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