| 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. |
| 13 |
* 3. All advertising materials mentioning features or use of this software |
| 14 |
* must display the following acknowledgement: |
| 15 |
* This product includes software developed by the University of |
| 16 |
* California, Berkeley and its contributors. |
| 17 |
* 4. Neither the name of the University nor the names of its contributors |
| 18 |
* may be used to endorse or promote products derived from this software |
| 19 |
* without specific prior written permission. |
| 20 |
* |
| 21 |
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND |
| 22 |
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| 23 |
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| 24 |
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE |
| 25 |
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| 26 |
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
| 27 |
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| 28 |
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
| 29 |
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
| 30 |
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| 31 |
* SUCH DAMAGE. |
| 32 |
* |
| 33 |
* @(#)ip_input.c 8.2 (Berkeley) 1/4/94 |
| 34 |
* ip_input.c,v 1.11 1994/11/16 10:17:08 jkh Exp |
| 35 |
*/ |
| 36 |
|
| 37 |
/* |
| 38 |
* Changes and additions relating to SLiRP are |
| 39 |
* Copyright (c) 1995 Danny Gasparovski. |
| 40 |
* |
| 41 |
* Please read the file COPYRIGHT for the |
| 42 |
* terms and conditions of the copyright. |
| 43 |
*/ |
| 44 |
|
| 45 |
#include <slirp.h> |
| 46 |
#include "ip_icmp.h" |
| 47 |
|
| 48 |
int ip_defttl; |
| 49 |
struct ipstat ipstat; |
| 50 |
struct ipq ipq; |
| 51 |
|
| 52 |
/* |
| 53 |
* IP initialization: fill in IP protocol switch table. |
| 54 |
* All protocols not implemented in kernel go to raw IP protocol handler. |
| 55 |
*/ |
| 56 |
void |
| 57 |
ip_init() |
| 58 |
{ |
| 59 |
ipq.next = ipq.prev = (ipqp_32)&ipq; |
| 60 |
ip_id = tt.tv_sec & 0xffff; |
| 61 |
udp_init(); |
| 62 |
tcp_init(); |
| 63 |
ip_defttl = IPDEFTTL; |
| 64 |
} |
| 65 |
|
| 66 |
/* |
| 67 |
* Ip input routine. Checksum and byte swap header. If fragmented |
| 68 |
* try to reassemble. Process options. Pass to next level. |
| 69 |
*/ |
| 70 |
void |
| 71 |
ip_input(m) |
| 72 |
struct mbuf *m; |
| 73 |
{ |
| 74 |
register struct ip *ip; |
| 75 |
int hlen; |
| 76 |
|
| 77 |
DEBUG_CALL("ip_input"); |
| 78 |
DEBUG_ARG("m = %lx", (long)m); |
| 79 |
DEBUG_ARG("m_len = %d", m->m_len); |
| 80 |
|
| 81 |
ipstat.ips_total++; |
| 82 |
|
| 83 |
if (m->m_len < sizeof (struct ip)) { |
| 84 |
ipstat.ips_toosmall++; |
| 85 |
return; |
| 86 |
} |
| 87 |
|
| 88 |
ip = mtod(m, struct ip *); |
| 89 |
|
| 90 |
if (ip->ip_v != IPVERSION) { |
| 91 |
ipstat.ips_badvers++; |
| 92 |
goto bad; |
| 93 |
} |
| 94 |
|
| 95 |
hlen = ip->ip_hl << 2; |
| 96 |
if (hlen<sizeof(struct ip ) || hlen>m->m_len) {/* min header length */ |
| 97 |
ipstat.ips_badhlen++; /* or packet too short */ |
| 98 |
goto bad; |
| 99 |
} |
| 100 |
|
| 101 |
/* keep ip header intact for ICMP reply |
| 102 |
* ip->ip_sum = cksum(m, hlen); |
| 103 |
* if (ip->ip_sum) { |
| 104 |
*/ |
| 105 |
if(cksum(m,hlen)) { |
| 106 |
ipstat.ips_badsum++; |
| 107 |
goto bad; |
| 108 |
} |
| 109 |
|
| 110 |
/* |
| 111 |
* Convert fields to host representation. |
| 112 |
*/ |
| 113 |
NTOHS(ip->ip_len); |
| 114 |
if (ip->ip_len < hlen) { |
| 115 |
ipstat.ips_badlen++; |
| 116 |
goto bad; |
| 117 |
} |
| 118 |
NTOHS(ip->ip_id); |
| 119 |
NTOHS(ip->ip_off); |
| 120 |
|
| 121 |
/* |
| 122 |
* Check that the amount of data in the buffers |
| 123 |
* is as at least much as the IP header would have us expect. |
| 124 |
* Trim mbufs if longer than we expect. |
| 125 |
* Drop packet if shorter than we expect. |
| 126 |
*/ |
| 127 |
if (m->m_len < ip->ip_len) { |
| 128 |
ipstat.ips_tooshort++; |
| 129 |
goto bad; |
| 130 |
} |
| 131 |
/* Should drop packet if mbuf too long? hmmm... */ |
| 132 |
if (m->m_len > ip->ip_len) |
| 133 |
m_adj(m, ip->ip_len - m->m_len); |
| 134 |
|
| 135 |
/* check ip_ttl for a correct ICMP reply */ |
| 136 |
if(ip->ip_ttl==0 || ip->ip_ttl==1) { |
| 137 |
icmp_error(m, ICMP_TIMXCEED,ICMP_TIMXCEED_INTRANS, 0,"ttl"); |
| 138 |
goto bad; |
| 139 |
} |
| 140 |
|
| 141 |
/* |
| 142 |
* Process options and, if not destined for us, |
| 143 |
* ship it on. ip_dooptions returns 1 when an |
| 144 |
* error was detected (causing an icmp message |
| 145 |
* to be sent and the original packet to be freed). |
| 146 |
*/ |
| 147 |
/* We do no IP options */ |
| 148 |
/* if (hlen > sizeof (struct ip) && ip_dooptions(m)) |
| 149 |
* goto next; |
| 150 |
*/ |
| 151 |
/* |
| 152 |
* If offset or IP_MF are set, must reassemble. |
| 153 |
* Otherwise, nothing need be done. |
| 154 |
* (We could look in the reassembly queue to see |
| 155 |
* if the packet was previously fragmented, |
| 156 |
* but it's not worth the time; just let them time out.) |
| 157 |
* |
| 158 |
* XXX This should fail, don't fragment yet |
| 159 |
*/ |
| 160 |
if (ip->ip_off &~ IP_DF) { |
| 161 |
register struct ipq *fp; |
| 162 |
/* |
| 163 |
* Look for queue of fragments |
| 164 |
* of this datagram. |
| 165 |
*/ |
| 166 |
for (fp = (struct ipq *) ipq.next; fp != &ipq; |
| 167 |
fp = (struct ipq *) fp->next) |
| 168 |
if (ip->ip_id == fp->ipq_id && |
| 169 |
ip->ip_src.s_addr == fp->ipq_src.s_addr && |
| 170 |
ip->ip_dst.s_addr == fp->ipq_dst.s_addr && |
| 171 |
ip->ip_p == fp->ipq_p) |
| 172 |
goto found; |
| 173 |
fp = 0; |
| 174 |
found: |
| 175 |
|
| 176 |
/* |
| 177 |
* Adjust ip_len to not reflect header, |
| 178 |
* set ip_mff if more fragments are expected, |
| 179 |
* convert offset of this to bytes. |
| 180 |
*/ |
| 181 |
ip->ip_len -= hlen; |
| 182 |
if (ip->ip_off & IP_MF) |
| 183 |
((struct ipasfrag *)ip)->ipf_mff |= 1; |
| 184 |
else |
| 185 |
((struct ipasfrag *)ip)->ipf_mff &= ~1; |
| 186 |
|
| 187 |
ip->ip_off <<= 3; |
| 188 |
|
| 189 |
/* |
| 190 |
* If datagram marked as having more fragments |
| 191 |
* or if this is not the first fragment, |
| 192 |
* attempt reassembly; if it succeeds, proceed. |
| 193 |
*/ |
| 194 |
if (((struct ipasfrag *)ip)->ipf_mff & 1 || ip->ip_off) { |
| 195 |
ipstat.ips_fragments++; |
| 196 |
ip = ip_reass((struct ipasfrag *)ip, fp); |
| 197 |
if (ip == 0) |
| 198 |
return; |
| 199 |
ipstat.ips_reassembled++; |
| 200 |
m = dtom(ip); |
| 201 |
} else |
| 202 |
if (fp) |
| 203 |
ip_freef(fp); |
| 204 |
|
| 205 |
} else |
| 206 |
ip->ip_len -= hlen; |
| 207 |
|
| 208 |
/* |
| 209 |
* Switch out to protocol's input routine. |
| 210 |
*/ |
| 211 |
ipstat.ips_delivered++; |
| 212 |
switch (ip->ip_p) { |
| 213 |
case IPPROTO_TCP: |
| 214 |
tcp_input(m, hlen, (struct socket *)NULL); |
| 215 |
break; |
| 216 |
case IPPROTO_UDP: |
| 217 |
udp_input(m, hlen); |
| 218 |
break; |
| 219 |
case IPPROTO_ICMP: |
| 220 |
icmp_input(m, hlen); |
| 221 |
break; |
| 222 |
default: |
| 223 |
ipstat.ips_noproto++; |
| 224 |
m_free(m); |
| 225 |
} |
| 226 |
return; |
| 227 |
bad: |
| 228 |
m_freem(m); |
| 229 |
return; |
| 230 |
} |
| 231 |
|
| 232 |
/* |
| 233 |
* Take incoming datagram fragment and try to |
| 234 |
* reassemble it into whole datagram. If a chain for |
| 235 |
* reassembly of this datagram already exists, then it |
| 236 |
* is given as fp; otherwise have to make a chain. |
| 237 |
*/ |
| 238 |
struct ip * |
| 239 |
ip_reass(ip, fp) |
| 240 |
register struct ipasfrag *ip; |
| 241 |
register struct ipq *fp; |
| 242 |
{ |
| 243 |
register struct mbuf *m = dtom(ip); |
| 244 |
register struct ipasfrag *q; |
| 245 |
int hlen = ip->ip_hl << 2; |
| 246 |
int i, next; |
| 247 |
|
| 248 |
DEBUG_CALL("ip_reass"); |
| 249 |
DEBUG_ARG("ip = %lx", (long)ip); |
| 250 |
DEBUG_ARG("fp = %lx", (long)fp); |
| 251 |
DEBUG_ARG("m = %lx", (long)m); |
| 252 |
|
| 253 |
/* |
| 254 |
* Presence of header sizes in mbufs |
| 255 |
* would confuse code below. |
| 256 |
* Fragment m_data is concatenated. |
| 257 |
*/ |
| 258 |
m->m_data += hlen; |
| 259 |
m->m_len -= hlen; |
| 260 |
|
| 261 |
/* |
| 262 |
* If first fragment to arrive, create a reassembly queue. |
| 263 |
*/ |
| 264 |
if (fp == 0) { |
| 265 |
struct mbuf *t; |
| 266 |
if ((t = m_get()) == NULL) goto dropfrag; |
| 267 |
fp = mtod(t, struct ipq *); |
| 268 |
insque_32(fp, &ipq); |
| 269 |
fp->ipq_ttl = IPFRAGTTL; |
| 270 |
fp->ipq_p = ip->ip_p; |
| 271 |
fp->ipq_id = ip->ip_id; |
| 272 |
fp->ipq_next = fp->ipq_prev = (ipasfragp_32)fp; |
| 273 |
fp->ipq_src = ((struct ip *)ip)->ip_src; |
| 274 |
fp->ipq_dst = ((struct ip *)ip)->ip_dst; |
| 275 |
q = (struct ipasfrag *)fp; |
| 276 |
goto insert; |
| 277 |
} |
| 278 |
|
| 279 |
/* |
| 280 |
* Find a segment which begins after this one does. |
| 281 |
*/ |
| 282 |
for (q = (struct ipasfrag *)fp->ipq_next; q != (struct ipasfrag *)fp; |
| 283 |
q = (struct ipasfrag *)q->ipf_next) |
| 284 |
if (q->ip_off > ip->ip_off) |
| 285 |
break; |
| 286 |
|
| 287 |
/* |
| 288 |
* If there is a preceding segment, it may provide some of |
| 289 |
* our data already. If so, drop the data from the incoming |
| 290 |
* segment. If it provides all of our data, drop us. |
| 291 |
*/ |
| 292 |
if (q->ipf_prev != (ipasfragp_32)fp) { |
| 293 |
i = ((struct ipasfrag *)(q->ipf_prev))->ip_off + |
| 294 |
((struct ipasfrag *)(q->ipf_prev))->ip_len - ip->ip_off; |
| 295 |
if (i > 0) { |
| 296 |
if (i >= ip->ip_len) |
| 297 |
goto dropfrag; |
| 298 |
m_adj(dtom(ip), i); |
| 299 |
ip->ip_off += i; |
| 300 |
ip->ip_len -= i; |
| 301 |
} |
| 302 |
} |
| 303 |
|
| 304 |
/* |
| 305 |
* While we overlap succeeding segments trim them or, |
| 306 |
* if they are completely covered, dequeue them. |
| 307 |
*/ |
| 308 |
while (q != (struct ipasfrag *)fp && ip->ip_off + ip->ip_len > q->ip_off) { |
| 309 |
i = (ip->ip_off + ip->ip_len) - q->ip_off; |
| 310 |
if (i < q->ip_len) { |
| 311 |
q->ip_len -= i; |
| 312 |
q->ip_off += i; |
| 313 |
m_adj(dtom(q), i); |
| 314 |
break; |
| 315 |
} |
| 316 |
q = (struct ipasfrag *) q->ipf_next; |
| 317 |
m_freem(dtom((struct ipasfrag *) q->ipf_prev)); |
| 318 |
ip_deq((struct ipasfrag *) q->ipf_prev); |
| 319 |
} |
| 320 |
|
| 321 |
insert: |
| 322 |
/* |
| 323 |
* Stick new segment in its place; |
| 324 |
* check for complete reassembly. |
| 325 |
*/ |
| 326 |
ip_enq(ip, (struct ipasfrag *) q->ipf_prev); |
| 327 |
next = 0; |
| 328 |
for (q = (struct ipasfrag *) fp->ipq_next; q != (struct ipasfrag *)fp; |
| 329 |
q = (struct ipasfrag *) q->ipf_next) { |
| 330 |
if (q->ip_off != next) |
| 331 |
return (0); |
| 332 |
next += q->ip_len; |
| 333 |
} |
| 334 |
if (((struct ipasfrag *)(q->ipf_prev))->ipf_mff & 1) |
| 335 |
return (0); |
| 336 |
|
| 337 |
/* |
| 338 |
* Reassembly is complete; concatenate fragments. |
| 339 |
*/ |
| 340 |
q = (struct ipasfrag *) fp->ipq_next; |
| 341 |
m = dtom(q); |
| 342 |
|
| 343 |
q = (struct ipasfrag *) q->ipf_next; |
| 344 |
while (q != (struct ipasfrag *)fp) { |
| 345 |
struct mbuf *t; |
| 346 |
t = dtom(q); |
| 347 |
q = (struct ipasfrag *) q->ipf_next; |
| 348 |
m_cat(m, t); |
| 349 |
} |
| 350 |
|
| 351 |
/* |
| 352 |
* Create header for new ip packet by |
| 353 |
* modifying header of first packet; |
| 354 |
* dequeue and discard fragment reassembly header. |
| 355 |
* Make header visible. |
| 356 |
*/ |
| 357 |
ip = (struct ipasfrag *) fp->ipq_next; |
| 358 |
|
| 359 |
/* |
| 360 |
* If the fragments concatenated to an mbuf that's |
| 361 |
* bigger than the total size of the fragment, then and |
| 362 |
* m_ext buffer was alloced. But fp->ipq_next points to |
| 363 |
* the old buffer (in the mbuf), so we must point ip |
| 364 |
* into the new buffer. |
| 365 |
*/ |
| 366 |
if (m->m_flags & M_EXT) { |
| 367 |
int delta; |
| 368 |
delta = (char *)ip - m->m_dat; |
| 369 |
ip = (struct ipasfrag *)(m->m_ext + delta); |
| 370 |
} |
| 371 |
|
| 372 |
/* DEBUG_ARG("ip = %lx", (long)ip); |
| 373 |
* ip=(struct ipasfrag *)m->m_data; */ |
| 374 |
|
| 375 |
ip->ip_len = next; |
| 376 |
ip->ipf_mff &= ~1; |
| 377 |
((struct ip *)ip)->ip_src = fp->ipq_src; |
| 378 |
((struct ip *)ip)->ip_dst = fp->ipq_dst; |
| 379 |
remque_32(fp); |
| 380 |
(void) m_free(dtom(fp)); |
| 381 |
m = dtom(ip); |
| 382 |
m->m_len += (ip->ip_hl << 2); |
| 383 |
m->m_data -= (ip->ip_hl << 2); |
| 384 |
|
| 385 |
return ((struct ip *)ip); |
| 386 |
|
| 387 |
dropfrag: |
| 388 |
ipstat.ips_fragdropped++; |
| 389 |
m_freem(m); |
| 390 |
return (0); |
| 391 |
} |
| 392 |
|
| 393 |
/* |
| 394 |
* Free a fragment reassembly header and all |
| 395 |
* associated datagrams. |
| 396 |
*/ |
| 397 |
void |
| 398 |
ip_freef(fp) |
| 399 |
struct ipq *fp; |
| 400 |
{ |
| 401 |
register struct ipasfrag *q, *p; |
| 402 |
|
| 403 |
for (q = (struct ipasfrag *) fp->ipq_next; q != (struct ipasfrag *)fp; |
| 404 |
q = p) { |
| 405 |
p = (struct ipasfrag *) q->ipf_next; |
| 406 |
ip_deq(q); |
| 407 |
m_freem(dtom(q)); |
| 408 |
} |
| 409 |
remque_32(fp); |
| 410 |
(void) m_free(dtom(fp)); |
| 411 |
} |
| 412 |
|
| 413 |
/* |
| 414 |
* Put an ip fragment on a reassembly chain. |
| 415 |
* Like insque, but pointers in middle of structure. |
| 416 |
*/ |
| 417 |
void |
| 418 |
ip_enq(p, prev) |
| 419 |
register struct ipasfrag *p, *prev; |
| 420 |
{ |
| 421 |
DEBUG_CALL("ip_enq"); |
| 422 |
DEBUG_ARG("prev = %lx", (long)prev); |
| 423 |
p->ipf_prev = (ipasfragp_32) prev; |
| 424 |
p->ipf_next = prev->ipf_next; |
| 425 |
((struct ipasfrag *)(prev->ipf_next))->ipf_prev = (ipasfragp_32) p; |
| 426 |
prev->ipf_next = (ipasfragp_32) p; |
| 427 |
} |
| 428 |
|
| 429 |
/* |
| 430 |
* To ip_enq as remque is to insque. |
| 431 |
*/ |
| 432 |
void |
| 433 |
ip_deq(p) |
| 434 |
register struct ipasfrag *p; |
| 435 |
{ |
| 436 |
((struct ipasfrag *)(p->ipf_prev))->ipf_next = p->ipf_next; |
| 437 |
((struct ipasfrag *)(p->ipf_next))->ipf_prev = p->ipf_prev; |
| 438 |
} |
| 439 |
|
| 440 |
/* |
| 441 |
* IP timer processing; |
| 442 |
* if a timer expires on a reassembly |
| 443 |
* queue, discard it. |
| 444 |
*/ |
| 445 |
void |
| 446 |
ip_slowtimo() |
| 447 |
{ |
| 448 |
register struct ipq *fp; |
| 449 |
|
| 450 |
DEBUG_CALL("ip_slowtimo"); |
| 451 |
|
| 452 |
fp = (struct ipq *) ipq.next; |
| 453 |
if (fp == 0) |
| 454 |
return; |
| 455 |
|
| 456 |
while (fp != &ipq) { |
| 457 |
--fp->ipq_ttl; |
| 458 |
fp = (struct ipq *) fp->next; |
| 459 |
if (((struct ipq *)(fp->prev))->ipq_ttl == 0) { |
| 460 |
ipstat.ips_fragtimeout++; |
| 461 |
ip_freef((struct ipq *) fp->prev); |
| 462 |
} |
| 463 |
} |
| 464 |
} |
| 465 |
|
| 466 |
/* |
| 467 |
* Do option processing on a datagram, |
| 468 |
* possibly discarding it if bad options are encountered, |
| 469 |
* or forwarding it if source-routed. |
| 470 |
* Returns 1 if packet has been forwarded/freed, |
| 471 |
* 0 if the packet should be processed further. |
| 472 |
*/ |
| 473 |
|
| 474 |
#ifdef notdef |
| 475 |
|
| 476 |
int |
| 477 |
ip_dooptions(m) |
| 478 |
struct mbuf *m; |
| 479 |
{ |
| 480 |
register struct ip *ip = mtod(m, struct ip *); |
| 481 |
register u_char *cp; |
| 482 |
register struct ip_timestamp *ipt; |
| 483 |
register struct in_ifaddr *ia; |
| 484 |
/* int opt, optlen, cnt, off, code, type = ICMP_PARAMPROB, forward = 0; */ |
| 485 |
int opt, optlen, cnt, off, code, type, forward = 0; |
| 486 |
struct in_addr *sin, dst; |
| 487 |
typedef u_int32_t n_time; |
| 488 |
n_time ntime; |
| 489 |
|
| 490 |
dst = ip->ip_dst; |
| 491 |
cp = (u_char *)(ip + 1); |
| 492 |
cnt = (ip->ip_hl << 2) - sizeof (struct ip); |
| 493 |
for (; cnt > 0; cnt -= optlen, cp += optlen) { |
| 494 |
opt = cp[IPOPT_OPTVAL]; |
| 495 |
if (opt == IPOPT_EOL) |
| 496 |
break; |
| 497 |
if (opt == IPOPT_NOP) |
| 498 |
optlen = 1; |
| 499 |
else { |
| 500 |
optlen = cp[IPOPT_OLEN]; |
| 501 |
if (optlen <= 0 || optlen > cnt) { |
| 502 |
code = &cp[IPOPT_OLEN] - (u_char *)ip; |
| 503 |
goto bad; |
| 504 |
} |
| 505 |
} |
| 506 |
switch (opt) { |
| 507 |
|
| 508 |
default: |
| 509 |
break; |
| 510 |
|
| 511 |
/* |
| 512 |
* Source routing with record. |
| 513 |
* Find interface with current destination address. |
| 514 |
* If none on this machine then drop if strictly routed, |
| 515 |
* or do nothing if loosely routed. |
| 516 |
* Record interface address and bring up next address |
| 517 |
* component. If strictly routed make sure next |
| 518 |
* address is on directly accessible net. |
| 519 |
*/ |
| 520 |
case IPOPT_LSRR: |
| 521 |
case IPOPT_SSRR: |
| 522 |
if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) { |
| 523 |
code = &cp[IPOPT_OFFSET] - (u_char *)ip; |
| 524 |
goto bad; |
| 525 |
} |
| 526 |
ipaddr.sin_addr = ip->ip_dst; |
| 527 |
ia = (struct in_ifaddr *) |
| 528 |
ifa_ifwithaddr((struct sockaddr *)&ipaddr); |
| 529 |
if (ia == 0) { |
| 530 |
if (opt == IPOPT_SSRR) { |
| 531 |
type = ICMP_UNREACH; |
| 532 |
code = ICMP_UNREACH_SRCFAIL; |
| 533 |
goto bad; |
| 534 |
} |
| 535 |
/* |
| 536 |
* Loose routing, and not at next destination |
| 537 |
* yet; nothing to do except forward. |
| 538 |
*/ |
| 539 |
break; |
| 540 |
} |
| 541 |
off--; / * 0 origin * / |
| 542 |
if (off > optlen - sizeof(struct in_addr)) { |
| 543 |
/* |
| 544 |
* End of source route. Should be for us. |
| 545 |
*/ |
| 546 |
save_rte(cp, ip->ip_src); |
| 547 |
break; |
| 548 |
} |
| 549 |
/* |
| 550 |
* locate outgoing interface |
| 551 |
*/ |
| 552 |
bcopy((caddr_t)(cp + off), (caddr_t)&ipaddr.sin_addr, |
| 553 |
sizeof(ipaddr.sin_addr)); |
| 554 |
if (opt == IPOPT_SSRR) { |
| 555 |
#define INA struct in_ifaddr * |
| 556 |
#define SA struct sockaddr * |
| 557 |
if ((ia = (INA)ifa_ifwithdstaddr((SA)&ipaddr)) == 0) |
| 558 |
ia = (INA)ifa_ifwithnet((SA)&ipaddr); |
| 559 |
} else |
| 560 |
ia = ip_rtaddr(ipaddr.sin_addr); |
| 561 |
if (ia == 0) { |
| 562 |
type = ICMP_UNREACH; |
| 563 |
code = ICMP_UNREACH_SRCFAIL; |
| 564 |
goto bad; |
| 565 |
} |
| 566 |
ip->ip_dst = ipaddr.sin_addr; |
| 567 |
bcopy((caddr_t)&(IA_SIN(ia)->sin_addr), |
| 568 |
(caddr_t)(cp + off), sizeof(struct in_addr)); |
| 569 |
cp[IPOPT_OFFSET] += sizeof(struct in_addr); |
| 570 |
/* |
| 571 |
* Let ip_intr's mcast routing check handle mcast pkts |
| 572 |
*/ |
| 573 |
forward = !IN_MULTICAST(ntohl(ip->ip_dst.s_addr)); |
| 574 |
break; |
| 575 |
|
| 576 |
case IPOPT_RR: |
| 577 |
if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) { |
| 578 |
code = &cp[IPOPT_OFFSET] - (u_char *)ip; |
| 579 |
goto bad; |
| 580 |
} |
| 581 |
/* |
| 582 |
* If no space remains, ignore. |
| 583 |
*/ |
| 584 |
off--; * 0 origin * |
| 585 |
if (off > optlen - sizeof(struct in_addr)) |
| 586 |
break; |
| 587 |
bcopy((caddr_t)(&ip->ip_dst), (caddr_t)&ipaddr.sin_addr, |
| 588 |
sizeof(ipaddr.sin_addr)); |
| 589 |
/* |
| 590 |
* locate outgoing interface; if we're the destination, |
| 591 |
* use the incoming interface (should be same). |
| 592 |
*/ |
| 593 |
if ((ia = (INA)ifa_ifwithaddr((SA)&ipaddr)) == 0 && |
| 594 |
(ia = ip_rtaddr(ipaddr.sin_addr)) == 0) { |
| 595 |
type = ICMP_UNREACH; |
| 596 |
code = ICMP_UNREACH_HOST; |
| 597 |
goto bad; |
| 598 |
} |
| 599 |
bcopy((caddr_t)&(IA_SIN(ia)->sin_addr), |
| 600 |
(caddr_t)(cp + off), sizeof(struct in_addr)); |
| 601 |
cp[IPOPT_OFFSET] += sizeof(struct in_addr); |
| 602 |
break; |
| 603 |
|
| 604 |
case IPOPT_TS: |
| 605 |
code = cp - (u_char *)ip; |
| 606 |
ipt = (struct ip_timestamp *)cp; |
| 607 |
if (ipt->ipt_len < 5) |
| 608 |
goto bad; |
| 609 |
if (ipt->ipt_ptr > ipt->ipt_len - sizeof (int32_t)) { |
| 610 |
if (++ipt->ipt_oflw == 0) |
| 611 |
goto bad; |
| 612 |
break; |
| 613 |
} |
| 614 |
sin = (struct in_addr *)(cp + ipt->ipt_ptr - 1); |
| 615 |
switch (ipt->ipt_flg) { |
| 616 |
|
| 617 |
case IPOPT_TS_TSONLY: |
| 618 |
break; |
| 619 |
|
| 620 |
case IPOPT_TS_TSANDADDR: |
| 621 |
if (ipt->ipt_ptr + sizeof(n_time) + |
| 622 |
sizeof(struct in_addr) > ipt->ipt_len) |
| 623 |
goto bad; |
| 624 |
ipaddr.sin_addr = dst; |
| 625 |
ia = (INA)ifaof_ i f p foraddr((SA)&ipaddr, |
| 626 |
m->m_pkthdr.rcvif); |
| 627 |
if (ia == 0) |
| 628 |
continue; |
| 629 |
bcopy((caddr_t)&IA_SIN(ia)->sin_addr, |
| 630 |
(caddr_t)sin, sizeof(struct in_addr)); |
| 631 |
ipt->ipt_ptr += sizeof(struct in_addr); |
| 632 |
break; |
| 633 |
|
| 634 |
case IPOPT_TS_PRESPEC: |
| 635 |
if (ipt->ipt_ptr + sizeof(n_time) + |
| 636 |
sizeof(struct in_addr) > ipt->ipt_len) |
| 637 |
goto bad; |
| 638 |
bcopy((caddr_t)sin, (caddr_t)&ipaddr.sin_addr, |
| 639 |
sizeof(struct in_addr)); |
| 640 |
if (ifa_ifwithaddr((SA)&ipaddr) == 0) |
| 641 |
continue; |
| 642 |
ipt->ipt_ptr += sizeof(struct in_addr); |
| 643 |
break; |
| 644 |
|
| 645 |
default: |
| 646 |
goto bad; |
| 647 |
} |
| 648 |
ntime = iptime(); |
| 649 |
bcopy((caddr_t)&ntime, (caddr_t)cp + ipt->ipt_ptr - 1, |
| 650 |
sizeof(n_time)); |
| 651 |
ipt->ipt_ptr += sizeof(n_time); |
| 652 |
} |
| 653 |
} |
| 654 |
if (forward) { |
| 655 |
ip_forward(m, 1); |
| 656 |
return (1); |
| 657 |
} |
| 658 |
} |
| 659 |
} |
| 660 |
return (0); |
| 661 |
bad: |
| 662 |
/* ip->ip_len -= ip->ip_hl << 2; XXX icmp_error adds in hdr length */ |
| 663 |
|
| 664 |
/* Not yet */ |
| 665 |
icmp_error(m, type, code, 0, 0); |
| 666 |
|
| 667 |
ipstat.ips_badoptions++; |
| 668 |
return (1); |
| 669 |
} |
| 670 |
|
| 671 |
#endif /* notdef */ |
| 672 |
|
| 673 |
/* |
| 674 |
* Strip out IP options, at higher |
| 675 |
* level protocol in the kernel. |
| 676 |
* Second argument is buffer to which options |
| 677 |
* will be moved, and return value is their length. |
| 678 |
* (XXX) should be deleted; last arg currently ignored. |
| 679 |
*/ |
| 680 |
void |
| 681 |
ip_stripoptions(m, mopt) |
| 682 |
register struct mbuf *m; |
| 683 |
struct mbuf *mopt; |
| 684 |
{ |
| 685 |
register int i; |
| 686 |
struct ip *ip = mtod(m, struct ip *); |
| 687 |
register caddr_t opts; |
| 688 |
int olen; |
| 689 |
|
| 690 |
olen = (ip->ip_hl<<2) - sizeof (struct ip); |
| 691 |
opts = (caddr_t)(ip + 1); |
| 692 |
i = m->m_len - (sizeof (struct ip) + olen); |
| 693 |
memcpy(opts, opts + olen, (unsigned)i); |
| 694 |
m->m_len -= olen; |
| 695 |
|
| 696 |
ip->ip_hl = sizeof(struct ip) >> 2; |
| 697 |
} |
