Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * NET3: Implementation of the ICMP protocol layer. | |
3 | * | |
113aa838 | 4 | * Alan Cox, <alan@lxorguk.ukuu.org.uk> |
1da177e4 | 5 | * |
1da177e4 LT |
6 | * This program is free software; you can redistribute it and/or |
7 | * modify it under the terms of the GNU General Public License | |
8 | * as published by the Free Software Foundation; either version | |
9 | * 2 of the License, or (at your option) any later version. | |
10 | * | |
11 | * Some of the function names and the icmp unreach table for this | |
12 | * module were derived from [icmp.c 1.0.11 06/02/93] by | |
13 | * Ross Biro, Fred N. van Kempen, Mark Evans, Alan Cox, Gerhard Koerting. | |
14 | * Other than that this module is a complete rewrite. | |
15 | * | |
16 | * Fixes: | |
17 | * Clemens Fruhwirth : introduce global icmp rate limiting | |
18 | * with icmp type masking ability instead | |
19 | * of broken per type icmp timeouts. | |
20 | * Mike Shaver : RFC1122 checks. | |
21 | * Alan Cox : Multicast ping reply as self. | |
22 | * Alan Cox : Fix atomicity lockup in ip_build_xmit | |
23 | * call. | |
24 | * Alan Cox : Added 216,128 byte paths to the MTU | |
25 | * code. | |
26 | * Martin Mares : RFC1812 checks. | |
27 | * Martin Mares : Can be configured to follow redirects | |
28 | * if acting as a router _without_ a | |
29 | * routing protocol (RFC 1812). | |
30 | * Martin Mares : Echo requests may be configured to | |
31 | * be ignored (RFC 1812). | |
32 | * Martin Mares : Limitation of ICMP error message | |
33 | * transmit rate (RFC 1812). | |
34 | * Martin Mares : TOS and Precedence set correctly | |
35 | * (RFC 1812). | |
36 | * Martin Mares : Now copying as much data from the | |
37 | * original packet as we can without | |
38 | * exceeding 576 bytes (RFC 1812). | |
39 | * Willy Konynenberg : Transparent proxying support. | |
40 | * Keith Owens : RFC1191 correction for 4.2BSD based | |
41 | * path MTU bug. | |
42 | * Thomas Quinot : ICMP Dest Unreach codes up to 15 are | |
43 | * valid (RFC 1812). | |
44 | * Andi Kleen : Check all packet lengths properly | |
45 | * and moved all kfree_skb() up to | |
46 | * icmp_rcv. | |
47 | * Andi Kleen : Move the rate limit bookkeeping | |
48 | * into the dest entry and use a token | |
49 | * bucket filter (thanks to ANK). Make | |
50 | * the rates sysctl configurable. | |
51 | * Yu Tianli : Fixed two ugly bugs in icmp_send | |
52 | * - IP option length was accounted wrongly | |
53 | * - ICMP header length was not accounted | |
54 | * at all. | |
55 | * Tristan Greaves : Added sysctl option to ignore bogus | |
56 | * broadcast responses from broken routers. | |
57 | * | |
58 | * To Fix: | |
59 | * | |
60 | * - Should use skb_pull() instead of all the manual checking. | |
61 | * This would also greatly simply some upper layer error handlers. --AK | |
62 | * | |
63 | */ | |
64 | ||
1da177e4 LT |
65 | #include <linux/module.h> |
66 | #include <linux/types.h> | |
67 | #include <linux/jiffies.h> | |
68 | #include <linux/kernel.h> | |
69 | #include <linux/fcntl.h> | |
70 | #include <linux/socket.h> | |
71 | #include <linux/in.h> | |
72 | #include <linux/inet.h> | |
14c85021 | 73 | #include <linux/inetdevice.h> |
1da177e4 LT |
74 | #include <linux/netdevice.h> |
75 | #include <linux/string.h> | |
76 | #include <linux/netfilter_ipv4.h> | |
5a0e3ad6 | 77 | #include <linux/slab.h> |
1da177e4 LT |
78 | #include <net/snmp.h> |
79 | #include <net/ip.h> | |
80 | #include <net/route.h> | |
81 | #include <net/protocol.h> | |
82 | #include <net/icmp.h> | |
83 | #include <net/tcp.h> | |
84 | #include <net/udp.h> | |
85 | #include <net/raw.h> | |
86 | #include <linux/skbuff.h> | |
87 | #include <net/sock.h> | |
88 | #include <linux/errno.h> | |
89 | #include <linux/timer.h> | |
90 | #include <linux/init.h> | |
91 | #include <asm/system.h> | |
92 | #include <asm/uaccess.h> | |
93 | #include <net/checksum.h> | |
8b7817f3 | 94 | #include <net/xfrm.h> |
c1e9894d | 95 | #include <net/inet_common.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 | ||
1da177e4 LT |
115 | /* An array of errno for error messages from dest unreach. */ |
116 | /* RFC 1122: 3.2.2.1 States that NET_UNREACH, HOST_UNREACH and SR_FAILED MUST be considered 'transient errs'. */ | |
117 | ||
e754834e | 118 | const struct icmp_err icmp_err_convert[] = { |
1da177e4 LT |
119 | { |
120 | .errno = ENETUNREACH, /* ICMP_NET_UNREACH */ | |
121 | .fatal = 0, | |
122 | }, | |
123 | { | |
124 | .errno = EHOSTUNREACH, /* ICMP_HOST_UNREACH */ | |
125 | .fatal = 0, | |
126 | }, | |
127 | { | |
128 | .errno = ENOPROTOOPT /* ICMP_PROT_UNREACH */, | |
129 | .fatal = 1, | |
130 | }, | |
131 | { | |
132 | .errno = ECONNREFUSED, /* ICMP_PORT_UNREACH */ | |
133 | .fatal = 1, | |
134 | }, | |
135 | { | |
136 | .errno = EMSGSIZE, /* ICMP_FRAG_NEEDED */ | |
137 | .fatal = 0, | |
138 | }, | |
139 | { | |
140 | .errno = EOPNOTSUPP, /* ICMP_SR_FAILED */ | |
141 | .fatal = 0, | |
142 | }, | |
143 | { | |
144 | .errno = ENETUNREACH, /* ICMP_NET_UNKNOWN */ | |
145 | .fatal = 1, | |
146 | }, | |
147 | { | |
148 | .errno = EHOSTDOWN, /* ICMP_HOST_UNKNOWN */ | |
149 | .fatal = 1, | |
150 | }, | |
151 | { | |
152 | .errno = ENONET, /* ICMP_HOST_ISOLATED */ | |
153 | .fatal = 1, | |
154 | }, | |
155 | { | |
156 | .errno = ENETUNREACH, /* ICMP_NET_ANO */ | |
157 | .fatal = 1, | |
158 | }, | |
159 | { | |
160 | .errno = EHOSTUNREACH, /* ICMP_HOST_ANO */ | |
161 | .fatal = 1, | |
162 | }, | |
163 | { | |
164 | .errno = ENETUNREACH, /* ICMP_NET_UNR_TOS */ | |
165 | .fatal = 0, | |
166 | }, | |
167 | { | |
168 | .errno = EHOSTUNREACH, /* ICMP_HOST_UNR_TOS */ | |
169 | .fatal = 0, | |
170 | }, | |
171 | { | |
172 | .errno = EHOSTUNREACH, /* ICMP_PKT_FILTERED */ | |
173 | .fatal = 1, | |
174 | }, | |
175 | { | |
176 | .errno = EHOSTUNREACH, /* ICMP_PREC_VIOLATION */ | |
177 | .fatal = 1, | |
178 | }, | |
179 | { | |
180 | .errno = EHOSTUNREACH, /* ICMP_PREC_CUTOFF */ | |
181 | .fatal = 1, | |
182 | }, | |
183 | }; | |
184 | ||
1da177e4 LT |
185 | /* |
186 | * ICMP control array. This specifies what to do with each ICMP. | |
187 | */ | |
188 | ||
189 | struct icmp_control { | |
1da177e4 LT |
190 | void (*handler)(struct sk_buff *skb); |
191 | short error; /* This ICMP is classed as an error message */ | |
192 | }; | |
193 | ||
9b5b5cff | 194 | static const struct icmp_control icmp_pointers[NR_ICMP_TYPES+1]; |
1da177e4 LT |
195 | |
196 | /* | |
197 | * The ICMP socket(s). This is the most convenient way to flow control | |
198 | * our ICMP output as well as maintain a clean interface throughout | |
199 | * all layers. All Socketless IP sends will soon be gone. | |
200 | * | |
201 | * On SMP we have one ICMP socket per-cpu. | |
202 | */ | |
4a6ad7a1 DL |
203 | static struct sock *icmp_sk(struct net *net) |
204 | { | |
205 | return net->ipv4.icmp_sk[smp_processor_id()]; | |
206 | } | |
1da177e4 | 207 | |
fdc0bde9 | 208 | static inline struct sock *icmp_xmit_lock(struct net *net) |
1da177e4 | 209 | { |
fdc0bde9 DL |
210 | struct sock *sk; |
211 | ||
1da177e4 LT |
212 | local_bh_disable(); |
213 | ||
fdc0bde9 DL |
214 | sk = icmp_sk(net); |
215 | ||
405666db | 216 | if (unlikely(!spin_trylock(&sk->sk_lock.slock))) { |
1da177e4 LT |
217 | /* This can happen if the output path signals a |
218 | * dst_link_failure() for an outgoing ICMP packet. | |
219 | */ | |
220 | local_bh_enable(); | |
fdc0bde9 | 221 | return NULL; |
1da177e4 | 222 | } |
fdc0bde9 | 223 | return sk; |
1da177e4 LT |
224 | } |
225 | ||
405666db | 226 | static inline void icmp_xmit_unlock(struct sock *sk) |
1da177e4 | 227 | { |
405666db | 228 | spin_unlock_bh(&sk->sk_lock.slock); |
1da177e4 LT |
229 | } |
230 | ||
231 | /* | |
232 | * Send an ICMP frame. | |
233 | */ | |
234 | ||
235 | /* | |
236 | * Check transmit rate limitation for given message. | |
237 | * The rate information is held in the destination cache now. | |
238 | * This function is generic and could be used for other purposes | |
239 | * too. It uses a Token bucket filter as suggested by Alexey Kuznetsov. | |
240 | * | |
241 | * Note that the same dst_entry fields are modified by functions in | |
242 | * route.c too, but these work for packet destinations while xrlim_allow | |
243 | * works for icmp destinations. This means the rate limiting information | |
244 | * for one "ip object" is shared - and these ICMPs are twice limited: | |
245 | * by source and by destination. | |
246 | * | |
247 | * RFC 1812: 4.3.2.8 SHOULD be able to limit error message rate | |
248 | * SHOULD allow setting of rate limits | |
249 | * | |
250 | * Shared between ICMPv4 and ICMPv6. | |
251 | */ | |
252 | #define XRLIM_BURST_FACTOR 6 | |
253 | int xrlim_allow(struct dst_entry *dst, int timeout) | |
254 | { | |
69a73829 | 255 | unsigned long now, token = dst->rate_tokens; |
1da177e4 LT |
256 | int rc = 0; |
257 | ||
258 | now = jiffies; | |
69a73829 | 259 | token += now - dst->rate_last; |
1da177e4 | 260 | dst->rate_last = now; |
69a73829 ED |
261 | if (token > XRLIM_BURST_FACTOR * timeout) |
262 | token = XRLIM_BURST_FACTOR * timeout; | |
263 | if (token >= timeout) { | |
264 | token -= timeout; | |
1da177e4 LT |
265 | rc = 1; |
266 | } | |
69a73829 | 267 | dst->rate_tokens = token; |
1da177e4 LT |
268 | return rc; |
269 | } | |
270 | ||
b34a95ee PE |
271 | static inline int icmpv4_xrlim_allow(struct net *net, struct rtable *rt, |
272 | int type, int code) | |
1da177e4 LT |
273 | { |
274 | struct dst_entry *dst = &rt->u.dst; | |
275 | int rc = 1; | |
276 | ||
277 | if (type > NR_ICMP_TYPES) | |
278 | goto out; | |
279 | ||
280 | /* Don't limit PMTU discovery. */ | |
281 | if (type == ICMP_DEST_UNREACH && code == ICMP_FRAG_NEEDED) | |
282 | goto out; | |
283 | ||
284 | /* No rate limit on loopback */ | |
285 | if (dst->dev && (dst->dev->flags&IFF_LOOPBACK)) | |
e905a9ed | 286 | goto out; |
1da177e4 LT |
287 | |
288 | /* Limit if icmp type is enabled in ratemask. */ | |
b34a95ee PE |
289 | if ((1 << type) & net->ipv4.sysctl_icmp_ratemask) |
290 | rc = xrlim_allow(dst, net->ipv4.sysctl_icmp_ratelimit); | |
1da177e4 LT |
291 | out: |
292 | return rc; | |
293 | } | |
294 | ||
295 | /* | |
296 | * Maintain the counters used in the SNMP statistics for outgoing ICMP | |
297 | */ | |
0388b004 | 298 | void icmp_out_count(struct net *net, unsigned char type) |
1da177e4 | 299 | { |
903fc196 | 300 | ICMPMSGOUT_INC_STATS(net, type); |
75c939bb | 301 | ICMP_INC_STATS(net, ICMP_MIB_OUTMSGS); |
1da177e4 LT |
302 | } |
303 | ||
304 | /* | |
305 | * Checksum each fragment, and on the first include the headers and final | |
306 | * checksum. | |
307 | */ | |
308 | static int icmp_glue_bits(void *from, char *to, int offset, int len, int odd, | |
309 | struct sk_buff *skb) | |
310 | { | |
311 | struct icmp_bxm *icmp_param = (struct icmp_bxm *)from; | |
5f92a738 | 312 | __wsum csum; |
1da177e4 LT |
313 | |
314 | csum = skb_copy_and_csum_bits(icmp_param->skb, | |
315 | icmp_param->offset + offset, | |
316 | to, len, 0); | |
317 | ||
318 | skb->csum = csum_block_add(skb->csum, csum, odd); | |
319 | if (icmp_pointers[icmp_param->data.icmph.type].error) | |
320 | nf_ct_attach(skb, icmp_param->skb); | |
321 | return 0; | |
322 | } | |
323 | ||
324 | static void icmp_push_reply(struct icmp_bxm *icmp_param, | |
2e77d89b | 325 | struct ipcm_cookie *ipc, struct rtable **rt) |
1da177e4 | 326 | { |
1e3cf683 | 327 | struct sock *sk; |
1da177e4 LT |
328 | struct sk_buff *skb; |
329 | ||
2e77d89b | 330 | sk = icmp_sk(dev_net((*rt)->u.dst.dev)); |
1e3cf683 | 331 | if (ip_append_data(sk, icmp_glue_bits, icmp_param, |
e905a9ed YH |
332 | icmp_param->data_len+icmp_param->head_len, |
333 | icmp_param->head_len, | |
334 | ipc, rt, MSG_DONTWAIT) < 0) | |
1e3cf683 DL |
335 | ip_flush_pending_frames(sk); |
336 | else if ((skb = skb_peek(&sk->sk_write_queue)) != NULL) { | |
88c7664f | 337 | struct icmphdr *icmph = icmp_hdr(skb); |
d3bc23e7 | 338 | __wsum csum = 0; |
1da177e4 LT |
339 | struct sk_buff *skb1; |
340 | ||
1e3cf683 | 341 | skb_queue_walk(&sk->sk_write_queue, skb1) { |
1da177e4 LT |
342 | csum = csum_add(csum, skb1->csum); |
343 | } | |
344 | csum = csum_partial_copy_nocheck((void *)&icmp_param->data, | |
345 | (char *)icmph, | |
346 | icmp_param->head_len, csum); | |
347 | icmph->checksum = csum_fold(csum); | |
348 | skb->ip_summed = CHECKSUM_NONE; | |
1e3cf683 | 349 | ip_push_pending_frames(sk); |
1da177e4 LT |
350 | } |
351 | } | |
352 | ||
353 | /* | |
354 | * Driving logic for building and sending ICMP messages. | |
355 | */ | |
356 | ||
357 | static void icmp_reply(struct icmp_bxm *icmp_param, struct sk_buff *skb) | |
358 | { | |
1da177e4 | 359 | struct ipcm_cookie ipc; |
511c3f92 | 360 | struct rtable *rt = skb_rtable(skb); |
c346dca1 | 361 | struct net *net = dev_net(rt->u.dst.dev); |
fdc0bde9 DL |
362 | struct sock *sk; |
363 | struct inet_sock *inet; | |
3ca3c68e | 364 | __be32 daddr; |
1da177e4 LT |
365 | |
366 | if (ip_options_echo(&icmp_param->replyopts, skb)) | |
f00c401b | 367 | return; |
1da177e4 | 368 | |
fdc0bde9 DL |
369 | sk = icmp_xmit_lock(net); |
370 | if (sk == NULL) | |
1da177e4 | 371 | return; |
fdc0bde9 | 372 | inet = inet_sk(sk); |
1da177e4 LT |
373 | |
374 | icmp_param->data.icmph.checksum = 0; | |
1da177e4 | 375 | |
eddc9ec5 | 376 | inet->tos = ip_hdr(skb)->tos; |
1da177e4 LT |
377 | daddr = ipc.addr = rt->rt_src; |
378 | ipc.opt = NULL; | |
51f31cab | 379 | ipc.shtx.flags = 0; |
1da177e4 LT |
380 | if (icmp_param->replyopts.optlen) { |
381 | ipc.opt = &icmp_param->replyopts; | |
382 | if (ipc.opt->srr) | |
383 | daddr = icmp_param->replyopts.faddr; | |
384 | } | |
385 | { | |
386 | struct flowi fl = { .nl_u = { .ip4_u = | |
387 | { .daddr = daddr, | |
388 | .saddr = rt->rt_spec_dst, | |
eddc9ec5 | 389 | .tos = RT_TOS(ip_hdr(skb)->tos) } }, |
1da177e4 | 390 | .proto = IPPROTO_ICMP }; |
beb8d13b | 391 | security_skb_classify_flow(skb, &fl); |
4a6ad7a1 | 392 | if (ip_route_output_key(net, &rt, &fl)) |
1da177e4 LT |
393 | goto out_unlock; |
394 | } | |
b34a95ee | 395 | if (icmpv4_xrlim_allow(net, rt, icmp_param->data.icmph.type, |
1da177e4 | 396 | icmp_param->data.icmph.code)) |
2e77d89b | 397 | icmp_push_reply(icmp_param, &ipc, &rt); |
1da177e4 LT |
398 | ip_rt_put(rt); |
399 | out_unlock: | |
405666db | 400 | icmp_xmit_unlock(sk); |
1da177e4 LT |
401 | } |
402 | ||
403 | ||
404 | /* | |
405 | * Send an ICMP message in response to a situation | |
406 | * | |
407 | * RFC 1122: 3.2.2 MUST send at least the IP header and 8 bytes of header. | |
408 | * MAY send more (we do). | |
409 | * MUST NOT change this header information. | |
410 | * MUST NOT reply to a multicast/broadcast IP address. | |
411 | * MUST NOT reply to a multicast/broadcast MAC address. | |
412 | * MUST reply to only the first fragment. | |
413 | */ | |
414 | ||
e4883014 | 415 | void icmp_send(struct sk_buff *skb_in, int type, int code, __be32 info) |
1da177e4 LT |
416 | { |
417 | struct iphdr *iph; | |
418 | int room; | |
419 | struct icmp_bxm icmp_param; | |
511c3f92 | 420 | struct rtable *rt = skb_rtable(skb_in); |
1da177e4 | 421 | struct ipcm_cookie ipc; |
a61ced5d | 422 | __be32 saddr; |
1da177e4 | 423 | u8 tos; |
dde1bc0e | 424 | struct net *net; |
4a6ad7a1 | 425 | struct sock *sk; |
1da177e4 LT |
426 | |
427 | if (!rt) | |
428 | goto out; | |
c346dca1 | 429 | net = dev_net(rt->u.dst.dev); |
1da177e4 LT |
430 | |
431 | /* | |
432 | * Find the original header. It is expected to be valid, of course. | |
433 | * Check this, icmp_send is called from the most obscure devices | |
434 | * sometimes. | |
435 | */ | |
eddc9ec5 | 436 | iph = ip_hdr(skb_in); |
1da177e4 | 437 | |
27a884dc ACM |
438 | if ((u8 *)iph < skb_in->head || |
439 | (skb_in->network_header + sizeof(*iph)) > skb_in->tail) | |
1da177e4 LT |
440 | goto out; |
441 | ||
442 | /* | |
443 | * No replies to physical multicast/broadcast | |
444 | */ | |
445 | if (skb_in->pkt_type != PACKET_HOST) | |
446 | goto out; | |
447 | ||
448 | /* | |
449 | * Now check at the protocol level | |
450 | */ | |
451 | if (rt->rt_flags & (RTCF_BROADCAST | RTCF_MULTICAST)) | |
452 | goto out; | |
453 | ||
454 | /* | |
455 | * Only reply to fragment 0. We byte re-order the constant | |
456 | * mask for efficiency. | |
457 | */ | |
458 | if (iph->frag_off & htons(IP_OFFSET)) | |
459 | goto out; | |
460 | ||
461 | /* | |
462 | * If we send an ICMP error to an ICMP error a mess would result.. | |
463 | */ | |
464 | if (icmp_pointers[type].error) { | |
465 | /* | |
466 | * We are an error, check if we are replying to an | |
467 | * ICMP error | |
468 | */ | |
469 | if (iph->protocol == IPPROTO_ICMP) { | |
470 | u8 _inner_type, *itp; | |
471 | ||
472 | itp = skb_header_pointer(skb_in, | |
d56f90a7 | 473 | skb_network_header(skb_in) + |
1da177e4 LT |
474 | (iph->ihl << 2) + |
475 | offsetof(struct icmphdr, | |
476 | type) - | |
477 | skb_in->data, | |
478 | sizeof(_inner_type), | |
479 | &_inner_type); | |
480 | if (itp == NULL) | |
481 | goto out; | |
482 | ||
483 | /* | |
484 | * Assume any unknown ICMP type is an error. This | |
485 | * isn't specified by the RFC, but think about it.. | |
486 | */ | |
487 | if (*itp > NR_ICMP_TYPES || | |
488 | icmp_pointers[*itp].error) | |
489 | goto out; | |
490 | } | |
491 | } | |
492 | ||
fdc0bde9 DL |
493 | sk = icmp_xmit_lock(net); |
494 | if (sk == NULL) | |
1da177e4 LT |
495 | return; |
496 | ||
497 | /* | |
498 | * Construct source address and options. | |
499 | */ | |
500 | ||
501 | saddr = iph->daddr; | |
1c2fb7f9 | 502 | if (!(rt->rt_flags & RTCF_LOCAL)) { |
6e1d9103 PM |
503 | struct net_device *dev = NULL; |
504 | ||
685c7944 | 505 | rcu_read_lock(); |
a24022e1 | 506 | if (rt->fl.iif && |
b34a95ee | 507 | net->ipv4.sysctl_icmp_errors_use_inbound_ifaddr) |
685c7944 | 508 | dev = dev_get_by_index_rcu(net, rt->fl.iif); |
6e1d9103 | 509 | |
685c7944 | 510 | if (dev) |
6e1d9103 | 511 | saddr = inet_select_addr(dev, 0, RT_SCOPE_LINK); |
685c7944 | 512 | else |
1c2fb7f9 | 513 | saddr = 0; |
685c7944 | 514 | rcu_read_unlock(); |
1c2fb7f9 | 515 | } |
1da177e4 LT |
516 | |
517 | tos = icmp_pointers[type].error ? ((iph->tos & IPTOS_TOS_MASK) | | |
518 | IPTOS_PREC_INTERNETCONTROL) : | |
519 | iph->tos; | |
520 | ||
521 | if (ip_options_echo(&icmp_param.replyopts, skb_in)) | |
fa60cf7f | 522 | goto out_unlock; |
1da177e4 LT |
523 | |
524 | ||
525 | /* | |
526 | * Prepare data for ICMP header. | |
527 | */ | |
528 | ||
529 | icmp_param.data.icmph.type = type; | |
530 | icmp_param.data.icmph.code = code; | |
531 | icmp_param.data.icmph.un.gateway = info; | |
532 | icmp_param.data.icmph.checksum = 0; | |
533 | icmp_param.skb = skb_in; | |
d56f90a7 | 534 | icmp_param.offset = skb_network_offset(skb_in); |
405666db | 535 | inet_sk(sk)->tos = tos; |
1da177e4 LT |
536 | ipc.addr = iph->saddr; |
537 | ipc.opt = &icmp_param.replyopts; | |
51f31cab | 538 | ipc.shtx.flags = 0; |
1da177e4 LT |
539 | |
540 | { | |
541 | struct flowi fl = { | |
542 | .nl_u = { | |
543 | .ip4_u = { | |
544 | .daddr = icmp_param.replyopts.srr ? | |
545 | icmp_param.replyopts.faddr : | |
546 | iph->saddr, | |
547 | .saddr = saddr, | |
548 | .tos = RT_TOS(tos) | |
549 | } | |
550 | }, | |
551 | .proto = IPPROTO_ICMP, | |
552 | .uli_u = { | |
553 | .icmpt = { | |
554 | .type = type, | |
555 | .code = code | |
556 | } | |
557 | } | |
558 | }; | |
8b7817f3 HX |
559 | int err; |
560 | struct rtable *rt2; | |
561 | ||
beb8d13b | 562 | security_skb_classify_flow(skb_in, &fl); |
dde1bc0e | 563 | if (__ip_route_output_key(net, &rt, &fl)) |
8b7817f3 HX |
564 | goto out_unlock; |
565 | ||
566 | /* No need to clone since we're just using its address. */ | |
567 | rt2 = rt; | |
568 | ||
52479b62 | 569 | err = xfrm_lookup(net, (struct dst_entry **)&rt, &fl, NULL, 0); |
8b7817f3 HX |
570 | switch (err) { |
571 | case 0: | |
572 | if (rt != rt2) | |
573 | goto route_done; | |
574 | break; | |
575 | case -EPERM: | |
576 | rt = NULL; | |
577 | break; | |
578 | default: | |
579 | goto out_unlock; | |
580 | } | |
581 | ||
582 | if (xfrm_decode_session_reverse(skb_in, &fl, AF_INET)) | |
af268182 | 583 | goto relookup_failed; |
8b7817f3 | 584 | |
dde1bc0e DL |
585 | if (inet_addr_type(net, fl.fl4_src) == RTN_LOCAL) |
586 | err = __ip_route_output_key(net, &rt2, &fl); | |
8b7817f3 HX |
587 | else { |
588 | struct flowi fl2 = {}; | |
589 | struct dst_entry *odst; | |
590 | ||
591 | fl2.fl4_dst = fl.fl4_src; | |
dde1bc0e | 592 | if (ip_route_output_key(net, &rt2, &fl2)) |
af268182 | 593 | goto relookup_failed; |
8b7817f3 HX |
594 | |
595 | /* Ugh! */ | |
adf30907 | 596 | odst = skb_dst(skb_in); |
8b7817f3 HX |
597 | err = ip_route_input(skb_in, fl.fl4_dst, fl.fl4_src, |
598 | RT_TOS(tos), rt2->u.dst.dev); | |
599 | ||
600 | dst_release(&rt2->u.dst); | |
511c3f92 | 601 | rt2 = skb_rtable(skb_in); |
adf30907 | 602 | skb_dst_set(skb_in, odst); |
8b7817f3 HX |
603 | } |
604 | ||
605 | if (err) | |
af268182 | 606 | goto relookup_failed; |
8b7817f3 | 607 | |
52479b62 | 608 | err = xfrm_lookup(net, (struct dst_entry **)&rt2, &fl, NULL, |
8b7817f3 | 609 | XFRM_LOOKUP_ICMP); |
af268182 HX |
610 | switch (err) { |
611 | case 0: | |
612 | dst_release(&rt->u.dst); | |
613 | rt = rt2; | |
614 | break; | |
615 | case -EPERM: | |
616 | goto ende; | |
617 | default: | |
618 | relookup_failed: | |
8b7817f3 HX |
619 | if (!rt) |
620 | goto out_unlock; | |
af268182 | 621 | break; |
8b7817f3 | 622 | } |
1da177e4 LT |
623 | } |
624 | ||
8b7817f3 | 625 | route_done: |
b34a95ee | 626 | if (!icmpv4_xrlim_allow(net, rt, type, code)) |
1da177e4 LT |
627 | goto ende; |
628 | ||
629 | /* RFC says return as much as we can without exceeding 576 bytes. */ | |
630 | ||
631 | room = dst_mtu(&rt->u.dst); | |
632 | if (room > 576) | |
633 | room = 576; | |
634 | room -= sizeof(struct iphdr) + icmp_param.replyopts.optlen; | |
635 | room -= sizeof(struct icmphdr); | |
636 | ||
637 | icmp_param.data_len = skb_in->len - icmp_param.offset; | |
638 | if (icmp_param.data_len > room) | |
639 | icmp_param.data_len = room; | |
640 | icmp_param.head_len = sizeof(struct icmphdr); | |
641 | ||
2e77d89b | 642 | icmp_push_reply(&icmp_param, &ipc, &rt); |
1da177e4 LT |
643 | ende: |
644 | ip_rt_put(rt); | |
645 | out_unlock: | |
405666db | 646 | icmp_xmit_unlock(sk); |
1da177e4 LT |
647 | out:; |
648 | } | |
649 | ||
650 | ||
651 | /* | |
652 | * Handle ICMP_DEST_UNREACH, ICMP_TIME_EXCEED, and ICMP_QUENCH. | |
653 | */ | |
654 | ||
655 | static void icmp_unreach(struct sk_buff *skb) | |
656 | { | |
657 | struct iphdr *iph; | |
658 | struct icmphdr *icmph; | |
659 | int hash, protocol; | |
32613090 | 660 | const struct net_protocol *ipprot; |
1da177e4 | 661 | u32 info = 0; |
dde1bc0e DL |
662 | struct net *net; |
663 | ||
adf30907 | 664 | net = dev_net(skb_dst(skb)->dev); |
1da177e4 LT |
665 | |
666 | /* | |
667 | * Incomplete header ? | |
668 | * Only checks for the IP header, there should be an | |
669 | * additional check for longer headers in upper levels. | |
670 | */ | |
671 | ||
672 | if (!pskb_may_pull(skb, sizeof(struct iphdr))) | |
673 | goto out_err; | |
674 | ||
88c7664f | 675 | icmph = icmp_hdr(skb); |
1da177e4 LT |
676 | iph = (struct iphdr *)skb->data; |
677 | ||
678 | if (iph->ihl < 5) /* Mangled header, drop. */ | |
679 | goto out_err; | |
680 | ||
681 | if (icmph->type == ICMP_DEST_UNREACH) { | |
682 | switch (icmph->code & 15) { | |
683 | case ICMP_NET_UNREACH: | |
684 | case ICMP_HOST_UNREACH: | |
685 | case ICMP_PROT_UNREACH: | |
686 | case ICMP_PORT_UNREACH: | |
687 | break; | |
688 | case ICMP_FRAG_NEEDED: | |
689 | if (ipv4_config.no_pmtu_disc) { | |
673d57e7 HH |
690 | LIMIT_NETDEBUG(KERN_INFO "ICMP: %pI4: fragmentation needed and DF set.\n", |
691 | &iph->daddr); | |
1da177e4 | 692 | } else { |
dde1bc0e | 693 | info = ip_rt_frag_needed(net, iph, |
0010e465 TT |
694 | ntohs(icmph->un.frag.mtu), |
695 | skb->dev); | |
1da177e4 LT |
696 | if (!info) |
697 | goto out; | |
698 | } | |
699 | break; | |
700 | case ICMP_SR_FAILED: | |
673d57e7 HH |
701 | LIMIT_NETDEBUG(KERN_INFO "ICMP: %pI4: Source Route Failed.\n", |
702 | &iph->daddr); | |
1da177e4 LT |
703 | break; |
704 | default: | |
705 | break; | |
706 | } | |
707 | if (icmph->code > NR_ICMP_UNREACH) | |
708 | goto out; | |
709 | } else if (icmph->type == ICMP_PARAMETERPROB) | |
710 | info = ntohl(icmph->un.gateway) >> 24; | |
711 | ||
712 | /* | |
713 | * Throw it at our lower layers | |
714 | * | |
715 | * RFC 1122: 3.2.2 MUST extract the protocol ID from the passed | |
716 | * header. | |
717 | * RFC 1122: 3.2.2.1 MUST pass ICMP unreach messages to the | |
718 | * transport layer. | |
719 | * RFC 1122: 3.2.2.2 MUST pass ICMP time expired messages to | |
720 | * transport layer. | |
721 | */ | |
722 | ||
723 | /* | |
724 | * Check the other end isnt violating RFC 1122. Some routers send | |
725 | * bogus responses to broadcast frames. If you see this message | |
726 | * first check your netmask matches at both ends, if it does then | |
727 | * get the other vendor to fix their kit. | |
728 | */ | |
729 | ||
b34a95ee | 730 | if (!net->ipv4.sysctl_icmp_ignore_bogus_error_responses && |
dde1bc0e | 731 | inet_addr_type(net, iph->daddr) == RTN_BROADCAST) { |
1da177e4 | 732 | if (net_ratelimit()) |
673d57e7 | 733 | printk(KERN_WARNING "%pI4 sent an invalid ICMP " |
1da177e4 | 734 | "type %u, code %u " |
673d57e7 HH |
735 | "error to a broadcast: %pI4 on %s\n", |
736 | &ip_hdr(skb)->saddr, | |
1da177e4 | 737 | icmph->type, icmph->code, |
673d57e7 | 738 | &iph->daddr, |
1da177e4 LT |
739 | skb->dev->name); |
740 | goto out; | |
741 | } | |
742 | ||
743 | /* Checkin full IP header plus 8 bytes of protocol to | |
744 | * avoid additional coding at protocol handlers. | |
745 | */ | |
746 | if (!pskb_may_pull(skb, iph->ihl * 4 + 8)) | |
747 | goto out; | |
748 | ||
749 | iph = (struct iphdr *)skb->data; | |
750 | protocol = iph->protocol; | |
751 | ||
752 | /* | |
753 | * Deliver ICMP message to raw sockets. Pretty useless feature? | |
754 | */ | |
7bc54c90 | 755 | raw_icmp_error(skb, protocol, info); |
1da177e4 | 756 | |
1da177e4 | 757 | hash = protocol & (MAX_INET_PROTOS - 1); |
1da177e4 LT |
758 | rcu_read_lock(); |
759 | ipprot = rcu_dereference(inet_protos[hash]); | |
760 | if (ipprot && ipprot->err_handler) | |
761 | ipprot->err_handler(skb, info); | |
762 | rcu_read_unlock(); | |
763 | ||
764 | out: | |
765 | return; | |
766 | out_err: | |
dcfc23ca | 767 | ICMP_INC_STATS_BH(net, ICMP_MIB_INERRORS); |
1da177e4 LT |
768 | goto out; |
769 | } | |
770 | ||
771 | ||
772 | /* | |
773 | * Handle ICMP_REDIRECT. | |
774 | */ | |
775 | ||
776 | static void icmp_redirect(struct sk_buff *skb) | |
777 | { | |
778 | struct iphdr *iph; | |
1da177e4 LT |
779 | |
780 | if (skb->len < sizeof(struct iphdr)) | |
781 | goto out_err; | |
782 | ||
783 | /* | |
784 | * Get the copied header of the packet that caused the redirect | |
785 | */ | |
786 | if (!pskb_may_pull(skb, sizeof(struct iphdr))) | |
787 | goto out; | |
788 | ||
789 | iph = (struct iphdr *)skb->data; | |
1da177e4 | 790 | |
88c7664f | 791 | switch (icmp_hdr(skb)->code & 7) { |
1da177e4 LT |
792 | case ICMP_REDIR_NET: |
793 | case ICMP_REDIR_NETTOS: | |
794 | /* | |
795 | * As per RFC recommendations now handle it as a host redirect. | |
796 | */ | |
797 | case ICMP_REDIR_HOST: | |
798 | case ICMP_REDIR_HOSTTOS: | |
eddc9ec5 | 799 | ip_rt_redirect(ip_hdr(skb)->saddr, iph->daddr, |
88c7664f | 800 | icmp_hdr(skb)->un.gateway, |
cef2685e | 801 | iph->saddr, skb->dev); |
1da177e4 | 802 | break; |
e905a9ed | 803 | } |
1da177e4 LT |
804 | out: |
805 | return; | |
806 | out_err: | |
dcfc23ca | 807 | ICMP_INC_STATS_BH(dev_net(skb->dev), ICMP_MIB_INERRORS); |
1da177e4 LT |
808 | goto out; |
809 | } | |
810 | ||
811 | /* | |
812 | * Handle ICMP_ECHO ("ping") requests. | |
813 | * | |
814 | * RFC 1122: 3.2.2.6 MUST have an echo server that answers ICMP echo | |
815 | * requests. | |
816 | * RFC 1122: 3.2.2.6 Data received in the ICMP_ECHO request MUST be | |
817 | * included in the reply. | |
818 | * RFC 1812: 4.3.3.6 SHOULD have a config option for silently ignoring | |
819 | * echo requests, MUST have default=NOT. | |
820 | * See also WRT handling of options once they are done and working. | |
821 | */ | |
822 | ||
823 | static void icmp_echo(struct sk_buff *skb) | |
824 | { | |
b34a95ee PE |
825 | struct net *net; |
826 | ||
adf30907 | 827 | net = dev_net(skb_dst(skb)->dev); |
b34a95ee | 828 | if (!net->ipv4.sysctl_icmp_echo_ignore_all) { |
1da177e4 LT |
829 | struct icmp_bxm icmp_param; |
830 | ||
88c7664f | 831 | icmp_param.data.icmph = *icmp_hdr(skb); |
1da177e4 LT |
832 | icmp_param.data.icmph.type = ICMP_ECHOREPLY; |
833 | icmp_param.skb = skb; | |
834 | icmp_param.offset = 0; | |
835 | icmp_param.data_len = skb->len; | |
836 | icmp_param.head_len = sizeof(struct icmphdr); | |
837 | icmp_reply(&icmp_param, skb); | |
838 | } | |
839 | } | |
840 | ||
841 | /* | |
842 | * Handle ICMP Timestamp requests. | |
843 | * RFC 1122: 3.2.2.8 MAY implement ICMP timestamp requests. | |
844 | * SHOULD be in the kernel for minimum random latency. | |
845 | * MUST be accurate to a few minutes. | |
846 | * MUST be updated at least at 15Hz. | |
847 | */ | |
848 | static void icmp_timestamp(struct sk_buff *skb) | |
849 | { | |
f25c3d61 | 850 | struct timespec tv; |
1da177e4 LT |
851 | struct icmp_bxm icmp_param; |
852 | /* | |
853 | * Too short. | |
854 | */ | |
855 | if (skb->len < 4) | |
856 | goto out_err; | |
857 | ||
858 | /* | |
859 | * Fill in the current time as ms since midnight UT: | |
860 | */ | |
f25c3d61 YH |
861 | getnstimeofday(&tv); |
862 | icmp_param.data.times[1] = htonl((tv.tv_sec % 86400) * MSEC_PER_SEC + | |
863 | tv.tv_nsec / NSEC_PER_MSEC); | |
1da177e4 LT |
864 | icmp_param.data.times[2] = icmp_param.data.times[1]; |
865 | if (skb_copy_bits(skb, 0, &icmp_param.data.times[0], 4)) | |
866 | BUG(); | |
88c7664f | 867 | icmp_param.data.icmph = *icmp_hdr(skb); |
1da177e4 LT |
868 | icmp_param.data.icmph.type = ICMP_TIMESTAMPREPLY; |
869 | icmp_param.data.icmph.code = 0; | |
870 | icmp_param.skb = skb; | |
871 | icmp_param.offset = 0; | |
872 | icmp_param.data_len = 0; | |
873 | icmp_param.head_len = sizeof(struct icmphdr) + 12; | |
874 | icmp_reply(&icmp_param, skb); | |
875 | out: | |
876 | return; | |
877 | out_err: | |
adf30907 | 878 | ICMP_INC_STATS_BH(dev_net(skb_dst(skb)->dev), ICMP_MIB_INERRORS); |
1da177e4 LT |
879 | goto out; |
880 | } | |
881 | ||
882 | ||
883 | /* | |
884 | * Handle ICMP_ADDRESS_MASK requests. (RFC950) | |
885 | * | |
886 | * RFC1122 (3.2.2.9). A host MUST only send replies to | |
887 | * ADDRESS_MASK requests if it's been configured as an address mask | |
888 | * agent. Receiving a request doesn't constitute implicit permission to | |
889 | * act as one. Of course, implementing this correctly requires (SHOULD) | |
890 | * a way to turn the functionality on and off. Another one for sysctl(), | |
891 | * I guess. -- MS | |
892 | * | |
893 | * RFC1812 (4.3.3.9). A router MUST implement it. | |
894 | * A router SHOULD have switch turning it on/off. | |
895 | * This switch MUST be ON by default. | |
896 | * | |
897 | * Gratuitous replies, zero-source replies are not implemented, | |
898 | * that complies with RFC. DO NOT implement them!!! All the idea | |
899 | * of broadcast addrmask replies as specified in RFC950 is broken. | |
900 | * The problem is that it is not uncommon to have several prefixes | |
901 | * on one physical interface. Moreover, addrmask agent can even be | |
902 | * not aware of existing another prefixes. | |
903 | * If source is zero, addrmask agent cannot choose correct prefix. | |
904 | * Gratuitous mask announcements suffer from the same problem. | |
905 | * RFC1812 explains it, but still allows to use ADDRMASK, | |
906 | * that is pretty silly. --ANK | |
907 | * | |
908 | * All these rules are so bizarre, that I removed kernel addrmask | |
909 | * support at all. It is wrong, it is obsolete, nobody uses it in | |
910 | * any case. --ANK | |
911 | * | |
912 | * Furthermore you can do it with a usermode address agent program | |
913 | * anyway... | |
914 | */ | |
915 | ||
916 | static void icmp_address(struct sk_buff *skb) | |
917 | { | |
918 | #if 0 | |
919 | if (net_ratelimit()) | |
920 | printk(KERN_DEBUG "a guy asks for address mask. Who is it?\n"); | |
921 | #endif | |
922 | } | |
923 | ||
924 | /* | |
925 | * RFC1812 (4.3.3.9). A router SHOULD listen all replies, and complain | |
926 | * loudly if an inconsistency is found. | |
927 | */ | |
928 | ||
929 | static void icmp_address_reply(struct sk_buff *skb) | |
930 | { | |
511c3f92 | 931 | struct rtable *rt = skb_rtable(skb); |
1da177e4 LT |
932 | struct net_device *dev = skb->dev; |
933 | struct in_device *in_dev; | |
934 | struct in_ifaddr *ifa; | |
935 | ||
936 | if (skb->len < 4 || !(rt->rt_flags&RTCF_DIRECTSRC)) | |
937 | goto out; | |
938 | ||
939 | in_dev = in_dev_get(dev); | |
940 | if (!in_dev) | |
941 | goto out; | |
942 | rcu_read_lock(); | |
943 | if (in_dev->ifa_list && | |
944 | IN_DEV_LOG_MARTIANS(in_dev) && | |
945 | IN_DEV_FORWARD(in_dev)) { | |
a144ea4b | 946 | __be32 _mask, *mp; |
1da177e4 LT |
947 | |
948 | mp = skb_header_pointer(skb, 0, sizeof(_mask), &_mask); | |
09a62660 | 949 | BUG_ON(mp == NULL); |
1da177e4 LT |
950 | for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) { |
951 | if (*mp == ifa->ifa_mask && | |
952 | inet_ifa_match(rt->rt_src, ifa)) | |
953 | break; | |
954 | } | |
955 | if (!ifa && net_ratelimit()) { | |
673d57e7 HH |
956 | printk(KERN_INFO "Wrong address mask %pI4 from %s/%pI4\n", |
957 | mp, dev->name, &rt->rt_src); | |
1da177e4 LT |
958 | } |
959 | } | |
960 | rcu_read_unlock(); | |
961 | in_dev_put(in_dev); | |
962 | out:; | |
963 | } | |
964 | ||
965 | static void icmp_discard(struct sk_buff *skb) | |
966 | { | |
967 | } | |
968 | ||
969 | /* | |
970 | * Deal with incoming ICMP packets. | |
971 | */ | |
972 | int icmp_rcv(struct sk_buff *skb) | |
973 | { | |
974 | struct icmphdr *icmph; | |
511c3f92 | 975 | struct rtable *rt = skb_rtable(skb); |
fd54d716 | 976 | struct net *net = dev_net(rt->u.dst.dev); |
1da177e4 | 977 | |
aebcf82c | 978 | if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb)) { |
def8b4fa | 979 | struct sec_path *sp = skb_sec_path(skb); |
8b7817f3 HX |
980 | int nh; |
981 | ||
def8b4fa | 982 | if (!(sp && sp->xvec[sp->len - 1]->props.flags & |
aebcf82c HX |
983 | XFRM_STATE_ICMP)) |
984 | goto drop; | |
985 | ||
8b7817f3 HX |
986 | if (!pskb_may_pull(skb, sizeof(*icmph) + sizeof(struct iphdr))) |
987 | goto drop; | |
988 | ||
989 | nh = skb_network_offset(skb); | |
990 | skb_set_network_header(skb, sizeof(*icmph)); | |
991 | ||
992 | if (!xfrm4_policy_check_reverse(NULL, XFRM_POLICY_IN, skb)) | |
993 | goto drop; | |
994 | ||
995 | skb_set_network_header(skb, nh); | |
996 | } | |
997 | ||
dcfc23ca | 998 | ICMP_INC_STATS_BH(net, ICMP_MIB_INMSGS); |
1da177e4 LT |
999 | |
1000 | switch (skb->ip_summed) { | |
84fa7933 | 1001 | case CHECKSUM_COMPLETE: |
d3bc23e7 | 1002 | if (!csum_fold(skb->csum)) |
1da177e4 | 1003 | break; |
fb286bb2 | 1004 | /* fall through */ |
1da177e4 | 1005 | case CHECKSUM_NONE: |
fb286bb2 HX |
1006 | skb->csum = 0; |
1007 | if (__skb_checksum_complete(skb)) | |
1da177e4 | 1008 | goto error; |
1da177e4 LT |
1009 | } |
1010 | ||
8cf22943 HX |
1011 | if (!pskb_pull(skb, sizeof(*icmph))) |
1012 | goto error; | |
1da177e4 | 1013 | |
88c7664f | 1014 | icmph = icmp_hdr(skb); |
1da177e4 | 1015 | |
f66ac03d | 1016 | ICMPMSGIN_INC_STATS_BH(net, icmph->type); |
1da177e4 LT |
1017 | /* |
1018 | * 18 is the highest 'known' ICMP type. Anything else is a mystery | |
1019 | * | |
1020 | * RFC 1122: 3.2.2 Unknown ICMP messages types MUST be silently | |
1021 | * discarded. | |
1022 | */ | |
1023 | if (icmph->type > NR_ICMP_TYPES) | |
1024 | goto error; | |
1025 | ||
1026 | ||
1027 | /* | |
1028 | * Parse the ICMP message | |
1029 | */ | |
1030 | ||
e905a9ed | 1031 | if (rt->rt_flags & (RTCF_BROADCAST | RTCF_MULTICAST)) { |
1da177e4 LT |
1032 | /* |
1033 | * RFC 1122: 3.2.2.6 An ICMP_ECHO to broadcast MAY be | |
1034 | * silently ignored (we let user decide with a sysctl). | |
1035 | * RFC 1122: 3.2.2.8 An ICMP_TIMESTAMP MAY be silently | |
1036 | * discarded if to broadcast/multicast. | |
1037 | */ | |
4c866aa7 AK |
1038 | if ((icmph->type == ICMP_ECHO || |
1039 | icmph->type == ICMP_TIMESTAMP) && | |
b34a95ee | 1040 | net->ipv4.sysctl_icmp_echo_ignore_broadcasts) { |
1da177e4 LT |
1041 | goto error; |
1042 | } | |
1043 | if (icmph->type != ICMP_ECHO && | |
1044 | icmph->type != ICMP_TIMESTAMP && | |
1045 | icmph->type != ICMP_ADDRESS && | |
1046 | icmph->type != ICMP_ADDRESSREPLY) { | |
1047 | goto error; | |
e905a9ed | 1048 | } |
1da177e4 LT |
1049 | } |
1050 | ||
1da177e4 LT |
1051 | icmp_pointers[icmph->type].handler(skb); |
1052 | ||
1053 | drop: | |
1054 | kfree_skb(skb); | |
1055 | return 0; | |
1056 | error: | |
dcfc23ca | 1057 | ICMP_INC_STATS_BH(net, ICMP_MIB_INERRORS); |
1da177e4 LT |
1058 | goto drop; |
1059 | } | |
1060 | ||
1061 | /* | |
1062 | * This table is the definition of how we handle ICMP. | |
1063 | */ | |
9b5b5cff | 1064 | static const struct icmp_control icmp_pointers[NR_ICMP_TYPES + 1] = { |
1da177e4 | 1065 | [ICMP_ECHOREPLY] = { |
1da177e4 LT |
1066 | .handler = icmp_discard, |
1067 | }, | |
1068 | [1] = { | |
1da177e4 LT |
1069 | .handler = icmp_discard, |
1070 | .error = 1, | |
1071 | }, | |
1072 | [2] = { | |
1da177e4 LT |
1073 | .handler = icmp_discard, |
1074 | .error = 1, | |
1075 | }, | |
1076 | [ICMP_DEST_UNREACH] = { | |
1da177e4 LT |
1077 | .handler = icmp_unreach, |
1078 | .error = 1, | |
1079 | }, | |
1080 | [ICMP_SOURCE_QUENCH] = { | |
1da177e4 LT |
1081 | .handler = icmp_unreach, |
1082 | .error = 1, | |
1083 | }, | |
1084 | [ICMP_REDIRECT] = { | |
1da177e4 LT |
1085 | .handler = icmp_redirect, |
1086 | .error = 1, | |
1087 | }, | |
1088 | [6] = { | |
1da177e4 LT |
1089 | .handler = icmp_discard, |
1090 | .error = 1, | |
1091 | }, | |
1092 | [7] = { | |
1da177e4 LT |
1093 | .handler = icmp_discard, |
1094 | .error = 1, | |
1095 | }, | |
1096 | [ICMP_ECHO] = { | |
1da177e4 LT |
1097 | .handler = icmp_echo, |
1098 | }, | |
1099 | [9] = { | |
1da177e4 LT |
1100 | .handler = icmp_discard, |
1101 | .error = 1, | |
1102 | }, | |
1103 | [10] = { | |
1da177e4 LT |
1104 | .handler = icmp_discard, |
1105 | .error = 1, | |
1106 | }, | |
1107 | [ICMP_TIME_EXCEEDED] = { | |
1da177e4 LT |
1108 | .handler = icmp_unreach, |
1109 | .error = 1, | |
1110 | }, | |
1111 | [ICMP_PARAMETERPROB] = { | |
1da177e4 LT |
1112 | .handler = icmp_unreach, |
1113 | .error = 1, | |
1114 | }, | |
1115 | [ICMP_TIMESTAMP] = { | |
1da177e4 LT |
1116 | .handler = icmp_timestamp, |
1117 | }, | |
1118 | [ICMP_TIMESTAMPREPLY] = { | |
1da177e4 LT |
1119 | .handler = icmp_discard, |
1120 | }, | |
1121 | [ICMP_INFO_REQUEST] = { | |
1da177e4 LT |
1122 | .handler = icmp_discard, |
1123 | }, | |
e905a9ed | 1124 | [ICMP_INFO_REPLY] = { |
1da177e4 LT |
1125 | .handler = icmp_discard, |
1126 | }, | |
1127 | [ICMP_ADDRESS] = { | |
1da177e4 LT |
1128 | .handler = icmp_address, |
1129 | }, | |
1130 | [ICMP_ADDRESSREPLY] = { | |
1da177e4 LT |
1131 | .handler = icmp_address_reply, |
1132 | }, | |
1133 | }; | |
1134 | ||
4a6ad7a1 | 1135 | static void __net_exit icmp_sk_exit(struct net *net) |
1da177e4 | 1136 | { |
1da177e4 LT |
1137 | int i; |
1138 | ||
5c8cafd6 | 1139 | for_each_possible_cpu(i) |
c1e9894d | 1140 | inet_ctl_sock_destroy(net->ipv4.icmp_sk[i]); |
4a6ad7a1 DL |
1141 | kfree(net->ipv4.icmp_sk); |
1142 | net->ipv4.icmp_sk = NULL; | |
a5710d65 | 1143 | } |
1da177e4 | 1144 | |
263173af | 1145 | static int __net_init icmp_sk_init(struct net *net) |
a5710d65 | 1146 | { |
a5710d65 DL |
1147 | int i, err; |
1148 | ||
4a6ad7a1 DL |
1149 | net->ipv4.icmp_sk = |
1150 | kzalloc(nr_cpu_ids * sizeof(struct sock *), GFP_KERNEL); | |
1151 | if (net->ipv4.icmp_sk == NULL) | |
79c91159 DL |
1152 | return -ENOMEM; |
1153 | ||
a5710d65 | 1154 | for_each_possible_cpu(i) { |
1e3cf683 | 1155 | struct sock *sk; |
1da177e4 | 1156 | |
c1e9894d DL |
1157 | err = inet_ctl_sock_create(&sk, PF_INET, |
1158 | SOCK_RAW, IPPROTO_ICMP, net); | |
1da177e4 | 1159 | if (err < 0) |
a5710d65 | 1160 | goto fail; |
1da177e4 | 1161 | |
c1e9894d | 1162 | net->ipv4.icmp_sk[i] = sk; |
1da177e4 LT |
1163 | |
1164 | /* Enough space for 2 64K ICMP packets, including | |
1165 | * sk_buff struct overhead. | |
1166 | */ | |
1e3cf683 | 1167 | sk->sk_sndbuf = |
1da177e4 LT |
1168 | (2 * ((64 * 1024) + sizeof(struct sk_buff))); |
1169 | ||
b3a5b6cc ED |
1170 | /* |
1171 | * Speedup sock_wfree() | |
1172 | */ | |
1173 | sock_set_flag(sk, SOCK_USE_WRITE_QUEUE); | |
c1e9894d | 1174 | inet_sk(sk)->pmtudisc = IP_PMTUDISC_DONT; |
1da177e4 | 1175 | } |
a24022e1 PE |
1176 | |
1177 | /* Control parameters for ECHO replies. */ | |
1178 | net->ipv4.sysctl_icmp_echo_ignore_all = 0; | |
1179 | net->ipv4.sysctl_icmp_echo_ignore_broadcasts = 1; | |
1180 | ||
1181 | /* Control parameter - ignore bogus broadcast responses? */ | |
1182 | net->ipv4.sysctl_icmp_ignore_bogus_error_responses = 1; | |
1183 | ||
1184 | /* | |
1185 | * Configurable global rate limit. | |
1186 | * | |
1187 | * ratelimit defines tokens/packet consumed for dst->rate_token | |
1188 | * bucket ratemask defines which icmp types are ratelimited by | |
1189 | * setting it's bit position. | |
1190 | * | |
1191 | * default: | |
1192 | * dest unreachable (3), source quench (4), | |
1193 | * time exceeded (11), parameter problem (12) | |
1194 | */ | |
1195 | ||
1196 | net->ipv4.sysctl_icmp_ratelimit = 1 * HZ; | |
1197 | net->ipv4.sysctl_icmp_ratemask = 0x1818; | |
1198 | net->ipv4.sysctl_icmp_errors_use_inbound_ifaddr = 0; | |
1199 | ||
a5710d65 DL |
1200 | return 0; |
1201 | ||
1202 | fail: | |
1d1c8d13 | 1203 | for_each_possible_cpu(i) |
c1e9894d | 1204 | inet_ctl_sock_destroy(net->ipv4.icmp_sk[i]); |
1d1c8d13 | 1205 | kfree(net->ipv4.icmp_sk); |
a5710d65 | 1206 | return err; |
1da177e4 LT |
1207 | } |
1208 | ||
4a6ad7a1 DL |
1209 | static struct pernet_operations __net_initdata icmp_sk_ops = { |
1210 | .init = icmp_sk_init, | |
1211 | .exit = icmp_sk_exit, | |
1212 | }; | |
1213 | ||
1214 | int __init icmp_init(void) | |
1215 | { | |
959d2726 | 1216 | return register_pernet_subsys(&icmp_sk_ops); |
4a6ad7a1 DL |
1217 | } |
1218 | ||
1da177e4 LT |
1219 | EXPORT_SYMBOL(icmp_err_convert); |
1220 | EXPORT_SYMBOL(icmp_send); | |
1da177e4 | 1221 | EXPORT_SYMBOL(xrlim_allow); |