sys/contrib/ipfilter/netinet/ip_state.c

   1 /*      $FreeBSD$ */
   2
   3 /*
   4  * Copyright (C) 2012 by Darren Reed.
   5  *
   6  * See the IPFILTER.LICENCE file for details on licencing.
   7  *
   8  * Copyright 2008 Sun Microsystems.
   9  *
  10  * $Id$
  11  */
  12 #if defined(KERNEL) || defined(_KERNEL)
  13 # undef KERNEL
  14 # undef _KERNEL
  15 # define        KERNEL  1
  16 # define        _KERNEL 1
  17 #endif
  18 #include <sys/errno.h>
  19 #include <sys/types.h>
  20 #include <sys/param.h>
  21 #include <sys/file.h>
  22 #if defined(_KERNEL) && defined(__FreeBSD_version) && \
  23     (__FreeBSD_version >= 400000) && !defined(KLD_MODULE)
  24 #include "opt_inet6.h"
  25 #endif
  26 #if !defined(_KERNEL) && !defined(__KERNEL__)
  27 # include <stdio.h>
  28 # include <stdlib.h>
  29 # include <string.h>
  30 # define _KERNEL
  31 # ifdef __OpenBSD__
  32 struct file;
  33 # endif
  34 # include <sys/uio.h>
  35 # undef _KERNEL
  36 #endif
  37 #if defined(_KERNEL) && (__FreeBSD_version >= 220000)
  38 # include <sys/filio.h>
  39 # include <sys/fcntl.h>
  40 #else
  41 # include <sys/ioctl.h>
  42 #endif
  43 #include <sys/time.h>
  44 #if !defined(linux)
  45 # include <sys/protosw.h>
  46 #endif
  47 #include <sys/socket.h>
  48 #if defined(_KERNEL)
  49 # include <sys/systm.h>
  50 # if !defined(__SVR4) && !defined(__svr4__)
  51 #  include <sys/mbuf.h>
  52 # endif
  53 #endif
  54 #if defined(__SVR4) || defined(__svr4__)
  55 # include <sys/filio.h>
  56 # include <sys/byteorder.h>
  57 # ifdef _KERNEL
  58 #  include <sys/dditypes.h>
  59 # endif
  60 # include <sys/stream.h>
  61 # include <sys/kmem.h>
  62 #endif
  63
  64 #include <net/if.h>
  65 #ifdef sun
  66 # include <net/af.h>
  67 #endif
  68 #include <netinet/in.h>
  69 #include <netinet/in_systm.h>
  70 #include <netinet/ip.h>
  71 #include <netinet/tcp.h>
  72 #if !defined(__hpux) && !defined(linux)
  73 # include <netinet/tcp_fsm.h>
  74 #endif
  75 #include <netinet/udp.h>
  76 #include <netinet/ip_icmp.h>
  77 #if !defined(_KERNEL)
  78 # include "ipf.h"
  79 #endif
  80 #include "netinet/ip_compat.h"
  81 #include "netinet/ip_fil.h"
  82 #include "netinet/ip_nat.h"
  83 #include "netinet/ip_frag.h"
  84 #include "netinet/ip_state.h"
  85 #include "netinet/ip_proxy.h"
  86 #include "netinet/ip_lookup.h"
  87 #include "netinet/ip_dstlist.h"
  88 #include "netinet/ip_sync.h"
  89 #ifdef  USE_INET6
  90 #include <netinet/icmp6.h>
  91 #endif
  92 #if FREEBSD_GE_REV(300000)
  93 # include <sys/malloc.h>
  94 # if defined(_KERNEL) && !defined(IPFILTER_LKM)
  95 #  include <sys/libkern.h>
  96 #  include <sys/systm.h>
  97 # endif
  98 #endif
  99 /* END OF INCLUDES */
 100
 101
 102 #if !defined(lint)
 103 static const char sccsid[] = "@(#)ip_state.c    1.8 6/5/96 (C) 1993-2000 Darren Reed";
 104 static const char rcsid[] = "@(#)$Id$";
 105 #endif
 106
 107
 108 static ipftuneable_t ipf_state_tuneables[] = {
 109         { { (void *)offsetof(ipf_state_softc_t, ipf_state_max) },
 110                 "state_max",            1,      0x7fffffff,
 111                 stsizeof(ipf_state_softc_t, ipf_state_max),
 112                 0,                      NULL,   NULL },
 113         { { (void *)offsetof(ipf_state_softc_t, ipf_state_size) },
 114                 "state_size",           1,      0x7fffffff,
 115                 stsizeof(ipf_state_softc_t, ipf_state_size),
 116                 0,                      NULL,   ipf_state_rehash },
 117         { { (void *)offsetof(ipf_state_softc_t, ipf_state_lock) },
 118                 "state_lock",           0,      1,
 119                 stsizeof(ipf_state_softc_t, ipf_state_lock),
 120                 IPFT_RDONLY,            NULL,   NULL },
 121         { { (void *)offsetof(ipf_state_softc_t, ipf_state_maxbucket) },
 122                 "state_maxbucket",      1,      0x7fffffff,
 123                 stsizeof(ipf_state_softc_t, ipf_state_maxbucket),
 124                 0,                      NULL,   NULL },
 125         { { (void *)offsetof(ipf_state_softc_t, ipf_state_logging) },
 126                 "state_logging",0,      1,
 127                 stsizeof(ipf_state_softc_t, ipf_state_logging),
 128                 0,                      NULL,   NULL },
 129         { { (void *)offsetof(ipf_state_softc_t, ipf_state_wm_high) },
 130                 "state_wm_high",2,      100,
 131                 stsizeof(ipf_state_softc_t, ipf_state_wm_high),
 132                 0,                      NULL,   NULL },
 133         { { (void *)offsetof(ipf_state_softc_t, ipf_state_wm_low) },
 134                 "state_wm_low", 1,      99,
 135                 stsizeof(ipf_state_softc_t, ipf_state_wm_low),
 136                 0,                      NULL,   NULL },
 137         { { (void *)offsetof(ipf_state_softc_t, ipf_state_wm_freq) },
 138                 "state_wm_freq",2,      999999,
 139                 stsizeof(ipf_state_softc_t, ipf_state_wm_freq),
 140                 0,                      NULL,   NULL },
 141         { { NULL },
 142                 NULL,                   0,      0,
 143                 0,
 144                 0,      NULL, NULL }
 145 };
 146
 147 #define SINCL(x)        ATOMIC_INCL(softs->x)
 148 #define SBUMP(x)        (softs->x)++
 149 #define SBUMPD(x, y)    do { (softs->x.y)++; DT(y); } while (0)
 150 #define SBUMPDX(x, y, z)do { (softs->x.y)++; DT(z); } while (0)
 151
 152 #ifdef  USE_INET6
 153 static ipstate_t *ipf_checkicmp6matchingstate __P((fr_info_t *));
 154 #endif
 155 static int ipf_allowstateicmp __P((fr_info_t *, ipstate_t *, i6addr_t *));
 156 static ipstate_t *ipf_matchsrcdst __P((fr_info_t *, ipstate_t *, i6addr_t *,
 157                                       i6addr_t *, tcphdr_t *, u_32_t));
 158 static ipstate_t *ipf_checkicmpmatchingstate __P((fr_info_t *));
 159 static int ipf_state_flush_entry __P((ipf_main_softc_t *, void *));
 160 static ips_stat_t *ipf_state_stats __P((ipf_main_softc_t *));
 161 static int ipf_state_del __P((ipf_main_softc_t *, ipstate_t *, int));
 162 static int ipf_state_remove __P((ipf_main_softc_t *, caddr_t));
 163 static int ipf_state_match __P((ipstate_t *is1, ipstate_t *is2));
 164 static int ipf_state_matchaddresses __P((ipstate_t *is1, ipstate_t *is2));
 165 static int ipf_state_matchipv4addrs __P((ipstate_t *is1, ipstate_t *is2));
 166 static int ipf_state_matchipv6addrs __P((ipstate_t *is1, ipstate_t *is2));
 167 static int ipf_state_matchisps __P((ipstate_t *is1, ipstate_t *is2));
 168 static int ipf_state_matchports __P((udpinfo_t *is1, udpinfo_t *is2));
 169 static int ipf_state_matcharray __P((ipstate_t *, int *, u_long));
 170 static void ipf_ipsmove __P((ipf_state_softc_t *, ipstate_t *, u_int));
 171 static int ipf_state_tcp __P((ipf_main_softc_t *, ipf_state_softc_t *,
 172                               fr_info_t *, tcphdr_t *, ipstate_t *));
 173 static int ipf_tcpoptions __P((ipf_state_softc_t *, fr_info_t *,
 174                                tcphdr_t *, tcpdata_t *));
 175 static ipstate_t *ipf_state_clone __P((fr_info_t *, tcphdr_t *, ipstate_t *));
 176 static void ipf_fixinisn __P((fr_info_t *, ipstate_t *));
 177 static void ipf_fixoutisn __P((fr_info_t *, ipstate_t *));
 178 static void ipf_checknewisn __P((fr_info_t *, ipstate_t *));
 179 static int ipf_state_iter __P((ipf_main_softc_t *, ipftoken_t *,
 180                                ipfgeniter_t *, ipfobj_t *));
 181 static int ipf_state_gettable __P((ipf_main_softc_t *, ipf_state_softc_t *,
 182                                    char *));
 183 static  int ipf_state_tcpinwindow __P((struct fr_info *, struct tcpdata *,
 184                                        struct tcpdata *, tcphdr_t *, int));
 185
 186 static int ipf_state_getent __P((ipf_main_softc_t *, ipf_state_softc_t *,
 187                                  caddr_t));
 188 static int ipf_state_putent __P((ipf_main_softc_t *, ipf_state_softc_t *,
 189                                  caddr_t));
 190
 191 #define ONE_DAY         IPF_TTLVAL(1 * 86400)   /* 1 day */
 192 #define FIVE_DAYS       (5 * ONE_DAY)
 193 #define DOUBLE_HASH(x)  (((x) + softs->ipf_state_seed[(x) % \
 194                          softs->ipf_state_size]) % softs->ipf_state_size)
 195
 196
 197 /* ------------------------------------------------------------------------ */
 198 /* Function:    ipf_state_main_load                                         */
 199 /* Returns:     int - 0 == success, -1 == failure                           */
 200 /* Parameters:  Nil                                                         */
 201 /*                                                                          */
 202 /* A null-op function that exists as a placeholder so that the flow in      */
 203 /* other functions is obvious.                                              */
 204 /* ------------------------------------------------------------------------ */
 205 int
 206 ipf_state_main_load()
 207 {
 208         return 0;
 209 }
 210
 211
 212 /* ------------------------------------------------------------------------ */
 213 /* Function:    ipf_state_main_unload                                       */
 214 /* Returns:     int - 0 == success, -1 == failure                           */
 215 /* Parameters:  Nil                                                         */
 216 /*                                                                          */
 217 /* A null-op function that exists as a placeholder so that the flow in      */
 218 /* other functions is obvious.                                              */
 219 /* ------------------------------------------------------------------------ */
 220 int
 221 ipf_state_main_unload()
 222 {
 223         return 0;
 224 }
 225
 226
 227 /* ------------------------------------------------------------------------ */
 228 /* Function:    ipf_state_soft_create                                       */
 229 /* Returns:     void *   - NULL = failure, else pointer to soft context     */
 230 /* Parameters:  softc(I) - pointer to soft context main structure           */
 231 /*                                                                          */
 232 /* Create a new state soft context structure and populate it with the list  */
 233 /* of tunables and other default settings.                                  */
 234 /* ------------------------------------------------------------------------ */
 235 void *
 236 ipf_state_soft_create(softc)
 237         ipf_main_softc_t *softc;
 238 {
 239         ipf_state_softc_t *softs;
 240
 241         KMALLOC(softs, ipf_state_softc_t *);
 242         if (softs == NULL)
 243                 return NULL;
 244
 245         bzero((char *)softs, sizeof(*softs));
 246
 247         softs->ipf_state_tune = ipf_tune_array_copy(softs,
 248                                                     sizeof(ipf_state_tuneables),
 249                                                     ipf_state_tuneables);
 250         if (softs->ipf_state_tune == NULL) {
 251                 ipf_state_soft_destroy(softc, softs);
 252                 return NULL;
 253         }
 254         if (ipf_tune_array_link(softc, softs->ipf_state_tune) == -1) {
 255                 ipf_state_soft_destroy(softc, softs);
 256                 return NULL;
 257         }
 258
 259 #ifdef  IPFILTER_LOG
 260         softs->ipf_state_logging = 1;
 261 #else
 262         softs->ipf_state_logging = 0;
 263 #endif
 264         softs->ipf_state_size = IPSTATE_SIZE,
 265         softs->ipf_state_maxbucket = 0;
 266         softs->ipf_state_wm_freq = IPF_TTLVAL(10);
 267         softs->ipf_state_max = IPSTATE_MAX;
 268         softs->ipf_state_wm_last = 0;
 269         softs->ipf_state_wm_high = 99;
 270         softs->ipf_state_wm_low = 90;
 271         softs->ipf_state_inited = 0;
 272         softs->ipf_state_lock = 0;
 273         softs->ipf_state_doflush = 0;
 274
 275         return softs;
 276 }
 277
 278
 279 /* ------------------------------------------------------------------------ */
 280 /* Function:    ipf_state_soft_destroy                                      */
 281 /* Returns:     Nil                                                         */
 282 /* Parameters:  softc(I) - pointer to soft context main structure           */
 283 /*              arg(I)   - pointer to local context to use                  */
 284 /*                                                                          */
 285 /* Undo only what we did in soft create: unlink and free the tunables and   */
 286 /* free the soft context structure itself.                                  */
 287 /* ------------------------------------------------------------------------ */
 288 void
 289 ipf_state_soft_destroy(softc, arg)
 290         ipf_main_softc_t *softc;
 291         void *arg;
 292 {
 293         ipf_state_softc_t *softs = arg;
 294
 295         if (softs->ipf_state_tune != NULL) {
 296                 ipf_tune_array_unlink(softc, softs->ipf_state_tune);
 297                 KFREES(softs->ipf_state_tune, sizeof(ipf_state_tuneables));
 298                 softs->ipf_state_tune = NULL;
 299         }
 300
 301         KFREE(softs);
 302 }
 303
 304 static void *
 305 ipf_state_seed_alloc(u_int state_size, u_int state_max)
 306 {
 307         u_int i;
 308         u_long *state_seed;
 309         KMALLOCS(state_seed, u_long *, state_size * sizeof(*state_seed));
 310         if (state_seed == NULL)
 311                 return NULL;
 312
 313         for (i = 0; i < state_size; i++) {
 314                 /*
 315                  * XXX - ipf_state_seed[X] should be a random number of sorts.
 316                  */
 317 #if  FREEBSD_GE_REV(400000)
 318                 state_seed[i] = arc4random();
 319 #else
 320                 state_seed[i] = ((u_long)state_seed + i) * state_size;
 321                 state_seed[i] ^= 0xa5a55a5a;
 322                 state_seed[i] *= (u_long)state_seed;
 323                 state_seed[i] ^= 0x5a5aa5a5;
 324                 state_seed[i] *= state_max;
 325 #endif
 326         }
 327         return state_seed;
 328 }
 329
 330
 331 /* ------------------------------------------------------------------------ */
 332 /* Function:    ipf_state_soft_init                                         */
 333 /* Returns:     int      - 0 == success, -1 == failure                      */
 334 /* Parameters:  softc(I) - pointer to soft context main structure           */
 335 /*              arg(I)   - pointer to local context to use                  */
 336 /*                                                                          */
 337 /* Initialise the state soft context structure so it is ready for use.      */
 338 /* This involves:                                                           */
 339 /* - allocating a hash table and zero'ing it out                            */
 340 /* - building a secondary table of seeds for double hashing to make it more */
 341 /*   difficult to attempt to attack the hash table itself (for DoS)         */
 342 /* - initialise all of the timeout queues, including a table for TCP, some  */
 343 /*   pairs of query/response for UDP and other IP protocols (typically the  */
 344 /*   reply queue has a shorter timeout than the query)                      */
 345 /* ------------------------------------------------------------------------ */
 346 int
 347 ipf_state_soft_init(softc, arg)
 348         ipf_main_softc_t *softc;
 349         void *arg;
 350 {
 351         ipf_state_softc_t *softs = arg;
 352         int i;
 353
 354         KMALLOCS(softs->ipf_state_table,
 355                  ipstate_t **, softs->ipf_state_size * sizeof(ipstate_t *));
 356         if (softs->ipf_state_table == NULL)
 357                 return -1;
 358
 359         bzero((char *)softs->ipf_state_table,
 360               softs->ipf_state_size * sizeof(ipstate_t *));
 361
 362         softs->ipf_state_seed = ipf_state_seed_alloc(softs->ipf_state_size,
 363             softs->ipf_state_max);
 364         if (softs->ipf_state_seed == NULL)
 365                 return -2;
 366
 367         KMALLOCS(softs->ipf_state_stats.iss_bucketlen, u_int *,
 368                  softs->ipf_state_size * sizeof(u_int));
 369         if (softs->ipf_state_stats.iss_bucketlen == NULL)
 370                 return -3;
 371
 372         bzero((char *)softs->ipf_state_stats.iss_bucketlen,
 373               softs->ipf_state_size * sizeof(u_int));
 374
 375         if (softs->ipf_state_maxbucket == 0) {
 376                 for (i = softs->ipf_state_size; i > 0; i >>= 1)
 377                         softs->ipf_state_maxbucket++;
 378                 softs->ipf_state_maxbucket *= 2;
 379         }
 380
 381         ipf_sttab_init(softc, softs->ipf_state_tcptq);
 382         softs->ipf_state_stats.iss_tcptab = softs->ipf_state_tcptq;
 383         softs->ipf_state_tcptq[IPF_TCP_NSTATES - 1].ifq_next =
 384                                                 &softs->ipf_state_udptq;
 385
 386         IPFTQ_INIT(&softs->ipf_state_udptq, softc->ipf_udptimeout,
 387                    "ipftq udp tab");
 388         softs->ipf_state_udptq.ifq_next = &softs->ipf_state_udpacktq;
 389
 390         IPFTQ_INIT(&softs->ipf_state_udpacktq, softc->ipf_udpacktimeout,
 391                    "ipftq udpack tab");
 392         softs->ipf_state_udpacktq.ifq_next = &softs->ipf_state_icmptq;
 393
 394         IPFTQ_INIT(&softs->ipf_state_icmptq, softc->ipf_icmptimeout,
 395                    "ipftq icmp tab");
 396         softs->ipf_state_icmptq.ifq_next = &softs->ipf_state_icmpacktq;
 397
 398         IPFTQ_INIT(&softs->ipf_state_icmpacktq, softc->ipf_icmpacktimeout,
 399                   "ipftq icmpack tab");
 400         softs->ipf_state_icmpacktq.ifq_next = &softs->ipf_state_iptq;
 401
 402         IPFTQ_INIT(&softs->ipf_state_iptq, softc->ipf_iptimeout,
 403                    "ipftq iptimeout tab");
 404         softs->ipf_state_iptq.ifq_next = &softs->ipf_state_pending;
 405
 406         IPFTQ_INIT(&softs->ipf_state_pending, IPF_HZ_DIVIDE, "ipftq pending");
 407         softs->ipf_state_pending.ifq_next = &softs->ipf_state_deletetq;
 408
 409         IPFTQ_INIT(&softs->ipf_state_deletetq, 1, "ipftq delete");
 410         softs->ipf_state_deletetq.ifq_next = NULL;
 411
 412         MUTEX_INIT(&softs->ipf_stinsert, "ipf state insert mutex");
 413
 414
 415         softs->ipf_state_wm_last = softc->ipf_ticks;
 416         softs->ipf_state_inited = 1;
 417
 418         return 0;
 419 }
 420
 421
 422 /* ------------------------------------------------------------------------ */
 423 /* Function:    ipf_state_soft_fini                                         */
 424 /* Returns:     int      - 0 = success, -1 = failure                        */
 425 /* Parameters:  softc(I) - pointer to soft context main structure           */
 426 /*              arg(I)   - pointer to local context to use                  */
 427 /*                                                                          */
 428 /* Release and destroy any resources acquired or initialised so that        */
 429 /* IPFilter can be unloaded or re-initialised.                              */
 430 /* ------------------------------------------------------------------------ */
 431 int
 432 ipf_state_soft_fini(softc, arg)
 433         ipf_main_softc_t *softc;
 434         void *arg;
 435 {
 436         ipf_state_softc_t *softs = arg;
 437         ipftq_t *ifq, *ifqnext;
 438         ipstate_t *is;
 439
 440         while ((is = softs->ipf_state_list) != NULL)
 441                 ipf_state_del(softc, is, ISL_UNLOAD);
 442
 443         /*
 444          * Proxy timeout queues are not cleaned here because although they
 445          * exist on the state list, appr_unload is called after
 446          * ipf_state_unload and the proxies actually are responsible for them
 447          * being created. Should the proxy timeouts have their own list?
 448          * There's no real justification as this is the only complication.
 449          */
 450         for (ifq = softs->ipf_state_usertq; ifq != NULL; ifq = ifqnext) {
 451                 ifqnext = ifq->ifq_next;
 452
 453                 if (ipf_deletetimeoutqueue(ifq) == 0)
 454                         ipf_freetimeoutqueue(softc, ifq);
 455         }
 456
 457         softs->ipf_state_stats.iss_inuse = 0;
 458         softs->ipf_state_stats.iss_active = 0;
 459
 460         if (softs->ipf_state_inited == 1) {
 461                 softs->ipf_state_inited = 0;
 462                 ipf_sttab_destroy(softs->ipf_state_tcptq);
 463                 MUTEX_DESTROY(&softs->ipf_state_udptq.ifq_lock);
 464                 MUTEX_DESTROY(&softs->ipf_state_icmptq.ifq_lock);
 465                 MUTEX_DESTROY(&softs->ipf_state_udpacktq.ifq_lock);
 466                 MUTEX_DESTROY(&softs->ipf_state_icmpacktq.ifq_lock);
 467                 MUTEX_DESTROY(&softs->ipf_state_iptq.ifq_lock);
 468                 MUTEX_DESTROY(&softs->ipf_state_deletetq.ifq_lock);
 469                 MUTEX_DESTROY(&softs->ipf_state_pending.ifq_lock);
 470                 MUTEX_DESTROY(&softs->ipf_stinsert);
 471         }
 472
 473         if (softs->ipf_state_table != NULL) {
 474                 KFREES(softs->ipf_state_table,
 475                        softs->ipf_state_size * sizeof(*softs->ipf_state_table));
 476                 softs->ipf_state_table = NULL;
 477         }
 478
 479         if (softs->ipf_state_seed != NULL) {
 480                 KFREES(softs->ipf_state_seed,
 481                        softs->ipf_state_size * sizeof(*softs->ipf_state_seed));
 482                 softs->ipf_state_seed = NULL;
 483         }
 484
 485         if (softs->ipf_state_stats.iss_bucketlen != NULL) {
 486                 KFREES(softs->ipf_state_stats.iss_bucketlen,
 487                        softs->ipf_state_size * sizeof(u_int));
 488                 softs->ipf_state_stats.iss_bucketlen = NULL;
 489         }
 490
 491         return 0;
 492 }
 493
 494
 495 /* ------------------------------------------------------------------------ */
 496 /* Function:    ipf_state_setlock                                           */
 497 /* Returns:     Nil                                                         */
 498 /* Parameters:  arg(I) - pointer to local context to use                    */
 499 /*              tmp(I) - new value for lock                                 */
 500 /*                                                                          */
 501 /* Stub function that allows for external manipulation of ipf_state_lock    */
 502 /* ------------------------------------------------------------------------ */
 503 void
 504 ipf_state_setlock(arg, tmp)
 505         void *arg;
 506         int tmp;
 507 {
 508         ipf_state_softc_t *softs = arg;
 509
 510         softs->ipf_state_lock = tmp;
 511 }
 512
 513
 514 /* ------------------------------------------------------------------------ */
 515 /* Function:    ipf_state_stats                                             */
 516 /* Returns:     ips_state_t* - pointer to state stats structure             */
 517 /* Parameters:  softc(I) - pointer to soft context main structure           */
 518 /*                                                                          */
 519 /* Put all the current numbers and pointers into a single struct and return */
 520 /* a pointer to it.                                                         */
 521 /* ------------------------------------------------------------------------ */
 522 static ips_stat_t *
 523 ipf_state_stats(softc)
 524         ipf_main_softc_t *softc;
 525 {
 526         ipf_state_softc_t *softs = softc->ipf_state_soft;
 527         ips_stat_t *issp = &softs->ipf_state_stats;
 528
 529         issp->iss_state_size = softs->ipf_state_size;
 530         issp->iss_state_max = softs->ipf_state_max;
 531         issp->iss_table = softs->ipf_state_table;
 532         issp->iss_list = softs->ipf_state_list;
 533         issp->iss_ticks = softc->ipf_ticks;
 534
 535 #ifdef IPFILTER_LOGGING
 536         issp->iss_log_ok = ipf_log_logok(softc, IPF_LOGSTATE);
 537         issp->iss_log_fail = ipf_log_failures(softc, IPF_LOGSTATE);
 538 #else
 539         issp->iss_log_ok = 0;
 540         issp->iss_log_fail = 0;
 541 #endif
 542         return issp;
 543 }
 544
 545 /* ------------------------------------------------------------------------ */
 546 /* Function:    ipf_state_remove                                            */
 547 /* Returns:     int - 0 == success, != 0 == failure                         */
 548 /* Parameters:  softc(I) - pointer to soft context main structure           */
 549 /*              data(I)  - pointer to state structure to delete from table  */
 550 /*                                                                          */
 551 /* Search for a state structure that matches the one passed, according to   */
 552 /* the IP addresses and other protocol specific information.                */
 553 /* ------------------------------------------------------------------------ */
 554 static int
 555 ipf_state_remove(softc, data)
 556         ipf_main_softc_t *softc;
 557         caddr_t data;
 558 {
 559         ipf_state_softc_t *softs = softc->ipf_state_soft;
 560         ipstate_t *sp, st;
 561         int error;
 562
 563         sp = &st;
 564         error = ipf_inobj(softc, data, NULL, &st, IPFOBJ_IPSTATE);
 565         if (error)
 566                 return EFAULT;
 567
 568         WRITE_ENTER(&softc->ipf_state);
 569         for (sp = softs->ipf_state_list; sp; sp = sp->is_next)
 570                 if ((sp->is_p == st.is_p) && (sp->is_v == st.is_v) &&
 571                     !bcmp((caddr_t)&sp->is_src, (caddr_t)&st.is_src,
 572                           sizeof(st.is_src)) &&
 573                     !bcmp((caddr_t)&sp->is_dst, (caddr_t)&st.is_dst,
 574                           sizeof(st.is_dst)) &&
 575                     !bcmp((caddr_t)&sp->is_ps, (caddr_t)&st.is_ps,
 576                           sizeof(st.is_ps))) {
 577                         ipf_state_del(softc, sp, ISL_REMOVE);
 578                         RWLOCK_EXIT(&softc->ipf_state);
 579                         return 0;
 580                 }
 581         RWLOCK_EXIT(&softc->ipf_state);
 582
 583         IPFERROR(100001);
 584         return ESRCH;
 585 }
 586
 587
 588 /* ------------------------------------------------------------------------ */
 589 /* Function:    ipf_state_ioctl                                             */
 590 /* Returns:     int - 0 == success, != 0 == failure                         */
 591 /* Parameters:  softc(I) - pointer to soft context main structure           */
 592 /*              data(I)  - pointer to ioctl data                            */
 593 /*              cmd(I)   - ioctl command integer                            */
 594 /*              mode(I)  - file mode bits used with open                    */
 595 /*              uid(I)   - uid of process making the ioctl call             */
 596 /*              ctx(I)   - pointer specific to context of the call          */
 597 /*                                                                          */
 598 /* Processes an ioctl call made to operate on the IP Filter state device.   */
 599 /* ------------------------------------------------------------------------ */
 600 int
 601 ipf_state_ioctl(softc, data, cmd, mode, uid, ctx)
 602         ipf_main_softc_t *softc;
 603         caddr_t data;
 604         ioctlcmd_t cmd;
 605         int mode, uid;
 606         void *ctx;
 607 {
 608         ipf_state_softc_t *softs = softc->ipf_state_soft;
 609         int arg, ret, error = 0;
 610         SPL_INT(s);
 611
 612         switch (cmd)
 613         {
 614         /*
 615          * Delete an entry from the state table.
 616          */
 617         case SIOCDELST :
 618                 error = ipf_state_remove(softc, data);
 619                 break;
 620
 621         /*
 622          * Flush the state table
 623          */
 624         case SIOCIPFFL :
 625                 error = BCOPYIN(data, &arg, sizeof(arg));
 626                 if (error != 0) {
 627                         IPFERROR(100002);
 628                         error = EFAULT;
 629
 630                 } else {
 631                         WRITE_ENTER(&softc->ipf_state);
 632                         ret = ipf_state_flush(softc, arg, 4);
 633                         RWLOCK_EXIT(&softc->ipf_state);
 634
 635                         error = BCOPYOUT(&ret, data, sizeof(ret));
 636                         if (error != 0) {
 637                                 IPFERROR(100003);
 638                                 error = EFAULT;
 639                         }
 640                 }
 641                 break;
 642
 643 #ifdef  USE_INET6
 644         case SIOCIPFL6 :
 645                 error = BCOPYIN(data, &arg, sizeof(arg));
 646                 if (error != 0) {
 647                         IPFERROR(100004);
 648                         error = EFAULT;
 649
 650                 } else {
 651                         WRITE_ENTER(&softc->ipf_state);
 652                         ret = ipf_state_flush(softc, arg, 6);
 653                         RWLOCK_EXIT(&softc->ipf_state);
 654
 655                         error = BCOPYOUT(&ret, data, sizeof(ret));
 656                         if (error != 0) {
 657                                 IPFERROR(100005);
 658                                 error = EFAULT;
 659                         }
 660                 }
 661                 break;
 662 #endif
 663
 664         case SIOCMATCHFLUSH :
 665                 WRITE_ENTER(&softc->ipf_state);
 666                 error = ipf_state_matchflush(softc, data);
 667                 RWLOCK_EXIT(&softc->ipf_state);
 668                 break;
 669
 670 #ifdef  IPFILTER_LOG
 671         /*
 672          * Flush the state log.
 673          */
 674         case SIOCIPFFB :
 675                 if (!(mode & FWRITE)) {
 676                         IPFERROR(100008);
 677                         error = EPERM;
 678                 } else {
 679                         int tmp;
 680
 681                         tmp = ipf_log_clear(softc, IPL_LOGSTATE);
 682                         error = BCOPYOUT(&tmp, data, sizeof(tmp));
 683                         if (error != 0) {
 684                                 IPFERROR(100009);
 685                                 error = EFAULT;
 686                         }
 687                 }
 688                 break;
 689
 690         /*
 691          * Turn logging of state information on/off.
 692          */
 693         case SIOCSETLG :
 694                 if (!(mode & FWRITE)) {
 695                         IPFERROR(100010);
 696                         error = EPERM;
 697                 } else {
 698                         error = BCOPYIN(data, &softs->ipf_state_logging,
 699                                         sizeof(softs->ipf_state_logging));
 700                         if (error != 0) {
 701                                 IPFERROR(100011);
 702                                 error = EFAULT;
 703                         }
 704                 }
 705                 break;
 706
 707         /*
 708          * Return the current state of logging.
 709          */
 710         case SIOCGETLG :
 711                 error = BCOPYOUT(&softs->ipf_state_logging, data,
 712                                  sizeof(softs->ipf_state_logging));
 713                 if (error != 0) {
 714                         IPFERROR(100012);
 715                         error = EFAULT;
 716                 }
 717                 break;
 718
 719         /*
 720          * Return the number of bytes currently waiting to be read.
 721          */
 722         case FIONREAD :
 723                 arg = ipf_log_bytesused(softc, IPL_LOGSTATE);
 724                 error = BCOPYOUT(&arg, data, sizeof(arg));
 725                 if (error != 0) {
 726                         IPFERROR(100013);
 727                         error = EFAULT;
 728                 }
 729                 break;
 730 #endif
 731
 732         /*
 733          * Get the current state statistics.
 734          */
 735         case SIOCGETFS :
 736                 error = ipf_outobj(softc, data, ipf_state_stats(softc),
 737                                    IPFOBJ_STATESTAT);
 738                 break;
 739
 740         /*
 741          * Lock/Unlock the state table.  (Locking prevents any changes, which
 742          * means no packets match).
 743          */
 744         case SIOCSTLCK :
 745                 if (!(mode & FWRITE)) {
 746                         IPFERROR(100014);
 747                         error = EPERM;
 748                 } else {
 749                         error = ipf_lock(data, &softs->ipf_state_lock);
 750                 }
 751                 break;
 752
 753         /*
 754          * Add an entry to the current state table.
 755          */
 756         case SIOCSTPUT :
 757                 if (!softs->ipf_state_lock || !(mode &FWRITE)) {
 758                         IPFERROR(100015);
 759                         error = EACCES;
 760                         break;
 761                 }
 762                 error = ipf_state_putent(softc, softs, data);
 763                 break;
 764
 765         /*
 766          * Get a state table entry.
 767          */
 768         case SIOCSTGET :
 769                 if (!softs->ipf_state_lock) {
 770                         IPFERROR(100016);
 771                         error = EACCES;
 772                         break;
 773                 }
 774                 error = ipf_state_getent(softc, softs, data);
 775                 break;
 776
 777         /*
 778          * Return a copy of the hash table bucket lengths
 779          */
 780         case SIOCSTAT1 :
 781                 error = BCOPYOUT(softs->ipf_state_stats.iss_bucketlen, data,
 782                                  softs->ipf_state_size * sizeof(u_int));
 783                 if (error != 0) {
 784                         IPFERROR(100017);
 785                         error = EFAULT;
 786                 }
 787                 break;
 788
 789         case SIOCGENITER :
 790             {
 791                 ipftoken_t *token;
 792                 ipfgeniter_t iter;
 793                 ipfobj_t obj;
 794
 795                 error = ipf_inobj(softc, data, &obj, &iter, IPFOBJ_GENITER);
 796                 if (error != 0)
 797                         break;
 798
 799                 SPL_SCHED(s);
 800                 token = ipf_token_find(softc, IPFGENITER_STATE, uid, ctx);
 801                 if (token != NULL) {
 802                         error = ipf_state_iter(softc, token, &iter, &obj);
 803                         WRITE_ENTER(&softc->ipf_tokens);
 804                         ipf_token_deref(softc, token);
 805                         RWLOCK_EXIT(&softc->ipf_tokens);
 806                 } else {
 807                         IPFERROR(100018);
 808                         error = ESRCH;
 809                 }
 810                 SPL_X(s);
 811                 break;
 812             }
 813
 814         case SIOCGTABL :
 815                 error = ipf_state_gettable(softc, softs, data);
 816                 break;
 817
 818         case SIOCIPFDELTOK :
 819                 error = BCOPYIN(data, &arg, sizeof(arg));
 820                 if (error != 0) {
 821                         IPFERROR(100019);
 822                         error = EFAULT;
 823                 } else {
 824                         SPL_SCHED(s);
 825                         error = ipf_token_del(softc, arg, uid, ctx);
 826                         SPL_X(s);
 827                 }
 828                 break;
 829
 830         case SIOCGTQTAB :
 831                 error = ipf_outobj(softc, data, softs->ipf_state_tcptq,
 832                                    IPFOBJ_STATETQTAB);
 833                 break;
 834
 835         default :
 836                 IPFERROR(100020);
 837                 error = EINVAL;
 838                 break;
 839         }
 840         return error;
 841 }
 842
 843
 844 /* ------------------------------------------------------------------------ */
 845 /* Function:    ipf_state_getent                                            */
 846 /* Returns:     int - 0 == success, != 0 == failure                         */
 847 /* Parameters:  softc(I) - pointer to soft context main structure           */
 848 /*              softs(I) - pointer to state context structure               */
 849 /*              data(I)  - pointer to state structure to retrieve from table*/
 850 /*                                                                          */
 851 /* Copy out state information from the kernel to a user space process.  If  */
 852 /* there is a filter rule associated with the state entry, copy that out    */
 853 /* as well.  The entry to copy out is taken from the value of "ips_next" in */
 854 /* the struct passed in and if not null and not found in the list of current*/
 855 /* state entries, the retrieval fails.                                      */
 856 /* ------------------------------------------------------------------------ */
 857 static int
 858 ipf_state_getent(softc, softs, data)
 859         ipf_main_softc_t *softc;
 860         ipf_state_softc_t *softs;
 861         caddr_t data;
 862 {
 863         ipstate_t *is, *isn;
 864         ipstate_save_t ips;
 865         int error;
 866
 867         error = ipf_inobj(softc, data, NULL, &ips, IPFOBJ_STATESAVE);
 868         if (error)
 869                 return EFAULT;
 870
 871         READ_ENTER(&softc->ipf_state);
 872         isn = ips.ips_next;
 873         if (isn == NULL) {
 874                 isn = softs->ipf_state_list;
 875                 if (isn == NULL) {
 876                         if (ips.ips_next == NULL) {
 877                                 RWLOCK_EXIT(&softc->ipf_state);
 878                                 IPFERROR(100021);
 879                                 return ENOENT;
 880                         }
 881                         return 0;
 882                 }
 883         } else {
 884                 /*
 885                  * Make sure the pointer we're copying from exists in the
 886                  * current list of entries.  Security precaution to prevent
 887                  * copying of random kernel data.
 888                  */
 889                 for (is = softs->ipf_state_list; is; is = is->is_next)
 890                         if (is == isn)
 891                                 break;
 892                 if (!is) {
 893                         RWLOCK_EXIT(&softc->ipf_state);
 894                         IPFERROR(100022);
 895                         return ESRCH;
 896                 }
 897         }
 898         ips.ips_next = isn->is_next;
 899         bcopy((char *)isn, (char *)&ips.ips_is, sizeof(ips.ips_is));
 900         ips.ips_rule = isn->is_rule;
 901         if (isn->is_rule != NULL)
 902                 bcopy((char *)isn->is_rule, (char *)&ips.ips_fr,
 903                       sizeof(ips.ips_fr));
 904         RWLOCK_EXIT(&softc->ipf_state);
 905         error = ipf_outobj(softc, data, &ips, IPFOBJ_STATESAVE);
 906         return error;
 907 }
 908
 909
 910 /* ------------------------------------------------------------------------ */
 911 /* Function:    ipf_state_putent                                            */
 912 /* Returns:     int - 0 == success, != 0 == failure                         */
 913 /* Parameters:  softc(I) - pointer to soft context main structure           */
 914 /*              softs(I) - pointer to state context structure               */
 915 /*              data(I)  - pointer to state information struct              */
 916 /*                                                                          */
 917 /* This function implements the SIOCSTPUT ioctl: insert a state entry into  */
 918 /* the state table.  If the state info. includes a pointer to a filter rule */
 919 /* then also add in an orphaned rule (will not show up in any "ipfstat -io" */
 920 /* output.                                                                  */
 921 /* ------------------------------------------------------------------------ */
 922 int
 923 ipf_state_putent(softc, softs, data)
 924         ipf_main_softc_t *softc;
 925         ipf_state_softc_t *softs;
 926         caddr_t data;
 927 {
 928         ipstate_t *is, *isn;
 929         ipstate_save_t ips;
 930         int error, out, i;
 931         frentry_t *fr;
 932         char *name;
 933
 934         error = ipf_inobj(softc, data, NULL, &ips, IPFOBJ_STATESAVE);
 935         if (error != 0)
 936                 return error;
 937
 938         KMALLOC(isn, ipstate_t *);
 939         if (isn == NULL) {
 940                 IPFERROR(100023);
 941                 return ENOMEM;
 942         }
 943
 944         bcopy((char *)&ips.ips_is, (char *)isn, sizeof(*isn));
 945         bzero((char *)isn, offsetof(struct ipstate, is_pkts));
 946         isn->is_sti.tqe_pnext = NULL;
 947         isn->is_sti.tqe_next = NULL;
 948         isn->is_sti.tqe_ifq = NULL;
 949         isn->is_sti.tqe_parent = isn;
 950         isn->is_ifp[0] = NULL;
 951         isn->is_ifp[1] = NULL;
 952         isn->is_ifp[2] = NULL;
 953         isn->is_ifp[3] = NULL;
 954         isn->is_sync = NULL;
 955         fr = ips.ips_rule;
 956
 957         if (fr == NULL) {
 958                 int inserr;
 959
 960                 READ_ENTER(&softc->ipf_state);
 961                 inserr = ipf_state_insert(softc, isn, 0);
 962                 MUTEX_EXIT(&isn->is_lock);
 963                 RWLOCK_EXIT(&softc->ipf_state);
 964
 965                 return inserr;
 966         }
 967
 968         if (isn->is_flags & SI_NEWFR) {
 969                 KMALLOC(fr, frentry_t *);
 970                 if (fr == NULL) {
 971                         KFREE(isn);
 972                         IPFERROR(100024);
 973                         return ENOMEM;
 974                 }
 975                 bcopy((char *)&ips.ips_fr, (char *)fr, sizeof(*fr));
 976                 out = fr->fr_flags & FR_OUTQUE ? 1 : 0;
 977                 isn->is_rule = fr;
 978                 ips.ips_is.is_rule = fr;
 979                 MUTEX_NUKE(&fr->fr_lock);
 980                 MUTEX_INIT(&fr->fr_lock, "state filter rule lock");
 981
 982                 /*
 983                  * Look up all the interface names in the rule.
 984                  */
 985                 for (i = 0; i < 4; i++) {
 986                         if (fr->fr_ifnames[i] == -1) {
 987                                 fr->fr_ifas[i] = NULL;
 988                                 continue;
 989                         }
 990                         name = fr->fr_names + fr->fr_ifnames[i];
 991                         fr->fr_ifas[i] = ipf_resolvenic(softc, name,
 992                                                         fr->fr_family);
 993                 }
 994
 995                 for (i = 0; i < 4; i++) {
 996                         name = isn->is_ifname[i];
 997                         isn->is_ifp[i] = ipf_resolvenic(softc, name,
 998                                                         isn->is_v);
 999                 }
1000
1001                 fr->fr_ref = 0;
1002                 fr->fr_dsize = 0;
1003                 fr->fr_data = NULL;
1004                 fr->fr_type = FR_T_NONE;
1005
1006                 (void) ipf_resolvedest(softc, fr->fr_names, &fr->fr_tifs[0],
1007                                 fr->fr_family);
1008                 (void) ipf_resolvedest(softc, fr->fr_names, &fr->fr_tifs[1],
1009                                 fr->fr_family);
1010                 (void) ipf_resolvedest(softc, fr->fr_names, &fr->fr_dif,
1011                                 fr->fr_family);
1012
1013                 /*
1014                  * send a copy back to userland of what we ended up
1015                  * to allow for verification.
1016                  */
1017                 error = ipf_outobj(softc, data, &ips, IPFOBJ_STATESAVE);
1018                 if (error != 0) {
1019                         KFREE(isn);
1020                         MUTEX_DESTROY(&fr->fr_lock);
1021                         KFREE(fr);
1022                         IPFERROR(100025);
1023                         return EFAULT;
1024                 }
1025                 READ_ENTER(&softc->ipf_state);
1026                 error = ipf_state_insert(softc, isn, 0);
1027                 MUTEX_EXIT(&isn->is_lock);
1028                 RWLOCK_EXIT(&softc->ipf_state);
1029
1030         } else {
1031                 READ_ENTER(&softc->ipf_state);
1032                 for (is = softs->ipf_state_list; is; is = is->is_next)
1033                         if (is->is_rule == fr) {
1034                                 error = ipf_state_insert(softc, isn, 0);
1035                                 MUTEX_EXIT(&isn->is_lock);
1036                                 break;
1037                         }
1038
1039                 if (is == NULL) {
1040                         KFREE(isn);
1041                         isn = NULL;
1042                 }
1043                 RWLOCK_EXIT(&softc->ipf_state);
1044
1045                 if (isn == NULL) {
1046                         IPFERROR(100033);
1047                         error = ESRCH;
1048                 }
1049         }
1050
1051         return error;
1052 }
1053
1054
1055 /* ------------------------------------------------------------------------ */
1056 /* Function:    ipf_state_insert                                            */
1057 /* Returns:     int    - 0 == success, -1 == failure                        */
1058 /* Parameters:  softc(I) - pointer to soft context main structure           */
1059 /* Parameters:  is(I)    - pointer to state structure                       */
1060 /*              rev(I) - flag indicating direction of packet                */
1061 /*                                                                          */
1062 /* Inserts a state structure into the hash table (for lookups) and the list */
1063 /* of state entries (for enumeration).  Resolves all of the interface names */
1064 /* to pointers and adjusts running stats for the hash table as appropriate. */
1065 /*                                                                          */
1066 /* This function can fail if the filter rule has had a population policy of */
1067 /* IP addresses used with stateful filtering assigned to it.                */
1068 /*                                                                          */
1069 /* Locking: it is assumed that some kind of lock on ipf_state is held.      */
1070 /*          Exits with is_lock initialised and held - *EVEN IF ERROR*.      */
1071 /* ------------------------------------------------------------------------ */
1072 int
1073 ipf_state_insert(softc, is, rev)
1074         ipf_main_softc_t *softc;
1075         ipstate_t *is;
1076         int rev;
1077 {
1078         ipf_state_softc_t *softs = softc->ipf_state_soft;
1079         frentry_t *fr;
1080         u_int hv;
1081         int i;
1082
1083         /*
1084          * Look up all the interface names in the state entry.
1085          */
1086         for (i = 0; i < 4; i++) {
1087                 if (is->is_ifp[i] != NULL)
1088                         continue;
1089                 is->is_ifp[i] = ipf_resolvenic(softc, is->is_ifname[i],
1090                                                is->is_v);
1091         }
1092
1093         /*
1094          * If we could trust is_hv, then the modulus would not be needed,
1095          * but when running with IPFILTER_SYNC, this stops bad values.
1096          */
1097         hv = is->is_hv % softs->ipf_state_size;
1098         /* TRACE is, hv */
1099         is->is_hv = hv;
1100
1101         /*
1102          * We need to get both of these locks...the first because it is
1103          * possible that once the insert is complete another packet might
1104          * come along, match the entry and want to update it.
1105          */
1106         MUTEX_INIT(&is->is_lock, "ipf state entry");
1107         MUTEX_ENTER(&is->is_lock);
1108         MUTEX_ENTER(&softs->ipf_stinsert);
1109
1110         fr = is->is_rule;
1111         if (fr != NULL) {
1112                 if ((fr->fr_srctrack.ht_max_nodes != 0) &&
1113                     (ipf_ht_node_add(softc, &fr->fr_srctrack,
1114                                      is->is_family, &is->is_src) == -1)) {
1115                         SBUMPD(ipf_state_stats, iss_max_track);
1116                         MUTEX_EXIT(&softs->ipf_stinsert);
1117                         return -1;
1118                 }
1119
1120                 MUTEX_ENTER(&fr->fr_lock);
1121                 fr->fr_ref++;
1122                 MUTEX_EXIT(&fr->fr_lock);
1123                 fr->fr_statecnt++;
1124         }
1125
1126         if (is->is_flags & (SI_WILDP|SI_WILDA)) {
1127                 DT(iss_wild_plus_one);
1128                 SINCL(ipf_state_stats.iss_wild);
1129         }
1130
1131         SBUMP(ipf_state_stats.iss_proto[is->is_p]);
1132         SBUMP(ipf_state_stats.iss_active_proto[is->is_p]);
1133
1134         /*
1135          * add into list table.
1136          */
1137         if (softs->ipf_state_list != NULL)
1138                 softs->ipf_state_list->is_pnext = &is->is_next;
1139         is->is_pnext = &softs->ipf_state_list;
1140         is->is_next = softs->ipf_state_list;
1141         softs->ipf_state_list = is;
1142
1143         if (softs->ipf_state_table[hv] != NULL)
1144                 softs->ipf_state_table[hv]->is_phnext = &is->is_hnext;
1145         else
1146                 softs->ipf_state_stats.iss_inuse++;
1147         is->is_phnext = softs->ipf_state_table + hv;
1148         is->is_hnext = softs->ipf_state_table[hv];
1149         softs->ipf_state_table[hv] = is;
1150         softs->ipf_state_stats.iss_bucketlen[hv]++;
1151         softs->ipf_state_stats.iss_active++;
1152         MUTEX_EXIT(&softs->ipf_stinsert);
1153
1154         ipf_state_setqueue(softc, is, rev);
1155
1156         return 0;
1157 }
1158
1159
1160 /* ------------------------------------------------------------------------ */
1161 /* Function:    ipf_state_matchipv4addrs                                    */
1162 /* Returns:     int - 2 addresses match (strong match), 1 reverse match,    */
1163 /*                    0 no match                                            */
1164 /* Parameters:  is1, is2 pointers to states we are checking                 */
1165 /*                                                                          */
1166 /* Function matches IPv4 addresses it returns strong match for ICMP proto   */
1167 /* even there is only reverse match                                         */
1168 /* ------------------------------------------------------------------------ */
1169 static int
1170 ipf_state_matchipv4addrs(is1, is2)
1171         ipstate_t *is1, *is2;
1172 {
1173         int     rv;
1174
1175         if (is1->is_saddr == is2->is_saddr && is1->is_daddr == is2->is_daddr)
1176                 rv = 2;
1177         else if (is1->is_saddr == is2->is_daddr &&
1178             is1->is_daddr == is2->is_saddr) {
1179                 /* force strong match for ICMP protocol */
1180                 rv = (is1->is_p == IPPROTO_ICMP) ? 2 : 1;
1181         }
1182         else
1183                 rv = 0;
1184
1185         return (rv);
1186 }
1187
1188
1189 /* ------------------------------------------------------------------------ */
1190 /* Function:    ipf_state_matchipv6addrs                                    */
1191 /* Returns:     int - 2 addresses match (strong match), 1 reverse match,    */
1192 /*                    0 no match                                            */
1193 /* Parameters:  is1, is2 pointers to states we are checking                 */
1194 /*                                                                          */
1195 /* Function matches IPv6 addresses it returns strong match for ICMP proto   */
1196 /* even there is only reverse match                                         */
1197 /* ------------------------------------------------------------------------ */
1198 static int
1199 ipf_state_matchipv6addrs(is1, is2)
1200         ipstate_t *is1, *is2;
1201 {
1202         int     rv;
1203
1204         if (IP6_EQ(&is1->is_src, &is2->is_src) &&
1205             IP6_EQ(&is1->is_dst, &is2->is_dst))
1206                 rv = 2;
1207         else if (IP6_EQ(&is1->is_src, &is2->is_dst) &&
1208             IP6_EQ(&is1->is_dst, &is2->is_src)) {
1209                 /* force strong match for ICMPv6 protocol */
1210                 rv = (is1->is_p == IPPROTO_ICMPV6) ? 2 : 1;
1211         }
1212         else
1213                 rv = 0;
1214
1215         return (rv);
1216 }
1217
1218
1219 /* ------------------------------------------------------------------------ */
1220 /* Function:    ipf_state_matchaddresses                                    */
1221 /* Returns:     int - 2 addresses match, 1 reverse match, zero no match     */
1222 /* Parameters:  is1, is2 pointers to states we are checking                 */
1223 /*                                                                          */
1224 /* function retruns true if two pairs of addresses belong to single         */
1225 /* connection. suppose there are two endpoints:                             */
1226 /*      endpoint1 1.1.1.1                                                   */
1227 /*      endpoint2 1.1.1.2                                                   */
1228 /*                                                                          */
1229 /* the state is established by packet flying from .1 to .2 so we see:       */
1230 /*      is1->src = 1.1.1.1                                                  */
1231 /*      is1->dst = 1.1.1.2                                                  */
1232 /* now endpoint 1.1.1.2 sends answer                                        */
1233 /* retreives is1 record created by first packat and compares it with is2    */
1234 /* temporal record, is2 is initialized as follows:                          */
1235 /*      is2->src = 1.1.1.2                                                  */
1236 /*      is2->dst = 1.1.1.1                                                  */
1237 /* in this case 1 will be returned                                          */
1238 /*                                                                          */
1239 /* the ipf_matchaddresses() assumes those two records to be same. of course */
1240 /* the ipf_matchaddresses() also assume records are same in case you pass   */
1241 /* identical arguments (i.e. ipf_matchaddress(is1, is1) would return 2      */
1242 /* ------------------------------------------------------------------------ */
1243 static int
1244 ipf_state_matchaddresses(is1, is2)
1245         ipstate_t *is1, *is2;
1246 {
1247         int     rv;
1248
1249         if (is1->is_v == 4) {
1250                 rv = ipf_state_matchipv4addrs(is1, is2);
1251         }
1252         else {
1253                 rv = ipf_state_matchipv6addrs(is1, is2);
1254         }
1255
1256         return (rv);
1257 }
1258
1259
1260 /* ------------------------------------------------------------------------ */
1261 /* Function:    ipf_matchports                                              */
1262 /* Returns:     int - 2 match, 1 rverse match, 0 no match                   */
1263 /* Parameters:  ppairs1, ppairs - src, dst ports we want to match           */
1264 /*                                                                          */
1265 /* performs the same match for isps members as for addresses                */
1266 /* ------------------------------------------------------------------------ */
1267 static int
1268 ipf_state_matchports(ppairs1, ppairs2)
1269         udpinfo_t *ppairs1, *ppairs2;
1270 {
1271         int     rv;
1272
1273         if (ppairs1->us_sport == ppairs2->us_sport &&
1274             ppairs1->us_dport == ppairs2->us_dport)
1275                 rv = 2;
1276         else if (ppairs1->us_sport == ppairs2->us_dport &&
1277                     ppairs1->us_dport == ppairs2->us_sport)
1278                 rv = 1;
1279         else
1280                 rv = 0;
1281
1282         return (rv);
1283 }
1284
1285
1286 /* ------------------------------------------------------------------------ */
1287 /* Function:    ipf_matchisps                                               */
1288 /* Returns:     int - nonzero if isps members match, 0 nomatch              */
1289 /* Parameters:  is1, is2 - states we want to match                          */
1290 /*                                                                          */
1291 /* performs the same match for isps members as for addresses                */
1292 /* ------------------------------------------------------------------------ */
1293 static int
1294 ipf_state_matchisps(is1, is2)
1295         ipstate_t *is1, *is2;
1296 {
1297         int     rv;
1298
1299         if (is1->is_p == is2->is_p) {
1300                 switch (is1->is_p)
1301                 {
1302                 case IPPROTO_TCP :
1303                 case IPPROTO_UDP :
1304                 case IPPROTO_GRE :
1305                         /* greinfo_t can be also interprted as port pair */
1306                         rv = ipf_state_matchports(&is1->is_ps.is_us,
1307                                                   &is2->is_ps.is_us);
1308                         break;
1309
1310                 case IPPROTO_ICMP :
1311                 case IPPROTO_ICMPV6 :
1312                         /* force strong match for ICMP datagram. */
1313                         if (bcmp(&is1->is_ps, &is2->is_ps,
1314                                  sizeof(icmpinfo_t)) == 0)  {
1315                                 rv = 2;
1316                         } else {
1317                                 rv = 0;
1318                         }
1319                         break;
1320
1321                 default:
1322                         rv = 0;
1323                 }
1324         } else {
1325                 rv = 0;
1326         }
1327
1328         return (rv);
1329 }
1330
1331
1332 /* ------------------------------------------------------------------------ */
1333 /* Function:    ipf_state_match                                             */
1334 /* Returns:     int - nonzero match, zero no match                          */
1335 /* Parameters:  is1, is2 - states we want to match                          */
1336 /*                                                                          */
1337 /* ------------------------------------------------------------------------ */
1338 static int
1339 ipf_state_match(is1, is2)
1340         ipstate_t *is1, *is2;
1341 {
1342         int     rv;
1343         int     amatch;
1344         int     pomatch;
1345
1346         if (bcmp(&is1->is_pass, &is2->is_pass,
1347                  offsetof(struct ipstate, is_authmsk) -
1348                  offsetof(struct ipstate, is_pass)) == 0) {
1349
1350                 pomatch = ipf_state_matchisps(is1, is2);
1351                 amatch = ipf_state_matchaddresses(is1, is2);
1352                 rv = (amatch != 0) && (amatch == pomatch);
1353         } else {
1354                 rv = 0;
1355         }
1356
1357         return (rv);
1358 }
1359
1360 /* ------------------------------------------------------------------------ */
1361 /* Function:    ipf_state_add                                               */
1362 /* Returns:     ipstate_t - 0 = success                                     */
1363 /* Parameters:  softc(I)  - pointer to soft context main structure          */
1364 /*              fin(I)    - pointer to packet information                   */
1365 /*              stsave(O) - pointer to place to save pointer to created     */
1366 /*                          state structure.                                */
1367 /*              flags(I)  - flags to use when creating the structure        */
1368 /*                                                                          */
1369 /* Creates a new IP state structure from the packet information collected.  */
1370 /* Inserts it into the state table and appends to the bottom of the active  */
1371 /* list.  If the capacity of the table has reached the maximum allowed then */
1372 /* the call will fail and a flush is scheduled for the next timeout call.   */
1373 /*                                                                          */
1374 /* NOTE: The use of stsave to point to nat_state will result in memory      */
1375 /*       corruption.  It should only be used to point to objects that will  */
1376 /*       either outlive this (not expired) or will deref the ip_state_t     */
1377 /*       when they are deleted.                                             */
1378 /* ------------------------------------------------------------------------ */
1379 int
1380 ipf_state_add(softc, fin, stsave, flags)
1381         ipf_main_softc_t *softc;
1382         fr_info_t *fin;
1383         ipstate_t **stsave;
1384         u_int flags;
1385 {
1386         ipf_state_softc_t *softs = softc->ipf_state_soft;
1387         ipstate_t *is, ips;
1388         struct icmp *ic;
1389         u_int pass, hv;
1390         frentry_t *fr;
1391         tcphdr_t *tcp;
1392         frdest_t *fdp;
1393         int out;
1394
1395         /*
1396          * If a locally created packet is trying to egress but it
1397          * does not match because of this lock, it is likely that
1398          * the policy will block it and return network unreachable further
1399          * up the stack. To mitigate this error, EAGAIN is returned instead,
1400          * telling the IP stack to try sending this packet again later.
1401          */
1402         if (softs->ipf_state_lock) {
1403                 SBUMPD(ipf_state_stats, iss_add_locked);
1404                 fin->fin_error = EAGAIN;
1405                 return -1;
1406         }
1407
1408         if (fin->fin_flx & (FI_SHORT|FI_STATE|FI_FRAGBODY|FI_BAD)) {
1409                 SBUMPD(ipf_state_stats, iss_add_bad);
1410                 return -1;
1411         }
1412
1413         if ((fin->fin_flx & FI_OOW) && !(fin->fin_tcpf & TH_SYN)) {
1414                 SBUMPD(ipf_state_stats, iss_add_oow);
1415                 return -1;
1416         }
1417
1418         if ((softs->ipf_state_stats.iss_active * 100 / softs->ipf_state_max) >
1419             softs->ipf_state_wm_high) {
1420                 softs->ipf_state_doflush = 1;
1421         }
1422
1423         /*
1424          * If a "keep state" rule has reached the maximum number of references
1425          * to it, then schedule an automatic flush in case we can clear out
1426          * some "dead old wood".  Note that because the lock isn't held on
1427          * fr it is possible that we could overflow.  The cost of overflowing
1428          * is being ignored here as the number by which it can overflow is
1429          * a product of the number of simultaneous threads that could be
1430          * executing in here, so a limit of 100 won't result in 200, but could
1431          * result in 101 or 102.
1432          */
1433         fr = fin->fin_fr;
1434         if (fr != NULL) {
1435                 if ((softs->ipf_state_stats.iss_active >=
1436                      softs->ipf_state_max) && (fr->fr_statemax == 0)) {
1437                         SBUMPD(ipf_state_stats, iss_max);
1438                         return 1;
1439                 }
1440                 if ((fr->fr_statemax != 0) &&
1441                     (fr->fr_statecnt >= fr->fr_statemax)) {
1442                         SBUMPD(ipf_state_stats, iss_max_ref);
1443                         return 2;
1444                 }
1445         }
1446
1447         is = &ips;
1448         if (fr == NULL) {
1449                 pass = softc->ipf_flags;
1450                 is->is_tag = FR_NOLOGTAG;
1451         } else {
1452                 pass = fr->fr_flags;
1453         }
1454
1455         ic = NULL;
1456         tcp = NULL;
1457         out = fin->fin_out;
1458         bzero((char *)is, sizeof(*is));
1459         is->is_die = 1 + softc->ipf_ticks;
1460         /*
1461          * We want to check everything that is a property of this packet,
1462          * but we don't (automatically) care about its fragment status as
1463          * this may change.
1464          */
1465         is->is_pass = pass;
1466         is->is_v = fin->fin_v;
1467         is->is_sec = fin->fin_secmsk;
1468         is->is_secmsk = 0xffff;
1469         is->is_auth = fin->fin_auth;
1470         is->is_authmsk = 0xffff;
1471         is->is_family = fin->fin_family;
1472         is->is_opt[0] = fin->fin_optmsk;
1473         is->is_optmsk[0] = 0xffffffff;
1474         if (is->is_v == 6) {
1475                 is->is_opt[0] &= ~0x8;
1476                 is->is_optmsk[0] &= ~0x8;
1477         }
1478
1479         /*
1480          * Copy and calculate...
1481          */
1482         hv = (is->is_p = fin->fin_fi.fi_p);
1483         is->is_src = fin->fin_fi.fi_src;
1484         hv += is->is_saddr;
1485         is->is_dst = fin->fin_fi.fi_dst;
1486         hv += is->is_daddr;
1487 #ifdef  USE_INET6
1488         if (fin->fin_v == 6) {
1489                 /*
1490                  * For ICMPv6, we check to see if the destination address is
1491                  * a multicast address.  If it is, do not include it in the
1492                  * calculation of the hash because the correct reply will come
1493                  * back from a real address, not a multicast address.
1494                  */
1495                 if ((is->is_p == IPPROTO_ICMPV6) &&
1496                     IN6_IS_ADDR_MULTICAST(&is->is_dst.in6)) {
1497                         /*
1498                          * So you can do keep state with neighbour discovery.
1499                          *
1500                          * Here we could use the address from the neighbour
1501                          * solicit message to put in the state structure and
1502                          * we could use that without a wildcard flag too...
1503                          */
1504                         flags |= SI_W_DADDR;
1505                         hv -= is->is_daddr;
1506                 } else {
1507                         hv += is->is_dst.i6[1];
1508                         hv += is->is_dst.i6[2];
1509                         hv += is->is_dst.i6[3];
1510                 }
1511                 hv += is->is_src.i6[1];
1512                 hv += is->is_src.i6[2];
1513                 hv += is->is_src.i6[3];
1514         }
1515 #endif
1516         if ((fin->fin_v == 4) &&
1517             (fin->fin_flx & (FI_MULTICAST|FI_BROADCAST|FI_MBCAST))) {
1518                 flags |= SI_W_DADDR;
1519                 hv -= is->is_daddr;
1520         }
1521
1522         switch (is->is_p)
1523         {
1524 #ifdef  USE_INET6
1525         case IPPROTO_ICMPV6 :
1526                 ic = fin->fin_dp;
1527
1528                 switch (ic->icmp_type)
1529                 {
1530                 case ICMP6_ECHO_REQUEST :
1531                         hv += (is->is_icmp.ici_id = ic->icmp_id);
1532                         /*FALLTHROUGH*/
1533                 case ICMP6_MEMBERSHIP_QUERY :
1534                 case ND_ROUTER_SOLICIT :
1535                 case ND_NEIGHBOR_SOLICIT :
1536                 case ICMP6_NI_QUERY :
1537                         is->is_icmp.ici_type = ic->icmp_type;
1538                         break;
1539                 default :
1540                         SBUMPD(ipf_state_stats, iss_icmp6_notquery);
1541                         return -2;
1542                 }
1543                 break;
1544 #endif
1545         case IPPROTO_ICMP :
1546                 ic = fin->fin_dp;
1547
1548                 switch (ic->icmp_type)
1549                 {
1550                 case ICMP_ECHO :
1551                 case ICMP_TSTAMP :
1552                 case ICMP_IREQ :
1553                 case ICMP_MASKREQ :
1554                         is->is_icmp.ici_type = ic->icmp_type;
1555                         hv += (is->is_icmp.ici_id = ic->icmp_id);
1556                         break;
1557                 default :
1558                         SBUMPD(ipf_state_stats, iss_icmp_notquery);
1559                         return -3;
1560                 }
1561                 break;
1562
1563 #if 0
1564         case IPPROTO_GRE :
1565                 gre = fin->fin_dp;
1566
1567                 is->is_gre.gs_flags = gre->gr_flags;
1568                 is->is_gre.gs_ptype = gre->gr_ptype;
1569                 if (GRE_REV(is->is_gre.gs_flags) == 1) {
1570                         is->is_call[0] = fin->fin_data[0];
1571                         is->is_call[1] = fin->fin_data[1];
1572                 }
1573                 break;
1574 #endif
1575
1576         case IPPROTO_TCP :
1577                 tcp = fin->fin_dp;
1578
1579                 if (tcp->th_flags & TH_RST) {
1580                         SBUMPD(ipf_state_stats, iss_tcp_rstadd);
1581                         return -4;
1582                 }
1583
1584                 /* TRACE is, flags, hv */
1585
1586                 /*
1587                  * The endian of the ports doesn't matter, but the ack and
1588                  * sequence numbers do as we do mathematics on them later.
1589                  */
1590                 is->is_sport = htons(fin->fin_data[0]);
1591                 is->is_dport = htons(fin->fin_data[1]);
1592                 if ((flags & (SI_W_DPORT|SI_W_SPORT)) == 0) {
1593                         hv += is->is_sport;
1594                         hv += is->is_dport;
1595                 }
1596
1597                 /* TRACE is, flags, hv */
1598
1599                 /*
1600                  * If this is a real packet then initialise fields in the
1601                  * state information structure from the TCP header information.
1602                  */
1603
1604                 is->is_maxdwin = 1;
1605                 is->is_maxswin = ntohs(tcp->th_win);
1606                 if (is->is_maxswin == 0)
1607                         is->is_maxswin = 1;
1608
1609                 if ((fin->fin_flx & FI_IGNORE) == 0) {
1610                         is->is_send = ntohl(tcp->th_seq) + fin->fin_dlen -
1611                                       (TCP_OFF(tcp) << 2) +
1612                                       ((tcp->th_flags & TH_SYN) ? 1 : 0) +
1613                                       ((tcp->th_flags & TH_FIN) ? 1 : 0);
1614                         is->is_maxsend = is->is_send;
1615
1616                         /*
1617                          * Window scale option is only present in
1618                          * SYN/SYN-ACK packet.
1619                          */
1620                         if ((tcp->th_flags & ~(TH_FIN|TH_ACK|TH_ECNALL)) ==
1621                             TH_SYN &&
1622                             (TCP_OFF(tcp) > (sizeof(tcphdr_t) >> 2))) {
1623                                 if (ipf_tcpoptions(softs, fin, tcp,
1624                                               &is->is_tcp.ts_data[0]) == -1)
1625                                         fin->fin_flx |= FI_BAD;
1626                         }
1627
1628                         if ((fin->fin_out != 0) && (pass & FR_NEWISN) != 0) {
1629                                 ipf_checknewisn(fin, is);
1630                                 ipf_fixoutisn(fin, is);
1631                         }
1632
1633                         if ((tcp->th_flags & TH_OPENING) == TH_SYN)
1634                                 flags |= IS_TCPFSM;
1635                         else {
1636                                 is->is_maxdwin = is->is_maxswin * 2;
1637                                 is->is_dend = ntohl(tcp->th_ack);
1638                                 is->is_maxdend = ntohl(tcp->th_ack);
1639                                 is->is_maxdwin *= 2;
1640                         }
1641                 }
1642
1643                 /*
1644                  * If we're creating state for a starting connection, start
1645                  * the timer on it as we'll never see an error if it fails
1646                  * to connect.
1647                  */
1648                 break;
1649
1650         case IPPROTO_UDP :
1651                 tcp = fin->fin_dp;
1652
1653                 is->is_sport = htons(fin->fin_data[0]);
1654                 is->is_dport = htons(fin->fin_data[1]);
1655                 if ((flags & (SI_W_DPORT|SI_W_SPORT)) == 0) {
1656                         hv += tcp->th_dport;
1657                         hv += tcp->th_sport;
1658                 }
1659                 break;
1660
1661         default :
1662                 break;
1663         }
1664         hv = DOUBLE_HASH(hv);
1665         is->is_hv = hv;
1666
1667         /*
1668          * Look for identical state.
1669          */
1670         for (is = softs->ipf_state_table[hv % softs->ipf_state_size];
1671              is != NULL; is = is->is_hnext) {
1672                 if (ipf_state_match(&ips, is) == 1)
1673                         break;
1674         }
1675         if (is != NULL) {
1676                 SBUMPD(ipf_state_stats, iss_add_dup);
1677                 return 3;
1678         }
1679
1680         if (softs->ipf_state_stats.iss_bucketlen[hv] >=
1681             softs->ipf_state_maxbucket) {
1682                 SBUMPD(ipf_state_stats, iss_bucket_full);
1683                 return 4;
1684         }
1685
1686         /*
1687          * No existing state; create new
1688          */
1689         KMALLOC(is, ipstate_t *);
1690         if (is == NULL) {
1691                 SBUMPD(ipf_state_stats, iss_nomem);
1692                 return 5;
1693         }
1694         bcopy((char *)&ips, (char *)is, sizeof(*is));
1695         is->is_flags = flags & IS_INHERITED;
1696         is->is_rulen = fin->fin_rule;
1697         is->is_rule = fr;
1698
1699         /*
1700          * Do not do the modulus here, it is done in ipf_state_insert().
1701          */
1702         if (fr != NULL) {
1703                 ipftq_t *tq;
1704
1705                 (void) strncpy(is->is_group, FR_NAME(fr, fr_group),
1706                                FR_GROUPLEN);
1707                 if (fr->fr_age[0] != 0) {
1708                         tq = ipf_addtimeoutqueue(softc,
1709                                                  &softs->ipf_state_usertq,
1710                                                  fr->fr_age[0]);
1711                         is->is_tqehead[0] = tq;
1712                         is->is_sti.tqe_flags |= TQE_RULEBASED;
1713                 }
1714                 if (fr->fr_age[1] != 0) {
1715                         tq = ipf_addtimeoutqueue(softc,
1716                                                  &softs->ipf_state_usertq,
1717                                                  fr->fr_age[1]);
1718                         is->is_tqehead[1] = tq;
1719                         is->is_sti.tqe_flags |= TQE_RULEBASED;
1720                 }
1721
1722                 is->is_tag = fr->fr_logtag;
1723         }
1724
1725         /*
1726          * It may seem strange to set is_ref to 2, but if stsave is not NULL
1727          * then a copy of the pointer is being stored somewhere else and in
1728          * the end, it will expect to be able to do something with it.
1729          */
1730         is->is_me = stsave;
1731         if (stsave != NULL) {
1732                 *stsave = is;
1733                 is->is_ref = 2;
1734         } else {
1735                 is->is_ref = 1;
1736         }
1737         is->is_pkts[0] = 0, is->is_bytes[0] = 0;
1738         is->is_pkts[1] = 0, is->is_bytes[1] = 0;
1739         is->is_pkts[2] = 0, is->is_bytes[2] = 0;
1740         is->is_pkts[3] = 0, is->is_bytes[3] = 0;
1741         if ((fin->fin_flx & FI_IGNORE) == 0) {
1742                 is->is_pkts[out] = 1;
1743                 fin->fin_pktnum = 1;
1744                 is->is_bytes[out] = fin->fin_plen;
1745                 is->is_flx[out][0] = fin->fin_flx & FI_CMP;
1746                 is->is_flx[out][0] &= ~FI_OOW;
1747         }
1748
1749         if (pass & FR_STLOOSE)
1750                 is->is_flags |= IS_LOOSE;
1751
1752         if (pass & FR_STSTRICT)
1753                 is->is_flags |= IS_STRICT;
1754
1755         if (pass & FR_STATESYNC)
1756                 is->is_flags |= IS_STATESYNC;
1757
1758         if (pass & FR_LOGFIRST)
1759                 is->is_pass &= ~(FR_LOGFIRST|FR_LOG);
1760
1761         READ_ENTER(&softc->ipf_state);
1762
1763         if (ipf_state_insert(softc, is, fin->fin_rev) == -1) {
1764                 RWLOCK_EXIT(&softc->ipf_state);
1765                 /*
1766                  * This is a bit more manual than it should be but
1767                  * ipf_state_del cannot be called.
1768                  */
1769                 MUTEX_EXIT(&is->is_lock);
1770                 MUTEX_DESTROY(&is->is_lock);
1771                 if (is->is_tqehead[0] != NULL) {
1772                         if (ipf_deletetimeoutqueue(is->is_tqehead[0]) == 0)
1773                                 ipf_freetimeoutqueue(softc, is->is_tqehead[0]);
1774                         is->is_tqehead[0] = NULL;
1775                 }
1776                 if (is->is_tqehead[1] != NULL) {
1777                         if (ipf_deletetimeoutqueue(is->is_tqehead[1]) == 0)
1778                                 ipf_freetimeoutqueue(softc, is->is_tqehead[1]);
1779                         is->is_tqehead[1] = NULL;
1780                 }
1781                 KFREE(is);
1782                 return -1;
1783         }
1784
1785         /*
1786          * Filling in the interface name is after the insert so that an
1787          * event (such as add/delete) of an interface that is referenced
1788          * by this rule will see this state entry.
1789          */
1790         if (fr != NULL) {
1791                 /*
1792                  * The name '-' is special for network interfaces and causes
1793                  * a NULL name to be present, always, allowing packets to
1794                  * match it, regardless of their interface.
1795                  */
1796                 if ((fin->fin_ifp == NULL) ||
1797                     (fr->fr_ifnames[out << 1] != -1 &&
1798                      fr->fr_names[fr->fr_ifnames[out << 1] + 0] == '-' &&
1799                      fr->fr_names[fr->fr_ifnames[out << 1] + 1] == '\0')) {
1800                         is->is_ifp[out << 1] = fr->fr_ifas[0];
1801                         strncpy(is->is_ifname[out << 1],
1802                                 fr->fr_names + fr->fr_ifnames[0],
1803                                 sizeof(fr->fr_ifnames[0]));
1804                 } else {
1805                         is->is_ifp[out << 1] = fin->fin_ifp;
1806                         COPYIFNAME(fin->fin_v, fin->fin_ifp,
1807                                    is->is_ifname[out << 1]);
1808                 }
1809
1810                 is->is_ifp[(out << 1) + 1] = fr->fr_ifas[1];
1811                 if (fr->fr_ifnames[1] != -1) {
1812                         strncpy(is->is_ifname[(out << 1) + 1],
1813                                 fr->fr_names + fr->fr_ifnames[1],
1814                                 sizeof(fr->fr_ifnames[1]));
1815                 }
1816
1817                 is->is_ifp[(1 - out) << 1] = fr->fr_ifas[2];
1818                 if (fr->fr_ifnames[2] != -1) {
1819                         strncpy(is->is_ifname[((1 - out) << 1)],
1820                                 fr->fr_names + fr->fr_ifnames[2],
1821                                 sizeof(fr->fr_ifnames[2]));
1822                 }
1823
1824                 is->is_ifp[((1 - out) << 1) + 1] = fr->fr_ifas[3];
1825                 if (fr->fr_ifnames[3] != -1) {
1826                         strncpy(is->is_ifname[((1 - out) << 1) + 1],
1827                                 fr->fr_names + fr->fr_ifnames[3],
1828                                 sizeof(fr->fr_ifnames[3]));
1829                 }
1830         } else {
1831                 if (fin->fin_ifp != NULL) {
1832                         is->is_ifp[out << 1] = fin->fin_ifp;
1833                         COPYIFNAME(fin->fin_v, fin->fin_ifp,
1834                                    is->is_ifname[out << 1]);
1835                 }
1836         }
1837
1838         if (fin->fin_p == IPPROTO_TCP) {
1839                 /*
1840                 * If we're creating state for a starting connection, start the
1841                 * timer on it as we'll never see an error if it fails to
1842                 * connect.
1843                 */
1844                 (void) ipf_tcp_age(&is->is_sti, fin, softs->ipf_state_tcptq,
1845                                    is->is_flags, 2);
1846         }
1847         MUTEX_EXIT(&is->is_lock);
1848         if ((is->is_flags & IS_STATESYNC) && ((is->is_flags & SI_CLONE) == 0))
1849                 is->is_sync = ipf_sync_new(softc, SMC_STATE, fin, is);
1850         if (softs->ipf_state_logging)
1851                 ipf_state_log(softc, is, ISL_NEW);
1852
1853         RWLOCK_EXIT(&softc->ipf_state);
1854
1855         fin->fin_flx |= FI_STATE;
1856         if (fin->fin_flx & FI_FRAG)
1857                 (void) ipf_frag_new(softc, fin, pass);
1858
1859         fdp = &fr->fr_tifs[0];
1860         if (fdp->fd_type == FRD_DSTLIST) {
1861                 ipf_dstlist_select_node(fin, fdp->fd_ptr, NULL,
1862                                         &is->is_tifs[0]);
1863         } else {
1864                 bcopy(fdp, &is->is_tifs[0], sizeof(*fdp));
1865         }
1866
1867         fdp = &fr->fr_tifs[1];
1868         if (fdp->fd_type == FRD_DSTLIST) {
1869                 ipf_dstlist_select_node(fin, fdp->fd_ptr, NULL,
1870                                         &is->is_tifs[1]);
1871         } else {
1872                 bcopy(fdp, &is->is_tifs[1], sizeof(*fdp));
1873         }
1874         fin->fin_tif = &is->is_tifs[fin->fin_rev];
1875
1876         fdp = &fr->fr_dif;
1877         if (fdp->fd_type == FRD_DSTLIST) {
1878                 ipf_dstlist_select_node(fin, fdp->fd_ptr, NULL,
1879                                         &is->is_dif);
1880         } else {
1881                 bcopy(fdp, &is->is_dif, sizeof(*fdp));
1882         }
1883         fin->fin_dif = &is->is_dif;
1884
1885         return 0;
1886 }
1887
1888
1889 /* ------------------------------------------------------------------------ */
1890 /* Function:    ipf_tcpoptions                                              */
1891 /* Returns:     int - 1 == packet matches state entry, 0 == it does not,    */
1892 /*                   -1 == packet has bad TCP options data                  */
1893 /* Parameters:  softs(I) - pointer to state context structure               */
1894 /*              fin(I) - pointer to packet information                      */
1895 /*              tcp(I) - pointer to TCP packet header                       */
1896 /*              td(I)  - pointer to TCP data held as part of the state      */
1897 /*                                                                          */
1898 /* Look after the TCP header for any options and deal with those that are   */
1899 /* present.  Record details about those that we recogise.                   */
1900 /* ------------------------------------------------------------------------ */
1901 static int
1902 ipf_tcpoptions(softs, fin, tcp, td)
1903         ipf_state_softc_t *softs;
1904         fr_info_t *fin;
1905         tcphdr_t *tcp;
1906         tcpdata_t *td;
1907 {
1908         int off, mlen, ol, i, len, retval;
1909         char buf[64], *s, opt;
1910         mb_t *m = NULL;
1911
1912         len = (TCP_OFF(tcp) << 2);
1913         if (fin->fin_dlen < len) {
1914                 SBUMPD(ipf_state_stats, iss_tcp_toosmall);
1915                 return 0;
1916         }
1917         len -= sizeof(*tcp);
1918
1919         off = fin->fin_plen - fin->fin_dlen + sizeof(*tcp) + fin->fin_ipoff;
1920
1921         m = fin->fin_m;
1922         mlen = MSGDSIZE(m) - off;
1923         if (len > mlen) {
1924                 len = mlen;
1925                 retval = 0;
1926         } else {
1927                 retval = 1;
1928         }
1929
1930         COPYDATA(m, off, len, buf);
1931
1932         for (s = buf; len > 0; ) {
1933                 opt = *s;
1934                 if (opt == TCPOPT_EOL)
1935                         break;
1936                 else if (opt == TCPOPT_NOP)
1937                         ol = 1;
1938                 else {
1939                         if (len < 2)
1940                                 break;
1941                         ol = (int)*(s + 1);
1942                         if (ol < 2 || ol > len)
1943                                 break;
1944
1945                         /*
1946                          * Extract the TCP options we are interested in out of
1947                          * the header and store them in the the tcpdata struct.
1948                          */
1949                         switch (opt)
1950                         {
1951                         case TCPOPT_WINDOW :
1952                                 if (ol == TCPOLEN_WINDOW) {
1953                                         i = (int)*(s + 2);
1954                                         if (i > TCP_WSCALE_MAX)
1955                                                 i = TCP_WSCALE_MAX;
1956                                         else if (i < 0)
1957                                                 i = 0;
1958                                         td->td_winscale = i;
1959                                         td->td_winflags |= TCP_WSCALE_SEEN|
1960                                                            TCP_WSCALE_FIRST;
1961                                 } else
1962                                         retval = -1;
1963                                 break;
1964                         case TCPOPT_MAXSEG :
1965                                 /*
1966                                  * So, if we wanted to set the TCP MAXSEG,
1967                                  * it should be done here...
1968                                  */
1969                                 if (ol == TCPOLEN_MAXSEG) {
1970                                         i = (int)*(s + 2);
1971                                         i <<= 8;
1972                                         i += (int)*(s + 3);
1973                                         td->td_maxseg = i;
1974                                 } else
1975                                         retval = -1;
1976                                 break;
1977                         case TCPOPT_SACK_PERMITTED :
1978                                 if (ol == TCPOLEN_SACK_PERMITTED)
1979                                         td->td_winflags |= TCP_SACK_PERMIT;
1980                                 else
1981                                         retval = -1;
1982                                 break;
1983                         }
1984                 }
1985                 len -= ol;
1986                 s += ol;
1987         }
1988         if (retval == -1) {
1989                 SBUMPD(ipf_state_stats, iss_tcp_badopt);
1990         }
1991         return retval;
1992 }
1993
1994
1995 /* ------------------------------------------------------------------------ */
1996 /* Function:    ipf_state_tcp                                               */
1997 /* Returns:     int - 1 == packet matches state entry, 0 == it does not     */
1998 /* Parameters:  softc(I)  - pointer to soft context main structure          */
1999 /*              softs(I) - pointer to state context structure               */
2000 /*              fin(I)   - pointer to packet information                    */
2001 /*              tcp(I)   - pointer to TCP packet header                     */
2002 /*              is(I)  - pointer to master state structure                  */
2003 /*                                                                          */
2004 /* Check to see if a packet with TCP headers fits within the TCP window.    */
2005 /* Change timeout depending on whether new packet is a SYN-ACK returning    */
2006 /* for a SYN or a RST or FIN which indicate time to close up shop.          */
2007 /* ------------------------------------------------------------------------ */
2008 static int
2009 ipf_state_tcp(softc, softs, fin, tcp, is)
2010         ipf_main_softc_t *softc;
2011         ipf_state_softc_t *softs;
2012         fr_info_t *fin;
2013         tcphdr_t *tcp;
2014         ipstate_t *is;
2015 {
2016         tcpdata_t  *fdata, *tdata;
2017         int source, ret, flags;
2018
2019         source = !fin->fin_rev;
2020         if (((is->is_flags & IS_TCPFSM) != 0) && (source == 1) &&
2021             (ntohs(is->is_sport) != fin->fin_data[0]))
2022                 source = 0;
2023         fdata = &is->is_tcp.ts_data[!source];
2024         tdata = &is->is_tcp.ts_data[source];
2025
2026         MUTEX_ENTER(&is->is_lock);
2027
2028         /*
2029          * If a SYN packet is received for a connection that is on the way out
2030          * but hasn't yet departed then advance this session along the way.
2031          */
2032         if ((tcp->th_flags & TH_OPENING) == TH_SYN) {
2033                 if ((is->is_state[0] > IPF_TCPS_ESTABLISHED) &&
2034                     (is->is_state[1] > IPF_TCPS_ESTABLISHED)) {
2035                         is->is_state[!source] = IPF_TCPS_CLOSED;
2036                         ipf_movequeue(softc->ipf_ticks, &is->is_sti,
2037                                       is->is_sti.tqe_ifq,
2038                                       &softs->ipf_state_deletetq);
2039                         MUTEX_EXIT(&is->is_lock);
2040                         DT1(iss_tcp_closing, ipstate_t *, is);
2041                         SBUMP(ipf_state_stats.iss_tcp_closing);
2042                         return 0;
2043                 }
2044         }
2045
2046         if (is->is_flags & IS_LOOSE)
2047                 ret = 1;
2048         else
2049                 ret = ipf_state_tcpinwindow(fin, fdata, tdata, tcp,
2050                                             is->is_flags);
2051         if (ret > 0) {
2052                 /*
2053                  * Nearing end of connection, start timeout.
2054                  */
2055                 ret = ipf_tcp_age(&is->is_sti, fin, softs->ipf_state_tcptq,
2056                                   is->is_flags, ret);
2057                 if (ret == 0) {
2058                         MUTEX_EXIT(&is->is_lock);
2059                         DT2(iss_tcp_fsm, fr_info_t *, fin, ipstate_t *, is);
2060                         SBUMP(ipf_state_stats.iss_tcp_fsm);
2061                         return 0;
2062                 }
2063
2064                 if (softs->ipf_state_logging > 4)
2065                         ipf_state_log(softc, is, ISL_STATECHANGE);
2066
2067                 /*
2068                  * set s0's as appropriate.  Use syn-ack packet as it
2069                  * contains both pieces of required information.
2070                  */
2071                 /*
2072                  * Window scale option is only present in SYN/SYN-ACK packet.
2073                  * Compare with ~TH_FIN to mask out T/TCP setups.
2074                  */
2075                 flags = tcp->th_flags & ~(TH_FIN|TH_ECNALL);
2076                 if (flags == (TH_SYN|TH_ACK)) {
2077                         is->is_s0[source] = ntohl(tcp->th_ack);
2078                         is->is_s0[!source] = ntohl(tcp->th_seq) + 1;
2079                         if ((TCP_OFF(tcp) > (sizeof(tcphdr_t) >> 2))) {
2080                                 if (ipf_tcpoptions(softs, fin, tcp,
2081                                                    fdata) == -1)
2082                                         fin->fin_flx |= FI_BAD;
2083                         }
2084                         if ((fin->fin_out != 0) && (is->is_pass & FR_NEWISN))
2085                                 ipf_checknewisn(fin, is);
2086                 } else if (flags == TH_SYN) {
2087                         is->is_s0[source] = ntohl(tcp->th_seq) + 1;
2088                         if ((TCP_OFF(tcp) > (sizeof(tcphdr_t) >> 2))) {
2089                                 if (ipf_tcpoptions(softs, fin, tcp,
2090                                                    fdata) == -1)
2091                                         fin->fin_flx |= FI_BAD;
2092                         }
2093
2094                         if ((fin->fin_out != 0) && (is->is_pass & FR_NEWISN))
2095                                 ipf_checknewisn(fin, is);
2096
2097                 }
2098                 ret = 1;
2099         } else {
2100                 DT2(iss_tcp_oow, fr_info_t *, fin, ipstate_t *, is);
2101                 SBUMP(ipf_state_stats.iss_tcp_oow);
2102                 ret = 0;
2103         }
2104         MUTEX_EXIT(&is->is_lock);
2105         return ret;
2106 }
2107
2108
2109 /* ------------------------------------------------------------------------ */
2110 /* Function:    ipf_checknewisn                                             */
2111 /* Returns:     Nil                                                         */
2112 /* Parameters:  fin(I)   - pointer to packet information                    */
2113 /*              is(I)  - pointer to master state structure                  */
2114 /*                                                                          */
2115 /* Check to see if this TCP connection is expecting and needs a new         */
2116 /* sequence number for a particular direction of the connection.            */
2117 /*                                                                          */
2118 /* NOTE: This does not actually change the sequence numbers, only gets new  */
2119 /* one ready.                                                               */
2120 /* ------------------------------------------------------------------------ */
2121 static void
2122 ipf_checknewisn(fin, is)
2123         fr_info_t *fin;
2124         ipstate_t *is;
2125 {
2126         u_32_t sumd, old, new;
2127         tcphdr_t *tcp;
2128         int i;
2129
2130         i = fin->fin_rev;
2131         tcp = fin->fin_dp;
2132
2133         if (((i == 0) && !(is->is_flags & IS_ISNSYN)) ||
2134             ((i == 1) && !(is->is_flags & IS_ISNACK))) {
2135                 old = ntohl(tcp->th_seq);
2136                 new = ipf_newisn(fin);
2137                 is->is_isninc[i] = new - old;
2138                 CALC_SUMD(old, new, sumd);
2139                 is->is_sumd[i] = (sumd & 0xffff) + (sumd >> 16);
2140
2141                 is->is_flags |= ((i == 0) ? IS_ISNSYN : IS_ISNACK);
2142         }
2143 }
2144
2145
2146 /* ------------------------------------------------------------------------ */
2147 /* Function:    ipf_state_tcpinwindow                                       */
2148 /* Returns:     int - 1 == packet inside TCP "window", 0 == not inside.     */
2149 /* Parameters:  fin(I)   - pointer to packet information                    */
2150 /*              fdata(I) - pointer to tcp state informatio (forward)        */
2151 /*              tdata(I) - pointer to tcp state informatio (reverse)        */
2152 /*              tcp(I)   - pointer to TCP packet header                     */
2153 /*                                                                          */
2154 /* Given a packet has matched addresses and ports, check to see if it is    */
2155 /* within the TCP data window.  In a show of generosity, allow packets that */
2156 /* are within the window space behind the current sequence # as well.       */
2157 /* ------------------------------------------------------------------------ */
2158 static int
2159 ipf_state_tcpinwindow(fin, fdata, tdata, tcp, flags)
2160         fr_info_t *fin;
2161         tcpdata_t  *fdata, *tdata;
2162         tcphdr_t *tcp;
2163         int flags;
2164 {
2165         ipf_main_softc_t *softc = fin->fin_main_soft;
2166         ipf_state_softc_t *softs = softc->ipf_state_soft;
2167         tcp_seq seq, ack, end;
2168         int ackskew, tcpflags;
2169         u_32_t win, maxwin;
2170         int dsize, inseq;
2171
2172         /*
2173          * Find difference between last checked packet and this packet.
2174          */
2175         tcpflags = tcp->th_flags;
2176         seq = ntohl(tcp->th_seq);
2177         ack = ntohl(tcp->th_ack);
2178         if (tcpflags & TH_SYN)
2179                 win = ntohs(tcp->th_win);
2180         else
2181                 win = ntohs(tcp->th_win) << fdata->td_winscale;
2182
2183         /*
2184          * A window of 0 produces undesirable behaviour from this function.
2185          */
2186         if (win == 0)
2187                 win = 1;
2188
2189         dsize = fin->fin_dlen - (TCP_OFF(tcp) << 2) +
2190                 ((tcpflags & TH_SYN) ? 1 : 0) + ((tcpflags & TH_FIN) ? 1 : 0);
2191
2192         /*
2193          * if window scaling is present, the scaling is only allowed
2194          * for windows not in the first SYN packet. In that packet the
2195          * window is 65535 to specify the largest window possible
2196          * for receivers not implementing the window scale option.
2197          * Currently, we do not assume TTCP here. That means that
2198          * if we see a second packet from a host (after the initial
2199          * SYN), we can assume that the receiver of the SYN did
2200          * already send back the SYN/ACK (and thus that we know if
2201          * the receiver also does window scaling)
2202          */
2203         if (!(tcpflags & TH_SYN) && (fdata->td_winflags & TCP_WSCALE_FIRST)) {
2204                 fdata->td_winflags &= ~TCP_WSCALE_FIRST;
2205                 fdata->td_maxwin = win;
2206         }
2207
2208         end = seq + dsize;
2209
2210         if ((fdata->td_end == 0) &&
2211             (!(flags & IS_TCPFSM) ||
2212              ((tcpflags & TH_OPENING) == TH_OPENING))) {
2213                 /*
2214                  * Must be a (outgoing) SYN-ACK in reply to a SYN.
2215                  */
2216                 fdata->td_end = end - 1;
2217                 fdata->td_maxwin = 1;
2218                 fdata->td_maxend = end + win;
2219         }
2220
2221         if (!(tcpflags & TH_ACK)) {  /* Pretend an ack was sent */
2222                 ack = tdata->td_end;
2223         } else if (((tcpflags & (TH_ACK|TH_RST)) == (TH_ACK|TH_RST)) &&
2224                    (ack == 0)) {
2225                 /* gross hack to get around certain broken tcp stacks */
2226                 ack = tdata->td_end;
2227         }
2228
2229         maxwin = tdata->td_maxwin;
2230         ackskew = tdata->td_end - ack;
2231
2232         /*
2233          * Strict sequencing only allows in-order delivery.
2234          */
2235         if ((flags & IS_STRICT) != 0) {
2236                 if (seq != fdata->td_end) {
2237                         DT2(iss_tcp_struct, tcpdata_t *, fdata, int, seq);
2238                         SBUMP(ipf_state_stats.iss_tcp_strict);
2239                         fin->fin_flx |= FI_OOW;
2240                         return 0;
2241                 }
2242         }
2243
2244 #define SEQ_GE(a,b)     ((int)((a) - (b)) >= 0)
2245 #define SEQ_GT(a,b)     ((int)((a) - (b)) > 0)
2246         inseq = 0;
2247         if ((SEQ_GE(fdata->td_maxend, end)) &&
2248             (SEQ_GE(seq, fdata->td_end - maxwin)) &&
2249 /* XXX what about big packets */
2250 #define MAXACKWINDOW 66000
2251             (-ackskew <= (MAXACKWINDOW)) &&
2252             ( ackskew <= (MAXACKWINDOW << fdata->td_winscale))) {
2253                 inseq = 1;
2254         /*
2255          * Microsoft Windows will send the next packet to the right of the
2256          * window if SACK is in use.
2257          */
2258         } else if ((seq == fdata->td_maxend) && (ackskew == 0) &&
2259             (fdata->td_winflags & TCP_SACK_PERMIT) &&
2260             (tdata->td_winflags & TCP_SACK_PERMIT)) {
2261                 DT2(iss_sinsack, tcpdata_t *, fdata, int, seq);
2262                 SBUMP(ipf_state_stats.iss_winsack);
2263                 inseq = 1;
2264         /*
2265          * Sometimes a TCP RST will be generated with only the ACK field
2266          * set to non-zero.
2267          */
2268         } else if ((seq == 0) && (tcpflags == (TH_RST|TH_ACK)) &&
2269                    (ackskew >= -1) && (ackskew <= 1)) {
2270                 inseq = 1;
2271         } else if (!(flags & IS_TCPFSM)) {
2272                 int i;
2273
2274                 i = (fin->fin_rev << 1) + fin->fin_out;
2275
2276 #if 0
2277                 if (is_pkts[i]0 == 0) {
2278                         /*
2279                          * Picking up a connection in the middle, the "next"
2280                          * packet seen from a direction that is new should be
2281                          * accepted, even if it appears out of sequence.
2282                          */
2283                         inseq = 1;
2284                 } else
2285 #endif
2286                 if (!(fdata->td_winflags &
2287                             (TCP_WSCALE_SEEN|TCP_WSCALE_FIRST))) {
2288                         /*
2289                          * No TCPFSM and no window scaling, so make some
2290                          * extra guesses.
2291                          */
2292                         if ((seq == fdata->td_maxend) && (ackskew == 0))
2293                                 inseq = 1;
2294                         else if (SEQ_GE(seq + maxwin, fdata->td_end - maxwin))
2295                                 inseq = 1;
2296                 }
2297         }
2298
2299         /* TRACE(inseq, fdata, tdata, seq, end, ack, ackskew, win, maxwin) */
2300
2301         if (inseq) {
2302                 /* if ackskew < 0 then this should be due to fragmented
2303                  * packets. There is no way to know the length of the
2304                  * total packet in advance.
2305                  * We do know the total length from the fragment cache though.
2306                  * Note however that there might be more sessions with
2307                  * exactly the same source and destination parameters in the
2308                  * state cache (and source and destination is the only stuff
2309                  * that is saved in the fragment cache). Note further that
2310                  * some TCP connections in the state cache are hashed with
2311                  * sport and dport as well which makes it not worthwhile to
2312                  * look for them.
2313                  * Thus, when ackskew is negative but still seems to belong
2314                  * to this session, we bump up the destinations end value.
2315                  */
2316                 if (ackskew < 0)
2317                         tdata->td_end = ack;
2318
2319                 /* update max window seen */
2320                 if (fdata->td_maxwin < win)
2321                         fdata->td_maxwin = win;
2322                 if (SEQ_GT(end, fdata->td_end))
2323                         fdata->td_end = end;
2324                 if (SEQ_GE(ack + win, tdata->td_maxend))
2325                         tdata->td_maxend = ack + win;
2326                 return 1;
2327         }
2328         SBUMP(ipf_state_stats.iss_oow);
2329         fin->fin_flx |= FI_OOW;
2330         return 0;
2331 }
2332
2333
2334 /* ------------------------------------------------------------------------ */
2335 /* Function:    ipf_state_clone                                             */
2336 /* Returns:     ipstate_t* - NULL == cloning failed,                        */
2337 /*                           else pointer to new state structure            */
2338 /* Parameters:  fin(I) - pointer to packet information                      */
2339 /*              tcp(I) - pointer to TCP/UDP header                          */
2340 /*              is(I)  - pointer to master state structure                  */
2341 /*                                                                          */
2342 /* Create a "duplcate" state table entry from the master.                   */
2343 /* ------------------------------------------------------------------------ */
2344 static ipstate_t *
2345 ipf_state_clone(fin, tcp, is)
2346         fr_info_t *fin;
2347         tcphdr_t *tcp;
2348         ipstate_t *is;
2349 {
2350         ipf_main_softc_t *softc = fin->fin_main_soft;
2351         ipf_state_softc_t *softs = softc->ipf_state_soft;
2352         ipstate_t *clone;
2353         u_32_t send;
2354
2355         if (softs->ipf_state_stats.iss_active == softs->ipf_state_max) {
2356                 SBUMPD(ipf_state_stats, iss_max);
2357                 softs->ipf_state_doflush = 1;
2358                 return NULL;
2359         }
2360         KMALLOC(clone, ipstate_t *);
2361         if (clone == NULL) {
2362                 SBUMPD(ipf_state_stats, iss_clone_nomem);
2363                 return NULL;
2364         }
2365         bcopy((char *)is, (char *)clone, sizeof(*clone));
2366
2367         MUTEX_NUKE(&clone->is_lock);
2368         /*
2369          * It has not yet been placed on any timeout queue, so make sure
2370          * all of that data is zero'd out.
2371          */
2372         clone->is_sti.tqe_pnext = NULL;
2373         clone->is_sti.tqe_next = NULL;
2374         clone->is_sti.tqe_ifq = NULL;
2375         clone->is_sti.tqe_parent = clone;
2376
2377         clone->is_die = ONE_DAY + softc->ipf_ticks;
2378         clone->is_state[0] = 0;
2379         clone->is_state[1] = 0;
2380         send = ntohl(tcp->th_seq) + fin->fin_dlen - (TCP_OFF(tcp) << 2) +
2381                 ((tcp->th_flags & TH_SYN) ? 1 : 0) +
2382                 ((tcp->th_flags & TH_FIN) ? 1 : 0);
2383
2384         if (fin->fin_rev == 1) {
2385                 clone->is_dend = send;
2386                 clone->is_maxdend = send;
2387                 clone->is_send = 0;
2388                 clone->is_maxswin = 1;
2389                 clone->is_maxdwin = ntohs(tcp->th_win);
2390                 if (clone->is_maxdwin == 0)
2391                         clone->is_maxdwin = 1;
2392         } else {
2393                 clone->is_send = send;
2394                 clone->is_maxsend = send;
2395                 clone->is_dend = 0;
2396                 clone->is_maxdwin = 1;
2397                 clone->is_maxswin = ntohs(tcp->th_win);
2398                 if (clone->is_maxswin == 0)
2399                         clone->is_maxswin = 1;
2400         }
2401
2402         clone->is_flags &= ~SI_CLONE;
2403         clone->is_flags |= SI_CLONED;
2404         if (ipf_state_insert(softc, clone, fin->fin_rev) == -1) {
2405                 KFREE(clone);
2406                 return NULL;
2407         }
2408
2409         clone->is_ref = 1;
2410         if (clone->is_p == IPPROTO_TCP) {
2411                 (void) ipf_tcp_age(&clone->is_sti, fin, softs->ipf_state_tcptq,
2412                                    clone->is_flags, 2);
2413         }
2414         MUTEX_EXIT(&clone->is_lock);
2415         if (is->is_flags & IS_STATESYNC)
2416                 clone->is_sync = ipf_sync_new(softc, SMC_STATE, fin, clone);
2417         DT2(iss_clone, ipstate_t *, is, ipstate_t *, clone);
2418         SBUMP(ipf_state_stats.iss_cloned);
2419         return clone;
2420 }
2421
2422
2423 /* ------------------------------------------------------------------------ */
2424 /* Function:    ipf_matchsrcdst                                             */
2425 /* Returns:     Nil                                                         */
2426 /* Parameters:  fin(I)   - pointer to packet information                    */
2427 /*              is(I)    - pointer to state structure                       */
2428 /*              src(I)   - pointer to source address                        */
2429 /*              dst(I)   - pointer to destination address                   */
2430 /*              tcp(I)   - pointer to TCP/UDP header                        */
2431 /*              cmask(I) - mask of FI_* bits to check                       */
2432 /*                                                                          */
2433 /* Match a state table entry against an IP packet.  The logic below is that */
2434 /* ret gets set to one if the match succeeds, else remains 0.  If it is     */
2435 /* still 0 after the test. no match.                                        */
2436 /* ------------------------------------------------------------------------ */
2437 static ipstate_t *
2438 ipf_matchsrcdst(fin, is, src, dst, tcp, cmask)
2439         fr_info_t *fin;
2440         ipstate_t *is;
2441         i6addr_t *src, *dst;
2442         tcphdr_t *tcp;
2443         u_32_t cmask;
2444 {
2445         ipf_main_softc_t *softc = fin->fin_main_soft;
2446         ipf_state_softc_t *softs = softc->ipf_state_soft;
2447         int ret = 0, rev, out, flags, flx = 0, idx;
2448         u_short sp, dp;
2449         u_32_t cflx;
2450         void *ifp;
2451
2452         /*
2453          * If a connection is about to be deleted, no packets
2454          * are allowed to match it.
2455          */
2456         if (is->is_sti.tqe_ifq == &softs->ipf_state_deletetq)
2457                 return NULL;
2458
2459         rev = IP6_NEQ(&is->is_dst, dst);
2460         ifp = fin->fin_ifp;
2461         out = fin->fin_out;
2462         flags = is->is_flags;
2463         sp = 0;
2464         dp = 0;
2465
2466         if (tcp != NULL) {
2467                 sp = htons(fin->fin_sport);
2468                 dp = ntohs(fin->fin_dport);
2469         }
2470         if (!rev) {
2471                 if (tcp != NULL) {
2472                         if (!(flags & SI_W_SPORT) && (sp != is->is_sport))
2473                                 rev = 1;
2474                         else if (!(flags & SI_W_DPORT) && (dp != is->is_dport))
2475                                 rev = 1;
2476                 }
2477         }
2478
2479         idx = (out << 1) + rev;
2480
2481         /*
2482          * If the interface for this 'direction' is set, make sure it matches.
2483          * An interface name that is not set matches any, as does a name of *.
2484          */
2485         if ((is->is_ifp[idx] == ifp) || (is->is_ifp[idx] == NULL &&
2486             (*is->is_ifname[idx] == '\0' || *is->is_ifname[idx] == '-' ||
2487              *is->is_ifname[idx] == '*')))
2488                 ret = 1;
2489
2490         if (ret == 0) {
2491                 DT2(iss_lookup_badifp, fr_info_t *, fin, ipstate_t *, is);
2492                 SBUMP(ipf_state_stats.iss_lookup_badifp);
2493                 /* TRACE is, out, rev, idx */
2494                 return NULL;
2495         }
2496         ret = 0;
2497
2498         /*
2499          * Match addresses and ports.
2500          */
2501         if (rev == 0) {
2502                 if ((IP6_EQ(&is->is_dst, dst) || (flags & SI_W_DADDR)) &&
2503                     (IP6_EQ(&is->is_src, src) || (flags & SI_W_SADDR))) {
2504                         if (tcp) {
2505                                 if ((sp == is->is_sport || flags & SI_W_SPORT)
2506                                     &&
2507                                     (dp == is->is_dport || flags & SI_W_DPORT))
2508                                         ret = 1;
2509                         } else {
2510                                 ret = 1;
2511                         }
2512                 }
2513         } else {
2514                 if ((IP6_EQ(&is->is_dst, src) || (flags & SI_W_DADDR)) &&
2515                     (IP6_EQ(&is->is_src, dst) || (flags & SI_W_SADDR))) {
2516                         if (tcp) {
2517                                 if ((dp == is->is_sport || flags & SI_W_SPORT)
2518                                     &&
2519                                     (sp == is->is_dport || flags & SI_W_DPORT))
2520                                         ret = 1;
2521                         } else {
2522                                 ret = 1;
2523                         }
2524                 }
2525         }
2526
2527         if (ret == 0) {
2528                 SBUMP(ipf_state_stats.iss_lookup_badport);
2529                 DT2(iss_lookup_badport, fr_info_t *, fin, ipstate_t *, is);
2530                 /* TRACE rev, is, sp, dp, src, dst */
2531                 return NULL;
2532         }
2533
2534         /*
2535          * Whether or not this should be here, is questionable, but the aim
2536          * is to get this out of the main line.
2537          */
2538         if (tcp == NULL)
2539                 flags = is->is_flags & ~(SI_WILDP|SI_NEWFR|SI_CLONE|SI_CLONED);
2540
2541         /*
2542          * Only one of the source or destination address can be flaged as a
2543          * wildcard.  Fill in the missing address, if set.
2544          * For IPv6, if the address being copied in is multicast, then
2545          * don't reset the wild flag - multicast causes it to be set in the
2546          * first place!
2547          */
2548         if ((flags & (SI_W_SADDR|SI_W_DADDR))) {
2549                 fr_ip_t *fi = &fin->fin_fi;
2550
2551                 if ((flags & SI_W_SADDR) != 0) {
2552                         if (rev == 0) {
2553                                 is->is_src = fi->fi_src;
2554                                 is->is_flags &= ~SI_W_SADDR;
2555                         } else {
2556                                 if (!(fin->fin_flx & (FI_MULTICAST|FI_MBCAST))){
2557                                         is->is_src = fi->fi_dst;
2558                                         is->is_flags &= ~SI_W_SADDR;
2559                                 }
2560                         }
2561                 } else if ((flags & SI_W_DADDR) != 0) {
2562                         if (rev == 0) {
2563                                 if (!(fin->fin_flx & (FI_MULTICAST|FI_MBCAST))){
2564                                         is->is_dst = fi->fi_dst;
2565                                         is->is_flags &= ~SI_W_DADDR;
2566                                 }
2567                         } else {
2568                                 is->is_dst = fi->fi_src;
2569                                 is->is_flags &= ~SI_W_DADDR;
2570                         }
2571                 }
2572                 if ((is->is_flags & (SI_WILDA|SI_WILDP)) == 0) {
2573                         ATOMIC_DECL(softs->ipf_state_stats.iss_wild);
2574                 }
2575         }
2576
2577         flx = fin->fin_flx & cmask;
2578         cflx = is->is_flx[out][rev];
2579
2580         /*
2581          * Match up any flags set from IP options.
2582          */
2583         if ((cflx && (flx != (cflx & cmask))) ||
2584             ((fin->fin_optmsk & is->is_optmsk[rev]) != is->is_opt[rev]) ||
2585             ((fin->fin_secmsk & is->is_secmsk) != is->is_sec) ||
2586             ((fin->fin_auth & is->is_authmsk) != is->is_auth)) {
2587                 SBUMPD(ipf_state_stats, iss_miss_mask);
2588                 return NULL;
2589         }
2590
2591         if ((fin->fin_flx & FI_IGNORE) != 0) {
2592                 fin->fin_rev = rev;
2593                 return is;
2594         }
2595
2596         /*
2597          * Only one of the source or destination port can be flagged as a
2598          * wildcard.  When filling it in, fill in a copy of the matched entry
2599          * if it has the cloning flag set.
2600          */
2601         if ((flags & (SI_W_SPORT|SI_W_DPORT))) {
2602                 if ((flags & SI_CLONE) != 0) {
2603                         ipstate_t *clone;
2604
2605                         clone = ipf_state_clone(fin, tcp, is);
2606                         if (clone == NULL)
2607                                 return NULL;
2608                         is = clone;
2609                 } else {
2610                         ATOMIC_DECL(softs->ipf_state_stats.iss_wild);
2611                 }
2612
2613                 if ((flags & SI_W_SPORT) != 0) {
2614                         if (rev == 0) {
2615                                 is->is_sport = sp;
2616                                 is->is_send = ntohl(tcp->th_seq);
2617                         } else {
2618                                 is->is_sport = dp;
2619                                 is->is_send = ntohl(tcp->th_ack);
2620                         }
2621                         is->is_maxsend = is->is_send + 1;
2622                 } else if ((flags & SI_W_DPORT) != 0) {
2623                         if (rev == 0) {
2624                                 is->is_dport = dp;
2625                                 is->is_dend = ntohl(tcp->th_ack);
2626                         } else {
2627                                 is->is_dport = sp;
2628                                 is->is_dend = ntohl(tcp->th_seq);
2629                         }
2630                         is->is_maxdend = is->is_dend + 1;
2631                 }
2632                 is->is_flags &= ~(SI_W_SPORT|SI_W_DPORT);
2633                 if ((flags & SI_CLONED) && softs->ipf_state_logging)
2634                         ipf_state_log(softc, is, ISL_CLONE);
2635         }
2636
2637         ret = -1;
2638
2639         if (is->is_flx[out][rev] == 0) {
2640                 is->is_flx[out][rev] = flx;
2641                 if (rev == 1 && is->is_optmsk[1] == 0) {
2642                         is->is_opt[1] = fin->fin_optmsk;
2643                         is->is_optmsk[1] = 0xffffffff;
2644                         if (is->is_v == 6) {
2645                                 is->is_opt[1] &= ~0x8;
2646                                 is->is_optmsk[1] &= ~0x8;
2647                         }
2648                 }
2649         }
2650
2651         /*
2652          * Check if the interface name for this "direction" is set and if not,
2653          * fill it in.
2654          */
2655         if (is->is_ifp[idx] == NULL &&
2656             (*is->is_ifname[idx] == '\0' || *is->is_ifname[idx] == '*')) {
2657                 is->is_ifp[idx] = ifp;
2658                 COPYIFNAME(fin->fin_v, ifp, is->is_ifname[idx]);
2659         }
2660         fin->fin_rev = rev;
2661         return is;
2662 }
2663
2664
2665 /* ------------------------------------------------------------------------ */
2666 /* Function:    ipf_checkicmpmatchingstate                                  */
2667 /* Returns:     Nil                                                         */
2668 /* Parameters:  fin(I) - pointer to packet information                      */
2669 /*                                                                          */
2670 /* If we've got an ICMP error message, using the information stored in the  */
2671 /* ICMP packet, look for a matching state table entry.                      */
2672 /*                                                                          */
2673 /* If we return NULL then no lock on ipf_state is held.                     */
2674 /* If we return non-null then a read-lock on ipf_state is held.             */
2675 /* ------------------------------------------------------------------------ */
2676 static ipstate_t *
2677 ipf_checkicmpmatchingstate(fin)
2678         fr_info_t *fin;
2679 {
2680         ipf_main_softc_t *softc = fin->fin_main_soft;
2681         ipf_state_softc_t *softs = softc->ipf_state_soft;
2682         ipstate_t *is, **isp;
2683         i6addr_t dst, src;
2684         struct icmp *ic;
2685         u_short savelen;
2686         icmphdr_t *icmp;
2687         fr_info_t ofin;
2688         tcphdr_t *tcp;
2689         int type, len;
2690         u_char  pr;
2691         ip_t *oip;
2692         u_int hv;
2693
2694         /*
2695          * Does it at least have the return (basic) IP header ?
2696          * Is it an actual recognised ICMP error type?
2697          * Only a basic IP header (no options) should be with
2698          * an ICMP error header.
2699          */
2700         if ((fin->fin_v != 4) || (fin->fin_hlen != sizeof(ip_t)) ||
2701             (fin->fin_plen < ICMPERR_MINPKTLEN) ||
2702             !(fin->fin_flx & FI_ICMPERR)) {
2703                 SBUMPD(ipf_state_stats, iss_icmp_bad);
2704                 return NULL;
2705         }
2706         ic = fin->fin_dp;
2707         type = ic->icmp_type;
2708
2709         oip = (ip_t *)((char *)ic + ICMPERR_ICMPHLEN);
2710         /*
2711          * Check if the at least the old IP header (with options) and
2712          * 8 bytes of payload is present.
2713          */
2714         if (fin->fin_plen < ICMPERR_MAXPKTLEN + ((IP_HL(oip) - 5) << 2)) {
2715                 SBUMPDX(ipf_state_stats, iss_icmp_short, iss_icmp_short_1);
2716                 return NULL;
2717         }
2718
2719         /*
2720          * Sanity Checks.
2721          */
2722         len = fin->fin_dlen - ICMPERR_ICMPHLEN;
2723         if ((len <= 0) || ((IP_HL(oip) << 2) > len)) {
2724                 DT2(iss_icmp_len, fr_info_t *, fin, struct ip*, oip);
2725                 SBUMPDX(ipf_state_stats, iss_icmp_short, iss_icmp_short_1);
2726                 return NULL;
2727         }
2728
2729         /*
2730          * Is the buffer big enough for all of it ?  It's the size of the IP
2731          * header claimed in the encapsulated part which is of concern.  It
2732          * may be too big to be in this buffer but not so big that it's
2733          * outside the ICMP packet, leading to TCP deref's causing problems.
2734          * This is possible because we don't know how big oip_hl is when we
2735          * do the pullup early in ipf_check() and thus can't guarantee it is
2736          * all here now.
2737          */
2738 #ifdef  _KERNEL
2739         {
2740         mb_t *m;
2741
2742         m = fin->fin_m;
2743 # if defined(MENTAT)
2744         if ((char *)oip + len > (char *)m->b_wptr) {
2745                 SBUMPDX(ipf_state_stats, iss_icmp_short, iss_icmp_short_2);
2746                 return NULL;
2747         }
2748 # else
2749         if ((char *)oip + len > (char *)fin->fin_ip + m->m_len) {
2750                 SBUMPDX(ipf_state_stats, iss_icmp_short, iss_icmp_short_3);
2751                 return NULL;
2752         }
2753 # endif
2754         }
2755 #endif
2756
2757         bcopy((char *)fin, (char *)&ofin, sizeof(*fin));
2758
2759         /*
2760          * in the IPv4 case we must zero the i6addr union otherwise
2761          * the IP6_EQ and IP6_NEQ macros produce the wrong results because
2762          * of the 'junk' in the unused part of the union
2763          */
2764         bzero((char *)&src, sizeof(src));
2765         bzero((char *)&dst, sizeof(dst));
2766
2767         /*
2768          * we make an fin entry to be able to feed it to
2769          * matchsrcdst note that not all fields are encessary
2770          * but this is the cleanest way. Note further we fill
2771          * in fin_mp such that if someone uses it we'll get
2772          * a kernel panic. ipf_matchsrcdst does not use this.
2773          *
2774          * watch out here, as ip is in host order and oip in network
2775          * order. Any change we make must be undone afterwards, like
2776          * oip->ip_len.
2777          */
2778         savelen = oip->ip_len;
2779         oip->ip_len = htons(len);
2780
2781         ofin.fin_flx = FI_NOCKSUM;
2782         ofin.fin_v = 4;
2783         ofin.fin_ip = oip;
2784         ofin.fin_m = NULL;      /* if dereferenced, panic XXX */
2785         ofin.fin_mp = NULL;     /* if dereferenced, panic XXX */
2786         (void) ipf_makefrip(IP_HL(oip) << 2, oip, &ofin);
2787         ofin.fin_ifp = fin->fin_ifp;
2788         ofin.fin_out = !fin->fin_out;
2789
2790         hv = (pr = oip->ip_p);
2791         src.in4 = oip->ip_src;
2792         hv += src.in4.s_addr;
2793         dst.in4 = oip->ip_dst;
2794         hv += dst.in4.s_addr;
2795
2796         /*
2797          * Reset the short and bad flag here because in ipf_matchsrcdst()
2798          * the flags for the current packet (fin_flx) are compared against
2799          * those for the existing session.
2800          */
2801         ofin.fin_flx &= ~(FI_BAD|FI_SHORT);
2802
2803         /*
2804          * Put old values of ip_len back as we don't know
2805          * if we have to forward the packet or process it again.
2806          */
2807         oip->ip_len = savelen;
2808
2809         switch (oip->ip_p)
2810         {
2811         case IPPROTO_ICMP :
2812                 /*
2813                  * an ICMP error can only be generated as a result of an
2814                  * ICMP query, not as the response on an ICMP error
2815                  *
2816                  * XXX theoretically ICMP_ECHOREP and the other reply's are
2817                  * ICMP query's as well, but adding them here seems strange XXX
2818                  */
2819                 if ((ofin.fin_flx & FI_ICMPERR) != 0) {
2820                         DT1(iss_icmp_icmperr, fr_info_t *, &ofin);
2821                         SBUMP(ipf_state_stats.iss_icmp_icmperr);
2822                         return NULL;
2823                 }
2824
2825                 /*
2826                  * perform a lookup of the ICMP packet in the state table
2827                  */
2828                 icmp = (icmphdr_t *)((char *)oip + (IP_HL(oip) << 2));
2829                 hv += icmp->icmp_id;
2830                 hv = DOUBLE_HASH(hv);
2831
2832                 READ_ENTER(&softc->ipf_state);
2833                 for (isp = &softs->ipf_state_table[hv];
2834                      ((is = *isp) != NULL); ) {
2835                         isp = &is->is_hnext;
2836                         if ((is->is_p != pr) || (is->is_v != 4))
2837                                 continue;
2838                         if (is->is_pass & FR_NOICMPERR)
2839                                 continue;
2840
2841                         is = ipf_matchsrcdst(&ofin, is, &src, &dst,
2842                                             NULL, FI_ICMPCMP);
2843                         if ((is != NULL) && !ipf_allowstateicmp(fin, is, &src))
2844                                 return is;
2845                 }
2846                 RWLOCK_EXIT(&softc->ipf_state);
2847                 SBUMPDX(ipf_state_stats, iss_icmp_miss, iss_icmp_miss_1);
2848                 return NULL;
2849         case IPPROTO_TCP :
2850         case IPPROTO_UDP :
2851                 break;
2852         default :
2853                 SBUMPDX(ipf_state_stats, iss_icmp_miss, iss_icmp_miss_2);
2854                 return NULL;
2855         }
2856
2857         tcp = (tcphdr_t *)((char *)oip + (IP_HL(oip) << 2));
2858
2859         hv += tcp->th_dport;;
2860         hv += tcp->th_sport;;
2861         hv = DOUBLE_HASH(hv);
2862
2863         READ_ENTER(&softc->ipf_state);
2864         for (isp = &softs->ipf_state_table[hv]; ((is = *isp) != NULL); ) {
2865                 isp = &is->is_hnext;
2866                 /*
2867                  * Only allow this icmp though if the
2868                  * encapsulated packet was allowed through the
2869                  * other way around. Note that the minimal amount
2870                  * of info present does not allow for checking against
2871                  * tcp internals such as seq and ack numbers.   Only the
2872                  * ports are known to be present and can be even if the
2873                  * short flag is set.
2874                  */
2875                 if ((is->is_p == pr) && (is->is_v == 4) &&
2876                     (is = ipf_matchsrcdst(&ofin, is, &src, &dst,
2877                                           tcp, FI_ICMPCMP))) {
2878                         if (ipf_allowstateicmp(fin, is, &src) == 0)
2879                                 return is;
2880                 }
2881         }
2882         RWLOCK_EXIT(&softc->ipf_state);
2883         SBUMPDX(ipf_state_stats, iss_icmp_miss, iss_icmp_miss_3);
2884         return NULL;
2885 }
2886
2887
2888 /* ------------------------------------------------------------------------ */
2889 /* Function:    ipf_allowstateicmp                                          */
2890 /* Returns:     int - 1 = packet denied, 0 = packet allowed                 */
2891 /* Parameters:  fin(I) - pointer to packet information                      */
2892 /*              is(I)  - pointer to state table entry                       */
2893 /*              src(I) - source address to check permission for             */
2894 /*                                                                          */
2895 /* For an ICMP packet that has so far matched a state table entry, check if */
2896 /* there are any further refinements that might mean we want to block this  */
2897 /* packet.  This code isn't specific to either IPv4 or IPv6.                */
2898 /* ------------------------------------------------------------------------ */
2899 static int
2900 ipf_allowstateicmp(fin, is, src)
2901         fr_info_t *fin;
2902         ipstate_t *is;
2903         i6addr_t *src;
2904 {
2905         ipf_main_softc_t *softc = fin->fin_main_soft;
2906         ipf_state_softc_t *softs = softc->ipf_state_soft;
2907         frentry_t *savefr;
2908         frentry_t *fr;
2909         u_32_t ipass;
2910         int backward;
2911         int oi;
2912         int i;
2913
2914         fr = is->is_rule;
2915         if (fr != NULL && fr->fr_icmpgrp != NULL) {
2916                 savefr = fin->fin_fr;
2917                 fin->fin_fr = fr->fr_icmpgrp->fg_start;
2918
2919                 ipass = ipf_scanlist(fin, softc->ipf_pass);
2920                 fin->fin_fr = savefr;
2921                 if (FR_ISBLOCK(ipass)) {
2922                         SBUMPD(ipf_state_stats, iss_icmp_headblock);
2923                         return 1;
2924                 }
2925         }
2926
2927         /*
2928          * i  : the index of this packet (the icmp unreachable)
2929          * oi : the index of the original packet found in the
2930          *      icmp header (i.e. the packet causing this icmp)
2931          * backward : original packet was backward compared to
2932          *            the state
2933          */
2934         backward = IP6_NEQ(&is->is_src, src);
2935         fin->fin_rev = !backward;
2936         i = (!backward << 1) + fin->fin_out;
2937         oi = (backward << 1) + !fin->fin_out;
2938
2939         if (is->is_pass & FR_NOICMPERR) {
2940                 SBUMPD(ipf_state_stats, iss_icmp_banned);
2941                 return 1;
2942         }
2943         if (is->is_icmppkts[i] > is->is_pkts[oi]) {
2944                 SBUMPD(ipf_state_stats, iss_icmp_toomany);
2945                 return 1;
2946         }
2947
2948         DT2(iss_icmp_hits, fr_info_t *, fin, ipstate_t *, is);
2949         SBUMP(ipf_state_stats.iss_icmp_hits);
2950         is->is_icmppkts[i]++;
2951
2952         /*
2953          * we deliberately do not touch the timeouts
2954          * for the accompanying state table entry.
2955          * It remains to be seen if that is correct. XXX
2956          */
2957         return 0;
2958 }
2959
2960
2961 /* ------------------------------------------------------------------------ */
2962 /* Function:    ipf_ipsmove                                                 */
2963 /* Returns:     Nil                                                         */
2964 /* Parameters:  is(I) - pointer to state table entry                        */
2965 /*              hv(I) - new hash value for state table entry                */
2966 /* Write Locks: ipf_state                                                   */
2967 /*                                                                          */
2968 /* Move a state entry from one position in the hash table to another.       */
2969 /* ------------------------------------------------------------------------ */
2970 static void
2971 ipf_ipsmove(softs, is, hv)
2972         ipf_state_softc_t *softs;
2973         ipstate_t *is;
2974         u_int hv;
2975 {
2976         ipstate_t **isp;
2977         u_int hvm;
2978
2979         hvm = is->is_hv;
2980
2981         /* TRACE is, is_hv, hvm */
2982
2983         /*
2984          * Remove the hash from the old location...
2985          */
2986         isp = is->is_phnext;
2987         if (is->is_hnext)
2988                 is->is_hnext->is_phnext = isp;
2989         *isp = is->is_hnext;
2990         if (softs->ipf_state_table[hvm] == NULL)
2991                 softs->ipf_state_stats.iss_inuse--;
2992         softs->ipf_state_stats.iss_bucketlen[hvm]--;
2993
2994         /*
2995          * ...and put the hash in the new one.
2996          */
2997         hvm = DOUBLE_HASH(hv);
2998         is->is_hv = hvm;
2999
3000         /* TRACE is, hv, is_hv, hvm */
3001
3002         isp = &softs->ipf_state_table[hvm];
3003         if (*isp)
3004                 (*isp)->is_phnext = &is->is_hnext;
3005         else
3006                 softs->ipf_state_stats.iss_inuse++;
3007         softs->ipf_state_stats.iss_bucketlen[hvm]++;
3008         is->is_phnext = isp;
3009         is->is_hnext = *isp;
3010         *isp = is;
3011 }
3012
3013
3014 /* ------------------------------------------------------------------------ */
3015 /* Function:    ipf_state_lookup                                            */
3016 /* Returns:     ipstate_t* - NULL == no matching state found,               */
3017 /*                           else pointer to state information is returned  */
3018 /* Parameters:  fin(I)  - pointer to packet information                     */
3019 /*              tcp(I)  - pointer to TCP/UDP header.                        */
3020 /*              ifqp(O) - pointer for storing tailq timeout                 */
3021 /*                                                                          */
3022 /* Search the state table for a matching entry to the packet described by   */
3023 /* the contents of *fin. For certain protocols, when a match is found the   */
3024 /* timeout queue is also selected and stored in ifpq if it is non-NULL.     */
3025 /*                                                                          */
3026 /* If we return NULL then no lock on ipf_state is held.                     */
3027 /* If we return non-null then a read-lock on ipf_state is held.             */
3028 /* ------------------------------------------------------------------------ */
3029 ipstate_t *
3030 ipf_state_lookup(fin, tcp, ifqp)
3031         fr_info_t *fin;
3032         tcphdr_t *tcp;
3033         ipftq_t **ifqp;
3034 {
3035         ipf_main_softc_t *softc = fin->fin_main_soft;
3036         ipf_state_softc_t *softs = softc->ipf_state_soft;
3037         u_int hv, hvm, pr, v, tryagain;
3038         ipstate_t *is, **isp;
3039         u_short dport, sport;
3040         i6addr_t src, dst;
3041         struct icmp *ic;
3042         ipftq_t *ifq;
3043         int oow;
3044
3045         is = NULL;
3046         ifq = NULL;
3047         tcp = fin->fin_dp;
3048         ic = (struct icmp *)tcp;
3049         hv = (pr = fin->fin_fi.fi_p);
3050         src = fin->fin_fi.fi_src;
3051         dst = fin->fin_fi.fi_dst;
3052         hv += src.in4.s_addr;
3053         hv += dst.in4.s_addr;
3054
3055         v = fin->fin_fi.fi_v;
3056 #ifdef  USE_INET6
3057         if (v == 6) {
3058                 hv  += fin->fin_fi.fi_src.i6[1];
3059                 hv  += fin->fin_fi.fi_src.i6[2];
3060                 hv  += fin->fin_fi.fi_src.i6[3];
3061
3062                 if ((fin->fin_p == IPPROTO_ICMPV6) &&
3063                     IN6_IS_ADDR_MULTICAST(&fin->fin_fi.fi_dst.in6)) {
3064                         hv -= dst.in4.s_addr;
3065                 } else {
3066                         hv += fin->fin_fi.fi_dst.i6[1];
3067                         hv += fin->fin_fi.fi_dst.i6[2];
3068                         hv += fin->fin_fi.fi_dst.i6[3];
3069                 }
3070         }
3071 #endif
3072         if ((v == 4) &&
3073             (fin->fin_flx & (FI_MULTICAST|FI_BROADCAST|FI_MBCAST))) {
3074                 if (fin->fin_out == 0) {
3075                         hv -= src.in4.s_addr;
3076                 } else {
3077                         hv -= dst.in4.s_addr;
3078                 }
3079         }
3080
3081         /* TRACE fin_saddr, fin_daddr, hv */
3082
3083         /*
3084          * Search the hash table for matching packet header info.
3085          */
3086         switch (pr)
3087         {
3088 #ifdef  USE_INET6
3089         case IPPROTO_ICMPV6 :
3090                 tryagain = 0;
3091                 if (v == 6) {
3092                         if ((ic->icmp_type == ICMP6_ECHO_REQUEST) ||
3093                             (ic->icmp_type == ICMP6_ECHO_REPLY)) {
3094                                 hv += ic->icmp_id;
3095                         }
3096                 }
3097                 READ_ENTER(&softc->ipf_state);
3098 icmp6again:
3099                 hvm = DOUBLE_HASH(hv);
3100                 for (isp = &softs->ipf_state_table[hvm];
3101                      ((is = *isp) != NULL); ) {
3102                         isp = &is->is_hnext;
3103                         if ((is->is_p != pr) || (is->is_v != v))
3104                                 continue;
3105                         is = ipf_matchsrcdst(fin, is, &src, &dst, NULL, FI_CMP);
3106                         if (is != NULL &&
3107                             ipf_matchicmpqueryreply(v, &is->is_icmp,
3108                                                    ic, fin->fin_rev)) {
3109                                 if (fin->fin_rev)
3110                                         ifq = &softs->ipf_state_icmpacktq;
3111                                 else
3112                                         ifq = &softs->ipf_state_icmptq;
3113                                 break;
3114                         }
3115                 }
3116
3117                 if (is != NULL) {
3118                         if ((tryagain != 0) && !(is->is_flags & SI_W_DADDR)) {
3119                                 hv += fin->fin_fi.fi_src.i6[0];
3120                                 hv += fin->fin_fi.fi_src.i6[1];
3121                                 hv += fin->fin_fi.fi_src.i6[2];
3122                                 hv += fin->fin_fi.fi_src.i6[3];
3123                                 ipf_ipsmove(softs, is, hv);
3124                                 MUTEX_DOWNGRADE(&softc->ipf_state);
3125                         }
3126                         break;
3127                 }
3128                 RWLOCK_EXIT(&softc->ipf_state);
3129
3130                 /*
3131                  * No matching icmp state entry. Perhaps this is a
3132                  * response to another state entry.
3133                  *
3134                  * XXX With some ICMP6 packets, the "other" address is already
3135                  * in the packet, after the ICMP6 header, and this could be
3136                  * used in place of the multicast address.  However, taking
3137                  * advantage of this requires some significant code changes
3138                  * to handle the specific types where that is the case.
3139                  */
3140                 if ((softs->ipf_state_stats.iss_wild != 0) &&
3141                     ((fin->fin_flx & FI_NOWILD) == 0) &&
3142                     (v == 6) && (tryagain == 0)) {
3143                         hv -= fin->fin_fi.fi_src.i6[0];
3144                         hv -= fin->fin_fi.fi_src.i6[1];
3145                         hv -= fin->fin_fi.fi_src.i6[2];
3146                         hv -= fin->fin_fi.fi_src.i6[3];
3147                         tryagain = 1;
3148                         WRITE_ENTER(&softc->ipf_state);
3149                         goto icmp6again;
3150                 }
3151
3152                 is = ipf_checkicmp6matchingstate(fin);
3153                 if (is != NULL)
3154                         return is;
3155                 break;
3156 #endif
3157
3158         case IPPROTO_ICMP :
3159                 if (v == 4) {
3160                         hv += ic->icmp_id;
3161                 }
3162                 hv = DOUBLE_HASH(hv);
3163                 READ_ENTER(&softc->ipf_state);
3164                 for (isp = &softs->ipf_state_table[hv];
3165                      ((is = *isp) != NULL); ) {
3166                         isp = &is->is_hnext;
3167                         if ((is->is_p != pr) || (is->is_v != v))
3168                                 continue;
3169                         is = ipf_matchsrcdst(fin, is, &src, &dst, NULL, FI_CMP);
3170                         if ((is != NULL) &&
3171                             (ic->icmp_id == is->is_icmp.ici_id) &&
3172                             ipf_matchicmpqueryreply(v, &is->is_icmp,
3173                                                    ic, fin->fin_rev)) {
3174                                 if (fin->fin_rev)
3175                                         ifq = &softs->ipf_state_icmpacktq;
3176                                 else
3177                                         ifq = &softs->ipf_state_icmptq;
3178                                 break;
3179                         }
3180                 }
3181                 if (is == NULL) {
3182                         RWLOCK_EXIT(&softc->ipf_state);
3183                 }
3184                 break;
3185
3186         case IPPROTO_TCP :
3187         case IPPROTO_UDP :
3188                 ifqp = NULL;
3189                 sport = htons(fin->fin_data[0]);
3190                 hv += sport;
3191                 dport = htons(fin->fin_data[1]);
3192                 hv += dport;
3193                 oow = 0;
3194                 tryagain = 0;
3195                 READ_ENTER(&softc->ipf_state);
3196 retry_tcpudp:
3197                 hvm = DOUBLE_HASH(hv);
3198
3199                 /* TRACE hv, hvm */
3200
3201                 for (isp = &softs->ipf_state_table[hvm];
3202                      ((is = *isp) != NULL); ) {
3203                         isp = &is->is_hnext;
3204                         if ((is->is_p != pr) || (is->is_v != v))
3205                                 continue;
3206                         fin->fin_flx &= ~FI_OOW;
3207                         is = ipf_matchsrcdst(fin, is, &src, &dst, tcp, FI_CMP);
3208                         if (is != NULL) {
3209                                 if (pr == IPPROTO_TCP) {
3210                                         if (!ipf_state_tcp(softc, softs, fin,
3211                                                            tcp, is)) {
3212                                                 oow |= fin->fin_flx & FI_OOW;
3213                                                 continue;
3214                                         }
3215                                 }
3216                                 break;
3217                         }
3218                 }
3219                 if (is != NULL) {
3220                         if (tryagain &&
3221                             !(is->is_flags & (SI_CLONE|SI_WILDP|SI_WILDA))) {
3222                                 hv += dport;
3223                                 hv += sport;
3224                                 ipf_ipsmove(softs, is, hv);
3225                                 MUTEX_DOWNGRADE(&softc->ipf_state);
3226                         }
3227                         break;
3228                 }
3229                 RWLOCK_EXIT(&softc->ipf_state);
3230
3231                 if ((softs->ipf_state_stats.iss_wild != 0) &&
3232                     ((fin->fin_flx & FI_NOWILD) == 0)) {
3233                         if (tryagain == 0) {
3234                                 hv -= dport;
3235                                 hv -= sport;
3236                         } else if (tryagain == 1) {
3237                                 hv = fin->fin_fi.fi_p;
3238                                 /*
3239                                  * If we try to pretend this is a reply to a
3240                                  * multicast/broadcast packet then we need to
3241                                  * exclude part of the address from the hash
3242                                  * calculation.
3243                                  */
3244                                 if (fin->fin_out == 0) {
3245                                         hv += src.in4.s_addr;
3246                                 } else {
3247                                         hv += dst.in4.s_addr;
3248                                 }
3249                                 hv += dport;
3250                                 hv += sport;
3251                         }
3252                         tryagain++;
3253                         if (tryagain <= 2) {
3254                                 WRITE_ENTER(&softc->ipf_state);
3255                                 goto retry_tcpudp;
3256                         }
3257                 }
3258                 fin->fin_flx |= oow;
3259                 break;
3260
3261 #if 0
3262         case IPPROTO_GRE :
3263                 gre = fin->fin_dp;
3264                 if (GRE_REV(gre->gr_flags) == 1) {
3265                         hv += gre->gr_call;
3266                 }
3267                 /* FALLTHROUGH */
3268 #endif
3269         default :
3270                 ifqp = NULL;
3271                 hvm = DOUBLE_HASH(hv);
3272                 READ_ENTER(&softc->ipf_state);
3273                 for (isp = &softs->ipf_state_table[hvm];
3274                      ((is = *isp) != NULL); ) {
3275                         isp = &is->is_hnext;
3276                         if ((is->is_p != pr) || (is->is_v != v))
3277                                 continue;
3278                         is = ipf_matchsrcdst(fin, is, &src, &dst, NULL, FI_CMP);
3279                         if (is != NULL) {
3280                                 ifq = &softs->ipf_state_iptq;
3281                                 break;
3282                         }
3283                 }
3284                 if (is == NULL) {
3285                         RWLOCK_EXIT(&softc->ipf_state);
3286                 }
3287                 break;
3288         }
3289
3290         if (is != NULL) {
3291                 if (((is->is_sti.tqe_flags & TQE_RULEBASED) != 0) &&
3292                     (is->is_tqehead[fin->fin_rev] != NULL))
3293                         ifq = is->is_tqehead[fin->fin_rev];
3294                 if (ifq != NULL && ifqp != NULL)
3295                         *ifqp = ifq;
3296         } else {
3297                 SBUMP(ipf_state_stats.iss_lookup_miss);
3298         }
3299         return is;
3300 }
3301
3302
3303 /* ------------------------------------------------------------------------ */
3304 /* Function:    ipf_state_check                                             */
3305 /* Returns:     frentry_t* - NULL == search failed,                         */
3306 /*                           else pointer to rule for matching state        */
3307 /* Parameters:  fin(I)   - pointer to packet information                    */
3308 /*              passp(I) - pointer to filtering result flags                */
3309 /*                                                                          */
3310 /* Check if a packet is associated with an entry in the state table.        */
3311 /* ------------------------------------------------------------------------ */
3312 frentry_t *
3313 ipf_state_check(fin, passp)
3314         fr_info_t *fin;
3315         u_32_t *passp;
3316 {
3317         ipf_main_softc_t *softc = fin->fin_main_soft;
3318         ipf_state_softc_t *softs = softc->ipf_state_soft;
3319         ipftqent_t *tqe;
3320         ipstate_t *is;
3321         frentry_t *fr;
3322         tcphdr_t *tcp;
3323         ipftq_t *ifq;
3324         u_int pass;
3325         int inout;
3326
3327         if (softs->ipf_state_lock || (softs->ipf_state_list == NULL))
3328                 return NULL;
3329
3330         if (fin->fin_flx & (FI_SHORT|FI_FRAGBODY|FI_BAD)) {
3331                 SBUMPD(ipf_state_stats, iss_check_bad);
3332                 return NULL;
3333         }
3334
3335         if ((fin->fin_flx & FI_TCPUDP) ||
3336             (fin->fin_fi.fi_p == IPPROTO_ICMP)
3337 #ifdef  USE_INET6
3338             || (fin->fin_fi.fi_p == IPPROTO_ICMPV6)
3339 #endif
3340             )
3341                 tcp = fin->fin_dp;
3342         else
3343                 tcp = NULL;
3344
3345         ifq = NULL;
3346         /*
3347          * Search the hash table for matching packet header info.
3348          */
3349         is = ipf_state_lookup(fin, tcp, &ifq);
3350
3351         switch (fin->fin_p)
3352         {
3353 #ifdef  USE_INET6
3354         case IPPROTO_ICMPV6 :
3355                 if (is != NULL)
3356                         break;
3357                 if (fin->fin_v == 6) {
3358                         is = ipf_checkicmp6matchingstate(fin);
3359                 }
3360                 break;
3361 #endif
3362         case IPPROTO_ICMP :
3363                 if (is != NULL)
3364                         break;
3365                 /*
3366                  * No matching icmp state entry. Perhaps this is a
3367                  * response to another state entry.
3368                  */
3369                 is = ipf_checkicmpmatchingstate(fin);
3370                 break;
3371
3372         case IPPROTO_TCP :
3373                 if (is == NULL)
3374                         break;
3375
3376                 if (is->is_pass & FR_NEWISN) {
3377                         if (fin->fin_out == 0)
3378                                 ipf_fixinisn(fin, is);
3379                         else if (fin->fin_out == 1)
3380                                 ipf_fixoutisn(fin, is);
3381                 }
3382                 break;
3383         default :
3384                 if (fin->fin_rev)
3385                         ifq = &softs->ipf_state_udpacktq;
3386                 else
3387                         ifq = &softs->ipf_state_udptq;
3388                 break;
3389         }
3390         if (is == NULL) {
3391                 SBUMP(ipf_state_stats.iss_check_miss);
3392                 return NULL;
3393         }
3394
3395         fr = is->is_rule;
3396         if (fr != NULL) {
3397                 if ((fin->fin_out == 0) && (fr->fr_nattag.ipt_num[0] != 0)) {
3398                         if (fin->fin_nattag == NULL) {
3399                                 RWLOCK_EXIT(&softc->ipf_state);
3400                                 SBUMPD(ipf_state_stats, iss_check_notag);
3401                                 return NULL;
3402                         }
3403                         if (ipf_matchtag(&fr->fr_nattag, fin->fin_nattag)!=0) {
3404                                 RWLOCK_EXIT(&softc->ipf_state);
3405                                 SBUMPD(ipf_state_stats, iss_check_nattag);
3406                                 return NULL;
3407                         }
3408                 }
3409                 (void) strncpy(fin->fin_group, FR_NAME(fr, fr_group),
3410                                FR_GROUPLEN);
3411                 fin->fin_icode = fr->fr_icode;
3412         }
3413
3414         fin->fin_rule = is->is_rulen;
3415         fin->fin_fr = fr;
3416
3417         /*
3418          * If this packet is a fragment and the rule says to track fragments,
3419          * then create a new fragment cache entry.
3420          */
3421         if (fin->fin_flx & FI_FRAG && FR_ISPASS(is->is_pass) &&
3422            is->is_pass & FR_KEEPFRAG)
3423                 (void) ipf_frag_new(softc, fin, is->is_pass);
3424
3425         /*
3426          * For TCP packets, ifq == NULL.  For all others, check if this new
3427          * queue is different to the last one it was on and move it if so.
3428          */
3429         tqe = &is->is_sti;
3430         if ((tqe->tqe_flags & TQE_RULEBASED) != 0)
3431                 ifq = is->is_tqehead[fin->fin_rev];
3432
3433         MUTEX_ENTER(&is->is_lock);
3434
3435         if (ifq != NULL)
3436                 ipf_movequeue(softc->ipf_ticks, tqe, tqe->tqe_ifq, ifq);
3437
3438         inout = (fin->fin_rev << 1) + fin->fin_out;
3439         is->is_pkts[inout]++;
3440         is->is_bytes[inout] += fin->fin_plen;
3441         fin->fin_pktnum = is->is_pkts[inout] + is->is_icmppkts[inout];
3442
3443         MUTEX_EXIT(&is->is_lock);
3444
3445         pass = is->is_pass;
3446
3447         if (is->is_flags & IS_STATESYNC)
3448                 ipf_sync_update(softc, SMC_STATE, fin, is->is_sync);
3449
3450         RWLOCK_EXIT(&softc->ipf_state);
3451
3452         SBUMP(ipf_state_stats.iss_hits);
3453
3454         fin->fin_dif = &is->is_dif;
3455         fin->fin_tif = &is->is_tifs[fin->fin_rev];
3456         fin->fin_flx |= FI_STATE;
3457         if ((pass & FR_LOGFIRST) != 0)
3458                 pass &= ~(FR_LOGFIRST|FR_LOG);
3459         *passp = pass;
3460         return fr;
3461 }
3462
3463
3464 /* ------------------------------------------------------------------------ */
3465 /* Function:    ipf_fixoutisn                                               */
3466 /* Returns:     Nil                                                         */
3467 /* Parameters:  fin(I) - pointer to packet information                      */
3468 /*              is(I)  - pointer to master state structure                  */
3469 /*                                                                          */
3470 /* Called only for outbound packets, adjusts the sequence number and the    */
3471 /* TCP checksum to match that change.                                       */
3472 /* ------------------------------------------------------------------------ */
3473 static void
3474 ipf_fixoutisn(fin, is)
3475         fr_info_t *fin;
3476         ipstate_t *is;
3477 {
3478         tcphdr_t *tcp;
3479         int rev;
3480         u_32_t seq;
3481
3482         tcp = fin->fin_dp;
3483         rev = fin->fin_rev;
3484         if ((is->is_flags & IS_ISNSYN) != 0) {
3485                 if ((rev == 0) && (fin->fin_cksum < FI_CK_L4PART)) {
3486                         seq = ntohl(tcp->th_seq);
3487                         seq += is->is_isninc[0];
3488                         tcp->th_seq = htonl(seq);
3489                         ipf_fix_outcksum(0, &tcp->th_sum, is->is_sumd[0], 0);
3490                 }
3491         }
3492         if ((is->is_flags & IS_ISNACK) != 0) {
3493                 if ((rev == 1) && (fin->fin_cksum < FI_CK_L4PART)) {
3494                         seq = ntohl(tcp->th_seq);
3495                         seq += is->is_isninc[1];
3496                         tcp->th_seq = htonl(seq);
3497                         ipf_fix_outcksum(0, &tcp->th_sum, is->is_sumd[1], 0);
3498                 }
3499         }
3500 }
3501
3502
3503 /* ------------------------------------------------------------------------ */
3504 /* Function:    ipf_fixinisn                                                */
3505 /* Returns:     Nil                                                         */
3506 /* Parameters:  fin(I)   - pointer to packet information                    */
3507 /*              is(I)  - pointer to master state structure                  */
3508 /*                                                                          */
3509 /* Called only for inbound packets, adjusts the acknowledge number and the  */
3510 /* TCP checksum to match that change.                                       */
3511 /* ------------------------------------------------------------------------ */
3512 static void
3513 ipf_fixinisn(fin, is)
3514         fr_info_t *fin;
3515         ipstate_t *is;
3516 {
3517         tcphdr_t *tcp;
3518         int rev;
3519         u_32_t ack;
3520
3521         tcp = fin->fin_dp;
3522         rev = fin->fin_rev;
3523         if ((is->is_flags & IS_ISNSYN) != 0) {
3524                 if ((rev == 1) && (fin->fin_cksum < FI_CK_L4PART)) {
3525                         ack = ntohl(tcp->th_ack);
3526                         ack -= is->is_isninc[0];
3527                         tcp->th_ack = htonl(ack);
3528                         ipf_fix_incksum(0, &tcp->th_sum, is->is_sumd[0], 0);
3529                 }
3530         }
3531         if ((is->is_flags & IS_ISNACK) != 0) {
3532                 if ((rev == 0) && (fin->fin_cksum < FI_CK_L4PART)) {
3533                         ack = ntohl(tcp->th_ack);
3534                         ack -= is->is_isninc[1];
3535                         tcp->th_ack = htonl(ack);
3536                         ipf_fix_incksum(0, &tcp->th_sum, is->is_sumd[1], 0);
3537                 }
3538         }
3539 }
3540
3541
3542 /* ------------------------------------------------------------------------ */
3543 /* Function:    ipf_state_sync                                              */
3544 /* Returns:     Nil                                                         */
3545 /* Parameters:  softc(I) - pointer to soft context main structure           */
3546 /*              ifp(I)   - pointer to interface                             */
3547 /*                                                                          */
3548 /* Walk through all state entries and if an interface pointer match is      */
3549 /* found then look it up again, based on its name in case the pointer has   */
3550 /* changed since last time.                                                 */
3551 /*                                                                          */
3552 /* If ifp is passed in as being non-null then we are only doing updates for */
3553 /* existing, matching, uses of it.                                          */
3554 /* ------------------------------------------------------------------------ */
3555 void
3556 ipf_state_sync(softc, ifp)
3557         ipf_main_softc_t *softc;
3558         void *ifp;
3559 {
3560         ipf_state_softc_t *softs = softc->ipf_state_soft;
3561         ipstate_t *is;
3562         int i;
3563
3564         if (softc->ipf_running <= 0)
3565                 return;
3566
3567         WRITE_ENTER(&softc->ipf_state);
3568
3569         if (softc->ipf_running <= 0) {
3570                 RWLOCK_EXIT(&softc->ipf_state);
3571                 return;
3572         }
3573
3574         for (is = softs->ipf_state_list; is; is = is->is_next) {
3575                 /*
3576                  * Look up all the interface names in the state entry.
3577                  */
3578                 for (i = 0; i < 4; i++) {
3579                         if (ifp == NULL || ifp == is->is_ifp[i])
3580                                 is->is_ifp[i] = ipf_resolvenic(softc,
3581                                                               is->is_ifname[i],
3582                                                               is->is_v);
3583                 }
3584         }
3585         RWLOCK_EXIT(&softc->ipf_state);
3586 }
3587
3588
3589 /* ------------------------------------------------------------------------ */
3590 /* Function:    ipf_state_del                                               */
3591 /* Returns:     int    - 0 = deleted, else refernce count on active struct  */
3592 /* Parameters:  softc(I) - pointer to soft context main structure           */
3593 /*              is(I)  - pointer to state structure to delete               */
3594 /*              why(I) - if not 0, log reason why it was deleted            */
3595 /* Write Locks: ipf_state                                                   */
3596 /*                                                                          */
3597 /* Deletes a state entry from the enumerated list as well as the hash table */
3598 /* and timeout queue lists.  Make adjustments to hash table statistics and  */
3599 /* global counters as required.                                             */
3600 /* ------------------------------------------------------------------------ */
3601 static int
3602 ipf_state_del(softc, is, why)
3603         ipf_main_softc_t *softc;
3604         ipstate_t *is;
3605         int why;
3606 {
3607         ipf_state_softc_t *softs = softc->ipf_state_soft;
3608         int orphan = 1;
3609         frentry_t *fr;
3610
3611         /*
3612          * Since we want to delete this, remove it from the state table,
3613          * where it can be found & used, first.
3614          */
3615         if (is->is_phnext != NULL) {
3616                 *is->is_phnext = is->is_hnext;
3617                 if (is->is_hnext != NULL)
3618                         is->is_hnext->is_phnext = is->is_phnext;
3619                 if (softs->ipf_state_table[is->is_hv] == NULL)
3620                         softs->ipf_state_stats.iss_inuse--;
3621                 softs->ipf_state_stats.iss_bucketlen[is->is_hv]--;
3622
3623                 is->is_phnext = NULL;
3624                 is->is_hnext = NULL;
3625                 orphan = 0;
3626         }
3627
3628         /*
3629          * Because ipf_state_stats.iss_wild is a count of entries in the state
3630          * table that have wildcard flags set, only decerement it once
3631          * and do it here.
3632          */
3633         if (is->is_flags & (SI_WILDP|SI_WILDA)) {
3634                 if (!(is->is_flags & SI_CLONED)) {
3635                         ATOMIC_DECL(softs->ipf_state_stats.iss_wild);
3636                 }
3637                 is->is_flags &= ~(SI_WILDP|SI_WILDA);
3638         }
3639
3640         /*
3641          * Next, remove it from the timeout queue it is in.
3642          */
3643         if (is->is_sti.tqe_ifq != NULL)
3644                 ipf_deletequeueentry(&is->is_sti);
3645
3646         /*
3647          * If it is still in use by something else, do not go any further,
3648          * but note that at this point it is now an orphan.  How can this
3649          * be?  ipf_state_flush() calls ipf_delete() directly because it wants
3650          * to empty the table out and if something has a hold on a state
3651          * entry (such as ipfstat), it'll do the deref path that'll bring
3652          * us back here to do the real delete & free.
3653          */
3654         MUTEX_ENTER(&is->is_lock);
3655         if (is->is_me != NULL) {
3656                 *is->is_me = NULL;
3657                 is->is_me = NULL;
3658                 is->is_ref--;
3659         }
3660         is->is_ref--;
3661         if (is->is_ref > 0) {
3662                 int refs;
3663
3664                 refs = is->is_ref;
3665                 MUTEX_EXIT(&is->is_lock);
3666                 if (!orphan)
3667                         softs->ipf_state_stats.iss_orphan++;
3668                 return refs;
3669         }
3670
3671         fr = is->is_rule;
3672         is->is_rule = NULL;
3673         if (fr != NULL) {
3674                 if (fr->fr_srctrack.ht_max_nodes != 0) {
3675                         (void) ipf_ht_node_del(&fr->fr_srctrack,
3676                                                is->is_family, &is->is_src);
3677                 }
3678         }
3679
3680         ASSERT(is->is_ref == 0);
3681         MUTEX_EXIT(&is->is_lock);
3682
3683         if (is->is_tqehead[0] != NULL) {
3684                 if (ipf_deletetimeoutqueue(is->is_tqehead[0]) == 0)
3685                         ipf_freetimeoutqueue(softc, is->is_tqehead[0]);
3686         }
3687         if (is->is_tqehead[1] != NULL) {
3688                 if (ipf_deletetimeoutqueue(is->is_tqehead[1]) == 0)
3689                         ipf_freetimeoutqueue(softc, is->is_tqehead[1]);
3690         }
3691
3692         if (is->is_sync)
3693                 ipf_sync_del_state(softc->ipf_sync_soft, is->is_sync);
3694
3695         /*
3696          * Now remove it from the linked list of known states
3697          */
3698         if (is->is_pnext != NULL) {
3699                 *is->is_pnext = is->is_next;
3700
3701                 if (is->is_next != NULL)
3702                         is->is_next->is_pnext = is->is_pnext;
3703
3704                 is->is_pnext = NULL;
3705                 is->is_next = NULL;
3706         }
3707
3708         if (softs->ipf_state_logging != 0 && why != 0)
3709                 ipf_state_log(softc, is, why);
3710
3711         if (is->is_p == IPPROTO_TCP)
3712                 softs->ipf_state_stats.iss_fin++;
3713         else
3714                 softs->ipf_state_stats.iss_expire++;
3715         if (orphan)
3716                 softs->ipf_state_stats.iss_orphan--;
3717
3718         if (fr != NULL) {
3719                 fr->fr_statecnt--;
3720                 (void) ipf_derefrule(softc, &fr);
3721         }
3722
3723         softs->ipf_state_stats.iss_active_proto[is->is_p]--;
3724
3725         MUTEX_DESTROY(&is->is_lock);
3726         KFREE(is);
3727         softs->ipf_state_stats.iss_active--;
3728
3729         return 0;
3730 }
3731
3732
3733 /* ------------------------------------------------------------------------ */
3734 /* Function:    ipf_state_expire                                            */
3735 /* Returns:     Nil                                                         */
3736 /* Parameters:  softc(I) - pointer to soft context main structure           */
3737 /*                                                                          */
3738 /* Slowly expire held state for thingslike UDP and ICMP.  The algorithm     */
3739 /* used here is to keep the queue sorted with the oldest things at the top  */
3740 /* and the youngest at the bottom.  So if the top one doesn't need to be    */
3741 /* expired then neither will any under it.                                  */
3742 /* ------------------------------------------------------------------------ */
3743 void
3744 ipf_state_expire(softc)
3745         ipf_main_softc_t *softc;
3746 {
3747         ipf_state_softc_t *softs = softc->ipf_state_soft;
3748         ipftq_t *ifq, *ifqnext;
3749         ipftqent_t *tqe, *tqn;
3750         ipstate_t *is;
3751         SPL_INT(s);
3752
3753         SPL_NET(s);
3754         WRITE_ENTER(&softc->ipf_state);
3755         for (ifq = softs->ipf_state_tcptq; ifq != NULL; ifq = ifq->ifq_next)
3756                 for (tqn = ifq->ifq_head; ((tqe = tqn) != NULL); ) {
3757                         if (tqe->tqe_die > softc->ipf_ticks)
3758                                 break;
3759                         tqn = tqe->tqe_next;
3760                         is = tqe->tqe_parent;
3761                         ipf_state_del(softc, is, ISL_EXPIRE);
3762                 }
3763
3764         for (ifq = softs->ipf_state_usertq; ifq != NULL; ifq = ifqnext) {
3765                 ifqnext = ifq->ifq_next;
3766
3767                 for (tqn = ifq->ifq_head; ((tqe = tqn) != NULL); ) {
3768                         if (tqe->tqe_die > softc->ipf_ticks)
3769                                 break;
3770                         tqn = tqe->tqe_next;
3771                         is = tqe->tqe_parent;
3772                         ipf_state_del(softc, is, ISL_EXPIRE);
3773                 }
3774         }
3775
3776         for (ifq = softs->ipf_state_usertq; ifq != NULL; ifq = ifqnext) {
3777                 ifqnext = ifq->ifq_next;
3778
3779                 if (((ifq->ifq_flags & IFQF_DELETE) != 0) &&
3780                     (ifq->ifq_ref == 0)) {
3781                         ipf_freetimeoutqueue(softc, ifq);
3782                 }
3783         }
3784
3785         if (softs->ipf_state_doflush) {
3786                 (void) ipf_state_flush(softc, 2, 0);
3787                 softs->ipf_state_doflush = 0;
3788                 softs->ipf_state_wm_last = softc->ipf_ticks;
3789         }
3790
3791         RWLOCK_EXIT(&softc->ipf_state);
3792         SPL_X(s);
3793 }
3794
3795
3796 /* ------------------------------------------------------------------------ */
3797 /* Function:    ipf_state_flush                                             */
3798 /* Returns:     int - 0 == success, -1 == failure                           */
3799 /* Parameters:  softc(I) - pointer to soft context main structure           */
3800 /*              which(I) - which flush action to perform                    */
3801 /*              proto(I) - which protocol to flush (0 == ALL)               */
3802 /* Write Locks: ipf_state                                                   */
3803 /*                                                                          */
3804 /* Flush state tables.  Three actions currently defined:                    */
3805 /* which == 0 : flush all state table entries                               */
3806 /* which == 1 : flush TCP connections which have started to close but are   */
3807 /*            stuck for some reason.                                        */
3808 /* which == 2 : flush TCP connections which have been idle for a long time, */
3809 /*            starting at > 4 days idle and working back in successive half-*/
3810 /*            days to at most 12 hours old.  If this fails to free enough   */
3811 /*            slots then work backwards in half hour slots to 30 minutes.   */
3812 /*            If that too fails, then work backwards in 30 second intervals */
3813 /*            for the last 30 minutes to at worst 30 seconds idle.          */
3814 /* ------------------------------------------------------------------------ */
3815 int
3816 ipf_state_flush(softc, which, proto)
3817         ipf_main_softc_t *softc;
3818         int which, proto;
3819 {
3820         ipf_state_softc_t *softs = softc->ipf_state_soft;
3821         ipftqent_t *tqe, *tqn;
3822         ipstate_t *is, **isp;
3823         ipftq_t *ifq;
3824         int removed;
3825         SPL_INT(s);
3826
3827         removed = 0;
3828
3829         SPL_NET(s);
3830
3831         switch (which)
3832         {
3833         case 0 :
3834                 SBUMP(ipf_state_stats.iss_flush_all);
3835                 /*
3836                  * Style 0 flush removes everything...
3837                  */
3838                 for (isp = &softs->ipf_state_list; ((is = *isp) != NULL); ) {
3839                         if ((proto != 0) && (is->is_v != proto)) {
3840                                 isp = &is->is_next;
3841                                 continue;
3842                         }
3843                         if (ipf_state_del(softc, is, ISL_FLUSH) == 0)
3844                                 removed++;
3845                         else
3846                                 isp = &is->is_next;
3847                 }
3848                 break;
3849
3850         case 1 :
3851                 SBUMP(ipf_state_stats.iss_flush_closing);
3852                 /*
3853                  * Since we're only interested in things that are closing,
3854                  * we can start with the appropriate timeout queue.
3855                  */
3856                 for (ifq = softs->ipf_state_tcptq + IPF_TCPS_CLOSE_WAIT;
3857                      ifq != NULL; ifq = ifq->ifq_next) {
3858
3859                         for (tqn = ifq->ifq_head; ((tqe = tqn) != NULL); ) {
3860                                 tqn = tqe->tqe_next;
3861                                 is = tqe->tqe_parent;
3862                                 if (is->is_p != IPPROTO_TCP)
3863                                         break;
3864                                 if (ipf_state_del(softc, is, ISL_FLUSH) == 0)
3865                                         removed++;
3866                         }
3867                 }
3868
3869                 /*
3870                  * Also need to look through the user defined queues.
3871                  */
3872                 for (ifq = softs->ipf_state_usertq; ifq != NULL;
3873                      ifq = ifq->ifq_next) {
3874                         for (tqn = ifq->ifq_head; ((tqe = tqn) != NULL); ) {
3875                                 tqn = tqe->tqe_next;
3876                                 is = tqe->tqe_parent;
3877                                 if (is->is_p != IPPROTO_TCP)
3878                                         continue;
3879
3880                                 if ((is->is_state[0] > IPF_TCPS_ESTABLISHED) &&
3881                                     (is->is_state[1] > IPF_TCPS_ESTABLISHED)) {
3882                                         if (ipf_state_del(softc, is,
3883                                                           ISL_FLUSH) == 0)
3884                                                 removed++;
3885                                 }
3886                         }
3887                 }
3888                 break;
3889
3890         case 2 :
3891                 break;
3892
3893                 /*
3894                  * Args 5-11 correspond to flushing those particular states
3895                  * for TCP connections.
3896                  */
3897         case IPF_TCPS_CLOSE_WAIT :
3898         case IPF_TCPS_FIN_WAIT_1 :
3899         case IPF_TCPS_CLOSING :
3900         case IPF_TCPS_LAST_ACK :
3901         case IPF_TCPS_FIN_WAIT_2 :
3902         case IPF_TCPS_TIME_WAIT :
3903         case IPF_TCPS_CLOSED :
3904                 SBUMP(ipf_state_stats.iss_flush_queue);
3905                 tqn = softs->ipf_state_tcptq[which].ifq_head;
3906                 while (tqn != NULL) {
3907                         tqe = tqn;
3908                         tqn = tqe->tqe_next;
3909                         is = tqe->tqe_parent;
3910                         if (ipf_state_del(softc, is, ISL_FLUSH) == 0)
3911                                 removed++;
3912                 }
3913                 break;
3914
3915         default :
3916                 if (which < 30)
3917                         break;
3918
3919                 SBUMP(ipf_state_stats.iss_flush_state);
3920                 /*
3921                  * Take a large arbitrary number to mean the number of seconds
3922                  * for which which consider to be the maximum value we'll allow
3923                  * the expiration to be.
3924                  */
3925                 which = IPF_TTLVAL(which);
3926                 for (isp = &softs->ipf_state_list; ((is = *isp) != NULL); ) {
3927                         if ((proto == 0) || (is->is_v == proto)) {
3928                                 if (softc->ipf_ticks - is->is_touched > which) {
3929                                         if (ipf_state_del(softc, is,
3930                                                           ISL_FLUSH) == 0) {
3931                                                 removed++;
3932                                                 continue;
3933                                         }
3934                                 }
3935                         }
3936                         isp = &is->is_next;
3937                 }
3938                 break;
3939         }
3940
3941         if (which != 2) {
3942                 SPL_X(s);
3943                 return removed;
3944         }
3945
3946         SBUMP(ipf_state_stats.iss_flush_timeout);
3947         /*
3948          * Asked to remove inactive entries because the table is full, try
3949          * again, 3 times, if first attempt failed with a different criteria
3950          * each time.  The order tried in must be in decreasing age.
3951          * Another alternative is to implement random drop and drop N entries
3952          * at random until N have been freed up.
3953          */
3954         if (softc->ipf_ticks - softs->ipf_state_wm_last >
3955             softs->ipf_state_wm_freq) {
3956                 removed = ipf_queueflush(softc, ipf_state_flush_entry,
3957                                          softs->ipf_state_tcptq,
3958                                          softs->ipf_state_usertq,
3959                                          &softs->ipf_state_stats.iss_active,
3960                                          softs->ipf_state_size,
3961                                          softs->ipf_state_wm_low);
3962                 softs->ipf_state_wm_last = softc->ipf_ticks;
3963         }
3964
3965         SPL_X(s);
3966         return removed;
3967 }
3968
3969
3970 /* ------------------------------------------------------------------------ */
3971 /* Function:    ipf_state_flush_entry                                       */
3972 /* Returns:     int - 0 = entry deleted, else not deleted                   */
3973 /* Parameters:  softc(I) - pointer to soft context main structure           */
3974 /*              entry(I)  - pointer to state structure to delete            */
3975 /* Write Locks: ipf_state                                                   */
3976 /*                                                                          */
3977 /* This function is a stepping stone between ipf_queueflush() and           */
3978 /* ipf_state_del().  It is used so we can provide a uniform interface via   */
3979 /* the ipf_queueflush() function.                                           */
3980 /* ------------------------------------------------------------------------ */
3981 static int
3982 ipf_state_flush_entry(softc, entry)
3983         ipf_main_softc_t *softc;
3984         void *entry;
3985 {
3986         return ipf_state_del(softc, entry, ISL_FLUSH);
3987 }
3988
3989
3990 /* ------------------------------------------------------------------------ */
3991 /* Function:    ipf_tcp_age                                                 */
3992 /* Returns:     int - 1 == state transition made, 0 == no change (rejected) */
3993 /* Parameters:  tqe(I)   - pointer to timeout queue information             */
3994 /*              fin(I)   - pointer to packet information                    */
3995 /*              tqtab(I) - TCP timeout queue table this is in               */
3996 /*              flags(I) - flags from state/NAT entry                       */
3997 /*              ok(I)    - can we advance state                             */
3998 /*                                                                          */
3999 /* Rewritten by Arjan de Vet <Arjan.deVet@adv.iae.nl>, 2000-07-29:          */
4000 /*                                                                          */
4001 /* - (try to) base state transitions on real evidence only,                 */
4002 /*   i.e. packets that are sent and have been received by ipfilter;         */
4003 /*   diagram 18.12 of TCP/IP volume 1 by W. Richard Stevens was used.       */
4004 /*                                                                          */
4005 /* - deal with half-closed connections correctly;                           */
4006 /*                                                                          */
4007 /* - store the state of the source in state[0] such that ipfstat            */
4008 /*   displays the state as source/dest instead of dest/source; the calls    */
4009 /*   to ipf_tcp_age have been changed accordingly.                          */
4010 /*                                                                          */
4011 /* Internal Parameters:                                                     */
4012 /*                                                                          */
4013 /*    state[0] = state of source (host that initiated connection)           */
4014 /*    state[1] = state of dest   (host that accepted the connection)        */
4015 /*                                                                          */
4016 /*    dir == 0 : a packet from source to dest                               */
4017 /*    dir == 1 : a packet from dest to source                               */
4018 /*                                                                          */
4019 /* A typical procession for a connection is as follows:                     */
4020 /*                                                                          */
4021 /* +--------------+-------------------+                                     */
4022 /* | Side '0'     | Side '1'          |                                     */
4023 /* +--------------+-------------------+                                     */
4024 /* | 0 -> 1 (SYN) |                   |                                     */
4025 /* |              | 0 -> 2 (SYN-ACK)  |                                     */
4026 /* | 1 -> 3 (ACK) |                   |                                     */
4027 /* |              | 2 -> 4 (ACK-PUSH) |                                     */
4028 /* | 3 -> 4 (ACK) |                   |                                     */
4029 /* |   ...        |   ...             |                                     */
4030 /* |              | 4 -> 6 (FIN-ACK)  |                                     */
4031 /* | 4 -> 5 (ACK) |                   |                                     */
4032 /* |              | 6 -> 6 (ACK-PUSH) |                                     */
4033 /* | 5 -> 5 (ACK) |                   |                                     */
4034 /* | 5 -> 8 (FIN) |                   |                                     */
4035 /* |              | 6 -> 10 (ACK)     |                                     */
4036 /* +--------------+-------------------+                                     */
4037 /*                                                                          */
4038 /* Locking: it is assumed that the parent of the tqe structure is locked.   */
4039 /* ------------------------------------------------------------------------ */
4040 int
4041 ipf_tcp_age(tqe, fin, tqtab, flags, ok)
4042         ipftqent_t *tqe;
4043         fr_info_t *fin;
4044         ipftq_t *tqtab;
4045         int flags, ok;
4046 {
4047         ipf_main_softc_t *softc = fin->fin_main_soft;
4048         int dlen, ostate, nstate, rval, dir;
4049         u_char tcpflags;
4050         tcphdr_t *tcp;
4051
4052         tcp = fin->fin_dp;
4053
4054         rval = 0;
4055         dir = fin->fin_rev;
4056         tcpflags = tcp->th_flags;
4057         dlen = fin->fin_dlen - (TCP_OFF(tcp) << 2);
4058         ostate = tqe->tqe_state[1 - dir];
4059         nstate = tqe->tqe_state[dir];
4060
4061         if (tcpflags & TH_RST) {
4062                 if (!(tcpflags & TH_PUSH) && !dlen)
4063                         nstate = IPF_TCPS_CLOSED;
4064                 else
4065                         nstate = IPF_TCPS_CLOSE_WAIT;
4066
4067                 if (ostate <= IPF_TCPS_ESTABLISHED) {
4068                         tqe->tqe_state[1 - dir] = IPF_TCPS_CLOSE_WAIT;
4069                 }
4070                 rval = 1;
4071         } else {
4072                 switch (nstate)
4073                 {
4074                 case IPF_TCPS_LISTEN: /* 0 */
4075                         if ((tcpflags & TH_OPENING) == TH_OPENING) {
4076                                 /*
4077                                  * 'dir' received an S and sends SA in
4078                                  * response, LISTEN -> SYN_RECEIVED
4079                                  */
4080                                 nstate = IPF_TCPS_SYN_RECEIVED;
4081                                 rval = 1;
4082                         } else if ((tcpflags & TH_OPENING) == TH_SYN) {
4083                                 /* 'dir' sent S, LISTEN -> SYN_SENT */
4084                                 nstate = IPF_TCPS_SYN_SENT;
4085                                 rval = 1;
4086                         }
4087                         /*
4088                          * the next piece of code makes it possible to get
4089                          * already established connections into the state table
4090                          * after a restart or reload of the filter rules; this
4091                          * does not work when a strict 'flags S keep state' is
4092                          * used for tcp connections of course
4093                          */
4094                         if (((flags & IS_TCPFSM) == 0) &&
4095                             ((tcpflags & TH_ACKMASK) == TH_ACK)) {
4096                                 /*
4097                                  * we saw an A, guess 'dir' is in ESTABLISHED
4098                                  * mode
4099                                  */
4100                                 switch (ostate)
4101                                 {
4102                                 case IPF_TCPS_LISTEN :
4103                                 case IPF_TCPS_SYN_RECEIVED :
4104                                         nstate = IPF_TCPS_HALF_ESTAB;
4105                                         rval = 1;
4106                                         break;
4107                                 case IPF_TCPS_HALF_ESTAB :
4108                                 case IPF_TCPS_ESTABLISHED :
4109                                         nstate = IPF_TCPS_ESTABLISHED;
4110                                         rval = 1;
4111                                         break;
4112                                 default :
4113                                         break;
4114                                 }
4115                         }
4116                         /*
4117                          * TODO: besides regular ACK packets we can have other
4118                          * packets as well; it is yet to be determined how we
4119                          * should initialize the states in those cases
4120                          */
4121                         break;
4122
4123                 case IPF_TCPS_SYN_SENT: /* 1 */
4124                         if ((tcpflags & ~(TH_ECN|TH_CWR)) == TH_SYN) {
4125                                 /*
4126                                  * A retransmitted SYN packet.  We do not reset
4127                                  * the timeout here to ipf_tcptimeout because a
4128                                  * connection connect timeout does not renew
4129                                  * after every packet that is sent.  We need to
4130                                  * set rval so as to indicate the packet has
4131                                  * passed the check for its flags being valid
4132                                  * in the TCP FSM.  Setting rval to 2 has the
4133                                  * result of not resetting the timeout.
4134                                  */
4135                                 rval = 2;
4136                         } else if ((tcpflags & (TH_SYN|TH_FIN|TH_ACK)) ==
4137                                    TH_ACK) {
4138                                 /*
4139                                  * we see an A from 'dir' which is in SYN_SENT
4140                                  * state: 'dir' sent an A in response to an SA
4141                                  * which it received, SYN_SENT -> ESTABLISHED
4142                                  */
4143                                 nstate = IPF_TCPS_ESTABLISHED;
4144                                 rval = 1;
4145                         } else if (tcpflags & TH_FIN) {
4146                                 /*
4147                                  * we see an F from 'dir' which is in SYN_SENT
4148                                  * state and wants to close its side of the
4149                                  * connection; SYN_SENT -> FIN_WAIT_1
4150                                  */
4151                                 nstate = IPF_TCPS_FIN_WAIT_1;
4152                                 rval = 1;
4153                         } else if ((tcpflags & TH_OPENING) == TH_OPENING) {
4154                                 /*
4155                                  * we see an SA from 'dir' which is already in
4156                                  * SYN_SENT state, this means we have a
4157                                  * simultaneous open; SYN_SENT -> SYN_RECEIVED
4158                                  */
4159                                 nstate = IPF_TCPS_SYN_RECEIVED;
4160                                 rval = 1;
4161                         }
4162                         break;
4163
4164                 case IPF_TCPS_SYN_RECEIVED: /* 2 */
4165                         if ((tcpflags & (TH_SYN|TH_FIN|TH_ACK)) == TH_ACK) {
4166                                 /*
4167                                  * we see an A from 'dir' which was in
4168                                  * SYN_RECEIVED state so it must now be in
4169                                  * established state, SYN_RECEIVED ->
4170                                  * ESTABLISHED
4171                                  */
4172                                 nstate = IPF_TCPS_ESTABLISHED;
4173                                 rval = 1;
4174                         } else if ((tcpflags & ~(TH_ECN|TH_CWR)) ==
4175                                    TH_OPENING) {
4176                                 /*
4177                                  * We see an SA from 'dir' which is already in
4178                                  * SYN_RECEIVED state.
4179                                  */
4180                                 rval = 2;
4181                         } else if (tcpflags & TH_FIN) {
4182                                 /*
4183                                  * we see an F from 'dir' which is in
4184                                  * SYN_RECEIVED state and wants to close its
4185                                  * side of the connection; SYN_RECEIVED ->
4186                                  * FIN_WAIT_1
4187                                  */
4188                                 nstate = IPF_TCPS_FIN_WAIT_1;
4189                                 rval = 1;
4190                         }
4191                         break;
4192
4193                 case IPF_TCPS_HALF_ESTAB: /* 3 */
4194                         if (tcpflags & TH_FIN) {
4195                                 nstate = IPF_TCPS_FIN_WAIT_1;
4196                                 rval = 1;
4197                         } else if ((tcpflags & TH_ACKMASK) == TH_ACK) {
4198                                 /*
4199                                  * If we've picked up a connection in mid
4200                                  * flight, we could be looking at a follow on
4201                                  * packet from the same direction as the one
4202                                  * that created this state.  Recognise it but
4203                                  * do not advance the entire connection's
4204                                  * state.
4205                                  */
4206                                 switch (ostate)
4207                                 {
4208                                 case IPF_TCPS_LISTEN :
4209                                 case IPF_TCPS_SYN_SENT :
4210                                 case IPF_TCPS_SYN_RECEIVED :
4211                                         rval = 1;
4212                                         break;
4213                                 case IPF_TCPS_HALF_ESTAB :
4214                                 case IPF_TCPS_ESTABLISHED :
4215                                         nstate = IPF_TCPS_ESTABLISHED;
4216                                         rval = 1;
4217                                         break;
4218                                 default :
4219                                         break;
4220                                 }
4221                         }
4222                         break;
4223
4224                 case IPF_TCPS_ESTABLISHED: /* 4 */
4225                         rval = 1;
4226                         if (tcpflags & TH_FIN) {
4227                                 /*
4228                                  * 'dir' closed its side of the connection;
4229                                  * this gives us a half-closed connection;
4230                                  * ESTABLISHED -> FIN_WAIT_1
4231                                  */
4232                                 if (ostate == IPF_TCPS_FIN_WAIT_1) {
4233                                         nstate = IPF_TCPS_CLOSING;
4234                                 } else {
4235                                         nstate = IPF_TCPS_FIN_WAIT_1;
4236                                 }
4237                         } else if (tcpflags & TH_ACK) {
4238                                 /*
4239                                  * an ACK, should we exclude other flags here?
4240                                  */
4241                                 if (ostate == IPF_TCPS_FIN_WAIT_1) {
4242                                         /*
4243                                          * We know the other side did an active
4244                                          * close, so we are ACKing the recvd
4245                                          * FIN packet (does the window matching
4246                                          * code guarantee this?) and go into
4247                                          * CLOSE_WAIT state; this gives us a
4248                                          * half-closed connection
4249                                          */
4250                                         nstate = IPF_TCPS_CLOSE_WAIT;
4251                                 } else if (ostate < IPF_TCPS_CLOSE_WAIT) {
4252                                         /*
4253                                          * still a fully established
4254                                          * connection reset timeout
4255                                          */
4256                                         nstate = IPF_TCPS_ESTABLISHED;
4257                                 }
4258                         }
4259                         break;
4260
4261                 case IPF_TCPS_CLOSE_WAIT: /* 5 */
4262                         rval = 1;
4263                         if (tcpflags & TH_FIN) {
4264                                 /*
4265                                  * application closed and 'dir' sent a FIN,
4266                                  * we're now going into LAST_ACK state
4267                                  */
4268                                 nstate = IPF_TCPS_LAST_ACK;
4269                         } else {
4270                                 /*
4271                                  * we remain in CLOSE_WAIT because the other
4272                                  * side has closed already and we did not
4273                                  * close our side yet; reset timeout
4274                                  */
4275                                 nstate = IPF_TCPS_CLOSE_WAIT;
4276                         }
4277                         break;
4278
4279                 case IPF_TCPS_FIN_WAIT_1: /* 6 */
4280                         rval = 1;
4281                         if ((tcpflags & TH_ACK) &&
4282                             ostate > IPF_TCPS_CLOSE_WAIT) {
4283                                 /*
4284                                  * if the other side is not active anymore
4285                                  * it has sent us a FIN packet that we are
4286                                  * ack'ing now with an ACK; this means both
4287                                  * sides have now closed the connection and
4288                                  * we go into TIME_WAIT
4289                                  */
4290                                 /*
4291                                  * XXX: how do we know we really are ACKing
4292                                  * the FIN packet here? does the window code
4293                                  * guarantee that?
4294                                  */
4295                                 nstate = IPF_TCPS_LAST_ACK;
4296                         } else {
4297                                 /*
4298                                  * we closed our side of the connection
4299                                  * already but the other side is still active
4300                                  * (ESTABLISHED/CLOSE_WAIT); continue with
4301                                  * this half-closed connection
4302                                  */
4303                                 nstate = IPF_TCPS_FIN_WAIT_1;
4304                         }
4305                         break;
4306
4307                 case IPF_TCPS_CLOSING: /* 7 */
4308                         if ((tcpflags & (TH_FIN|TH_ACK)) == TH_ACK) {
4309                                 nstate = IPF_TCPS_TIME_WAIT;
4310                         }
4311                         rval = 1;
4312                         break;
4313
4314                 case IPF_TCPS_LAST_ACK: /* 8 */
4315                         if (tcpflags & TH_ACK) {
4316                                 rval = 1;
4317                         }
4318                         /*
4319                          * we cannot detect when we go out of LAST_ACK state
4320                          * to CLOSED because that is based on the reception
4321                          * of ACK packets; ipfilter can only detect that a
4322                          * packet has been sent by a host
4323                          */
4324                         break;
4325
4326                 case IPF_TCPS_FIN_WAIT_2: /* 9 */
4327                         /* NOT USED */
4328                         break;
4329
4330                 case IPF_TCPS_TIME_WAIT: /* 10 */
4331                         /* we're in 2MSL timeout now */
4332                         if (ostate == IPF_TCPS_LAST_ACK) {
4333                                 nstate = IPF_TCPS_CLOSED;
4334                                 rval = 1;
4335                         } else {
4336                                 rval = 2;
4337                         }
4338                         break;
4339
4340                 case IPF_TCPS_CLOSED: /* 11 */
4341                         rval = 2;
4342                         break;
4343
4344                 default :
4345 #if !defined(_KERNEL)
4346                         abort();
4347 #endif
4348                         break;
4349                 }
4350         }
4351
4352         /*
4353          * If rval == 2 then do not update the queue position, but treat the
4354          * packet as being ok.
4355          */
4356         if (rval == 2)
4357                 rval = 1;
4358         else if (rval == 1) {
4359                 if (ok)
4360                         tqe->tqe_state[dir] = nstate;
4361                 if ((tqe->tqe_flags & TQE_RULEBASED) == 0)
4362                         ipf_movequeue(softc->ipf_ticks, tqe, tqe->tqe_ifq,
4363                                       tqtab + nstate);
4364         }
4365
4366         return rval;
4367 }
4368
4369
4370 /* ------------------------------------------------------------------------ */
4371 /* Function:    ipf_state_log                                               */
4372 /* Returns:     Nil                                                         */
4373 /* Parameters:  softc(I) - pointer to soft context main structure           */
4374 /*              is(I)    - pointer to state structure                       */
4375 /*              type(I)  - type of log entry to create                      */
4376 /*                                                                          */
4377 /* Creates a state table log entry using the state structure and type info. */
4378 /* passed in.  Log packet/byte counts, source/destination address and other */
4379 /* protocol specific information.                                           */
4380 /* ------------------------------------------------------------------------ */
4381 void
4382 ipf_state_log(softc, is, type)
4383         ipf_main_softc_t *softc;
4384         struct ipstate *is;
4385         u_int type;
4386 {
4387 #ifdef  IPFILTER_LOG
4388         struct  ipslog  ipsl;
4389         size_t sizes[1];
4390         void *items[1];
4391         int types[1];
4392
4393         /*
4394          * Copy information out of the ipstate_t structure and into the
4395          * structure used for logging.
4396          */
4397         ipsl.isl_type = type;
4398         ipsl.isl_pkts[0] = is->is_pkts[0] + is->is_icmppkts[0];
4399         ipsl.isl_bytes[0] = is->is_bytes[0];
4400         ipsl.isl_pkts[1] = is->is_pkts[1] + is->is_icmppkts[1];
4401         ipsl.isl_bytes[1] = is->is_bytes[1];
4402         ipsl.isl_pkts[2] = is->is_pkts[2] + is->is_icmppkts[2];
4403         ipsl.isl_bytes[2] = is->is_bytes[2];
4404         ipsl.isl_pkts[3] = is->is_pkts[3] + is->is_icmppkts[3];
4405         ipsl.isl_bytes[3] = is->is_bytes[3];
4406         ipsl.isl_src = is->is_src;
4407         ipsl.isl_dst = is->is_dst;
4408         ipsl.isl_p = is->is_p;
4409         ipsl.isl_v = is->is_v;
4410         ipsl.isl_flags = is->is_flags;
4411         ipsl.isl_tag = is->is_tag;
4412         ipsl.isl_rulen = is->is_rulen;
4413         (void) strncpy(ipsl.isl_group, is->is_group, FR_GROUPLEN);
4414
4415         if (ipsl.isl_p == IPPROTO_TCP || ipsl.isl_p == IPPROTO_UDP) {
4416                 ipsl.isl_sport = is->is_sport;
4417                 ipsl.isl_dport = is->is_dport;
4418                 if (ipsl.isl_p == IPPROTO_TCP) {
4419                         ipsl.isl_state[0] = is->is_state[0];
4420                         ipsl.isl_state[1] = is->is_state[1];
4421                 }
4422         } else if (ipsl.isl_p == IPPROTO_ICMP) {
4423                 ipsl.isl_itype = is->is_icmp.ici_type;
4424         } else if (ipsl.isl_p == IPPROTO_ICMPV6) {
4425                 ipsl.isl_itype = is->is_icmp.ici_type;
4426         } else {
4427                 ipsl.isl_ps.isl_filler[0] = 0;
4428                 ipsl.isl_ps.isl_filler[1] = 0;
4429         }
4430
4431         items[0] = &ipsl;
4432         sizes[0] = sizeof(ipsl);
4433         types[0] = 0;
4434
4435         (void) ipf_log_items(softc, IPL_LOGSTATE, NULL, items, sizes, types, 1);
4436 #endif
4437 }
4438
4439
4440 #ifdef  USE_INET6
4441 /* ------------------------------------------------------------------------ */
4442 /* Function:    ipf_checkicmp6matchingstate                                 */
4443 /* Returns:     ipstate_t* - NULL == no match found,                        */
4444 /*                           else  pointer to matching state entry          */
4445 /* Parameters:  fin(I) - pointer to packet information                      */
4446 /* Locks:       NULL == no locks, else Read Lock on ipf_state               */
4447 /*                                                                          */
4448 /* If we've got an ICMPv6 error message, using the information stored in    */
4449 /* the ICMPv6 packet, look for a matching state table entry.                */
4450 /* ------------------------------------------------------------------------ */
4451 static ipstate_t *
4452 ipf_checkicmp6matchingstate(fin)
4453         fr_info_t *fin;
4454 {
4455         ipf_main_softc_t *softc = fin->fin_main_soft;
4456         ipf_state_softc_t *softs = softc->ipf_state_soft;
4457         struct icmp6_hdr *ic6, *oic;
4458         ipstate_t *is, **isp;
4459         u_short sport, dport;
4460         i6addr_t dst, src;
4461         u_short savelen;
4462         icmpinfo_t *ic;
4463         fr_info_t ofin;
4464         tcphdr_t *tcp;
4465         ip6_t *oip6;
4466         u_char pr;
4467         u_int hv;
4468         int type;
4469
4470         /*
4471          * Does it at least have the return (basic) IP header ?
4472          * Is it an actual recognised ICMP error type?
4473          * Only a basic IP header (no options) should be with
4474          * an ICMP error header.
4475          */
4476         if ((fin->fin_v != 6) || (fin->fin_plen < ICMP6ERR_MINPKTLEN) ||
4477             !(fin->fin_flx & FI_ICMPERR)) {
4478                 SBUMPD(ipf_state_stats, iss_icmp_bad);
4479                 return NULL;
4480         }
4481
4482         ic6 = fin->fin_dp;
4483         type = ic6->icmp6_type;
4484
4485         oip6 = (ip6_t *)((char *)ic6 + ICMPERR_ICMPHLEN);
4486         if (fin->fin_plen < sizeof(*oip6)) {
4487                 SBUMPD(ipf_state_stats, iss_icmp_short);
4488                 return NULL;
4489         }
4490
4491         bcopy((char *)fin, (char *)&ofin, sizeof(*fin));
4492         ofin.fin_v = 6;
4493         ofin.fin_ifp = fin->fin_ifp;
4494         ofin.fin_out = !fin->fin_out;
4495         ofin.fin_m = NULL;      /* if dereferenced, panic XXX */
4496         ofin.fin_mp = NULL;     /* if dereferenced, panic XXX */
4497
4498         /*
4499          * We make a fin entry to be able to feed it to
4500          * matchsrcdst. Note that not all fields are necessary
4501          * but this is the cleanest way. Note further we fill
4502          * in fin_mp such that if someone uses it we'll get
4503          * a kernel panic. ipf_matchsrcdst does not use this.
4504          *
4505          * watch out here, as ip is in host order and oip6 in network
4506          * order. Any change we make must be undone afterwards.
4507          */
4508         savelen = oip6->ip6_plen;
4509         oip6->ip6_plen = htons(fin->fin_dlen - ICMPERR_ICMPHLEN);
4510         ofin.fin_flx = FI_NOCKSUM;
4511         ofin.fin_ip = (ip_t *)oip6;
4512         (void) ipf_makefrip(sizeof(*oip6), (ip_t *)oip6, &ofin);
4513         ofin.fin_flx &= ~(FI_BAD|FI_SHORT);
4514         oip6->ip6_plen = savelen;
4515         pr = ofin.fin_p;
4516
4517         /*
4518          * an ICMP error can never generate an ICMP error in response.
4519          */
4520         if (ofin.fin_flx & FI_ICMPERR) {
4521                 DT1(iss_icmp6_icmperr, fr_info_t *, &ofin);
4522                 SBUMP(ipf_state_stats.iss_icmp6_icmperr);
4523                 return NULL;
4524         }
4525
4526         if (oip6->ip6_nxt == IPPROTO_ICMPV6) {
4527                 oic = ofin.fin_dp;
4528                 /*
4529                  * an ICMP error can only be generated as a result of an
4530                  * ICMP query, not as the response on an ICMP error
4531                  *
4532                  * XXX theoretically ICMP_ECHOREP and the other reply's are
4533                  * ICMP query's as well, but adding them here seems strange XXX
4534                  */
4535                  if (!(oic->icmp6_type & ICMP6_INFOMSG_MASK)) {
4536                         DT1(iss_icmp6_notinfo, fr_info_t *, &ofin);
4537                         SBUMP(ipf_state_stats.iss_icmp6_notinfo);
4538                         return NULL;
4539                 }
4540
4541                 /*
4542                  * perform a lookup of the ICMP packet in the state table
4543                  */
4544                 hv = (pr = oip6->ip6_nxt);
4545                 src.in6 = oip6->ip6_src;
4546                 hv += src.in4.s_addr;
4547                 dst.in6 = oip6->ip6_dst;
4548                 hv += dst.in4.s_addr;
4549                 hv += oic->icmp6_id;
4550                 hv += oic->icmp6_seq;
4551                 hv = DOUBLE_HASH(hv);
4552
4553                 READ_ENTER(&softc->ipf_state);
4554                 for (isp = &softs->ipf_state_table[hv];
4555                      ((is = *isp) != NULL); ) {
4556                         ic = &is->is_icmp;
4557                         isp = &is->is_hnext;
4558                         if ((is->is_p == pr) &&
4559                             !(is->is_pass & FR_NOICMPERR) &&
4560                             (oic->icmp6_id == ic->ici_id) &&
4561                             (oic->icmp6_seq == ic->ici_seq) &&
4562                             (is = ipf_matchsrcdst(&ofin, is, &src,
4563                                                  &dst, NULL, FI_ICMPCMP))) {
4564                                 /*
4565                                  * in the state table ICMP query's are stored
4566                                  * with the type of the corresponding ICMP
4567                                  * response. Correct here
4568                                  */
4569                                 if (((ic->ici_type == ICMP6_ECHO_REPLY) &&
4570                                      (oic->icmp6_type == ICMP6_ECHO_REQUEST)) ||
4571                                      (ic->ici_type - 1 == oic->icmp6_type )) {
4572                                         if (!ipf_allowstateicmp(fin, is, &src))
4573                                                 return is;
4574                                 }
4575                         }
4576                 }
4577                 RWLOCK_EXIT(&softc->ipf_state);
4578                 SBUMPD(ipf_state_stats, iss_icmp6_miss);
4579                 return NULL;
4580         }
4581
4582         hv = (pr = oip6->ip6_nxt);
4583         src.in6 = oip6->ip6_src;
4584         hv += src.i6[0];
4585         hv += src.i6[1];
4586         hv += src.i6[2];
4587         hv += src.i6[3];
4588         dst.in6 = oip6->ip6_dst;
4589         hv += dst.i6[0];
4590         hv += dst.i6[1];
4591         hv += dst.i6[2];
4592         hv += dst.i6[3];
4593
4594         tcp = NULL;
4595
4596         switch (oip6->ip6_nxt)
4597         {
4598         case IPPROTO_TCP :
4599         case IPPROTO_UDP :
4600                 tcp = (tcphdr_t *)(oip6 + 1);
4601                 dport = tcp->th_dport;
4602                 sport = tcp->th_sport;
4603                 hv += dport;
4604                 hv += sport;
4605                 break;
4606
4607         case IPPROTO_ICMPV6 :
4608                 oic = (struct icmp6_hdr *)(oip6 + 1);
4609                 hv += oic->icmp6_id;
4610                 hv += oic->icmp6_seq;
4611                 break;
4612
4613         default :
4614                 break;
4615         }
4616
4617         hv = DOUBLE_HASH(hv);
4618
4619         READ_ENTER(&softc->ipf_state);
4620         for (isp = &softs->ipf_state_table[hv]; ((is = *isp) != NULL); ) {
4621                 isp = &is->is_hnext;
4622                 /*
4623                  * Only allow this icmp though if the
4624                  * encapsulated packet was allowed through the
4625                  * other way around. Note that the minimal amount
4626                  * of info present does not allow for checking against
4627                  * tcp internals such as seq and ack numbers.
4628                  */
4629                 if ((is->is_p != pr) || (is->is_v != 6) ||
4630                     (is->is_pass & FR_NOICMPERR))
4631                         continue;
4632                 is = ipf_matchsrcdst(&ofin, is, &src, &dst, tcp, FI_ICMPCMP);
4633                 if ((is != NULL) && (ipf_allowstateicmp(fin, is, &src) == 0))
4634                         return is;
4635         }
4636         RWLOCK_EXIT(&softc->ipf_state);
4637         SBUMPD(ipf_state_stats, iss_icmp_miss);
4638         return NULL;
4639 }
4640 #endif
4641
4642
4643 /* ------------------------------------------------------------------------ */
4644 /* Function:    ipf_sttab_init                                              */
4645 /* Returns:     Nil                                                         */
4646 /* Parameters:  softc(I) - pointer to soft context main structure           */
4647 /*              tqp(I)   - pointer to an array of timeout queues for TCP    */
4648 /*                                                                          */
4649 /* Initialise the array of timeout queues for TCP.                          */
4650 /* ------------------------------------------------------------------------ */
4651 void
4652 ipf_sttab_init(softc, tqp)
4653         ipf_main_softc_t *softc;
4654         ipftq_t *tqp;
4655 {
4656         int i;
4657
4658         for (i = IPF_TCP_NSTATES - 1; i >= 0; i--) {
4659                 IPFTQ_INIT(&tqp[i], 0, "ipftq tcp tab");
4660                 tqp[i].ifq_next = tqp + i + 1;
4661         }
4662         tqp[IPF_TCP_NSTATES - 1].ifq_next = NULL;
4663         tqp[IPF_TCPS_CLOSED].ifq_ttl = softc->ipf_tcpclosed;
4664         tqp[IPF_TCPS_LISTEN].ifq_ttl = softc->ipf_tcptimeout;
4665         tqp[IPF_TCPS_SYN_SENT].ifq_ttl = softc->ipf_tcpsynsent;
4666         tqp[IPF_TCPS_SYN_RECEIVED].ifq_ttl = softc->ipf_tcpsynrecv;
4667         tqp[IPF_TCPS_ESTABLISHED].ifq_ttl = softc->ipf_tcpidletimeout;
4668         tqp[IPF_TCPS_CLOSE_WAIT].ifq_ttl = softc->ipf_tcphalfclosed;
4669         tqp[IPF_TCPS_FIN_WAIT_1].ifq_ttl = softc->ipf_tcphalfclosed;
4670         tqp[IPF_TCPS_CLOSING].ifq_ttl = softc->ipf_tcptimeout;
4671         tqp[IPF_TCPS_LAST_ACK].ifq_ttl = softc->ipf_tcplastack;
4672         tqp[IPF_TCPS_FIN_WAIT_2].ifq_ttl = softc->ipf_tcpclosewait;
4673         tqp[IPF_TCPS_TIME_WAIT].ifq_ttl = softc->ipf_tcptimewait;
4674         tqp[IPF_TCPS_HALF_ESTAB].ifq_ttl = softc->ipf_tcptimeout;
4675 }
4676
4677
4678 /* ------------------------------------------------------------------------ */
4679 /* Function:    ipf_sttab_destroy                                           */
4680 /* Returns:     Nil                                                         */
4681 /* Parameters:  tqp(I) - pointer to an array of timeout queues for TCP      */
4682 /*                                                                          */
4683 /* Do whatever is necessary to "destroy" each of the entries in the array   */
4684 /* of timeout queues for TCP.                                               */
4685 /* ------------------------------------------------------------------------ */
4686 void
4687 ipf_sttab_destroy(tqp)
4688         ipftq_t *tqp;
4689 {
4690         int i;
4691
4692         for (i = IPF_TCP_NSTATES - 1; i >= 0; i--)
4693                 MUTEX_DESTROY(&tqp[i].ifq_lock);
4694 }
4695
4696
4697 /* ------------------------------------------------------------------------ */
4698 /* Function:    ipf_state_deref                                             */
4699 /* Returns:     Nil                                                         */
4700 /* Parameters:  softc(I) - pointer to soft context main structure           */
4701 /*              isp(I) - pointer to pointer to state table entry            */
4702 /*                                                                          */
4703 /* Decrement the reference counter for this state table entry and free it   */
4704 /* if there are no more things using it.                                    */
4705 /*                                                                          */
4706 /* This function is only called when cleaning up after increasing is_ref by */
4707 /* one earlier in the 'code path' so if is_ref is 1 when entering, we do    */
4708 /* have an orphan, otherwise not.  However there is a possible race between */
4709 /* the entry being deleted via flushing with an ioctl call (that calls the  */
4710 /* delete function directly) and the tail end of packet processing so we    */
4711 /* need to grab is_lock before doing the check to synchronise the two code  */
4712 /* paths.                                                                   */
4713 /*                                                                          */
4714 /* When operating in userland (ipftest), we have no timers to clear a state */
4715 /* entry.  Therefore, we make a few simple tests before deleting an entry   */
4716 /* outright.  We compare states on each side looking for a combination of   */
4717 /* TIME_WAIT (should really be FIN_WAIT_2?) and LAST_ACK.  Then we factor   */
4718 /* in packet direction with the interface list to make sure we don't        */
4719 /* prematurely delete an entry on a final inbound packet that's we're also  */
4720 /* supposed to route elsewhere.                                             */
4721 /*                                                                          */
4722 /* Internal parameters:                                                     */
4723 /*    state[0] = state of source (host that initiated connection)           */
4724 /*    state[1] = state of dest   (host that accepted the connection)        */
4725 /*                                                                          */
4726 /*    dir == 0 : a packet from source to dest                               */
4727 /*    dir == 1 : a packet from dest to source                               */
4728 /* ------------------------------------------------------------------------ */
4729 void
4730 ipf_state_deref(softc, isp)
4731         ipf_main_softc_t *softc;
4732         ipstate_t **isp;
4733 {
4734         ipstate_t *is = *isp;
4735
4736         is = *isp;
4737         *isp = NULL;
4738
4739         MUTEX_ENTER(&is->is_lock);
4740         if (is->is_ref > 1) {
4741                 is->is_ref--;
4742                 MUTEX_EXIT(&is->is_lock);
4743 #ifndef _KERNEL
4744                 if ((is->is_sti.tqe_state[0] > IPF_TCPS_ESTABLISHED) ||
4745                     (is->is_sti.tqe_state[1] > IPF_TCPS_ESTABLISHED)) {
4746                         ipf_state_del(softc, is, ISL_EXPIRE);
4747                 }
4748 #endif
4749                 return;
4750         }
4751         MUTEX_EXIT(&is->is_lock);
4752
4753         WRITE_ENTER(&softc->ipf_state);
4754         ipf_state_del(softc, is, ISL_ORPHAN);
4755         RWLOCK_EXIT(&softc->ipf_state);
4756 }
4757
4758
4759 /* ------------------------------------------------------------------------ */
4760 /* Function:    ipf_state_setqueue                                          */
4761 /* Returns:     Nil                                                         */
4762 /* Parameters:  softc(I) - pointer to soft context main structure           */
4763 /*              is(I)    - pointer to state structure                       */
4764 /*              rev(I)   - forward(0) or reverse(1) direction               */
4765 /* Locks:       ipf_state (read or write)                                   */
4766 /*                                                                          */
4767 /* Put the state entry on its default queue entry, using rev as a helped in */
4768 /* determining which queue it should be placed on.                          */
4769 /* ------------------------------------------------------------------------ */
4770 void
4771 ipf_state_setqueue(softc, is, rev)
4772         ipf_main_softc_t *softc;
4773         ipstate_t *is;
4774         int rev;
4775 {
4776         ipf_state_softc_t *softs = softc->ipf_state_soft;
4777         ipftq_t *oifq, *nifq;
4778
4779         if ((is->is_sti.tqe_flags & TQE_RULEBASED) != 0)
4780                 nifq = is->is_tqehead[rev];
4781         else
4782                 nifq = NULL;
4783
4784         if (nifq == NULL) {
4785                 switch (is->is_p)
4786                 {
4787 #ifdef USE_INET6
4788                 case IPPROTO_ICMPV6 :
4789                         if (rev == 1)
4790                                 nifq = &softs->ipf_state_icmpacktq;
4791                         else
4792                                 nifq = &softs->ipf_state_icmptq;
4793                         break;
4794 #endif
4795                 case IPPROTO_ICMP :
4796                         if (rev == 1)
4797                                 nifq = &softs->ipf_state_icmpacktq;
4798                         else
4799                                 nifq = &softs->ipf_state_icmptq;
4800                         break;
4801                 case IPPROTO_TCP :
4802                         nifq = softs->ipf_state_tcptq + is->is_state[rev];
4803                         break;
4804
4805                 case IPPROTO_UDP :
4806                         if (rev == 1)
4807                                 nifq = &softs->ipf_state_udpacktq;
4808                         else
4809                                 nifq = &softs->ipf_state_udptq;
4810                         break;
4811
4812                 default :
4813                         nifq = &softs->ipf_state_iptq;
4814                         break;
4815                 }
4816         }
4817
4818         oifq = is->is_sti.tqe_ifq;
4819         /*
4820          * If it's currently on a timeout queue, move it from one queue to
4821          * another, else put it on the end of the newly determined queue.
4822          */
4823         if (oifq != NULL)
4824                 ipf_movequeue(softc->ipf_ticks, &is->is_sti, oifq, nifq);
4825         else
4826                 ipf_queueappend(softc->ipf_ticks, &is->is_sti, nifq, is);
4827         return;
4828 }
4829
4830
4831 /* ------------------------------------------------------------------------ */
4832 /* Function:    ipf_state_iter                                              */
4833 /* Returns:     int - 0 == success, else error                              */
4834 /* Parameters:  softc(I) - pointer to main soft context                     */
4835 /*              token(I) - pointer to ipftoken structure                    */
4836 /*              itp(I)   - pointer to ipfgeniter structure                  */
4837 /*              obj(I)   - pointer to data description structure            */
4838 /*                                                                          */
4839 /* This function handles the SIOCGENITER ioctl for the state tables and     */
4840 /* walks through the list of entries in the state table list (softs->ipf_state_list.)    */
4841 /* ------------------------------------------------------------------------ */
4842 static int
4843 ipf_state_iter(softc, token, itp, obj)
4844         ipf_main_softc_t *softc;
4845         ipftoken_t *token;
4846         ipfgeniter_t *itp;
4847         ipfobj_t *obj;
4848 {
4849         ipf_state_softc_t *softs = softc->ipf_state_soft;
4850         ipstate_t *is, *next, zero;
4851         int error;
4852
4853         if (itp->igi_data == NULL) {
4854                 IPFERROR(100026);
4855                 return EFAULT;
4856         }
4857
4858         if (itp->igi_nitems < 1) {
4859                 IPFERROR(100027);
4860                 return ENOSPC;
4861         }
4862
4863         if (itp->igi_type != IPFGENITER_STATE) {
4864                 IPFERROR(100028);
4865                 return EINVAL;
4866         }
4867
4868         is = token->ipt_data;
4869         if (is == (void *)-1) {
4870                 IPFERROR(100029);
4871                 return ESRCH;
4872         }
4873
4874         error = 0;
4875         obj->ipfo_type = IPFOBJ_IPSTATE;
4876         obj->ipfo_size = sizeof(ipstate_t);
4877
4878         READ_ENTER(&softc->ipf_state);
4879
4880         is = token->ipt_data;
4881         if (is == NULL) {
4882                 next = softs->ipf_state_list;
4883         } else {
4884                 next = is->is_next;
4885         }
4886
4887         /*
4888          * If we find a state entry to use, bump its reference count so that
4889          * it can be used for is_next when we come back.
4890          */
4891         if (next != NULL) {
4892                 MUTEX_ENTER(&next->is_lock);
4893                 next->is_ref++;
4894                 MUTEX_EXIT(&next->is_lock);
4895                 token->ipt_data = next;
4896         } else {
4897                 bzero(&zero, sizeof(zero));
4898                 next = &zero;
4899                 token->ipt_data = NULL;
4900         }
4901         if (next->is_next == NULL)
4902                 ipf_token_mark_complete(token);
4903
4904         RWLOCK_EXIT(&softc->ipf_state);
4905
4906         obj->ipfo_ptr = itp->igi_data;
4907         error = ipf_outobjk(softc, obj, next);
4908         if (is != NULL)
4909                 ipf_state_deref(softc, &is);
4910
4911         return error;
4912 }
4913
4914
4915 /* ------------------------------------------------------------------------ */
4916 /* Function:    ipf_state_gettable                                          */
4917 /* Returns:     int     - 0 = success, else error                           */
4918 /* Parameters:  softc(I) - pointer to main soft context                     */
4919 /*              softs(I) - pointer to state context structure               */
4920 /*              data(I)  - pointer to ioctl data                             */
4921 /*                                                                          */
4922 /* This function handles ioctl requests for tables of state information.    */
4923 /* At present the only table it deals with is the hash bucket statistics.   */
4924 /* ------------------------------------------------------------------------ */
4925 static int
4926 ipf_state_gettable(softc, softs, data)
4927         ipf_main_softc_t *softc;
4928         ipf_state_softc_t *softs;
4929         char *data;
4930 {
4931         ipftable_t table;
4932         int error;
4933
4934         error = ipf_inobj(softc, data, NULL, &table, IPFOBJ_GTABLE);
4935         if (error != 0)
4936                 return error;
4937
4938         if (table.ita_type != IPFTABLE_BUCKETS) {
4939                 IPFERROR(100031);
4940                 return EINVAL;
4941         }
4942
4943         error = COPYOUT(softs->ipf_state_stats.iss_bucketlen, table.ita_table,
4944                         softs->ipf_state_size * sizeof(u_int));
4945         if (error != 0) {
4946                 IPFERROR(100032);
4947                 error = EFAULT;
4948         }
4949         return error;
4950 }
4951
4952
4953 /* ------------------------------------------------------------------------ */
4954 /* Function:    ipf_state_setpending                                        */
4955 /* Returns:     Nil                                                         */
4956 /* Parameters:  softc(I) - pointer to main soft context                     */
4957 /*              is(I)    - pointer to state structure                       */
4958 /* Locks:       ipf_state (read or write)                                   */
4959 /*                                                                          */
4960 /* Put the state entry on to the pending queue - this queue has a very      */
4961 /* short lifetime where items are put that can't be deleted straight away   */
4962 /* because of locking issues but we want to delete them ASAP, anyway.       */
4963 /* ------------------------------------------------------------------------ */
4964 void
4965 ipf_state_setpending(softc, is)
4966         ipf_main_softc_t *softc;
4967         ipstate_t *is;
4968 {
4969         ipf_state_softc_t *softs = softc->ipf_state_soft;
4970         ipftq_t *oifq;
4971
4972         oifq = is->is_sti.tqe_ifq;
4973         if (oifq != NULL)
4974                 ipf_movequeue(softc->ipf_ticks, &is->is_sti, oifq,
4975                               &softs->ipf_state_pending);
4976         else
4977                 ipf_queueappend(softc->ipf_ticks, &is->is_sti,
4978                                 &softs->ipf_state_pending, is);
4979
4980         MUTEX_ENTER(&is->is_lock);
4981         if (is->is_me != NULL) {
4982                 *is->is_me = NULL;
4983                 is->is_me = NULL;
4984                 is->is_ref--;
4985         }
4986         MUTEX_EXIT(&is->is_lock);
4987 }
4988
4989
4990 /* ------------------------------------------------------------------------ */
4991 /* Function:    ipf_state_matchflush                                        */
4992 /* Returns:     Nil                                                         */
4993 /* Parameters:  softc(I) - pointer to main soft context                     */
4994 /*              data(I)  - pointer to state structure                       */
4995 /* Locks:       ipf_state (read or write)                                   */
4996 /*                                                                          */
4997 /* Flush all entries from the list of state entries that match the          */
4998 /* properties in the array loaded.                                          */
4999 /* ------------------------------------------------------------------------ */
5000 int
5001 ipf_state_matchflush(softc, data)
5002         ipf_main_softc_t *softc;
5003         caddr_t data;
5004 {
5005         ipf_state_softc_t *softs = softc->ipf_state_soft;
5006         int *array, flushed, error;
5007         ipstate_t *state, *statenext;
5008         ipfobj_t obj;
5009
5010         error = ipf_matcharray_load(softc, data, &obj, &array);
5011         if (error != 0)
5012                 return error;
5013
5014         flushed = 0;
5015
5016         for (state = softs->ipf_state_list; state != NULL; state = statenext) {
5017                 statenext = state->is_next;
5018                 if (ipf_state_matcharray(state, array, softc->ipf_ticks) == 0) {
5019                         ipf_state_del(softc, state, ISL_FLUSH);
5020                         flushed++;
5021                 }
5022         }
5023
5024         obj.ipfo_retval = flushed;
5025         error = BCOPYOUT(&obj, data, sizeof(obj));
5026
5027         KFREES(array, array[0] * sizeof(*array));
5028
5029         return error;
5030 }
5031
5032
5033 /* ------------------------------------------------------------------------ */
5034 /* Function:    ipf_state_matcharray                                        */
5035 /* Returns:     int   - 0 = no match, 1 = match                             */
5036 /* Parameters:  state(I) - pointer to state structure                       */
5037 /*              array(I) - pointer to ipf matching expression               */
5038 /*              ticks(I) - current value of ipfilter tick timer             */
5039 /* Locks:       ipf_state (read or write)                                   */
5040 /*                                                                          */
5041 /* Compare a state entry with the match array passed in and return a value  */
5042 /* to indicate whether or not the matching was successful.                  */
5043 /* ------------------------------------------------------------------------ */
5044 static int
5045 ipf_state_matcharray(state, array, ticks)
5046         ipstate_t *state;
5047         int *array;
5048         u_long ticks;
5049 {
5050         int i, n, *x, rv, p;
5051         ipfexp_t *e;
5052
5053         rv = 0;
5054         n = array[0];
5055         x = array + 1;
5056
5057         for (; n > 0; x += 3 + x[3], rv = 0) {
5058                 e = (ipfexp_t *)x;
5059                 n -= e->ipfe_size;
5060                 if (x[0] == IPF_EXP_END)
5061                         break;
5062
5063                 /*
5064                  * If we need to match the protocol and that doesn't match,
5065                  * don't even both with the instruction array.
5066                  */
5067                 p = e->ipfe_cmd >> 16;
5068                 if ((p != 0) && (p != state->is_p))
5069                         break;
5070
5071                 switch (e->ipfe_cmd)
5072                 {
5073                 case IPF_EXP_IP_PR :
5074                         for (i = 0; !rv && i < e->ipfe_narg; i++) {
5075                                 rv |= (state->is_p == e->ipfe_arg0[i]);
5076                         }
5077                         break;
5078
5079                 case IPF_EXP_IP_SRCADDR :
5080                         if (state->is_v != 4)
5081                                 break;
5082                         for (i = 0; !rv && i < e->ipfe_narg; i++) {
5083                                 rv |= ((state->is_saddr &
5084                                         e->ipfe_arg0[i * 2 + 1]) ==
5085                                       e->ipfe_arg0[i * 2]);
5086                         }
5087                         break;
5088
5089                 case IPF_EXP_IP_DSTADDR :
5090                         if (state->is_v != 4)
5091                                 break;
5092                         for (i = 0; !rv && i < e->ipfe_narg; i++) {
5093                                 rv |= ((state->is_daddr &
5094                                         e->ipfe_arg0[i * 2 + 1]) ==
5095                                        e->ipfe_arg0[i * 2]);
5096                         }
5097                         break;
5098
5099                 case IPF_EXP_IP_ADDR :
5100                         if (state->is_v != 4)
5101                                 break;
5102                         for (i = 0; !rv && i < e->ipfe_narg; i++) {
5103                                 rv |= ((state->is_saddr &
5104                                         e->ipfe_arg0[i * 2 + 1]) ==
5105                                        e->ipfe_arg0[i * 2]) ||
5106                                        ((state->is_daddr &
5107                                         e->ipfe_arg0[i * 2 + 1]) ==
5108                                        e->ipfe_arg0[i * 2]);
5109                         }
5110                         break;
5111
5112 #ifdef USE_INET6
5113                 case IPF_EXP_IP6_SRCADDR :
5114                         if (state->is_v != 6)
5115                                 break;
5116                         for (i = 0; !rv && i < x[3]; i++) {
5117                                 rv |= IP6_MASKEQ(&state->is_src.in6,
5118                                                  &e->ipfe_arg0[i * 8 + 4],
5119                                                  &e->ipfe_arg0[i * 8]);
5120                         }
5121                         break;
5122
5123                 case IPF_EXP_IP6_DSTADDR :
5124                         if (state->is_v != 6)
5125                                 break;
5126                         for (i = 0; !rv && i < x[3]; i++) {
5127                                 rv |= IP6_MASKEQ(&state->is_dst.in6,
5128                                                  &e->ipfe_arg0[i * 8 + 4],
5129                                                  &e->ipfe_arg0[i * 8]);
5130                         }
5131                         break;
5132
5133                 case IPF_EXP_IP6_ADDR :
5134                         if (state->is_v != 6)
5135                                 break;
5136                         for (i = 0; !rv && i < x[3]; i++) {
5137                                 rv |= IP6_MASKEQ(&state->is_src.in6,
5138                                                  &e->ipfe_arg0[i * 8 + 4],
5139                                                  &e->ipfe_arg0[i * 8]) ||
5140                                       IP6_MASKEQ(&state->is_dst.in6,
5141                                                  &e->ipfe_arg0[i * 8 + 4],
5142                                                  &e->ipfe_arg0[i * 8]);
5143                         }
5144                         break;
5145 #endif
5146
5147                 case IPF_EXP_UDP_PORT :
5148                 case IPF_EXP_TCP_PORT :
5149                         for (i = 0; !rv && i < e->ipfe_narg; i++) {
5150                                 rv |= (state->is_sport == e->ipfe_arg0[i]) ||
5151                                       (state->is_dport == e->ipfe_arg0[i]);
5152                         }
5153                         break;
5154
5155                 case IPF_EXP_UDP_SPORT :
5156                 case IPF_EXP_TCP_SPORT :
5157                         for (i = 0; !rv && i < e->ipfe_narg; i++) {
5158                                 rv |= (state->is_sport == e->ipfe_arg0[i]);
5159                         }
5160                         break;
5161
5162                 case IPF_EXP_UDP_DPORT :
5163                 case IPF_EXP_TCP_DPORT :
5164                         for (i = 0; !rv && i < e->ipfe_narg; i++) {
5165                                 rv |= (state->is_dport == e->ipfe_arg0[i]);
5166                         }
5167                         break;
5168
5169                 case IPF_EXP_TCP_STATE :
5170                         for (i = 0; !rv && i < e->ipfe_narg; i++) {
5171                                 rv |= (state->is_state[0] == e->ipfe_arg0[i]) ||
5172                                       (state->is_state[1] == e->ipfe_arg0[i]);
5173                         }
5174                         break;
5175
5176                 case IPF_EXP_IDLE_GT :
5177                         rv |= (ticks - state->is_touched > e->ipfe_arg0[0]);
5178                         break;
5179                 }
5180
5181                 /*
5182                  * Factor in doing a negative match.
5183                  */
5184                 rv ^= e->ipfe_not;
5185
5186                 if (rv == 0)
5187                         break;
5188         }
5189
5190         return rv;
5191 }
5192
5193
5194 /* ------------------------------------------------------------------------ */
5195 /* Function:    ipf_state_settimeout                                        */
5196 /* Returns:     int 0 = success, else failure                               */
5197 /* Parameters:  softc(I)  - pointer to main soft context                    */
5198 /*              t(I)      - pointer to tuneable being changed               */
5199 /*              p(I)      - pointer to the new value                        */
5200 /*                                                                          */
5201 /* Sets a timeout value for one of the many timeout queues.  We find the    */
5202 /* correct queue using a somewhat manual process of comparing the timeout   */
5203 /* names for each specific value available and calling ipf_apply_timeout on */
5204 /* that queue so that all of the items on it are updated accordingly.       */
5205 /* ------------------------------------------------------------------------ */
5206 int
5207 ipf_state_settimeout(softc, t, p)
5208         struct ipf_main_softc_s *softc;
5209         ipftuneable_t *t;
5210         ipftuneval_t *p;
5211 {
5212         ipf_state_softc_t *softs = softc->ipf_state_soft;
5213
5214         /*
5215          * In case there is nothing to do...
5216          */
5217         if (*t->ipft_pint == p->ipftu_int)
5218                 return 0;
5219
5220         if (!strncmp(t->ipft_name, "tcp_", 4))
5221                 return ipf_settimeout_tcp(t, p, softs->ipf_state_tcptq);
5222
5223         if (!strcmp(t->ipft_name, "udp_timeout")) {
5224                 ipf_apply_timeout(&softs->ipf_state_udptq, p->ipftu_int);
5225         } else if (!strcmp(t->ipft_name, "udp_ack_timeout")) {
5226                 ipf_apply_timeout(&softs->ipf_state_udpacktq, p->ipftu_int);
5227         } else if (!strcmp(t->ipft_name, "icmp_timeout")) {
5228                 ipf_apply_timeout(&softs->ipf_state_icmptq, p->ipftu_int);
5229         } else if (!strcmp(t->ipft_name, "icmp_ack_timeout")) {
5230                 ipf_apply_timeout(&softs->ipf_state_icmpacktq, p->ipftu_int);
5231         } else if (!strcmp(t->ipft_name, "ip_timeout")) {
5232                 ipf_apply_timeout(&softs->ipf_state_iptq, p->ipftu_int);
5233         } else {
5234                 IPFERROR(100034);
5235                 return ESRCH;
5236         }
5237
5238         /*
5239          * Update the tuneable being set.
5240          */
5241         *t->ipft_pint = p->ipftu_int;
5242
5243         return 0;
5244 }
5245
5246
5247 /* ------------------------------------------------------------------------ */
5248 /* Function:    ipf_state_rehash                                            */
5249 /* Returns:     int 0 = success, else failure                               */
5250 /* Parameters:  softc(I)  - pointer to main soft context                    */
5251 /*              t(I)      - pointer to tuneable being changed               */
5252 /*              p(I)      - pointer to the new value                        */
5253 /*                                                                          */
5254 /* To change the size of the state hash table at runtime, a new table has   */
5255 /* to be allocated and then all of the existing entries put in it, bumping  */
5256 /* up the bucketlength for it as we go along.                               */
5257 /* ------------------------------------------------------------------------ */
5258 int
5259 ipf_state_rehash(softc, t, p)
5260         ipf_main_softc_t *softc;
5261         ipftuneable_t *t;
5262         ipftuneval_t *p;
5263 {
5264         ipf_state_softc_t *softs = softc->ipf_state_soft;
5265         ipstate_t **newtab, *is;
5266         u_long *newseed;
5267         u_int *bucketlens;
5268         u_int maxbucket;
5269         u_int newsize;
5270         u_int hv;
5271         int i;
5272
5273         newsize = p->ipftu_int;
5274         /*
5275          * In case there is nothing to do...
5276          */
5277         if (newsize == softs->ipf_state_size)
5278                 return 0;
5279
5280         KMALLOCS(newtab, ipstate_t **, newsize * sizeof(ipstate_t *));
5281         if (newtab == NULL) {
5282                 IPFERROR(100035);
5283                 return ENOMEM;
5284         }
5285
5286         KMALLOCS(bucketlens, u_int *, newsize * sizeof(u_int));
5287         if (bucketlens == NULL) {
5288                 KFREES(newtab, newsize * sizeof(*softs->ipf_state_table));
5289                 IPFERROR(100036);
5290                 return ENOMEM;
5291         }
5292
5293         newseed = ipf_state_seed_alloc(newsize, softs->ipf_state_max);
5294         if (newseed == NULL) {
5295                 KFREES(bucketlens, newsize * sizeof(*bucketlens));
5296                 KFREES(newtab, newsize * sizeof(*newtab));
5297                 IPFERROR(100037);
5298                 return ENOMEM;
5299         }
5300
5301         for (maxbucket = 0, i = newsize; i > 0; i >>= 1)
5302                 maxbucket++;
5303         maxbucket *= 2;
5304
5305         bzero((char *)newtab, newsize * sizeof(ipstate_t *));
5306         bzero((char *)bucketlens, newsize * sizeof(u_int));
5307
5308         WRITE_ENTER(&softc->ipf_state);
5309
5310         if (softs->ipf_state_table != NULL) {
5311                 KFREES(softs->ipf_state_table,
5312                        softs->ipf_state_size * sizeof(*softs->ipf_state_table));
5313         }
5314         softs->ipf_state_table = newtab;
5315
5316         if (softs->ipf_state_seed != NULL) {
5317                 KFREES(softs->ipf_state_seed,
5318                        softs->ipf_state_size * sizeof(*softs->ipf_state_seed));
5319         }
5320         softs->ipf_state_seed = newseed;
5321
5322         if (softs->ipf_state_stats.iss_bucketlen != NULL) {
5323                 KFREES(softs->ipf_state_stats.iss_bucketlen,
5324                        softs->ipf_state_size * sizeof(u_int));
5325         }
5326         softs->ipf_state_stats.iss_bucketlen = bucketlens;
5327         softs->ipf_state_maxbucket = maxbucket;
5328         softs->ipf_state_size = newsize;
5329
5330         /*
5331          * Walk through the entire list of state table entries and put them
5332          * in the new state table, somewhere.  Because we have a new table,
5333          * we need to restart the counter of how many chains are in use.
5334          */
5335         softs->ipf_state_stats.iss_inuse = 0;
5336         for (is = softs->ipf_state_list; is != NULL; is = is->is_next) {
5337                 is->is_hnext = NULL;
5338                 is->is_phnext = NULL;
5339                 hv = is->is_hv % softs->ipf_state_size;
5340
5341                 if (softs->ipf_state_table[hv] != NULL)
5342                         softs->ipf_state_table[hv]->is_phnext = &is->is_hnext;
5343                 else
5344                         softs->ipf_state_stats.iss_inuse++;
5345                 is->is_phnext = softs->ipf_state_table + hv;
5346                 is->is_hnext = softs->ipf_state_table[hv];
5347                 softs->ipf_state_table[hv] = is;
5348                 softs->ipf_state_stats.iss_bucketlen[hv]++;
5349         }
5350         RWLOCK_EXIT(&softc->ipf_state);
5351
5352         return 0;
5353 }
5354
5355
5356 /* ------------------------------------------------------------------------ */
5357 /* Function:    ipf_state_add_tq                                            */
5358 /* Returns:     ipftq_t * - NULL = failure, else pointer to new timeout     */
5359 /*                          queue                                           */
5360 /* Parameters:  softc(I)  - pointer to main soft context                    */
5361 /*              ttl(I)    - pointer to the ttl for the new queue            */
5362 /*                                                                          */
5363 /* Request a pointer to a timeout queue that has a ttl as given by the      */
5364 /* value being passed in.  The timeout queue is added tot the list of those */
5365 /* used internally for stateful filtering.                                  */
5366 /* ------------------------------------------------------------------------ */
5367 ipftq_t *
5368 ipf_state_add_tq(softc, ttl)
5369         ipf_main_softc_t *softc;
5370         int ttl;
5371 {
5372         ipf_state_softc_t *softs = softc->ipf_state_soft;
5373
5374         return ipf_addtimeoutqueue(softc, &softs->ipf_state_usertq, ttl);
5375 }
5376
5377
5378 #ifndef _KERNEL
5379 /*
5380  * Display the built up state table rules and mapping entries.
5381  */
5382 void
5383 ipf_state_dump(softc, arg)
5384         ipf_main_softc_t *softc;
5385         void *arg;
5386 {
5387         ipf_state_softc_t *softs = arg;
5388         ipstate_t *ips;
5389
5390         printf("List of active state sessions:\n");
5391         for (ips = softs->ipf_state_list; ips != NULL; )
5392                 ips = printstate(ips, opts & (OPT_DEBUG|OPT_VERBOSE),
5393                                  softc->ipf_ticks);
5394 }
5395 #endif