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; |
1da177e4 | 340 | |
f6d8bd05 | 341 | if (ip_options_echo(&icmp_param->replyopts.opt.opt, skb)) |
f00c401b | 342 | return; |
1da177e4 | 343 | |
fdc0bde9 DL |
344 | sk = icmp_xmit_lock(net); |
345 | if (sk == NULL) | |
1da177e4 | 346 | return; |
fdc0bde9 | 347 | inet = inet_sk(sk); |
1da177e4 LT |
348 | |
349 | icmp_param->data.icmph.checksum = 0; | |
1da177e4 | 350 | |
eddc9ec5 | 351 | inet->tos = ip_hdr(skb)->tos; |
9f6abb5f | 352 | daddr = ipc.addr = ip_hdr(skb)->saddr; |
35ebf65e | 353 | saddr = fib_compute_spec_dst(skb); |
1da177e4 | 354 | ipc.opt = NULL; |
2244d07b | 355 | ipc.tx_flags = 0; |
aa661581 FF |
356 | ipc.ttl = 0; |
357 | ipc.tos = -1; | |
358 | ||
f6d8bd05 ED |
359 | if (icmp_param->replyopts.opt.opt.optlen) { |
360 | ipc.opt = &icmp_param->replyopts.opt; | |
361 | if (ipc.opt->opt.srr) | |
362 | daddr = icmp_param->replyopts.opt.opt.faddr; | |
1da177e4 | 363 | } |
77968b78 DM |
364 | memset(&fl4, 0, sizeof(fl4)); |
365 | fl4.daddr = daddr; | |
35ebf65e | 366 | fl4.saddr = saddr; |
77968b78 DM |
367 | fl4.flowi4_tos = RT_TOS(ip_hdr(skb)->tos); |
368 | fl4.flowi4_proto = IPPROTO_ICMP; | |
369 | security_skb_classify_flow(skb, flowi4_to_flowi(&fl4)); | |
370 | rt = ip_route_output_key(net, &fl4); | |
371 | if (IS_ERR(rt)) | |
372 | goto out_unlock; | |
a48eff12 | 373 | if (icmpv4_xrlim_allow(net, rt, &fl4, icmp_param->data.icmph.type, |
1da177e4 | 374 | icmp_param->data.icmph.code)) |
77968b78 | 375 | icmp_push_reply(icmp_param, &fl4, &ipc, &rt); |
1da177e4 LT |
376 | ip_rt_put(rt); |
377 | out_unlock: | |
405666db | 378 | icmp_xmit_unlock(sk); |
1da177e4 LT |
379 | } |
380 | ||
77968b78 DM |
381 | static struct rtable *icmp_route_lookup(struct net *net, |
382 | struct flowi4 *fl4, | |
383 | struct sk_buff *skb_in, | |
b71d1d42 | 384 | const struct iphdr *iph, |
f6d460cf DM |
385 | __be32 saddr, u8 tos, |
386 | int type, int code, | |
387 | struct icmp_bxm *param) | |
388 | { | |
f6d460cf | 389 | struct rtable *rt, *rt2; |
415b3334 | 390 | struct flowi4 fl4_dec; |
f6d460cf DM |
391 | int err; |
392 | ||
77968b78 DM |
393 | memset(fl4, 0, sizeof(*fl4)); |
394 | fl4->daddr = (param->replyopts.opt.opt.srr ? | |
395 | param->replyopts.opt.opt.faddr : iph->saddr); | |
396 | fl4->saddr = saddr; | |
397 | fl4->flowi4_tos = RT_TOS(tos); | |
398 | fl4->flowi4_proto = IPPROTO_ICMP; | |
399 | fl4->fl4_icmp_type = type; | |
400 | fl4->fl4_icmp_code = code; | |
401 | security_skb_classify_flow(skb_in, flowi4_to_flowi(fl4)); | |
402 | rt = __ip_route_output_key(net, fl4); | |
b23dd4fe DM |
403 | if (IS_ERR(rt)) |
404 | return rt; | |
f6d460cf DM |
405 | |
406 | /* No need to clone since we're just using its address. */ | |
407 | rt2 = rt; | |
408 | ||
9d6ec938 | 409 | rt = (struct rtable *) xfrm_lookup(net, &rt->dst, |
77968b78 | 410 | flowi4_to_flowi(fl4), NULL, 0); |
452edd59 | 411 | if (!IS_ERR(rt)) { |
f6d460cf DM |
412 | if (rt != rt2) |
413 | return rt; | |
452edd59 | 414 | } else if (PTR_ERR(rt) == -EPERM) { |
f6d460cf | 415 | rt = NULL; |
452edd59 DM |
416 | } else |
417 | return rt; | |
f6d460cf | 418 | |
415b3334 | 419 | err = xfrm_decode_session_reverse(skb_in, flowi4_to_flowi(&fl4_dec), AF_INET); |
f6d460cf DM |
420 | if (err) |
421 | goto relookup_failed; | |
422 | ||
415b3334 DM |
423 | if (inet_addr_type(net, fl4_dec.saddr) == RTN_LOCAL) { |
424 | rt2 = __ip_route_output_key(net, &fl4_dec); | |
b23dd4fe DM |
425 | if (IS_ERR(rt2)) |
426 | err = PTR_ERR(rt2); | |
f6d460cf | 427 | } else { |
9d6ec938 | 428 | struct flowi4 fl4_2 = {}; |
f6d460cf DM |
429 | unsigned long orefdst; |
430 | ||
415b3334 | 431 | fl4_2.daddr = fl4_dec.saddr; |
9d6ec938 | 432 | rt2 = ip_route_output_key(net, &fl4_2); |
b23dd4fe DM |
433 | if (IS_ERR(rt2)) { |
434 | err = PTR_ERR(rt2); | |
f6d460cf | 435 | goto relookup_failed; |
b23dd4fe | 436 | } |
f6d460cf DM |
437 | /* Ugh! */ |
438 | orefdst = skb_in->_skb_refdst; /* save old refdst */ | |
415b3334 | 439 | err = ip_route_input(skb_in, fl4_dec.daddr, fl4_dec.saddr, |
f6d460cf DM |
440 | RT_TOS(tos), rt2->dst.dev); |
441 | ||
442 | dst_release(&rt2->dst); | |
443 | rt2 = skb_rtable(skb_in); | |
444 | skb_in->_skb_refdst = orefdst; /* restore old refdst */ | |
445 | } | |
446 | ||
447 | if (err) | |
448 | goto relookup_failed; | |
449 | ||
9d6ec938 | 450 | rt2 = (struct rtable *) xfrm_lookup(net, &rt2->dst, |
415b3334 | 451 | flowi4_to_flowi(&fl4_dec), NULL, |
9d6ec938 | 452 | XFRM_LOOKUP_ICMP); |
452edd59 | 453 | if (!IS_ERR(rt2)) { |
f6d460cf | 454 | dst_release(&rt->dst); |
415b3334 | 455 | memcpy(fl4, &fl4_dec, sizeof(*fl4)); |
f6d460cf | 456 | rt = rt2; |
452edd59 DM |
457 | } else if (PTR_ERR(rt2) == -EPERM) { |
458 | if (rt) | |
459 | dst_release(&rt->dst); | |
460 | return rt2; | |
461 | } else { | |
462 | err = PTR_ERR(rt2); | |
463 | goto relookup_failed; | |
f6d460cf | 464 | } |
f6d460cf DM |
465 | return rt; |
466 | ||
467 | relookup_failed: | |
468 | if (rt) | |
469 | return rt; | |
470 | return ERR_PTR(err); | |
471 | } | |
1da177e4 LT |
472 | |
473 | /* | |
474 | * Send an ICMP message in response to a situation | |
475 | * | |
476 | * RFC 1122: 3.2.2 MUST send at least the IP header and 8 bytes of header. | |
477 | * MAY send more (we do). | |
478 | * MUST NOT change this header information. | |
479 | * MUST NOT reply to a multicast/broadcast IP address. | |
480 | * MUST NOT reply to a multicast/broadcast MAC address. | |
481 | * MUST reply to only the first fragment. | |
482 | */ | |
483 | ||
e4883014 | 484 | void icmp_send(struct sk_buff *skb_in, int type, int code, __be32 info) |
1da177e4 LT |
485 | { |
486 | struct iphdr *iph; | |
487 | int room; | |
9a99d4a5 | 488 | struct icmp_bxm *icmp_param; |
511c3f92 | 489 | struct rtable *rt = skb_rtable(skb_in); |
1da177e4 | 490 | struct ipcm_cookie ipc; |
77968b78 | 491 | struct flowi4 fl4; |
a61ced5d | 492 | __be32 saddr; |
1da177e4 | 493 | u8 tos; |
dde1bc0e | 494 | struct net *net; |
4a6ad7a1 | 495 | struct sock *sk; |
1da177e4 LT |
496 | |
497 | if (!rt) | |
498 | goto out; | |
d8d1f30b | 499 | net = dev_net(rt->dst.dev); |
1da177e4 LT |
500 | |
501 | /* | |
502 | * Find the original header. It is expected to be valid, of course. | |
503 | * Check this, icmp_send is called from the most obscure devices | |
504 | * sometimes. | |
505 | */ | |
eddc9ec5 | 506 | iph = ip_hdr(skb_in); |
1da177e4 | 507 | |
27a884dc | 508 | if ((u8 *)iph < skb_in->head || |
f7c0c2ae SH |
509 | (skb_network_header(skb_in) + sizeof(*iph)) > |
510 | skb_tail_pointer(skb_in)) | |
1da177e4 LT |
511 | goto out; |
512 | ||
513 | /* | |
514 | * No replies to physical multicast/broadcast | |
515 | */ | |
516 | if (skb_in->pkt_type != PACKET_HOST) | |
517 | goto out; | |
518 | ||
519 | /* | |
520 | * Now check at the protocol level | |
521 | */ | |
522 | if (rt->rt_flags & (RTCF_BROADCAST | RTCF_MULTICAST)) | |
523 | goto out; | |
524 | ||
525 | /* | |
526 | * Only reply to fragment 0. We byte re-order the constant | |
527 | * mask for efficiency. | |
528 | */ | |
529 | if (iph->frag_off & htons(IP_OFFSET)) | |
530 | goto out; | |
531 | ||
532 | /* | |
533 | * If we send an ICMP error to an ICMP error a mess would result.. | |
534 | */ | |
535 | if (icmp_pointers[type].error) { | |
536 | /* | |
537 | * We are an error, check if we are replying to an | |
538 | * ICMP error | |
539 | */ | |
540 | if (iph->protocol == IPPROTO_ICMP) { | |
541 | u8 _inner_type, *itp; | |
542 | ||
543 | itp = skb_header_pointer(skb_in, | |
d56f90a7 | 544 | skb_network_header(skb_in) + |
1da177e4 LT |
545 | (iph->ihl << 2) + |
546 | offsetof(struct icmphdr, | |
547 | type) - | |
548 | skb_in->data, | |
549 | sizeof(_inner_type), | |
550 | &_inner_type); | |
551 | if (itp == NULL) | |
552 | goto out; | |
553 | ||
554 | /* | |
555 | * Assume any unknown ICMP type is an error. This | |
556 | * isn't specified by the RFC, but think about it.. | |
557 | */ | |
558 | if (*itp > NR_ICMP_TYPES || | |
559 | icmp_pointers[*itp].error) | |
560 | goto out; | |
561 | } | |
562 | } | |
563 | ||
9a99d4a5 CW |
564 | icmp_param = kmalloc(sizeof(*icmp_param), GFP_ATOMIC); |
565 | if (!icmp_param) | |
566 | return; | |
567 | ||
fdc0bde9 DL |
568 | sk = icmp_xmit_lock(net); |
569 | if (sk == NULL) | |
9a99d4a5 | 570 | goto out_free; |
1da177e4 LT |
571 | |
572 | /* | |
573 | * Construct source address and options. | |
574 | */ | |
575 | ||
576 | saddr = iph->daddr; | |
1c2fb7f9 | 577 | if (!(rt->rt_flags & RTCF_LOCAL)) { |
6e1d9103 PM |
578 | struct net_device *dev = NULL; |
579 | ||
685c7944 | 580 | rcu_read_lock(); |
c7537967 DM |
581 | if (rt_is_input_route(rt) && |
582 | net->ipv4.sysctl_icmp_errors_use_inbound_ifaddr) | |
92101b3b | 583 | dev = dev_get_by_index_rcu(net, inet_iif(skb_in)); |
6e1d9103 | 584 | |
685c7944 | 585 | if (dev) |
6e1d9103 | 586 | saddr = inet_select_addr(dev, 0, RT_SCOPE_LINK); |
685c7944 | 587 | else |
1c2fb7f9 | 588 | saddr = 0; |
685c7944 | 589 | rcu_read_unlock(); |
1c2fb7f9 | 590 | } |
1da177e4 LT |
591 | |
592 | tos = icmp_pointers[type].error ? ((iph->tos & IPTOS_TOS_MASK) | | |
593 | IPTOS_PREC_INTERNETCONTROL) : | |
594 | iph->tos; | |
595 | ||
9a99d4a5 | 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 | ||
9a99d4a5 CW |
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; | |
609 | icmp_param->offset = skb_network_offset(skb_in); | |
405666db | 610 | inet_sk(sk)->tos = tos; |
1da177e4 | 611 | ipc.addr = iph->saddr; |
9a99d4a5 | 612 | ipc.opt = &icmp_param->replyopts.opt; |
2244d07b | 613 | ipc.tx_flags = 0; |
aa661581 FF |
614 | ipc.ttl = 0; |
615 | ipc.tos = -1; | |
1da177e4 | 616 | |
77968b78 | 617 | rt = icmp_route_lookup(net, &fl4, skb_in, iph, saddr, tos, |
9a99d4a5 | 618 | type, code, icmp_param); |
f6d460cf DM |
619 | if (IS_ERR(rt)) |
620 | goto out_unlock; | |
1da177e4 | 621 | |
a48eff12 | 622 | if (!icmpv4_xrlim_allow(net, rt, &fl4, type, code)) |
1da177e4 LT |
623 | goto ende; |
624 | ||
625 | /* RFC says return as much as we can without exceeding 576 bytes. */ | |
626 | ||
d8d1f30b | 627 | room = dst_mtu(&rt->dst); |
1da177e4 LT |
628 | if (room > 576) |
629 | room = 576; | |
9a99d4a5 | 630 | room -= sizeof(struct iphdr) + icmp_param->replyopts.opt.opt.optlen; |
1da177e4 LT |
631 | room -= sizeof(struct icmphdr); |
632 | ||
9a99d4a5 CW |
633 | icmp_param->data_len = skb_in->len - icmp_param->offset; |
634 | if (icmp_param->data_len > room) | |
635 | icmp_param->data_len = room; | |
636 | icmp_param->head_len = sizeof(struct icmphdr); | |
1da177e4 | 637 | |
9a99d4a5 | 638 | icmp_push_reply(icmp_param, &fl4, &ipc, &rt); |
1da177e4 LT |
639 | ende: |
640 | ip_rt_put(rt); | |
641 | out_unlock: | |
405666db | 642 | icmp_xmit_unlock(sk); |
9a99d4a5 CW |
643 | out_free: |
644 | kfree(icmp_param); | |
1da177e4 LT |
645 | out:; |
646 | } | |
4bc2f18b | 647 | EXPORT_SYMBOL(icmp_send); |
1da177e4 LT |
648 | |
649 | ||
1de9243b DM |
650 | static void icmp_socket_deliver(struct sk_buff *skb, u32 info) |
651 | { | |
652 | const struct iphdr *iph = (const struct iphdr *) skb->data; | |
653 | const struct net_protocol *ipprot; | |
654 | int protocol = iph->protocol; | |
655 | ||
f0a70e90 DM |
656 | /* Checkin full IP header plus 8 bytes of protocol to |
657 | * avoid additional coding at protocol handlers. | |
658 | */ | |
659 | if (!pskb_may_pull(skb, iph->ihl * 4 + 8)) | |
660 | return; | |
661 | ||
1de9243b DM |
662 | raw_icmp_error(skb, protocol, info); |
663 | ||
664 | rcu_read_lock(); | |
665 | ipprot = rcu_dereference(inet_protos[protocol]); | |
666 | if (ipprot && ipprot->err_handler) | |
667 | ipprot->err_handler(skb, info); | |
668 | rcu_read_unlock(); | |
669 | } | |
670 | ||
8ed1dc44 HFS |
671 | static bool icmp_tag_validation(int proto) |
672 | { | |
673 | bool ok; | |
674 | ||
675 | rcu_read_lock(); | |
676 | ok = rcu_dereference(inet_protos[proto])->icmp_strict_tag_validation; | |
677 | rcu_read_unlock(); | |
678 | return ok; | |
679 | } | |
680 | ||
1da177e4 | 681 | /* |
08578d8d RR |
682 | * Handle ICMP_DEST_UNREACH, ICMP_TIME_EXCEED, ICMP_QUENCH, and |
683 | * ICMP_PARAMETERPROB. | |
1da177e4 LT |
684 | */ |
685 | ||
686 | static void icmp_unreach(struct sk_buff *skb) | |
687 | { | |
b71d1d42 | 688 | const struct iphdr *iph; |
1da177e4 | 689 | struct icmphdr *icmph; |
dde1bc0e | 690 | struct net *net; |
f9242b6b | 691 | u32 info = 0; |
dde1bc0e | 692 | |
adf30907 | 693 | net = dev_net(skb_dst(skb)->dev); |
1da177e4 LT |
694 | |
695 | /* | |
696 | * Incomplete header ? | |
697 | * Only checks for the IP header, there should be an | |
698 | * additional check for longer headers in upper levels. | |
699 | */ | |
700 | ||
701 | if (!pskb_may_pull(skb, sizeof(struct iphdr))) | |
702 | goto out_err; | |
703 | ||
88c7664f | 704 | icmph = icmp_hdr(skb); |
b71d1d42 | 705 | iph = (const struct iphdr *)skb->data; |
1da177e4 LT |
706 | |
707 | if (iph->ihl < 5) /* Mangled header, drop. */ | |
708 | goto out_err; | |
709 | ||
710 | if (icmph->type == ICMP_DEST_UNREACH) { | |
711 | switch (icmph->code & 15) { | |
712 | case ICMP_NET_UNREACH: | |
713 | case ICMP_HOST_UNREACH: | |
714 | case ICMP_PROT_UNREACH: | |
715 | case ICMP_PORT_UNREACH: | |
716 | break; | |
717 | case ICMP_FRAG_NEEDED: | |
8ed1dc44 HFS |
718 | /* for documentation of the ip_no_pmtu_disc |
719 | * values please see | |
720 | * Documentation/networking/ip-sysctl.txt | |
721 | */ | |
722 | switch (net->ipv4.sysctl_ip_no_pmtu_disc) { | |
723 | default: | |
afd46503 | 724 | LIMIT_NETDEBUG(KERN_INFO pr_fmt("%pI4: fragmentation needed and DF set\n"), |
673d57e7 | 725 | &iph->daddr); |
8ed1dc44 HFS |
726 | break; |
727 | case 2: | |
728 | goto out; | |
729 | case 3: | |
730 | if (!icmp_tag_validation(iph->protocol)) | |
731 | goto out; | |
732 | /* fall through */ | |
733 | case 0: | |
46517008 | 734 | info = ntohs(icmph->un.frag.mtu); |
1da177e4 LT |
735 | if (!info) |
736 | goto out; | |
737 | } | |
738 | break; | |
739 | case ICMP_SR_FAILED: | |
afd46503 | 740 | LIMIT_NETDEBUG(KERN_INFO pr_fmt("%pI4: Source Route Failed\n"), |
673d57e7 | 741 | &iph->daddr); |
1da177e4 LT |
742 | break; |
743 | default: | |
744 | break; | |
745 | } | |
746 | if (icmph->code > NR_ICMP_UNREACH) | |
747 | goto out; | |
748 | } else if (icmph->type == ICMP_PARAMETERPROB) | |
749 | info = ntohl(icmph->un.gateway) >> 24; | |
750 | ||
751 | /* | |
752 | * Throw it at our lower layers | |
753 | * | |
754 | * RFC 1122: 3.2.2 MUST extract the protocol ID from the passed | |
755 | * header. | |
756 | * RFC 1122: 3.2.2.1 MUST pass ICMP unreach messages to the | |
757 | * transport layer. | |
758 | * RFC 1122: 3.2.2.2 MUST pass ICMP time expired messages to | |
759 | * transport layer. | |
760 | */ | |
761 | ||
762 | /* | |
25985edc | 763 | * Check the other end isn't violating RFC 1122. Some routers send |
1da177e4 LT |
764 | * bogus responses to broadcast frames. If you see this message |
765 | * first check your netmask matches at both ends, if it does then | |
766 | * get the other vendor to fix their kit. | |
767 | */ | |
768 | ||
b34a95ee | 769 | if (!net->ipv4.sysctl_icmp_ignore_bogus_error_responses && |
dde1bc0e | 770 | inet_addr_type(net, iph->daddr) == RTN_BROADCAST) { |
e87cc472 JP |
771 | net_warn_ratelimited("%pI4 sent an invalid ICMP type %u, code %u error to a broadcast: %pI4 on %s\n", |
772 | &ip_hdr(skb)->saddr, | |
773 | icmph->type, icmph->code, | |
774 | &iph->daddr, skb->dev->name); | |
1da177e4 LT |
775 | goto out; |
776 | } | |
777 | ||
1de9243b | 778 | icmp_socket_deliver(skb, info); |
1da177e4 LT |
779 | |
780 | out: | |
781 | return; | |
782 | out_err: | |
dcfc23ca | 783 | ICMP_INC_STATS_BH(net, ICMP_MIB_INERRORS); |
1da177e4 LT |
784 | goto out; |
785 | } | |
786 | ||
787 | ||
788 | /* | |
789 | * Handle ICMP_REDIRECT. | |
790 | */ | |
791 | ||
792 | static void icmp_redirect(struct sk_buff *skb) | |
793 | { | |
94206125 DM |
794 | if (skb->len < sizeof(struct iphdr)) { |
795 | ICMP_INC_STATS_BH(dev_net(skb->dev), ICMP_MIB_INERRORS); | |
796 | return; | |
797 | } | |
1da177e4 | 798 | |
1da177e4 | 799 | if (!pskb_may_pull(skb, sizeof(struct iphdr))) |
94206125 | 800 | return; |
c319b4d7 | 801 | |
d3351b75 | 802 | icmp_socket_deliver(skb, icmp_hdr(skb)->un.gateway); |
1da177e4 LT |
803 | } |
804 | ||
805 | /* | |
806 | * Handle ICMP_ECHO ("ping") requests. | |
807 | * | |
808 | * RFC 1122: 3.2.2.6 MUST have an echo server that answers ICMP echo | |
809 | * requests. | |
810 | * RFC 1122: 3.2.2.6 Data received in the ICMP_ECHO request MUST be | |
811 | * included in the reply. | |
812 | * RFC 1812: 4.3.3.6 SHOULD have a config option for silently ignoring | |
813 | * echo requests, MUST have default=NOT. | |
814 | * See also WRT handling of options once they are done and working. | |
815 | */ | |
816 | ||
817 | static void icmp_echo(struct sk_buff *skb) | |
818 | { | |
b34a95ee PE |
819 | struct net *net; |
820 | ||
adf30907 | 821 | net = dev_net(skb_dst(skb)->dev); |
b34a95ee | 822 | if (!net->ipv4.sysctl_icmp_echo_ignore_all) { |
1da177e4 LT |
823 | struct icmp_bxm icmp_param; |
824 | ||
88c7664f | 825 | icmp_param.data.icmph = *icmp_hdr(skb); |
1da177e4 LT |
826 | icmp_param.data.icmph.type = ICMP_ECHOREPLY; |
827 | icmp_param.skb = skb; | |
828 | icmp_param.offset = 0; | |
829 | icmp_param.data_len = skb->len; | |
830 | icmp_param.head_len = sizeof(struct icmphdr); | |
831 | icmp_reply(&icmp_param, skb); | |
832 | } | |
833 | } | |
834 | ||
835 | /* | |
836 | * Handle ICMP Timestamp requests. | |
837 | * RFC 1122: 3.2.2.8 MAY implement ICMP timestamp requests. | |
838 | * SHOULD be in the kernel for minimum random latency. | |
839 | * MUST be accurate to a few minutes. | |
840 | * MUST be updated at least at 15Hz. | |
841 | */ | |
842 | static void icmp_timestamp(struct sk_buff *skb) | |
843 | { | |
f25c3d61 | 844 | struct timespec tv; |
1da177e4 LT |
845 | struct icmp_bxm icmp_param; |
846 | /* | |
847 | * Too short. | |
848 | */ | |
849 | if (skb->len < 4) | |
850 | goto out_err; | |
851 | ||
852 | /* | |
853 | * Fill in the current time as ms since midnight UT: | |
854 | */ | |
f25c3d61 YH |
855 | getnstimeofday(&tv); |
856 | icmp_param.data.times[1] = htonl((tv.tv_sec % 86400) * MSEC_PER_SEC + | |
857 | tv.tv_nsec / NSEC_PER_MSEC); | |
1da177e4 LT |
858 | icmp_param.data.times[2] = icmp_param.data.times[1]; |
859 | if (skb_copy_bits(skb, 0, &icmp_param.data.times[0], 4)) | |
860 | BUG(); | |
88c7664f | 861 | icmp_param.data.icmph = *icmp_hdr(skb); |
1da177e4 LT |
862 | icmp_param.data.icmph.type = ICMP_TIMESTAMPREPLY; |
863 | icmp_param.data.icmph.code = 0; | |
864 | icmp_param.skb = skb; | |
865 | icmp_param.offset = 0; | |
866 | icmp_param.data_len = 0; | |
867 | icmp_param.head_len = sizeof(struct icmphdr) + 12; | |
868 | icmp_reply(&icmp_param, skb); | |
869 | out: | |
870 | return; | |
871 | out_err: | |
adf30907 | 872 | ICMP_INC_STATS_BH(dev_net(skb_dst(skb)->dev), ICMP_MIB_INERRORS); |
1da177e4 LT |
873 | goto out; |
874 | } | |
875 | ||
1da177e4 LT |
876 | static void icmp_discard(struct sk_buff *skb) |
877 | { | |
878 | } | |
879 | ||
880 | /* | |
881 | * Deal with incoming ICMP packets. | |
882 | */ | |
883 | int icmp_rcv(struct sk_buff *skb) | |
884 | { | |
885 | struct icmphdr *icmph; | |
511c3f92 | 886 | struct rtable *rt = skb_rtable(skb); |
d8d1f30b | 887 | struct net *net = dev_net(rt->dst.dev); |
1da177e4 | 888 | |
aebcf82c | 889 | if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb)) { |
def8b4fa | 890 | struct sec_path *sp = skb_sec_path(skb); |
8b7817f3 HX |
891 | int nh; |
892 | ||
def8b4fa | 893 | if (!(sp && sp->xvec[sp->len - 1]->props.flags & |
aebcf82c HX |
894 | XFRM_STATE_ICMP)) |
895 | goto drop; | |
896 | ||
8b7817f3 HX |
897 | if (!pskb_may_pull(skb, sizeof(*icmph) + sizeof(struct iphdr))) |
898 | goto drop; | |
899 | ||
900 | nh = skb_network_offset(skb); | |
901 | skb_set_network_header(skb, sizeof(*icmph)); | |
902 | ||
903 | if (!xfrm4_policy_check_reverse(NULL, XFRM_POLICY_IN, skb)) | |
904 | goto drop; | |
905 | ||
906 | skb_set_network_header(skb, nh); | |
907 | } | |
908 | ||
dcfc23ca | 909 | ICMP_INC_STATS_BH(net, ICMP_MIB_INMSGS); |
1da177e4 LT |
910 | |
911 | switch (skb->ip_summed) { | |
84fa7933 | 912 | case CHECKSUM_COMPLETE: |
d3bc23e7 | 913 | if (!csum_fold(skb->csum)) |
1da177e4 | 914 | break; |
fb286bb2 | 915 | /* fall through */ |
1da177e4 | 916 | case CHECKSUM_NONE: |
fb286bb2 HX |
917 | skb->csum = 0; |
918 | if (__skb_checksum_complete(skb)) | |
6a5dc9e5 | 919 | goto csum_error; |
1da177e4 LT |
920 | } |
921 | ||
8cf22943 HX |
922 | if (!pskb_pull(skb, sizeof(*icmph))) |
923 | goto error; | |
1da177e4 | 924 | |
88c7664f | 925 | icmph = icmp_hdr(skb); |
1da177e4 | 926 | |
f66ac03d | 927 | ICMPMSGIN_INC_STATS_BH(net, icmph->type); |
1da177e4 LT |
928 | /* |
929 | * 18 is the highest 'known' ICMP type. Anything else is a mystery | |
930 | * | |
931 | * RFC 1122: 3.2.2 Unknown ICMP messages types MUST be silently | |
932 | * discarded. | |
933 | */ | |
934 | if (icmph->type > NR_ICMP_TYPES) | |
935 | goto error; | |
936 | ||
937 | ||
938 | /* | |
939 | * Parse the ICMP message | |
940 | */ | |
941 | ||
e905a9ed | 942 | if (rt->rt_flags & (RTCF_BROADCAST | RTCF_MULTICAST)) { |
1da177e4 LT |
943 | /* |
944 | * RFC 1122: 3.2.2.6 An ICMP_ECHO to broadcast MAY be | |
945 | * silently ignored (we let user decide with a sysctl). | |
946 | * RFC 1122: 3.2.2.8 An ICMP_TIMESTAMP MAY be silently | |
947 | * discarded if to broadcast/multicast. | |
948 | */ | |
4c866aa7 AK |
949 | if ((icmph->type == ICMP_ECHO || |
950 | icmph->type == ICMP_TIMESTAMP) && | |
b34a95ee | 951 | net->ipv4.sysctl_icmp_echo_ignore_broadcasts) { |
1da177e4 LT |
952 | goto error; |
953 | } | |
954 | if (icmph->type != ICMP_ECHO && | |
955 | icmph->type != ICMP_TIMESTAMP && | |
956 | icmph->type != ICMP_ADDRESS && | |
957 | icmph->type != ICMP_ADDRESSREPLY) { | |
958 | goto error; | |
e905a9ed | 959 | } |
1da177e4 LT |
960 | } |
961 | ||
1da177e4 LT |
962 | icmp_pointers[icmph->type].handler(skb); |
963 | ||
964 | drop: | |
965 | kfree_skb(skb); | |
966 | return 0; | |
6a5dc9e5 ED |
967 | csum_error: |
968 | ICMP_INC_STATS_BH(net, ICMP_MIB_CSUMERRORS); | |
1da177e4 | 969 | error: |
dcfc23ca | 970 | ICMP_INC_STATS_BH(net, ICMP_MIB_INERRORS); |
1da177e4 LT |
971 | goto drop; |
972 | } | |
973 | ||
5b052042 LW |
974 | void icmp_err(struct sk_buff *skb, u32 info) |
975 | { | |
976 | struct iphdr *iph = (struct iphdr *)skb->data; | |
6d0bfe22 LC |
977 | int offset = iph->ihl<<2; |
978 | struct icmphdr *icmph = (struct icmphdr *)(skb->data + offset); | |
5b052042 LW |
979 | int type = icmp_hdr(skb)->type; |
980 | int code = icmp_hdr(skb)->code; | |
981 | struct net *net = dev_net(skb->dev); | |
982 | ||
983 | /* | |
984 | * Use ping_err to handle all icmp errors except those | |
985 | * triggered by ICMP_ECHOREPLY which sent from kernel. | |
986 | */ | |
987 | if (icmph->type != ICMP_ECHOREPLY) { | |
6d0bfe22 | 988 | ping_err(skb, offset, info); |
5b052042 LW |
989 | return; |
990 | } | |
991 | ||
992 | if (type == ICMP_DEST_UNREACH && code == ICMP_FRAG_NEEDED) | |
993 | ipv4_update_pmtu(skb, net, info, 0, 0, IPPROTO_ICMP, 0); | |
994 | else if (type == ICMP_REDIRECT) | |
995 | ipv4_redirect(skb, net, 0, 0, IPPROTO_ICMP, 0); | |
996 | } | |
997 | ||
1da177e4 LT |
998 | /* |
999 | * This table is the definition of how we handle ICMP. | |
1000 | */ | |
9b5b5cff | 1001 | static const struct icmp_control icmp_pointers[NR_ICMP_TYPES + 1] = { |
1da177e4 | 1002 | [ICMP_ECHOREPLY] = { |
c319b4d7 | 1003 | .handler = ping_rcv, |
1da177e4 LT |
1004 | }, |
1005 | [1] = { | |
1da177e4 LT |
1006 | .handler = icmp_discard, |
1007 | .error = 1, | |
1008 | }, | |
1009 | [2] = { | |
1da177e4 LT |
1010 | .handler = icmp_discard, |
1011 | .error = 1, | |
1012 | }, | |
1013 | [ICMP_DEST_UNREACH] = { | |
1da177e4 LT |
1014 | .handler = icmp_unreach, |
1015 | .error = 1, | |
1016 | }, | |
1017 | [ICMP_SOURCE_QUENCH] = { | |
1da177e4 LT |
1018 | .handler = icmp_unreach, |
1019 | .error = 1, | |
1020 | }, | |
1021 | [ICMP_REDIRECT] = { | |
1da177e4 LT |
1022 | .handler = icmp_redirect, |
1023 | .error = 1, | |
1024 | }, | |
1025 | [6] = { | |
1da177e4 LT |
1026 | .handler = icmp_discard, |
1027 | .error = 1, | |
1028 | }, | |
1029 | [7] = { | |
1da177e4 LT |
1030 | .handler = icmp_discard, |
1031 | .error = 1, | |
1032 | }, | |
1033 | [ICMP_ECHO] = { | |
1da177e4 LT |
1034 | .handler = icmp_echo, |
1035 | }, | |
1036 | [9] = { | |
1da177e4 LT |
1037 | .handler = icmp_discard, |
1038 | .error = 1, | |
1039 | }, | |
1040 | [10] = { | |
1da177e4 LT |
1041 | .handler = icmp_discard, |
1042 | .error = 1, | |
1043 | }, | |
1044 | [ICMP_TIME_EXCEEDED] = { | |
1da177e4 LT |
1045 | .handler = icmp_unreach, |
1046 | .error = 1, | |
1047 | }, | |
1048 | [ICMP_PARAMETERPROB] = { | |
1da177e4 LT |
1049 | .handler = icmp_unreach, |
1050 | .error = 1, | |
1051 | }, | |
1052 | [ICMP_TIMESTAMP] = { | |
1da177e4 LT |
1053 | .handler = icmp_timestamp, |
1054 | }, | |
1055 | [ICMP_TIMESTAMPREPLY] = { | |
1da177e4 LT |
1056 | .handler = icmp_discard, |
1057 | }, | |
1058 | [ICMP_INFO_REQUEST] = { | |
1da177e4 LT |
1059 | .handler = icmp_discard, |
1060 | }, | |
e905a9ed | 1061 | [ICMP_INFO_REPLY] = { |
1da177e4 LT |
1062 | .handler = icmp_discard, |
1063 | }, | |
1064 | [ICMP_ADDRESS] = { | |
838942a5 | 1065 | .handler = icmp_discard, |
1da177e4 LT |
1066 | }, |
1067 | [ICMP_ADDRESSREPLY] = { | |
838942a5 | 1068 | .handler = icmp_discard, |
1da177e4 LT |
1069 | }, |
1070 | }; | |
1071 | ||
4a6ad7a1 | 1072 | static void __net_exit icmp_sk_exit(struct net *net) |
1da177e4 | 1073 | { |
1da177e4 LT |
1074 | int i; |
1075 | ||
5c8cafd6 | 1076 | for_each_possible_cpu(i) |
c1e9894d | 1077 | inet_ctl_sock_destroy(net->ipv4.icmp_sk[i]); |
4a6ad7a1 DL |
1078 | kfree(net->ipv4.icmp_sk); |
1079 | net->ipv4.icmp_sk = NULL; | |
a5710d65 | 1080 | } |
1da177e4 | 1081 | |
263173af | 1082 | static int __net_init icmp_sk_init(struct net *net) |
a5710d65 | 1083 | { |
a5710d65 DL |
1084 | int i, err; |
1085 | ||
4a6ad7a1 DL |
1086 | net->ipv4.icmp_sk = |
1087 | kzalloc(nr_cpu_ids * sizeof(struct sock *), GFP_KERNEL); | |
1088 | if (net->ipv4.icmp_sk == NULL) | |
79c91159 DL |
1089 | return -ENOMEM; |
1090 | ||
a5710d65 | 1091 | for_each_possible_cpu(i) { |
1e3cf683 | 1092 | struct sock *sk; |
1da177e4 | 1093 | |
c1e9894d DL |
1094 | err = inet_ctl_sock_create(&sk, PF_INET, |
1095 | SOCK_RAW, IPPROTO_ICMP, net); | |
1da177e4 | 1096 | if (err < 0) |
a5710d65 | 1097 | goto fail; |
1da177e4 | 1098 | |
c1e9894d | 1099 | net->ipv4.icmp_sk[i] = sk; |
1da177e4 LT |
1100 | |
1101 | /* Enough space for 2 64K ICMP packets, including | |
87fb4b7b | 1102 | * sk_buff/skb_shared_info struct overhead. |
1da177e4 | 1103 | */ |
87fb4b7b | 1104 | sk->sk_sndbuf = 2 * SKB_TRUESIZE(64 * 1024); |
1da177e4 | 1105 | |
b3a5b6cc ED |
1106 | /* |
1107 | * Speedup sock_wfree() | |
1108 | */ | |
1109 | sock_set_flag(sk, SOCK_USE_WRITE_QUEUE); | |
c1e9894d | 1110 | inet_sk(sk)->pmtudisc = IP_PMTUDISC_DONT; |
1da177e4 | 1111 | } |
a24022e1 PE |
1112 | |
1113 | /* Control parameters for ECHO replies. */ | |
1114 | net->ipv4.sysctl_icmp_echo_ignore_all = 0; | |
1115 | net->ipv4.sysctl_icmp_echo_ignore_broadcasts = 1; | |
1116 | ||
1117 | /* Control parameter - ignore bogus broadcast responses? */ | |
1118 | net->ipv4.sysctl_icmp_ignore_bogus_error_responses = 1; | |
1119 | ||
1120 | /* | |
1121 | * Configurable global rate limit. | |
1122 | * | |
1123 | * ratelimit defines tokens/packet consumed for dst->rate_token | |
1124 | * bucket ratemask defines which icmp types are ratelimited by | |
1125 | * setting it's bit position. | |
1126 | * | |
1127 | * default: | |
1128 | * dest unreachable (3), source quench (4), | |
1129 | * time exceeded (11), parameter problem (12) | |
1130 | */ | |
1131 | ||
1132 | net->ipv4.sysctl_icmp_ratelimit = 1 * HZ; | |
1133 | net->ipv4.sysctl_icmp_ratemask = 0x1818; | |
1134 | net->ipv4.sysctl_icmp_errors_use_inbound_ifaddr = 0; | |
1135 | ||
a5710d65 DL |
1136 | return 0; |
1137 | ||
1138 | fail: | |
1d1c8d13 | 1139 | for_each_possible_cpu(i) |
c1e9894d | 1140 | inet_ctl_sock_destroy(net->ipv4.icmp_sk[i]); |
1d1c8d13 | 1141 | kfree(net->ipv4.icmp_sk); |
a5710d65 | 1142 | return err; |
1da177e4 LT |
1143 | } |
1144 | ||
4a6ad7a1 DL |
1145 | static struct pernet_operations __net_initdata icmp_sk_ops = { |
1146 | .init = icmp_sk_init, | |
1147 | .exit = icmp_sk_exit, | |
1148 | }; | |
1149 | ||
1150 | int __init icmp_init(void) | |
1151 | { | |
959d2726 | 1152 | return register_pernet_subsys(&icmp_sk_ops); |
4a6ad7a1 | 1153 | } |