sys/contrib/ipfilter/netinet/ip_proxy.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 #if defined(KERNEL) || defined(_KERNEL)
   9 # undef KERNEL
  10 # undef _KERNEL
  11 # define        KERNEL  1
  12 # define        _KERNEL 1
  13 #endif
  14 #include <sys/errno.h>
  15 #include <sys/types.h>
  16 #include <sys/param.h>
  17 #include <sys/time.h>
  18 #include <sys/file.h>
  19 #if !defined(AIX)
  20 # include <sys/fcntl.h>
  21 #endif
  22 #if !defined(_KERNEL) && !defined(__KERNEL__)
  23 # include <stdio.h>
  24 # include <string.h>
  25 # include <stdlib.h>
  26 # include <ctype.h>
  27 # define _KERNEL
  28 # ifdef __OpenBSD__
  29 struct file;
  30 # endif
  31 # include <sys/uio.h>
  32 # undef _KERNEL
  33 #endif
  34 #if !defined(linux)
  35 # include <sys/protosw.h>
  36 #endif
  37 #include <sys/socket.h>
  38 #if defined(_KERNEL)
  39 # if !defined(__NetBSD__) && !defined(sun) && !defined(__osf__) && \
  40      !defined(__OpenBSD__) && !defined(__hpux) && !defined(__sgi) && \
  41      !defined(AIX)
  42 #  include <sys/ctype.h>
  43 # endif
  44 # include <sys/systm.h>
  45 # if !defined(__SVR4) && !defined(__svr4__)
  46 #  include <sys/mbuf.h>
  47 # endif
  48 #endif
  49 #if defined(_KERNEL) && (__FreeBSD_version >= 220000)
  50 # include <sys/filio.h>
  51 # include <sys/fcntl.h>
  52 #else
  53 # include <sys/ioctl.h>
  54 #endif
  55 #if defined(__SVR4) || defined(__svr4__)
  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 #if __FreeBSD_version >= 300000
  64 # include <sys/queue.h>
  65 #endif
  66 #include <net/if.h>
  67 #ifdef sun
  68 # include <net/af.h>
  69 #endif
  70 #include <netinet/in.h>
  71 #include <netinet/in_systm.h>
  72 #include <netinet/ip.h>
  73 #ifndef linux
  74 # include <netinet/ip_var.h>
  75 #endif
  76 #include <netinet/tcp.h>
  77 #include <netinet/udp.h>
  78 #include <netinet/ip_icmp.h>
  79 #include "netinet/ip_compat.h"
  80 #include <netinet/tcpip.h>
  81 #include "netinet/ip_fil.h"
  82 #include "netinet/ip_nat.h"
  83 #include "netinet/ip_state.h"
  84 #include "netinet/ip_proxy.h"
  85 #if (__FreeBSD_version >= 300000)
  86 # include <sys/malloc.h>
  87 #endif
  88
  89 /* END OF INCLUDES */
  90
  91 #include "netinet/ip_ftp_pxy.c"
  92 #include "netinet/ip_tftp_pxy.c"
  93 #include "netinet/ip_rcmd_pxy.c"
  94 #include "netinet/ip_pptp_pxy.c"
  95 #if defined(_KERNEL)
  96 # include "netinet/ip_irc_pxy.c"
  97 # include "netinet/ip_raudio_pxy.c"
  98 # include "netinet/ip_netbios_pxy.c"
  99 #endif
 100 #include "netinet/ip_ipsec_pxy.c"
 101 #include "netinet/ip_rpcb_pxy.c"
 102
 103 #if !defined(lint)
 104 static const char rcsid[] = "@(#)$Id$";
 105 #endif
 106
 107 #define AP_SESS_SIZE    53
 108
 109 static int ipf_proxy_fixseqack __P((fr_info_t *, ip_t *, ap_session_t *, int ));
 110 static aproxy_t *ipf_proxy_create_clone __P((ipf_main_softc_t *, aproxy_t *));
 111
 112 typedef struct ipf_proxy_softc_s {
 113         int             ips_proxy_debug;
 114         int             ips_proxy_session_size;
 115         ap_session_t    **ips_sess_tab;
 116         ap_session_t    *ips_sess_list;
 117         aproxy_t        *ips_proxies;
 118         int             ips_init_run;
 119         ipftuneable_t   *ipf_proxy_tune;
 120 } ipf_proxy_softc_t;
 121
 122 static ipftuneable_t ipf_proxy_tuneables[] = {
 123         { { (void *)offsetof(ipf_proxy_softc_t, ips_proxy_debug) },
 124                 "proxy_debug",  0,      0x1f,
 125                 stsizeof(ipf_proxy_softc_t, ips_proxy_debug),
 126                 0,      NULL,   NULL },
 127         { { NULL },             NULL,                   0,      0,
 128                 0,
 129                 0,      NULL,   NULL}
 130 };
 131
 132 static  aproxy_t        *ap_proxylist = NULL;
 133 static  aproxy_t        ips_proxies[] = {
 134 #ifdef  IPF_FTP_PROXY
 135         { NULL, NULL, "ftp", (char)IPPROTO_TCP, 0, 0, 0,
 136           ipf_p_ftp_main_load, ipf_p_ftp_main_unload,
 137           ipf_p_ftp_soft_create, ipf_p_ftp_soft_destroy,
 138           NULL, NULL,
 139           ipf_p_ftp_new, ipf_p_ftp_del, ipf_p_ftp_in, ipf_p_ftp_out, NULL,
 140           NULL, NULL, NULL, NULL },
 141 #endif
 142 #ifdef  IPF_TFTP_PROXY
 143         { NULL, NULL, "tftp", (char)IPPROTO_UDP, 0, 0, 0,
 144           ipf_p_tftp_main_load, ipf_p_tftp_main_unload,
 145           ipf_p_tftp_soft_create, ipf_p_tftp_soft_destroy,
 146           NULL, NULL,
 147           ipf_p_tftp_new, ipf_p_tftp_del,
 148           ipf_p_tftp_in, ipf_p_tftp_out, NULL,
 149           NULL, NULL, NULL, NULL },
 150 #endif
 151 #ifdef  IPF_IRC_PROXY
 152         { NULL, NULL, "irc", (char)IPPROTO_TCP, 0, 0, 0,
 153           ipf_p_irc_main_load, ipf_p_irc_main_unload,
 154           NULL, NULL,
 155           NULL, NULL,
 156           ipf_p_irc_new, NULL, NULL, ipf_p_irc_out, NULL,
 157           NULL, NULL, NULL, NULL },
 158 #endif
 159 #ifdef  IPF_RCMD_PROXY
 160         { NULL, NULL, "rcmd", (char)IPPROTO_TCP, 0, 0, 0,
 161           ipf_p_rcmd_main_load, ipf_p_rcmd_main_unload,
 162           NULL, NULL,
 163           NULL, NULL,
 164           ipf_p_rcmd_new, ipf_p_rcmd_del,
 165           ipf_p_rcmd_in, ipf_p_rcmd_out, NULL,
 166           NULL, NULL, NULL, NULL },
 167 #endif
 168 #ifdef  IPF_RAUDIO_PROXY
 169         { NULL, NULL, "raudio", (char)IPPROTO_TCP, 0, 0, 0,
 170           ipf_p_raudio_main_load, ipf_p_raudio_main_unload,
 171           NULL, NULL,
 172           NULL, NULL,
 173           ipf_p_raudio_new, NULL, ipf_p_raudio_in, ipf_p_raudio_out, NULL,
 174           NULL, NULL, NULL, NULL },
 175 #endif
 176 #ifdef  IPF_MSNRPC_PROXY
 177         { NULL, NULL, "msnrpc", (char)IPPROTO_TCP, 0, 0, 0,
 178           ipf_p_msnrpc_init, ipf_p_msnrpc_fini,
 179           NULL, NULL,
 180           NULL, NULL,
 181           ipf_p_msnrpc_new, NULL, ipf_p_msnrpc_in, ipf_p_msnrpc_out, NULL,
 182           NULL, NULL, NULL, NULL },
 183 #endif
 184 #ifdef  IPF_NETBIOS_PROXY
 185         { NULL, NULL, "netbios", (char)IPPROTO_UDP, 0, 0, 0,
 186           ipf_p_netbios_main_load, ipf_p_netbios_main_unload,
 187           NULL, NULL,
 188           NULL, NULL,
 189           NULL, NULL, NULL, ipf_p_netbios_out, NULL,
 190           NULL, NULL, NULL, NULL },
 191 #endif
 192 #ifdef  IPF_IPSEC_PROXY
 193         { NULL, NULL, "ipsec", (char)IPPROTO_UDP, 0, 0, 0,
 194           NULL, NULL,
 195           ipf_p_ipsec_soft_create, ipf_p_ipsec_soft_destroy,
 196           ipf_p_ipsec_soft_init, ipf_p_ipsec_soft_fini,
 197           ipf_p_ipsec_new, ipf_p_ipsec_del,
 198           ipf_p_ipsec_inout, ipf_p_ipsec_inout, ipf_p_ipsec_match,
 199           NULL, NULL, NULL, NULL },
 200 #endif
 201 #ifdef  IPF_DNS_PROXY
 202         { NULL, NULL, "dns", (char)IPPROTO_UDP, 0, 0, 0,
 203           NULL, NULL,
 204           ipf_p_dns_soft_create, ipf_p_dns_soft_destroy,
 205           NULL, NULL,
 206           ipf_p_dns_new, ipf_p_ipsec_del,
 207           ipf_p_dns_inout, ipf_p_dns_inout, ipf_p_dns_match,
 208           ipf_p_dns_ctl, NULL, NULL, NULL },
 209 #endif
 210 #ifdef  IPF_PPTP_PROXY
 211         { NULL, NULL, "pptp", (char)IPPROTO_TCP, 0, 0, 0,
 212           ipf_p_pptp_main_load, ipf_p_pptp_main_unload,
 213           NULL, NULL,
 214           NULL, NULL,
 215           ipf_p_pptp_new, ipf_p_pptp_del,
 216           ipf_p_pptp_inout, ipf_p_pptp_inout, NULL,
 217           NULL, NULL, NULL, NULL },
 218 #endif
 219 #ifdef  IPF_RPCB_PROXY
 220 # ifndef _KERNEL
 221         { NULL, NULL, "rpcbt", (char)IPPROTO_TCP, 0, 0, 0,
 222           NULL, NULL,
 223           NULL, NULL,
 224           NULL, NULL,
 225           ipf_p_rpcb_new, ipf_p_rpcb_del,
 226           ipf_p_rpcb_in, ipf_p_rpcb_out, NULL,
 227           NULL, NULL, NULL, NULL },
 228 # endif
 229         { NULL, NULL, "rpcbu", (char)IPPROTO_UDP, 0, 0, 0,
 230           ipf_p_rpcb_main_load, ipf_p_rpcb_main_unload,
 231           NULL, NULL,
 232           NULL, NULL,
 233           ipf_p_rpcb_new, ipf_p_rpcb_del,
 234           ipf_p_rpcb_in, ipf_p_rpcb_out, NULL,
 235           NULL, NULL, NULL, NULL },
 236 #endif
 237         { NULL, NULL, "", '\0', 0, 0, 0,
 238           NULL, NULL,
 239           NULL, NULL,
 240           NULL, NULL,
 241           NULL, NULL,
 242           NULL, NULL, NULL,
 243           NULL, NULL, NULL, NULL }
 244 };
 245
 246
 247 /* ------------------------------------------------------------------------ */
 248 /* Function:    ipf_proxy_main_load                                         */
 249 /* Returns:     int    - 0 == success, else failure.                        */
 250 /* Parameters:  Nil                                                         */
 251 /*                                                                          */
 252 /* Initialise hook for kernel application proxies.                          */
 253 /* Call the initialise routine for all the compiled in kernel proxies.      */
 254 /* ------------------------------------------------------------------------ */
 255 int
 256 ipf_proxy_main_load()
 257 {
 258         aproxy_t *ap;
 259
 260         for (ap = ips_proxies; ap->apr_p; ap++) {
 261                 if (ap->apr_load != NULL)
 262                         (*ap->apr_load)();
 263         }
 264         return 0;
 265 }
 266
 267
 268 /* ------------------------------------------------------------------------ */
 269 /* Function:    ipf_proxy_main_unload                                       */
 270 /* Returns:     int - 0 == success, else failure.                           */
 271 /* Parameters:  Nil                                                         */
 272 /*                                                                          */
 273 /* Unload hook for kernel application proxies.                              */
 274 /* Call the finialise routine for all the compiled in kernel proxies.       */
 275 /* ------------------------------------------------------------------------ */
 276 int
 277 ipf_proxy_main_unload()
 278 {
 279         aproxy_t *ap;
 280
 281         for (ap = ips_proxies; ap->apr_p; ap++)
 282                 if (ap->apr_unload != NULL)
 283                         (*ap->apr_unload)();
 284         for (ap = ap_proxylist; ap; ap = ap->apr_next)
 285                 if (ap->apr_unload != NULL)
 286                         (*ap->apr_unload)();
 287
 288         return 0;
 289 }
 290
 291
 292 /* ------------------------------------------------------------------------ */
 293 /* Function:    ipf_proxy_soft_create                                       */
 294 /* Returns:     void *   -                                                  */
 295 /* Parameters:  softc(I) - pointer to soft context main structure           */
 296 /*                                                                          */
 297 /* Build the structure to hold all of the run time data to support proxies. */
 298 /* ------------------------------------------------------------------------ */
 299 void *
 300 ipf_proxy_soft_create(softc)
 301         ipf_main_softc_t *softc;
 302 {
 303         ipf_proxy_softc_t *softp;
 304         aproxy_t *last;
 305         aproxy_t *apn;
 306         aproxy_t *ap;
 307
 308         KMALLOC(softp, ipf_proxy_softc_t *);
 309         if (softp == NULL)
 310                 return softp;
 311
 312         bzero((char *)softp, sizeof(*softp));
 313
 314 #if defined(_KERNEL)
 315         softp->ips_proxy_debug = 0;
 316 #else
 317         softp->ips_proxy_debug = 2;
 318 #endif
 319         softp->ips_proxy_session_size = AP_SESS_SIZE;
 320
 321         softp->ipf_proxy_tune = ipf_tune_array_copy(softp,
 322                                                     sizeof(ipf_proxy_tuneables),
 323                                                     ipf_proxy_tuneables);
 324         if (softp->ipf_proxy_tune == NULL) {
 325                 ipf_proxy_soft_destroy(softc, softp);
 326                 return NULL;
 327         }
 328         if (ipf_tune_array_link(softc, softp->ipf_proxy_tune) == -1) {
 329                 ipf_proxy_soft_destroy(softc, softp);
 330                 return NULL;
 331         }
 332
 333         last = NULL;
 334         for (ap = ips_proxies; ap->apr_p; ap++) {
 335                 apn = ipf_proxy_create_clone(softc, ap);
 336                 if (apn == NULL)
 337                         goto failed;
 338                 if (last != NULL)
 339                         last->apr_next = apn;
 340                 else
 341                         softp->ips_proxies = apn;
 342                 last = apn;
 343         }
 344         for (ap = ips_proxies; ap != NULL; ap = ap->apr_next) {
 345                 apn = ipf_proxy_create_clone(softc, ap);
 346                 if (apn == NULL)
 347                         goto failed;
 348                 if (last != NULL)
 349                         last->apr_next = apn;
 350                 else
 351                         softp->ips_proxies = apn;
 352                 last = apn;
 353         }
 354
 355         return softp;
 356 failed:
 357         ipf_proxy_soft_destroy(softc, softp);
 358         return NULL;
 359 }
 360
 361
 362 /* ------------------------------------------------------------------------ */
 363 /* Function:    ipf_proxy_soft_create                                       */
 364 /* Returns:     void *   -                                                  */
 365 /* Parameters:  softc(I) - pointer to soft context main structure           */
 366 /*              orig(I)  - pointer to proxy definition to copy              */
 367 /*                                                                          */
 368 /* This function clones a proxy definition given by orig and returns a      */
 369 /* a pointer to that copy.                                                  */
 370 /* ------------------------------------------------------------------------ */
 371 static aproxy_t *
 372 ipf_proxy_create_clone(softc, orig)
 373         ipf_main_softc_t *softc;
 374         aproxy_t *orig;
 375 {
 376         aproxy_t *apn;
 377
 378         KMALLOC(apn, aproxy_t *);
 379         if (apn == NULL)
 380                 return NULL;
 381
 382         bcopy((char *)orig, (char *)apn, sizeof(*apn));
 383         apn->apr_next = NULL;
 384         apn->apr_soft = NULL;
 385
 386         if (apn->apr_create != NULL) {
 387                 apn->apr_soft = (*apn->apr_create)(softc);
 388                 if (apn->apr_soft == NULL) {
 389                         KFREE(apn);
 390                         return NULL;
 391                 }
 392         }
 393
 394         apn->apr_parent = orig;
 395         orig->apr_clones++;
 396
 397         return apn;
 398 }
 399
 400
 401 /* ------------------------------------------------------------------------ */
 402 /* Function:    ipf_proxy_soft_create                                       */
 403 /* Returns:     int      - 0 == success, else failure.                      */
 404 /* Parameters:  softc(I) - pointer to soft context main structure           */
 405 /*              arg(I)   - pointer to proxy contect data                    */
 406 /*                                                                          */
 407 /* Initialise the proxy context and walk through each of the proxies and    */
 408 /* call its initialisation function. This allows for proxies to do any      */
 409 /* local setup prior to actual use.                                         */
 410 /* ------------------------------------------------------------------------ */
 411 int
 412 ipf_proxy_soft_init(softc, arg)
 413         ipf_main_softc_t *softc;
 414         void *arg;
 415 {
 416         ipf_proxy_softc_t *softp;
 417         aproxy_t *ap;
 418         u_int size;
 419         int err;
 420
 421         softp = arg;
 422         size = softp->ips_proxy_session_size * sizeof(ap_session_t *);
 423
 424         KMALLOCS(softp->ips_sess_tab, ap_session_t **, size);
 425
 426         if (softp->ips_sess_tab == NULL)
 427                 return -1;
 428
 429         bzero(softp->ips_sess_tab, size);
 430
 431         for (ap = softp->ips_proxies; ap != NULL; ap = ap->apr_next) {
 432                 if (ap->apr_init != NULL) {
 433                         err = (*ap->apr_init)(softc, ap->apr_soft);
 434                         if (err != 0)
 435                                 return -2;
 436                 }
 437         }
 438         softp->ips_init_run = 1;
 439
 440         return 0;
 441 }
 442
 443
 444 /* ------------------------------------------------------------------------ */
 445 /* Function:    ipf_proxy_soft_create                                       */
 446 /* Returns:     int      - 0 == success, else failure.                      */
 447 /* Parameters:  softc(I) - pointer to soft context main structure           */
 448 /*              arg(I)   - pointer to proxy contect data                    */
 449 /*                                                                          */
 450 /* This function should always succeed. It is responsible for ensuring that */
 451 /* the proxy context can be safely called when ipf_proxy_soft_destroy is    */
 452 /* called and suring all of the proxies have similarly been instructed.     */
 453 /* ------------------------------------------------------------------------ */
 454 int
 455 ipf_proxy_soft_fini(softc, arg)
 456         ipf_main_softc_t *softc;
 457         void *arg;
 458 {
 459         ipf_proxy_softc_t *softp = arg;
 460         aproxy_t *ap;
 461
 462         for (ap = softp->ips_proxies; ap != NULL; ap = ap->apr_next) {
 463                 if (ap->apr_fini != NULL) {
 464                         (*ap->apr_fini)(softc, ap->apr_soft);
 465                 }
 466         }
 467
 468         if (softp->ips_sess_tab != NULL) {
 469                 KFREES(softp->ips_sess_tab,
 470                        softp->ips_proxy_session_size * sizeof(ap_session_t *));
 471                 softp->ips_sess_tab = NULL;
 472         }
 473         softp->ips_init_run = 0;
 474
 475         return 0;
 476 }
 477
 478
 479 /* ------------------------------------------------------------------------ */
 480 /* Function:    ipf_proxy_soft_destroy                                      */
 481 /* Returns:     Nil                                                         */
 482 /* Parameters:  softc(I) - pointer to soft context main structure           */
 483 /*              arg(I)   - pointer to proxy contect data                    */
 484 /*                                                                          */
 485 /* Free up all of the local data structures allocated during creation.      */
 486 /* ------------------------------------------------------------------------ */
 487 void
 488 ipf_proxy_soft_destroy(softc, arg)
 489         ipf_main_softc_t *softc;
 490         void *arg;
 491 {
 492         ipf_proxy_softc_t *softp = arg;
 493         aproxy_t *ap;
 494
 495         while ((ap = softp->ips_proxies) != NULL) {
 496                 softp->ips_proxies = ap->apr_next;
 497                 if (ap->apr_destroy != NULL)
 498                         (*ap->apr_destroy)(softc, ap->apr_soft);
 499                 ap->apr_parent->apr_clones--;
 500                 KFREE(ap);
 501         }
 502
 503         if (softp->ipf_proxy_tune != NULL) {
 504                 ipf_tune_array_unlink(softc, softp->ipf_proxy_tune);
 505                 KFREES(softp->ipf_proxy_tune, sizeof(ipf_proxy_tuneables));
 506                 softp->ipf_proxy_tune = NULL;
 507         }
 508
 509         KFREE(softp);
 510 }
 511
 512
 513 /* ------------------------------------------------------------------------ */
 514 /* Function:    ipf_proxy_flush                                             */
 515 /* Returns:     Nil                                                         */
 516 /* Parameters:  arg(I)   - pointer to proxy contect data                    */
 517 /*              how(I)   - indicates the type of flush operation            */
 518 /*                                                                          */
 519 /* Walk through all of the proxies and pass on the flush command as either  */
 520 /* a flush or a clear.                                                      */
 521 /* ------------------------------------------------------------------------ */
 522 void
 523 ipf_proxy_flush(arg, how)
 524         void *arg;
 525         int how;
 526 {
 527         ipf_proxy_softc_t *softp = arg;
 528         aproxy_t *ap;
 529
 530         switch (how)
 531         {
 532         case 0 :
 533                 for (ap = softp->ips_proxies; ap; ap = ap->apr_next)
 534                         if (ap->apr_flush != NULL)
 535                                 (*ap->apr_flush)(ap, how);
 536                 break;
 537         case 1 :
 538                 for (ap = softp->ips_proxies; ap; ap = ap->apr_next)
 539                         if (ap->apr_clear != NULL)
 540                                 (*ap->apr_clear)(ap);
 541                 break;
 542         default :
 543                 break;
 544         }
 545 }
 546
 547
 548 /* ------------------------------------------------------------------------ */
 549 /* Function:    ipf_proxy_add                                               */
 550 /* Returns:     int   - 0 == success, else failure.                         */
 551 /* Parameters:  ap(I) - pointer to proxy structure                          */
 552 /*                                                                          */
 553 /* Dynamically add a new kernel proxy.  Ensure that it is unique in the     */
 554 /* collection compiled in and dynamically added.                            */
 555 /* ------------------------------------------------------------------------ */
 556 int
 557 ipf_proxy_add(arg, ap)
 558         void *arg;
 559         aproxy_t *ap;
 560 {
 561         ipf_proxy_softc_t *softp = arg;
 562
 563         aproxy_t *a;
 564
 565         for (a = ips_proxies; a->apr_p; a++)
 566                 if ((a->apr_p == ap->apr_p) &&
 567                     !strncmp(a->apr_label, ap->apr_label,
 568                              sizeof(ap->apr_label))) {
 569                         if (softp->ips_proxy_debug & 0x01)
 570                                 printf("ipf_proxy_add: %s/%d present (B)\n",
 571                                        a->apr_label, a->apr_p);
 572                         return -1;
 573                 }
 574
 575         for (a = ap_proxylist; (a != NULL); a = a->apr_next)
 576                 if ((a->apr_p == ap->apr_p) &&
 577                     !strncmp(a->apr_label, ap->apr_label,
 578                              sizeof(ap->apr_label))) {
 579                         if (softp->ips_proxy_debug & 0x01)
 580                                 printf("ipf_proxy_add: %s/%d present (D)\n",
 581                                        a->apr_label, a->apr_p);
 582                         return -1;
 583                 }
 584         ap->apr_next = ap_proxylist;
 585         ap_proxylist = ap;
 586         if (ap->apr_load != NULL)
 587                 (*ap->apr_load)();
 588         return 0;
 589 }
 590
 591
 592 /* ------------------------------------------------------------------------ */
 593 /* Function:    ipf_proxy_ctl                                               */
 594 /* Returns:     int    - 0 == success, else error                           */
 595 /* Parameters:  softc(I) - pointer to soft context main structure           */
 596 /*              arg(I)   - pointer to proxy context                         */
 597 /*              ctl(I)   - pointer to proxy control structure               */
 598 /*                                                                          */
 599 /* Check to see if the proxy this control request has come through for      */
 600 /* exists, and if it does and it has a control function then invoke that    */
 601 /* control function.                                                        */
 602 /* ------------------------------------------------------------------------ */
 603 int
 604 ipf_proxy_ctl(softc, arg, ctl)
 605         ipf_main_softc_t *softc;
 606         void *arg;
 607         ap_ctl_t *ctl;
 608 {
 609         ipf_proxy_softc_t *softp = arg;
 610         aproxy_t *a;
 611         int error;
 612
 613         a = ipf_proxy_lookup(arg, ctl->apc_p, ctl->apc_label);
 614         if (a == NULL) {
 615                 if (softp->ips_proxy_debug & 0x01)
 616                         printf("ipf_proxy_ctl: can't find %s/%d\n",
 617                                 ctl->apc_label, ctl->apc_p);
 618                 IPFERROR(80001);
 619                 error = ESRCH;
 620         } else if (a->apr_ctl == NULL) {
 621                 if (softp->ips_proxy_debug & 0x01)
 622                         printf("ipf_proxy_ctl: no ctl function for %s/%d\n",
 623                                 ctl->apc_label, ctl->apc_p);
 624                 IPFERROR(80002);
 625                 error = ENXIO;
 626         } else {
 627                 error = (*a->apr_ctl)(softc, a->apr_soft, ctl);
 628                 if ((error != 0) && (softp->ips_proxy_debug & 0x02))
 629                         printf("ipf_proxy_ctl: %s/%d ctl error %d\n",
 630                                 a->apr_label, a->apr_p, error);
 631         }
 632         return error;
 633 }
 634
 635
 636 /* ------------------------------------------------------------------------ */
 637 /* Function:    ipf_proxy_del                                               */
 638 /* Returns:     int   - 0 == success, else failure.                         */
 639 /* Parameters:  ap(I) - pointer to proxy structure                          */
 640 /*                                                                          */
 641 /* Delete a proxy that has been added dynamically from those available.     */
 642 /* If it is in use, return 1 (do not destroy NOW), not in use 0 or -1       */
 643 /* if it cannot be matched.                                                 */
 644 /* ------------------------------------------------------------------------ */
 645 int
 646 ipf_proxy_del(ap)
 647         aproxy_t *ap;
 648 {
 649         aproxy_t *a, **app;
 650
 651         for (app = &ap_proxylist; ((a = *app) != NULL); app = &a->apr_next) {
 652                 if (a == ap) {
 653                         a->apr_flags |= APR_DELETE;
 654                         if (ap->apr_ref == 0 && ap->apr_clones == 0) {
 655                                 *app = a->apr_next;
 656                                 return 0;
 657                         }
 658                         return 1;
 659                 }
 660         }
 661
 662         return -1;
 663 }
 664
 665
 666 /* ------------------------------------------------------------------------ */
 667 /* Function:    ipf_proxy_ok                                                */
 668 /* Returns:     int    - 1 == good match else not.                          */
 669 /* Parameters:  fin(I) - pointer to packet information                      */
 670 /*              tcp(I) - pointer to TCP/UDP header                          */
 671 /*              nat(I) - pointer to current NAT session                     */
 672 /*                                                                          */
 673 /* This function extends the NAT matching to ensure that a packet that has  */
 674 /* arrived matches the proxy information attached to the NAT rule. Notably, */
 675 /* if the proxy is scheduled to be deleted then packets will not match the  */
 676 /* rule even if the rule is still active.                                   */
 677 /* ------------------------------------------------------------------------ */
 678 int
 679 ipf_proxy_ok(fin, tcp, np)
 680         fr_info_t *fin;
 681         tcphdr_t *tcp;
 682         ipnat_t *np;
 683 {
 684         aproxy_t *apr = np->in_apr;
 685         u_short dport = np->in_odport;
 686
 687         if ((apr == NULL) || (apr->apr_flags & APR_DELETE) ||
 688             (fin->fin_p != apr->apr_p))
 689                 return 0;
 690         if ((tcp == NULL) && dport)
 691                 return 0;
 692         return 1;
 693 }
 694
 695
 696 /* ------------------------------------------------------------------------ */
 697 /* Function:    ipf_proxy_ioctl                                             */
 698 /* Returns:     int    - 0 == success, else error                           */
 699 /* Parameters:  softc(I) - pointer to soft context main structure           */
 700 /*              data(I)  - pointer to ioctl data                            */
 701 /*              cmd(I)   - ioctl command                                    */
 702 /*              mode(I)  - mode bits for device                             */
 703 /*              ctx(I)   - pointer to context information                   */
 704 /*                                                                          */
 705 /* ------------------------------------------------------------------------ */
 706 int
 707 ipf_proxy_ioctl(softc, data, cmd, mode, ctx)
 708         ipf_main_softc_t *softc;
 709         caddr_t data;
 710         ioctlcmd_t cmd;
 711         int mode;
 712         void *ctx;
 713 {
 714         ap_ctl_t ctl;
 715         caddr_t ptr;
 716         int error;
 717
 718         mode = mode;    /* LINT */
 719
 720         switch (cmd)
 721         {
 722         case SIOCPROXY :
 723                 error = ipf_inobj(softc, data, NULL, &ctl, IPFOBJ_PROXYCTL);
 724                 if (error != 0) {
 725                         return error;
 726                 }
 727                 ptr = NULL;
 728
 729                 if (ctl.apc_dsize > 0) {
 730                         KMALLOCS(ptr, caddr_t, ctl.apc_dsize);
 731                         if (ptr == NULL) {
 732                                 IPFERROR(80003);
 733                                 error = ENOMEM;
 734                         } else {
 735                                 error = copyinptr(softc, ctl.apc_data, ptr,
 736                                                   ctl.apc_dsize);
 737                                 if (error == 0)
 738                                         ctl.apc_data = ptr;
 739                         }
 740                 } else {
 741                         ctl.apc_data = NULL;
 742                         error = 0;
 743                 }
 744
 745                 if (error == 0)
 746                         error = ipf_proxy_ctl(softc, softc->ipf_proxy_soft,
 747                                               &ctl);
 748
 749                 if ((error != 0) && (ptr != NULL)) {
 750                         KFREES(ptr, ctl.apc_dsize);
 751                 }
 752                 break;
 753
 754         default :
 755                 IPFERROR(80004);
 756                 error = EINVAL;
 757         }
 758         return error;
 759 }
 760
 761
 762 /* ------------------------------------------------------------------------ */
 763 /* Function:    ipf_proxy_match                                             */
 764 /* Returns:     int    - 0 == success, else error                           */
 765 /* Parameters:  fin(I) - pointer to packet information                      */
 766 /*              nat(I) - pointer to current NAT session                     */
 767 /*                                                                          */
 768 /* If a proxy has a match function, call that to do extended packet         */
 769 /* matching. Whilst other parts of the NAT code are rather lenient when it  */
 770 /* comes to the quality of the packet that it will transform, the proxy     */
 771 /* matching is not because they need to work with data, not just headers.   */
 772 /* ------------------------------------------------------------------------ */
 773 int
 774 ipf_proxy_match(fin, nat)
 775         fr_info_t *fin;
 776         nat_t *nat;
 777 {
 778         ipf_main_softc_t *softc = fin->fin_main_soft;
 779         ipf_proxy_softc_t *softp = softc->ipf_proxy_soft;
 780         aproxy_t *apr;
 781         ipnat_t *ipn;
 782         int result;
 783
 784         ipn = nat->nat_ptr;
 785         if (softp->ips_proxy_debug & 0x04)
 786                 printf("ipf_proxy_match(%lx,%lx) aps %lx ptr %lx\n",
 787                         (u_long)fin, (u_long)nat, (u_long)nat->nat_aps,
 788                         (u_long)ipn);
 789
 790         if ((fin->fin_flx & (FI_SHORT|FI_BAD)) != 0) {
 791                 if (softp->ips_proxy_debug & 0x08)
 792                         printf("ipf_proxy_match: flx 0x%x (BAD|SHORT)\n",
 793                                 fin->fin_flx);
 794                 return -1;
 795         }
 796
 797         apr = ipn->in_apr;
 798         if ((apr == NULL) || (apr->apr_flags & APR_DELETE)) {
 799                 if (softp->ips_proxy_debug & 0x08)
 800                         printf("ipf_proxy_match:apr %lx apr_flags 0x%x\n",
 801                                 (u_long)apr, apr ? apr->apr_flags : 0);
 802                 return -1;
 803         }
 804
 805         if (apr->apr_match != NULL) {
 806                 result = (*apr->apr_match)(fin, nat->nat_aps, nat);
 807                 if (result != 0) {
 808                         if (softp->ips_proxy_debug & 0x08)
 809                                 printf("ipf_proxy_match: result %d\n", result);
 810                         return -1;
 811                 }
 812         }
 813         return 0;
 814 }
 815
 816
 817 /* ------------------------------------------------------------------------ */
 818 /* Function:    ipf_proxy_new                                               */
 819 /* Returns:     int    - 0 == success, else error                           */
 820 /* Parameters:  fin(I) - pointer to packet information                      */
 821 /*              nat(I) - pointer to current NAT session                     */
 822 /*                                                                          */
 823 /* Allocate a new application proxy structure and fill it in with the       */
 824 /* relevant details.  call the init function once complete, prior to        */
 825 /* returning.                                                               */
 826 /* ------------------------------------------------------------------------ */
 827 int
 828 ipf_proxy_new(fin, nat)
 829         fr_info_t *fin;
 830         nat_t *nat;
 831 {
 832         ipf_main_softc_t *softc = fin->fin_main_soft;
 833         ipf_proxy_softc_t *softp = softc->ipf_proxy_soft;
 834         register ap_session_t *aps;
 835         aproxy_t *apr;
 836
 837         if (softp->ips_proxy_debug & 0x04)
 838                 printf("ipf_proxy_new(%lx,%lx) \n", (u_long)fin, (u_long)nat);
 839
 840         if ((nat->nat_ptr == NULL) || (nat->nat_aps != NULL)) {
 841                 if (softp->ips_proxy_debug & 0x08)
 842                         printf("ipf_proxy_new: nat_ptr %lx nat_aps %lx\n",
 843                                 (u_long)nat->nat_ptr, (u_long)nat->nat_aps);
 844                 return -1;
 845         }
 846
 847         apr = nat->nat_ptr->in_apr;
 848
 849         if ((apr->apr_flags & APR_DELETE) ||
 850             (fin->fin_p != apr->apr_p)) {
 851                 if (softp->ips_proxy_debug & 0x08)
 852                         printf("ipf_proxy_new: apr_flags 0x%x p %d/%d\n",
 853                                 apr->apr_flags, fin->fin_p, apr->apr_p);
 854                 return -1;
 855         }
 856
 857         KMALLOC(aps, ap_session_t *);
 858         if (!aps) {
 859                 if (softp->ips_proxy_debug & 0x08)
 860                         printf("ipf_proxy_new: malloc failed (%lu)\n",
 861                                 (u_long)sizeof(ap_session_t));
 862                 return -1;
 863         }
 864
 865         bzero((char *)aps, sizeof(*aps));
 866         aps->aps_data = NULL;
 867         aps->aps_apr = apr;
 868         aps->aps_psiz = 0;
 869         if (apr->apr_new != NULL)
 870                 if ((*apr->apr_new)(apr->apr_soft, fin, aps, nat) == -1) {
 871                         if ((aps->aps_data != NULL) && (aps->aps_psiz != 0)) {
 872                                 KFREES(aps->aps_data, aps->aps_psiz);
 873                         }
 874                         KFREE(aps);
 875                         if (softp->ips_proxy_debug & 0x08)
 876                                 printf("ipf_proxy_new: new(%lx) failed\n",
 877                                         (u_long)apr->apr_new);
 878                         return -1;
 879                 }
 880         aps->aps_nat = nat;
 881         aps->aps_next = softp->ips_sess_list;
 882         softp->ips_sess_list = aps;
 883         nat->nat_aps = aps;
 884
 885         return 0;
 886 }
 887
 888
 889 /* ------------------------------------------------------------------------ */
 890 /* Function:    ipf_proxy_check                                             */
 891 /* Returns:     int - -1 == error, 0 == success                             */
 892 /* Parameters:  fin(I) - pointer to packet information                      */
 893 /*              nat(I) - pointer to current NAT session                     */
 894 /*                                                                          */
 895 /* Check to see if a packet should be passed through an active proxy        */
 896 /* routine if one has been setup for it.  We don't need to check the        */
 897 /* checksum here if IPFILTER_CKSUM is defined because if it is, a failed    */
 898 /* check causes FI_BAD to be set.                                           */
 899 /* ------------------------------------------------------------------------ */
 900 int
 901 ipf_proxy_check(fin, nat)
 902         fr_info_t *fin;
 903         nat_t *nat;
 904 {
 905         ipf_main_softc_t *softc = fin->fin_main_soft;
 906         ipf_proxy_softc_t *softp = softc->ipf_proxy_soft;
 907 #if SOLARIS && defined(_KERNEL) && defined(ICK_VALID)
 908         mb_t *m;
 909 #endif
 910         tcphdr_t *tcp = NULL;
 911         udphdr_t *udp = NULL;
 912         ap_session_t *aps;
 913         aproxy_t *apr;
 914         short adjlen;
 915         int dosum;
 916         ip_t *ip;
 917         short rv;
 918         int err;
 919 #if !defined(_KERNEL) || defined(MENTAT) || defined(__sgi)
 920         u_32_t s1, s2, sd;
 921 #endif
 922
 923         if (fin->fin_flx & FI_BAD) {
 924                 if (softp->ips_proxy_debug & 0x08)
 925                         printf("ipf_proxy_check: flx 0x%x (BAD)\n",
 926                                fin->fin_flx);
 927                 return -1;
 928         }
 929
 930 #ifndef IPFILTER_CKSUM
 931         if ((fin->fin_out == 0) && (ipf_checkl4sum(fin) == -1)) {
 932                 if (softp->ips_proxy_debug & 0x08)
 933                         printf("ipf_proxy_check: l4 checksum failure %d\n",
 934                                 fin->fin_p);
 935                 if (fin->fin_p == IPPROTO_TCP)
 936                         softc->ipf_stats[fin->fin_out].fr_tcpbad++;
 937                 return -1;
 938         }
 939 #endif
 940
 941         aps = nat->nat_aps;
 942         if (aps != NULL) {
 943                 /*
 944                  * If there is data in this packet to be proxied then try and
 945                  * get it all into the one buffer, else drop it.
 946                  */
 947 #if defined(MENTAT) || defined(HAVE_M_PULLDOWN)
 948                 if ((fin->fin_dlen > 0) && !(fin->fin_flx & FI_COALESCE))
 949                         if (ipf_coalesce(fin) == -1) {
 950                                 if (softp->ips_proxy_debug & 0x08)
 951                                         printf("ipf_proxy_check: %s %x\n",
 952                                                "coalesce failed", fin->fin_flx);
 953                                 return -1;
 954                         }
 955 #endif
 956                 ip = fin->fin_ip;
 957                 if (fin->fin_cksum > FI_CK_SUMOK)
 958                         dosum = 0;
 959                 else
 960                         dosum = 1;
 961
 962                 switch (fin->fin_p)
 963                 {
 964                 case IPPROTO_TCP :
 965                         tcp = (tcphdr_t *)fin->fin_dp;
 966 #if SOLARIS && defined(_KERNEL) && defined(ICK_VALID)
 967                         m = fin->fin_qfm;
 968                         if (dohwcksum && (m->b_ick_flag == ICK_VALID))
 969                                 dosum = 0;
 970 #endif
 971                         break;
 972                 case IPPROTO_UDP :
 973                         udp = (udphdr_t *)fin->fin_dp;
 974                         break;
 975                 default :
 976                         break;
 977                 }
 978
 979                 apr = aps->aps_apr;
 980                 err = 0;
 981                 if (fin->fin_out != 0) {
 982                         if (apr->apr_outpkt != NULL)
 983                                 err = (*apr->apr_outpkt)(apr->apr_soft, fin,
 984                                                          aps, nat);
 985                 } else {
 986                         if (apr->apr_inpkt != NULL)
 987                                 err = (*apr->apr_inpkt)(apr->apr_soft, fin,
 988                                                         aps, nat);
 989                 }
 990
 991                 rv = APR_EXIT(err);
 992                 if (((softp->ips_proxy_debug & 0x08) && (rv != 0)) ||
 993                     (softp->ips_proxy_debug & 0x04))
 994                         printf("ipf_proxy_check: out %d err %x rv %d\n",
 995                                 fin->fin_out, err, rv);
 996                 if (rv == 1)
 997                         return -1;
 998
 999                 if (rv == 2) {
1000                         ipf_proxy_deref(apr);
1001                         nat->nat_aps = NULL;
1002                         return -1;
1003                 }
1004
1005                 /*
1006                  * If err != 0 then the data size of the packet has changed
1007                  * so we need to recalculate the header checksums for the
1008                  * packet.
1009                  */
1010                 adjlen = APR_INC(err);
1011 #if !defined(_KERNEL) || defined(MENTAT) || defined(__sgi)
1012                 s1 = LONG_SUM(fin->fin_plen - adjlen);
1013                 s2 = LONG_SUM(fin->fin_plen);
1014                 CALC_SUMD(s1, s2, sd);
1015                 if ((err != 0) && (fin->fin_cksum < FI_CK_L4PART) &&
1016                     fin->fin_v == 4)
1017                         ipf_fix_outcksum(0, &ip->ip_sum, sd, 0);
1018 #endif
1019                 if (fin->fin_flx & FI_DOCKSUM)
1020                         dosum = 1;
1021
1022                 /*
1023                  * For TCP packets, we may need to adjust the sequence and
1024                  * acknowledgement numbers to reflect changes in size of the
1025                  * data stream.
1026                  *
1027                  * For both TCP and UDP, recalculate the layer 4 checksum,
1028                  * regardless, as we can't tell (here) if data has been
1029                  * changed or not.
1030                  */
1031                 if (tcp != NULL) {
1032                         err = ipf_proxy_fixseqack(fin, ip, aps, adjlen);
1033                         if (fin->fin_cksum == FI_CK_L4PART) {
1034                                 u_short sum = ntohs(tcp->th_sum);
1035                                 sum += adjlen;
1036                                 tcp->th_sum = htons(sum);
1037                         } else if (fin->fin_cksum < FI_CK_L4PART) {
1038                                 tcp->th_sum = fr_cksum(fin, ip,
1039                                                        IPPROTO_TCP, tcp);
1040                         }
1041                 } else if ((udp != NULL) && (udp->uh_sum != 0)) {
1042                         if (fin->fin_cksum == FI_CK_L4PART) {
1043                                 u_short sum = ntohs(udp->uh_sum);
1044                                 sum += adjlen;
1045                                 udp->uh_sum = htons(sum);
1046                         } else if (dosum) {
1047                                 udp->uh_sum = fr_cksum(fin, ip,
1048                                                        IPPROTO_UDP, udp);
1049                         }
1050                 }
1051                 aps->aps_bytes += fin->fin_plen;
1052                 aps->aps_pkts++;
1053                 return 1;
1054         }
1055         return 0;
1056 }
1057
1058
1059 /* ------------------------------------------------------------------------ */
1060 /* Function:    ipf_proxy_lookup                                            */
1061 /* Returns:     int - -1 == error, 0 == success                             */
1062 /* Parameters:  arg(I)  - pointer to proxy context information              */
1063 /*              pr(I)   - protocol number for proxy                         */
1064 /*              name(I) - proxy name                                        */
1065 /*                                                                          */
1066 /* Search for an proxy by the protocol it is being used with and its name.  */
1067 /* ------------------------------------------------------------------------ */
1068 aproxy_t *
1069 ipf_proxy_lookup(arg, pr, name)
1070         void *arg;
1071         u_int pr;
1072         char *name;
1073 {
1074         ipf_proxy_softc_t *softp = arg;
1075         aproxy_t *ap;
1076
1077         if (softp->ips_proxy_debug & 0x04)
1078                 printf("ipf_proxy_lookup(%d,%s)\n", pr, name);
1079
1080         for (ap = softp->ips_proxies; ap != NULL; ap = ap->apr_next)
1081                 if ((ap->apr_p == pr) &&
1082                     !strncmp(name, ap->apr_label, sizeof(ap->apr_label))) {
1083                         ap->apr_ref++;
1084                         return ap;
1085                 }
1086
1087         if (softp->ips_proxy_debug & 0x08)
1088                 printf("ipf_proxy_lookup: failed for %d/%s\n", pr, name);
1089         return NULL;
1090 }
1091
1092
1093 /* ------------------------------------------------------------------------ */
1094 /* Function:    ipf_proxy_deref                                             */
1095 /* Returns:     Nil                                                         */
1096 /* Parameters:  ap(I) - pointer to proxy structure                          */
1097 /*                                                                          */
1098 /* Drop the reference counter associated with the proxy.                    */
1099 /* ------------------------------------------------------------------------ */
1100 void
1101 ipf_proxy_deref(ap)
1102         aproxy_t *ap;
1103 {
1104         ap->apr_ref--;
1105 }
1106
1107
1108 /* ------------------------------------------------------------------------ */
1109 /* Function:    ipf_proxy_free                                              */
1110 /* Returns:     Nil                                                         */
1111 /* Parameters:  softc(I) - pointer to soft context main structure           */
1112 /*              aps(I)   - pointer to current proxy session                 */
1113 /* Locks Held:  ipf_nat_new, ipf_nat(W)                                     */
1114 /*                                                                          */
1115 /* Free up proxy session information allocated to be used with a NAT        */
1116 /* session.                                                                 */
1117 /* ------------------------------------------------------------------------ */
1118 void
1119 ipf_proxy_free(softc, aps)
1120         ipf_main_softc_t *softc;
1121         ap_session_t *aps;
1122 {
1123         ipf_proxy_softc_t *softp = softc->ipf_proxy_soft;
1124         ap_session_t *a, **ap;
1125         aproxy_t *apr;
1126
1127         if (!aps)
1128                 return;
1129
1130         for (ap = &softp->ips_sess_list; ((a = *ap) != NULL); ap = &a->aps_next)
1131                 if (a == aps) {
1132                         *ap = a->aps_next;
1133                         break;
1134                 }
1135
1136         apr = aps->aps_apr;
1137         if ((apr != NULL) && (apr->apr_del != NULL))
1138                 (*apr->apr_del)(softc, aps);
1139
1140         if ((aps->aps_data != NULL) && (aps->aps_psiz != 0))
1141                 KFREES(aps->aps_data, aps->aps_psiz);
1142         KFREE(aps);
1143 }
1144
1145
1146 /* ------------------------------------------------------------------------ */
1147 /* Function:    ipf_proxy_fixseqack                                         */
1148 /* Returns:     int    - 2 if TCP ack/seq is changed, else 0                */
1149 /* Parameters:  fin(I) - pointer to packet information                      */
1150 /*              ip(I)  - pointer to IP header                               */
1151 /*              nat(I) - pointer to current NAT session                     */
1152 /*              inc(I) - delta to apply to TCP sequence numbering           */
1153 /*                                                                          */
1154 /* Adjust the TCP sequence/acknowledge numbers in the TCP header based on   */
1155 /* whether or not the new header is past the point at which an adjustment   */
1156 /* occurred. This might happen because of (say) an FTP string being changed */
1157 /* and the new string being a different length to the old.                  */
1158 /* ------------------------------------------------------------------------ */
1159 static int
1160 ipf_proxy_fixseqack(fin, ip, aps, inc)
1161         fr_info_t *fin;
1162         ip_t *ip;
1163         ap_session_t *aps;
1164         int inc;
1165 {
1166         ipf_main_softc_t *softc = fin->fin_main_soft;
1167         ipf_proxy_softc_t *softp = softc->ipf_proxy_soft;
1168         int sel, ch = 0, out, nlen;
1169         u_32_t seq1, seq2;
1170         tcphdr_t *tcp;
1171         short inc2;
1172
1173         tcp = (tcphdr_t *)fin->fin_dp;
1174         out = fin->fin_out;
1175         /*
1176          * ip_len has already been adjusted by 'inc'.
1177          */
1178         nlen = fin->fin_dlen;
1179         nlen -= (TCP_OFF(tcp) << 2);
1180
1181         inc2 = inc;
1182         inc = (int)inc2;
1183
1184         if (out != 0) {
1185                 seq1 = (u_32_t)ntohl(tcp->th_seq);
1186                 sel = aps->aps_sel[out];
1187
1188                 /* switch to other set ? */
1189                 if ((aps->aps_seqmin[!sel] > aps->aps_seqmin[sel]) &&
1190                     (seq1 > aps->aps_seqmin[!sel])) {
1191                         if (softp->ips_proxy_debug & 0x10)
1192                                 printf("proxy out switch set seq %d -> %d %x > %x\n",
1193                                         sel, !sel, seq1,
1194                                         aps->aps_seqmin[!sel]);
1195                         sel = aps->aps_sel[out] = !sel;
1196                 }
1197
1198                 if (aps->aps_seqoff[sel]) {
1199                         seq2 = aps->aps_seqmin[sel] - aps->aps_seqoff[sel];
1200                         if (seq1 > seq2) {
1201                                 seq2 = aps->aps_seqoff[sel];
1202                                 seq1 += seq2;
1203                                 tcp->th_seq = htonl(seq1);
1204                                 ch = 1;
1205                         }
1206                 }
1207
1208                 if (inc && (seq1 > aps->aps_seqmin[!sel])) {
1209                         aps->aps_seqmin[sel] = seq1 + nlen - 1;
1210                         aps->aps_seqoff[sel] = aps->aps_seqoff[sel] + inc;
1211                         if (softp->ips_proxy_debug & 0x10)
1212                                 printf("proxy seq set %d at %x to %d + %d\n",
1213                                         sel, aps->aps_seqmin[sel],
1214                                         aps->aps_seqoff[sel], inc);
1215                 }
1216
1217                 /***/
1218
1219                 seq1 = ntohl(tcp->th_ack);
1220                 sel = aps->aps_sel[1 - out];
1221
1222                 /* switch to other set ? */
1223                 if ((aps->aps_ackmin[!sel] > aps->aps_ackmin[sel]) &&
1224                     (seq1 > aps->aps_ackmin[!sel])) {
1225                         if (softp->ips_proxy_debug & 0x10)
1226                                 printf("proxy out switch set ack %d -> %d %x > %x\n",
1227                                         sel, !sel, seq1,
1228                                         aps->aps_ackmin[!sel]);
1229                         sel = aps->aps_sel[1 - out] = !sel;
1230                 }
1231
1232                 if (aps->aps_ackoff[sel] && (seq1 > aps->aps_ackmin[sel])) {
1233                         seq2 = aps->aps_ackoff[sel];
1234                         tcp->th_ack = htonl(seq1 - seq2);
1235                         ch = 1;
1236                 }
1237         } else {
1238                 seq1 = ntohl(tcp->th_seq);
1239                 sel = aps->aps_sel[out];
1240
1241                 /* switch to other set ? */
1242                 if ((aps->aps_ackmin[!sel] > aps->aps_ackmin[sel]) &&
1243                     (seq1 > aps->aps_ackmin[!sel])) {
1244                         if (softp->ips_proxy_debug & 0x10)
1245                                 printf("proxy in switch set ack %d -> %d %x > %x\n",
1246                                         sel, !sel, seq1, aps->aps_ackmin[!sel]);
1247                         sel = aps->aps_sel[out] = !sel;
1248                 }
1249
1250                 if (aps->aps_ackoff[sel]) {
1251                         seq2 = aps->aps_ackmin[sel] - aps->aps_ackoff[sel];
1252                         if (seq1 > seq2) {
1253                                 seq2 = aps->aps_ackoff[sel];
1254                                 seq1 += seq2;
1255                                 tcp->th_seq = htonl(seq1);
1256                                 ch = 1;
1257                         }
1258                 }
1259
1260                 if (inc && (seq1 > aps->aps_ackmin[!sel])) {
1261                         aps->aps_ackmin[!sel] = seq1 + nlen - 1;
1262                         aps->aps_ackoff[!sel] = aps->aps_ackoff[sel] + inc;
1263
1264                         if (softp->ips_proxy_debug & 0x10)
1265                                 printf("proxy ack set %d at %x to %d + %d\n",
1266                                         !sel, aps->aps_seqmin[!sel],
1267                                         aps->aps_seqoff[sel], inc);
1268                 }
1269
1270                 /***/
1271
1272                 seq1 = ntohl(tcp->th_ack);
1273                 sel = aps->aps_sel[1 - out];
1274
1275                 /* switch to other set ? */
1276                 if ((aps->aps_seqmin[!sel] > aps->aps_seqmin[sel]) &&
1277                     (seq1 > aps->aps_seqmin[!sel])) {
1278                         if (softp->ips_proxy_debug & 0x10)
1279                                 printf("proxy in switch set seq %d -> %d %x > %x\n",
1280                                         sel, !sel, seq1, aps->aps_seqmin[!sel]);
1281                         sel = aps->aps_sel[1 - out] = !sel;
1282                 }
1283
1284                 if (aps->aps_seqoff[sel] != 0) {
1285                         if (softp->ips_proxy_debug & 0x10)
1286                                 printf("sel %d seqoff %d seq1 %x seqmin %x\n",
1287                                         sel, aps->aps_seqoff[sel], seq1,
1288                                         aps->aps_seqmin[sel]);
1289                         if (seq1 > aps->aps_seqmin[sel]) {
1290                                 seq2 = aps->aps_seqoff[sel];
1291                                 tcp->th_ack = htonl(seq1 - seq2);
1292                                 ch = 1;
1293                         }
1294                 }
1295         }
1296
1297         if (softp->ips_proxy_debug & 0x10)
1298                 printf("ipf_proxy_fixseqack: seq %u ack %u\n",
1299                         (u_32_t)ntohl(tcp->th_seq), (u_32_t)ntohl(tcp->th_ack));
1300         return ch ? 2 : 0;
1301 }
1302
1303
1304 /* ------------------------------------------------------------------------ */
1305 /* Function:    ipf_proxy_rule_rev                                          */
1306 /* Returns:     ipnat_t * - NULL = failure, else pointer to new rule        */
1307 /* Parameters:  nat(I) - pointer to NAT session to create rule from         */
1308 /*                                                                          */
1309 /* This function creates a NAT rule that is based upon the reverse packet   */
1310 /* flow associated with this NAT session. Thus if this NAT session was      */
1311 /* created with a map rule then this function will create a rdr rule.       */
1312 /* Only address fields and network interfaces are assigned in this function */
1313 /* and the address fields are formed such that an exact is required. If the */
1314 /* original rule had a netmask, that is not replicated here not is it       */
1315 /* desired. The ultimate goal here is to create a NAT rule to support a NAT */
1316 /* session being created that does not have a user configured rule. The     */
1317 /* classic example is supporting the FTP proxy, where a data channel needs  */
1318 /* to be setup, based on the addresses used for the control connection. In  */
1319 /* that case, this function is used to handle creating NAT rules to support */
1320 /* data connections with the PORT and EPRT commands.                        */
1321 /* ------------------------------------------------------------------------ */
1322 ipnat_t *
1323 ipf_proxy_rule_rev(nat)
1324         nat_t *nat;
1325 {
1326         ipnat_t *old;
1327         ipnat_t *ipn;
1328         int size;
1329
1330         old = nat->nat_ptr;
1331         size = old->in_size;
1332
1333         KMALLOCS(ipn, ipnat_t *, size);
1334         if (ipn == NULL)
1335                 return NULL;
1336
1337         bzero((char *)ipn, size);
1338
1339         ipn->in_use = 1;
1340         ipn->in_hits = 1;
1341         ipn->in_ippip = 1;
1342         ipn->in_apr = NULL;
1343         ipn->in_size = size;
1344         ipn->in_pr[0] = old->in_pr[1];
1345         ipn->in_pr[1] = old->in_pr[0];
1346         ipn->in_v[0] = old->in_v[1];
1347         ipn->in_v[1] = old->in_v[0];
1348         ipn->in_ifps[0] = old->in_ifps[1];
1349         ipn->in_ifps[1] = old->in_ifps[0];
1350         ipn->in_flags = (old->in_flags | IPN_PROXYRULE);
1351
1352         ipn->in_nsrcip6 = nat->nat_odst6;
1353         ipn->in_osrcip6 = nat->nat_ndst6;
1354
1355         if ((old->in_redir & NAT_REDIRECT) != 0) {
1356                 ipn->in_redir = NAT_MAP;
1357                 if (ipn->in_v[0] == 4) {
1358                         ipn->in_snip = ntohl(nat->nat_odstaddr);
1359                         ipn->in_dnip = ntohl(nat->nat_nsrcaddr);
1360                 } else {
1361 #ifdef USE_INET6
1362                         ipn->in_snip6 = nat->nat_odst6;
1363                         ipn->in_dnip6 = nat->nat_nsrc6;
1364 #endif
1365                 }
1366                 ipn->in_ndstip6 = nat->nat_nsrc6;
1367                 ipn->in_odstip6 = nat->nat_osrc6;
1368         } else {
1369                 ipn->in_redir = NAT_REDIRECT;
1370                 if (ipn->in_v[0] == 4) {
1371                         ipn->in_snip = ntohl(nat->nat_odstaddr);
1372                         ipn->in_dnip = ntohl(nat->nat_osrcaddr);
1373                 } else {
1374 #ifdef USE_INET6
1375                         ipn->in_snip6 = nat->nat_odst6;
1376                         ipn->in_dnip6 = nat->nat_osrc6;
1377 #endif
1378                 }
1379                 ipn->in_ndstip6 = nat->nat_osrc6;
1380                 ipn->in_odstip6 = nat->nat_nsrc6;
1381         }
1382
1383         IP6_SETONES(&ipn->in_osrcmsk6);
1384         IP6_SETONES(&ipn->in_nsrcmsk6);
1385         IP6_SETONES(&ipn->in_odstmsk6);
1386         IP6_SETONES(&ipn->in_ndstmsk6);
1387
1388         ipn->in_namelen = old->in_namelen;
1389         ipn->in_ifnames[0] = old->in_ifnames[1];
1390         ipn->in_ifnames[1] = old->in_ifnames[0];
1391         bcopy(old->in_names, ipn->in_names, ipn->in_namelen);
1392         MUTEX_INIT(&ipn->in_lock, "ipnat rev rule lock");
1393
1394         return ipn;
1395 }
1396
1397
1398 /* ------------------------------------------------------------------------ */
1399 /* Function:    ipf_proxy_rule_fwd                                          */
1400 /* Returns:     ipnat_t * - NULL = failure, else pointer to new rule        */
1401 /* Parameters:  nat(I) - pointer to NAT session to create rule from         */
1402 /*                                                                          */
1403 /* The purpose and rationale of this function is much the same as the above */
1404 /* function, ipf_proxy_rule_rev, except that a rule is created that matches */
1405 /* the same direction as that of the existing NAT session. Thus if this NAT */
1406 /* session was created with a map rule then this function will also create  */
1407 /* a data structure to represent a map rule. Whereas ipf_proxy_rule_rev is  */
1408 /* used to support PORT/EPRT, this function supports PASV/EPSV.             */
1409 /* ------------------------------------------------------------------------ */
1410 ipnat_t *
1411 ipf_proxy_rule_fwd(nat)
1412         nat_t *nat;
1413 {
1414         ipnat_t *old;
1415         ipnat_t *ipn;
1416         int size;
1417
1418         old = nat->nat_ptr;
1419         size = old->in_size;
1420
1421         KMALLOCS(ipn, ipnat_t *, size);
1422         if (ipn == NULL)
1423                 return NULL;
1424
1425         bzero((char *)ipn, size);
1426
1427         ipn->in_use = 1;
1428         ipn->in_hits = 1;
1429         ipn->in_ippip = 1;
1430         ipn->in_apr = NULL;
1431         ipn->in_size = size;
1432         ipn->in_pr[0] = old->in_pr[0];
1433         ipn->in_pr[1] = old->in_pr[1];
1434         ipn->in_v[0] = old->in_v[0];
1435         ipn->in_v[1] = old->in_v[1];
1436         ipn->in_ifps[0] = nat->nat_ifps[0];
1437         ipn->in_ifps[1] = nat->nat_ifps[1];
1438         ipn->in_flags = (old->in_flags | IPN_PROXYRULE);
1439
1440         ipn->in_nsrcip6 = nat->nat_nsrc6;
1441         ipn->in_osrcip6 = nat->nat_osrc6;
1442         ipn->in_ndstip6 = nat->nat_ndst6;
1443         ipn->in_odstip6 = nat->nat_odst6;
1444         ipn->in_redir = old->in_redir;
1445
1446         if (ipn->in_v[0] == 4) {
1447                 ipn->in_snip = ntohl(nat->nat_nsrcaddr);
1448                 ipn->in_dnip = ntohl(nat->nat_ndstaddr);
1449         } else {
1450 #ifdef USE_INET6
1451                 ipn->in_snip6 = nat->nat_nsrc6;
1452                 ipn->in_dnip6 = nat->nat_ndst6;
1453 #endif
1454         }
1455
1456         IP6_SETONES(&ipn->in_osrcmsk6);
1457         IP6_SETONES(&ipn->in_nsrcmsk6);
1458         IP6_SETONES(&ipn->in_odstmsk6);
1459         IP6_SETONES(&ipn->in_ndstmsk6);
1460
1461         ipn->in_namelen = old->in_namelen;
1462         ipn->in_ifnames[0] = old->in_ifnames[0];
1463         ipn->in_ifnames[1] = old->in_ifnames[1];
1464         bcopy(old->in_names, ipn->in_names, ipn->in_namelen);
1465         MUTEX_INIT(&ipn->in_lock, "ipnat fwd rule lock");
1466
1467         return ipn;
1468 }