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Commit | Line | Data |
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f0cbd3ec FB |
1 | /* |
2 | * Copyright (c) 1982, 1986, 1988, 1993 | |
3 | * The Regents of the University of California. All rights reserved. | |
4 | * | |
5 | * Redistribution and use in source and binary forms, with or without | |
6 | * modification, are permitted provided that the following conditions | |
7 | * are met: | |
8 | * 1. Redistributions of source code must retain the above copyright | |
9 | * notice, this list of conditions and the following disclaimer. | |
10 | * 2. Redistributions in binary form must reproduce the above copyright | |
11 | * notice, this list of conditions and the following disclaimer in the | |
12 | * documentation and/or other materials provided with the distribution. | |
2f5f8996 | 13 | * 3. Neither the name of the University nor the names of its contributors |
f0cbd3ec FB |
14 | * may be used to endorse or promote products derived from this software |
15 | * without specific prior written permission. | |
16 | * | |
17 | * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND | |
18 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE | |
19 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE | |
20 | * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE | |
21 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL | |
22 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS | |
23 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) | |
24 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT | |
25 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY | |
26 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF | |
27 | * SUCH DAMAGE. | |
28 | * | |
29 | * @(#)ip_input.c 8.2 (Berkeley) 1/4/94 | |
30 | * ip_input.c,v 1.11 1994/11/16 10:17:08 jkh Exp | |
31 | */ | |
32 | ||
33 | /* | |
34 | * Changes and additions relating to SLiRP are | |
35 | * Copyright (c) 1995 Danny Gasparovski. | |
5fafdf24 | 36 | * |
f0cbd3ec FB |
37 | * Please read the file COPYRIGHT for the |
38 | * terms and conditions of the copyright. | |
39 | */ | |
40 | ||
41 | #include <slirp.h> | |
429d0a3d | 42 | #include <osdep.h> |
f0cbd3ec FB |
43 | #include "ip_icmp.h" |
44 | ||
31a60e22 | 45 | #ifdef LOG_ENABLED |
f0cbd3ec | 46 | struct ipstat ipstat; |
31a60e22 BS |
47 | #endif |
48 | ||
f0cbd3ec FB |
49 | struct ipq ipq; |
50 | ||
429d0a3d | 51 | static struct ip *ip_reass(register struct ip *ip, |
9634d903 BS |
52 | register struct ipq *fp); |
53 | static void ip_freef(struct ipq *fp); | |
54 | static void ip_enq(register struct ipasfrag *p, | |
55 | register struct ipasfrag *prev); | |
56 | static void ip_deq(register struct ipasfrag *p); | |
57 | ||
f0cbd3ec FB |
58 | /* |
59 | * IP initialization: fill in IP protocol switch table. | |
60 | * All protocols not implemented in kernel go to raw IP protocol handler. | |
61 | */ | |
62 | void | |
63 | ip_init() | |
64 | { | |
429d0a3d | 65 | ipq.ip_link.next = ipq.ip_link.prev = &ipq.ip_link; |
f0cbd3ec FB |
66 | ip_id = tt.tv_sec & 0xffff; |
67 | udp_init(); | |
68 | tcp_init(); | |
f0cbd3ec FB |
69 | } |
70 | ||
71 | /* | |
72 | * Ip input routine. Checksum and byte swap header. If fragmented | |
73 | * try to reassemble. Process options. Pass to next level. | |
74 | */ | |
75 | void | |
76 | ip_input(m) | |
77 | struct mbuf *m; | |
78 | { | |
79 | register struct ip *ip; | |
80 | int hlen; | |
5fafdf24 | 81 | |
f0cbd3ec FB |
82 | DEBUG_CALL("ip_input"); |
83 | DEBUG_ARG("m = %lx", (long)m); | |
84 | DEBUG_ARG("m_len = %d", m->m_len); | |
85 | ||
31a60e22 | 86 | STAT(ipstat.ips_total++); |
5fafdf24 | 87 | |
f0cbd3ec | 88 | if (m->m_len < sizeof (struct ip)) { |
31a60e22 | 89 | STAT(ipstat.ips_toosmall++); |
f0cbd3ec FB |
90 | return; |
91 | } | |
5fafdf24 | 92 | |
f0cbd3ec | 93 | ip = mtod(m, struct ip *); |
5fafdf24 | 94 | |
f0cbd3ec | 95 | if (ip->ip_v != IPVERSION) { |
31a60e22 | 96 | STAT(ipstat.ips_badvers++); |
f0cbd3ec FB |
97 | goto bad; |
98 | } | |
99 | ||
100 | hlen = ip->ip_hl << 2; | |
101 | if (hlen<sizeof(struct ip ) || hlen>m->m_len) {/* min header length */ | |
31a60e22 | 102 | STAT(ipstat.ips_badhlen++); /* or packet too short */ |
f0cbd3ec FB |
103 | goto bad; |
104 | } | |
105 | ||
106 | /* keep ip header intact for ICMP reply | |
5fafdf24 TS |
107 | * ip->ip_sum = cksum(m, hlen); |
108 | * if (ip->ip_sum) { | |
f0cbd3ec FB |
109 | */ |
110 | if(cksum(m,hlen)) { | |
31a60e22 | 111 | STAT(ipstat.ips_badsum++); |
f0cbd3ec FB |
112 | goto bad; |
113 | } | |
114 | ||
115 | /* | |
116 | * Convert fields to host representation. | |
117 | */ | |
118 | NTOHS(ip->ip_len); | |
119 | if (ip->ip_len < hlen) { | |
31a60e22 | 120 | STAT(ipstat.ips_badlen++); |
f0cbd3ec FB |
121 | goto bad; |
122 | } | |
123 | NTOHS(ip->ip_id); | |
124 | NTOHS(ip->ip_off); | |
125 | ||
126 | /* | |
127 | * Check that the amount of data in the buffers | |
128 | * is as at least much as the IP header would have us expect. | |
129 | * Trim mbufs if longer than we expect. | |
130 | * Drop packet if shorter than we expect. | |
131 | */ | |
132 | if (m->m_len < ip->ip_len) { | |
31a60e22 | 133 | STAT(ipstat.ips_tooshort++); |
f0cbd3ec FB |
134 | goto bad; |
135 | } | |
a9ba3a85 AL |
136 | |
137 | if (slirp_restrict) { | |
138 | if (memcmp(&ip->ip_dst.s_addr, &special_addr, 3)) { | |
139 | if (ip->ip_dst.s_addr == 0xffffffff && ip->ip_p != IPPROTO_UDP) | |
140 | goto bad; | |
141 | } else { | |
142 | int host = ntohl(ip->ip_dst.s_addr) & 0xff; | |
143 | struct ex_list *ex_ptr; | |
144 | ||
145 | if (host == 0xff) | |
146 | goto bad; | |
147 | ||
148 | for (ex_ptr = exec_list; ex_ptr; ex_ptr = ex_ptr->ex_next) | |
149 | if (ex_ptr->ex_addr == host) | |
150 | break; | |
151 | ||
152 | if (!ex_ptr) | |
153 | goto bad; | |
154 | } | |
155 | } | |
156 | ||
f0cbd3ec FB |
157 | /* Should drop packet if mbuf too long? hmmm... */ |
158 | if (m->m_len > ip->ip_len) | |
159 | m_adj(m, ip->ip_len - m->m_len); | |
160 | ||
161 | /* check ip_ttl for a correct ICMP reply */ | |
162 | if(ip->ip_ttl==0 || ip->ip_ttl==1) { | |
163 | icmp_error(m, ICMP_TIMXCEED,ICMP_TIMXCEED_INTRANS, 0,"ttl"); | |
164 | goto bad; | |
165 | } | |
166 | ||
167 | /* | |
168 | * Process options and, if not destined for us, | |
169 | * ship it on. ip_dooptions returns 1 when an | |
170 | * error was detected (causing an icmp message | |
171 | * to be sent and the original packet to be freed). | |
172 | */ | |
173 | /* We do no IP options */ | |
174 | /* if (hlen > sizeof (struct ip) && ip_dooptions(m)) | |
175 | * goto next; | |
176 | */ | |
177 | /* | |
178 | * If offset or IP_MF are set, must reassemble. | |
179 | * Otherwise, nothing need be done. | |
180 | * (We could look in the reassembly queue to see | |
181 | * if the packet was previously fragmented, | |
182 | * but it's not worth the time; just let them time out.) | |
5fafdf24 | 183 | * |
f0cbd3ec FB |
184 | * XXX This should fail, don't fragment yet |
185 | */ | |
186 | if (ip->ip_off &~ IP_DF) { | |
187 | register struct ipq *fp; | |
429d0a3d | 188 | struct qlink *l; |
f0cbd3ec FB |
189 | /* |
190 | * Look for queue of fragments | |
191 | * of this datagram. | |
192 | */ | |
429d0a3d BS |
193 | for (l = ipq.ip_link.next; l != &ipq.ip_link; l = l->next) { |
194 | fp = container_of(l, struct ipq, ip_link); | |
195 | if (ip->ip_id == fp->ipq_id && | |
196 | ip->ip_src.s_addr == fp->ipq_src.s_addr && | |
197 | ip->ip_dst.s_addr == fp->ipq_dst.s_addr && | |
198 | ip->ip_p == fp->ipq_p) | |
f0cbd3ec | 199 | goto found; |
429d0a3d BS |
200 | } |
201 | fp = NULL; | |
f0cbd3ec FB |
202 | found: |
203 | ||
204 | /* | |
205 | * Adjust ip_len to not reflect header, | |
206 | * set ip_mff if more fragments are expected, | |
207 | * convert offset of this to bytes. | |
208 | */ | |
209 | ip->ip_len -= hlen; | |
210 | if (ip->ip_off & IP_MF) | |
429d0a3d | 211 | ip->ip_tos |= 1; |
5fafdf24 | 212 | else |
429d0a3d | 213 | ip->ip_tos &= ~1; |
f0cbd3ec FB |
214 | |
215 | ip->ip_off <<= 3; | |
216 | ||
217 | /* | |
218 | * If datagram marked as having more fragments | |
219 | * or if this is not the first fragment, | |
220 | * attempt reassembly; if it succeeds, proceed. | |
221 | */ | |
429d0a3d | 222 | if (ip->ip_tos & 1 || ip->ip_off) { |
31a60e22 | 223 | STAT(ipstat.ips_fragments++); |
429d0a3d | 224 | ip = ip_reass(ip, fp); |
f0cbd3ec FB |
225 | if (ip == 0) |
226 | return; | |
31a60e22 | 227 | STAT(ipstat.ips_reassembled++); |
f0cbd3ec FB |
228 | m = dtom(ip); |
229 | } else | |
230 | if (fp) | |
231 | ip_freef(fp); | |
232 | ||
233 | } else | |
234 | ip->ip_len -= hlen; | |
235 | ||
236 | /* | |
237 | * Switch out to protocol's input routine. | |
238 | */ | |
31a60e22 | 239 | STAT(ipstat.ips_delivered++); |
f0cbd3ec FB |
240 | switch (ip->ip_p) { |
241 | case IPPROTO_TCP: | |
242 | tcp_input(m, hlen, (struct socket *)NULL); | |
243 | break; | |
244 | case IPPROTO_UDP: | |
245 | udp_input(m, hlen); | |
246 | break; | |
247 | case IPPROTO_ICMP: | |
248 | icmp_input(m, hlen); | |
249 | break; | |
250 | default: | |
31a60e22 | 251 | STAT(ipstat.ips_noproto++); |
f0cbd3ec FB |
252 | m_free(m); |
253 | } | |
254 | return; | |
255 | bad: | |
256 | m_freem(m); | |
257 | return; | |
258 | } | |
259 | ||
429d0a3d BS |
260 | #define iptofrag(P) ((struct ipasfrag *)(((char*)(P)) - sizeof(struct qlink))) |
261 | #define fragtoip(P) ((struct ip*)(((char*)(P)) + sizeof(struct qlink))) | |
f0cbd3ec FB |
262 | /* |
263 | * Take incoming datagram fragment and try to | |
264 | * reassemble it into whole datagram. If a chain for | |
265 | * reassembly of this datagram already exists, then it | |
266 | * is given as fp; otherwise have to make a chain. | |
267 | */ | |
9634d903 | 268 | static struct ip * |
429d0a3d | 269 | ip_reass(register struct ip *ip, register struct ipq *fp) |
f0cbd3ec FB |
270 | { |
271 | register struct mbuf *m = dtom(ip); | |
272 | register struct ipasfrag *q; | |
273 | int hlen = ip->ip_hl << 2; | |
274 | int i, next; | |
5fafdf24 | 275 | |
f0cbd3ec FB |
276 | DEBUG_CALL("ip_reass"); |
277 | DEBUG_ARG("ip = %lx", (long)ip); | |
278 | DEBUG_ARG("fp = %lx", (long)fp); | |
279 | DEBUG_ARG("m = %lx", (long)m); | |
280 | ||
281 | /* | |
282 | * Presence of header sizes in mbufs | |
283 | * would confuse code below. | |
284 | * Fragment m_data is concatenated. | |
285 | */ | |
286 | m->m_data += hlen; | |
287 | m->m_len -= hlen; | |
288 | ||
289 | /* | |
290 | * If first fragment to arrive, create a reassembly queue. | |
291 | */ | |
292 | if (fp == 0) { | |
293 | struct mbuf *t; | |
294 | if ((t = m_get()) == NULL) goto dropfrag; | |
295 | fp = mtod(t, struct ipq *); | |
429d0a3d | 296 | insque(&fp->ip_link, &ipq.ip_link); |
f0cbd3ec FB |
297 | fp->ipq_ttl = IPFRAGTTL; |
298 | fp->ipq_p = ip->ip_p; | |
299 | fp->ipq_id = ip->ip_id; | |
429d0a3d BS |
300 | fp->frag_link.next = fp->frag_link.prev = &fp->frag_link; |
301 | fp->ipq_src = ip->ip_src; | |
302 | fp->ipq_dst = ip->ip_dst; | |
f0cbd3ec FB |
303 | q = (struct ipasfrag *)fp; |
304 | goto insert; | |
305 | } | |
5fafdf24 | 306 | |
f0cbd3ec FB |
307 | /* |
308 | * Find a segment which begins after this one does. | |
309 | */ | |
429d0a3d BS |
310 | for (q = fp->frag_link.next; q != (struct ipasfrag *)&fp->frag_link; |
311 | q = q->ipf_next) | |
312 | if (q->ipf_off > ip->ip_off) | |
f0cbd3ec FB |
313 | break; |
314 | ||
315 | /* | |
316 | * If there is a preceding segment, it may provide some of | |
317 | * our data already. If so, drop the data from the incoming | |
318 | * segment. If it provides all of our data, drop us. | |
319 | */ | |
429d0a3d BS |
320 | if (q->ipf_prev != &fp->frag_link) { |
321 | struct ipasfrag *pq = q->ipf_prev; | |
322 | i = pq->ipf_off + pq->ipf_len - ip->ip_off; | |
f0cbd3ec FB |
323 | if (i > 0) { |
324 | if (i >= ip->ip_len) | |
325 | goto dropfrag; | |
326 | m_adj(dtom(ip), i); | |
327 | ip->ip_off += i; | |
328 | ip->ip_len -= i; | |
329 | } | |
330 | } | |
331 | ||
332 | /* | |
333 | * While we overlap succeeding segments trim them or, | |
334 | * if they are completely covered, dequeue them. | |
335 | */ | |
429d0a3d BS |
336 | while (q != (struct ipasfrag*)&fp->frag_link && |
337 | ip->ip_off + ip->ip_len > q->ipf_off) { | |
338 | i = (ip->ip_off + ip->ip_len) - q->ipf_off; | |
339 | if (i < q->ipf_len) { | |
340 | q->ipf_len -= i; | |
341 | q->ipf_off += i; | |
f0cbd3ec FB |
342 | m_adj(dtom(q), i); |
343 | break; | |
344 | } | |
429d0a3d BS |
345 | q = q->ipf_next; |
346 | m_freem(dtom(q->ipf_prev)); | |
347 | ip_deq(q->ipf_prev); | |
f0cbd3ec FB |
348 | } |
349 | ||
350 | insert: | |
351 | /* | |
352 | * Stick new segment in its place; | |
353 | * check for complete reassembly. | |
354 | */ | |
429d0a3d | 355 | ip_enq(iptofrag(ip), q->ipf_prev); |
f0cbd3ec | 356 | next = 0; |
429d0a3d BS |
357 | for (q = fp->frag_link.next; q != (struct ipasfrag*)&fp->frag_link; |
358 | q = q->ipf_next) { | |
359 | if (q->ipf_off != next) | |
f0cbd3ec | 360 | return (0); |
429d0a3d | 361 | next += q->ipf_len; |
f0cbd3ec | 362 | } |
429d0a3d | 363 | if (((struct ipasfrag *)(q->ipf_prev))->ipf_tos & 1) |
f0cbd3ec FB |
364 | return (0); |
365 | ||
366 | /* | |
367 | * Reassembly is complete; concatenate fragments. | |
368 | */ | |
429d0a3d | 369 | q = fp->frag_link.next; |
f0cbd3ec FB |
370 | m = dtom(q); |
371 | ||
372 | q = (struct ipasfrag *) q->ipf_next; | |
429d0a3d BS |
373 | while (q != (struct ipasfrag*)&fp->frag_link) { |
374 | struct mbuf *t = dtom(q); | |
f0cbd3ec | 375 | q = (struct ipasfrag *) q->ipf_next; |
fedc54ad | 376 | m_cat(m, t); |
f0cbd3ec FB |
377 | } |
378 | ||
379 | /* | |
380 | * Create header for new ip packet by | |
381 | * modifying header of first packet; | |
382 | * dequeue and discard fragment reassembly header. | |
383 | * Make header visible. | |
384 | */ | |
429d0a3d | 385 | q = fp->frag_link.next; |
f0cbd3ec FB |
386 | |
387 | /* | |
388 | * If the fragments concatenated to an mbuf that's | |
389 | * bigger than the total size of the fragment, then and | |
390 | * m_ext buffer was alloced. But fp->ipq_next points to | |
391 | * the old buffer (in the mbuf), so we must point ip | |
392 | * into the new buffer. | |
393 | */ | |
394 | if (m->m_flags & M_EXT) { | |
395 | int delta; | |
396 | delta = (char *)ip - m->m_dat; | |
429d0a3d | 397 | q = (struct ipasfrag *)(m->m_ext + delta); |
f0cbd3ec FB |
398 | } |
399 | ||
5fafdf24 | 400 | /* DEBUG_ARG("ip = %lx", (long)ip); |
f0cbd3ec FB |
401 | * ip=(struct ipasfrag *)m->m_data; */ |
402 | ||
429d0a3d | 403 | ip = fragtoip(q); |
f0cbd3ec | 404 | ip->ip_len = next; |
429d0a3d BS |
405 | ip->ip_tos &= ~1; |
406 | ip->ip_src = fp->ipq_src; | |
407 | ip->ip_dst = fp->ipq_dst; | |
408 | remque(&fp->ip_link); | |
f0cbd3ec | 409 | (void) m_free(dtom(fp)); |
f0cbd3ec FB |
410 | m->m_len += (ip->ip_hl << 2); |
411 | m->m_data -= (ip->ip_hl << 2); | |
412 | ||
429d0a3d | 413 | return ip; |
f0cbd3ec FB |
414 | |
415 | dropfrag: | |
31a60e22 | 416 | STAT(ipstat.ips_fragdropped++); |
f0cbd3ec FB |
417 | m_freem(m); |
418 | return (0); | |
419 | } | |
420 | ||
421 | /* | |
422 | * Free a fragment reassembly header and all | |
423 | * associated datagrams. | |
424 | */ | |
9634d903 BS |
425 | static void |
426 | ip_freef(struct ipq *fp) | |
f0cbd3ec FB |
427 | { |
428 | register struct ipasfrag *q, *p; | |
429 | ||
429d0a3d BS |
430 | for (q = fp->frag_link.next; q != (struct ipasfrag*)&fp->frag_link; q = p) { |
431 | p = q->ipf_next; | |
f0cbd3ec FB |
432 | ip_deq(q); |
433 | m_freem(dtom(q)); | |
434 | } | |
429d0a3d | 435 | remque(&fp->ip_link); |
f0cbd3ec FB |
436 | (void) m_free(dtom(fp)); |
437 | } | |
438 | ||
439 | /* | |
440 | * Put an ip fragment on a reassembly chain. | |
441 | * Like insque, but pointers in middle of structure. | |
442 | */ | |
9634d903 BS |
443 | static void |
444 | ip_enq(register struct ipasfrag *p, register struct ipasfrag *prev) | |
f0cbd3ec FB |
445 | { |
446 | DEBUG_CALL("ip_enq"); | |
447 | DEBUG_ARG("prev = %lx", (long)prev); | |
429d0a3d | 448 | p->ipf_prev = prev; |
f0cbd3ec | 449 | p->ipf_next = prev->ipf_next; |
429d0a3d BS |
450 | ((struct ipasfrag *)(prev->ipf_next))->ipf_prev = p; |
451 | prev->ipf_next = p; | |
f0cbd3ec FB |
452 | } |
453 | ||
454 | /* | |
455 | * To ip_enq as remque is to insque. | |
456 | */ | |
9634d903 BS |
457 | static void |
458 | ip_deq(register struct ipasfrag *p) | |
f0cbd3ec FB |
459 | { |
460 | ((struct ipasfrag *)(p->ipf_prev))->ipf_next = p->ipf_next; | |
461 | ((struct ipasfrag *)(p->ipf_next))->ipf_prev = p->ipf_prev; | |
462 | } | |
463 | ||
464 | /* | |
465 | * IP timer processing; | |
466 | * if a timer expires on a reassembly | |
467 | * queue, discard it. | |
468 | */ | |
469 | void | |
470 | ip_slowtimo() | |
471 | { | |
429d0a3d | 472 | struct qlink *l; |
5fafdf24 | 473 | |
f0cbd3ec | 474 | DEBUG_CALL("ip_slowtimo"); |
5fafdf24 | 475 | |
429d0a3d BS |
476 | l = ipq.ip_link.next; |
477 | ||
478 | if (l == 0) | |
f0cbd3ec FB |
479 | return; |
480 | ||
429d0a3d BS |
481 | while (l != &ipq.ip_link) { |
482 | struct ipq *fp = container_of(l, struct ipq, ip_link); | |
483 | l = l->next; | |
484 | if (--fp->ipq_ttl == 0) { | |
31a60e22 | 485 | STAT(ipstat.ips_fragtimeout++); |
429d0a3d | 486 | ip_freef(fp); |
f0cbd3ec FB |
487 | } |
488 | } | |
489 | } | |
490 | ||
491 | /* | |
492 | * Do option processing on a datagram, | |
493 | * possibly discarding it if bad options are encountered, | |
494 | * or forwarding it if source-routed. | |
495 | * Returns 1 if packet has been forwarded/freed, | |
496 | * 0 if the packet should be processed further. | |
497 | */ | |
498 | ||
499 | #ifdef notdef | |
500 | ||
501 | int | |
502 | ip_dooptions(m) | |
503 | struct mbuf *m; | |
504 | { | |
505 | register struct ip *ip = mtod(m, struct ip *); | |
506 | register u_char *cp; | |
507 | register struct ip_timestamp *ipt; | |
508 | register struct in_ifaddr *ia; | |
509 | /* int opt, optlen, cnt, off, code, type = ICMP_PARAMPROB, forward = 0; */ | |
510 | int opt, optlen, cnt, off, code, type, forward = 0; | |
511 | struct in_addr *sin, dst; | |
512 | typedef u_int32_t n_time; | |
513 | n_time ntime; | |
514 | ||
515 | dst = ip->ip_dst; | |
516 | cp = (u_char *)(ip + 1); | |
517 | cnt = (ip->ip_hl << 2) - sizeof (struct ip); | |
518 | for (; cnt > 0; cnt -= optlen, cp += optlen) { | |
519 | opt = cp[IPOPT_OPTVAL]; | |
520 | if (opt == IPOPT_EOL) | |
521 | break; | |
522 | if (opt == IPOPT_NOP) | |
523 | optlen = 1; | |
524 | else { | |
525 | optlen = cp[IPOPT_OLEN]; | |
526 | if (optlen <= 0 || optlen > cnt) { | |
527 | code = &cp[IPOPT_OLEN] - (u_char *)ip; | |
528 | goto bad; | |
529 | } | |
530 | } | |
531 | switch (opt) { | |
532 | ||
533 | default: | |
534 | break; | |
535 | ||
536 | /* | |
537 | * Source routing with record. | |
538 | * Find interface with current destination address. | |
539 | * If none on this machine then drop if strictly routed, | |
540 | * or do nothing if loosely routed. | |
541 | * Record interface address and bring up next address | |
542 | * component. If strictly routed make sure next | |
543 | * address is on directly accessible net. | |
544 | */ | |
545 | case IPOPT_LSRR: | |
546 | case IPOPT_SSRR: | |
547 | if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) { | |
548 | code = &cp[IPOPT_OFFSET] - (u_char *)ip; | |
549 | goto bad; | |
550 | } | |
551 | ipaddr.sin_addr = ip->ip_dst; | |
552 | ia = (struct in_ifaddr *) | |
553 | ifa_ifwithaddr((struct sockaddr *)&ipaddr); | |
554 | if (ia == 0) { | |
555 | if (opt == IPOPT_SSRR) { | |
556 | type = ICMP_UNREACH; | |
557 | code = ICMP_UNREACH_SRCFAIL; | |
558 | goto bad; | |
559 | } | |
560 | /* | |
561 | * Loose routing, and not at next destination | |
562 | * yet; nothing to do except forward. | |
563 | */ | |
564 | break; | |
565 | } | |
566 | off--; / * 0 origin * / | |
567 | if (off > optlen - sizeof(struct in_addr)) { | |
568 | /* | |
569 | * End of source route. Should be for us. | |
570 | */ | |
571 | save_rte(cp, ip->ip_src); | |
572 | break; | |
573 | } | |
574 | /* | |
575 | * locate outgoing interface | |
576 | */ | |
577 | bcopy((caddr_t)(cp + off), (caddr_t)&ipaddr.sin_addr, | |
578 | sizeof(ipaddr.sin_addr)); | |
579 | if (opt == IPOPT_SSRR) { | |
580 | #define INA struct in_ifaddr * | |
581 | #define SA struct sockaddr * | |
582 | if ((ia = (INA)ifa_ifwithdstaddr((SA)&ipaddr)) == 0) | |
583 | ia = (INA)ifa_ifwithnet((SA)&ipaddr); | |
584 | } else | |
585 | ia = ip_rtaddr(ipaddr.sin_addr); | |
586 | if (ia == 0) { | |
587 | type = ICMP_UNREACH; | |
588 | code = ICMP_UNREACH_SRCFAIL; | |
589 | goto bad; | |
590 | } | |
591 | ip->ip_dst = ipaddr.sin_addr; | |
592 | bcopy((caddr_t)&(IA_SIN(ia)->sin_addr), | |
593 | (caddr_t)(cp + off), sizeof(struct in_addr)); | |
594 | cp[IPOPT_OFFSET] += sizeof(struct in_addr); | |
595 | /* | |
596 | * Let ip_intr's mcast routing check handle mcast pkts | |
597 | */ | |
598 | forward = !IN_MULTICAST(ntohl(ip->ip_dst.s_addr)); | |
599 | break; | |
600 | ||
601 | case IPOPT_RR: | |
602 | if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) { | |
603 | code = &cp[IPOPT_OFFSET] - (u_char *)ip; | |
604 | goto bad; | |
605 | } | |
606 | /* | |
607 | * If no space remains, ignore. | |
608 | */ | |
609 | off--; * 0 origin * | |
610 | if (off > optlen - sizeof(struct in_addr)) | |
611 | break; | |
612 | bcopy((caddr_t)(&ip->ip_dst), (caddr_t)&ipaddr.sin_addr, | |
613 | sizeof(ipaddr.sin_addr)); | |
614 | /* | |
615 | * locate outgoing interface; if we're the destination, | |
616 | * use the incoming interface (should be same). | |
617 | */ | |
618 | if ((ia = (INA)ifa_ifwithaddr((SA)&ipaddr)) == 0 && | |
619 | (ia = ip_rtaddr(ipaddr.sin_addr)) == 0) { | |
620 | type = ICMP_UNREACH; | |
621 | code = ICMP_UNREACH_HOST; | |
622 | goto bad; | |
623 | } | |
624 | bcopy((caddr_t)&(IA_SIN(ia)->sin_addr), | |
625 | (caddr_t)(cp + off), sizeof(struct in_addr)); | |
626 | cp[IPOPT_OFFSET] += sizeof(struct in_addr); | |
627 | break; | |
628 | ||
629 | case IPOPT_TS: | |
630 | code = cp - (u_char *)ip; | |
631 | ipt = (struct ip_timestamp *)cp; | |
632 | if (ipt->ipt_len < 5) | |
633 | goto bad; | |
634 | if (ipt->ipt_ptr > ipt->ipt_len - sizeof (int32_t)) { | |
635 | if (++ipt->ipt_oflw == 0) | |
636 | goto bad; | |
637 | break; | |
638 | } | |
639 | sin = (struct in_addr *)(cp + ipt->ipt_ptr - 1); | |
640 | switch (ipt->ipt_flg) { | |
641 | ||
642 | case IPOPT_TS_TSONLY: | |
643 | break; | |
644 | ||
645 | case IPOPT_TS_TSANDADDR: | |
646 | if (ipt->ipt_ptr + sizeof(n_time) + | |
647 | sizeof(struct in_addr) > ipt->ipt_len) | |
648 | goto bad; | |
649 | ipaddr.sin_addr = dst; | |
650 | ia = (INA)ifaof_ i f p foraddr((SA)&ipaddr, | |
651 | m->m_pkthdr.rcvif); | |
652 | if (ia == 0) | |
653 | continue; | |
654 | bcopy((caddr_t)&IA_SIN(ia)->sin_addr, | |
655 | (caddr_t)sin, sizeof(struct in_addr)); | |
656 | ipt->ipt_ptr += sizeof(struct in_addr); | |
657 | break; | |
658 | ||
659 | case IPOPT_TS_PRESPEC: | |
660 | if (ipt->ipt_ptr + sizeof(n_time) + | |
661 | sizeof(struct in_addr) > ipt->ipt_len) | |
662 | goto bad; | |
663 | bcopy((caddr_t)sin, (caddr_t)&ipaddr.sin_addr, | |
664 | sizeof(struct in_addr)); | |
665 | if (ifa_ifwithaddr((SA)&ipaddr) == 0) | |
666 | continue; | |
667 | ipt->ipt_ptr += sizeof(struct in_addr); | |
668 | break; | |
669 | ||
670 | default: | |
671 | goto bad; | |
672 | } | |
673 | ntime = iptime(); | |
674 | bcopy((caddr_t)&ntime, (caddr_t)cp + ipt->ipt_ptr - 1, | |
675 | sizeof(n_time)); | |
676 | ipt->ipt_ptr += sizeof(n_time); | |
677 | } | |
678 | } | |
679 | if (forward) { | |
680 | ip_forward(m, 1); | |
681 | return (1); | |
682 | } | |
683 | } | |
684 | } | |
685 | return (0); | |
686 | bad: | |
687 | /* ip->ip_len -= ip->ip_hl << 2; XXX icmp_error adds in hdr length */ | |
688 | ||
689 | /* Not yet */ | |
690 | icmp_error(m, type, code, 0, 0); | |
691 | ||
31a60e22 | 692 | STAT(ipstat.ips_badoptions++); |
f0cbd3ec FB |
693 | return (1); |
694 | } | |
695 | ||
696 | #endif /* notdef */ | |
697 | ||
698 | /* | |
699 | * Strip out IP options, at higher | |
700 | * level protocol in the kernel. | |
701 | * Second argument is buffer to which options | |
702 | * will be moved, and return value is their length. | |
703 | * (XXX) should be deleted; last arg currently ignored. | |
704 | */ | |
705 | void | |
706 | ip_stripoptions(m, mopt) | |
707 | register struct mbuf *m; | |
708 | struct mbuf *mopt; | |
709 | { | |
710 | register int i; | |
711 | struct ip *ip = mtod(m, struct ip *); | |
712 | register caddr_t opts; | |
713 | int olen; | |
714 | ||
715 | olen = (ip->ip_hl<<2) - sizeof (struct ip); | |
716 | opts = (caddr_t)(ip + 1); | |
717 | i = m->m_len - (sizeof (struct ip) + olen); | |
718 | memcpy(opts, opts + olen, (unsigned)i); | |
719 | m->m_len -= olen; | |
5fafdf24 | 720 | |
f0cbd3ec FB |
721 | ip->ip_hl = sizeof(struct ip) >> 2; |
722 | } |