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 | ||
afd46503 JP |
65 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
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> | |
5a0e3ad6 | 79 | #include <linux/slab.h> |
1da177e4 LT |
80 | #include <net/snmp.h> |
81 | #include <net/ip.h> | |
82 | #include <net/route.h> | |
83 | #include <net/protocol.h> | |
84 | #include <net/icmp.h> | |
85 | #include <net/tcp.h> | |
86 | #include <net/udp.h> | |
87 | #include <net/raw.h> | |
c319b4d7 | 88 | #include <net/ping.h> |
1da177e4 LT |
89 | #include <linux/skbuff.h> |
90 | #include <net/sock.h> | |
91 | #include <linux/errno.h> | |
92 | #include <linux/timer.h> | |
93 | #include <linux/init.h> | |
1da177e4 LT |
94 | #include <asm/uaccess.h> |
95 | #include <net/checksum.h> | |
8b7817f3 | 96 | #include <net/xfrm.h> |
c1e9894d | 97 | #include <net/inet_common.h> |
35ebf65e | 98 | #include <net/ip_fib.h> |
1da177e4 LT |
99 | |
100 | /* | |
101 | * Build xmit assembly blocks | |
102 | */ | |
103 | ||
104 | struct icmp_bxm { | |
105 | struct sk_buff *skb; | |
106 | int offset; | |
107 | int data_len; | |
108 | ||
109 | struct { | |
110 | struct icmphdr icmph; | |
b03d73e3 | 111 | __be32 times[3]; |
1da177e4 LT |
112 | } data; |
113 | int head_len; | |
f6d8bd05 | 114 | struct ip_options_data replyopts; |
1da177e4 LT |
115 | }; |
116 | ||
1da177e4 LT |
117 | /* An array of errno for error messages from dest unreach. */ |
118 | /* RFC 1122: 3.2.2.1 States that NET_UNREACH, HOST_UNREACH and SR_FAILED MUST be considered 'transient errs'. */ | |
119 | ||
e754834e | 120 | const struct icmp_err icmp_err_convert[] = { |
1da177e4 LT |
121 | { |
122 | .errno = ENETUNREACH, /* ICMP_NET_UNREACH */ | |
123 | .fatal = 0, | |
124 | }, | |
125 | { | |
126 | .errno = EHOSTUNREACH, /* ICMP_HOST_UNREACH */ | |
127 | .fatal = 0, | |
128 | }, | |
129 | { | |
130 | .errno = ENOPROTOOPT /* ICMP_PROT_UNREACH */, | |
131 | .fatal = 1, | |
132 | }, | |
133 | { | |
134 | .errno = ECONNREFUSED, /* ICMP_PORT_UNREACH */ | |
135 | .fatal = 1, | |
136 | }, | |
137 | { | |
138 | .errno = EMSGSIZE, /* ICMP_FRAG_NEEDED */ | |
139 | .fatal = 0, | |
140 | }, | |
141 | { | |
142 | .errno = EOPNOTSUPP, /* ICMP_SR_FAILED */ | |
143 | .fatal = 0, | |
144 | }, | |
145 | { | |
146 | .errno = ENETUNREACH, /* ICMP_NET_UNKNOWN */ | |
147 | .fatal = 1, | |
148 | }, | |
149 | { | |
150 | .errno = EHOSTDOWN, /* ICMP_HOST_UNKNOWN */ | |
151 | .fatal = 1, | |
152 | }, | |
153 | { | |
154 | .errno = ENONET, /* ICMP_HOST_ISOLATED */ | |
155 | .fatal = 1, | |
156 | }, | |
157 | { | |
158 | .errno = ENETUNREACH, /* ICMP_NET_ANO */ | |
159 | .fatal = 1, | |
160 | }, | |
161 | { | |
162 | .errno = EHOSTUNREACH, /* ICMP_HOST_ANO */ | |
163 | .fatal = 1, | |
164 | }, | |
165 | { | |
166 | .errno = ENETUNREACH, /* ICMP_NET_UNR_TOS */ | |
167 | .fatal = 0, | |
168 | }, | |
169 | { | |
170 | .errno = EHOSTUNREACH, /* ICMP_HOST_UNR_TOS */ | |
171 | .fatal = 0, | |
172 | }, | |
173 | { | |
174 | .errno = EHOSTUNREACH, /* ICMP_PKT_FILTERED */ | |
175 | .fatal = 1, | |
176 | }, | |
177 | { | |
178 | .errno = EHOSTUNREACH, /* ICMP_PREC_VIOLATION */ | |
179 | .fatal = 1, | |
180 | }, | |
181 | { | |
182 | .errno = EHOSTUNREACH, /* ICMP_PREC_CUTOFF */ | |
183 | .fatal = 1, | |
184 | }, | |
185 | }; | |
4bc2f18b | 186 | EXPORT_SYMBOL(icmp_err_convert); |
1da177e4 | 187 | |
1da177e4 LT |
188 | /* |
189 | * ICMP control array. This specifies what to do with each ICMP. | |
190 | */ | |
191 | ||
192 | struct icmp_control { | |
1da177e4 LT |
193 | void (*handler)(struct sk_buff *skb); |
194 | short error; /* This ICMP is classed as an error message */ | |
195 | }; | |
196 | ||
9b5b5cff | 197 | static const struct icmp_control icmp_pointers[NR_ICMP_TYPES+1]; |
1da177e4 LT |
198 | |
199 | /* | |
200 | * The ICMP socket(s). This is the most convenient way to flow control | |
201 | * our ICMP output as well as maintain a clean interface throughout | |
202 | * all layers. All Socketless IP sends will soon be gone. | |
203 | * | |
204 | * On SMP we have one ICMP socket per-cpu. | |
205 | */ | |
4a6ad7a1 DL |
206 | static struct sock *icmp_sk(struct net *net) |
207 | { | |
208 | return net->ipv4.icmp_sk[smp_processor_id()]; | |
209 | } | |
1da177e4 | 210 | |
fdc0bde9 | 211 | static inline struct sock *icmp_xmit_lock(struct net *net) |
1da177e4 | 212 | { |
fdc0bde9 DL |
213 | struct sock *sk; |
214 | ||
1da177e4 LT |
215 | local_bh_disable(); |
216 | ||
fdc0bde9 DL |
217 | sk = icmp_sk(net); |
218 | ||
405666db | 219 | if (unlikely(!spin_trylock(&sk->sk_lock.slock))) { |
1da177e4 LT |
220 | /* This can happen if the output path signals a |
221 | * dst_link_failure() for an outgoing ICMP packet. | |
222 | */ | |
223 | local_bh_enable(); | |
fdc0bde9 | 224 | return NULL; |
1da177e4 | 225 | } |
fdc0bde9 | 226 | return sk; |
1da177e4 LT |
227 | } |
228 | ||
405666db | 229 | static inline void icmp_xmit_unlock(struct sock *sk) |
1da177e4 | 230 | { |
405666db | 231 | spin_unlock_bh(&sk->sk_lock.slock); |
1da177e4 LT |
232 | } |
233 | ||
234 | /* | |
235 | * Send an ICMP frame. | |
236 | */ | |
237 | ||
92d86829 | 238 | static inline bool icmpv4_xrlim_allow(struct net *net, struct rtable *rt, |
a48eff12 | 239 | struct flowi4 *fl4, int type, int code) |
1da177e4 | 240 | { |
d8d1f30b | 241 | struct dst_entry *dst = &rt->dst; |
92d86829 | 242 | bool rc = true; |
1da177e4 LT |
243 | |
244 | if (type > NR_ICMP_TYPES) | |
245 | goto out; | |
246 | ||
247 | /* Don't limit PMTU discovery. */ | |
248 | if (type == ICMP_DEST_UNREACH && code == ICMP_FRAG_NEEDED) | |
249 | goto out; | |
250 | ||
251 | /* No rate limit on loopback */ | |
252 | if (dst->dev && (dst->dev->flags&IFF_LOOPBACK)) | |
e905a9ed | 253 | goto out; |
1da177e4 LT |
254 | |
255 | /* Limit if icmp type is enabled in ratemask. */ | |
92d86829 | 256 | if ((1 << type) & net->ipv4.sysctl_icmp_ratemask) { |
1d861aa4 | 257 | struct inet_peer *peer = inet_getpeer_v4(net->ipv4.peers, fl4->daddr, 1); |
fbfe95a4 | 258 | rc = inet_peer_xrlim_allow(peer, |
92d86829 | 259 | net->ipv4.sysctl_icmp_ratelimit); |
e1a67642 NC |
260 | if (peer) |
261 | inet_putpeer(peer); | |
92d86829 | 262 | } |
1da177e4 LT |
263 | out: |
264 | return rc; | |
265 | } | |
266 | ||
267 | /* | |
268 | * Maintain the counters used in the SNMP statistics for outgoing ICMP | |
269 | */ | |
0388b004 | 270 | void icmp_out_count(struct net *net, unsigned char type) |
1da177e4 | 271 | { |
903fc196 | 272 | ICMPMSGOUT_INC_STATS(net, type); |
75c939bb | 273 | ICMP_INC_STATS(net, ICMP_MIB_OUTMSGS); |
1da177e4 LT |
274 | } |
275 | ||
276 | /* | |
277 | * Checksum each fragment, and on the first include the headers and final | |
278 | * checksum. | |
279 | */ | |
280 | static int icmp_glue_bits(void *from, char *to, int offset, int len, int odd, | |
281 | struct sk_buff *skb) | |
282 | { | |
283 | struct icmp_bxm *icmp_param = (struct icmp_bxm *)from; | |
5f92a738 | 284 | __wsum csum; |
1da177e4 LT |
285 | |
286 | csum = skb_copy_and_csum_bits(icmp_param->skb, | |
287 | icmp_param->offset + offset, | |
288 | to, len, 0); | |
289 | ||
290 | skb->csum = csum_block_add(skb->csum, csum, odd); | |
291 | if (icmp_pointers[icmp_param->data.icmph.type].error) | |
292 | nf_ct_attach(skb, icmp_param->skb); | |
293 | return 0; | |
294 | } | |
295 | ||
296 | static void icmp_push_reply(struct icmp_bxm *icmp_param, | |
77968b78 | 297 | struct flowi4 *fl4, |
2e77d89b | 298 | struct ipcm_cookie *ipc, struct rtable **rt) |
1da177e4 | 299 | { |
1e3cf683 | 300 | struct sock *sk; |
1da177e4 LT |
301 | struct sk_buff *skb; |
302 | ||
d8d1f30b | 303 | sk = icmp_sk(dev_net((*rt)->dst.dev)); |
f5fca608 | 304 | if (ip_append_data(sk, fl4, icmp_glue_bits, icmp_param, |
e905a9ed YH |
305 | icmp_param->data_len+icmp_param->head_len, |
306 | icmp_param->head_len, | |
1f8438a8 ED |
307 | ipc, rt, MSG_DONTWAIT) < 0) { |
308 | ICMP_INC_STATS_BH(sock_net(sk), ICMP_MIB_OUTERRORS); | |
1e3cf683 | 309 | ip_flush_pending_frames(sk); |
1f8438a8 | 310 | } else if ((skb = skb_peek(&sk->sk_write_queue)) != NULL) { |
88c7664f | 311 | struct icmphdr *icmph = icmp_hdr(skb); |
d3bc23e7 | 312 | __wsum csum = 0; |
1da177e4 LT |
313 | struct sk_buff *skb1; |
314 | ||
1e3cf683 | 315 | skb_queue_walk(&sk->sk_write_queue, skb1) { |
1da177e4 LT |
316 | csum = csum_add(csum, skb1->csum); |
317 | } | |
318 | csum = csum_partial_copy_nocheck((void *)&icmp_param->data, | |
319 | (char *)icmph, | |
320 | icmp_param->head_len, csum); | |
321 | icmph->checksum = csum_fold(csum); | |
322 | skb->ip_summed = CHECKSUM_NONE; | |
77968b78 | 323 | ip_push_pending_frames(sk, fl4); |
1da177e4 LT |
324 | } |
325 | } | |
326 | ||
327 | /* | |
328 | * Driving logic for building and sending ICMP messages. | |
329 | */ | |
330 | ||
331 | static void icmp_reply(struct icmp_bxm *icmp_param, struct sk_buff *skb) | |
332 | { | |
1da177e4 | 333 | struct ipcm_cookie ipc; |
511c3f92 | 334 | struct rtable *rt = skb_rtable(skb); |
d8d1f30b | 335 | struct net *net = dev_net(rt->dst.dev); |
77968b78 | 336 | struct flowi4 fl4; |
fdc0bde9 DL |
337 | struct sock *sk; |
338 | struct inet_sock *inet; | |
35ebf65e | 339 | __be32 daddr, saddr; |
3c2a0909 | 340 | u32 mark = IP4_REPLY_MARK(net, skb->mark); |
1da177e4 | 341 | |
f6d8bd05 | 342 | if (ip_options_echo(&icmp_param->replyopts.opt.opt, skb)) |
f00c401b | 343 | return; |
1da177e4 | 344 | |
fdc0bde9 DL |
345 | sk = icmp_xmit_lock(net); |
346 | if (sk == NULL) | |
1da177e4 | 347 | return; |
fdc0bde9 | 348 | inet = inet_sk(sk); |
1da177e4 LT |
349 | |
350 | icmp_param->data.icmph.checksum = 0; | |
1da177e4 | 351 | |
eddc9ec5 | 352 | inet->tos = ip_hdr(skb)->tos; |
3c2a0909 | 353 | sk->sk_mark = mark; |
9f6abb5f | 354 | daddr = ipc.addr = ip_hdr(skb)->saddr; |
35ebf65e | 355 | saddr = fib_compute_spec_dst(skb); |
1da177e4 | 356 | ipc.opt = NULL; |
2244d07b | 357 | ipc.tx_flags = 0; |
f6d8bd05 ED |
358 | if (icmp_param->replyopts.opt.opt.optlen) { |
359 | ipc.opt = &icmp_param->replyopts.opt; | |
360 | if (ipc.opt->opt.srr) | |
361 | daddr = icmp_param->replyopts.opt.opt.faddr; | |
1da177e4 | 362 | } |
77968b78 DM |
363 | memset(&fl4, 0, sizeof(fl4)); |
364 | fl4.daddr = daddr; | |
35ebf65e | 365 | fl4.saddr = saddr; |
3c2a0909 | 366 | fl4.flowi4_mark = mark; |
83a2dfd5 | 367 | fl4.flowi4_uid = sock_net_uid(net, NULL); |
77968b78 DM |
368 | fl4.flowi4_tos = RT_TOS(ip_hdr(skb)->tos); |
369 | fl4.flowi4_proto = IPPROTO_ICMP; | |
370 | security_skb_classify_flow(skb, flowi4_to_flowi(&fl4)); | |
371 | rt = ip_route_output_key(net, &fl4); | |
372 | if (IS_ERR(rt)) | |
373 | goto out_unlock; | |
a48eff12 | 374 | if (icmpv4_xrlim_allow(net, rt, &fl4, icmp_param->data.icmph.type, |
1da177e4 | 375 | icmp_param->data.icmph.code)) |
77968b78 | 376 | icmp_push_reply(icmp_param, &fl4, &ipc, &rt); |
1da177e4 LT |
377 | ip_rt_put(rt); |
378 | out_unlock: | |
405666db | 379 | icmp_xmit_unlock(sk); |
1da177e4 LT |
380 | } |
381 | ||
77968b78 DM |
382 | static struct rtable *icmp_route_lookup(struct net *net, |
383 | struct flowi4 *fl4, | |
384 | struct sk_buff *skb_in, | |
b71d1d42 | 385 | const struct iphdr *iph, |
3c2a0909 | 386 | __be32 saddr, u8 tos, u32 mark, |
f6d460cf DM |
387 | int type, int code, |
388 | struct icmp_bxm *param) | |
389 | { | |
f6d460cf | 390 | struct rtable *rt, *rt2; |
415b3334 | 391 | struct flowi4 fl4_dec; |
f6d460cf DM |
392 | int err; |
393 | ||
77968b78 DM |
394 | memset(fl4, 0, sizeof(*fl4)); |
395 | fl4->daddr = (param->replyopts.opt.opt.srr ? | |
396 | param->replyopts.opt.opt.faddr : iph->saddr); | |
397 | fl4->saddr = saddr; | |
3c2a0909 | 398 | fl4->flowi4_mark = mark; |
83a2dfd5 | 399 | fl4->flowi4_uid = sock_net_uid(net, NULL); |
77968b78 DM |
400 | fl4->flowi4_tos = RT_TOS(tos); |
401 | fl4->flowi4_proto = IPPROTO_ICMP; | |
402 | fl4->fl4_icmp_type = type; | |
403 | fl4->fl4_icmp_code = code; | |
404 | security_skb_classify_flow(skb_in, flowi4_to_flowi(fl4)); | |
405 | rt = __ip_route_output_key(net, fl4); | |
b23dd4fe DM |
406 | if (IS_ERR(rt)) |
407 | return rt; | |
f6d460cf DM |
408 | |
409 | /* No need to clone since we're just using its address. */ | |
410 | rt2 = rt; | |
411 | ||
9d6ec938 | 412 | rt = (struct rtable *) xfrm_lookup(net, &rt->dst, |
77968b78 | 413 | flowi4_to_flowi(fl4), NULL, 0); |
452edd59 | 414 | if (!IS_ERR(rt)) { |
f6d460cf DM |
415 | if (rt != rt2) |
416 | return rt; | |
452edd59 | 417 | } else if (PTR_ERR(rt) == -EPERM) { |
f6d460cf | 418 | rt = NULL; |
452edd59 DM |
419 | } else |
420 | return rt; | |
f6d460cf | 421 | |
415b3334 | 422 | err = xfrm_decode_session_reverse(skb_in, flowi4_to_flowi(&fl4_dec), AF_INET); |
f6d460cf DM |
423 | if (err) |
424 | goto relookup_failed; | |
425 | ||
415b3334 DM |
426 | if (inet_addr_type(net, fl4_dec.saddr) == RTN_LOCAL) { |
427 | rt2 = __ip_route_output_key(net, &fl4_dec); | |
b23dd4fe DM |
428 | if (IS_ERR(rt2)) |
429 | err = PTR_ERR(rt2); | |
f6d460cf | 430 | } else { |
9d6ec938 | 431 | struct flowi4 fl4_2 = {}; |
f6d460cf DM |
432 | unsigned long orefdst; |
433 | ||
415b3334 | 434 | fl4_2.daddr = fl4_dec.saddr; |
9d6ec938 | 435 | rt2 = ip_route_output_key(net, &fl4_2); |
b23dd4fe DM |
436 | if (IS_ERR(rt2)) { |
437 | err = PTR_ERR(rt2); | |
f6d460cf | 438 | goto relookup_failed; |
b23dd4fe | 439 | } |
f6d460cf DM |
440 | /* Ugh! */ |
441 | orefdst = skb_in->_skb_refdst; /* save old refdst */ | |
415b3334 | 442 | err = ip_route_input(skb_in, fl4_dec.daddr, fl4_dec.saddr, |
f6d460cf DM |
443 | RT_TOS(tos), rt2->dst.dev); |
444 | ||
445 | dst_release(&rt2->dst); | |
446 | rt2 = skb_rtable(skb_in); | |
447 | skb_in->_skb_refdst = orefdst; /* restore old refdst */ | |
448 | } | |
449 | ||
450 | if (err) | |
451 | goto relookup_failed; | |
452 | ||
9d6ec938 | 453 | rt2 = (struct rtable *) xfrm_lookup(net, &rt2->dst, |
415b3334 | 454 | flowi4_to_flowi(&fl4_dec), NULL, |
9d6ec938 | 455 | XFRM_LOOKUP_ICMP); |
452edd59 | 456 | if (!IS_ERR(rt2)) { |
f6d460cf | 457 | dst_release(&rt->dst); |
415b3334 | 458 | memcpy(fl4, &fl4_dec, sizeof(*fl4)); |
f6d460cf | 459 | rt = rt2; |
452edd59 DM |
460 | } else if (PTR_ERR(rt2) == -EPERM) { |
461 | if (rt) | |
462 | dst_release(&rt->dst); | |
463 | return rt2; | |
464 | } else { | |
465 | err = PTR_ERR(rt2); | |
466 | goto relookup_failed; | |
f6d460cf | 467 | } |
f6d460cf DM |
468 | return rt; |
469 | ||
470 | relookup_failed: | |
471 | if (rt) | |
472 | return rt; | |
473 | return ERR_PTR(err); | |
474 | } | |
1da177e4 LT |
475 | |
476 | /* | |
477 | * Send an ICMP message in response to a situation | |
478 | * | |
479 | * RFC 1122: 3.2.2 MUST send at least the IP header and 8 bytes of header. | |
480 | * MAY send more (we do). | |
481 | * MUST NOT change this header information. | |
482 | * MUST NOT reply to a multicast/broadcast IP address. | |
483 | * MUST NOT reply to a multicast/broadcast MAC address. | |
484 | * MUST reply to only the first fragment. | |
485 | */ | |
486 | ||
e4883014 | 487 | void icmp_send(struct sk_buff *skb_in, int type, int code, __be32 info) |
1da177e4 LT |
488 | { |
489 | struct iphdr *iph; | |
490 | int room; | |
491 | struct icmp_bxm icmp_param; | |
511c3f92 | 492 | struct rtable *rt = skb_rtable(skb_in); |
1da177e4 | 493 | struct ipcm_cookie ipc; |
77968b78 | 494 | struct flowi4 fl4; |
a61ced5d | 495 | __be32 saddr; |
1da177e4 | 496 | u8 tos; |
3c2a0909 | 497 | u32 mark; |
dde1bc0e | 498 | struct net *net; |
4a6ad7a1 | 499 | struct sock *sk; |
1da177e4 LT |
500 | |
501 | if (!rt) | |
502 | goto out; | |
d8d1f30b | 503 | net = dev_net(rt->dst.dev); |
1da177e4 LT |
504 | |
505 | /* | |
506 | * Find the original header. It is expected to be valid, of course. | |
507 | * Check this, icmp_send is called from the most obscure devices | |
508 | * sometimes. | |
509 | */ | |
eddc9ec5 | 510 | iph = ip_hdr(skb_in); |
1da177e4 | 511 | |
27a884dc ACM |
512 | if ((u8 *)iph < skb_in->head || |
513 | (skb_in->network_header + sizeof(*iph)) > skb_in->tail) | |
1da177e4 LT |
514 | goto out; |
515 | ||
516 | /* | |
517 | * No replies to physical multicast/broadcast | |
518 | */ | |
519 | if (skb_in->pkt_type != PACKET_HOST) | |
520 | goto out; | |
521 | ||
522 | /* | |
523 | * Now check at the protocol level | |
524 | */ | |
525 | if (rt->rt_flags & (RTCF_BROADCAST | RTCF_MULTICAST)) | |
526 | goto out; | |
527 | ||
528 | /* | |
529 | * Only reply to fragment 0. We byte re-order the constant | |
530 | * mask for efficiency. | |
531 | */ | |
532 | if (iph->frag_off & htons(IP_OFFSET)) | |
533 | goto out; | |
534 | ||
535 | /* | |
536 | * If we send an ICMP error to an ICMP error a mess would result.. | |
537 | */ | |
538 | if (icmp_pointers[type].error) { | |
539 | /* | |
540 | * We are an error, check if we are replying to an | |
541 | * ICMP error | |
542 | */ | |
543 | if (iph->protocol == IPPROTO_ICMP) { | |
544 | u8 _inner_type, *itp; | |
545 | ||
546 | itp = skb_header_pointer(skb_in, | |
d56f90a7 | 547 | skb_network_header(skb_in) + |
1da177e4 LT |
548 | (iph->ihl << 2) + |
549 | offsetof(struct icmphdr, | |
550 | type) - | |
551 | skb_in->data, | |
552 | sizeof(_inner_type), | |
553 | &_inner_type); | |
554 | if (itp == NULL) | |
555 | goto out; | |
556 | ||
557 | /* | |
558 | * Assume any unknown ICMP type is an error. This | |
559 | * isn't specified by the RFC, but think about it.. | |
560 | */ | |
561 | if (*itp > NR_ICMP_TYPES || | |
562 | icmp_pointers[*itp].error) | |
563 | goto out; | |
564 | } | |
565 | } | |
566 | ||
fdc0bde9 DL |
567 | sk = icmp_xmit_lock(net); |
568 | if (sk == NULL) | |
1da177e4 LT |
569 | return; |
570 | ||
571 | /* | |
572 | * Construct source address and options. | |
573 | */ | |
574 | ||
575 | saddr = iph->daddr; | |
1c2fb7f9 | 576 | if (!(rt->rt_flags & RTCF_LOCAL)) { |
6e1d9103 PM |
577 | struct net_device *dev = NULL; |
578 | ||
685c7944 | 579 | rcu_read_lock(); |
c7537967 DM |
580 | if (rt_is_input_route(rt) && |
581 | net->ipv4.sysctl_icmp_errors_use_inbound_ifaddr) | |
92101b3b | 582 | dev = dev_get_by_index_rcu(net, inet_iif(skb_in)); |
6e1d9103 | 583 | |
685c7944 | 584 | if (dev) |
6e1d9103 | 585 | saddr = inet_select_addr(dev, 0, RT_SCOPE_LINK); |
685c7944 | 586 | else |
1c2fb7f9 | 587 | saddr = 0; |
685c7944 | 588 | rcu_read_unlock(); |
1c2fb7f9 | 589 | } |
1da177e4 LT |
590 | |
591 | tos = icmp_pointers[type].error ? ((iph->tos & IPTOS_TOS_MASK) | | |
592 | IPTOS_PREC_INTERNETCONTROL) : | |
593 | iph->tos; | |
3c2a0909 | 594 | mark = IP4_REPLY_MARK(net, skb_in->mark); |
1da177e4 | 595 | |
f6d8bd05 | 596 | if (ip_options_echo(&icmp_param.replyopts.opt.opt, skb_in)) |
fa60cf7f | 597 | goto out_unlock; |
1da177e4 LT |
598 | |
599 | ||
600 | /* | |
601 | * Prepare data for ICMP header. | |
602 | */ | |
603 | ||
604 | icmp_param.data.icmph.type = type; | |
605 | icmp_param.data.icmph.code = code; | |
606 | icmp_param.data.icmph.un.gateway = info; | |
607 | icmp_param.data.icmph.checksum = 0; | |
608 | icmp_param.skb = skb_in; | |
d56f90a7 | 609 | icmp_param.offset = skb_network_offset(skb_in); |
405666db | 610 | inet_sk(sk)->tos = tos; |
3c2a0909 | 611 | sk->sk_mark = mark; |
1da177e4 | 612 | ipc.addr = iph->saddr; |
f6d8bd05 | 613 | ipc.opt = &icmp_param.replyopts.opt; |
2244d07b | 614 | ipc.tx_flags = 0; |
1da177e4 | 615 | |
3c2a0909 | 616 | rt = icmp_route_lookup(net, &fl4, skb_in, iph, saddr, tos, mark, |
f6d460cf DM |
617 | type, code, &icmp_param); |
618 | if (IS_ERR(rt)) | |
619 | goto out_unlock; | |
1da177e4 | 620 | |
a48eff12 | 621 | if (!icmpv4_xrlim_allow(net, rt, &fl4, type, code)) |
1da177e4 LT |
622 | goto ende; |
623 | ||
624 | /* RFC says return as much as we can without exceeding 576 bytes. */ | |
625 | ||
d8d1f30b | 626 | room = dst_mtu(&rt->dst); |
1da177e4 LT |
627 | if (room > 576) |
628 | room = 576; | |
f6d8bd05 | 629 | room -= sizeof(struct iphdr) + icmp_param.replyopts.opt.opt.optlen; |
1da177e4 LT |
630 | room -= sizeof(struct icmphdr); |
631 | ||
632 | icmp_param.data_len = skb_in->len - icmp_param.offset; | |
633 | if (icmp_param.data_len > room) | |
634 | icmp_param.data_len = room; | |
635 | icmp_param.head_len = sizeof(struct icmphdr); | |
636 | ||
77968b78 | 637 | icmp_push_reply(&icmp_param, &fl4, &ipc, &rt); |
1da177e4 LT |
638 | ende: |
639 | ip_rt_put(rt); | |
640 | out_unlock: | |
405666db | 641 | icmp_xmit_unlock(sk); |
1da177e4 LT |
642 | out:; |
643 | } | |
4bc2f18b | 644 | EXPORT_SYMBOL(icmp_send); |
1da177e4 LT |
645 | |
646 | ||
1de9243b DM |
647 | static void icmp_socket_deliver(struct sk_buff *skb, u32 info) |
648 | { | |
649 | const struct iphdr *iph = (const struct iphdr *) skb->data; | |
650 | const struct net_protocol *ipprot; | |
651 | int protocol = iph->protocol; | |
652 | ||
f0a70e90 DM |
653 | /* Checkin full IP header plus 8 bytes of protocol to |
654 | * avoid additional coding at protocol handlers. | |
655 | */ | |
656 | if (!pskb_may_pull(skb, iph->ihl * 4 + 8)) | |
657 | return; | |
658 | ||
1de9243b DM |
659 | raw_icmp_error(skb, protocol, info); |
660 | ||
661 | rcu_read_lock(); | |
662 | ipprot = rcu_dereference(inet_protos[protocol]); | |
663 | if (ipprot && ipprot->err_handler) | |
664 | ipprot->err_handler(skb, info); | |
665 | rcu_read_unlock(); | |
666 | } | |
667 | ||
1da177e4 LT |
668 | /* |
669 | * Handle ICMP_DEST_UNREACH, ICMP_TIME_EXCEED, and ICMP_QUENCH. | |
670 | */ | |
671 | ||
672 | static void icmp_unreach(struct sk_buff *skb) | |
673 | { | |
b71d1d42 | 674 | const struct iphdr *iph; |
1da177e4 | 675 | struct icmphdr *icmph; |
dde1bc0e | 676 | struct net *net; |
f9242b6b | 677 | u32 info = 0; |
dde1bc0e | 678 | |
adf30907 | 679 | net = dev_net(skb_dst(skb)->dev); |
1da177e4 LT |
680 | |
681 | /* | |
682 | * Incomplete header ? | |
683 | * Only checks for the IP header, there should be an | |
684 | * additional check for longer headers in upper levels. | |
685 | */ | |
686 | ||
687 | if (!pskb_may_pull(skb, sizeof(struct iphdr))) | |
688 | goto out_err; | |
689 | ||
88c7664f | 690 | icmph = icmp_hdr(skb); |
b71d1d42 | 691 | iph = (const struct iphdr *)skb->data; |
1da177e4 LT |
692 | |
693 | if (iph->ihl < 5) /* Mangled header, drop. */ | |
694 | goto out_err; | |
695 | ||
696 | if (icmph->type == ICMP_DEST_UNREACH) { | |
697 | switch (icmph->code & 15) { | |
698 | case ICMP_NET_UNREACH: | |
699 | case ICMP_HOST_UNREACH: | |
700 | case ICMP_PROT_UNREACH: | |
701 | case ICMP_PORT_UNREACH: | |
702 | break; | |
703 | case ICMP_FRAG_NEEDED: | |
704 | if (ipv4_config.no_pmtu_disc) { | |
afd46503 | 705 | LIMIT_NETDEBUG(KERN_INFO pr_fmt("%pI4: fragmentation needed and DF set\n"), |
673d57e7 | 706 | &iph->daddr); |
1da177e4 | 707 | } else { |
46517008 | 708 | info = ntohs(icmph->un.frag.mtu); |
1da177e4 LT |
709 | } |
710 | break; | |
711 | case ICMP_SR_FAILED: | |
afd46503 | 712 | LIMIT_NETDEBUG(KERN_INFO pr_fmt("%pI4: Source Route Failed\n"), |
673d57e7 | 713 | &iph->daddr); |
1da177e4 LT |
714 | break; |
715 | default: | |
716 | break; | |
717 | } | |
718 | if (icmph->code > NR_ICMP_UNREACH) | |
719 | goto out; | |
720 | } else if (icmph->type == ICMP_PARAMETERPROB) | |
721 | info = ntohl(icmph->un.gateway) >> 24; | |
722 | ||
723 | /* | |
724 | * Throw it at our lower layers | |
725 | * | |
726 | * RFC 1122: 3.2.2 MUST extract the protocol ID from the passed | |
727 | * header. | |
728 | * RFC 1122: 3.2.2.1 MUST pass ICMP unreach messages to the | |
729 | * transport layer. | |
730 | * RFC 1122: 3.2.2.2 MUST pass ICMP time expired messages to | |
731 | * transport layer. | |
732 | */ | |
733 | ||
734 | /* | |
25985edc | 735 | * Check the other end isn't violating RFC 1122. Some routers send |
1da177e4 LT |
736 | * bogus responses to broadcast frames. If you see this message |
737 | * first check your netmask matches at both ends, if it does then | |
738 | * get the other vendor to fix their kit. | |
739 | */ | |
740 | ||
b34a95ee | 741 | if (!net->ipv4.sysctl_icmp_ignore_bogus_error_responses && |
dde1bc0e | 742 | inet_addr_type(net, iph->daddr) == RTN_BROADCAST) { |
e87cc472 JP |
743 | net_warn_ratelimited("%pI4 sent an invalid ICMP type %u, code %u error to a broadcast: %pI4 on %s\n", |
744 | &ip_hdr(skb)->saddr, | |
745 | icmph->type, icmph->code, | |
746 | &iph->daddr, skb->dev->name); | |
1da177e4 LT |
747 | goto out; |
748 | } | |
749 | ||
1de9243b | 750 | icmp_socket_deliver(skb, info); |
1da177e4 LT |
751 | |
752 | out: | |
753 | return; | |
754 | out_err: | |
dcfc23ca | 755 | ICMP_INC_STATS_BH(net, ICMP_MIB_INERRORS); |
1da177e4 LT |
756 | goto out; |
757 | } | |
758 | ||
759 | ||
760 | /* | |
761 | * Handle ICMP_REDIRECT. | |
762 | */ | |
763 | ||
764 | static void icmp_redirect(struct sk_buff *skb) | |
765 | { | |
94206125 DM |
766 | if (skb->len < sizeof(struct iphdr)) { |
767 | ICMP_INC_STATS_BH(dev_net(skb->dev), ICMP_MIB_INERRORS); | |
768 | return; | |
769 | } | |
1da177e4 | 770 | |
1da177e4 | 771 | if (!pskb_may_pull(skb, sizeof(struct iphdr))) |
94206125 | 772 | return; |
c319b4d7 | 773 | |
d3351b75 | 774 | icmp_socket_deliver(skb, icmp_hdr(skb)->un.gateway); |
1da177e4 LT |
775 | } |
776 | ||
777 | /* | |
778 | * Handle ICMP_ECHO ("ping") requests. | |
779 | * | |
780 | * RFC 1122: 3.2.2.6 MUST have an echo server that answers ICMP echo | |
781 | * requests. | |
782 | * RFC 1122: 3.2.2.6 Data received in the ICMP_ECHO request MUST be | |
783 | * included in the reply. | |
784 | * RFC 1812: 4.3.3.6 SHOULD have a config option for silently ignoring | |
785 | * echo requests, MUST have default=NOT. | |
786 | * See also WRT handling of options once they are done and working. | |
787 | */ | |
788 | ||
789 | static void icmp_echo(struct sk_buff *skb) | |
790 | { | |
b34a95ee PE |
791 | struct net *net; |
792 | ||
adf30907 | 793 | net = dev_net(skb_dst(skb)->dev); |
b34a95ee | 794 | if (!net->ipv4.sysctl_icmp_echo_ignore_all) { |
1da177e4 LT |
795 | struct icmp_bxm icmp_param; |
796 | ||
88c7664f | 797 | icmp_param.data.icmph = *icmp_hdr(skb); |
1da177e4 LT |
798 | icmp_param.data.icmph.type = ICMP_ECHOREPLY; |
799 | icmp_param.skb = skb; | |
800 | icmp_param.offset = 0; | |
801 | icmp_param.data_len = skb->len; | |
802 | icmp_param.head_len = sizeof(struct icmphdr); | |
803 | icmp_reply(&icmp_param, skb); | |
804 | } | |
805 | } | |
806 | ||
807 | /* | |
808 | * Handle ICMP Timestamp requests. | |
809 | * RFC 1122: 3.2.2.8 MAY implement ICMP timestamp requests. | |
810 | * SHOULD be in the kernel for minimum random latency. | |
811 | * MUST be accurate to a few minutes. | |
812 | * MUST be updated at least at 15Hz. | |
813 | */ | |
814 | static void icmp_timestamp(struct sk_buff *skb) | |
815 | { | |
f25c3d61 | 816 | struct timespec tv; |
1da177e4 LT |
817 | struct icmp_bxm icmp_param; |
818 | /* | |
819 | * Too short. | |
820 | */ | |
821 | if (skb->len < 4) | |
822 | goto out_err; | |
823 | ||
824 | /* | |
825 | * Fill in the current time as ms since midnight UT: | |
826 | */ | |
f25c3d61 YH |
827 | getnstimeofday(&tv); |
828 | icmp_param.data.times[1] = htonl((tv.tv_sec % 86400) * MSEC_PER_SEC + | |
829 | tv.tv_nsec / NSEC_PER_MSEC); | |
1da177e4 LT |
830 | icmp_param.data.times[2] = icmp_param.data.times[1]; |
831 | if (skb_copy_bits(skb, 0, &icmp_param.data.times[0], 4)) | |
832 | BUG(); | |
88c7664f | 833 | icmp_param.data.icmph = *icmp_hdr(skb); |
1da177e4 LT |
834 | icmp_param.data.icmph.type = ICMP_TIMESTAMPREPLY; |
835 | icmp_param.data.icmph.code = 0; | |
836 | icmp_param.skb = skb; | |
837 | icmp_param.offset = 0; | |
838 | icmp_param.data_len = 0; | |
839 | icmp_param.head_len = sizeof(struct icmphdr) + 12; | |
840 | icmp_reply(&icmp_param, skb); | |
841 | out: | |
842 | return; | |
843 | out_err: | |
adf30907 | 844 | ICMP_INC_STATS_BH(dev_net(skb_dst(skb)->dev), ICMP_MIB_INERRORS); |
1da177e4 LT |
845 | goto out; |
846 | } | |
847 | ||
1da177e4 LT |
848 | static void icmp_discard(struct sk_buff *skb) |
849 | { | |
850 | } | |
851 | ||
852 | /* | |
853 | * Deal with incoming ICMP packets. | |
854 | */ | |
855 | int icmp_rcv(struct sk_buff *skb) | |
856 | { | |
857 | struct icmphdr *icmph; | |
511c3f92 | 858 | struct rtable *rt = skb_rtable(skb); |
d8d1f30b | 859 | struct net *net = dev_net(rt->dst.dev); |
1da177e4 | 860 | |
aebcf82c | 861 | if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb)) { |
def8b4fa | 862 | struct sec_path *sp = skb_sec_path(skb); |
8b7817f3 HX |
863 | int nh; |
864 | ||
def8b4fa | 865 | if (!(sp && sp->xvec[sp->len - 1]->props.flags & |
aebcf82c HX |
866 | XFRM_STATE_ICMP)) |
867 | goto drop; | |
868 | ||
8b7817f3 HX |
869 | if (!pskb_may_pull(skb, sizeof(*icmph) + sizeof(struct iphdr))) |
870 | goto drop; | |
871 | ||
872 | nh = skb_network_offset(skb); | |
873 | skb_set_network_header(skb, sizeof(*icmph)); | |
874 | ||
875 | if (!xfrm4_policy_check_reverse(NULL, XFRM_POLICY_IN, skb)) | |
876 | goto drop; | |
877 | ||
878 | skb_set_network_header(skb, nh); | |
879 | } | |
880 | ||
dcfc23ca | 881 | ICMP_INC_STATS_BH(net, ICMP_MIB_INMSGS); |
1da177e4 LT |
882 | |
883 | switch (skb->ip_summed) { | |
84fa7933 | 884 | case CHECKSUM_COMPLETE: |
d3bc23e7 | 885 | if (!csum_fold(skb->csum)) |
1da177e4 | 886 | break; |
fb286bb2 | 887 | /* fall through */ |
1da177e4 | 888 | case CHECKSUM_NONE: |
fb286bb2 HX |
889 | skb->csum = 0; |
890 | if (__skb_checksum_complete(skb)) | |
6a5dc9e5 | 891 | goto csum_error; |
1da177e4 LT |
892 | } |
893 | ||
8cf22943 HX |
894 | if (!pskb_pull(skb, sizeof(*icmph))) |
895 | goto error; | |
1da177e4 | 896 | |
88c7664f | 897 | icmph = icmp_hdr(skb); |
1da177e4 | 898 | |
f66ac03d | 899 | ICMPMSGIN_INC_STATS_BH(net, icmph->type); |
1da177e4 LT |
900 | /* |
901 | * 18 is the highest 'known' ICMP type. Anything else is a mystery | |
902 | * | |
903 | * RFC 1122: 3.2.2 Unknown ICMP messages types MUST be silently | |
904 | * discarded. | |
905 | */ | |
906 | if (icmph->type > NR_ICMP_TYPES) | |
907 | goto error; | |
908 | ||
909 | ||
910 | /* | |
911 | * Parse the ICMP message | |
912 | */ | |
913 | ||
e905a9ed | 914 | if (rt->rt_flags & (RTCF_BROADCAST | RTCF_MULTICAST)) { |
1da177e4 LT |
915 | /* |
916 | * RFC 1122: 3.2.2.6 An ICMP_ECHO to broadcast MAY be | |
917 | * silently ignored (we let user decide with a sysctl). | |
918 | * RFC 1122: 3.2.2.8 An ICMP_TIMESTAMP MAY be silently | |
919 | * discarded if to broadcast/multicast. | |
920 | */ | |
4c866aa7 AK |
921 | if ((icmph->type == ICMP_ECHO || |
922 | icmph->type == ICMP_TIMESTAMP) && | |
b34a95ee | 923 | net->ipv4.sysctl_icmp_echo_ignore_broadcasts) { |
1da177e4 LT |
924 | goto error; |
925 | } | |
926 | if (icmph->type != ICMP_ECHO && | |
927 | icmph->type != ICMP_TIMESTAMP && | |
928 | icmph->type != ICMP_ADDRESS && | |
929 | icmph->type != ICMP_ADDRESSREPLY) { | |
930 | goto error; | |
e905a9ed | 931 | } |
1da177e4 LT |
932 | } |
933 | ||
1da177e4 LT |
934 | icmp_pointers[icmph->type].handler(skb); |
935 | ||
936 | drop: | |
937 | kfree_skb(skb); | |
938 | return 0; | |
6a5dc9e5 ED |
939 | csum_error: |
940 | ICMP_INC_STATS_BH(net, ICMP_MIB_CSUMERRORS); | |
1da177e4 | 941 | error: |
dcfc23ca | 942 | ICMP_INC_STATS_BH(net, ICMP_MIB_INERRORS); |
1da177e4 LT |
943 | goto drop; |
944 | } | |
945 | ||
5b052042 LW |
946 | void icmp_err(struct sk_buff *skb, u32 info) |
947 | { | |
948 | struct iphdr *iph = (struct iphdr *)skb->data; | |
3c2a0909 S |
949 | int offset = iph->ihl<<2; |
950 | struct icmphdr *icmph = (struct icmphdr *)(skb->data + offset); | |
5b052042 LW |
951 | int type = icmp_hdr(skb)->type; |
952 | int code = icmp_hdr(skb)->code; | |
953 | struct net *net = dev_net(skb->dev); | |
954 | ||
955 | /* | |
956 | * Use ping_err to handle all icmp errors except those | |
957 | * triggered by ICMP_ECHOREPLY which sent from kernel. | |
958 | */ | |
959 | if (icmph->type != ICMP_ECHOREPLY) { | |
3c2a0909 | 960 | ping_err(skb, offset, info); |
5b052042 LW |
961 | return; |
962 | } | |
963 | ||
964 | if (type == ICMP_DEST_UNREACH && code == ICMP_FRAG_NEEDED) | |
965 | ipv4_update_pmtu(skb, net, info, 0, 0, IPPROTO_ICMP, 0); | |
966 | else if (type == ICMP_REDIRECT) | |
967 | ipv4_redirect(skb, net, 0, 0, IPPROTO_ICMP, 0); | |
968 | } | |
969 | ||
1da177e4 LT |
970 | /* |
971 | * This table is the definition of how we handle ICMP. | |
972 | */ | |
9b5b5cff | 973 | static const struct icmp_control icmp_pointers[NR_ICMP_TYPES + 1] = { |
1da177e4 | 974 | [ICMP_ECHOREPLY] = { |
c319b4d7 | 975 | .handler = ping_rcv, |
1da177e4 LT |
976 | }, |
977 | [1] = { | |
1da177e4 LT |
978 | .handler = icmp_discard, |
979 | .error = 1, | |
980 | }, | |
981 | [2] = { | |
1da177e4 LT |
982 | .handler = icmp_discard, |
983 | .error = 1, | |
984 | }, | |
985 | [ICMP_DEST_UNREACH] = { | |
1da177e4 LT |
986 | .handler = icmp_unreach, |
987 | .error = 1, | |
988 | }, | |
989 | [ICMP_SOURCE_QUENCH] = { | |
1da177e4 LT |
990 | .handler = icmp_unreach, |
991 | .error = 1, | |
992 | }, | |
993 | [ICMP_REDIRECT] = { | |
1da177e4 LT |
994 | .handler = icmp_redirect, |
995 | .error = 1, | |
996 | }, | |
997 | [6] = { | |
1da177e4 LT |
998 | .handler = icmp_discard, |
999 | .error = 1, | |
1000 | }, | |
1001 | [7] = { | |
1da177e4 LT |
1002 | .handler = icmp_discard, |
1003 | .error = 1, | |
1004 | }, | |
1005 | [ICMP_ECHO] = { | |
1da177e4 LT |
1006 | .handler = icmp_echo, |
1007 | }, | |
1008 | [9] = { | |
1da177e4 LT |
1009 | .handler = icmp_discard, |
1010 | .error = 1, | |
1011 | }, | |
1012 | [10] = { | |
1da177e4 LT |
1013 | .handler = icmp_discard, |
1014 | .error = 1, | |
1015 | }, | |
1016 | [ICMP_TIME_EXCEEDED] = { | |
1da177e4 LT |
1017 | .handler = icmp_unreach, |
1018 | .error = 1, | |
1019 | }, | |
1020 | [ICMP_PARAMETERPROB] = { | |
1da177e4 LT |
1021 | .handler = icmp_unreach, |
1022 | .error = 1, | |
1023 | }, | |
1024 | [ICMP_TIMESTAMP] = { | |
1da177e4 LT |
1025 | .handler = icmp_timestamp, |
1026 | }, | |
1027 | [ICMP_TIMESTAMPREPLY] = { | |
1da177e4 LT |
1028 | .handler = icmp_discard, |
1029 | }, | |
1030 | [ICMP_INFO_REQUEST] = { | |
1da177e4 LT |
1031 | .handler = icmp_discard, |
1032 | }, | |
e905a9ed | 1033 | [ICMP_INFO_REPLY] = { |
1da177e4 LT |
1034 | .handler = icmp_discard, |
1035 | }, | |
1036 | [ICMP_ADDRESS] = { | |
838942a5 | 1037 | .handler = icmp_discard, |
1da177e4 LT |
1038 | }, |
1039 | [ICMP_ADDRESSREPLY] = { | |
838942a5 | 1040 | .handler = icmp_discard, |
1da177e4 LT |
1041 | }, |
1042 | }; | |
1043 | ||
4a6ad7a1 | 1044 | static void __net_exit icmp_sk_exit(struct net *net) |
1da177e4 | 1045 | { |
1da177e4 LT |
1046 | int i; |
1047 | ||
5c8cafd6 | 1048 | for_each_possible_cpu(i) |
c1e9894d | 1049 | inet_ctl_sock_destroy(net->ipv4.icmp_sk[i]); |
4a6ad7a1 DL |
1050 | kfree(net->ipv4.icmp_sk); |
1051 | net->ipv4.icmp_sk = NULL; | |
a5710d65 | 1052 | } |
1da177e4 | 1053 | |
263173af | 1054 | static int __net_init icmp_sk_init(struct net *net) |
a5710d65 | 1055 | { |
a5710d65 DL |
1056 | int i, err; |
1057 | ||
4a6ad7a1 DL |
1058 | net->ipv4.icmp_sk = |
1059 | kzalloc(nr_cpu_ids * sizeof(struct sock *), GFP_KERNEL); | |
1060 | if (net->ipv4.icmp_sk == NULL) | |
79c91159 DL |
1061 | return -ENOMEM; |
1062 | ||
a5710d65 | 1063 | for_each_possible_cpu(i) { |
1e3cf683 | 1064 | struct sock *sk; |
1da177e4 | 1065 | |
c1e9894d DL |
1066 | err = inet_ctl_sock_create(&sk, PF_INET, |
1067 | SOCK_RAW, IPPROTO_ICMP, net); | |
1da177e4 | 1068 | if (err < 0) |
a5710d65 | 1069 | goto fail; |
1da177e4 | 1070 | |
c1e9894d | 1071 | net->ipv4.icmp_sk[i] = sk; |
1da177e4 LT |
1072 | |
1073 | /* Enough space for 2 64K ICMP packets, including | |
87fb4b7b | 1074 | * sk_buff/skb_shared_info struct overhead. |
1da177e4 | 1075 | */ |
87fb4b7b | 1076 | sk->sk_sndbuf = 2 * SKB_TRUESIZE(64 * 1024); |
1da177e4 | 1077 | |
b3a5b6cc ED |
1078 | /* |
1079 | * Speedup sock_wfree() | |
1080 | */ | |
1081 | sock_set_flag(sk, SOCK_USE_WRITE_QUEUE); | |
c1e9894d | 1082 | inet_sk(sk)->pmtudisc = IP_PMTUDISC_DONT; |
1da177e4 | 1083 | } |
a24022e1 PE |
1084 | |
1085 | /* Control parameters for ECHO replies. */ | |
1086 | net->ipv4.sysctl_icmp_echo_ignore_all = 0; | |
1087 | net->ipv4.sysctl_icmp_echo_ignore_broadcasts = 1; | |
1088 | ||
1089 | /* Control parameter - ignore bogus broadcast responses? */ | |
1090 | net->ipv4.sysctl_icmp_ignore_bogus_error_responses = 1; | |
1091 | ||
1092 | /* | |
1093 | * Configurable global rate limit. | |
1094 | * | |
1095 | * ratelimit defines tokens/packet consumed for dst->rate_token | |
1096 | * bucket ratemask defines which icmp types are ratelimited by | |
1097 | * setting it's bit position. | |
1098 | * | |
1099 | * default: | |
1100 | * dest unreachable (3), source quench (4), | |
1101 | * time exceeded (11), parameter problem (12) | |
1102 | */ | |
1103 | ||
1104 | net->ipv4.sysctl_icmp_ratelimit = 1 * HZ; | |
1105 | net->ipv4.sysctl_icmp_ratemask = 0x1818; | |
1106 | net->ipv4.sysctl_icmp_errors_use_inbound_ifaddr = 0; | |
1107 | ||
a5710d65 DL |
1108 | return 0; |
1109 | ||
1110 | fail: | |
1d1c8d13 | 1111 | for_each_possible_cpu(i) |
c1e9894d | 1112 | inet_ctl_sock_destroy(net->ipv4.icmp_sk[i]); |
1d1c8d13 | 1113 | kfree(net->ipv4.icmp_sk); |
a5710d65 | 1114 | return err; |
1da177e4 LT |
1115 | } |
1116 | ||
4a6ad7a1 DL |
1117 | static struct pernet_operations __net_initdata icmp_sk_ops = { |
1118 | .init = icmp_sk_init, | |
1119 | .exit = icmp_sk_exit, | |
1120 | }; | |
1121 | ||
1122 | int __init icmp_init(void) | |
1123 | { | |
959d2726 | 1124 | return register_pernet_subsys(&icmp_sk_ops); |
4a6ad7a1 | 1125 | } |