contrib/ipfilter/ip_lfil.c

   1 /*
   2  * Copyright (C) 1993-2001 by Darren Reed.
   3  *
   4  * See the IPFILTER.LICENCE file for details on licencing.
   5  */
   6 #if !defined(lint)
   7 static const char rcsid[] = "@(#)$Id: ip_lfil.c,v 2.6.2.5 2002/10/03 13:47:19 darrenr Exp $";
   8 #endif
   9
  10 #if defined(KERNEL) && !defined(_KERNEL)
  11 # define        _KERNEL
  12 #endif
  13 #include <sys/errno.h>
  14 #include <sys/types.h>
  15 #include <sys/param.h>
  16 #include <sys/file.h>
  17 #include <sys/ioctl.h>
  18 #include <sys/time.h>
  19 #include <sys/dir.h>
  20 #include <sys/socket.h>
  21 #ifndef _KERNEL
  22 # include <stdio.h>
  23 # include <string.h>
  24 # include <stdlib.h>
  25 # include <ctype.h>
  26 #else
  27 # include <linux/module.h>
  28 #endif
  29
  30 #include <net/if.h>
  31 #include <net/route.h>
  32 #include <netinet/in.h>
  33 #include <netinet/in_systm.h>
  34 #include <netinet/ip.h>
  35 #include <netinet/tcp.h>
  36 #include <netinet/udp.h>
  37 #include <netinet/ip_icmp.h>
  38 #ifndef _KERNEL
  39 # include <syslog.h>
  40 #endif
  41 #include "netinet/ip_compat.h"
  42 #include <netinet/tcpip.h>
  43 #include "netinet/ip_fil.h"
  44 #include "netinet/ip_nat.h"
  45 #include "netinet/ip_proxy.h"
  46 #include "netinet/ip_frag.h"
  47 #include "netinet/ip_state.h"
  48 #include "netinet/ip_auth.h"
  49 #ifdef _KERNEL
  50 #include <net/ip_forward.h>
  51 #endif
  52 #ifndef MIN
  53 #define MIN(a,b)        (((a)<(b))?(a):(b))
  54 #endif
  55
  56
  57 #ifndef _KERNEL
  58 # include "ipt.h"
  59 static  struct  ifnet **ifneta = NULL;
  60 static  int     nifs = 0;
  61 #endif
  62
  63 int     fr_running = 0;
  64 int     ipl_unreach = ICMP_UNREACH_FILTER;
  65 u_long  ipl_frouteok[2] = {0, 0};
  66
  67 static  int     frzerostats __P((caddr_t));
  68 static  void    frsync __P((void));
  69 #if defined(__NetBSD__) || defined(__OpenBSD__)
  70 static  int     frrequest __P((int, u_long, caddr_t, int));
  71 #else
  72 static  int     frrequest __P((int, u_long, caddr_t, int));
  73 #endif
  74 #ifdef  _KERNEL
  75 static  int     (*fr_savep) __P((ip_t *, int, void *, int, mb_t **));
  76 #else
  77 int     ipllog __P((void));
  78 void    init_ifp __P((void));
  79 static int      no_output __P((mb_t *, struct ifnet *));
  80 static int      write_output __P((mb_t *, struct ifnet *));
  81 #endif
  82
  83 #ifdef  _KERNEL
  84
  85 int fr_precheck(struct iphdr *ip, struct device *dev, int out, struct device **ifp)
  86 {
  87         int hlen = ip->ihl << 2;
  88
  89         return fr_check((ip_t *)ip, hlen, dev, out, (mb_t **)ifp);
  90 }
  91
  92
  93 int iplattach()
  94 {
  95         char *defpass;
  96         int s;
  97
  98         if (fr_running || (fr_checkp == fr_precheck)) {
  99                 printk("IP Filter: already initialized\n");
 100                 return EBUSY;
 101         }
 102
 103         fr_running = 1;
 104         bzero((char *)frcache, sizeof(frcache));
 105         bzero((char *)nat_table, sizeof(nat_table));
 106         fr_savep = fr_checkp;
 107         fr_checkp = fr_precheck;
 108
 109 # ifdef IPFILTER_LOG
 110         ipflog_init();
 111 # endif
 112         if (fr_pass & FR_PASS)
 113                 defpass = "pass";
 114         else if (fr_pass & FR_BLOCK)
 115                 defpass = "block";
 116         else
 117                 defpass = "no-match -> block";
 118
 119         printk("IP Filter: initialized.  Default = %s all, Logging = %s\n",
 120                 defpass,
 121 # ifdef IPFILTER_LOG
 122                 "enabled");
 123 # else
 124                 "disabled");
 125 # endif
 126         return 0;
 127 }
 128
 129
 130 /*
 131  * Disable the filter by removing the hooks from the IP input/output
 132  * stream.
 133  */
 134 int ipldetach()
 135 {
 136         int s, i = FR_INQUE|FR_OUTQUE;
 137
 138         if (!fr_running)
 139         {
 140                 printk("IP Filter: not initialized\n");
 141                 return 0;
 142         }
 143
 144         fr_checkp = fr_savep;
 145         i = frflush(IPL_LOGIPF, i);
 146         fr_running = 0;
 147
 148         ipfr_unload();
 149         ip_natunload();
 150         fr_stateunload();
 151         fr_authunload();
 152
 153         printk("IP Filter: unloaded\n");
 154
 155         return 0;
 156 }
 157 #endif /* _KERNEL */
 158
 159
 160 static  int     frzerostats(data)
 161 caddr_t data;
 162 {
 163         struct  friostat        fio;
 164         int error;
 165
 166         bcopy((char *)frstats, (char *)fio.f_st,
 167                 sizeof(struct filterstats) * 2);
 168         fio.f_fin[0] = ipfilter[0][0];
 169         fio.f_fin[1] = ipfilter[0][1];
 170         fio.f_fout[0] = ipfilter[1][0];
 171         fio.f_fout[1] = ipfilter[1][1];
 172         fio.f_acctin[0] = ipacct[0][0];
 173         fio.f_acctin[1] = ipacct[0][1];
 174         fio.f_acctout[0] = ipacct[1][0];
 175         fio.f_acctout[1] = ipacct[1][1];
 176         fio.f_active = fr_active;
 177         fio.f_froute[0] = ipl_frouteok[0];
 178         fio.f_froute[1] = ipl_frouteok[1];
 179         error = IWCOPYPTR((caddr_t)&fio, data, sizeof(fio));
 180         if (!error)
 181                 bzero((char *)frstats, sizeof(*frstats) * 2);
 182         return error;
 183 }
 184
 185
 186 /*
 187  * Filter ioctl interface.
 188  */
 189 #if defined(_KERNEL)
 190 int iplioctl(struct inode *inode, struct file *file, u_int cmd, u_long arg)
 191 {
 192         int s;
 193         caddr_t data = (caddr_t)arg;
 194
 195         int mode = file->f_mode;
 196 #else
 197 int iplioctl(dev_t dev, int cmd, caddr_t data, int mode)
 198 {
 199 #endif
 200         int error = 0, unit = 0, tmp;
 201
 202 #ifdef  _KERNEL
 203         unit = GET_MINOR(inode->i_rdev);
 204         if ((IPL_LOGMAX < unit) || (unit < 0))
 205                 return ENXIO;
 206 #endif
 207
 208         if (unit == IPL_LOGNAT) {
 209                 error = nat_ioctl(data, cmd, mode);
 210                 return error;
 211         }
 212         if (unit == IPL_LOGSTATE) {
 213                 error = fr_state_ioctl(data, cmd, mode);
 214                 return error;
 215         }
 216
 217         switch (cmd) {
 218         case FIONREAD :
 219 #ifdef IPFILTER_LOG
 220                 error = IWCOPY((caddr_t)&iplused[IPL_LOGIPF], data,
 221                                sizeof(iplused[IPL_LOGIPF]));
 222 #endif
 223                 break;
 224 #if !defined(IPFILTER_LKM) && defined(_KERNEL)
 225         case SIOCFRENB :
 226         {
 227                 u_int   enable;
 228
 229                 if (!(mode & FWRITE))
 230                         error = EPERM;
 231                 else {
 232                         error = IRCOPY(data, (caddr_t)&enable, sizeof(enable));
 233                         if (error)
 234                                 break;
 235                         if (enable)
 236                                 error = iplattach();
 237                         else
 238                                 error = ipldetach();
 239                 }
 240                 break;
 241         }
 242 #endif
 243         case SIOCSETFF :
 244                 if (!(mode & FWRITE))
 245                         error = EPERM;
 246                 else
 247                         error = IRCOPY(data, (caddr_t)&fr_flags,
 248                                        sizeof(fr_flags));
 249                 break;
 250         case SIOCGETFF :
 251                 error = IWCOPY((caddr_t)&fr_flags, data, sizeof(fr_flags));
 252                 break;
 253         case SIOCINAFR :
 254         case SIOCRMAFR :
 255         case SIOCADAFR :
 256         case SIOCZRLST :
 257                 if (!(mode & FWRITE))
 258                         error = EPERM;
 259                 else
 260                         error = frrequest(unit, cmd, data, fr_active);
 261                 break;
 262         case SIOCINIFR :
 263         case SIOCRMIFR :
 264         case SIOCADIFR :
 265                 if (!(mode & FWRITE))
 266                         error = EPERM;
 267                 else
 268                         error = frrequest(unit, cmd, data, 1 - fr_active);
 269                 break;
 270         case SIOCSWAPA :
 271                 if (!(mode & FWRITE))
 272                         error = EPERM;
 273                 else {
 274                         bzero((char *)frcache, sizeof(frcache[0]) * 2);
 275                         *(u_int *)data = fr_active;
 276                         fr_active = 1 - fr_active;
 277                 }
 278                 break;
 279         case SIOCGETFS :
 280         {
 281                 struct  friostat        fio;
 282
 283                 bcopy((char *)frstats, (char *)fio.f_st,
 284                         sizeof(struct filterstats) * 2);
 285                 fio.f_fin[0] = ipfilter[0][0];
 286                 fio.f_fin[1] = ipfilter[0][1];
 287                 fio.f_fout[0] = ipfilter[1][0];
 288                 fio.f_fout[1] = ipfilter[1][1];
 289                 fio.f_acctin[0] = ipacct[0][0];
 290                 fio.f_acctin[1] = ipacct[0][1];
 291                 fio.f_acctout[0] = ipacct[1][0];
 292                 fio.f_acctout[1] = ipacct[1][1];
 293                 fio.f_auth = ipauth;
 294                 fio.f_active = fr_active;
 295                 fio.f_froute[0] = ipl_frouteok[0];
 296                 fio.f_froute[1] = ipl_frouteok[1];
 297                 error = IWCOPYPTR((caddr_t)&fio, data, sizeof(fio));
 298                 break;
 299         }
 300         case    SIOCFRZST :
 301                 if (!(mode & FWRITE))
 302                         error = EPERM;
 303                 else
 304                         error = frzerostats(data);
 305                 break;
 306         case    SIOCIPFFL :
 307                 if (!(mode & FWRITE))
 308                         error = EPERM;
 309                 else {
 310                         error = IRCOPY(data, (caddr_t)&tmp, sizeof(tmp));
 311                         if (!error) {
 312                                 tmp = frflush(unit, tmp);
 313                                 error = IWCOPY((caddr_t)&tmp, data,
 314                                                sizeof(tmp));
 315                         }
 316                 }
 317                 break;
 318 #ifdef  IPFILTER_LOG
 319         case    SIOCIPFFB :
 320                 if (!(mode & FWRITE))
 321                         error = EPERM;
 322                 else
 323                         *(int *)data = ipflog_clear(unit);
 324                 break;
 325 #endif /* IPFILTER_LOG */
 326         case SIOCGFRST :
 327                 error = IWCOPYPTR((caddr_t)ipfr_fragstats(), data,
 328                                sizeof(ipfrstat_t));
 329                 break;
 330         case SIOCFRSYN :
 331                 if (!(mode & FWRITE))
 332                         error = EPERM;
 333                 else {
 334 #if defined(_KERNEL) && defined(__sgi)
 335                         ipfsync();
 336 #endif
 337                         frsync();
 338                 }
 339                 break;
 340         default :
 341                 error = EINVAL;
 342                 break;
 343         }
 344         return error;
 345 }
 346
 347
 348 static void frsync()
 349 {
 350 #ifdef _KERNEL
 351         struct device *dev;
 352
 353         for (dev = dev_base; dev; dev = dev->next)
 354                 ip_natsync(dev);
 355 #endif
 356 }
 357
 358
 359 static int frrequest(unit, req, data, set)
 360 int unit;
 361 u_long req;
 362 int set;
 363 caddr_t data;
 364 {
 365         register frentry_t *fp, *f, **fprev;
 366         register frentry_t **ftail;
 367         frentry_t frd;
 368         frdest_t *fdp;
 369         frgroup_t *fg = NULL;
 370         int error = 0, in;
 371         u_int group;
 372
 373         fp = &frd;
 374         error = IRCOPYPTR(data, (caddr_t)fp, sizeof(*fp));
 375         if (error)
 376                 return error;
 377
 378         /*
 379          * Check that the group number does exist and that if a head group
 380          * has been specified, doesn't exist.
 381          */
 382         if (fp->fr_grhead &&
 383             fr_findgroup((u_int)fp->fr_grhead, fp->fr_flags, unit, set, NULL))
 384                 return EEXIST;
 385         if (fp->fr_group &&
 386             !fr_findgroup((u_int)fp->fr_group, fp->fr_flags, unit, set, NULL))
 387                 return ESRCH;
 388
 389         in = (fp->fr_flags & FR_INQUE) ? 0 : 1;
 390
 391         if (unit == IPL_LOGAUTH)
 392                 ftail = fprev = &ipauth;
 393         else if (fp->fr_flags & FR_ACCOUNT)
 394                 ftail = fprev = &ipacct[in][set];
 395         else if (fp->fr_flags & (FR_OUTQUE|FR_INQUE))
 396                 ftail = fprev = &ipfilter[in][set];
 397         else
 398                 return ESRCH;
 399
 400         if ((group = fp->fr_group)) {
 401                 if (!(fg = fr_findgroup(group, fp->fr_flags, unit, set, NULL)))
 402                         return ESRCH;
 403                 ftail = fprev = fg->fg_start;
 404         }
 405
 406         bzero((char *)frcache, sizeof(frcache[0]) * 2);
 407
 408         if (*fp->fr_ifname) {
 409                 fp->fr_ifa = GETUNIT(fp->fr_ifname, fp->fr_ip.fi_v);
 410                 if (!fp->fr_ifa)
 411                         fp->fr_ifa = (void *)-1;
 412         }
 413
 414         fdp = &fp->fr_dif;
 415         fp->fr_flags &= ~FR_DUP;
 416         if (*fdp->fd_ifname) {
 417                 fdp->fd_ifp = GETUNIT(fdp->fd_ifname, fp->fr_ip.fi_v);
 418                 if (!fdp->fd_ifp)
 419                         fdp->fd_ifp = (struct ifnet *)-1;
 420                 else
 421                         fp->fr_flags |= FR_DUP;
 422         }
 423
 424         fdp = &fp->fr_tif;
 425         if (*fdp->fd_ifname) {
 426                 fdp->fd_ifp = GETUNIT(fdp->fd_ifname, fp->fr_ip.fi_v);
 427                 if (!fdp->fd_ifp)
 428                         fdp->fd_ifp = (struct ifnet *)-1;
 429         }
 430
 431         /*
 432          * Look for a matching filter rule, but don't include the next or
 433          * interface pointer in the comparison (fr_next, fr_ifa).
 434          */
 435         for (; (f = *ftail); ftail = &f->fr_next)
 436                 if (bcmp((char *)&f->fr_ip, (char *)&fp->fr_ip,
 437                          FR_CMPSIZ) == 0)
 438                         break;
 439
 440         /*
 441          * If zero'ing statistics, copy current to caller and zero.
 442          */
 443         if (req == SIOCZRLST) {
 444                 if (!f)
 445                         return ESRCH;
 446                 error = IWCOPYPTR((caddr_t)f, data, sizeof(*f));
 447                 if (error)
 448                         return error;
 449                 f->fr_hits = 0;
 450                 f->fr_bytes = 0;
 451                 return 0;
 452         }
 453
 454         if (!f) {
 455                 if (req == SIOCINAFR || req == SIOCINIFR) {
 456                         ftail = fprev;
 457                         if (fp->fr_hits) {
 458                                 while (--fp->fr_hits && (f = *ftail)) {
 459                                         ftail = &f->fr_next;
 460                                 }
 461                         }
 462                 }
 463                 f = NULL;
 464         }
 465
 466         if (req == SIOCRMAFR || req == SIOCRMIFR) {
 467                 if (!f)
 468                         error = ESRCH;
 469                 else {
 470                         if (f->fr_ref > 1)
 471                                 return EBUSY;
 472                         if (fg && fg->fg_head)
 473                                 fg->fg_head->fr_ref--;
 474                         if (unit == IPL_LOGAUTH)
 475                                 return fr_auth_ioctl(data, mode, req, f, ftail);
 476                         if (f->fr_grhead)
 477                                 fr_delgroup((u_int)f->fr_grhead, fp->fr_flags,
 478                                             unit, set);
 479                         fixskip(fprev, f, -1);
 480                         *ftail = f->fr_next;
 481                         KFREE(f);
 482                 }
 483         } else {
 484                 if (f)
 485                         error = EEXIST;
 486                 else {
 487                         if (unit == IPL_LOGAUTH)
 488                                 return fr_auth_ioctl(data, mode, req, f, ftail);
 489                         KMALLOC(f, frentry_t *);
 490                         if (f != NULL) {
 491                                 if (fg && fg->fg_head)
 492                                         fg->fg_head->fr_ref++;
 493                                 bcopy((char *)fp, (char *)f, sizeof(*f));
 494                                 f->fr_ref = 1;
 495                                 f->fr_hits = 0;
 496                                 f->fr_next = *ftail;
 497                                 *ftail = f;
 498                                 if (req == SIOCINIFR || req == SIOCINAFR)
 499                                         fixskip(fprev, f, 1);
 500                                 f->fr_grp = NULL;
 501                                 if ((group = f->fr_grhead))
 502                                         fg = fr_addgroup(group, f, unit, set);
 503                         } else
 504                                 error = ENOMEM;
 505                 }
 506         }
 507         return (error);
 508 }
 509
 510
 511 #ifdef  _KERNEL
 512 /*
 513  * routines below for saving IP headers to buffer
 514  */
 515 int iplopen(struct inode *inode, struct file *file)
 516 {
 517         u_int min = GET_MINOR(inode->i_rdev);
 518
 519         if (IPL_LOGMAX < min)
 520                 min = ENXIO;
 521         else {
 522                 MOD_INC_USE_COUNT;
 523                 min = 0;
 524         }
 525         return min;
 526 }
 527
 528
 529 void iplclose(struct inode *inode, struct file *file)
 530 {
 531         u_int   min = GET_MINOR(inode->i_rdev);
 532
 533         if (IPL_LOGMAX >= min) {
 534                 MOD_DEC_USE_COUNT;
 535         }
 536 }
 537
 538 /*
 539  * iplread/ipllog
 540  * both of these must operate with at least splnet() lest they be
 541  * called during packet processing and cause an inconsistancy to appear in
 542  * the filter lists.
 543  */
 544 int iplread(struct inode *inode, struct file *file, char *buf, int nbytes)
 545 {
 546         struct uio uiob, *uio = &uiob;
 547
 548         uio->uio_buf = buf;
 549         uio->uio_resid = nbytes;
 550 #  ifdef IPFILTER_LOG
 551         return ipflog_read(GET_MINOR(inode->i_rdev), uio);
 552 #  else
 553         return ENXIO;
 554 #  endif
 555 }
 556
 557
 558 /*
 559  * send_reset - this could conceivably be a call to tcp_respond(), but that
 560  * requires a large amount of setting up and isn't any more efficient.
 561  */
 562 int send_reset(ti, ifp)
 563 struct tcpiphdr *ti;
 564 struct ifnet *ifp;
 565 {
 566         tcphdr_t *tcp;
 567         int tlen = 0;
 568         ip_t *ip;
 569         mb_t *m;
 570
 571         if (ti->ti_flags & TH_RST)
 572                 return -1;              /* feedback loop */
 573
 574         m = alloc_skb(sizeof(tcpiphdr_t), GFP_ATOMIC);
 575         if (m == NULL)
 576                 return -1;
 577
 578         if (ti->ti_flags & TH_SYN)
 579                 tlen = 1;
 580
 581         m->dev = ifp;
 582         m->csum = 0;
 583         ip = mtod(m, ip_t *);
 584         m->h.iph = ip;
 585         m->ip_hdr = NULL;
 586         m->m_len = sizeof(tcpiphdr_t);
 587         tcp = (tcphdr_t *)((char *)ip + sizeof(ip_t));
 588         bzero((char *)ip, sizeof(tcpiphdr_t));
 589
 590         ip->ip_v = IPVERSION;
 591         ip->ip_hl = sizeof(ip_t) >> 2;
 592         ip->ip_tos = ((ip_t *)ti)->ip_tos;
 593         ip->ip_p = ((ip_t *)ti)->ip_p;
 594         ip->ip_id = ((ip_t *)ti)->ip_id;
 595         ip->ip_len = htons(sizeof(tcpiphdr_t));
 596         ip->ip_ttl = 127;
 597         ip->ip_src.s_addr = ti->ti_dst.s_addr;
 598         ip->ip_dst.s_addr = ti->ti_src.s_addr;
 599         tcp->th_dport = ti->ti_sport;
 600         tcp->th_sport = ti->ti_dport;
 601         tcp->th_ack = htonl(ntohl(ti->ti_seq) + tlen);
 602         tcp->th_off = sizeof(tcphdr_t) >> 2;
 603         tcp->th_flags = TH_RST|TH_ACK;
 604
 605         ip->ip_sum = 0;
 606         ip->ip_sum = ipf_cksum((u_short *)ip, sizeof(ip_t));
 607         tcp->th_sum = fr_tcpsum(m, ip, tcp);
 608         return ip_forward(m, NULL, IPFWD_NOTTLDEC, ip->ip_dst.s_addr);
 609 }
 610
 611
 612 size_t mbufchainlen(m0)
 613 register mb_t *m0;
 614 {
 615         register size_t len = 0;
 616
 617         for (; m0; m0 = m0->m_next)
 618                 len += m0->m_len;
 619         return len;
 620 }
 621
 622
 623 void ipfr_fastroute(m0, fin, fdp)
 624 mb_t *m0;
 625 fr_info_t *fin;
 626 frdest_t *fdp;
 627 {
 628 #if notyet
 629         register ip_t *ip, *mhip;
 630         register mb_t *m = m0;
 631         register struct route *ro;
 632         struct ifnet *ifp = fdp->fd_ifp;
 633         int len, off, error = 0;
 634         int hlen = fin->fin_hlen;
 635         struct route iproute;
 636         struct sockaddr_in *dst;
 637
 638         ip = mtod(m0, ip_t *);
 639         /*
 640          * Route packet.
 641          */
 642         ro = &iproute;
 643         bzero((caddr_t)ro, sizeof (*ro));
 644         dst = (struct sockaddr_in *)&ro->ro_dst;
 645         dst->sin_family = AF_INET;
 646         dst->sin_addr = fdp->fd_ip.s_addr ? fdp->fd_ip : ip->ip_dst;
 647         /*
 648          * XXX -allocate route here
 649          */
 650         if (!ifp) {
 651                 if (!(fin->fin_fr->fr_flags & FR_FASTROUTE)) {
 652                         error = -2;
 653                         goto bad;
 654                 }
 655                 if (ro->ro_rt == 0 || (ifp = ro->ro_rt->rt_ifp) == 0) {
 656                         if (in_localaddr(ip->ip_dst))
 657                                 error = EHOSTUNREACH;
 658                         else
 659                                 error = ENETUNREACH;
 660                         goto bad;
 661                 }
 662                 if (ro->ro_rt->rt_flags & RTF_GATEWAY)
 663                         dst = (struct sockaddr_in *)&ro->ro_rt->rt_gateway;
 664         }
 665         ro->ro_rt->rt_use++;
 666
 667         /*
 668          * For input packets which are being "fastrouted", they won't
 669          * go back through output filtering and miss their chance to get
 670          * NAT'd.
 671          */
 672         (void) ip_natout(ip, hlen, fin);
 673         if (fin->fin_out)
 674                 ip->ip_sum = 0;
 675         /*
 676          * If small enough for interface, can just send directly.
 677          */
 678         if (ip->ip_len <= ifp->if_mtu) {
 679 # ifndef sparc
 680                 ip->ip_id = htons(ip->ip_id);
 681                 ip->ip_len = htons(ip->ip_len);
 682                 ip->ip_off = htons(ip->ip_off);
 683 # endif
 684                 if (!ip->ip_sum)
 685                         ip->ip_sum = in_cksum(m, hlen);
 686                 error = (*ifp->hard_start_xmit)(m, ifp, m);
 687                 goto done;
 688         }
 689         /*
 690          * Too large for interface; fragment if possible.
 691          * Must be able to put at least 8 bytes per fragment.
 692          */
 693         if (ip->ip_off & IP_DF) {
 694                 error = EMSGSIZE;
 695                 goto bad;
 696         }
 697         len = (ifp->if_mtu - hlen) &~ 7;
 698         if (len < 8) {
 699                 error = EMSGSIZE;
 700                 goto bad;
 701         }
 702
 703     {
 704         int mhlen, firstlen = len;
 705         mb_t **mnext = &m->m_act;
 706
 707         /*
 708          * Loop through length of segment after first fragment,
 709          * make new header and copy data of each part and link onto chain.
 710          */
 711         m0 = m;
 712         mhlen = sizeof (struct ip);
 713         for (off = hlen + len; off < ip->ip_len; off += len) {
 714                 MGET(m, M_DONTWAIT, MT_HEADER);
 715                 if (m == 0) {
 716                         error = ENOBUFS;
 717                         goto bad;
 718                 }
 719                 m->m_data += max_linkhdr;
 720                 mhip = mtod(m, struct ip *);
 721                 bcopy((char *)ip, (char *)mhip, sizeof(*ip));
 722                 if (hlen > sizeof (struct ip)) {
 723                         mhlen = ip_optcopy(ip, mhip) + sizeof (struct ip);
 724                         mhip->ip_hl = mhlen >> 2;
 725                 }
 726                 m->m_len = mhlen;
 727                 mhip->ip_off = ((off - hlen) >> 3) + (ip->ip_off & ~IP_MF);
 728                 if (ip->ip_off & IP_MF)
 729                         mhip->ip_off |= IP_MF;
 730                 if (off + len >= ip->ip_len)
 731                         len = ip->ip_len - off;
 732                 else
 733                         mhip->ip_off |= IP_MF;
 734                 mhip->ip_len = htons((u_short)(len + mhlen));
 735                 m->m_next = m_copy(m0, off, len);
 736                 if (m->m_next == 0) {
 737                         error = ENOBUFS;        /* ??? */
 738                         goto sendorfree;
 739                 }
 740 # ifndef sparc
 741                 mhip->ip_off = htons((u_short)mhip->ip_off);
 742 # endif
 743                 mhip->ip_sum = 0;
 744                 mhip->ip_sum = in_cksum(m, mhlen);
 745                 *mnext = m;
 746                 mnext = &m->m_act;
 747         }
 748         /*
 749          * Update first fragment by trimming what's been copied out
 750          * and updating header, then send each fragment (in order).
 751          */
 752         m_adj(m0, hlen + firstlen - ip->ip_len);
 753         ip->ip_len = htons((u_short)(hlen + firstlen));
 754         ip->ip_off = htons((u_short)(ip->ip_off | IP_MF));
 755         ip->ip_sum = 0;
 756         ip->ip_sum = in_cksum(m0, hlen);
 757 sendorfree:
 758         for (m = m0; m; m = m0) {
 759                 m0 = m->m_act;
 760                 m->m_act = 0;
 761                 if (error == 0)
 762                         error = (*ifp->if_output)(ifp, m,
 763                             (struct sockaddr *)dst);
 764                 else
 765                         m_freem(m);
 766         }
 767     }
 768 done:
 769         if (!error)
 770                 ipl_frouteok[0]++;
 771         else
 772                 ipl_frouteok[1]++;
 773
 774         if (ro->ro_rt) {
 775                 RTFREE(ro->ro_rt);
 776         }
 777         return;
 778 bad:
 779         m_freem(m);
 780         goto done;
 781 # endif
 782 }
 783
 784
 785 /*
 786  * Fake BSD uiomove() call.
 787  */
 788 int uiomove(caddr_t src, size_t ssize, int rw, struct uio *uio)
 789 {
 790         int error;
 791         size_t mv = MIN(ssize, uio->uio_resid);
 792
 793         if (rw == UIO_READ) {
 794                 error = IWCOPY(src, (caddr_t)uio->uio_buf, mv);
 795         } else if (rw == UIO_WRITE) {
 796                 error = IRCOPY((caddr_t)uio->uio_buf, src, mv);
 797         } else
 798                 error = EINVAL;
 799         if (!error) {
 800                 uio->uio_resid -= mv;
 801                 uio->uio_buf += mv;
 802         }
 803         return error;
 804 }
 805
 806 # ifdef IPFILTER_LKM
 807 #  ifndef       IPL_MAJOR
 808 #   define      IPL_MAJOR       95
 809 #  endif
 810
 811 #  ifndef       IPL_NAME
 812 #   define      IPL_NAME        "/dev/ipl"
 813 #  endif
 814
 815 static struct file_operations ipl_fops = {
 816         NULL,           /* lseek */
 817         iplread,        /* read */
 818         NULL,           /* write */
 819         NULL,           /* readdir */
 820         NULL,           /* select */
 821         iplioctl,       /* ioctl */
 822         NULL,           /* mmap */
 823         iplopen,        /* open */
 824         iplclose,       /* release */
 825         NULL,           /* fsync */
 826         NULL,           /* fasync */
 827         NULL,           /* check_media_change */
 828         NULL,           /* revalidate */
 829 };
 830
 831
 832 int init_module(void)
 833 {
 834         int error = 0, major;
 835
 836         if (register_chrdev(IPL_MAJOR, "ipf", &ipl_fops)) {
 837                 printk("ipf: unable to get major number: %d\n", IPL_MAJOR);
 838                 return -EIO;
 839         }
 840
 841         error = iplattach();
 842         if (!error)
 843                 register_symtab(0);
 844         return -error;
 845 }
 846
 847 void cleanup_module(void)
 848 {
 849         unregister_chrdev(IPL_MAJOR, "ipf");
 850         (void) ipldetach();
 851 }
 852 # endif /* IPFILTER_LKM */
 853 #else /* #ifdef _KERNEL */
 854
 855
 856 static int no_output __P((mb_t *m, struct ifnet *ifp))
 857 {
 858         return 0;
 859 }
 860
 861
 862 static int write_output __P((mb_t *m, struct ifnet *ifp))
 863 {
 864         FILE *fp;
 865         char fname[32];
 866         ip_t *ip;
 867
 868         ip = mtod(m, ip_t *);
 869         sprintf(fname, "/tmp/%s", ifp->name);
 870         if ((fp = fopen(fname, "a"))) {
 871                 fwrite((char *)ip, ntohs(ip->ip_len), 1, fp);
 872                 fclose(fp);
 873         }
 874         return 0;
 875 }
 876
 877
 878 struct ifnet *get_unit(name, v)
 879 char *name;
 880 int v;
 881 {
 882         struct ifnet *ifp, **ifa;
 883         char ifname[32], *s;
 884
 885         for (ifa = ifneta; ifa && (ifp = *ifa); ifa++) {
 886                 (void) sprintf(ifname, "%s", ifp->name);
 887                 if (!strcmp(name, ifname))
 888                         return ifp;
 889         }
 890
 891         if (!ifneta) {
 892                 ifneta = (struct ifnet **)malloc(sizeof(ifp) * 2);
 893                 ifneta[1] = NULL;
 894                 ifneta[0] = (struct ifnet *)calloc(1, sizeof(*ifp));
 895                 nifs = 1;
 896         } else {
 897                 nifs++;
 898                 ifneta = (struct ifnet **)realloc(ifneta,
 899                                                   (nifs + 1) * sizeof(*ifa));
 900                 ifneta[nifs] = NULL;
 901                 ifneta[nifs - 1] = (struct ifnet *)malloc(sizeof(*ifp));
 902         }
 903         ifp = ifneta[nifs - 1];
 904
 905         for (s = name; *s && !isdigit(*s); s++)
 906                 ;
 907         if (*s && isdigit(*s)) {
 908                 ifp->name = (char *)malloc(s - name + 1);
 909                 strncpy(ifp->name, name, s - name);
 910                 ifp->name[s - name] = '\0';
 911         } else {
 912                 ifp->name = strdup(name);
 913         }
 914         ifp->hard_start_xmit = no_output;
 915         return ifp;
 916 }
 917
 918
 919
 920 void init_ifp()
 921 {
 922         FILE *fp;
 923         struct ifnet *ifp, **ifa;
 924         char fname[32];
 925
 926         for (ifa = ifneta; ifa && (ifp = *ifa); ifa++) {
 927                 ifp->hard_start_xmit = write_output;
 928                 sprintf(fname, "/tmp/%s", ifp->name);
 929                 if ((fp = fopen(fname, "w")))
 930                         fclose(fp);
 931         }
 932 }
 933
 934
 935 void ipfr_fastroute(ip, fin, fdp)
 936 ip_t *ip;
 937 fr_info_t *fin;
 938 frdest_t *fdp;
 939 {
 940         struct ifnet *ifp = fdp->fd_ifp;
 941
 942         if (!ifp)
 943                 return; /* no routing table out here */
 944
 945         ip->ip_len = htons((u_short)ip->ip_len);
 946         ip->ip_off = htons((u_short)(ip->ip_off | IP_MF));
 947         ip->ip_sum = 0;
 948         (*ifp->hard_start_xmit)((mb_t *)ip, ifp);
 949 }
 950
 951
 952 int ipllog __P((void))
 953 {
 954         verbose("l");
 955         return 0;
 956 }
 957
 958
 959 int send_reset(ip, ifp)
 960 ip_t *ip;
 961 struct ifnet *ifp;
 962 {
 963         verbose("- TCP RST sent\n");
 964         return 0;
 965 }
 966
 967
 968 int icmp_error(ip, ifp)
 969 ip_t *ip;
 970 struct ifnet *ifp;
 971 {
 972         verbose("- TCP RST sent\n");
 973         return 0;
 974 }
 975 #endif /* _KERNEL */