1 /* 2 * Copyright (C) 1997-2003 by Darren Reed. 3 * 4 * See the IPFILTER.LICENCE file for details on licencing. 5 * 6 * Copyright 2008 Sun Microsystems, Inc. All rights reserved. 7 * Use is subject to license terms. 8 */ 9 10 #if defined(KERNEL) || defined(_KERNEL) 11 # undef KERNEL 12 # undef _KERNEL 13 # define KERNEL 1 14 # define _KERNEL 1 15 #endif 16 #include <sys/errno.h> 17 #include <sys/types.h> 18 #include <sys/param.h> 19 #include <sys/time.h> 20 #include <sys/file.h> 21 #if !defined(AIX) 22 # include <sys/fcntl.h> 23 #endif 24 #if !defined(_KERNEL) && !defined(__KERNEL__) 25 # include <stdio.h> 26 # include <string.h> 27 # include <stdlib.h> 28 # include <ctype.h> 29 # define _KERNEL 30 # ifdef __OpenBSD__ 31 struct file; 32 # endif 33 # include <sys/uio.h> 34 # undef _KERNEL 35 #endif 36 #if !defined(linux) 37 # include <sys/protosw.h> 38 #endif 39 #include <sys/socket.h> 40 #if defined(_KERNEL) 41 # if !defined(__NetBSD__) && !defined(sun) && !defined(__osf__) && \ 42 !defined(__OpenBSD__) && !defined(__hpux) && !defined(__sgi) && \ 43 !defined(AIX) 44 # include <sys/ctype.h> 45 # endif 46 # include <sys/systm.h> 47 # if !defined(__SVR4) && !defined(__svr4__) 48 # include <sys/mbuf.h> 49 # endif 50 #endif 51 #if defined(_KERNEL) && (__FreeBSD_version >= 220000) 52 # include <sys/filio.h> 53 # include <sys/fcntl.h> 54 # if (__FreeBSD_version >= 300000) && !defined(IPFILTER_LKM) 55 # include "opt_ipfilter.h" 56 # endif 57 #else 58 # include <sys/ioctl.h> 59 #endif 60 #if defined(__SVR4) || defined(__svr4__) 61 # include <sys/byteorder.h> 62 # ifdef _KERNEL 63 # include <sys/dditypes.h> 64 # include <sys/strsubr.h> 65 # endif 66 # include <sys/stream.h> 67 # include <sys/kmem.h> 68 # include <sys/pattr.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/ipf_stack.h" 90 #include "netinet/ip_fil.h" 91 #include "netinet/ip_nat.h" 92 #include "netinet/ip_state.h" 93 #include "netinet/ip_proxy.h" 94 #if (__FreeBSD_version >= 300000) 95 # include <sys/malloc.h> 96 #endif 97 98 #include "netinet/ip_ftp_pxy.c" 99 #include "netinet/ip_rcmd_pxy.c" 100 # include "netinet/ip_pptp_pxy.c" 101 #if defined(_KERNEL) 102 # include "netinet/ip_irc_pxy.c" 103 # include "netinet/ip_raudio_pxy.c" 104 # include "netinet/ip_h323_pxy.c" 105 # include "netinet/ip_netbios_pxy.c" 106 #endif 107 #include "netinet/ip_ipsec_pxy.c" 108 #include "netinet/ip_rpcb_pxy.c" 109 110 /* END OF INCLUDES */ 111 112 #if !defined(lint) 113 static const char rcsid[] = "@(#)$Id: ip_proxy.c,v 2.62.2.14 2005/06/18 02:41:33 darrenr Exp $"; 114 #endif 115 116 static int appr_fixseqack __P((fr_info_t *, ip_t *, ap_session_t *, int )); 117 118 #define AP_SESS_SIZE 53 119 120 #if defined(_KERNEL) 121 int ipf_proxy_debug = 0; 122 #else 123 int ipf_proxy_debug = 2; 124 #endif 125 126 static aproxy_t lcl_ap_proxies[] = { 127 #ifdef IPF_FTP_PROXY 128 { NULL, "ftp", (char)IPPROTO_TCP, 0, 0, NULL, ippr_ftp_init, ippr_ftp_fini, 129 ippr_ftp_new, NULL, ippr_ftp_in, ippr_ftp_out, NULL }, 130 #endif 131 #ifdef IPF_IRC_PROXY 132 { NULL, "irc", (char)IPPROTO_TCP, 0, 0, NULL, ippr_irc_init, ippr_irc_fini, 133 ippr_irc_new, NULL, NULL, ippr_irc_out, NULL, NULL }, 134 #endif 135 #ifdef IPF_RCMD_PROXY 136 { NULL, "rcmd", (char)IPPROTO_TCP, 0, 0, NULL, ippr_rcmd_init, ippr_rcmd_fini, 137 ippr_rcmd_new, NULL, ippr_rcmd_in, ippr_rcmd_out, NULL, NULL }, 138 #endif 139 #ifdef IPF_RAUDIO_PROXY 140 { NULL, "raudio", (char)IPPROTO_TCP, 0, 0, NULL, ippr_raudio_init, ippr_raudio_fini, 141 ippr_raudio_new, NULL, ippr_raudio_in, ippr_raudio_out, NULL, NULL }, 142 #endif 143 #ifdef IPF_MSNRPC_PROXY 144 { NULL, "msnrpc", (char)IPPROTO_TCP, 0, 0, NULL, ippr_msnrpc_init, ippr_msnrpc_fini, 145 ippr_msnrpc_new, NULL, ippr_msnrpc_in, ippr_msnrpc_out, NULL, NULL }, 146 #endif 147 #ifdef IPF_NETBIOS_PROXY 148 { NULL, "netbios", (char)IPPROTO_UDP, 0, 0, NULL, ippr_netbios_init, ippr_netbios_fini, 149 NULL, NULL, NULL, ippr_netbios_out, NULL, NULL }, 150 #endif 151 #ifdef IPF_IPSEC_PROXY 152 { NULL, "ipsec", (char)IPPROTO_UDP, 0, 0, NULL, 153 ippr_ipsec_init, ippr_ipsec_fini, ippr_ipsec_new, ippr_ipsec_del, 154 ippr_ipsec_inout, ippr_ipsec_inout, ippr_ipsec_match, NULL }, 155 #endif 156 #ifdef IPF_PPTP_PROXY 157 { NULL, "pptp", (char)IPPROTO_TCP, 0, 0, NULL, 158 ippr_pptp_init, ippr_pptp_fini, ippr_pptp_new, ippr_pptp_del, 159 ippr_pptp_inout, ippr_pptp_inout, NULL, NULL }, 160 #endif 161 #ifdef IPF_H323_PROXY 162 { NULL, "h323", (char)IPPROTO_TCP, 0, 0, NULL, ippr_h323_init, ippr_h323_fini, 163 ippr_h323_new, ippr_h323_del, ippr_h323_in, NULL, NULL }, 164 { NULL, "h245", (char)IPPROTO_TCP, 0, 0, NULL, NULL, NULL, 165 ippr_h245_new, NULL, NULL, ippr_h245_out, NULL }, 166 #endif 167 #ifdef IPF_RPCB_PROXY 168 # if 0 169 { NULL, "rpcbt", (char)IPPROTO_TCP, 0, 0, NULL, 170 ippr_rpcb_init, ippr_rpcb_fini, ippr_rpcb_new, ippr_rpcb_del, 171 ippr_rpcb_in, ippr_rpcb_out, NULL, NULL }, 172 # endif 173 { NULL, "rpcbu", (char)IPPROTO_UDP, 0, 0, NULL, 174 ippr_rpcb_init, ippr_rpcb_fini, ippr_rpcb_new, ippr_rpcb_del, 175 ippr_rpcb_in, ippr_rpcb_out, NULL, NULL }, 176 #endif 177 { NULL, "", '\0', 0, 0, NULL, NULL, NULL, NULL, NULL } 178 }; 179 180 /* 181 * Dynamically add a new kernel proxy. Ensure that it is unique in the 182 * collection compiled in and dynamically added. 183 */ 184 int appr_add(ap, ifs) 185 aproxy_t *ap; 186 ipf_stack_t *ifs; 187 { 188 aproxy_t *a; 189 190 for (a = ifs->ifs_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 = ifs->ifs_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 = ifs->ifs_ap_proxylist; 210 ifs->ifs_ap_proxylist = ap; 211 if (ap->apr_init != NULL) 212 return (*ap->apr_init)(&ap->apr_private, ifs); 213 214 return 0; 215 } 216 217 218 /* 219 * Check to see if the proxy this control request has come through for 220 * exists, and if it does and it has a control function then invoke that 221 * control function. 222 */ 223 int appr_ctl(ctl, ifs) 224 ap_ctl_t *ctl; 225 ipf_stack_t *ifs; 226 { 227 aproxy_t *a; 228 int error; 229 230 a = appr_lookup(ctl->apc_p, ctl->apc_label, ifs); 231 if (a == NULL) { 232 if (ipf_proxy_debug > 1) 233 printf("appr_ctl: can't find %s/%d\n", 234 ctl->apc_label, ctl->apc_p); 235 error = ESRCH; 236 } else if (a->apr_ctl == NULL) { 237 if (ipf_proxy_debug > 1) 238 printf("appr_ctl: no ctl function for %s/%d\n", 239 ctl->apc_label, ctl->apc_p); 240 error = ENXIO; 241 } else { 242 error = (*a->apr_ctl)(a, ctl, a->apr_private); 243 if ((error != 0) && (ipf_proxy_debug > 1)) 244 printf("appr_ctl: %s/%d ctl error %d\n", 245 a->apr_label, a->apr_p, error); 246 } 247 return error; 248 } 249 250 251 /* 252 * Delete a proxy that has been added dynamically from those available. 253 * If it is in use, return 1 (do not destroy NOW), not in use 0 or -1 254 * if it cannot be matched. 255 */ 256 int appr_del(ap, ifs) 257 aproxy_t *ap; 258 ipf_stack_t *ifs; 259 { 260 aproxy_t *a, **app; 261 262 for (app = &ifs->ifs_ap_proxylist; ((a = *app) != NULL); 263 app = &a->apr_next) 264 if (a == ap) { 265 a->apr_flags |= APR_DELETE; 266 *app = a->apr_next; 267 if (ap->apr_ref != 0) { 268 if (ipf_proxy_debug > 2) 269 printf("appr_del: orphaning %s/%d\n", 270 ap->apr_label, ap->apr_p); 271 return 1; 272 } 273 return 0; 274 } 275 if (ipf_proxy_debug > 1) 276 printf("appr_del: proxy %lx not found\n", (u_long)ap); 277 return -1; 278 } 279 280 281 /* 282 * Return 1 if the packet is a good match against a proxy, else 0. 283 */ 284 int appr_ok(fin, tcp, nat) 285 fr_info_t *fin; 286 tcphdr_t *tcp; 287 ipnat_t *nat; 288 { 289 aproxy_t *apr = nat->in_apr; 290 u_short dport = nat->in_dport; 291 292 if ((apr == NULL) || (apr->apr_flags & APR_DELETE) || 293 (fin->fin_p != apr->apr_p)) 294 return 0; 295 if ((tcp == NULL) && dport) 296 return 0; 297 return 1; 298 } 299 300 301 int appr_ioctl(data, cmd, mode, ifs) 302 caddr_t data; 303 ioctlcmd_t cmd; 304 int mode; 305 ipf_stack_t *ifs; 306 { 307 ap_ctl_t ctl; 308 caddr_t ptr; 309 int error; 310 311 mode = mode; /* LINT */ 312 313 switch (cmd) 314 { 315 case SIOCPROXY : 316 error = BCOPYIN(data, &ctl, sizeof(ctl)); 317 if (error != 0) 318 return EFAULT; 319 320 ptr = NULL; 321 322 if (ctl.apc_dsize > 0) { 323 KMALLOCS(ptr, caddr_t, ctl.apc_dsize); 324 if (ptr == NULL) 325 error = ENOMEM; 326 else { 327 error = copyinptr(ctl.apc_data, ptr, 328 ctl.apc_dsize); 329 if (error == 0) 330 ctl.apc_data = ptr; 331 } 332 } else { 333 ctl.apc_data = NULL; 334 error = 0; 335 } 336 337 if (error == 0) 338 error = appr_ctl(&ctl, ifs); 339 340 if ((ctl.apc_dsize > 0) && (ptr != NULL) && 341 (ctl.apc_data == ptr)) { 342 KFREES(ptr, ctl.apc_dsize); 343 } 344 break; 345 346 default : 347 error = EINVAL; 348 } 349 return error; 350 } 351 352 353 /* 354 * If a proxy has a match function, call that to do extended packet 355 * matching. 356 */ 357 int appr_match(fin, nat) 358 fr_info_t *fin; 359 nat_t *nat; 360 { 361 aproxy_t *apr; 362 ipnat_t *ipn; 363 int result; 364 365 ipn = nat->nat_ptr; 366 if (ipf_proxy_debug > 8) 367 printf("appr_match(%lx,%lx) aps %lx ptr %lx\n", 368 (u_long)fin, (u_long)nat, (u_long)nat->nat_aps, 369 (u_long)ipn); 370 371 if ((fin->fin_flx & (FI_SHORT|FI_BAD)) != 0) { 372 if (ipf_proxy_debug > 0) 373 printf("appr_match: flx 0x%x (BAD|SHORT)\n", 374 fin->fin_flx); 375 return -1; 376 } 377 378 apr = ipn->in_apr; 379 if ((apr == NULL) || (apr->apr_flags & APR_DELETE)) { 380 if (ipf_proxy_debug > 0) 381 printf("appr_match:apr %lx apr_flags 0x%x\n", 382 (u_long)apr, apr ? apr->apr_flags : 0); 383 return -1; 384 } 385 386 if (apr->apr_match != NULL) { 387 result = (*apr->apr_match)(fin, nat->nat_aps, nat, apr->apr_private); 388 if (result != 0) { 389 if (ipf_proxy_debug > 4) 390 printf("appr_match: result %d\n", result); 391 return -1; 392 } 393 } 394 return 0; 395 } 396 397 398 /* 399 * Allocate a new application proxy structure and fill it in with the 400 * relevant details. call the init function once complete, prior to 401 * returning. 402 */ 403 int appr_new(fin, nat) 404 fr_info_t *fin; 405 nat_t *nat; 406 { 407 register ap_session_t *aps; 408 aproxy_t *apr; 409 ipf_stack_t *ifs = fin->fin_ifs; 410 411 if (ipf_proxy_debug > 8) 412 printf("appr_new(%lx,%lx) \n", (u_long)fin, (u_long)nat); 413 414 if ((nat->nat_ptr == NULL) || (nat->nat_aps != NULL)) { 415 if (ipf_proxy_debug > 0) 416 printf("appr_new: nat_ptr %lx nat_aps %lx\n", 417 (u_long)nat->nat_ptr, (u_long)nat->nat_aps); 418 return -1; 419 } 420 421 apr = nat->nat_ptr->in_apr; 422 423 if ((apr->apr_flags & APR_DELETE) || 424 (fin->fin_p != apr->apr_p)) { 425 if (ipf_proxy_debug > 2) 426 printf("appr_new: apr_flags 0x%x p %d/%d\n", 427 apr->apr_flags, fin->fin_p, apr->apr_p); 428 return -1; 429 } 430 431 KMALLOC(aps, ap_session_t *); 432 if (!aps) { 433 if (ipf_proxy_debug > 0) 434 printf("appr_new: malloc failed (%lu)\n", 435 (u_long)sizeof(ap_session_t)); 436 return -1; 437 } 438 439 bzero((char *)aps, sizeof(*aps)); 440 aps->aps_p = fin->fin_p; 441 aps->aps_data = NULL; 442 aps->aps_apr = apr; 443 aps->aps_psiz = 0; 444 if (apr->apr_new != NULL) 445 if ((*apr->apr_new)(fin, aps, nat, apr->apr_private) == -1) { 446 if ((aps->aps_data != NULL) && (aps->aps_psiz != 0)) { 447 KFREES(aps->aps_data, aps->aps_psiz); 448 } 449 KFREE(aps); 450 if (ipf_proxy_debug > 2) 451 printf("appr_new: new(%lx) failed\n", 452 (u_long)apr->apr_new); 453 return -1; 454 } 455 aps->aps_nat = nat; 456 aps->aps_next = ifs->ifs_ap_sess_list; 457 ifs->ifs_ap_sess_list = aps; 458 nat->nat_aps = aps; 459 460 return 0; 461 } 462 463 464 /* 465 * Check to see if a packet should be passed through an active proxy routine 466 * if one has been setup for it. We don't need to check the checksum here if 467 * IPFILTER_CKSUM is defined because if it is, a failed check causes FI_BAD 468 * to be set. 469 */ 470 int appr_check(fin, nat) 471 fr_info_t *fin; 472 nat_t *nat; 473 { 474 #if SOLARIS && defined(_KERNEL) && (SOLARIS2 >= 6) && defined(ICK_VALID) 475 mb_t *m; 476 int dosum = 1; 477 #endif 478 tcphdr_t *tcp = NULL; 479 udphdr_t *udp = NULL; 480 void *tcpudp = NULL; 481 u_short *csump; 482 ap_session_t *aps; 483 aproxy_t *apr; 484 ip_t *ip; 485 short rv; 486 int err; 487 #if !defined(_KERNEL) || defined(MENTAT) || defined(__sgi) 488 u_32_t s1, s2, sd; 489 #endif 490 ipf_stack_t *ifs = fin->fin_ifs; 491 492 #if SOLARIS && defined(_KERNEL) && (SOLARIS2 >= 6) 493 net_handle_t net_data_p; 494 if (fin->fin_v == 4) 495 net_data_p = ifs->ifs_ipf_ipv4; 496 else 497 net_data_p = ifs->ifs_ipf_ipv6; 498 #endif 499 500 if (fin->fin_flx & FI_BAD) { 501 if (ipf_proxy_debug > 0) 502 printf("appr_check: flx 0x%x (BAD)\n", fin->fin_flx); 503 return -1; 504 } 505 506 #ifndef IPFILTER_CKSUM 507 if ((fin->fin_out == 0) && (fr_checkl4sum(fin) == -1)) { 508 if (ipf_proxy_debug > 0) 509 printf("appr_check: l4 checksum failure %d\n", 510 fin->fin_p); 511 if (fin->fin_p == IPPROTO_TCP) 512 ifs->ifs_frstats[fin->fin_out].fr_tcpbad++; 513 return -1; 514 } 515 #endif 516 517 aps = nat->nat_aps; 518 if ((aps != NULL) && (aps->aps_p == fin->fin_p)) { 519 /* 520 * If there is data in this packet to be proxied then try and 521 * get it all into the one buffer, else drop it. 522 */ 523 #if defined(MENTAT) || defined(HAVE_M_PULLDOWN) 524 if ((fin->fin_dlen > 0) && !(fin->fin_flx & FI_COALESCE)) 525 if (fr_coalesce(fin) == -1) { 526 if (ipf_proxy_debug > 0) 527 printf("appr_check: fr_coalesce failed %x\n", fin->fin_flx); 528 return -1; 529 } 530 #endif 531 ip = fin->fin_ip; 532 533 switch (fin->fin_p) 534 { 535 case IPPROTO_TCP : 536 tcp = (tcphdr_t *)fin->fin_dp; 537 538 #if SOLARIS && defined(_KERNEL) && (SOLARIS2 >= 6) && defined(ICK_VALID) 539 m = fin->fin_qfm; 540 if (dohwcksum && (m->b_ick_flag == ICK_VALID)) 541 dosum = 0; 542 #endif 543 /* 544 * Don't bother the proxy with these...or in fact, 545 * should we free up proxy stuff when seen? 546 */ 547 if ((fin->fin_tcpf & TH_RST) != 0) 548 break; 549 /*FALLTHROUGH*/ 550 case IPPROTO_UDP : 551 udp = (udphdr_t *)fin->fin_dp; 552 break; 553 default : 554 break; 555 } 556 557 apr = aps->aps_apr; 558 err = 0; 559 if (fin->fin_out != 0) { 560 if (apr->apr_outpkt != NULL) 561 err = (*apr->apr_outpkt)(fin, aps, nat, apr->apr_private); 562 } else { 563 if (apr->apr_inpkt != NULL) 564 err = (*apr->apr_inpkt)(fin, aps, nat, apr->apr_private); 565 } 566 567 rv = APR_EXIT(err); 568 if (((ipf_proxy_debug > 0) && (rv != 0)) || 569 (ipf_proxy_debug > 8)) 570 printf("appr_check: out %d err %x rv %d\n", 571 fin->fin_out, err, rv); 572 if (rv == 1) 573 return -1; 574 575 if (rv == 2) { 576 appr_free(apr); 577 nat->nat_aps = NULL; 578 return -1; 579 } 580 581 /* 582 * If err != 0 then the data size of the packet has changed 583 * so we need to recalculate the header checksums for the 584 * packet. 585 * inbound packets always need to be adjusted. 586 */ 587 #if !defined(_KERNEL) || defined(MENTAT) || defined(__sgi) 588 if (err != 0) { 589 short adjlen = err & 0xffff; 590 591 s1 = LONG_SUM(ip->ip_len - adjlen); 592 s2 = LONG_SUM(ip->ip_len); 593 CALC_SUMD(s1, s2, sd); 594 sd = (sd & 0xffff) + (sd >> 16); 595 if (!fin->fin_out || 596 !NET_IS_HCK_L3_FULL(net_data_p, fin->fin_m)) 597 fix_outcksum(&ip->ip_sum, sd); 598 } 599 #endif 600 601 /* 602 * For TCP packets, we may need to adjust the sequence and 603 * acknowledgement numbers to reflect changes in size of the 604 * data stream. 605 * 606 * For both TCP and UDP, recalculate the layer 4 checksum in 607 * software checksum case, as we can't tell if data has been 608 * changed or not. 609 */ 610 if (tcp != NULL) { 611 tcpudp = tcp; 612 csump = &tcp->th_sum; 613 (void) appr_fixseqack(fin, ip, aps, APR_INC(err)); 614 } else if (udp != NULL) { 615 tcpudp = udp; 616 csump = &udp->uh_sum; 617 } 618 619 if (tcpudp) { 620 #if SOLARIS && defined(_KERNEL) && (SOLARIS2 >= 6) && defined(MENTAT) 621 if (!fin->fin_out) { 622 /* 623 * We are incapable of adjusting partial hcksum 624 * result for inbound packets here, as the 625 * partial hcksum calculation range might not 626 * cover the whole payload, and the payload data 627 * might be changed by proxy. 628 */ 629 DB_CKSUMFLAGS(fin->fin_m) &= ~HCK_PARTIALCKSUM; 630 631 /* Inbound packets always need recalculation. */ 632 *csump = fr_cksum(fin->fin_qfm, ip, 633 fin->fin_p, tcpudp); 634 } else if (NET_IS_HCK_L4_PART(net_data_p, fin->fin_m)) { 635 if (err != 0) { 636 DB_CKSUMEND(fin->fin_m) += (short)err; 637 fix_incksum(csump, sd); 638 } 639 } else if (!NET_IS_HCK_L4_FULL(net_data_p, fin->fin_m)) 640 *csump = fr_cksum(fin->fin_qfm, ip, 641 fin->fin_p, tcpudp); 642 #else 643 *csump = fr_cksum(fin->fin_m, ip, fin->fin_p, tcpudp); 644 #endif 645 } 646 aps->aps_bytes += fin->fin_plen; 647 aps->aps_pkts++; 648 return 1; 649 } 650 return 0; 651 } 652 653 654 /* 655 * Search for an proxy by the protocol it is being used with and its name. 656 */ 657 aproxy_t *appr_lookup(pr, name, ifs) 658 u_int pr; 659 char *name; 660 ipf_stack_t *ifs; 661 { 662 aproxy_t *ap; 663 664 if (ipf_proxy_debug > 8) 665 printf("appr_lookup(%d,%s)\n", pr, name); 666 667 for (ap = ifs->ifs_ap_proxies; ap->apr_p; ap++) 668 if ((ap->apr_p == pr) && 669 !strncmp(name, ap->apr_label, sizeof(ap->apr_label))) { 670 ap->apr_ref++; 671 return ap; 672 } 673 674 for (ap = ifs->ifs_ap_proxylist; ap; ap = ap->apr_next) 675 if ((ap->apr_p == pr) && 676 !strncmp(name, ap->apr_label, sizeof(ap->apr_label))) { 677 ap->apr_ref++; 678 return ap; 679 } 680 if (ipf_proxy_debug > 2) 681 printf("appr_lookup: failed for %d/%s\n", pr, name); 682 return NULL; 683 } 684 685 686 void appr_free(ap) 687 aproxy_t *ap; 688 { 689 ap->apr_ref--; 690 } 691 692 693 void aps_free(aps, ifs) 694 ap_session_t *aps; 695 ipf_stack_t *ifs; 696 { 697 ap_session_t *a, **ap; 698 aproxy_t *apr; 699 700 if (!aps) 701 return; 702 703 for (ap = &ifs->ifs_ap_sess_list; ((a = *ap) != NULL); ap = &a->aps_next) 704 if (a == aps) { 705 *ap = a->aps_next; 706 break; 707 } 708 709 apr = aps->aps_apr; 710 if ((apr != NULL) && (apr->apr_del != NULL)) 711 (*apr->apr_del)(aps, apr->apr_private, ifs); 712 713 if ((aps->aps_data != NULL) && (aps->aps_psiz != 0)) 714 KFREES(aps->aps_data, aps->aps_psiz); 715 KFREE(aps); 716 } 717 718 719 /* 720 * returns 2 if ack or seq number in TCP header is changed, returns 0 otherwise 721 */ 722 static int appr_fixseqack(fin, ip, aps, inc) 723 fr_info_t *fin; 724 ip_t *ip; 725 ap_session_t *aps; 726 int inc; 727 { 728 int sel, ch = 0, out, nlen; 729 u_32_t seq1, seq2; 730 tcphdr_t *tcp; 731 short inc2; 732 733 tcp = (tcphdr_t *)fin->fin_dp; 734 out = fin->fin_out; 735 /* 736 * ip_len has already been adjusted by 'inc'. 737 */ 738 nlen = ip->ip_len; 739 nlen -= (IP_HL(ip) << 2) + (TCP_OFF(tcp) << 2); 740 741 inc2 = inc; 742 inc = (int)inc2; 743 744 if (out != 0) { 745 seq1 = (u_32_t)ntohl(tcp->th_seq); 746 sel = aps->aps_sel[out]; 747 748 /* switch to other set ? */ 749 if ((aps->aps_seqmin[!sel] > aps->aps_seqmin[sel]) && 750 (seq1 > aps->aps_seqmin[!sel])) { 751 if (ipf_proxy_debug > 7) 752 printf("proxy out switch set seq %d -> %d %x > %x\n", 753 sel, !sel, seq1, 754 aps->aps_seqmin[!sel]); 755 sel = aps->aps_sel[out] = !sel; 756 } 757 758 if (aps->aps_seqoff[sel]) { 759 seq2 = aps->aps_seqmin[sel] - aps->aps_seqoff[sel]; 760 if (seq1 > seq2) { 761 seq2 = aps->aps_seqoff[sel]; 762 seq1 += seq2; 763 tcp->th_seq = htonl(seq1); 764 ch = 1; 765 } 766 } 767 768 if (inc && (seq1 > aps->aps_seqmin[!sel])) { 769 aps->aps_seqmin[sel] = seq1 + nlen - 1; 770 aps->aps_seqoff[sel] = aps->aps_seqoff[sel] + inc; 771 if (ipf_proxy_debug > 7) 772 printf("proxy seq set %d at %x to %d + %d\n", 773 sel, aps->aps_seqmin[sel], 774 aps->aps_seqoff[sel], inc); 775 } 776 777 /***/ 778 779 seq1 = ntohl(tcp->th_ack); 780 sel = aps->aps_sel[1 - out]; 781 782 /* switch to other set ? */ 783 if ((aps->aps_ackmin[!sel] > aps->aps_ackmin[sel]) && 784 (seq1 > aps->aps_ackmin[!sel])) { 785 if (ipf_proxy_debug > 7) 786 printf("proxy out switch set ack %d -> %d %x > %x\n", 787 sel, !sel, seq1, 788 aps->aps_ackmin[!sel]); 789 sel = aps->aps_sel[1 - out] = !sel; 790 } 791 792 if (aps->aps_ackoff[sel] && (seq1 > aps->aps_ackmin[sel])) { 793 seq2 = aps->aps_ackoff[sel]; 794 tcp->th_ack = htonl(seq1 - seq2); 795 ch = 1; 796 } 797 } else { 798 seq1 = ntohl(tcp->th_seq); 799 sel = aps->aps_sel[out]; 800 801 /* switch to other set ? */ 802 if ((aps->aps_ackmin[!sel] > aps->aps_ackmin[sel]) && 803 (seq1 > aps->aps_ackmin[!sel])) { 804 if (ipf_proxy_debug > 7) 805 printf("proxy in switch set ack %d -> %d %x > %x\n", 806 sel, !sel, seq1, aps->aps_ackmin[!sel]); 807 sel = aps->aps_sel[out] = !sel; 808 } 809 810 if (aps->aps_ackoff[sel]) { 811 seq2 = aps->aps_ackmin[sel] - aps->aps_ackoff[sel]; 812 if (seq1 > seq2) { 813 seq2 = aps->aps_ackoff[sel]; 814 seq1 += seq2; 815 tcp->th_seq = htonl(seq1); 816 ch = 1; 817 } 818 } 819 820 if (inc && (seq1 > aps->aps_ackmin[!sel])) { 821 aps->aps_ackmin[!sel] = seq1 + nlen - 1; 822 aps->aps_ackoff[!sel] = aps->aps_ackoff[sel] + inc; 823 824 if (ipf_proxy_debug > 7) 825 printf("proxy ack set %d at %x to %d + %d\n", 826 !sel, aps->aps_seqmin[!sel], 827 aps->aps_seqoff[sel], inc); 828 } 829 830 /***/ 831 832 seq1 = ntohl(tcp->th_ack); 833 sel = aps->aps_sel[1 - out]; 834 835 /* switch to other set ? */ 836 if ((aps->aps_seqmin[!sel] > aps->aps_seqmin[sel]) && 837 (seq1 > aps->aps_seqmin[!sel])) { 838 if (ipf_proxy_debug > 7) 839 printf("proxy in switch set seq %d -> %d %x > %x\n", 840 sel, !sel, seq1, aps->aps_seqmin[!sel]); 841 sel = aps->aps_sel[1 - out] = !sel; 842 } 843 844 if (aps->aps_seqoff[sel] != 0) { 845 if (ipf_proxy_debug > 7) 846 printf("sel %d seqoff %d seq1 %x seqmin %x\n", 847 sel, aps->aps_seqoff[sel], seq1, 848 aps->aps_seqmin[sel]); 849 if (seq1 > aps->aps_seqmin[sel]) { 850 seq2 = aps->aps_seqoff[sel]; 851 tcp->th_ack = htonl(seq1 - seq2); 852 ch = 1; 853 } 854 } 855 } 856 857 if (ipf_proxy_debug > 8) 858 printf("appr_fixseqack: seq %x ack %x\n", 859 ntohl(tcp->th_seq), ntohl(tcp->th_ack)); 860 return ch ? 2 : 0; 861 } 862 863 864 /* 865 * Initialise hook for kernel application proxies. 866 * Call the initialise routine for all the compiled in kernel proxies. 867 */ 868 int appr_init(ifs) 869 ipf_stack_t *ifs; 870 { 871 aproxy_t *ap; 872 int err = 0; 873 874 /* Since the refcnt is used we make a copy of lcl_ap_proxies */ 875 KMALLOCS(ifs->ifs_ap_proxies, aproxy_t *, sizeof (lcl_ap_proxies)); 876 bcopy(lcl_ap_proxies, ifs->ifs_ap_proxies, sizeof (lcl_ap_proxies)); 877 878 for (ap = ifs->ifs_ap_proxies; ap->apr_p; ap++) { 879 if (ap->apr_init != NULL) { 880 err = (*ap->apr_init)(&ap->apr_private, ifs); 881 if (err != 0) 882 break; 883 } 884 } 885 return 0; 886 } 887 888 889 /* 890 * Unload hook for kernel application proxies. 891 * Call the finialise routine for all the compiled in kernel proxies. 892 */ 893 void appr_unload(ifs) 894 ipf_stack_t *ifs; 895 { 896 aproxy_t *ap; 897 if(ifs->ifs_ap_proxies == NULL) 898 return; 899 900 for (ap = ifs->ifs_ap_proxies; ap->apr_p; ap++) 901 if (ap->apr_fini != NULL) 902 (*ap->apr_fini)(&ap->apr_private, ifs); 903 for (ap = ifs->ifs_ap_proxylist; ap; ap = ap->apr_next) 904 if (ap->apr_fini != NULL) 905 (*ap->apr_fini)(&ap->apr_private, ifs); 906 907 KFREES(ifs->ifs_ap_proxies, sizeof (lcl_ap_proxies)); 908 ifs->ifs_ap_proxies = NULL; 909 } 910