vde-2/slirpvde/ip_input.c

   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 <config.h>
  46 #include <slirp.h>
  47 #include <misc.h>
  48
  49 #include <ip_icmp.h>
  50
  51 int ip_defttl;
  52 struct ipstat ipstat;
  53 struct ipq ipq;
  54
  55 /*
  56  * IP initialization: fill in IP protocol switch table.
  57  * All protocols not implemented in kernel go to raw IP protocol handler.
  58  */
  59 void
  60 ip_init()
  61 {
  62         ipq.next = ipq.prev = (ipqp_32)&ipq;
  63         ip_id = tt.tv_sec & 0xffff;
  64         udp_init();
  65         tcp_init();
  66         ip_defttl = IPDEFTTL;
  67 }
  68
  69 /*
  70  * Ip input routine.  Checksum and byte swap header.  If fragmented
  71  * try to reassemble.  Process options.  Pass to next level.
  72  */
  73 void
  74 ip_input(struct mbuf *m)
  75 {
  76         register struct ip *ip;
  77         int hlen;
  78
  79         DEBUG_CALL("ip_input");
  80         DEBUG_ARG("m = %lx", (long)m);
  81         DEBUG_ARG("m_len = %d", m->m_len);
  82
  83         ipstat.ips_total++;
  84
  85         if (m->m_len < sizeof (struct ip)) {
  86                 ipstat.ips_toosmall++;
  87                 return;
  88         }
  89
  90         ip = mtod(m, struct ip *);
  91
  92         if (ip->ip_v != IPVERSION) {
  93                 ipstat.ips_badvers++;
  94                 //printf("bad version %d \n",ip->ip_v);
  95                 goto bad;
  96         }
  97
  98         hlen = ip->ip_hl << 2;
  99         if (hlen<sizeof(struct ip ) || hlen>m->m_len) {/* min header length */
 100           ipstat.ips_badhlen++;                     /* or packet too short */
 101                 //printf("bad length\n");
 102           goto bad;
 103         }
 104
 105         /* keep ip header intact for ICMP reply
 106          * ip->ip_sum = cksum(m, hlen);
 107          * if (ip->ip_sum) {
 108          */
 109         if(cksum(m,hlen)) {
 110           ipstat.ips_badsum++;
 111                 //printf("bad sum\n");
 112           goto bad;
 113         }
 114
 115         /*
 116          * Convert fields to host representation.
 117          */
 118         NTOHS(ip->ip_len);
 119         if (ip->ip_len < hlen) {
 120                 ipstat.ips_badlen++;
 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) {
 133                 ipstat.ips_tooshort++;
 134                 //printf("bad shortx\n");
 135                 goto bad;
 136         }
 137
 138         /* Should drop packet if mbuf too long? hmmm... */
 139         if (m->m_len > ip->ip_len)
 140            m_adj(m, ip->ip_len - m->m_len);
 141
 142         /* check ip_ttl for a correct ICMP reply */
 143         if(ip->ip_ttl==0 || ip->ip_ttl==1) {
 144           icmp_error(m, ICMP_TIMXCEED,ICMP_TIMXCEED_INTRANS, 0,"ttl");
 145                 //printf("bad ttl\n");
 146           goto bad;
 147         }
 148
 149         /*
 150          * Process options and, if not destined for us,
 151          * ship it on.  ip_dooptions returns 1 when an
 152          * error was detected (causing an icmp message
 153          * to be sent and the original packet to be freed).
 154          */
 155 /* We do no IP options */
 156 /*      if (hlen > sizeof (struct ip) && ip_dooptions(m))
 157  *              goto next;
 158  */
 159         /*
 160          * If offset or IP_MF are set, must reassemble.
 161          * Otherwise, nothing need be done.
 162          * (We could look in the reassembly queue to see
 163          * if the packet was previously fragmented,
 164          * but it's not worth the time; just let them time out.)
 165          *
 166          * XXX This should fail, don't fragment yet
 167          */
 168         if (ip->ip_off &~ IP_DF) {
 169           register struct ipq *fp;
 170                 /*
 171                  * Look for queue of fragments
 172                  * of this datagram.
 173                  */
 174                 for (fp = (struct ipq *) ipq.next; fp != &ipq;
 175                      fp = (struct ipq *) fp->next)
 176                   if (ip->ip_id == fp->ipq_id &&
 177                       ip->ip_src.s_addr == fp->ipq_src.s_addr &&
 178                       ip->ip_dst.s_addr == fp->ipq_dst.s_addr &&
 179                       ip->ip_p == fp->ipq_p)
 180                     goto found;
 181                 fp = 0;
 182         found:
 183
 184                 /*
 185                  * Adjust ip_len to not reflect header,
 186                  * set ip_mff if more fragments are expected,
 187                  * convert offset of this to bytes.
 188                  */
 189                 ip->ip_len -= hlen;
 190                 if (ip->ip_off & IP_MF)
 191                   ((struct ipasfrag *)ip)->ipf_mff |= 1;
 192                 else
 193                   ((struct ipasfrag *)ip)->ipf_mff &= ~1;
 194
 195                 ip->ip_off <<= 3;
 196
 197                 /*
 198                  * If datagram marked as having more fragments
 199                  * or if this is not the first fragment,
 200                  * attempt reassembly; if it succeeds, proceed.
 201                  */
 202                 if (((struct ipasfrag *)ip)->ipf_mff & 1 || ip->ip_off) {
 203                         ipstat.ips_fragments++;
 204                         ip = ip_reass((struct ipasfrag *)ip, fp);
 205                         if (ip == 0)
 206                                 return;
 207                         ipstat.ips_reassembled++;
 208                         m = dtom(ip);
 209                 } else
 210                         if (fp)
 211                            ip_freef(fp);
 212
 213         } else
 214                 ip->ip_len -= hlen;
 215
 216         /*
 217          * Switch out to protocol's input routine.
 218          */
 219         ipstat.ips_delivered++;
 220         switch (ip->ip_p) {
 221          case IPPROTO_TCP:
 222                 tcp_input(m, hlen, (struct socket *)NULL);
 223                 break;
 224          case IPPROTO_UDP:
 225                 udp_input(m, hlen);
 226                 break;
 227          case IPPROTO_ICMP:
 228                 icmp_input(m, hlen);
 229                 break;
 230          default:
 231                 ipstat.ips_noproto++;
 232                 m_free(m);
 233         }
 234         return;
 235 bad:
 236         //printf("bad packet!\n");
 237         m_freem(m);
 238         return;
 239 }
 240
 241 /*
 242  * Take incoming datagram fragment and try to
 243  * reassemble it into whole datagram.  If a chain for
 244  * reassembly of this datagram already exists, then it
 245  * is given as fp; otherwise have to make a chain.
 246  */
 247 struct ip *
 248 ip_reass(ip, fp)
 249         register struct ipasfrag *ip;
 250         register struct ipq *fp;
 251 {
 252         register struct mbuf *m = dtom(ip);
 253         register struct ipasfrag *q;
 254         int hlen = ip->ip_hl << 2;
 255         int i, next;
 256
 257         DEBUG_CALL("ip_reass");
 258         DEBUG_ARG("ip = %lx", (long)ip);
 259         DEBUG_ARG("fp = %lx", (long)fp);
 260         DEBUG_ARG("m = %lx", (long)m);
 261
 262         /*
 263          * Presence of header sizes in mbufs
 264          * would confuse code below.
 265          * Fragment m_data is concatenated.
 266          */
 267         m->m_data += hlen;
 268         m->m_len -= hlen;
 269
 270         /*
 271          * If first fragment to arrive, create a reassembly queue.
 272          */
 273         if (fp == 0) {
 274           struct mbuf *t;
 275           if ((t = m_get()) == NULL) goto dropfrag;
 276           fp = mtod(t, struct ipq *);
 277           insque_32(fp, &ipq);
 278           fp->ipq_ttl = IPFRAGTTL;
 279           fp->ipq_p = ip->ip_p;
 280           fp->ipq_id = ip->ip_id;
 281           fp->ipq_next = fp->ipq_prev = (ipasfragp_32)fp;
 282           fp->ipq_src = ((struct ip *)ip)->ip_src;
 283           fp->ipq_dst = ((struct ip *)ip)->ip_dst;
 284           q = (struct ipasfrag *)fp;
 285           goto insert;
 286         }
 287
 288         /*
 289          * Find a segment which begins after this one does.
 290          */
 291         for (q = (struct ipasfrag *)fp->ipq_next; q != (struct ipasfrag *)fp;
 292             q = (struct ipasfrag *)q->ipf_next)
 293                 if (q->ip_off > ip->ip_off)
 294                         break;
 295
 296         /*
 297          * If there is a preceding segment, it may provide some of
 298          * our data already.  If so, drop the data from the incoming
 299          * segment.  If it provides all of our data, drop us.
 300          */
 301         if (q->ipf_prev != (ipasfragp_32)fp) {
 302                 i = ((struct ipasfrag *)(q->ipf_prev))->ip_off +
 303                   ((struct ipasfrag *)(q->ipf_prev))->ip_len - ip->ip_off;
 304                 if (i > 0) {
 305                         if (i >= ip->ip_len)
 306                                 goto dropfrag;
 307                         m_adj(dtom(ip), i);
 308                         ip->ip_off += i;
 309                         ip->ip_len -= i;
 310                 }
 311         }
 312
 313         /*
 314          * While we overlap succeeding segments trim them or,
 315          * if they are completely covered, dequeue them.
 316          */
 317         while (q != (struct ipasfrag *)fp && ip->ip_off + ip->ip_len > q->ip_off) {
 318                 i = (ip->ip_off + ip->ip_len) - q->ip_off;
 319                 if (i < q->ip_len) {
 320                         q->ip_len -= i;
 321                         q->ip_off += i;
 322                         m_adj(dtom(q), i);
 323                         break;
 324                 }
 325                 q = (struct ipasfrag *) q->ipf_next;
 326                 m_freem(dtom((struct ipasfrag *) q->ipf_prev));
 327                 ip_deq((struct ipasfrag *) q->ipf_prev);
 328         }
 329
 330 insert:
 331         /*
 332          * Stick new segment in its place;
 333          * check for complete reassembly.
 334          */
 335         ip_enq(ip, (struct ipasfrag *) q->ipf_prev);
 336         next = 0;
 337         for (q = (struct ipasfrag *) fp->ipq_next; q != (struct ipasfrag *)fp;
 338              q = (struct ipasfrag *) q->ipf_next) {
 339                 if (q->ip_off != next)
 340                         return (0);
 341                 next += q->ip_len;
 342         }
 343         if (((struct ipasfrag *)(q->ipf_prev))->ipf_mff & 1)
 344                 return (0);
 345
 346         /*
 347          * Reassembly is complete; concatenate fragments.
 348          */
 349         q = (struct ipasfrag *) fp->ipq_next;
 350         m = dtom(q);
 351
 352         q = (struct ipasfrag *) q->ipf_next;
 353         while (q != (struct ipasfrag *)fp) {
 354           struct mbuf *t;
 355           t = dtom(q);
 356           m_cat(m, t);
 357           q = (struct ipasfrag *) q->ipf_next;
 358         }
 359
 360         /*
 361          * Create header for new ip packet by
 362          * modifying header of first packet;
 363          * dequeue and discard fragment reassembly header.
 364          * Make header visible.
 365          */
 366         ip = (struct ipasfrag *) fp->ipq_next;
 367
 368         /*
 369          * If the fragments concatenated to an mbuf that's
 370          * bigger than the total size of the fragment, then and
 371          * m_ext buffer was alloced. But fp->ipq_next points to
 372          * the old buffer (in the mbuf), so we must point ip
 373          * into the new buffer.
 374          */
 375         if (m->m_flags & M_EXT) {
 376           int delta;
 377           delta = (char *)ip - m->m_dat;
 378           ip = (struct ipasfrag *)(m->m_ext + delta);
 379         }
 380
 381         /* DEBUG_ARG("ip = %lx", (long)ip);
 382          * ip=(struct ipasfrag *)m->m_data; */
 383
 384         ip->ip_len = next;
 385         ip->ipf_mff &= ~1;
 386         ((struct ip *)ip)->ip_src = fp->ipq_src;
 387         ((struct ip *)ip)->ip_dst = fp->ipq_dst;
 388         remque_32(fp);
 389         (void) m_free(dtom(fp));
 390         m = dtom(ip);
 391         m->m_len += (ip->ip_hl << 2);
 392         m->m_data -= (ip->ip_hl << 2);
 393
 394         return ((struct ip *)ip);
 395
 396 dropfrag:
 397         ipstat.ips_fragdropped++;
 398         m_freem(m);
 399         return (0);
 400 }
 401
 402 /*
 403  * Free a fragment reassembly header and all
 404  * associated datagrams.
 405  */
 406 void
 407 ip_freef(fp)
 408         struct ipq *fp;
 409 {
 410         register struct ipasfrag *q, *p;
 411
 412         for (q = (struct ipasfrag *) fp->ipq_next; q != (struct ipasfrag *)fp;
 413             q = p) {
 414                 p = (struct ipasfrag *) q->ipf_next;
 415                 ip_deq(q);
 416                 m_freem(dtom(q));
 417         }
 418         remque_32(fp);
 419         (void) m_free(dtom(fp));
 420 }
 421
 422 /*
 423  * Put an ip fragment on a reassembly chain.
 424  * Like insque, but pointers in middle of structure.
 425  */
 426 void
 427 ip_enq(p, prev)
 428         register struct ipasfrag *p, *prev;
 429 {
 430         DEBUG_CALL("ip_enq");
 431         DEBUG_ARG("prev = %lx", (long)prev);
 432         p->ipf_prev = (ipasfragp_32) prev;
 433         p->ipf_next = prev->ipf_next;
 434         ((struct ipasfrag *)(prev->ipf_next))->ipf_prev = (ipasfragp_32) p;
 435         prev->ipf_next = (ipasfragp_32) p;
 436 }
 437
 438 /*
 439  * To ip_enq as remque is to insque.
 440  */
 441 void
 442 ip_deq(p)
 443         register struct ipasfrag *p;
 444 {
 445         ((struct ipasfrag *)(p->ipf_prev))->ipf_next = p->ipf_next;
 446         ((struct ipasfrag *)(p->ipf_next))->ipf_prev = p->ipf_prev;
 447 }
 448
 449 /*
 450  * IP timer processing;
 451  * if a timer expires on a reassembly
 452  * queue, discard it.
 453  */
 454 void
 455 ip_slowtimo()
 456 {
 457         register struct ipq *fp;
 458
 459         DEBUG_CALL("ip_slowtimo");
 460
 461         fp = (struct ipq *) ipq.next;
 462         if (fp == 0)
 463            return;
 464
 465         while (fp != &ipq) {
 466                 --fp->ipq_ttl;
 467                 fp = (struct ipq *) fp->next;
 468                 if (((struct ipq *)(fp->prev))->ipq_ttl == 0) {
 469                         ipstat.ips_fragtimeout++;
 470                         ip_freef((struct ipq *) fp->prev);
 471                 }
 472         }
 473 }
 474
 475 /*
 476  * Do option processing on a datagram,
 477  * possibly discarding it if bad options are encountered,
 478  * or forwarding it if source-routed.
 479  * Returns 1 if packet has been forwarded/freed,
 480  * 0 if the packet should be processed further.
 481  */
 482
 483 #ifdef notdef
 484
 485 int
 486 ip_dooptions(m)
 487         struct mbuf *m;
 488 {
 489         register struct ip *ip = mtod(m, struct ip *);
 490         register u_char *cp;
 491         register struct ip_timestamp *ipt;
 492         register struct in_ifaddr *ia;
 493 /*      int opt, optlen, cnt, off, code, type = ICMP_PARAMPROB, forward = 0; */
 494         int opt, optlen, cnt, off, code, type, forward = 0;
 495         struct in_addr *sin, dst;
 496 typedef u_int32_t n_time;
 497         n_time ntime;
 498
 499         dst = ip->ip_dst;
 500         cp = (u_char *)(ip + 1);
 501         cnt = (ip->ip_hl << 2) - sizeof (struct ip);
 502         for (; cnt > 0; cnt -= optlen, cp += optlen) {
 503                 opt = cp[IPOPT_OPTVAL];
 504                 if (opt == IPOPT_EOL)
 505                         break;
 506                 if (opt == IPOPT_NOP)
 507                         optlen = 1;
 508                 else {
 509                         optlen = cp[IPOPT_OLEN];
 510                         if (optlen <= 0 || optlen > cnt) {
 511                                 code = &cp[IPOPT_OLEN] - (u_char *)ip;
 512                                 goto bad;
 513                         }
 514                 }
 515                 switch (opt) {
 516
 517                 default:
 518                         break;
 519
 520                 /*
 521                  * Source routing with record.
 522                  * Find interface with current destination address.
 523                  * If none on this machine then drop if strictly routed,
 524                  * or do nothing if loosely routed.
 525                  * Record interface address and bring up next address
 526                  * component.  If strictly routed make sure next
 527                  * address is on directly accessible net.
 528                  */
 529                 case IPOPT_LSRR:
 530                 case IPOPT_SSRR:
 531                         if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) {
 532                                 code = &cp[IPOPT_OFFSET] - (u_char *)ip;
 533                                 goto bad;
 534                         }
 535                         ipaddr.sin_addr = ip->ip_dst;
 536                         ia = (struct in_ifaddr *)
 537                                 ifa_ifwithaddr((struct sockaddr *)&ipaddr);
 538                         if (ia == 0) {
 539                                 if (opt == IPOPT_SSRR) {
 540                                         type = ICMP_UNREACH;
 541                                         code = ICMP_UNREACH_SRCFAIL;
 542                                         goto bad;
 543                                 }
 544                                 /*
 545                                  * Loose routing, and not at next destination
 546                                  * yet; nothing to do except forward.
 547                                  */
 548                                 break;
 549                         }
 550                         off--;                  / * 0 origin *  /
 551                         if (off > optlen - sizeof(struct in_addr)) {
 552                                 /*
 553                                  * End of source route.  Should be for us.
 554                                  */
 555                                 save_rte(cp, ip->ip_src);
 556                                 break;
 557                         }
 558                         /*
 559                          * locate outgoing interface
 560                          */
 561                         bcopy((caddr_t)(cp + off), (caddr_t)&ipaddr.sin_addr,
 562                             sizeof(ipaddr.sin_addr));
 563                         if (opt == IPOPT_SSRR) {
 564 #define INA     struct in_ifaddr *
 565 #define SA      struct sockaddr *
 566                             if ((ia = (INA)ifa_ifwithdstaddr((SA)&ipaddr)) == 0)
 567                                 ia = (INA)ifa_ifwithnet((SA)&ipaddr);
 568                         } else
 569                                 ia = ip_rtaddr(ipaddr.sin_addr);
 570                         if (ia == 0) {
 571                                 type = ICMP_UNREACH;
 572                                 code = ICMP_UNREACH_SRCFAIL;
 573                                 goto bad;
 574                         }
 575                         ip->ip_dst = ipaddr.sin_addr;
 576                         bcopy((caddr_t)&(IA_SIN(ia)->sin_addr),
 577                             (caddr_t)(cp + off), sizeof(struct in_addr));
 578                         cp[IPOPT_OFFSET] += sizeof(struct in_addr);
 579                         /*
 580                          * Let ip_intr's mcast routing check handle mcast pkts
 581                          */
 582                         forward = !IN_MULTICAST(ntohl(ip->ip_dst.s_addr));
 583                         break;
 584
 585                 case IPOPT_RR:
 586                         if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) {
 587                                 code = &cp[IPOPT_OFFSET] - (u_char *)ip;
 588                                 goto bad;
 589                         }
 590                         /*
 591                          * If no space remains, ignore.
 592                          */
 593                         off--;                   * 0 origin *
 594                         if (off > optlen - sizeof(struct in_addr))
 595                                 break;
 596                         bcopy((caddr_t)(&ip->ip_dst), (caddr_t)&ipaddr.sin_addr,
 597                             sizeof(ipaddr.sin_addr));
 598                         /*
 599                          * locate outgoing interface; if we're the destination,
 600                          * use the incoming interface (should be same).
 601                          */
 602                         if ((ia = (INA)ifa_ifwithaddr((SA)&ipaddr)) == 0 &&
 603                             (ia = ip_rtaddr(ipaddr.sin_addr)) == 0) {
 604                                 type = ICMP_UNREACH;
 605                                 code = ICMP_UNREACH_HOST;
 606                                 goto bad;
 607                         }
 608                         bcopy((caddr_t)&(IA_SIN(ia)->sin_addr),
 609                             (caddr_t)(cp + off), sizeof(struct in_addr));
 610                         cp[IPOPT_OFFSET] += sizeof(struct in_addr);
 611                         break;
 612
 613                 case IPOPT_TS:
 614                         code = cp - (u_char *)ip;
 615                         ipt = (struct ip_timestamp *)cp;
 616                         if (ipt->ipt_len < 5)
 617                                 goto bad;
 618                         if (ipt->ipt_ptr > ipt->ipt_len - sizeof (int32_t)) {
 619                                 if (++ipt->ipt_oflw == 0)
 620                                         goto bad;
 621                                 break;
 622                         }
 623                         sin = (struct in_addr *)(cp + ipt->ipt_ptr - 1);
 624                         switch (ipt->ipt_flg) {
 625
 626                         case IPOPT_TS_TSONLY:
 627                                 break;
 628
 629                         case IPOPT_TS_TSANDADDR:
 630                                 if (ipt->ipt_ptr + sizeof(n_time) +
 631                                     sizeof(struct in_addr) > ipt->ipt_len)
 632                                         goto bad;
 633                                 ipaddr.sin_addr = dst;
 634                                 ia = (INA)ifaof_ i f p foraddr((SA)&ipaddr,
 635                                                             m->m_pkthdr.rcvif);
 636                                 if (ia == 0)
 637                                         continue;
 638                                 bcopy((caddr_t)&IA_SIN(ia)->sin_addr,
 639                                     (caddr_t)sin, sizeof(struct in_addr));
 640                                 ipt->ipt_ptr += sizeof(struct in_addr);
 641                                 break;
 642
 643                         case IPOPT_TS_PRESPEC:
 644                                 if (ipt->ipt_ptr + sizeof(n_time) +
 645                                     sizeof(struct in_addr) > ipt->ipt_len)
 646                                         goto bad;
 647                                 bcopy((caddr_t)sin, (caddr_t)&ipaddr.sin_addr,
 648                                     sizeof(struct in_addr));
 649                                 if (ifa_ifwithaddr((SA)&ipaddr) == 0)
 650                                         continue;
 651                                 ipt->ipt_ptr += sizeof(struct in_addr);
 652                                 break;
 653
 654                         default:
 655                                 goto bad;
 656                         }
 657                         ntime = iptime();
 658                         bcopy((caddr_t)&ntime, (caddr_t)cp + ipt->ipt_ptr - 1,
 659                             sizeof(n_time));
 660                         ipt->ipt_ptr += sizeof(n_time);
 661                 }
 662         }
 663         if (forward) {
 664                 ip_forward(m, 1);
 665                 return (1);
 666         }
 667                 }
 668         }
 669         return (0);
 670 bad:
 671         /* ip->ip_len -= ip->ip_hl << 2;   XXX icmp_error adds in hdr length */
 672
 673 /* Not yet */
 674         icmp_error(m, type, code, 0, 0);
 675
 676         ipstat.ips_badoptions++;
 677         return (1);
 678 }
 679
 680 #endif /* notdef */
 681
 682 /*
 683  * Strip out IP options, at higher
 684  * level protocol in the kernel.
 685  * Second argument is buffer to which options
 686  * will be moved, and return value is their length.
 687  * (XXX) should be deleted; last arg currently ignored.
 688  */
 689 void
 690 ip_stripoptions(m, mopt)
 691         register struct mbuf *m;
 692         struct mbuf *mopt;
 693 {
 694         register int i;
 695         struct ip *ip = mtod(m, struct ip *);
 696         register caddr_t opts;
 697         int olen;
 698
 699         olen = (ip->ip_hl<<2) - sizeof (struct ip);
 700         opts = (caddr_t)(ip + 1);
 701         i = m->m_len - (sizeof (struct ip) + olen);
 702         memcpy(opts, opts  + olen, (unsigned)i);
 703         m->m_len -= olen;
 704
 705         ip->ip_hl = sizeof(struct ip) >> 2;
 706 }