1 /* 2 * Copyright (C) 1997-2003 by Darren Reed. 3 * 4 * See the IPFILTER.LICENCE file for details on licencing. 5 * 6 * Copyright 2006 Sun Microsystems, Inc. All rights reserved. 7 * Use is subject to license terms. 8 */ 9 10 #pragma ident "%Z%%M% %I% %E% SMI" 11 12 #if defined(KERNEL) || defined(_KERNEL) 13 # undef KERNEL 14 # undef _KERNEL 15 # define KERNEL 1 16 # define _KERNEL 1 17 #endif 18 #include <sys/errno.h> 19 #include <sys/types.h> 20 #include <sys/param.h> 21 #include <sys/time.h> 22 #include <sys/file.h> 23 #if !defined(AIX) 24 # include <sys/fcntl.h> 25 #endif 26 #if !defined(_KERNEL) && !defined(__KERNEL__) 27 # include <stdio.h> 28 # include <string.h> 29 # include <stdlib.h> 30 # include <ctype.h> 31 # define _KERNEL 32 # ifdef __OpenBSD__ 33 struct file; 34 # endif 35 # include <sys/uio.h> 36 # undef _KERNEL 37 #endif 38 #if !defined(linux) 39 # include <sys/protosw.h> 40 #endif 41 #include <sys/socket.h> 42 #if defined(_KERNEL) 43 # if !defined(__NetBSD__) && !defined(sun) && !defined(__osf__) && \ 44 !defined(__OpenBSD__) && !defined(__hpux) && !defined(__sgi) && \ 45 !defined(AIX) 46 # include <sys/ctype.h> 47 # endif 48 # include <sys/systm.h> 49 # if !defined(__SVR4) && !defined(__svr4__) 50 # include <sys/mbuf.h> 51 # endif 52 #endif 53 #if defined(_KERNEL) && (__FreeBSD_version >= 220000) 54 # include <sys/filio.h> 55 # include <sys/fcntl.h> 56 # if (__FreeBSD_version >= 300000) && !defined(IPFILTER_LKM) 57 # include "opt_ipfilter.h" 58 # endif 59 #else 60 # include <sys/ioctl.h> 61 #endif 62 #if defined(__SVR4) || defined(__svr4__) 63 # include <sys/byteorder.h> 64 # ifdef _KERNEL 65 # include <sys/dditypes.h> 66 # endif 67 # include <sys/stream.h> 68 # include <sys/kmem.h> 69 #endif 70 #if __FreeBSD__ > 2 71 # include <sys/queue.h> 72 #endif 73 #include <net/if.h> 74 #ifdef sun 75 # include <net/af.h> 76 #endif 77 #include <net/route.h> 78 #include <netinet/in.h> 79 #include <netinet/in_systm.h> 80 #include <netinet/ip.h> 81 #ifndef linux 82 # include <netinet/ip_var.h> 83 #endif 84 #include <netinet/tcp.h> 85 #include <netinet/udp.h> 86 #include <netinet/ip_icmp.h> 87 #include "netinet/ip_compat.h" 88 #include <netinet/tcpip.h> 89 #include "netinet/ip_fil.h" 90 #include "netinet/ip_nat.h" 91 #include "netinet/ip_state.h" 92 #include "netinet/ip_proxy.h" 93 #if (__FreeBSD_version >= 300000) 94 # include <sys/malloc.h> 95 #endif 96 97 #include "netinet/ip_ftp_pxy.c" 98 #include "netinet/ip_rcmd_pxy.c" 99 # include "netinet/ip_pptp_pxy.c" 100 #if defined(_KERNEL) 101 # include "netinet/ip_irc_pxy.c" 102 # include "netinet/ip_raudio_pxy.c" 103 # include "netinet/ip_h323_pxy.c" 104 # include "netinet/ip_netbios_pxy.c" 105 #endif 106 #include "netinet/ip_ipsec_pxy.c" 107 #include "netinet/ip_rpcb_pxy.c" 108 109 /* END OF INCLUDES */ 110 111 #if !defined(lint) 112 static const char rcsid[] = "@(#)$Id: ip_proxy.c,v 2.62.2.14 2005/06/18 02:41:33 darrenr Exp $"; 113 #endif 114 115 static int appr_fixseqack __P((fr_info_t *, ip_t *, ap_session_t *, int )); 116 117 #define AP_SESS_SIZE 53 118 119 #if defined(_KERNEL) 120 int ipf_proxy_debug = 0; 121 #else 122 int ipf_proxy_debug = 2; 123 #endif 124 ap_session_t *ap_sess_tab[AP_SESS_SIZE]; 125 ap_session_t *ap_sess_list = NULL; 126 aproxy_t *ap_proxylist = NULL; 127 aproxy_t ap_proxies[] = { 128 #ifdef IPF_FTP_PROXY 129 { NULL, "ftp", (char)IPPROTO_TCP, 0, 0, ippr_ftp_init, ippr_ftp_fini, 130 ippr_ftp_new, NULL, ippr_ftp_in, ippr_ftp_out, NULL }, 131 #endif 132 #ifdef IPF_IRC_PROXY 133 { NULL, "irc", (char)IPPROTO_TCP, 0, 0, ippr_irc_init, ippr_irc_fini, 134 ippr_irc_new, NULL, NULL, ippr_irc_out, NULL, NULL }, 135 #endif 136 #ifdef IPF_RCMD_PROXY 137 { NULL, "rcmd", (char)IPPROTO_TCP, 0, 0, ippr_rcmd_init, ippr_rcmd_fini, 138 ippr_rcmd_new, NULL, ippr_rcmd_in, ippr_rcmd_out, NULL, NULL }, 139 #endif 140 #ifdef IPF_RAUDIO_PROXY 141 { NULL, "raudio", (char)IPPROTO_TCP, 0, 0, ippr_raudio_init, ippr_raudio_fini, 142 ippr_raudio_new, NULL, ippr_raudio_in, ippr_raudio_out, NULL, NULL }, 143 #endif 144 #ifdef IPF_MSNRPC_PROXY 145 { NULL, "msnrpc", (char)IPPROTO_TCP, 0, 0, ippr_msnrpc_init, ippr_msnrpc_fini, 146 ippr_msnrpc_new, NULL, ippr_msnrpc_in, ippr_msnrpc_out, NULL, NULL }, 147 #endif 148 #ifdef IPF_NETBIOS_PROXY 149 { NULL, "netbios", (char)IPPROTO_UDP, 0, 0, ippr_netbios_init, ippr_netbios_fini, 150 NULL, NULL, NULL, ippr_netbios_out, NULL, NULL }, 151 #endif 152 #ifdef IPF_IPSEC_PROXY 153 { NULL, "ipsec", (char)IPPROTO_UDP, 0, 0, 154 ippr_ipsec_init, ippr_ipsec_fini, ippr_ipsec_new, ippr_ipsec_del, 155 ippr_ipsec_inout, ippr_ipsec_inout, ippr_ipsec_match, NULL }, 156 #endif 157 #ifdef IPF_PPTP_PROXY 158 { NULL, "pptp", (char)IPPROTO_TCP, 0, 0, 159 ippr_pptp_init, ippr_pptp_fini, ippr_pptp_new, ippr_pptp_del, 160 ippr_pptp_inout, ippr_pptp_inout, NULL, NULL }, 161 #endif 162 #ifdef IPF_H323_PROXY 163 { NULL, "h323", (char)IPPROTO_TCP, 0, 0, ippr_h323_init, ippr_h323_fini, 164 ippr_h323_new, ippr_h323_del, ippr_h323_in, NULL, NULL }, 165 { NULL, "h245", (char)IPPROTO_TCP, 0, 0, NULL, NULL, 166 ippr_h245_new, NULL, NULL, ippr_h245_out, NULL }, 167 #endif 168 #ifdef IPF_RPCB_PROXY 169 # if 0 170 { NULL, "rpcbt", (char)IPPROTO_TCP, 0, 0, 171 ippr_rpcb_init, ippr_rpcb_fini, ippr_rpcb_new, ippr_rpcb_del, 172 ippr_rpcb_in, ippr_rpcb_out, NULL, NULL }, 173 # endif 174 { NULL, "rpcbu", (char)IPPROTO_UDP, 0, 0, 175 ippr_rpcb_init, ippr_rpcb_fini, ippr_rpcb_new, ippr_rpcb_del, 176 ippr_rpcb_in, ippr_rpcb_out, NULL, NULL }, 177 #endif 178 { NULL, "", '\0', 0, 0, NULL, NULL, NULL, NULL } 179 }; 180 181 /* 182 * Dynamically add a new kernel proxy. Ensure that it is unique in the 183 * collection compiled in and dynamically added. 184 */ 185 int appr_add(ap) 186 aproxy_t *ap; 187 { 188 aproxy_t *a; 189 190 for (a = ap_proxies; a->apr_p; a++) 191 if ((a->apr_p == ap->apr_p) && 192 !strncmp(a->apr_label, ap->apr_label, 193 sizeof(ap->apr_label))) { 194 if (ipf_proxy_debug > 1) 195 printf("appr_add: %s/%d already present (B)\n", 196 a->apr_label, a->apr_p); 197 return -1; 198 } 199 200 for (a = ap_proxylist; a->apr_p; a = a->apr_next) 201 if ((a->apr_p == ap->apr_p) && 202 !strncmp(a->apr_label, ap->apr_label, 203 sizeof(ap->apr_label))) { 204 if (ipf_proxy_debug > 1) 205 printf("appr_add: %s/%d already present (D)\n", 206 a->apr_label, a->apr_p); 207 return -1; 208 } 209 ap->apr_next = ap_proxylist; 210 ap_proxylist = ap; 211 if (ap->apr_init != NULL) 212 return (*ap->apr_init)(); 213 return 0; 214 } 215 216 217 /* 218 * Check to see if the proxy this control request has come through for 219 * exists, and if it does and it has a control function then invoke that 220 * control function. 221 */ 222 int appr_ctl(ctl) 223 ap_ctl_t *ctl; 224 { 225 aproxy_t *a; 226 int error; 227 228 a = appr_lookup(ctl->apc_p, ctl->apc_label); 229 if (a == NULL) { 230 if (ipf_proxy_debug > 1) 231 printf("appr_ctl: can't find %s/%d\n", 232 ctl->apc_label, ctl->apc_p); 233 error = ESRCH; 234 } else if (a->apr_ctl == NULL) { 235 if (ipf_proxy_debug > 1) 236 printf("appr_ctl: no ctl function for %s/%d\n", 237 ctl->apc_label, ctl->apc_p); 238 error = ENXIO; 239 } else { 240 error = (*a->apr_ctl)(a, ctl); 241 if ((error != 0) && (ipf_proxy_debug > 1)) 242 printf("appr_ctl: %s/%d ctl error %d\n", 243 a->apr_label, a->apr_p, error); 244 } 245 return error; 246 } 247 248 249 /* 250 * Delete a proxy that has been added dynamically from those available. 251 * If it is in use, return 1 (do not destroy NOW), not in use 0 or -1 252 * if it cannot be matched. 253 */ 254 int appr_del(ap) 255 aproxy_t *ap; 256 { 257 aproxy_t *a, **app; 258 259 for (app = &ap_proxylist; ((a = *app) != NULL); app = &a->apr_next) 260 if (a == ap) { 261 a->apr_flags |= APR_DELETE; 262 *app = a->apr_next; 263 if (ap->apr_ref != 0) { 264 if (ipf_proxy_debug > 2) 265 printf("appr_del: orphaning %s/%d\n", 266 ap->apr_label, ap->apr_p); 267 return 1; 268 } 269 return 0; 270 } 271 if (ipf_proxy_debug > 1) 272 printf("appr_del: proxy %lx not found\n", (u_long)ap); 273 return -1; 274 } 275 276 277 /* 278 * Return 1 if the packet is a good match against a proxy, else 0. 279 */ 280 int appr_ok(fin, tcp, nat) 281 fr_info_t *fin; 282 tcphdr_t *tcp; 283 ipnat_t *nat; 284 { 285 aproxy_t *apr = nat->in_apr; 286 u_short dport = nat->in_dport; 287 288 if ((apr == NULL) || (apr->apr_flags & APR_DELETE) || 289 (fin->fin_p != apr->apr_p)) 290 return 0; 291 if ((tcp == NULL) && dport) 292 return 0; 293 return 1; 294 } 295 296 297 int appr_ioctl(data, cmd, mode) 298 caddr_t data; 299 ioctlcmd_t cmd; 300 int mode; 301 { 302 ap_ctl_t ctl; 303 caddr_t ptr; 304 int error; 305 306 mode = mode; /* LINT */ 307 308 switch (cmd) 309 { 310 case SIOCPROXY : 311 (void) BCOPYIN(data, &ctl, sizeof(ctl)); 312 ptr = NULL; 313 314 if (ctl.apc_dsize > 0) { 315 KMALLOCS(ptr, caddr_t, ctl.apc_dsize); 316 if (ptr == NULL) 317 error = ENOMEM; 318 else { 319 error = copyinptr(ctl.apc_data, ptr, 320 ctl.apc_dsize); 321 if (error == 0) 322 ctl.apc_data = ptr; 323 } 324 } else { 325 ctl.apc_data = NULL; 326 error = 0; 327 } 328 329 if (error == 0) 330 error = appr_ctl(&ctl); 331 332 if ((ctl.apc_dsize > 0) && (ptr != NULL) && 333 (ctl.apc_data == ptr)) { 334 KFREES(ptr, ctl.apc_dsize); 335 } 336 break; 337 338 default : 339 error = EINVAL; 340 } 341 return error; 342 } 343 344 345 /* 346 * If a proxy has a match function, call that to do extended packet 347 * matching. 348 */ 349 int appr_match(fin, nat) 350 fr_info_t *fin; 351 nat_t *nat; 352 { 353 aproxy_t *apr; 354 ipnat_t *ipn; 355 int result; 356 357 ipn = nat->nat_ptr; 358 if (ipf_proxy_debug > 8) 359 printf("appr_match(%lx,%lx) aps %lx ptr %lx\n", 360 (u_long)fin, (u_long)nat, (u_long)nat->nat_aps, 361 (u_long)ipn); 362 363 if ((fin->fin_flx & (FI_SHORT|FI_BAD)) != 0) { 364 if (ipf_proxy_debug > 0) 365 printf("appr_match: flx 0x%x (BAD|SHORT)\n", 366 fin->fin_flx); 367 return -1; 368 } 369 370 apr = ipn->in_apr; 371 if ((apr == NULL) || (apr->apr_flags & APR_DELETE)) { 372 if (ipf_proxy_debug > 0) 373 printf("appr_match:apr %lx apr_flags 0x%x\n", 374 (u_long)apr, apr ? apr->apr_flags : 0); 375 return -1; 376 } 377 378 if (apr->apr_match != NULL) { 379 result = (*apr->apr_match)(fin, nat->nat_aps, nat); 380 if (result != 0) { 381 if (ipf_proxy_debug > 4) 382 printf("appr_match: result %d\n", result); 383 return -1; 384 } 385 } 386 return 0; 387 } 388 389 390 /* 391 * Allocate a new application proxy structure and fill it in with the 392 * relevant details. call the init function once complete, prior to 393 * returning. 394 */ 395 int appr_new(fin, nat) 396 fr_info_t *fin; 397 nat_t *nat; 398 { 399 register ap_session_t *aps; 400 aproxy_t *apr; 401 402 if (ipf_proxy_debug > 8) 403 printf("appr_new(%lx,%lx) \n", (u_long)fin, (u_long)nat); 404 405 if ((nat->nat_ptr == NULL) || (nat->nat_aps != NULL)) { 406 if (ipf_proxy_debug > 0) 407 printf("appr_new: nat_ptr %lx nat_aps %lx\n", 408 (u_long)nat->nat_ptr, (u_long)nat->nat_aps); 409 return -1; 410 } 411 412 apr = nat->nat_ptr->in_apr; 413 414 if ((apr->apr_flags & APR_DELETE) || 415 (fin->fin_p != apr->apr_p)) { 416 if (ipf_proxy_debug > 2) 417 printf("appr_new: apr_flags 0x%x p %d/%d\n", 418 apr->apr_flags, fin->fin_p, apr->apr_p); 419 return -1; 420 } 421 422 KMALLOC(aps, ap_session_t *); 423 if (!aps) { 424 if (ipf_proxy_debug > 0) 425 printf("appr_new: malloc failed (%lu)\n", 426 (u_long)sizeof(ap_session_t)); 427 return -1; 428 } 429 430 bzero((char *)aps, sizeof(*aps)); 431 aps->aps_p = fin->fin_p; 432 aps->aps_data = NULL; 433 aps->aps_apr = apr; 434 aps->aps_psiz = 0; 435 if (apr->apr_new != NULL) 436 if ((*apr->apr_new)(fin, aps, nat) == -1) { 437 if ((aps->aps_data != NULL) && (aps->aps_psiz != 0)) { 438 KFREES(aps->aps_data, aps->aps_psiz); 439 } 440 KFREE(aps); 441 if (ipf_proxy_debug > 2) 442 printf("appr_new: new(%lx) failed\n", 443 (u_long)apr->apr_new); 444 return -1; 445 } 446 aps->aps_nat = nat; 447 aps->aps_next = ap_sess_list; 448 ap_sess_list = aps; 449 nat->nat_aps = aps; 450 451 return 0; 452 } 453 454 455 /* 456 * Check to see if a packet should be passed through an active proxy routine 457 * if one has been setup for it. We don't need to check the checksum here if 458 * IPFILTER_CKSUM is defined because if it is, a failed check causes FI_BAD 459 * to be set. 460 */ 461 int appr_check(fin, nat) 462 fr_info_t *fin; 463 nat_t *nat; 464 { 465 #if SOLARIS && defined(_KERNEL) && (SOLARIS2 >= 6) && defined(ICK_VALID) 466 mb_t *m; 467 int dosum = 1; 468 #endif 469 tcphdr_t *tcp = NULL; 470 udphdr_t *udp = NULL; 471 ap_session_t *aps; 472 aproxy_t *apr; 473 ip_t *ip; 474 short rv; 475 int err; 476 #if !defined(_KERNEL) || defined(MENTAT) || defined(__sgi) 477 u_32_t s1, s2, sd; 478 #endif 479 #if SOLARIS && defined(_KERNEL) && (SOLARIS2 >= 6) 480 net_data_t net_data_p; 481 if (fin->fin_v == 4) 482 net_data_p = ipf_ipv4; 483 else 484 net_data_p = ipf_ipv6; 485 #endif 486 487 if (fin->fin_flx & FI_BAD) { 488 if (ipf_proxy_debug > 0) 489 printf("appr_check: flx 0x%x (BAD)\n", fin->fin_flx); 490 return -1; 491 } 492 493 #ifndef IPFILTER_CKSUM 494 if ((fin->fin_out == 0) && (fr_checkl4sum(fin) == -1)) { 495 if (ipf_proxy_debug > 0) 496 printf("appr_check: l4 checksum failure %d\n", 497 fin->fin_p); 498 if (fin->fin_p == IPPROTO_TCP) 499 frstats[fin->fin_out].fr_tcpbad++; 500 return -1; 501 } 502 #endif 503 504 aps = nat->nat_aps; 505 if ((aps != NULL) && (aps->aps_p == fin->fin_p)) { 506 /* 507 * If there is data in this packet to be proxied then try and 508 * get it all into the one buffer, else drop it. 509 */ 510 #if defined(MENTAT) || defined(HAVE_M_PULLDOWN) 511 if ((fin->fin_dlen > 0) && !(fin->fin_flx & FI_COALESCE)) 512 if (fr_coalesce(fin) == -1) { 513 if (ipf_proxy_debug > 0) 514 printf("appr_check: fr_coalesce failed %x\n", fin->fin_flx); 515 return -1; 516 } 517 #endif 518 ip = fin->fin_ip; 519 520 switch (fin->fin_p) 521 { 522 case IPPROTO_TCP : 523 tcp = (tcphdr_t *)fin->fin_dp; 524 525 #if SOLARIS && defined(_KERNEL) && (SOLARIS2 >= 6) && defined(ICK_VALID) 526 m = fin->fin_qfm; 527 if (dohwcksum && (m->b_ick_flag == ICK_VALID)) 528 dosum = 0; 529 #endif 530 /* 531 * Don't bother the proxy with these...or in fact, 532 * should we free up proxy stuff when seen? 533 */ 534 if ((fin->fin_tcpf & TH_RST) != 0) 535 break; 536 /*FALLTHROUGH*/ 537 case IPPROTO_UDP : 538 udp = (udphdr_t *)fin->fin_dp; 539 break; 540 default : 541 break; 542 } 543 544 apr = aps->aps_apr; 545 err = 0; 546 if (fin->fin_out != 0) { 547 if (apr->apr_outpkt != NULL) 548 err = (*apr->apr_outpkt)(fin, aps, nat); 549 } else { 550 if (apr->apr_inpkt != NULL) 551 err = (*apr->apr_inpkt)(fin, aps, nat); 552 } 553 554 rv = APR_EXIT(err); 555 if (((ipf_proxy_debug > 0) && (rv != 0)) || 556 (ipf_proxy_debug > 8)) 557 printf("appr_check: out %d err %x rv %d\n", 558 fin->fin_out, err, rv); 559 if (rv == 1) 560 return -1; 561 562 if (rv == 2) { 563 appr_free(apr); 564 nat->nat_aps = NULL; 565 return -1; 566 } 567 568 /* 569 * If err != 0 then the data size of the packet has changed 570 * so we need to recalculate the header checksums for the 571 * packet. 572 * inbound packets always need to be adjusted. 573 */ 574 #if !defined(_KERNEL) || defined(MENTAT) || defined(__sgi) 575 if (err != 0 && (!fin->fin_out || 576 !NET_IS_HCK_L3_FULL(net_data_p, fin->fin_m))) { 577 short adjlen = err & 0xffff; 578 579 s1 = LONG_SUM(ip->ip_len - adjlen); 580 s2 = LONG_SUM(ip->ip_len); 581 CALC_SUMD(s1, s2, sd); 582 fix_outcksum(&ip->ip_sum, sd); 583 } 584 #endif 585 586 /* 587 * For TCP packets, we may need to adjust the sequence and 588 * acknowledgement numbers to reflect changes in size of the 589 * data stream. 590 * 591 * For both TCP and UDP, recalculate the layer 4 checksum, 592 * regardless, as we can't tell (here) if data has been 593 * changed or not. 594 */ 595 if (tcp != NULL) { 596 err = appr_fixseqack(fin, ip, aps, APR_INC(err)); 597 #if SOLARIS && defined(_KERNEL) && (SOLARIS2 >= 6) 598 if (!fin->fin_out || 599 !NET_IS_HCK_L4_FULL(net_data_p, fin->fin_m) && 600 !NET_IS_HCK_L4_PART(net_data_p, fin->fin_m)) 601 tcp->th_sum = fr_cksum(fin->fin_qfm, ip, 602 IPPROTO_TCP, tcp); 603 #else 604 tcp->th_sum = fr_cksum(fin->fin_m, ip, 605 IPPROTO_TCP, tcp); 606 #endif 607 } else if ((udp != NULL) && (udp->uh_sum != 0)) { 608 #if SOLARIS && defined(_KERNEL) && (SOLARIS2 >= 6) 609 if (!fin->fin_out || 610 !NET_IS_HCK_L4_FULL(net_data_p, fin->fin_m) && 611 !NET_IS_HCK_L4_PART(net_data_p, fin->fin_m)) 612 udp->uh_sum = fr_cksum(fin->fin_qfm, ip, 613 IPPROTO_UDP, udp); 614 #else 615 udp->uh_sum = fr_cksum(fin->fin_m, ip, 616 IPPROTO_UDP, udp); 617 #endif 618 } 619 aps->aps_bytes += fin->fin_plen; 620 aps->aps_pkts++; 621 return 1; 622 } 623 return 0; 624 } 625 626 627 /* 628 * Search for an proxy by the protocol it is being used with and its name. 629 */ 630 aproxy_t *appr_lookup(pr, name) 631 u_int pr; 632 char *name; 633 { 634 aproxy_t *ap; 635 636 if (ipf_proxy_debug > 8) 637 printf("appr_lookup(%d,%s)\n", pr, name); 638 639 for (ap = ap_proxies; ap->apr_p; ap++) 640 if ((ap->apr_p == pr) && 641 !strncmp(name, ap->apr_label, sizeof(ap->apr_label))) { 642 ap->apr_ref++; 643 return ap; 644 } 645 646 for (ap = ap_proxylist; ap; ap = ap->apr_next) 647 if ((ap->apr_p == pr) && 648 !strncmp(name, ap->apr_label, sizeof(ap->apr_label))) { 649 ap->apr_ref++; 650 return ap; 651 } 652 if (ipf_proxy_debug > 2) 653 printf("appr_lookup: failed for %d/%s\n", pr, name); 654 return NULL; 655 } 656 657 658 void appr_free(ap) 659 aproxy_t *ap; 660 { 661 ap->apr_ref--; 662 } 663 664 665 void aps_free(aps) 666 ap_session_t *aps; 667 { 668 ap_session_t *a, **ap; 669 aproxy_t *apr; 670 671 if (!aps) 672 return; 673 674 for (ap = &ap_sess_list; ((a = *ap) != NULL); ap = &a->aps_next) 675 if (a == aps) { 676 *ap = a->aps_next; 677 break; 678 } 679 680 apr = aps->aps_apr; 681 if ((apr != NULL) && (apr->apr_del != NULL)) 682 (*apr->apr_del)(aps); 683 684 if ((aps->aps_data != NULL) && (aps->aps_psiz != 0)) 685 KFREES(aps->aps_data, aps->aps_psiz); 686 KFREE(aps); 687 } 688 689 690 /* 691 * returns 2 if ack or seq number in TCP header is changed, returns 0 otherwise 692 */ 693 static int appr_fixseqack(fin, ip, aps, inc) 694 fr_info_t *fin; 695 ip_t *ip; 696 ap_session_t *aps; 697 int inc; 698 { 699 int sel, ch = 0, out, nlen; 700 u_32_t seq1, seq2; 701 tcphdr_t *tcp; 702 short inc2; 703 704 tcp = (tcphdr_t *)fin->fin_dp; 705 out = fin->fin_out; 706 /* 707 * ip_len has already been adjusted by 'inc'. 708 */ 709 nlen = ip->ip_len; 710 nlen -= (IP_HL(ip) << 2) + (TCP_OFF(tcp) << 2); 711 712 inc2 = inc; 713 inc = (int)inc2; 714 715 if (out != 0) { 716 seq1 = (u_32_t)ntohl(tcp->th_seq); 717 sel = aps->aps_sel[out]; 718 719 /* switch to other set ? */ 720 if ((aps->aps_seqmin[!sel] > aps->aps_seqmin[sel]) && 721 (seq1 > aps->aps_seqmin[!sel])) { 722 if (ipf_proxy_debug > 7) 723 printf("proxy out switch set seq %d -> %d %x > %x\n", 724 sel, !sel, seq1, 725 aps->aps_seqmin[!sel]); 726 sel = aps->aps_sel[out] = !sel; 727 } 728 729 if (aps->aps_seqoff[sel]) { 730 seq2 = aps->aps_seqmin[sel] - aps->aps_seqoff[sel]; 731 if (seq1 > seq2) { 732 seq2 = aps->aps_seqoff[sel]; 733 seq1 += seq2; 734 tcp->th_seq = htonl(seq1); 735 ch = 1; 736 } 737 } 738 739 if (inc && (seq1 > aps->aps_seqmin[!sel])) { 740 aps->aps_seqmin[sel] = seq1 + nlen - 1; 741 aps->aps_seqoff[sel] = aps->aps_seqoff[sel] + inc; 742 if (ipf_proxy_debug > 7) 743 printf("proxy seq set %d at %x to %d + %d\n", 744 sel, aps->aps_seqmin[sel], 745 aps->aps_seqoff[sel], inc); 746 } 747 748 /***/ 749 750 seq1 = ntohl(tcp->th_ack); 751 sel = aps->aps_sel[1 - out]; 752 753 /* switch to other set ? */ 754 if ((aps->aps_ackmin[!sel] > aps->aps_ackmin[sel]) && 755 (seq1 > aps->aps_ackmin[!sel])) { 756 if (ipf_proxy_debug > 7) 757 printf("proxy out switch set ack %d -> %d %x > %x\n", 758 sel, !sel, seq1, 759 aps->aps_ackmin[!sel]); 760 sel = aps->aps_sel[1 - out] = !sel; 761 } 762 763 if (aps->aps_ackoff[sel] && (seq1 > aps->aps_ackmin[sel])) { 764 seq2 = aps->aps_ackoff[sel]; 765 tcp->th_ack = htonl(seq1 - seq2); 766 ch = 1; 767 } 768 } else { 769 seq1 = ntohl(tcp->th_seq); 770 sel = aps->aps_sel[out]; 771 772 /* switch to other set ? */ 773 if ((aps->aps_ackmin[!sel] > aps->aps_ackmin[sel]) && 774 (seq1 > aps->aps_ackmin[!sel])) { 775 if (ipf_proxy_debug > 7) 776 printf("proxy in switch set ack %d -> %d %x > %x\n", 777 sel, !sel, seq1, aps->aps_ackmin[!sel]); 778 sel = aps->aps_sel[out] = !sel; 779 } 780 781 if (aps->aps_ackoff[sel]) { 782 seq2 = aps->aps_ackmin[sel] - aps->aps_ackoff[sel]; 783 if (seq1 > seq2) { 784 seq2 = aps->aps_ackoff[sel]; 785 seq1 += seq2; 786 tcp->th_seq = htonl(seq1); 787 ch = 1; 788 } 789 } 790 791 if (inc && (seq1 > aps->aps_ackmin[!sel])) { 792 aps->aps_ackmin[!sel] = seq1 + nlen - 1; 793 aps->aps_ackoff[!sel] = aps->aps_ackoff[sel] + inc; 794 795 if (ipf_proxy_debug > 7) 796 printf("proxy ack set %d at %x to %d + %d\n", 797 !sel, aps->aps_seqmin[!sel], 798 aps->aps_seqoff[sel], inc); 799 } 800 801 /***/ 802 803 seq1 = ntohl(tcp->th_ack); 804 sel = aps->aps_sel[1 - out]; 805 806 /* switch to other set ? */ 807 if ((aps->aps_seqmin[!sel] > aps->aps_seqmin[sel]) && 808 (seq1 > aps->aps_seqmin[!sel])) { 809 if (ipf_proxy_debug > 7) 810 printf("proxy in switch set seq %d -> %d %x > %x\n", 811 sel, !sel, seq1, aps->aps_seqmin[!sel]); 812 sel = aps->aps_sel[1 - out] = !sel; 813 } 814 815 if (aps->aps_seqoff[sel] != 0) { 816 if (ipf_proxy_debug > 7) 817 printf("sel %d seqoff %d seq1 %x seqmin %x\n", 818 sel, aps->aps_seqoff[sel], seq1, 819 aps->aps_seqmin[sel]); 820 if (seq1 > aps->aps_seqmin[sel]) { 821 seq2 = aps->aps_seqoff[sel]; 822 tcp->th_ack = htonl(seq1 - seq2); 823 ch = 1; 824 } 825 } 826 } 827 828 if (ipf_proxy_debug > 8) 829 printf("appr_fixseqack: seq %x ack %x\n", 830 ntohl(tcp->th_seq), ntohl(tcp->th_ack)); 831 return ch ? 2 : 0; 832 } 833 834 835 /* 836 * Initialise hook for kernel application proxies. 837 * Call the initialise routine for all the compiled in kernel proxies. 838 */ 839 int appr_init() 840 { 841 aproxy_t *ap; 842 int err = 0; 843 844 for (ap = ap_proxies; ap->apr_p; ap++) { 845 if (ap->apr_init != NULL) { 846 err = (*ap->apr_init)(); 847 if (err != 0) 848 break; 849 } 850 } 851 return err; 852 } 853 854 855 /* 856 * Unload hook for kernel application proxies. 857 * Call the finialise routine for all the compiled in kernel proxies. 858 */ 859 void appr_unload() 860 { 861 aproxy_t *ap; 862 863 for (ap = ap_proxies; ap->apr_p; ap++) 864 if (ap->apr_fini != NULL) 865 (*ap->apr_fini)(); 866 for (ap = ap_proxylist; ap; ap = ap->apr_next) 867 if (ap->apr_fini != NULL) 868 (*ap->apr_fini)(); 869 } 870