 | void icmp_out_count(unsigned char type) |
1da177e4 | 323 | { |
96793b48 DS |
324 | ICMPMSGOUT_INC_STATS(type); |
325 | ICMP_INC_STATS(ICMP_MIB_OUTMSGS); | |
1da177e4 LT |
326 | } |
327 | ||
328 | /* | |
329 | * Checksum each fragment, and on the first include the headers and final | |
330 | * checksum. | |
331 | */ | |
332 | static int icmp_glue_bits(void *from, char *to, int offset, int len, int odd, | |
333 | struct sk_buff *skb) | |
334 | { | |
335 | struct icmp_bxm *icmp_param = (struct icmp_bxm *)from; | |
5f92a738 | 336 | __wsum csum; |
1da177e4 LT |
337 | |
338 | csum = skb_copy_and_csum_bits(icmp_param->skb, | |
339 | icmp_param->offset + offset, | |
340 | to, len, 0); | |
341 | ||
342 | skb->csum = csum_block_add(skb->csum, csum, odd); | |
343 | if (icmp_pointers[icmp_param->data.icmph.type].error) | |
344 | nf_ct_attach(skb, icmp_param->skb); | |
345 | return 0; | |
346 | } | |
347 | ||
348 | static void icmp_push_reply(struct icmp_bxm *icmp_param, | |
349 | struct ipcm_cookie *ipc, struct rtable *rt) | |
350 | { | |
1e3cf683 | 351 | struct sock *sk; |
1da177e4 LT |
352 | struct sk_buff *skb; |
353 | ||
4a6ad7a1 | 354 | sk = icmp_sk(rt->u.dst.dev->nd_net); |
1e3cf683 | 355 | if (ip_append_data(sk, icmp_glue_bits, icmp_param, |
e905a9ed YH |
356 | icmp_param->data_len+icmp_param->head_len, |
357 | icmp_param->head_len, | |
358 | ipc, rt, MSG_DONTWAIT) < 0) | |
1e3cf683 DL |
359 | ip_flush_pending_frames(sk); |
360 | else if ((skb = skb_peek(&sk->sk_write_queue)) != NULL) { | |
88c7664f | 361 | struct icmphdr *icmph = icmp_hdr(skb); |
d3bc23e7 | 362 | __wsum csum = 0; |
1da177e4 LT |
363 | struct sk_buff *skb1; |
364 | ||
1e3cf683 | 365 | skb_queue_walk(&sk->sk_write_queue, skb1) { |
1da177e4 LT |
366 | csum = csum_add(csum, skb1->csum); |
367 | } | |
368 | csum = csum_partial_copy_nocheck((void *)&icmp_param->data, | |
369 | (char *)icmph, | |
370 | icmp_param->head_len, csum); | |
371 | icmph->checksum = csum_fold(csum); | |
372 | skb->ip_summed = CHECKSUM_NONE; | |
1e3cf683 | 373 | ip_push_pending_frames(sk); |
1da177e4 LT |
374 | } |
375 | } | |
376 | ||
377 | /* | |
378 | * Driving logic for building and sending ICMP messages. | |
379 | */ | |
380 | ||
381 | static void icmp_reply(struct icmp_bxm *icmp_param, struct sk_buff *skb) | |
382 | { | |
1da177e4 LT |
383 | struct ipcm_cookie ipc; |
384 | struct rtable *rt = (struct rtable *)skb->dst; | |
4a6ad7a1 DL |
385 | struct net *net = rt->u.dst.dev->nd_net; |
386 | struct sock *sk = icmp_sk(net); | |
387 | struct inet_sock *inet = inet_sk(sk); | |
3ca3c68e | 388 | __be32 daddr; |
1da177e4 LT |
389 | |
390 | if (ip_options_echo(&icmp_param->replyopts, skb)) | |
f00c401b | 391 | return; |
1da177e4 | 392 | |
405666db | 393 | if (icmp_xmit_lock(sk)) |
1da177e4 LT |
394 | return; |
395 | ||
396 | icmp_param->data.icmph.checksum = 0; | |
1da177e4 | 397 | |
eddc9ec5 | 398 | inet->tos = ip_hdr(skb)->tos; |
1da177e4 LT |
399 | daddr = ipc.addr = rt->rt_src; |
400 | ipc.opt = NULL; | |
401 | if (icmp_param->replyopts.optlen) { | |
402 | ipc.opt = &icmp_param->replyopts; | |
403 | if (ipc.opt->srr) | |
404 | daddr = icmp_param->replyopts.faddr; | |
405 | } | |
406 | { | |
407 | struct flowi fl = { .nl_u = { .ip4_u = | |
408 | { .daddr = daddr, | |
409 | .saddr = rt->rt_spec_dst, | |
eddc9ec5 | 410 | .tos = RT_TOS(ip_hdr(skb)->tos) } }, |
1da177e4 | 411 | .proto = IPPROTO_ICMP }; |
beb8d13b | 412 | security_skb_classify_flow(skb, &fl); |
4a6ad7a1 | 413 | if (ip_route_output_key(net, &rt, &fl)) |
1da177e4 LT |
414 | goto out_unlock; |
415 | } | |
416 | if (icmpv4_xrlim_allow(rt, icmp_param->data.icmph.type, | |
417 | icmp_param->data.icmph.code)) | |
418 | icmp_push_reply(icmp_param, &ipc, rt); | |
419 | ip_rt_put(rt); | |
420 | out_unlock: | |
405666db | 421 | icmp_xmit_unlock(sk); |
1da177e4 LT |
422 | } |
423 | ||
424 | ||
425 | /* | |
426 | * Send an ICMP message in response to a situation | |
427 | * | |
428 | * RFC 1122: 3.2.2 MUST send at least the IP header and 8 bytes of header. | |
429 | * MAY send more (we do). | |
430 | * MUST NOT change this header information. | |
431 | * MUST NOT reply to a multicast/broadcast IP address. | |
432 | * MUST NOT reply to a multicast/broadcast MAC address. | |
433 | * MUST reply to only the first fragment. | |
434 | */ | |
435 | ||
e4883014 | 436 | void icmp_send(struct sk_buff *skb_in, int type, int code, __be32 info) |
1da177e4 LT |
437 | { |
438 | struct iphdr *iph; | |
439 | int room; | |
440 | struct icmp_bxm icmp_param; | |
441 | struct rtable *rt = (struct rtable *)skb_in->dst; | |
442 | struct ipcm_cookie ipc; | |
a61ced5d | 443 | __be32 saddr; |
1da177e4 | 444 | u8 tos; |
dde1bc0e | 445 | struct net *net; |
4a6ad7a1 | 446 | struct sock *sk; |
1da177e4 LT |
447 | |
448 | if (!rt) | |
449 | goto out; | |
dde1bc0e | 450 | net = rt->u.dst.dev->nd_net; |
4a6ad7a1 | 451 | sk = icmp_sk(net); |
1da177e4 LT |
452 | |
453 | /* | |
454 | * Find the original header. It is expected to be valid, of course. | |
455 | * Check this, icmp_send is called from the most obscure devices | |
456 | * sometimes. | |
457 | */ | |
eddc9ec5 | 458 | iph = ip_hdr(skb_in); |
1da177e4 | 459 | |
27a884dc ACM |
460 | if ((u8 *)iph < skb_in->head || |
461 | (skb_in->network_header + sizeof(*iph)) > skb_in->tail) | |
1da177e4 LT |
462 | goto out; |
463 | ||
464 | /* | |
465 | * No replies to physical multicast/broadcast | |
466 | */ | |
467 | if (skb_in->pkt_type != PACKET_HOST) | |
468 | goto out; | |
469 | ||
470 | /* | |
471 | * Now check at the protocol level | |
472 | */ | |
473 | if (rt->rt_flags & (RTCF_BROADCAST | RTCF_MULTICAST)) | |
474 | goto out; | |
475 | ||
476 | /* | |
477 | * Only reply to fragment 0. We byte re-order the constant | |
478 | * mask for efficiency. | |
479 | */ | |
480 | if (iph->frag_off & htons(IP_OFFSET)) | |
481 | goto out; | |
482 | ||
483 | /* | |
484 | * If we send an ICMP error to an ICMP error a mess would result.. | |
485 | */ | |
486 | if (icmp_pointers[type].error) { | |
487 | /* | |
488 | * We are an error, check if we are replying to an | |
489 | * ICMP error | |
490 | */ | |
491 | if (iph->protocol == IPPROTO_ICMP) { | |
492 | u8 _inner_type, *itp; | |
493 | ||
494 | itp = skb_header_pointer(skb_in, | |
d56f90a7 | 495 | skb_network_header(skb_in) + |
1da177e4 LT |
496 | (iph->ihl << 2) + |
497 | offsetof(struct icmphdr, | |
498 | type) - | |
499 | skb_in->data, | |
500 | sizeof(_inner_type), | |
501 | &_inner_type); | |
502 | if (itp == NULL) | |
503 | goto out; | |
504 | ||
505 | /* | |
506 | * Assume any unknown ICMP type is an error. This | |
507 | * isn't specified by the RFC, but think about it.. | |
508 | */ | |
509 | if (*itp > NR_ICMP_TYPES || | |
510 | icmp_pointers[*itp].error) | |
511 | goto out; | |
512 | } | |
513 | } | |
514 | ||
405666db | 515 | if (icmp_xmit_lock(sk)) |
1da177e4 LT |
516 | return; |
517 | ||
518 | /* | |
519 | * Construct source address and options. | |
520 | */ | |
521 | ||
522 | saddr = iph->daddr; | |
1c2fb7f9 | 523 | if (!(rt->rt_flags & RTCF_LOCAL)) { |
6e1d9103 PM |
524 | struct net_device *dev = NULL; |
525 | ||
526 | if (rt->fl.iif && sysctl_icmp_errors_use_inbound_ifaddr) | |
dde1bc0e | 527 | dev = dev_get_by_index(net, rt->fl.iif); |
6e1d9103 PM |
528 | |
529 | if (dev) { | |
530 | saddr = inet_select_addr(dev, 0, RT_SCOPE_LINK); | |
531 | dev_put(dev); | |
532 | } else | |
1c2fb7f9 S |
533 | saddr = 0; |
534 | } | |
1da177e4 LT |
535 | |
536 | tos = icmp_pointers[type].error ? ((iph->tos & IPTOS_TOS_MASK) | | |
537 | IPTOS_PREC_INTERNETCONTROL) : | |
538 | iph->tos; | |
539 | ||
540 | if (ip_options_echo(&icmp_param.replyopts, skb_in)) | |
fa60cf7f | 541 | goto out_unlock; |
1da177e4 LT |
542 | |
543 | ||
544 | /* | |
545 | * Prepare data for ICMP header. | |
546 | */ | |
547 | ||
548 | icmp_param.data.icmph.type = type; | |
549 | icmp_param.data.icmph.code = code; | |
550 | icmp_param.data.icmph.un.gateway = info; | |
551 | icmp_param.data.icmph.checksum = 0; | |
552 | icmp_param.skb = skb_in; | |
d56f90a7 | 553 | icmp_param.offset = skb_network_offset(skb_in); |
405666db | 554 | inet_sk(sk)->tos = tos; |
1da177e4 LT |
555 | ipc.addr = iph->saddr; |
556 | ipc.opt = &icmp_param.replyopts; | |
557 | ||
558 | { | |
559 | struct flowi fl = { | |
560 | .nl_u = { | |
561 | .ip4_u = { | |
562 | .daddr = icmp_param.replyopts.srr ? | |
563 | icmp_param.replyopts.faddr : | |
564 | iph->saddr, | |
565 | .saddr = saddr, | |
566 | .tos = RT_TOS(tos) | |
567 | } | |
568 | }, | |
569 | .proto = IPPROTO_ICMP, | |
570 | .uli_u = { | |
571 | .icmpt = { | |
572 | .type = type, | |
573 | .code = code | |
574 | } | |
575 | } | |
576 | }; | |
8b7817f3 HX |
577 | int err; |
578 | struct rtable *rt2; | |
579 | ||
beb8d13b | 580 | security_skb_classify_flow(skb_in, &fl); |
dde1bc0e | 581 | if (__ip_route_output_key(net, &rt, &fl)) |
8b7817f3 HX |
582 | goto out_unlock; |
583 | ||
584 | /* No need to clone since we're just using its address. */ | |
585 | rt2 = rt; | |
586 | ||
587 | err = xfrm_lookup((struct dst_entry **)&rt, &fl, NULL, 0); | |
588 | switch (err) { | |
589 | case 0: | |
590 | if (rt != rt2) | |
591 | goto route_done; | |
592 | break; | |
593 | case -EPERM: | |
594 | rt = NULL; | |
595 | break; | |
596 | default: | |
597 | goto out_unlock; | |
598 | } | |
599 | ||
600 | if (xfrm_decode_session_reverse(skb_in, &fl, AF_INET)) | |
601 | goto out_unlock; | |
602 | ||
dde1bc0e DL |
603 | if (inet_addr_type(net, fl.fl4_src) == RTN_LOCAL) |
604 | err = __ip_route_output_key(net, &rt2, &fl); | |
8b7817f3 HX |
605 | else { |
606 | struct flowi fl2 = {}; | |
607 | struct dst_entry *odst; | |
608 | ||
609 | fl2.fl4_dst = fl.fl4_src; | |
dde1bc0e | 610 | if (ip_route_output_key(net, &rt2, &fl2)) |
8b7817f3 HX |
611 | goto out_unlock; |
612 | ||
613 | /* Ugh! */ | |
614 | odst = skb_in->dst; | |
615 | err = ip_route_input(skb_in, fl.fl4_dst, fl.fl4_src, | |
616 | RT_TOS(tos), rt2->u.dst.dev); | |
617 | ||
618 | dst_release(&rt2->u.dst); | |
619 | rt2 = (struct rtable *)skb_in->dst; | |
620 | skb_in->dst = odst; | |
621 | } | |
622 | ||
623 | if (err) | |
624 | goto out_unlock; | |
625 | ||
626 | err = xfrm_lookup((struct dst_entry **)&rt2, &fl, NULL, | |
627 | XFRM_LOOKUP_ICMP); | |
628 | if (err == -ENOENT) { | |
629 | if (!rt) | |
630 | goto out_unlock; | |
631 | goto route_done; | |
632 | } | |
633 | ||
634 | dst_release(&rt->u.dst); | |
635 | rt = rt2; | |
636 | ||
637 | if (err) | |
1da177e4 LT |
638 | goto out_unlock; |
639 | } | |
640 | ||
8b7817f3 | 641 | route_done: |
1da177e4 LT |
642 | if (!icmpv4_xrlim_allow(rt, type, code)) |
643 | goto ende; | |
644 | ||
645 | /* RFC says return as much as we can without exceeding 576 bytes. */ | |
646 | ||
647 | room = dst_mtu(&rt->u.dst); | |
648 | if (room > 576) | |
649 | room = 576; | |
650 | room -= sizeof(struct iphdr) + icmp_param.replyopts.optlen; | |
651 | room -= sizeof(struct icmphdr); | |
652 | ||
653 | icmp_param.data_len = skb_in->len - icmp_param.offset; | |
654 | if (icmp_param.data_len > room) | |
655 | icmp_param.data_len = room; | |
656 | icmp_param.head_len = sizeof(struct icmphdr); | |
657 | ||
658 | icmp_push_reply(&icmp_param, &ipc, rt); | |
659 | ende: | |
660 | ip_rt_put(rt); | |
661 | out_unlock: | |
405666db | 662 | icmp_xmit_unlock(sk); |
1da177e4 LT |
663 | out:; |
664 | } | |
665 | ||
666 | ||
667 | /* | |
668 | * Handle ICMP_DEST_UNREACH, ICMP_TIME_EXCEED, and ICMP_QUENCH. | |
669 | */ | |
670 | ||
671 | static void icmp_unreach(struct sk_buff *skb) | |
672 | { | |
673 | struct iphdr *iph; | |
674 | struct icmphdr *icmph; | |
675 | int hash, protocol; | |
676 | struct net_protocol *ipprot; | |
1da177e4 | 677 | u32 info = 0; |
dde1bc0e DL |
678 | struct net *net; |
679 | ||
680 | net = skb->dst->dev->nd_net; | |
1da177e4 LT |
681 | |
682 | /* | |
683 | * Incomplete header ? | |
684 | * Only checks for the IP header, there should be an | |
685 | * additional check for longer headers in upper levels. | |
686 | */ | |
687 | ||
688 | if (!pskb_may_pull(skb, sizeof(struct iphdr))) | |
689 | goto out_err; | |
690 | ||
88c7664f | 691 | icmph = icmp_hdr(skb); |
1da177e4 LT |
692 | iph = (struct iphdr *)skb->data; |
693 | ||
694 | if (iph->ihl < 5) /* Mangled header, drop. */ | |
695 | goto out_err; | |
696 | ||
697 | if (icmph->type == ICMP_DEST_UNREACH) { | |
698 | switch (icmph->code & 15) { | |
699 | case ICMP_NET_UNREACH: | |
700 | case ICMP_HOST_UNREACH: | |
701 | case ICMP_PROT_UNREACH: | |
702 | case ICMP_PORT_UNREACH: | |
703 | break; | |
704 | case ICMP_FRAG_NEEDED: | |
705 | if (ipv4_config.no_pmtu_disc) { | |
64ce2073 | 706 | LIMIT_NETDEBUG(KERN_INFO "ICMP: %u.%u.%u.%u: " |
1da177e4 LT |
707 | "fragmentation needed " |
708 | "and DF set.\n", | |
64ce2073 | 709 | NIPQUAD(iph->daddr)); |
1da177e4 | 710 | } else { |
dde1bc0e | 711 | info = ip_rt_frag_needed(net, iph, |
1da177e4 LT |
712 | ntohs(icmph->un.frag.mtu)); |
713 | if (!info) | |
714 | goto out; | |
715 | } | |
716 | break; | |
717 | case ICMP_SR_FAILED: | |
64ce2073 | 718 | LIMIT_NETDEBUG(KERN_INFO "ICMP: %u.%u.%u.%u: Source " |
1da177e4 | 719 | "Route Failed.\n", |
64ce2073 | 720 | NIPQUAD(iph->daddr)); |
1da177e4 LT |
721 | break; |
722 | default: | |
723 | break; | |
724 | } | |
725 | if (icmph->code > NR_ICMP_UNREACH) | |
726 | goto out; | |
727 | } else if (icmph->type == ICMP_PARAMETERPROB) | |
728 | info = ntohl(icmph->un.gateway) >> 24; | |
729 | ||
730 | /* | |
731 | * Throw it at our lower layers | |
732 | * | |
733 | * RFC 1122: 3.2.2 MUST extract the protocol ID from the passed | |
734 | * header. | |
735 | * RFC 1122: 3.2.2.1 MUST pass ICMP unreach messages to the | |
736 | * transport layer. | |
737 | * RFC 1122: 3.2.2.2 MUST pass ICMP time expired messages to | |
738 | * transport layer. | |
739 | */ | |
740 | ||
741 | /* | |
742 | * Check the other end isnt violating RFC 1122. Some routers send | |
743 | * bogus responses to broadcast frames. If you see this message | |
744 | * first check your netmask matches at both ends, if it does then | |
745 | * get the other vendor to fix their kit. | |
746 | */ | |
747 | ||
748 | if (!sysctl_icmp_ignore_bogus_error_responses && | |
dde1bc0e | 749 | inet_addr_type(net, iph->daddr) == RTN_BROADCAST) { |
1da177e4 LT |
750 | if (net_ratelimit()) |
751 | printk(KERN_WARNING "%u.%u.%u.%u sent an invalid ICMP " | |
752 | "type %u, code %u " | |
753 | "error to a broadcast: %u.%u.%u.%u on %s\n", | |
eddc9ec5 | 754 | NIPQUAD(ip_hdr(skb)->saddr), |
1da177e4 LT |
755 | icmph->type, icmph->code, |
756 | NIPQUAD(iph->daddr), | |
757 | skb->dev->name); | |
758 | goto out; | |
759 | } | |
760 | ||
761 | /* Checkin full IP header plus 8 bytes of protocol to | |
762 | * avoid additional coding at protocol handlers. | |
763 | */ | |
764 | if (!pskb_may_pull(skb, iph->ihl * 4 + 8)) | |
765 | goto out; | |
766 | ||
767 | iph = (struct iphdr *)skb->data; | |
768 | protocol = iph->protocol; | |
769 | ||
770 | /* | |
771 | * Deliver ICMP message to raw sockets. Pretty useless feature? | |
772 | */ | |
7bc54c90 | 773 | raw_icmp_error(skb, protocol, info); |
1da177e4 | 774 | |
1da177e4 | 775 | hash = protocol & (MAX_INET_PROTOS - 1); |
1da177e4 LT |
776 | rcu_read_lock(); |
777 | ipprot = rcu_dereference(inet_protos[hash]); | |
778 | if (ipprot && ipprot->err_handler) | |
779 | ipprot->err_handler(skb, info); | |
780 | rcu_read_unlock(); | |
781 | ||
782 | out: | |
783 | return; | |
784 | out_err: | |
785 | ICMP_INC_STATS_BH(ICMP_MIB_INERRORS); | |
786 | goto out; | |
787 | } | |
788 | ||
789 | ||
790 | /* | |
791 | * Handle ICMP_REDIRECT. | |
792 | */ | |
793 | ||
794 | static void icmp_redirect(struct sk_buff *skb) | |
795 | { | |
796 | struct iphdr *iph; | |
1da177e4 LT |
797 | |
798 | if (skb->len < sizeof(struct iphdr)) | |
799 | goto out_err; | |
800 | ||
801 | /* | |
802 | * Get the copied header of the packet that caused the redirect | |
803 | */ | |
804 | if (!pskb_may_pull(skb, sizeof(struct iphdr))) | |
805 | goto out; | |
806 | ||
807 | iph = (struct iphdr *)skb->data; | |
1da177e4 | 808 | |
88c7664f | 809 | switch (icmp_hdr(skb)->code & 7) { |
1da177e4 LT |
810 | case ICMP_REDIR_NET: |
811 | case ICMP_REDIR_NETTOS: | |
812 | /* | |
813 | * As per RFC recommendations now handle it as a host redirect. | |
814 | */ | |
815 | case ICMP_REDIR_HOST: | |
816 | case ICMP_REDIR_HOSTTOS: | |
eddc9ec5 | 817 | ip_rt_redirect(ip_hdr(skb)->saddr, iph->daddr, |
88c7664f | 818 | icmp_hdr(skb)->un.gateway, |
cef2685e | 819 | iph->saddr, skb->dev); |
1da177e4 | 820 | break; |
e905a9ed | 821 | } |
1da177e4 LT |
822 | out: |
823 | return; | |
824 | out_err: | |
825 | ICMP_INC_STATS_BH(ICMP_MIB_INERRORS); | |
826 | goto out; | |
827 | } | |
828 | ||
829 | /* | |
830 | * Handle ICMP_ECHO ("ping") requests. | |
831 | * | |
832 | * RFC 1122: 3.2.2.6 MUST have an echo server that answers ICMP echo | |
833 | * requests. | |
834 | * RFC 1122: 3.2.2.6 Data received in the ICMP_ECHO request MUST be | |
835 | * included in the reply. | |
836 | * RFC 1812: 4.3.3.6 SHOULD have a config option for silently ignoring | |
837 | * echo requests, MUST have default=NOT. | |
838 | * See also WRT handling of options once they are done and working. | |
839 | */ | |
840 | ||
841 | static void icmp_echo(struct sk_buff *skb) | |
842 | { | |
843 | if (!sysctl_icmp_echo_ignore_all) { | |
844 | struct icmp_bxm icmp_param; | |
845 | ||
88c7664f | 846 | icmp_param.data.icmph = *icmp_hdr(skb); |
1da177e4 LT |
847 | icmp_param.data.icmph.type = ICMP_ECHOREPLY; |
848 | icmp_param.skb = skb; | |
849 | icmp_param.offset = 0; | |
850 | icmp_param.data_len = skb->len; | |
851 | icmp_param.head_len = sizeof(struct icmphdr); | |
852 | icmp_reply(&icmp_param, skb); | |
853 | } | |
854 | } | |
855 | ||
856 | /* | |
857 | * Handle ICMP Timestamp requests. | |
858 | * RFC 1122: 3.2.2.8 MAY implement ICMP timestamp requests. | |
859 | * SHOULD be in the kernel for minimum random latency. | |
860 | * MUST be accurate to a few minutes. | |
861 | * MUST be updated at least at 15Hz. | |
862 | */ | |
863 | static void icmp_timestamp(struct sk_buff *skb) | |
864 | { | |
865 | struct timeval tv; | |
866 | struct icmp_bxm icmp_param; | |
867 | /* | |
868 | * Too short. | |
869 | */ | |
870 | if (skb->len < 4) | |
871 | goto out_err; | |
872 | ||
873 | /* | |
874 | * Fill in the current time as ms since midnight UT: | |
875 | */ | |
876 | do_gettimeofday(&tv); | |
877 | icmp_param.data.times[1] = htonl((tv.tv_sec % 86400) * 1000 + | |
878 | tv.tv_usec / 1000); | |
879 | icmp_param.data.times[2] = icmp_param.data.times[1]; | |
880 | if (skb_copy_bits(skb, 0, &icmp_param.data.times[0], 4)) | |
881 | BUG(); | |
88c7664f | 882 | icmp_param.data.icmph = *icmp_hdr(skb); |
1da177e4 LT |
883 | icmp_param.data.icmph.type = ICMP_TIMESTAMPREPLY; |
884 | icmp_param.data.icmph.code = 0; | |
885 | icmp_param.skb = skb; | |
886 | icmp_param.offset = 0; | |
887 | icmp_param.data_len = 0; | |
888 | icmp_param.head_len = sizeof(struct icmphdr) + 12; | |
889 | icmp_reply(&icmp_param, skb); | |
890 | out: | |
891 | return; | |
892 | out_err: | |
893 | ICMP_INC_STATS_BH(ICMP_MIB_INERRORS); | |
894 | goto out; | |
895 | } | |
896 | ||
897 | ||
898 | /* | |
899 | * Handle ICMP_ADDRESS_MASK requests. (RFC950) | |
900 | * | |
901 | * RFC1122 (3.2.2.9). A host MUST only send replies to | |
902 | * ADDRESS_MASK requests if it's been configured as an address mask | |
903 | * agent. Receiving a request doesn't constitute implicit permission to | |
904 | * act as one. Of course, implementing this correctly requires (SHOULD) | |
905 | * a way to turn the functionality on and off. Another one for sysctl(), | |
906 | * I guess. -- MS | |
907 | * | |
908 | * RFC1812 (4.3.3.9). A router MUST implement it. | |
909 | * A router SHOULD have switch turning it on/off. | |
910 | * This switch MUST be ON by default. | |
911 | * | |
912 | * Gratuitous replies, zero-source replies are not implemented, | |
913 | * that complies with RFC. DO NOT implement them!!! All the idea | |
914 | * of broadcast addrmask replies as specified in RFC950 is broken. | |
915 | * The problem is that it is not uncommon to have several prefixes | |
916 | * on one physical interface. Moreover, addrmask agent can even be | |
917 | * not aware of existing another prefixes. | |
918 | * If source is zero, addrmask agent cannot choose correct prefix. | |
919 | * Gratuitous mask announcements suffer from the same problem. | |
920 | * RFC1812 explains it, but still allows to use ADDRMASK, | |
921 | * that is pretty silly. --ANK | |
922 | * | |
923 | * All these rules are so bizarre, that I removed kernel addrmask | |
924 | * support at all. It is wrong, it is obsolete, nobody uses it in | |
925 | * any case. --ANK | |
926 | * | |
927 | * Furthermore you can do it with a usermode address agent program | |
928 | * anyway... | |
929 | */ | |
930 | ||
931 | static void icmp_address(struct sk_buff *skb) | |
932 | { | |
933 | #if 0 | |
934 | if (net_ratelimit()) | |
935 | printk(KERN_DEBUG "a guy asks for address mask. Who is it?\n"); | |
936 | #endif | |
937 | } | |
938 | ||
939 | /* | |
940 | * RFC1812 (4.3.3.9). A router SHOULD listen all replies, and complain | |
941 | * loudly if an inconsistency is found. | |
942 | */ | |
943 | ||
944 | static void icmp_address_reply(struct sk_buff *skb) | |
945 | { | |
946 | struct rtable *rt = (struct rtable *)skb->dst; | |
947 | struct net_device *dev = skb->dev; | |
948 | struct in_device *in_dev; | |
949 | struct in_ifaddr *ifa; | |
950 | ||
951 | if (skb->len < 4 || !(rt->rt_flags&RTCF_DIRECTSRC)) | |
952 | goto out; | |
953 | ||
954 | in_dev = in_dev_get(dev); | |
955 | if (!in_dev) | |
956 | goto out; | |
957 | rcu_read_lock(); | |
958 | if (in_dev->ifa_list && | |
959 | IN_DEV_LOG_MARTIANS(in_dev) && | |
960 | IN_DEV_FORWARD(in_dev)) { | |
a144ea4b | 961 | __be32 _mask, *mp; |
1da177e4 LT |
962 | |
963 | mp = skb_header_pointer(skb, 0, sizeof(_mask), &_mask); | |
09a62660 | 964 | BUG_ON(mp == NULL); |
1da177e4 LT |
965 | for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) { |
966 | if (*mp == ifa->ifa_mask && | |
967 | inet_ifa_match(rt->rt_src, ifa)) | |
968 | break; | |
969 | } | |
970 | if (!ifa && net_ratelimit()) { | |
971 | printk(KERN_INFO "Wrong address mask %u.%u.%u.%u from " | |
972 | "%s/%u.%u.%u.%u\n", | |
973 | NIPQUAD(*mp), dev->name, NIPQUAD(rt->rt_src)); | |
974 | } | |
975 | } | |
976 | rcu_read_unlock(); | |
977 | in_dev_put(in_dev); | |
978 | out:; | |
979 | } | |
980 | ||
981 | static void icmp_discard(struct sk_buff *skb) | |
982 | { | |
983 | } | |
984 | ||
985 | /* | |
986 | * Deal with incoming ICMP packets. | |
987 | */ | |
988 | int icmp_rcv(struct sk_buff *skb) | |
989 | { | |
990 | struct icmphdr *icmph; | |
991 | struct rtable *rt = (struct rtable *)skb->dst; | |
992 | ||
aebcf82c | 993 | if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb)) { |
8b7817f3 HX |
994 | int nh; |
995 | ||
aebcf82c HX |
996 | if (!(skb->sp && skb->sp->xvec[skb->sp->len - 1]->props.flags & |
997 | XFRM_STATE_ICMP)) | |
998 | goto drop; | |
999 | ||
8b7817f3 HX |
1000 | if (!pskb_may_pull(skb, sizeof(*icmph) + sizeof(struct iphdr))) |
1001 | goto drop; | |
1002 | ||
1003 | nh = skb_network_offset(skb); | |
1004 | skb_set_network_header(skb, sizeof(*icmph)); | |
1005 | ||
1006 | if (!xfrm4_policy_check_reverse(NULL, XFRM_POLICY_IN, skb)) | |
1007 | goto drop; | |
1008 | ||
1009 | skb_set_network_header(skb, nh); | |
1010 | } | |
1011 | ||
1da177e4 LT |
1012 | ICMP_INC_STATS_BH(ICMP_MIB_INMSGS); |
1013 | ||
1014 | switch (skb->ip_summed) { | |
84fa7933 | 1015 | case CHECKSUM_COMPLETE: |
d3bc23e7 | 1016 | if (!csum_fold(skb->csum)) |
1da177e4 | 1017 | break; |
fb286bb2 | 1018 | /* fall through */ |
1da177e4 | 1019 | case CHECKSUM_NONE: |
fb286bb2 HX |
1020 | skb->csum = 0; |
1021 | if (__skb_checksum_complete(skb)) | |
1da177e4 | 1022 | goto error; |
1da177e4 LT |
1023 | } |
1024 | ||
8cf22943 HX |
1025 | if (!pskb_pull(skb, sizeof(*icmph))) |
1026 | goto error; | |
1da177e4 | 1027 | |
88c7664f | 1028 | icmph = icmp_hdr(skb); |
1da177e4 | 1029 | |
96793b48 | 1030 | ICMPMSGIN_INC_STATS_BH(icmph->type); |
1da177e4 LT |
1031 | /* |
1032 | * 18 is the highest 'known' ICMP type. Anything else is a mystery | |
1033 | * | |
1034 | * RFC 1122: 3.2.2 Unknown ICMP messages types MUST be silently | |
1035 | * discarded. | |
1036 | */ | |
1037 | if (icmph->type > NR_ICMP_TYPES) | |
1038 | goto error; | |
1039 | ||
1040 | ||
1041 | /* | |
1042 | * Parse the ICMP message | |
1043 | */ | |
1044 | ||
e905a9ed | 1045 | if (rt->rt_flags & (RTCF_BROADCAST | RTCF_MULTICAST)) { |
1da177e4 LT |
1046 | /* |
1047 | * RFC 1122: 3.2.2.6 An ICMP_ECHO to broadcast MAY be | |
1048 | * silently ignored (we let user decide with a sysctl). | |
1049 | * RFC 1122: 3.2.2.8 An ICMP_TIMESTAMP MAY be silently | |
1050 | * discarded if to broadcast/multicast. | |
1051 | */ | |
4c866aa7 AK |
1052 | if ((icmph->type == ICMP_ECHO || |
1053 | icmph->type == ICMP_TIMESTAMP) && | |
1da177e4 LT |
1054 | sysctl_icmp_echo_ignore_broadcasts) { |
1055 | goto error; | |
1056 | } | |
1057 | if (icmph->type != ICMP_ECHO && | |
1058 | icmph->type != ICMP_TIMESTAMP && | |
1059 | icmph->type != ICMP_ADDRESS && | |
1060 | icmph->type != ICMP_ADDRESSREPLY) { | |
1061 | goto error; | |
e905a9ed | 1062 | } |
1da177e4 LT |
1063 | } |
1064 | ||
1da177e4 LT |
1065 | icmp_pointers[icmph->type].handler(skb); |
1066 | ||
1067 | drop: | |
1068 | kfree_skb(skb); | |
1069 | return 0; | |
1070 | error: | |
1071 | ICMP_INC_STATS_BH(ICMP_MIB_INERRORS); | |
1072 | goto drop; | |
1073 | } | |
1074 | ||
1075 | /* | |
1076 | * This table is the definition of how we handle ICMP. | |
1077 | */ | |
9b5b5cff | 1078 | static const struct icmp_control icmp_pointers[NR_ICMP_TYPES + 1] = { |
1da177e4 | 1079 | [ICMP_ECHOREPLY] = { |
1da177e4 LT |
1080 | .handler = icmp_discard, |
1081 | }, | |
1082 | [1] = { | |
1da177e4 LT |
1083 | .handler = icmp_discard, |
1084 | .error = 1, | |
1085 | }, | |
1086 | [2] = { | |
1da177e4 LT |
1087 | .handler = icmp_discard, |
1088 | .error = 1, | |
1089 | }, | |
1090 | [ICMP_DEST_UNREACH] = { | |
1da177e4 LT |
1091 | .handler = icmp_unreach, |
1092 | .error = 1, | |
1093 | }, | |
1094 | [ICMP_SOURCE_QUENCH] = { | |
1da177e4 LT |
1095 | .handler = icmp_unreach, |
1096 | .error = 1, | |
1097 | }, | |
1098 | [ICMP_REDIRECT] = { | |
1da177e4 LT |
1099 | .handler = icmp_redirect, |
1100 | .error = 1, | |
1101 | }, | |
1102 | [6] = { | |
1da177e4 LT |
1103 | .handler = icmp_discard, |
1104 | .error = 1, | |
1105 | }, | |
1106 | [7] = { | |
1da177e4 LT |
1107 | .handler = icmp_discard, |
1108 | .error = 1, | |
1109 | }, | |
1110 | [ICMP_ECHO] = { | |
1da177e4 LT |
1111 | .handler = icmp_echo, |
1112 | }, | |
1113 | [9] = { | |
1da177e4 LT |
1114 | .handler = icmp_discard, |
1115 | .error = 1, | |
1116 | }, | |
1117 | [10] = { | |
1da177e4 LT |
1118 | .handler = icmp_discard, |
1119 | .error = 1, | |
1120 | }, | |
1121 | [ICMP_TIME_EXCEEDED] = { | |
1da177e4 LT |
1122 | .handler = icmp_unreach, |
1123 | .error = 1, | |
1124 | }, | |
1125 | [ICMP_PARAMETERPROB] = { | |
1da177e4 LT |
1126 | .handler = icmp_unreach, |
1127 | .error = 1, | |
1128 | }, | |
1129 | [ICMP_TIMESTAMP] = { | |
1da177e4 LT |
1130 | .handler = icmp_timestamp, |
1131 | }, | |
1132 | [ICMP_TIMESTAMPREPLY] = { | |
1da177e4 LT |
1133 | .handler = icmp_discard, |
1134 | }, | |
1135 | [ICMP_INFO_REQUEST] = { | |
1da177e4 LT |
1136 | .handler = icmp_discard, |
1137 | }, | |
e905a9ed | 1138 | [ICMP_INFO_REPLY] = { |
1da177e4 LT |
1139 | .handler = icmp_discard, |
1140 | }, | |
1141 | [ICMP_ADDRESS] = { | |
1da177e4 LT |
1142 | .handler = icmp_address, |
1143 | }, | |
1144 | [ICMP_ADDRESSREPLY] = { | |
1da177e4 LT |
1145 | .handler = icmp_address_reply, |
1146 | }, | |
1147 | }; | |
1148 | ||
4a6ad7a1 | 1149 | static void __net_exit icmp_sk_exit(struct net *net) |
1da177e4 | 1150 | { |
1da177e4 LT |
1151 | int i; |
1152 | ||
5c8cafd6 | 1153 | for_each_possible_cpu(i) |
4a6ad7a1 DL |
1154 | sk_release_kernel(net->ipv4.icmp_sk[i]); |
1155 | kfree(net->ipv4.icmp_sk); | |
1156 | net->ipv4.icmp_sk = NULL; | |
a5710d65 | 1157 | } |
1da177e4 | 1158 | |
4a6ad7a1 | 1159 | int __net_init icmp_sk_init(struct net *net) |
a5710d65 | 1160 | { |
a5710d65 DL |
1161 | int i, err; |
1162 | ||
4a6ad7a1 DL |
1163 | net->ipv4.icmp_sk = |
1164 | kzalloc(nr_cpu_ids * sizeof(struct sock *), GFP_KERNEL); | |
1165 | if (net->ipv4.icmp_sk == NULL) | |
79c91159 DL |
1166 | return -ENOMEM; |
1167 | ||
a5710d65 | 1168 | for_each_possible_cpu(i) { |
1e3cf683 DL |
1169 | struct sock *sk; |
1170 | struct socket *sock; | |
1171 | struct inet_sock *inet; | |
1da177e4 | 1172 | |
1e3cf683 | 1173 | err = sock_create_kern(PF_INET, SOCK_RAW, IPPROTO_ICMP, &sock); |
1da177e4 | 1174 | if (err < 0) |
a5710d65 | 1175 | goto fail; |
1da177e4 | 1176 | |
4a6ad7a1 DL |
1177 | net->ipv4.icmp_sk[i] = sk = sock->sk; |
1178 | sk_change_net(sk, net); | |
5c8cafd6 | 1179 | |
1e3cf683 | 1180 | sk->sk_allocation = GFP_ATOMIC; |
1da177e4 LT |
1181 | |
1182 | /* Enough space for 2 64K ICMP packets, including | |
1183 | * sk_buff struct overhead. | |
1184 | */ | |
1e3cf683 | 1185 | sk->sk_sndbuf = |
1da177e4 LT |
1186 | (2 * ((64 * 1024) + sizeof(struct sk_buff))); |
1187 | ||
1e3cf683 | 1188 | inet = inet_sk(sk); |
1da177e4 LT |
1189 | inet->uc_ttl = -1; |
1190 | inet->pmtudisc = IP_PMTUDISC_DONT; | |
1191 | ||
1192 | /* Unhash it so that IP input processing does not even | |
1193 | * see it, we do not wish this socket to see incoming | |
1194 | * packets. | |
1195 | */ | |
1e3cf683 | 1196 | sk->sk_prot->unhash(sk); |
1da177e4 | 1197 | } |
a5710d65 DL |
1198 | return 0; |
1199 | ||
1200 | fail: | |
4a6ad7a1 | 1201 | icmp_sk_exit(net); |
a5710d65 | 1202 | return err; |
1da177e4 LT |
1203 | } |
1204 | ||
4a6ad7a1 DL |
1205 | static struct pernet_operations __net_initdata icmp_sk_ops = { |
1206 | .init = icmp_sk_init, | |
1207 | .exit = icmp_sk_exit, | |
1208 | }; | |
1209 | ||
1210 | int __init icmp_init(void) | |
1211 | { | |
1212 | return register_pernet_device(&icmp_sk_ops); | |
1213 | } | |
1214 | ||
1da177e4 LT |
1215 | EXPORT_SYMBOL(icmp_err_convert); |
1216 | EXPORT_SYMBOL(icmp_send); | |
1217 | EXPORT_SYMBOL(icmp_statistics); | |
1218 | EXPORT_SYMBOL(xrlim_allow); |