sys/netpfil/ipfilter/netinet/ip_proxy.c

   1
   2 /*
   3  * Copyright (C) 2012 by Darren Reed.
   4  *
   5  * See the IPFILTER.LICENCE file for details on licencing.
   6  */
   7 #if defined(KERNEL) || defined(_KERNEL)
   8 # undef KERNEL
   9 # undef _KERNEL
  10 # define        KERNEL  1
  11 # define        _KERNEL 1
  12 #endif
  13 #include <sys/errno.h>
  14 #include <sys/types.h>
  15 #include <sys/param.h>
  16 #include <sys/time.h>
  17 #include <sys/file.h>
  18 # include <sys/fcntl.h>
  19 #if !defined(_KERNEL) && !defined(__KERNEL__)
  20 # include <stdio.h>
  21 # include <string.h>
  22 # include <stdlib.h>
  23 # include <ctype.h>
  24 # define _KERNEL
  25 # include <sys/uio.h>
  26 # undef _KERNEL
  27 #endif
  28 # include <sys/protosw.h>
  29 #include <sys/socket.h>
  30 #if defined(_KERNEL)
  31 #ifdef __FreeBSD__
  32 #  include <sys/ctype.h>
  33 # endif
  34 # include <sys/systm.h>
  35 # if !defined(__SVR4)
  36 #  include <sys/mbuf.h>
  37 # endif
  38 #endif
  39 #if defined(_KERNEL) && defined(__FreeBSD__)
  40 # include <sys/filio.h>
  41 # include <sys/fcntl.h>
  42 #else
  43 # include <sys/ioctl.h>
  44 #endif
  45 #if defined(__SVR4)
  46 # include <sys/byteorder.h>
  47 # ifdef _KERNEL
  48 #  include <sys/dditypes.h>
  49 # endif
  50 # include <sys/stream.h>
  51 # include <sys/kmem.h>
  52 #endif
  53 #ifdef __FreeBSD__
  54 # include <sys/queue.h>
  55 #endif
  56 #include <net/if.h>
  57 #if defined(__FreeBSD__) && defined(_KERNEL)
  58 #include <net/vnet.h>
  59 #else
  60 #define CURVNET_SET(arg)
  61 #define CURVNET_RESTORE()
  62 #define VNET_DEFINE(_t, _v)     _t _v
  63 #define VNET_DECLARE(_t, _v)    extern _t _v
  64 #define VNET(arg)       arg
  65 #endif
  66 #ifdef sun
  67 # include <net/af.h>
  68 #endif
  69 #include <netinet/in.h>
  70 #include <netinet/in_systm.h>
  71 #include <netinet/ip.h>
  72 # include <netinet/ip_var.h>
  73 #include <netinet/tcp.h>
  74 #include <netinet/udp.h>
  75 #include <netinet/ip_icmp.h>
  76 #include "netinet/ip_compat.h"
  77 #include <netinet/tcpip.h>
  78 #include "netinet/ip_fil.h"
  79 #include "netinet/ip_nat.h"
  80 #include "netinet/ip_state.h"
  81 #include "netinet/ip_proxy.h"
  82 #if defined(__FreeBSD__)
  83 # include <sys/malloc.h>
  84 #endif
  85
  86 /* END OF INCLUDES */
  87
  88 #include "netinet/ip_ftp_pxy.c"
  89 #include "netinet/ip_tftp_pxy.c"
  90 #include "netinet/ip_rcmd_pxy.c"
  91 #include "netinet/ip_pptp_pxy.c"
  92 #if defined(_KERNEL)
  93 # include "netinet/ip_irc_pxy.c"
  94 # include "netinet/ip_raudio_pxy.c"
  95 # include "netinet/ip_netbios_pxy.c"
  96 #endif
  97 #include "netinet/ip_ipsec_pxy.c"
  98 #include "netinet/ip_rpcb_pxy.c"
  99
 100 #if !defined(lint)
 101 static const char rcsid[] = "@(#)$Id$";
 102 #endif
 103
 104 #define AP_SESS_SIZE    53
 105
 106 static int ipf_proxy_fixseqack(fr_info_t *, ip_t *, ap_session_t *, int );
 107 static aproxy_t *ipf_proxy_create_clone(ipf_main_softc_t *, aproxy_t *);
 108
 109 typedef struct ipf_proxy_softc_s {
 110         int             ips_proxy_debug;
 111         int             ips_proxy_session_size;
 112         ap_session_t    **ips_sess_tab;
 113         ap_session_t    *ips_sess_list;
 114         aproxy_t        *ips_proxies;
 115         int             ips_init_run;
 116         ipftuneable_t   *ipf_proxy_tune;
 117 } ipf_proxy_softc_t;
 118
 119 static ipftuneable_t ipf_proxy_tuneables[] = {
 120         { { (void *)offsetof(ipf_proxy_softc_t, ips_proxy_debug) },
 121                 "proxy_debug",  0,      0x1f,
 122                 stsizeof(ipf_proxy_softc_t, ips_proxy_debug),
 123                 0,      NULL,   NULL },
 124         { { NULL },             NULL,                   0,      0,
 125                 0,
 126                 0,      NULL,   NULL}
 127 };
 128
 129 static  aproxy_t        *ap_proxylist = NULL;
 130 static  aproxy_t        ips_proxies[] = {
 131 #ifdef  IPF_FTP_PROXY
 132         { NULL, NULL, "ftp", (char)IPPROTO_TCP, 0, 0, 0,
 133           ipf_p_ftp_main_load, ipf_p_ftp_main_unload,
 134           ipf_p_ftp_soft_create, ipf_p_ftp_soft_destroy,
 135           NULL, NULL,
 136           ipf_p_ftp_new, ipf_p_ftp_del, ipf_p_ftp_in, ipf_p_ftp_out, NULL,
 137           NULL, NULL, NULL, NULL },
 138 #endif
 139 #ifdef  IPF_TFTP_PROXY
 140         { NULL, NULL, "tftp", (char)IPPROTO_UDP, 0, 0, 0,
 141           ipf_p_tftp_main_load, ipf_p_tftp_main_unload,
 142           ipf_p_tftp_soft_create, ipf_p_tftp_soft_destroy,
 143           NULL, NULL,
 144           ipf_p_tftp_new, ipf_p_tftp_del,
 145           ipf_p_tftp_in, ipf_p_tftp_out, NULL,
 146           NULL, NULL, NULL, NULL },
 147 #endif
 148 #ifdef  IPF_IRC_PROXY
 149         { NULL, NULL, "irc", (char)IPPROTO_TCP, 0, 0, 0,
 150           ipf_p_irc_main_load, ipf_p_irc_main_unload,
 151           NULL, NULL,
 152           NULL, NULL,
 153           ipf_p_irc_new, NULL, NULL, ipf_p_irc_out, NULL,
 154           NULL, NULL, NULL, NULL },
 155 #endif
 156 #ifdef  IPF_RCMD_PROXY
 157         { NULL, NULL, "rcmd", (char)IPPROTO_TCP, 0, 0, 0,
 158           ipf_p_rcmd_main_load, ipf_p_rcmd_main_unload,
 159           NULL, NULL,
 160           NULL, NULL,
 161           ipf_p_rcmd_new, ipf_p_rcmd_del,
 162           ipf_p_rcmd_in, ipf_p_rcmd_out, NULL,
 163           NULL, NULL, NULL, NULL },
 164 #endif
 165 #ifdef  IPF_RAUDIO_PROXY
 166         { NULL, NULL, "raudio", (char)IPPROTO_TCP, 0, 0, 0,
 167           ipf_p_raudio_main_load, ipf_p_raudio_main_unload,
 168           NULL, NULL,
 169           NULL, NULL,
 170           ipf_p_raudio_new, NULL, ipf_p_raudio_in, ipf_p_raudio_out, NULL,
 171           NULL, NULL, NULL, NULL },
 172 #endif
 173 #ifdef  IPF_MSNRPC_PROXY
 174         { NULL, NULL, "msnrpc", (char)IPPROTO_TCP, 0, 0, 0,
 175           ipf_p_msnrpc_init, ipf_p_msnrpc_fini,
 176           NULL, NULL,
 177           NULL, NULL,
 178           ipf_p_msnrpc_new, NULL, ipf_p_msnrpc_in, ipf_p_msnrpc_out, NULL,
 179           NULL, NULL, NULL, NULL },
 180 #endif
 181 #ifdef  IPF_NETBIOS_PROXY
 182         { NULL, NULL, "netbios", (char)IPPROTO_UDP, 0, 0, 0,
 183           ipf_p_netbios_main_load, ipf_p_netbios_main_unload,
 184           NULL, NULL,
 185           NULL, NULL,
 186           NULL, NULL, NULL, ipf_p_netbios_out, NULL,
 187           NULL, NULL, NULL, NULL },
 188 #endif
 189 #ifdef  IPF_IPSEC_PROXY
 190         { NULL, NULL, "ipsec", (char)IPPROTO_UDP, 0, 0, 0,
 191           NULL, NULL,
 192           ipf_p_ipsec_soft_create, ipf_p_ipsec_soft_destroy,
 193           ipf_p_ipsec_soft_init, ipf_p_ipsec_soft_fini,
 194           ipf_p_ipsec_new, ipf_p_ipsec_del,
 195           ipf_p_ipsec_inout, ipf_p_ipsec_inout, ipf_p_ipsec_match,
 196           NULL, NULL, NULL, NULL },
 197 #endif
 198 #ifdef  IPF_DNS_PROXY
 199         { NULL, NULL, "dns", (char)IPPROTO_UDP, 0, 0, 0,
 200           NULL, NULL,
 201           ipf_p_dns_soft_create, ipf_p_dns_soft_destroy,
 202           NULL, NULL,
 203           ipf_p_dns_new, ipf_p_ipsec_del,
 204           ipf_p_dns_inout, ipf_p_dns_inout, ipf_p_dns_match,
 205           ipf_p_dns_ctl, NULL, NULL, NULL },
 206 #endif
 207 #ifdef  IPF_PPTP_PROXY
 208         { NULL, NULL, "pptp", (char)IPPROTO_TCP, 0, 0, 0,
 209           ipf_p_pptp_main_load, ipf_p_pptp_main_unload,
 210           NULL, NULL,
 211           NULL, NULL,
 212           ipf_p_pptp_new, ipf_p_pptp_del,
 213           ipf_p_pptp_inout, ipf_p_pptp_inout, NULL,
 214           NULL, NULL, NULL, NULL },
 215 #endif
 216 #ifdef  IPF_RPCB_PROXY
 217 # ifndef _KERNEL
 218         { NULL, NULL, "rpcbt", (char)IPPROTO_TCP, 0, 0, 0,
 219           NULL, NULL,
 220           NULL, NULL,
 221           NULL, NULL,
 222           ipf_p_rpcb_new, ipf_p_rpcb_del,
 223           ipf_p_rpcb_in, ipf_p_rpcb_out, NULL,
 224           NULL, NULL, NULL, NULL },
 225 # endif
 226         { NULL, NULL, "rpcbu", (char)IPPROTO_UDP, 0, 0, 0,
 227           ipf_p_rpcb_main_load, ipf_p_rpcb_main_unload,
 228           NULL, NULL,
 229           NULL, NULL,
 230           ipf_p_rpcb_new, ipf_p_rpcb_del,
 231           ipf_p_rpcb_in, ipf_p_rpcb_out, NULL,
 232           NULL, NULL, NULL, NULL },
 233 #endif
 234         { NULL, NULL, "", '\0', 0, 0, 0,
 235           NULL, NULL,
 236           NULL, NULL,
 237           NULL, NULL,
 238           NULL, NULL,
 239           NULL, NULL, NULL,
 240           NULL, NULL, NULL, NULL }
 241 };
 242
 243
 244 /* ------------------------------------------------------------------------ */
 245 /* Function:    ipf_proxy_main_load                                         */
 246 /* Returns:     int    - 0 == success, else failure.                        */
 247 /* Parameters:  Nil                                                         */
 248 /*                                                                          */
 249 /* Initialise hook for kernel application proxies.                          */
 250 /* Call the initialise routine for all the compiled in kernel proxies.      */
 251 /* ------------------------------------------------------------------------ */
 252 int
 253 ipf_proxy_main_load(void)
 254 {
 255         aproxy_t *ap;
 256
 257         for (ap = ips_proxies; ap->apr_p; ap++) {
 258                 if (ap->apr_load != NULL)
 259                         (*ap->apr_load)();
 260         }
 261         return (0);
 262 }
 263
 264
 265 /* ------------------------------------------------------------------------ */
 266 /* Function:    ipf_proxy_main_unload                                       */
 267 /* Returns:     int - 0 == success, else failure.                           */
 268 /* Parameters:  Nil                                                         */
 269 /*                                                                          */
 270 /* Unload hook for kernel application proxies.                              */
 271 /* Call the finialise routine for all the compiled in kernel proxies.       */
 272 /* ------------------------------------------------------------------------ */
 273 int
 274 ipf_proxy_main_unload(void)
 275 {
 276         aproxy_t *ap;
 277
 278         for (ap = ips_proxies; ap->apr_p; ap++)
 279                 if (ap->apr_unload != NULL)
 280                         (*ap->apr_unload)();
 281         for (ap = ap_proxylist; ap; ap = ap->apr_next)
 282                 if (ap->apr_unload != NULL)
 283                         (*ap->apr_unload)();
 284
 285         return (0);
 286 }
 287
 288
 289 /* ------------------------------------------------------------------------ */
 290 /* Function:    ipf_proxy_soft_create                                       */
 291 /* Returns:     void *   -                                                  */
 292 /* Parameters:  softc(I) - pointer to soft context main structure           */
 293 /*                                                                          */
 294 /* Build the structure to hold all of the run time data to support proxies. */
 295 /* ------------------------------------------------------------------------ */
 296 void *
 297 ipf_proxy_soft_create(ipf_main_softc_t *softc)
 298 {
 299         ipf_proxy_softc_t *softp;
 300         aproxy_t *last;
 301         aproxy_t *apn;
 302         aproxy_t *ap;
 303
 304         KMALLOC(softp, ipf_proxy_softc_t *);
 305         if (softp == NULL)
 306                 return (softp);
 307
 308         bzero((char *)softp, sizeof(*softp));
 309
 310 #if defined(_KERNEL)
 311         softp->ips_proxy_debug = 0;
 312 #else
 313         softp->ips_proxy_debug = 2;
 314 #endif
 315         softp->ips_proxy_session_size = AP_SESS_SIZE;
 316
 317         softp->ipf_proxy_tune = ipf_tune_array_copy(softp,
 318                                                     sizeof(ipf_proxy_tuneables),
 319                                                     ipf_proxy_tuneables);
 320         if (softp->ipf_proxy_tune == NULL) {
 321                 ipf_proxy_soft_destroy(softc, softp);
 322                 return (NULL);
 323         }
 324         if (ipf_tune_array_link(softc, softp->ipf_proxy_tune) == -1) {
 325                 ipf_proxy_soft_destroy(softc, softp);
 326                 return (NULL);
 327         }
 328
 329         last = NULL;
 330         for (ap = ips_proxies; ap->apr_p; ap++) {
 331                 apn = ipf_proxy_create_clone(softc, ap);
 332                 if (apn == NULL)
 333                         goto failed;
 334                 if (last != NULL)
 335                         last->apr_next = apn;
 336                 else
 337                         softp->ips_proxies = apn;
 338                 last = apn;
 339         }
 340         for (ap = ips_proxies; ap != NULL; ap = ap->apr_next) {
 341                 apn = ipf_proxy_create_clone(softc, ap);
 342                 if (apn == NULL)
 343                         goto failed;
 344                 if (last != NULL)
 345                         last->apr_next = apn;
 346                 else
 347                         softp->ips_proxies = apn;
 348                 last = apn;
 349         }
 350
 351         return (softp);
 352 failed:
 353         ipf_proxy_soft_destroy(softc, softp);
 354         return (NULL);
 355 }
 356
 357
 358 /* ------------------------------------------------------------------------ */
 359 /* Function:    ipf_proxy_soft_create                                       */
 360 /* Returns:     void *   -                                                  */
 361 /* Parameters:  softc(I) - pointer to soft context main structure           */
 362 /*              orig(I)  - pointer to proxy definition to copy              */
 363 /*                                                                          */
 364 /* This function clones a proxy definition given by orig and returns a      */
 365 /* a pointer to that copy.                                                  */
 366 /* ------------------------------------------------------------------------ */
 367 static aproxy_t *
 368 ipf_proxy_create_clone(ipf_main_softc_t *softc, aproxy_t *orig)
 369 {
 370         aproxy_t *apn;
 371
 372         KMALLOC(apn, aproxy_t *);
 373         if (apn == NULL)
 374                 return (NULL);
 375
 376         bcopy((char *)orig, (char *)apn, sizeof(*apn));
 377         apn->apr_next = NULL;
 378         apn->apr_soft = NULL;
 379
 380         if (apn->apr_create != NULL) {
 381                 apn->apr_soft = (*apn->apr_create)(softc);
 382                 if (apn->apr_soft == NULL) {
 383                         KFREE(apn);
 384                         return (NULL);
 385                 }
 386         }
 387
 388         apn->apr_parent = orig;
 389         orig->apr_clones++;
 390
 391         return (apn);
 392 }
 393
 394
 395 /* ------------------------------------------------------------------------ */
 396 /* Function:    ipf_proxy_soft_create                                       */
 397 /* Returns:     int      - 0 == success, else failure.                      */
 398 /* Parameters:  softc(I) - pointer to soft context main structure           */
 399 /*              arg(I)   - pointer to proxy contect data                    */
 400 /*                                                                          */
 401 /* Initialise the proxy context and walk through each of the proxies and    */
 402 /* call its initialisation function. This allows for proxies to do any      */
 403 /* local setup prior to actual use.                                         */
 404 /* ------------------------------------------------------------------------ */
 405 int
 406 ipf_proxy_soft_init(ipf_main_softc_t *softc, void *arg)
 407 {
 408         ipf_proxy_softc_t *softp;
 409         aproxy_t *ap;
 410         u_int size;
 411         int err;
 412
 413         softp = arg;
 414         size = softp->ips_proxy_session_size * sizeof(ap_session_t *);
 415
 416         KMALLOCS(softp->ips_sess_tab, ap_session_t **, size);
 417
 418         if (softp->ips_sess_tab == NULL)
 419                 return (-1);
 420
 421         bzero(softp->ips_sess_tab, size);
 422
 423         for (ap = softp->ips_proxies; ap != NULL; ap = ap->apr_next) {
 424                 if (ap->apr_init != NULL) {
 425                         err = (*ap->apr_init)(softc, ap->apr_soft);
 426                         if (err != 0)
 427                                 return (-2);
 428                 }
 429         }
 430         softp->ips_init_run = 1;
 431
 432         return (0);
 433 }
 434
 435
 436 /* ------------------------------------------------------------------------ */
 437 /* Function:    ipf_proxy_soft_create                                       */
 438 /* Returns:     int      - 0 == success, else failure.                      */
 439 /* Parameters:  softc(I) - pointer to soft context main structure           */
 440 /*              arg(I)   - pointer to proxy contect data                    */
 441 /*                                                                          */
 442 /* This function should always succeed. It is responsible for ensuring that */
 443 /* the proxy context can be safely called when ipf_proxy_soft_destroy is    */
 444 /* called and suring all of the proxies have similarly been instructed.     */
 445 /* ------------------------------------------------------------------------ */
 446 int
 447 ipf_proxy_soft_fini(ipf_main_softc_t *softc, void *arg)
 448 {
 449         ipf_proxy_softc_t *softp = arg;
 450         aproxy_t *ap;
 451
 452         for (ap = softp->ips_proxies; ap != NULL; ap = ap->apr_next) {
 453                 if (ap->apr_fini != NULL) {
 454                         (*ap->apr_fini)(softc, ap->apr_soft);
 455                 }
 456         }
 457
 458         if (softp->ips_sess_tab != NULL) {
 459                 KFREES(softp->ips_sess_tab,
 460                        softp->ips_proxy_session_size * sizeof(ap_session_t *));
 461                 softp->ips_sess_tab = NULL;
 462         }
 463         softp->ips_init_run = 0;
 464
 465         return (0);
 466 }
 467
 468
 469 /* ------------------------------------------------------------------------ */
 470 /* Function:    ipf_proxy_soft_destroy                                      */
 471 /* Returns:     Nil                                                         */
 472 /* Parameters:  softc(I) - pointer to soft context main structure           */
 473 /*              arg(I)   - pointer to proxy contect data                    */
 474 /*                                                                          */
 475 /* Free up all of the local data structures allocated during creation.      */
 476 /* ------------------------------------------------------------------------ */
 477 void
 478 ipf_proxy_soft_destroy(ipf_main_softc_t *softc, void *arg)
 479 {
 480         ipf_proxy_softc_t *softp = arg;
 481         aproxy_t *ap;
 482
 483         while ((ap = softp->ips_proxies) != NULL) {
 484                 softp->ips_proxies = ap->apr_next;
 485                 if (ap->apr_destroy != NULL)
 486                         (*ap->apr_destroy)(softc, ap->apr_soft);
 487                 ap->apr_parent->apr_clones--;
 488                 KFREE(ap);
 489         }
 490
 491         if (softp->ipf_proxy_tune != NULL) {
 492                 ipf_tune_array_unlink(softc, softp->ipf_proxy_tune);
 493                 KFREES(softp->ipf_proxy_tune, sizeof(ipf_proxy_tuneables));
 494                 softp->ipf_proxy_tune = NULL;
 495         }
 496
 497         KFREE(softp);
 498 }
 499
 500
 501 /* ------------------------------------------------------------------------ */
 502 /* Function:    ipf_proxy_flush                                             */
 503 /* Returns:     Nil                                                         */
 504 /* Parameters:  arg(I)   - pointer to proxy contect data                    */
 505 /*              how(I)   - indicates the type of flush operation            */
 506 /*                                                                          */
 507 /* Walk through all of the proxies and pass on the flush command as either  */
 508 /* a flush or a clear.                                                      */
 509 /* ------------------------------------------------------------------------ */
 510 void
 511 ipf_proxy_flush(void *arg, int how)
 512 {
 513         ipf_proxy_softc_t *softp = arg;
 514         aproxy_t *ap;
 515
 516         switch (how)
 517         {
 518         case 0 :
 519                 for (ap = softp->ips_proxies; ap; ap = ap->apr_next)
 520                         if (ap->apr_flush != NULL)
 521                                 (*ap->apr_flush)(ap, how);
 522                 break;
 523         case 1 :
 524                 for (ap = softp->ips_proxies; ap; ap = ap->apr_next)
 525                         if (ap->apr_clear != NULL)
 526                                 (*ap->apr_clear)(ap);
 527                 break;
 528         default :
 529                 break;
 530         }
 531 }
 532
 533
 534 /* ------------------------------------------------------------------------ */
 535 /* Function:    ipf_proxy_add                                               */
 536 /* Returns:     int   - 0 == success, else failure.                         */
 537 /* Parameters:  ap(I) - pointer to proxy structure                          */
 538 /*                                                                          */
 539 /* Dynamically add a new kernel proxy.  Ensure that it is unique in the     */
 540 /* collection compiled in and dynamically added.                            */
 541 /* ------------------------------------------------------------------------ */
 542 int
 543 ipf_proxy_add(void *arg, aproxy_t *ap)
 544 {
 545         ipf_proxy_softc_t *softp = arg;
 546
 547         aproxy_t *a;
 548
 549         for (a = ips_proxies; a->apr_p; a++)
 550                 if ((a->apr_p == ap->apr_p) &&
 551                     !strncmp(a->apr_label, ap->apr_label,
 552                              sizeof(ap->apr_label))) {
 553                         if (softp->ips_proxy_debug & 0x01)
 554                                 printf("ipf_proxy_add: %s/%d present (B)\n",
 555                                        a->apr_label, a->apr_p);
 556                         return (-1);
 557                 }
 558
 559         for (a = ap_proxylist; (a != NULL); a = a->apr_next)
 560                 if ((a->apr_p == ap->apr_p) &&
 561                     !strncmp(a->apr_label, ap->apr_label,
 562                              sizeof(ap->apr_label))) {
 563                         if (softp->ips_proxy_debug & 0x01)
 564                                 printf("ipf_proxy_add: %s/%d present (D)\n",
 565                                        a->apr_label, a->apr_p);
 566                         return (-1);
 567                 }
 568         ap->apr_next = ap_proxylist;
 569         ap_proxylist = ap;
 570         if (ap->apr_load != NULL)
 571                 (*ap->apr_load)();
 572         return (0);
 573 }
 574
 575
 576 /* ------------------------------------------------------------------------ */
 577 /* Function:    ipf_proxy_ctl                                               */
 578 /* Returns:     int    - 0 == success, else error                           */
 579 /* Parameters:  softc(I) - pointer to soft context main structure           */
 580 /*              arg(I)   - pointer to proxy context                         */
 581 /*              ctl(I)   - pointer to proxy control structure               */
 582 /*                                                                          */
 583 /* Check to see if the proxy this control request has come through for      */
 584 /* exists, and if it does and it has a control function then invoke that    */
 585 /* control function.                                                        */
 586 /* ------------------------------------------------------------------------ */
 587 int
 588 ipf_proxy_ctl(ipf_main_softc_t *softc, void *arg, ap_ctl_t *ctl)
 589 {
 590         ipf_proxy_softc_t *softp = arg;
 591         aproxy_t *a;
 592         int error;
 593
 594         a = ipf_proxy_lookup(arg, ctl->apc_p, ctl->apc_label);
 595         if (a == NULL) {
 596                 if (softp->ips_proxy_debug & 0x01)
 597                         printf("ipf_proxy_ctl: can't find %s/%d\n",
 598                                 ctl->apc_label, ctl->apc_p);
 599                 IPFERROR(80001);
 600                 error = ESRCH;
 601         } else if (a->apr_ctl == NULL) {
 602                 if (softp->ips_proxy_debug & 0x01)
 603                         printf("ipf_proxy_ctl: no ctl function for %s/%d\n",
 604                                 ctl->apc_label, ctl->apc_p);
 605                 IPFERROR(80002);
 606                 error = ENXIO;
 607         } else {
 608                 error = (*a->apr_ctl)(softc, a->apr_soft, ctl);
 609                 if ((error != 0) && (softp->ips_proxy_debug & 0x02))
 610                         printf("ipf_proxy_ctl: %s/%d ctl error %d\n",
 611                                 a->apr_label, a->apr_p, error);
 612         }
 613         return (error);
 614 }
 615
 616
 617 /* ------------------------------------------------------------------------ */
 618 /* Function:    ipf_proxy_del                                               */
 619 /* Returns:     int   - 0 == success, else failure.                         */
 620 /* Parameters:  ap(I) - pointer to proxy structure                          */
 621 /*                                                                          */
 622 /* Delete a proxy that has been added dynamically from those available.     */
 623 /* If it is in use, return 1 (do not destroy NOW), not in use 0 or -1       */
 624 /* if it cannot be matched.                                                 */
 625 /* ------------------------------------------------------------------------ */
 626 int
 627 ipf_proxy_del(aproxy_t *ap)
 628 {
 629         aproxy_t *a, **app;
 630
 631         for (app = &ap_proxylist; ((a = *app) != NULL); app = &a->apr_next) {
 632                 if (a == ap) {
 633                         a->apr_flags |= APR_DELETE;
 634                         if (ap->apr_ref == 0 && ap->apr_clones == 0) {
 635                                 *app = a->apr_next;
 636                                 return (0);
 637                         }
 638                         return (1);
 639                 }
 640         }
 641
 642         return (-1);
 643 }
 644
 645
 646 /* ------------------------------------------------------------------------ */
 647 /* Function:    ipf_proxy_ok                                                */
 648 /* Returns:     int    - 1 == good match else not.                          */
 649 /* Parameters:  fin(I) - pointer to packet information                      */
 650 /*              tcp(I) - pointer to TCP/UDP header                          */
 651 /*              nat(I) - pointer to current NAT session                     */
 652 /*                                                                          */
 653 /* This function extends the NAT matching to ensure that a packet that has  */
 654 /* arrived matches the proxy information attached to the NAT rule. Notably, */
 655 /* if the proxy is scheduled to be deleted then packets will not match the  */
 656 /* rule even if the rule is still active.                                   */
 657 /* ------------------------------------------------------------------------ */
 658 int
 659 ipf_proxy_ok(fr_info_t *fin, tcphdr_t *tcp, ipnat_t *np)
 660 {
 661         aproxy_t *apr = np->in_apr;
 662         u_short dport = np->in_odport;
 663
 664         if ((apr == NULL) || (apr->apr_flags & APR_DELETE) ||
 665             (fin->fin_p != apr->apr_p))
 666                 return (0);
 667         if ((tcp == NULL) && dport)
 668                 return (0);
 669         return (1);
 670 }
 671
 672
 673 /* ------------------------------------------------------------------------ */
 674 /* Function:    ipf_proxy_ioctl                                             */
 675 /* Returns:     int    - 0 == success, else error                           */
 676 /* Parameters:  softc(I) - pointer to soft context main structure           */
 677 /*              data(I)  - pointer to ioctl data                            */
 678 /*              cmd(I)   - ioctl command                                    */
 679 /*              mode(I)  - mode bits for device                             */
 680 /*              ctx(I)   - pointer to context information                   */
 681 /*                                                                          */
 682 /* ------------------------------------------------------------------------ */
 683 int
 684 ipf_proxy_ioctl(ipf_main_softc_t *softc, caddr_t data, ioctlcmd_t cmd,
 685         int mode, void *ctx)
 686 {
 687         ap_ctl_t ctl;
 688         caddr_t ptr;
 689         int error;
 690
 691         mode = mode;    /* LINT */
 692
 693         switch (cmd)
 694         {
 695         case SIOCPROXY :
 696                 error = ipf_inobj(softc, data, NULL, &ctl, IPFOBJ_PROXYCTL);
 697                 if (error != 0) {
 698                         return (error);
 699                 }
 700                 ptr = NULL;
 701
 702                 if (ctl.apc_dsize > 0) {
 703                         KMALLOCS(ptr, caddr_t, ctl.apc_dsize);
 704                         if (ptr == NULL) {
 705                                 IPFERROR(80003);
 706                                 error = ENOMEM;
 707                         } else {
 708                                 error = copyinptr(softc, ctl.apc_data, ptr,
 709                                                   ctl.apc_dsize);
 710                                 if (error == 0)
 711                                         ctl.apc_data = ptr;
 712                         }
 713                 } else {
 714                         ctl.apc_data = NULL;
 715                         error = 0;
 716                 }
 717
 718                 if (error == 0)
 719                         error = ipf_proxy_ctl(softc, softc->ipf_proxy_soft,
 720                                               &ctl);
 721
 722                 if ((error != 0) && (ptr != NULL)) {
 723                         KFREES(ptr, ctl.apc_dsize);
 724                 }
 725                 break;
 726
 727         default :
 728                 IPFERROR(80004);
 729                 error = EINVAL;
 730         }
 731         return (error);
 732 }
 733
 734
 735 /* ------------------------------------------------------------------------ */
 736 /* Function:    ipf_proxy_match                                             */
 737 /* Returns:     int    - 0 == success, else error                           */
 738 /* Parameters:  fin(I) - pointer to packet information                      */
 739 /*              nat(I) - pointer to current NAT session                     */
 740 /*                                                                          */
 741 /* If a proxy has a match function, call that to do extended packet         */
 742 /* matching. Whilst other parts of the NAT code are rather lenient when it  */
 743 /* comes to the quality of the packet that it will transform, the proxy     */
 744 /* matching is not because they need to work with data, not just headers.   */
 745 /* ------------------------------------------------------------------------ */
 746 int
 747 ipf_proxy_match(fr_info_t *fin, nat_t *nat)
 748 {
 749         ipf_main_softc_t *softc = fin->fin_main_soft;
 750         ipf_proxy_softc_t *softp = softc->ipf_proxy_soft;
 751         aproxy_t *apr;
 752         ipnat_t *ipn;
 753         int result;
 754
 755         ipn = nat->nat_ptr;
 756         if (softp->ips_proxy_debug & 0x04)
 757                 printf("ipf_proxy_match(%lx,%lx) aps %lx ptr %lx\n",
 758                         (u_long)fin, (u_long)nat, (u_long)nat->nat_aps,
 759                         (u_long)ipn);
 760
 761         if ((fin->fin_flx & (FI_SHORT|FI_BAD)) != 0) {
 762                 if (softp->ips_proxy_debug & 0x08)
 763                         printf("ipf_proxy_match: flx 0x%x (BAD|SHORT)\n",
 764                                 fin->fin_flx);
 765                 return (-1);
 766         }
 767
 768         apr = ipn->in_apr;
 769         if ((apr == NULL) || (apr->apr_flags & APR_DELETE)) {
 770                 if (softp->ips_proxy_debug & 0x08)
 771                         printf("ipf_proxy_match:apr %lx apr_flags 0x%x\n",
 772                                 (u_long)apr, apr ? apr->apr_flags : 0);
 773                 return (-1);
 774         }
 775
 776         if (apr->apr_match != NULL) {
 777                 result = (*apr->apr_match)(fin, nat->nat_aps, nat);
 778                 if (result != 0) {
 779                         if (softp->ips_proxy_debug & 0x08)
 780                                 printf("ipf_proxy_match: result %d\n", result);
 781                         return (-1);
 782                 }
 783         }
 784         return (0);
 785 }
 786
 787
 788 /* ------------------------------------------------------------------------ */
 789 /* Function:    ipf_proxy_new                                               */
 790 /* Returns:     int    - 0 == success, else error                           */
 791 /* Parameters:  fin(I) - pointer to packet information                      */
 792 /*              nat(I) - pointer to current NAT session                     */
 793 /*                                                                          */
 794 /* Allocate a new application proxy structure and fill it in with the       */
 795 /* relevant details.  call the init function once complete, prior to        */
 796 /* returning.                                                               */
 797 /* ------------------------------------------------------------------------ */
 798 int
 799 ipf_proxy_new(fr_info_t *fin, nat_t *nat)
 800 {
 801         ipf_main_softc_t *softc = fin->fin_main_soft;
 802         ipf_proxy_softc_t *softp = softc->ipf_proxy_soft;
 803         register ap_session_t *aps;
 804         aproxy_t *apr;
 805
 806         if (softp->ips_proxy_debug & 0x04)
 807                 printf("ipf_proxy_new(%lx,%lx) \n", (u_long)fin, (u_long)nat);
 808
 809         if ((nat->nat_ptr == NULL) || (nat->nat_aps != NULL)) {
 810                 if (softp->ips_proxy_debug & 0x08)
 811                         printf("ipf_proxy_new: nat_ptr %lx nat_aps %lx\n",
 812                                 (u_long)nat->nat_ptr, (u_long)nat->nat_aps);
 813                 return (-1);
 814         }
 815
 816         apr = nat->nat_ptr->in_apr;
 817
 818         if ((apr->apr_flags & APR_DELETE) ||
 819             (fin->fin_p != apr->apr_p)) {
 820                 if (softp->ips_proxy_debug & 0x08)
 821                         printf("ipf_proxy_new: apr_flags 0x%x p %d/%d\n",
 822                                 apr->apr_flags, fin->fin_p, apr->apr_p);
 823                 return (-1);
 824         }
 825
 826         KMALLOC(aps, ap_session_t *);
 827         if (!aps) {
 828                 if (softp->ips_proxy_debug & 0x08)
 829                         printf("ipf_proxy_new: malloc failed (%lu)\n",
 830                                 (u_long)sizeof(ap_session_t));
 831                 return (-1);
 832         }
 833
 834         bzero((char *)aps, sizeof(*aps));
 835         aps->aps_data = NULL;
 836         aps->aps_apr = apr;
 837         aps->aps_psiz = 0;
 838         if (apr->apr_new != NULL)
 839                 if ((*apr->apr_new)(apr->apr_soft, fin, aps, nat) == -1) {
 840                         if ((aps->aps_data != NULL) && (aps->aps_psiz != 0)) {
 841                                 KFREES(aps->aps_data, aps->aps_psiz);
 842                         }
 843                         KFREE(aps);
 844                         if (softp->ips_proxy_debug & 0x08)
 845                                 printf("ipf_proxy_new: new(%lx) failed\n",
 846                                         (u_long)apr->apr_new);
 847                         return (-1);
 848                 }
 849         aps->aps_nat = nat;
 850         aps->aps_next = softp->ips_sess_list;
 851         softp->ips_sess_list = aps;
 852         nat->nat_aps = aps;
 853
 854         return (0);
 855 }
 856
 857
 858 /* ------------------------------------------------------------------------ */
 859 /* Function:    ipf_proxy_check                                             */
 860 /* Returns:     int - -1 == error, 1 == success                             */
 861 /* Parameters:  fin(I) - pointer to packet information                      */
 862 /*              nat(I) - pointer to current NAT session                     */
 863 /*                                                                          */
 864 /* Check to see if a packet should be passed through an active proxy        */
 865 /* routine if one has been setup for it.  We don't need to check the        */
 866 /* checksum here if IPFILTER_CKSUM is defined because if it is, a failed    */
 867 /* check causes FI_BAD to be set.                                           */
 868 /* ------------------------------------------------------------------------ */
 869 int
 870 ipf_proxy_check(fr_info_t *fin, nat_t *nat)
 871 {
 872         ipf_main_softc_t *softc = fin->fin_main_soft;
 873         ipf_proxy_softc_t *softp = softc->ipf_proxy_soft;
 874 #if SOLARIS && defined(_KERNEL) && defined(ICK_VALID)
 875         mb_t *m;
 876 #endif
 877         tcphdr_t *tcp = NULL;
 878         udphdr_t *udp = NULL;
 879         ap_session_t *aps;
 880         aproxy_t *apr;
 881         short adjlen;
 882         int dosum;
 883         ip_t *ip;
 884         short rv;
 885         int err;
 886 #if !defined(_KERNEL) || SOLARIS || defined(__FreeBSD__)
 887         u_32_t s1, s2, sd;
 888 #endif
 889
 890         if (fin->fin_flx & FI_BAD) {
 891                 if (softp->ips_proxy_debug & 0x08)
 892                         printf("ipf_proxy_check: flx 0x%x (BAD)\n",
 893                                fin->fin_flx);
 894                 return (-1);
 895         }
 896
 897 #ifndef IPFILTER_CKSUM
 898         if ((fin->fin_out == 0) && (ipf_checkl4sum(fin) == -1)) {
 899                 if (softp->ips_proxy_debug & 0x08)
 900                         printf("ipf_proxy_check: l4 checksum failure %d\n",
 901                                 fin->fin_p);
 902                 if (fin->fin_p == IPPROTO_TCP)
 903                         softc->ipf_stats[fin->fin_out].fr_tcpbad++;
 904                 return (-1);
 905         }
 906 #endif
 907
 908         aps = nat->nat_aps;
 909         if (aps != NULL) {
 910                 /*
 911                  * If there is data in this packet to be proxied then try and
 912                  * get it all into the one buffer, else drop it.
 913                  */
 914 #if SOLARIS || defined(HAVE_M_PULLDOWN)
 915                 if ((fin->fin_dlen > 0) && !(fin->fin_flx & FI_COALESCE))
 916                         if (ipf_coalesce(fin) == -1) {
 917                                 if (softp->ips_proxy_debug & 0x08)
 918                                         printf("ipf_proxy_check: %s %x\n",
 919                                                "coalesce failed", fin->fin_flx);
 920                                 return (-1);
 921                         }
 922 #endif
 923                 ip = fin->fin_ip;
 924                 if (fin->fin_cksum > FI_CK_SUMOK)
 925                         dosum = 0;
 926                 else
 927                         dosum = 1;
 928
 929                 switch (fin->fin_p)
 930                 {
 931                 case IPPROTO_TCP :
 932                         tcp = (tcphdr_t *)fin->fin_dp;
 933 #if SOLARIS && defined(_KERNEL) && defined(ICK_VALID)
 934                         m = fin->fin_qfm;
 935                         if (dohwcksum && (m->b_ick_flag == ICK_VALID))
 936                                 dosum = 0;
 937 #endif
 938                         break;
 939                 case IPPROTO_UDP :
 940                         udp = (udphdr_t *)fin->fin_dp;
 941                         break;
 942                 default :
 943                         break;
 944                 }
 945
 946                 apr = aps->aps_apr;
 947                 err = 0;
 948                 if (fin->fin_out != 0) {
 949                         if (apr->apr_outpkt != NULL)
 950                                 err = (*apr->apr_outpkt)(apr->apr_soft, fin,
 951                                                          aps, nat);
 952                 } else {
 953                         if (apr->apr_inpkt != NULL)
 954                                 err = (*apr->apr_inpkt)(apr->apr_soft, fin,
 955                                                         aps, nat);
 956                 }
 957
 958                 rv = APR_EXIT(err);
 959                 if (((softp->ips_proxy_debug & 0x08) && (rv != 0)) ||
 960                     (softp->ips_proxy_debug & 0x04))
 961                         printf("ipf_proxy_check: out %d err %x rv %d\n",
 962                                 fin->fin_out, err, rv);
 963                 if (rv == 1)
 964                         return (-1);
 965
 966                 if (rv == 2) {
 967                         ipf_proxy_deref(apr);
 968                         nat->nat_aps = NULL;
 969                         return (-1);
 970                 }
 971
 972                 /*
 973                  * If err != 0 then the data size of the packet has changed
 974                  * so we need to recalculate the header checksums for the
 975                  * packet.
 976                  */
 977                 adjlen = APR_INC(err);
 978 #if !defined(_KERNEL) || SOLARIS || defined(__FreeBSD__)
 979                 s1 = LONG_SUM(fin->fin_plen - adjlen);
 980                 s2 = LONG_SUM(fin->fin_plen);
 981                 CALC_SUMD(s1, s2, sd);
 982                 if ((err != 0) && (fin->fin_cksum < FI_CK_L4PART) &&
 983                     fin->fin_v == 4)
 984                         ipf_fix_outcksum(0, &ip->ip_sum, sd, 0);
 985 #endif
 986                 if (fin->fin_flx & FI_DOCKSUM)
 987                         dosum = 1;
 988
 989                 /*
 990                  * For TCP packets, we may need to adjust the sequence and
 991                  * acknowledgement numbers to reflect changes in size of the
 992                  * data stream.
 993                  *
 994                  * For both TCP and UDP, recalculate the layer 4 checksum,
 995                  * regardless, as we can't tell (here) if data has been
 996                  * changed or not.
 997                  */
 998                 if (tcp != NULL) {
 999                         err = ipf_proxy_fixseqack(fin, ip, aps, adjlen);
1000                         if (fin->fin_cksum == FI_CK_L4PART) {
1001                                 u_short sum = ntohs(tcp->th_sum);
1002                                 sum += adjlen;
1003                                 tcp->th_sum = htons(sum);
1004                         } else if (fin->fin_cksum < FI_CK_L4PART) {
1005                                 tcp->th_sum = fr_cksum(fin, ip,
1006                                                        IPPROTO_TCP, tcp);
1007                         }
1008                 } else if ((udp != NULL) && (udp->uh_sum != 0)) {
1009                         if (fin->fin_cksum == FI_CK_L4PART) {
1010                                 u_short sum = ntohs(udp->uh_sum);
1011                                 sum += adjlen;
1012                                 udp->uh_sum = htons(sum);
1013                         } else if (dosum) {
1014                                 udp->uh_sum = fr_cksum(fin, ip,
1015                                                        IPPROTO_UDP, udp);
1016                         }
1017                 }
1018                 aps->aps_bytes += fin->fin_plen;
1019                 aps->aps_pkts++;
1020         }
1021         return (1);
1022 }
1023
1024
1025 /* ------------------------------------------------------------------------ */
1026 /* Function:    ipf_proxy_lookup                                            */
1027 /* Returns:     int - -1 == error, 0 == success                             */
1028 /* Parameters:  arg(I)  - pointer to proxy context information              */
1029 /*              pr(I)   - protocol number for proxy                         */
1030 /*              name(I) - proxy name                                        */
1031 /*                                                                          */
1032 /* Search for a proxy by the protocol being used and by its name.           */
1033 /* ------------------------------------------------------------------------ */
1034 aproxy_t *
1035 ipf_proxy_lookup(void *arg, u_int pr, char *name)
1036 {
1037         ipf_proxy_softc_t *softp = arg;
1038         aproxy_t *ap;
1039
1040         if (softp->ips_proxy_debug & 0x04)
1041                 printf("ipf_proxy_lookup(%d,%s)\n", pr, name);
1042
1043         for (ap = softp->ips_proxies; ap != NULL; ap = ap->apr_next)
1044                 if ((ap->apr_p == pr) &&
1045                     !strncmp(name, ap->apr_label, sizeof(ap->apr_label))) {
1046                         ap->apr_ref++;
1047                         return (ap);
1048                 }
1049
1050         if (softp->ips_proxy_debug & 0x08)
1051                 printf("ipf_proxy_lookup: failed for %d/%s\n", pr, name);
1052         return (NULL);
1053 }
1054
1055
1056 /* ------------------------------------------------------------------------ */
1057 /* Function:    ipf_proxy_deref                                             */
1058 /* Returns:     Nil                                                         */
1059 /* Parameters:  ap(I) - pointer to proxy structure                          */
1060 /*                                                                          */
1061 /* Drop the reference counter associated with the proxy.                    */
1062 /* ------------------------------------------------------------------------ */
1063 void
1064 ipf_proxy_deref(aproxy_t *ap)
1065 {
1066         ap->apr_ref--;
1067 }
1068
1069
1070 /* ------------------------------------------------------------------------ */
1071 /* Function:    ipf_proxy_free                                              */
1072 /* Returns:     Nil                                                         */
1073 /* Parameters:  softc(I) - pointer to soft context main structure           */
1074 /*              aps(I)   - pointer to current proxy session                 */
1075 /* Locks Held:  ipf_nat_new, ipf_nat(W)                                     */
1076 /*                                                                          */
1077 /* Free up proxy session information allocated to be used with a NAT        */
1078 /* session.                                                                 */
1079 /* ------------------------------------------------------------------------ */
1080 void
1081 ipf_proxy_free(ipf_main_softc_t *softc, ap_session_t *aps)
1082 {
1083         ipf_proxy_softc_t *softp = softc->ipf_proxy_soft;
1084         ap_session_t *a, **ap;
1085         aproxy_t *apr;
1086
1087         if (!aps)
1088                 return;
1089
1090         for (ap = &softp->ips_sess_list; ((a = *ap) != NULL); ap = &a->aps_next)
1091                 if (a == aps) {
1092                         *ap = a->aps_next;
1093                         break;
1094                 }
1095
1096         apr = aps->aps_apr;
1097         if ((apr != NULL) && (apr->apr_del != NULL))
1098                 (*apr->apr_del)(softc, aps);
1099
1100         if ((aps->aps_data != NULL) && (aps->aps_psiz != 0))
1101                 KFREES(aps->aps_data, aps->aps_psiz);
1102         KFREE(aps);
1103 }
1104
1105
1106 /* ------------------------------------------------------------------------ */
1107 /* Function:    ipf_proxy_fixseqack                                         */
1108 /* Returns:     int    - 2 if TCP ack/seq is changed, else 0                */
1109 /* Parameters:  fin(I) - pointer to packet information                      */
1110 /*              ip(I)  - pointer to IP header                               */
1111 /*              nat(I) - pointer to current NAT session                     */
1112 /*              inc(I) - delta to apply to TCP sequence numbering           */
1113 /*                                                                          */
1114 /* Adjust the TCP sequence/acknowledge numbers in the TCP header based on   */
1115 /* whether or not the new header is past the point at which an adjustment   */
1116 /* occurred. This might happen because of (say) an FTP string being changed */
1117 /* and the new string being a different length to the old.                  */
1118 /* ------------------------------------------------------------------------ */
1119 static int
1120 ipf_proxy_fixseqack(fr_info_t *fin, ip_t *ip, ap_session_t *aps, int inc)
1121 {
1122         ipf_main_softc_t *softc = fin->fin_main_soft;
1123         ipf_proxy_softc_t *softp = softc->ipf_proxy_soft;
1124         int sel, ch = 0, out, nlen;
1125         u_32_t seq1, seq2;
1126         tcphdr_t *tcp;
1127         short inc2;
1128
1129         tcp = (tcphdr_t *)fin->fin_dp;
1130         out = fin->fin_out;
1131         /*
1132          * ip_len has already been adjusted by 'inc'.
1133          */
1134         nlen = fin->fin_dlen;
1135         nlen -= (TCP_OFF(tcp) << 2);
1136
1137         inc2 = inc;
1138         inc = (int)inc2;
1139
1140         if (out != 0) {
1141                 seq1 = (u_32_t)ntohl(tcp->th_seq);
1142                 sel = aps->aps_sel[out];
1143
1144                 /* switch to other set ? */
1145                 if ((aps->aps_seqmin[!sel] > aps->aps_seqmin[sel]) &&
1146                     (seq1 > aps->aps_seqmin[!sel])) {
1147                         if (softp->ips_proxy_debug & 0x10)
1148                                 printf("proxy out switch set seq %d -> %d %x > %x\n",
1149                                         sel, !sel, seq1,
1150                                         aps->aps_seqmin[!sel]);
1151                         sel = aps->aps_sel[out] = !sel;
1152                 }
1153
1154                 if (aps->aps_seqoff[sel]) {
1155                         seq2 = aps->aps_seqmin[sel] - aps->aps_seqoff[sel];
1156                         if (seq1 > seq2) {
1157                                 seq2 = aps->aps_seqoff[sel];
1158                                 seq1 += seq2;
1159                                 tcp->th_seq = htonl(seq1);
1160                                 ch = 1;
1161                         }
1162                 }
1163
1164                 if (inc && (seq1 > aps->aps_seqmin[!sel])) {
1165                         aps->aps_seqmin[sel] = seq1 + nlen - 1;
1166                         aps->aps_seqoff[sel] = aps->aps_seqoff[sel] + inc;
1167                         if (softp->ips_proxy_debug & 0x10)
1168                                 printf("proxy seq set %d at %x to %d + %d\n",
1169                                         sel, aps->aps_seqmin[sel],
1170                                         aps->aps_seqoff[sel], inc);
1171                 }
1172
1173                 /***/
1174
1175                 seq1 = ntohl(tcp->th_ack);
1176                 sel = aps->aps_sel[1 - out];
1177
1178                 /* switch to other set ? */
1179                 if ((aps->aps_ackmin[!sel] > aps->aps_ackmin[sel]) &&
1180                     (seq1 > aps->aps_ackmin[!sel])) {
1181                         if (softp->ips_proxy_debug & 0x10)
1182                                 printf("proxy out switch set ack %d -> %d %x > %x\n",
1183                                         sel, !sel, seq1,
1184                                         aps->aps_ackmin[!sel]);
1185                         sel = aps->aps_sel[1 - out] = !sel;
1186                 }
1187
1188                 if (aps->aps_ackoff[sel] && (seq1 > aps->aps_ackmin[sel])) {
1189                         seq2 = aps->aps_ackoff[sel];
1190                         tcp->th_ack = htonl(seq1 - seq2);
1191                         ch = 1;
1192                 }
1193         } else {
1194                 seq1 = ntohl(tcp->th_seq);
1195                 sel = aps->aps_sel[out];
1196
1197                 /* switch to other set ? */
1198                 if ((aps->aps_ackmin[!sel] > aps->aps_ackmin[sel]) &&
1199                     (seq1 > aps->aps_ackmin[!sel])) {
1200                         if (softp->ips_proxy_debug & 0x10)
1201                                 printf("proxy in switch set ack %d -> %d %x > %x\n",
1202                                         sel, !sel, seq1, aps->aps_ackmin[!sel]);
1203                         sel = aps->aps_sel[out] = !sel;
1204                 }
1205
1206                 if (aps->aps_ackoff[sel]) {
1207                         seq2 = aps->aps_ackmin[sel] - aps->aps_ackoff[sel];
1208                         if (seq1 > seq2) {
1209                                 seq2 = aps->aps_ackoff[sel];
1210                                 seq1 += seq2;
1211                                 tcp->th_seq = htonl(seq1);
1212                                 ch = 1;
1213                         }
1214                 }
1215
1216                 if (inc && (seq1 > aps->aps_ackmin[!sel])) {
1217                         aps->aps_ackmin[!sel] = seq1 + nlen - 1;
1218                         aps->aps_ackoff[!sel] = aps->aps_ackoff[sel] + inc;
1219
1220                         if (softp->ips_proxy_debug & 0x10)
1221                                 printf("proxy ack set %d at %x to %d + %d\n",
1222                                         !sel, aps->aps_seqmin[!sel],
1223                                         aps->aps_seqoff[sel], inc);
1224                 }
1225
1226                 /***/
1227
1228                 seq1 = ntohl(tcp->th_ack);
1229                 sel = aps->aps_sel[1 - out];
1230
1231                 /* switch to other set ? */
1232                 if ((aps->aps_seqmin[!sel] > aps->aps_seqmin[sel]) &&
1233                     (seq1 > aps->aps_seqmin[!sel])) {
1234                         if (softp->ips_proxy_debug & 0x10)
1235                                 printf("proxy in switch set seq %d -> %d %x > %x\n",
1236                                         sel, !sel, seq1, aps->aps_seqmin[!sel]);
1237                         sel = aps->aps_sel[1 - out] = !sel;
1238                 }
1239
1240                 if (aps->aps_seqoff[sel] != 0) {
1241                         if (softp->ips_proxy_debug & 0x10)
1242                                 printf("sel %d seqoff %d seq1 %x seqmin %x\n",
1243                                         sel, aps->aps_seqoff[sel], seq1,
1244                                         aps->aps_seqmin[sel]);
1245                         if (seq1 > aps->aps_seqmin[sel]) {
1246                                 seq2 = aps->aps_seqoff[sel];
1247                                 tcp->th_ack = htonl(seq1 - seq2);
1248                                 ch = 1;
1249                         }
1250                 }
1251         }
1252
1253         if (softp->ips_proxy_debug & 0x10)
1254                 printf("ipf_proxy_fixseqack: seq %u ack %u\n",
1255                         (u_32_t)ntohl(tcp->th_seq), (u_32_t)ntohl(tcp->th_ack));
1256         return (ch ? 2 : 0);
1257 }
1258
1259
1260 /* ------------------------------------------------------------------------ */
1261 /* Function:    ipf_proxy_rule_rev                                          */
1262 /* Returns:     ipnat_t * - NULL = failure, else pointer to new rule        */
1263 /* Parameters:  nat(I) - pointer to NAT session to create rule from         */
1264 /*                                                                          */
1265 /* This function creates a NAT rule that is based upon the reverse packet   */
1266 /* flow associated with this NAT session. Thus if this NAT session was      */
1267 /* created with a map rule then this function will create a rdr rule.       */
1268 /* Only address fields and network interfaces are assigned in this function */
1269 /* and the address fields are formed such that an exact is required. If the */
1270 /* original rule had a netmask, that is not replicated here not is it       */
1271 /* desired. The ultimate goal here is to create a NAT rule to support a NAT */
1272 /* session being created that does not have a user configured rule. The     */
1273 /* classic example is supporting the FTP proxy, where a data channel needs  */
1274 /* to be setup, based on the addresses used for the control connection. In  */
1275 /* that case, this function is used to handle creating NAT rules to support */
1276 /* data connections with the PORT and EPRT commands.                        */
1277 /* ------------------------------------------------------------------------ */
1278 ipnat_t *
1279 ipf_proxy_rule_rev(nat_t *nat)
1280 {
1281         ipnat_t *old;
1282         ipnat_t *ipn;
1283         int size;
1284
1285         old = nat->nat_ptr;
1286         size = old->in_size;
1287
1288         KMALLOCS(ipn, ipnat_t *, size);
1289         if (ipn == NULL)
1290                 return (NULL);
1291
1292         bzero((char *)ipn, size);
1293
1294         ipn->in_use = 1;
1295         ipn->in_hits = 1;
1296         ipn->in_ippip = 1;
1297         ipn->in_apr = NULL;
1298         ipn->in_size = size;
1299         ipn->in_pr[0] = old->in_pr[1];
1300         ipn->in_pr[1] = old->in_pr[0];
1301         ipn->in_v[0] = old->in_v[1];
1302         ipn->in_v[1] = old->in_v[0];
1303         ipn->in_ifps[0] = old->in_ifps[1];
1304         ipn->in_ifps[1] = old->in_ifps[0];
1305         ipn->in_flags = (old->in_flags | IPN_PROXYRULE);
1306
1307         ipn->in_nsrcip6 = nat->nat_odst6;
1308         ipn->in_osrcip6 = nat->nat_ndst6;
1309
1310         if ((old->in_redir & NAT_REDIRECT) != 0) {
1311                 ipn->in_redir = NAT_MAP;
1312                 if (ipn->in_v[0] == 4) {
1313                         ipn->in_snip = ntohl(nat->nat_odstaddr);
1314                         ipn->in_dnip = ntohl(nat->nat_nsrcaddr);
1315 #ifdef USE_INET6
1316                 } else {
1317                         ipn->in_snip6 = nat->nat_odst6;
1318                         ipn->in_dnip6 = nat->nat_nsrc6;
1319 #endif
1320                 }
1321                 ipn->in_ndstip6 = nat->nat_nsrc6;
1322                 ipn->in_odstip6 = nat->nat_osrc6;
1323         } else {
1324                 ipn->in_redir = NAT_REDIRECT;
1325                 if (ipn->in_v[0] == 4) {
1326                         ipn->in_snip = ntohl(nat->nat_odstaddr);
1327                         ipn->in_dnip = ntohl(nat->nat_osrcaddr);
1328 #ifdef USE_INET6
1329                 } else {
1330                         ipn->in_snip6 = nat->nat_odst6;
1331                         ipn->in_dnip6 = nat->nat_osrc6;
1332 #endif
1333                 }
1334                 ipn->in_ndstip6 = nat->nat_osrc6;
1335                 ipn->in_odstip6 = nat->nat_nsrc6;
1336         }
1337
1338         IP6_SETONES(&ipn->in_osrcmsk6);
1339         IP6_SETONES(&ipn->in_nsrcmsk6);
1340         IP6_SETONES(&ipn->in_odstmsk6);
1341         IP6_SETONES(&ipn->in_ndstmsk6);
1342
1343         ipn->in_namelen = old->in_namelen;
1344         ipn->in_ifnames[0] = old->in_ifnames[1];
1345         ipn->in_ifnames[1] = old->in_ifnames[0];
1346         bcopy(old->in_names, ipn->in_names, ipn->in_namelen);
1347         MUTEX_INIT(&ipn->in_lock, "ipnat rev rule lock");
1348
1349         return (ipn);
1350 }
1351
1352
1353 /* ------------------------------------------------------------------------ */
1354 /* Function:    ipf_proxy_rule_fwd                                          */
1355 /* Returns:     ipnat_t * - NULL = failure, else pointer to new rule        */
1356 /* Parameters:  nat(I) - pointer to NAT session to create rule from         */
1357 /*                                                                          */
1358 /* The purpose and rationale of this function is much the same as the above */
1359 /* function, ipf_proxy_rule_rev, except that a rule is created that matches */
1360 /* the same direction as that of the existing NAT session. Thus if this NAT */
1361 /* session was created with a map rule then this function will also create  */
1362 /* a data structure to represent a map rule. Whereas ipf_proxy_rule_rev is  */
1363 /* used to support PORT/EPRT, this function supports PASV/EPSV.             */
1364 /* ------------------------------------------------------------------------ */
1365 ipnat_t *
1366 ipf_proxy_rule_fwd(nat_t *nat)
1367 {
1368         ipnat_t *old;
1369         ipnat_t *ipn;
1370         int size;
1371
1372         old = nat->nat_ptr;
1373         size = old->in_size;
1374
1375         KMALLOCS(ipn, ipnat_t *, size);
1376         if (ipn == NULL)
1377                 return (NULL);
1378
1379         bzero((char *)ipn, size);
1380
1381         ipn->in_use = 1;
1382         ipn->in_hits = 1;
1383         ipn->in_ippip = 1;
1384         ipn->in_apr = NULL;
1385         ipn->in_size = size;
1386         ipn->in_pr[0] = old->in_pr[0];
1387         ipn->in_pr[1] = old->in_pr[1];
1388         ipn->in_v[0] = old->in_v[0];
1389         ipn->in_v[1] = old->in_v[1];
1390         ipn->in_ifps[0] = nat->nat_ifps[0];
1391         ipn->in_ifps[1] = nat->nat_ifps[1];
1392         ipn->in_flags = (old->in_flags | IPN_PROXYRULE);
1393
1394         ipn->in_nsrcip6 = nat->nat_nsrc6;
1395         ipn->in_osrcip6 = nat->nat_osrc6;
1396         ipn->in_ndstip6 = nat->nat_ndst6;
1397         ipn->in_odstip6 = nat->nat_odst6;
1398         ipn->in_redir = old->in_redir;
1399
1400         if (ipn->in_v[0] == 4) {
1401                 ipn->in_snip = ntohl(nat->nat_nsrcaddr);
1402                 ipn->in_dnip = ntohl(nat->nat_ndstaddr);
1403 #ifdef USE_INET6
1404         } else {
1405                 ipn->in_snip6 = nat->nat_nsrc6;
1406                 ipn->in_dnip6 = nat->nat_ndst6;
1407 #endif
1408         }
1409
1410         IP6_SETONES(&ipn->in_osrcmsk6);
1411         IP6_SETONES(&ipn->in_nsrcmsk6);
1412         IP6_SETONES(&ipn->in_odstmsk6);
1413         IP6_SETONES(&ipn->in_ndstmsk6);
1414
1415         ipn->in_namelen = old->in_namelen;
1416         ipn->in_ifnames[0] = old->in_ifnames[0];
1417         ipn->in_ifnames[1] = old->in_ifnames[1];
1418         bcopy(old->in_names, ipn->in_names, ipn->in_namelen);
1419         MUTEX_INIT(&ipn->in_lock, "ipnat fwd rule lock");
1420
1421         return (ipn);
1422 }