sys/contrib/ipfilter/netinet/ip_auth.c

   1 /*
   2  * Copyright (C) 1998-2001 by Darren Reed & Guido van Rooij.
   3  *
   4  * See the IPFILTER.LICENCE file for details on licencing.
   5  *
   6  * @(#)$Id: ip_auth.c,v 2.11.2.20 2002/06/04 14:40:42 darrenr Exp $
   7  * $FreeBSD: src/sys/contrib/ipfilter/netinet/ip_auth.c,v 1.21.2.7 2003/03/01 03:55:54 darrenr Exp $
   8  * $DragonFly: src/sys/contrib/ipfilter/netinet/ip_auth.c,v 1.6 2004/02/12 22:35:47 joerg Exp $
   9  */
  10 #if defined(__sgi) && (IRIX > 602)
  11 # include <sys/ptimers.h>
  12 #endif
  13 #include <sys/errno.h>
  14 #include <sys/types.h>
  15 #include <sys/param.h>
  16 #include <sys/time.h>
  17 #include <sys/file.h>
  18 #if !defined(_KERNEL) && !defined(KERNEL)
  19 # include <stdio.h>
  20 # include <stdlib.h>
  21 # include <string.h>
  22 #endif
  23 #if (defined(KERNEL) || defined(_KERNEL)) && (defined(__DragonFly__) || __FreeBSD_version >= 220000)
  24 # include <sys/filio.h>
  25 # include <sys/fcntl.h>
  26 #else
  27 # include <sys/ioctl.h>
  28 #endif
  29 #ifndef linux
  30 # include <sys/protosw.h>
  31 #endif
  32 #include <sys/socket.h>
  33 #if (defined(_KERNEL) || defined(KERNEL)) && !defined(linux)
  34 # include <sys/systm.h>
  35 #endif
  36 #if !defined(__SVR4) && !defined(__svr4__)
  37 # ifndef linux
  38 #  include <sys/mbuf.h>
  39 # endif
  40 #else
  41 # include <sys/filio.h>
  42 # include <sys/byteorder.h>
  43 # ifdef _KERNEL
  44 #  include <sys/dditypes.h>
  45 # endif
  46 # include <sys/stream.h>
  47 # include <sys/kmem.h>
  48 #endif
  49 #if defined(__DragonFly__) || (_BSDI_VERSION >= 199802) || (__FreeBSD_version >= 400000)
  50 # include <sys/queue.h>
  51 #endif
  52 #if defined(__NetBSD__) || defined(__OpenBSD__) || defined(bsdi)
  53 # include <machine/cpu.h>
  54 #endif
  55 #include <net/if.h>
  56 #ifdef sun
  57 # include <net/af.h>
  58 #endif
  59 #include <net/route.h>
  60 #include <netinet/in.h>
  61 #include <netinet/in_systm.h>
  62 #include <netinet/ip.h>
  63 #ifndef KERNEL
  64 # define        KERNEL
  65 # define        NOT_KERNEL
  66 #endif
  67 #ifndef linux
  68 # include <netinet/ip_var.h>
  69 #endif
  70 #ifdef  NOT_KERNEL
  71 # undef KERNEL
  72 #endif
  73 #ifdef __sgi
  74 # ifdef IFF_DRVRLOCK /* IRIX6 */
  75 #  include <sys/hashing.h>
  76 # endif
  77 #endif
  78 #include <netinet/tcp.h>
  79 #if defined(__sgi) && !defined(IFF_DRVRLOCK) /* IRIX < 6 */
  80 extern struct ifqueue   ipintrq;                /* ip packet input queue */
  81 #else
  82 # ifndef linux
  83 #  if defined(__DragonFly__) || __FreeBSD_version >= 300000
  84 #   include <net/if_var.h>
  85 #  endif
  86 #  include <netinet/in_var.h>
  87 #  include <netinet/tcp_fsm.h>
  88 # endif
  89 #endif
  90 #include <netinet/udp.h>
  91 #include <netinet/ip_icmp.h>
  92 #include "ip_compat.h"
  93 #include <netinet/tcpip.h>
  94 #include "ip_fil.h"
  95 #include "ip_auth.h"
  96 #if !SOLARIS && !defined(linux)
  97 # include <net/netisr.h>
  98 # if defined(__DragonFly__) || defined(__FreeBSD__)
  99 #  include <machine/cpufunc.h>
 100 # endif
 101 #endif
 102 #if defined(__DragonFly__) || (__FreeBSD_version >= 300000)
 103 # include <sys/malloc.h>
 104 # if (defined(_KERNEL) || defined(KERNEL)) && !defined(IPFILTER_LKM)
 105 #  include <sys/libkern.h>
 106 #  include <sys/systm.h>
 107 # endif
 108 #endif
 109
 110 #if (SOLARIS || defined(__sgi)) && defined(_KERNEL)
 111 extern KRWLOCK_T ipf_auth, ipf_mutex;
 112 extern kmutex_t ipf_authmx;
 113 # if SOLARIS
 114 extern kcondvar_t ipfauthwait;
 115 # endif
 116 #endif
 117 #ifdef linux
 118 static struct wait_queue *ipfauthwait = NULL;
 119 #endif
 120
 121 int     fr_authsize = FR_NUMAUTH;
 122 int     fr_authused = 0;
 123 int     fr_defaultauthage = 600;
 124 int     fr_auth_lock = 0;
 125 fr_authstat_t   fr_authstats;
 126 static frauth_t fr_auth[FR_NUMAUTH];
 127 mb_t    *fr_authpkts[FR_NUMAUTH];
 128 static int      fr_authstart = 0, fr_authend = 0, fr_authnext = 0;
 129 static frauthent_t      *fae_list = NULL;
 130 frentry_t       *ipauth = NULL,
 131                 *fr_authlist = NULL;
 132
 133
 134 /*
 135  * Check if a packet has authorization.  If the packet is found to match an
 136  * authorization result and that would result in a feedback loop (i.e. it
 137  * will end up returning FR_AUTH) then return FR_BLOCK instead.
 138  */
 139 u_32_t fr_checkauth(ip, fin)
 140 ip_t *ip;
 141 fr_info_t *fin;
 142 {
 143         u_short id = ip->ip_id;
 144         frentry_t *fr;
 145         frauth_t *fra;
 146         u_32_t pass;
 147         int i;
 148
 149         if (fr_auth_lock || !fr_authused)
 150                 return 0;
 151
 152         READ_ENTER(&ipf_auth);
 153         for (i = fr_authstart; i != fr_authend; ) {
 154                 /*
 155                  * index becomes -2 only after an SIOCAUTHW.  Check this in
 156                  * case the same packet gets sent again and it hasn't yet been
 157                  * auth'd.
 158                  */
 159                 fra = fr_auth + i;
 160                 if ((fra->fra_index == -2) && (id == fra->fra_info.fin_id) &&
 161                     !bcmp((char *)fin, (char *)&fra->fra_info, FI_CSIZE)) {
 162                         /*
 163                          * Avoid feedback loop.
 164                          */
 165                         if (!(pass = fra->fra_pass) || (pass & FR_AUTH))
 166                                 pass = FR_BLOCK;
 167                         /*
 168                          * Create a dummy rule for the stateful checking to
 169                          * use and return.  Zero out any values we don't
 170                          * trust from userland!
 171                          */
 172                         if ((pass & FR_KEEPSTATE) || ((pass & FR_KEEPFRAG) &&
 173                              (fin->fin_fi.fi_fl & FI_FRAG))) {
 174                                 KMALLOC(fr, frentry_t *);
 175                                 if (fr) {
 176                                         bcopy((char *)fra->fra_info.fin_fr,
 177                                               fr, sizeof(*fr));
 178                                         fr->fr_grp = NULL;
 179                                         fr->fr_ifa = fin->fin_ifp;
 180                                         fr->fr_func = NULL;
 181                                         fr->fr_ref = 1;
 182                                         fr->fr_flags = pass;
 183 #if BSD >= 199306
 184                                         fr->fr_oifa = NULL;
 185 #endif
 186                                 }
 187                         } else
 188                                 fr = fra->fra_info.fin_fr;
 189                         fin->fin_fr = fr;
 190                         RWLOCK_EXIT(&ipf_auth);
 191                         WRITE_ENTER(&ipf_auth);
 192                         if (fr && fr != fra->fra_info.fin_fr) {
 193                                 fr->fr_next = fr_authlist;
 194                                 fr_authlist = fr;
 195                         }
 196                         fr_authstats.fas_hits++;
 197                         fra->fra_index = -1;
 198                         fr_authused--;
 199                         if (i == fr_authstart) {
 200                                 while (fra->fra_index == -1) {
 201                                         i++;
 202                                         fra++;
 203                                         if (i == FR_NUMAUTH) {
 204                                                 i = 0;
 205                                                 fra = fr_auth;
 206                                         }
 207                                         fr_authstart = i;
 208                                         if (i == fr_authend)
 209                                                 break;
 210                                 }
 211                                 if (fr_authstart == fr_authend) {
 212                                         fr_authnext = 0;
 213                                         fr_authstart = fr_authend = 0;
 214                                 }
 215                         }
 216                         RWLOCK_EXIT(&ipf_auth);
 217                         return pass;
 218                 }
 219                 i++;
 220                 if (i == FR_NUMAUTH)
 221                         i = 0;
 222         }
 223         fr_authstats.fas_miss++;
 224         RWLOCK_EXIT(&ipf_auth);
 225         return 0;
 226 }
 227
 228
 229 /*
 230  * Check if we have room in the auth array to hold details for another packet.
 231  * If we do, store it and wake up any user programs which are waiting to
 232  * hear about these events.
 233  */
 234 int fr_newauth(m, fin, ip)
 235 mb_t *m;
 236 fr_info_t *fin;
 237 ip_t *ip;
 238 {
 239 #if defined(_KERNEL) && SOLARIS
 240         qif_t *qif = fin->fin_qif;
 241 #endif
 242         frauth_t *fra;
 243         int i;
 244
 245         if (fr_auth_lock)
 246                 return 0;
 247
 248         WRITE_ENTER(&ipf_auth);
 249         if (fr_authstart > fr_authend) {
 250                 fr_authstats.fas_nospace++;
 251                 RWLOCK_EXIT(&ipf_auth);
 252                 return 0;
 253         } else {
 254                 if (fr_authused == FR_NUMAUTH) {
 255                         fr_authstats.fas_nospace++;
 256                         RWLOCK_EXIT(&ipf_auth);
 257                         return 0;
 258                 }
 259         }
 260
 261         fr_authstats.fas_added++;
 262         fr_authused++;
 263         i = fr_authend++;
 264         if (fr_authend == FR_NUMAUTH)
 265                 fr_authend = 0;
 266         RWLOCK_EXIT(&ipf_auth);
 267         fra = fr_auth + i;
 268         fra->fra_index = i;
 269         fra->fra_pass = 0;
 270         fra->fra_age = fr_defaultauthage;
 271         bcopy((char *)fin, (char *)&fra->fra_info, sizeof(*fin));
 272 #if SOLARIS && defined(_KERNEL)
 273 # if !defined(sparc)
 274         /*
 275          * No need to copyback here as we want to undo the changes, not keep
 276          * them.
 277          */
 278         if ((ip == (ip_t *)m->b_rptr) && (ip->ip_v == 4))
 279         {
 280                 u_short bo;
 281
 282                 bo = ip->ip_len;
 283                 ip->ip_len = htons(bo);
 284                 bo = ip->ip_off;
 285                 ip->ip_off = htons(bo);
 286         }
 287 # endif
 288         m->b_rptr -= qif->qf_off;
 289         fr_authpkts[i] = *(mblk_t **)fin->fin_mp;
 290         fra->fra_q = qif->qf_q;
 291         cv_signal(&ipfauthwait);
 292 #else
 293 # if defined(BSD) && !defined(sparc) && (BSD >= 199306)
 294         if (fin->fin_out == 0) {
 295                 ip->ip_len = htons(ip->ip_len);
 296                 ip->ip_off = htons(ip->ip_off);
 297         }
 298 # endif
 299         fr_authpkts[i] = m;
 300         WAKEUP(&fr_authnext);
 301 #endif
 302         return 1;
 303 }
 304
 305
 306 int fr_auth_ioctl(data, mode, cmd)
 307 caddr_t data;
 308 int mode;
 309 #if defined(__DragonFly__) || defined(__NetBSD__) || defined(__OpenBSD__) || (__FreeBSD_version >= 300003)
 310 u_long cmd;
 311 #else
 312 int cmd;
 313 #endif
 314 {
 315         mb_t *m;
 316 #if defined(_KERNEL) && !SOLARIS
 317 #if !defined(__DragonFly__) && !defined(__FreeBSD__)
 318         struct ifqueue *ifq;
 319 #endif
 320         int s;
 321 #endif
 322         frauth_t auth, *au = &auth, *fra;
 323         int i, error = 0;
 324
 325         switch (cmd)
 326         {
 327         case SIOCSTLCK :
 328                 if (!(mode & FWRITE)) {
 329                         error = EPERM;
 330                         break;
 331                 }
 332                 error = fr_lock(data, &fr_auth_lock);
 333                 break;
 334         case SIOCINIFR :
 335         case SIOCRMIFR :
 336         case SIOCADIFR :
 337                 error = EINVAL;
 338                 break;
 339         case SIOCINAFR :
 340                 error = EINVAL;
 341                 break;
 342         case SIOCRMAFR :
 343         case SIOCADAFR :
 344                 /* These commands go via request to fr_preauthcmd */
 345                 error = EINVAL;
 346                 break;
 347         case SIOCATHST:
 348                 fr_authstats.fas_faelist = fae_list;
 349                 error = IWCOPYPTR((char *)&fr_authstats, data,
 350                                    sizeof(fr_authstats));
 351                 break;
 352         case SIOCAUTHW:
 353                 if (!(mode & FWRITE)) {
 354                         error = EPERM;
 355                         break;
 356                 }
 357 fr_authioctlloop:
 358                 READ_ENTER(&ipf_auth);
 359                 if ((fr_authnext != fr_authend) && fr_authpkts[fr_authnext]) {
 360                         error = IWCOPYPTR((char *)&fr_auth[fr_authnext], data,
 361                                           sizeof(frauth_t));
 362                         RWLOCK_EXIT(&ipf_auth);
 363                         if (error)
 364                                 break;
 365                         WRITE_ENTER(&ipf_auth);
 366                         SPL_NET(s);
 367                         fr_authnext++;
 368                         if (fr_authnext == FR_NUMAUTH)
 369                                 fr_authnext = 0;
 370                         SPL_X(s);
 371                         RWLOCK_EXIT(&ipf_auth);
 372                         return 0;
 373                 }
 374                 RWLOCK_EXIT(&ipf_auth);
 375 #ifdef  _KERNEL
 376 # if    SOLARIS
 377                 mutex_enter(&ipf_authmx);
 378                 if (!cv_wait_sig(&ipfauthwait, &ipf_authmx)) {
 379                         mutex_exit(&ipf_authmx);
 380                         return EINTR;
 381                 }
 382                 mutex_exit(&ipf_authmx);
 383 # else
 384                 error = SLEEP(&fr_authnext, "fr_authnext");
 385 # endif
 386 #endif
 387                 if (!error)
 388                         goto fr_authioctlloop;
 389                 break;
 390         case SIOCAUTHR:
 391                 if (!(mode & FWRITE)) {
 392                         error = EPERM;
 393                         break;
 394                 }
 395                 error = IRCOPYPTR(data, (caddr_t)&auth, sizeof(auth));
 396                 if (error)
 397                         return error;
 398                 WRITE_ENTER(&ipf_auth);
 399                 SPL_NET(s);
 400                 i = au->fra_index;
 401                 fra = fr_auth + i;
 402                 if ((i < 0) || (i > FR_NUMAUTH) ||
 403                     (fra->fra_info.fin_id != au->fra_info.fin_id)) {
 404                         SPL_X(s);
 405                         RWLOCK_EXIT(&ipf_auth);
 406                         return EINVAL;
 407                 }
 408                 m = fr_authpkts[i];
 409                 fra->fra_index = -2;
 410                 fra->fra_pass = au->fra_pass;
 411                 fr_authpkts[i] = NULL;
 412                 RWLOCK_EXIT(&ipf_auth);
 413 #ifdef  _KERNEL
 414                 if (m && au->fra_info.fin_out) {
 415 # if SOLARIS
 416                         error = (fr_qout(fra->fra_q, m) == 0) ? EINVAL : 0;
 417 # else /* SOLARIS */
 418                         struct route ro;
 419
 420                         bzero((char *)&ro, sizeof(ro));
 421 #  if ((_BSDI_VERSION >= 199802) && (_BSDI_VERSION < 200005)) || \
 422        defined(__DragonFly__) || defined(__OpenBSD__) || (defined(IRIX) && (IRIX >= 605)) || \
 423        (__FreeBSD_version >= 470102)
 424                         error = ip_output(m, NULL, &ro, IP_FORWARDING, NULL,
 425                                           NULL);
 426 #  else
 427                         error = ip_output(m, NULL, &ro, IP_FORWARDING, NULL);
 428 #  endif
 429                         if (ro.ro_rt) {
 430                                 RTFREE(ro.ro_rt);
 431                         }
 432 # endif /* SOLARIS */
 433                         if (error)
 434                                 fr_authstats.fas_sendfail++;
 435                         else
 436                                 fr_authstats.fas_sendok++;
 437                 } else if (m) {
 438 # if SOLARIS
 439                         error = (fr_qin(fra->fra_q, m) == 0) ? EINVAL : 0;
 440 # else /* SOLARIS */
 441 # if defined(__DragonFly__) || defined(__FreeBSD__)
 442                         error = netisr_queue(NETISR_IP, m);
 443 # else
 444                         ifq = &ipintrq;
 445                         if (IF_QFULL(ifq)) {
 446                                 IF_DROP(ifq);
 447                                 m_freem(m);
 448                                 error = ENOBUFS;
 449                         } else {
 450                                 IF_ENQUEUE(ifq, m);
 451 #  if IRIX < 605
 452                                 schednetisr(NETISR_IP);
 453 #  endif
 454                         }
 455 # endif
 456 # endif /* !SOLARIS */
 457                         if (error)
 458                                 fr_authstats.fas_quefail++;
 459                         else
 460                                 fr_authstats.fas_queok++;
 461                 } else
 462                         error = EINVAL;
 463 # if SOLARIS
 464                 if (error)
 465                         error = EINVAL;
 466 # else
 467                 /*
 468                  * If we experience an error which will result in the packet
 469                  * not being processed, make sure we advance to the next one.
 470                  */
 471                 if (error == ENOBUFS) {
 472                         fr_authused--;
 473                         fra->fra_index = -1;
 474                         fra->fra_pass = 0;
 475                         if (i == fr_authstart) {
 476                                 while (fra->fra_index == -1) {
 477                                         i++;
 478                                         if (i == FR_NUMAUTH)
 479                                                 i = 0;
 480                                         fr_authstart = i;
 481                                         if (i == fr_authend)
 482                                                 break;
 483                                 }
 484                                 if (fr_authstart == fr_authend) {
 485                                         fr_authnext = 0;
 486                                         fr_authstart = fr_authend = 0;
 487                                 }
 488                         }
 489                 }
 490 # endif
 491 #endif /* _KERNEL */
 492                 SPL_X(s);
 493                 break;
 494         default :
 495                 error = EINVAL;
 496                 break;
 497         }
 498         return error;
 499 }
 500
 501
 502 /*
 503  * Free all network buffer memory used to keep saved packets.
 504  */
 505 void fr_authunload()
 506 {
 507         int i;
 508         frauthent_t *fae, **faep;
 509         frentry_t *fr, **frp;
 510         mb_t *m;
 511
 512         WRITE_ENTER(&ipf_auth);
 513         for (i = 0; i < FR_NUMAUTH; i++) {
 514                 if ((m = fr_authpkts[i])) {
 515                         FREE_MB_T(m);
 516                         fr_authpkts[i] = NULL;
 517                         fr_auth[i].fra_index = -1;
 518                 }
 519         }
 520
 521
 522         for (faep = &fae_list; (fae = *faep); ) {
 523                 *faep = fae->fae_next;
 524                 KFREE(fae);
 525         }
 526         ipauth = NULL;
 527         RWLOCK_EXIT(&ipf_auth);
 528
 529         if (fr_authlist) {
 530                 /*
 531                  * We *MuST* reget ipf_auth because otherwise we won't get the
 532                  * locks in the right order and risk deadlock.
 533                  * We need ipf_mutex here to prevent a rule from using it
 534                  * inside fr_check().
 535                  */
 536                 WRITE_ENTER(&ipf_mutex);
 537                 WRITE_ENTER(&ipf_auth);
 538                 for (frp = &fr_authlist; (fr = *frp); ) {
 539                         if (fr->fr_ref == 1) {
 540                                 *frp = fr->fr_next;
 541                                 KFREE(fr);
 542                         } else
 543                                 frp = &fr->fr_next;
 544                 }
 545                 RWLOCK_EXIT(&ipf_auth);
 546                 RWLOCK_EXIT(&ipf_mutex);
 547         }
 548 }
 549
 550
 551 /*
 552  * Slowly expire held auth records.  Timeouts are set
 553  * in expectation of this being called twice per second.
 554  */
 555 void fr_authexpire()
 556 {
 557         int i;
 558         frauth_t *fra;
 559         frauthent_t *fae, **faep;
 560         frentry_t *fr, **frp;
 561         mb_t *m;
 562 #if !SOLARIS && defined(_KERNEL)
 563         int s;
 564 #endif
 565
 566         if (fr_auth_lock)
 567                 return;
 568
 569         SPL_NET(s);
 570         WRITE_ENTER(&ipf_auth);
 571         for (i = 0, fra = fr_auth; i < FR_NUMAUTH; i++, fra++) {
 572                 if ((!--fra->fra_age) && (m = fr_authpkts[i])) {
 573                         FREE_MB_T(m);
 574                         fr_authpkts[i] = NULL;
 575                         fr_auth[i].fra_index = -1;
 576                         fr_authstats.fas_expire++;
 577                         fr_authused--;
 578                 }
 579         }
 580
 581         for (faep = &fae_list; (fae = *faep); ) {
 582                 if (!--fae->fae_age) {
 583                         *faep = fae->fae_next;
 584                         KFREE(fae);
 585                         fr_authstats.fas_expire++;
 586                 } else
 587                         faep = &fae->fae_next;
 588         }
 589         if (fae_list != NULL)
 590                 ipauth = &fae_list->fae_fr;
 591         else
 592                 ipauth = NULL;
 593
 594         for (frp = &fr_authlist; (fr = *frp); ) {
 595                 if (fr->fr_ref == 1) {
 596                         *frp = fr->fr_next;
 597                         KFREE(fr);
 598                 } else
 599                         frp = &fr->fr_next;
 600         }
 601         RWLOCK_EXIT(&ipf_auth);
 602         SPL_X(s);
 603 }
 604
 605 int fr_preauthcmd(cmd, fr, frptr)
 606 #if defined(__DragonFly__) || defined(__NetBSD__) || defined(__OpenBSD__) || \
 607         (_BSDI_VERSION >= 199701) || (__FreeBSD_version >= 300000)
 608 u_long cmd;
 609 #else
 610 int cmd;
 611 #endif
 612 frentry_t *fr, **frptr;
 613 {
 614         frauthent_t *fae, **faep;
 615         int error = 0;
 616 #if defined(KERNEL) && !SOLARIS
 617         int s;
 618 #endif
 619
 620         if ((cmd != SIOCADAFR) && (cmd != SIOCRMAFR)) {
 621                 /* Should not happen */
 622                 printf("fr_preauthcmd called with bad cmd 0x%lx", (u_long)cmd);
 623                 return EIO;
 624         }
 625
 626         for (faep = &fae_list; (fae = *faep); )
 627                 if (&fae->fae_fr == fr)
 628                         break;
 629                 else
 630                         faep = &fae->fae_next;
 631         if (cmd == SIOCRMAFR) {
 632                 if (!fr || !frptr)
 633                         error = EINVAL;
 634                 else if (!fae)
 635                         error = ESRCH;
 636                 else {
 637                         WRITE_ENTER(&ipf_auth);
 638                         SPL_NET(s);
 639                         *faep = fae->fae_next;
 640                         *frptr = fr->fr_next;
 641                         SPL_X(s);
 642                         RWLOCK_EXIT(&ipf_auth);
 643                         KFREE(fae);
 644                 }
 645         } else if (fr && frptr) {
 646                 KMALLOC(fae, frauthent_t *);
 647                 if (fae != NULL) {
 648                         bcopy((char *)fr, (char *)&fae->fae_fr,
 649                               sizeof(*fr));
 650                         WRITE_ENTER(&ipf_auth);
 651                         SPL_NET(s);
 652                         fae->fae_age = fr_defaultauthage;
 653                         fae->fae_fr.fr_hits = 0;
 654                         fae->fae_fr.fr_next = *frptr;
 655                         *frptr = &fae->fae_fr;
 656                         fae->fae_next = *faep;
 657                         *faep = fae;
 658                         ipauth = &fae_list->fae_fr;
 659                         SPL_X(s);
 660                         RWLOCK_EXIT(&ipf_auth);
 661                 } else
 662                         error = ENOMEM;
 663         } else
 664                 error = EINVAL;
 665         return error;
 666 }