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 defined(SOLARIS) && defined(_KERNEL) && (SOLARIS2 >= 6) && \ 475 defined(ICK_VALID) 476 mb_t *m; 477 int dosum = 1; 478 #endif 479 tcphdr_t *tcp = NULL; 480 udphdr_t *udp = NULL; 481 void *tcpudp = NULL; 482 u_short *csump; 483 ap_session_t *aps; 484 aproxy_t *apr; 485 ip_t *ip; 486 short rv; 487 int err; 488 #if !defined(_KERNEL) || defined(MENTAT) || defined(__sgi) 489 u_32_t s1, s2, sd; 490 #endif 491 ipf_stack_t *ifs = fin->fin_ifs; 492 493 #if defined(SOLARIS) && defined(_KERNEL) && (SOLARIS2 >= 6) 494 net_handle_t net_data_p; 495 if (fin->fin_v == 4) 496 net_data_p = ifs->ifs_ipf_ipv4; 497 else 498 net_data_p = ifs->ifs_ipf_ipv6; 499 #endif 500 501 if (fin->fin_flx & FI_BAD) { 502 if (ipf_proxy_debug > 0) 503 printf("appr_check: flx 0x%x (BAD)\n", fin->fin_flx); 504 return -1; 505 } 506 507 #ifndef IPFILTER_CKSUM 508 if ((fin->fin_out == 0) && (fr_checkl4sum(fin) == -1)) { 509 if (ipf_proxy_debug > 0) 510 printf("appr_check: l4 checksum failure %d\n", 511 fin->fin_p); 512 if (fin->fin_p == IPPROTO_TCP) 513 ifs->ifs_frstats[fin->fin_out].fr_tcpbad++; 514 return -1; 515 } 516 #endif 517 518 aps = nat->nat_aps; 519 if ((aps != NULL) && (aps->aps_p == fin->fin_p)) { 520 /* 521 * If there is data in this packet to be proxied then try and 522 * get it all into the one buffer, else drop it. 523 */ 524 #if defined(MENTAT) || defined(HAVE_M_PULLDOWN) 525 if ((fin->fin_dlen > 0) && !(fin->fin_flx & FI_COALESCE)) 526 if (fr_coalesce(fin) == -1) { 527 if (ipf_proxy_debug > 0) 528 printf("appr_check: fr_coalesce failed %x\n", fin->fin_flx); 529 return -1; 530 } 531 #endif 532 ip = fin->fin_ip; 533 534 switch (fin->fin_p) 535 { 536 case IPPROTO_TCP : 537 tcp = (tcphdr_t *)fin->fin_dp; 538 539 #if defined(SOLARIS) && defined(_KERNEL) && (SOLARIS2 >= 6) && \ 540 defined(ICK_VALID) 541 m = fin->fin_qfm; 542 if (dohwcksum && (m->b_ick_flag == ICK_VALID)) 543 dosum = 0; 544 #endif 545 /* 546 * Don't bother the proxy with these...or in fact, 547 * should we free up proxy stuff when seen? 548 */ 549 if ((fin->fin_tcpf & TH_RST) != 0) 550 break; 551 /*FALLTHROUGH*/ 552 case IPPROTO_UDP : 553 udp = (udphdr_t *)fin->fin_dp; 554 break; 555 default : 556 break; 557 } 558 559 apr = aps->aps_apr; 560 err = 0; 561 if (fin->fin_out != 0) { 562 if (apr->apr_outpkt != NULL) 563 err = (*apr->apr_outpkt)(fin, aps, nat, apr->apr_private); 564 } else { 565 if (apr->apr_inpkt != NULL) 566 err = (*apr->apr_inpkt)(fin, aps, nat, apr->apr_private); 567 } 568 569 rv = APR_EXIT(err); 570 if (((ipf_proxy_debug > 0) && (rv != 0)) || 571 (ipf_proxy_debug > 8)) 572 printf("appr_check: out %d err %x rv %d\n", 573 fin->fin_out, err, rv); 574 if (rv == 1) 575 return -1; 576 577 if (rv == 2) { 578 appr_free(apr); 579 nat->nat_aps = NULL; 580 return -1; 581 } 582 583 /* 584 * If err != 0 then the data size of the packet has changed 585 * so we need to recalculate the header checksums for the 586 * packet. 587 * inbound packets always need to be adjusted. 588 */ 589 #if !defined(_KERNEL) || defined(MENTAT) || defined(__sgi) 590 if (err != 0) { 591 short adjlen = err & 0xffff; 592 593 s1 = LONG_SUM(ip->ip_len - adjlen); 594 s2 = LONG_SUM(ip->ip_len); 595 CALC_SUMD(s1, s2, sd); 596 sd = (sd & 0xffff) + (sd >> 16); 597 if (!fin->fin_out || 598 !NET_IS_HCK_L3_FULL(net_data_p, fin->fin_m)) 599 fix_outcksum(&ip->ip_sum, sd); 600 } 601 #endif 602 603 /* 604 * For TCP packets, we may need to adjust the sequence and 605 * acknowledgement numbers to reflect changes in size of the 606 * data stream. 607 * 608 * For both TCP and UDP, recalculate the layer 4 checksum in 609 * software checksum case, as we can't tell if data has been 610 * changed or not. 611 */ 612 if (tcp != NULL) { 613 tcpudp = tcp; 614 csump = &tcp->th_sum; 615 (void) appr_fixseqack(fin, ip, aps, APR_INC(err)); 616 } else if (udp != NULL) { 617 tcpudp = udp; 618 csump = &udp->uh_sum; 619 } 620 621 if (tcpudp) { 622 #if defined(SOLARIS) && defined(_KERNEL) && (SOLARIS2 >= 6) && defined(MENTAT) 623 if (!fin->fin_out) { 624 /* 625 * We are incapable of adjusting partial hcksum 626 * result for inbound packets here, as the 627 * partial hcksum calculation range might not 628 * cover the whole payload, and the payload data 629 * might be changed by proxy. 630 */ 631 DB_CKSUMFLAGS(fin->fin_m) &= ~HCK_PARTIALCKSUM; 632 633 /* Inbound packets always need recalculation. */ 634 *csump = fr_cksum(fin->fin_qfm, ip, 635 fin->fin_p, tcpudp); 636 } else if (NET_IS_HCK_L4_PART(net_data_p, fin->fin_m)) { 637 if (err != 0) { 638 DB_CKSUMEND(fin->fin_m) += (short)err; 639 fix_incksum(csump, sd); 640 } 641 } else if (!NET_IS_HCK_L4_FULL(net_data_p, fin->fin_m)) 642 *csump = fr_cksum(fin->fin_qfm, ip, 643 fin->fin_p, tcpudp); 644 #else 645 *csump = fr_cksum(fin->fin_m, ip, fin->fin_p, tcpudp); 646 #endif 647 } 648 aps->aps_bytes += fin->fin_plen; 649 aps->aps_pkts++; 650 return 1; 651 } 652 return 0; 653 } 654 655 656 /* 657 * Search for an proxy by the protocol it is being used with and its name. 658 */ 659 aproxy_t *appr_lookup(pr, name, ifs) 660 u_int pr; 661 char *name; 662 ipf_stack_t *ifs; 663 { 664 aproxy_t *ap; 665 666 if (ipf_proxy_debug > 8) 667 printf("appr_lookup(%d,%s)\n", pr, name); 668 669 for (ap = ifs->ifs_ap_proxies; ap->apr_p; ap++) 670 if ((ap->apr_p == pr) && 671 !strncmp(name, ap->apr_label, sizeof(ap->apr_label))) { 672 ap->apr_ref++; 673 return ap; 674 } 675 676 for (ap = ifs->ifs_ap_proxylist; ap; ap = ap->apr_next) 677 if ((ap->apr_p == pr) && 678 !strncmp(name, ap->apr_label, sizeof(ap->apr_label))) { 679 ap->apr_ref++; 680 return ap; 681 } 682 if (ipf_proxy_debug > 2) 683 printf("appr_lookup: failed for %d/%s\n", pr, name); 684 return NULL; 685 } 686 687 688 void appr_free(ap) 689 aproxy_t *ap; 690 { 691 ap->apr_ref--; 692 } 693 694 695 void aps_free(aps, ifs) 696 ap_session_t *aps; 697 ipf_stack_t *ifs; 698 { 699 ap_session_t *a, **ap; 700 aproxy_t *apr; 701 702 if (!aps) 703 return; 704 705 for (ap = &ifs->ifs_ap_sess_list; ((a = *ap) != NULL); ap = &a->aps_next) 706 if (a == aps) { 707 *ap = a->aps_next; 708 break; 709 } 710 711 apr = aps->aps_apr; 712 if ((apr != NULL) && (apr->apr_del != NULL)) 713 (*apr->apr_del)(aps, apr->apr_private, ifs); 714 715 if ((aps->aps_data != NULL) && (aps->aps_psiz != 0)) 716 KFREES(aps->aps_data, aps->aps_psiz); 717 KFREE(aps); 718 } 719 720 721 /* 722 * returns 2 if ack or seq number in TCP header is changed, returns 0 otherwise 723 */ 724 static int appr_fixseqack(fin, ip, aps, inc) 725 fr_info_t *fin; 726 ip_t *ip; 727 ap_session_t *aps; 728 int inc; 729 { 730 int sel, ch = 0, out, nlen; 731 u_32_t seq1, seq2; 732 tcphdr_t *tcp; 733 short inc2; 734 735 tcp = (tcphdr_t *)fin->fin_dp; 736 out = fin->fin_out; 737 /* 738 * ip_len has already been adjusted by 'inc'. 739 */ 740 nlen = ip->ip_len; 741 nlen -= (IP_HL(ip) << 2) + (TCP_OFF(tcp) << 2); 742 743 inc2 = inc; 744 inc = (int)inc2; 745 746 if (out != 0) { 747 seq1 = (u_32_t)ntohl(tcp->th_seq); 748 sel = aps->aps_sel[out]; 749 750 /* switch to other set ? */ 751 if ((aps->aps_seqmin[!sel] > aps->aps_seqmin[sel]) && 752 (seq1 > aps->aps_seqmin[!sel])) { 753 if (ipf_proxy_debug > 7) 754 printf("proxy out switch set seq %d -> %d %x > %x\n", 755 sel, !sel, seq1, 756 aps->aps_seqmin[!sel]); 757 sel = aps->aps_sel[out] = !sel; 758 } 759 760 if (aps->aps_seqoff[sel]) { 761 seq2 = aps->aps_seqmin[sel] - aps->aps_seqoff[sel]; 762 if (seq1 > seq2) { 763 seq2 = aps->aps_seqoff[sel]; 764 seq1 += seq2; 765 tcp->th_seq = htonl(seq1); 766 ch = 1; 767 } 768 } 769 770 if (inc && (seq1 > aps->aps_seqmin[!sel])) { 771 aps->aps_seqmin[sel] = seq1 + nlen - 1; 772 aps->aps_seqoff[sel] = aps->aps_seqoff[sel] + inc; 773 if (ipf_proxy_debug > 7) 774 printf("proxy seq set %d at %x to %d + %d\n", 775 sel, aps->aps_seqmin[sel], 776 aps->aps_seqoff[sel], inc); 777 } 778 779 /***/ 780 781 seq1 = ntohl(tcp->th_ack); 782 sel = aps->aps_sel[1 - out]; 783 784 /* switch to other set ? */ 785 if ((aps->aps_ackmin[!sel] > aps->aps_ackmin[sel]) && 786 (seq1 > aps->aps_ackmin[!sel])) { 787 if (ipf_proxy_debug > 7) 788 printf("proxy out switch set ack %d -> %d %x > %x\n", 789 sel, !sel, seq1, 790 aps->aps_ackmin[!sel]); 791 sel = aps->aps_sel[1 - out] = !sel; 792 } 793 794 if (aps->aps_ackoff[sel] && (seq1 > aps->aps_ackmin[sel])) { 795 seq2 = aps->aps_ackoff[sel]; 796 tcp->th_ack = htonl(seq1 - seq2); 797 ch = 1; 798 } 799 } else { 800 seq1 = ntohl(tcp->th_seq); 801 sel = aps->aps_sel[out]; 802 803 /* switch to other set ? */ 804 if ((aps->aps_ackmin[!sel] > aps->aps_ackmin[sel]) && 805 (seq1 > aps->aps_ackmin[!sel])) { 806 if (ipf_proxy_debug > 7) 807 printf("proxy in switch set ack %d -> %d %x > %x\n", 808 sel, !sel, seq1, aps->aps_ackmin[!sel]); 809 sel = aps->aps_sel[out] = !sel; 810 } 811 812 if (aps->aps_ackoff[sel]) { 813 seq2 = aps->aps_ackmin[sel] - aps->aps_ackoff[sel]; 814 if (seq1 > seq2) { 815 seq2 = aps->aps_ackoff[sel]; 816 seq1 += seq2; 817 tcp->th_seq = htonl(seq1); 818 ch = 1; 819 } 820 } 821 822 if (inc && (seq1 > aps->aps_ackmin[!sel])) { 823 aps->aps_ackmin[!sel] = seq1 + nlen - 1; 824 aps->aps_ackoff[!sel] = aps->aps_ackoff[sel] + inc; 825 826 if (ipf_proxy_debug > 7) 827 printf("proxy ack set %d at %x to %d + %d\n", 828 !sel, aps->aps_seqmin[!sel], 829 aps->aps_seqoff[sel], inc); 830 } 831 832 /***/ 833 834 seq1 = ntohl(tcp->th_ack); 835 sel = aps->aps_sel[1 - out]; 836 837 /* switch to other set ? */ 838 if ((aps->aps_seqmin[!sel] > aps->aps_seqmin[sel]) && 839 (seq1 > aps->aps_seqmin[!sel])) { 840 if (ipf_proxy_debug > 7) 841 printf("proxy in switch set seq %d -> %d %x > %x\n", 842 sel, !sel, seq1, aps->aps_seqmin[!sel]); 843 sel = aps->aps_sel[1 - out] = !sel; 844 } 845 846 if (aps->aps_seqoff[sel] != 0) { 847 if (ipf_proxy_debug > 7) 848 printf("sel %d seqoff %d seq1 %x seqmin %x\n", 849 sel, aps->aps_seqoff[sel], seq1, 850 aps->aps_seqmin[sel]); 851 if (seq1 > aps->aps_seqmin[sel]) { 852 seq2 = aps->aps_seqoff[sel]; 853 tcp->th_ack = htonl(seq1 - seq2); 854 ch = 1; 855 } 856 } 857 } 858 859 if (ipf_proxy_debug > 8) 860 printf("appr_fixseqack: seq %x ack %x\n", 861 ntohl(tcp->th_seq), ntohl(tcp->th_ack)); 862 return ch ? 2 : 0; 863 } 864 865 866 /* 867 * Initialise hook for kernel application proxies. 868 * Call the initialise routine for all the compiled in kernel proxies. 869 */ 870 int appr_init(ifs) 871 ipf_stack_t *ifs; 872 { 873 aproxy_t *ap; 874 int err = 0; 875 876 /* Since the refcnt is used we make a copy of lcl_ap_proxies */ 877 KMALLOCS(ifs->ifs_ap_proxies, aproxy_t *, sizeof (lcl_ap_proxies)); 878 if (ifs->ifs_ap_proxies == NULL) 879 return (-1); 880 bcopy(lcl_ap_proxies, ifs->ifs_ap_proxies, sizeof (lcl_ap_proxies)); 881 882 for (ap = ifs->ifs_ap_proxies; ap->apr_p; ap++) { 883 if (ap->apr_init != NULL) { 884 err = (*ap->apr_init)(&ap->apr_private, ifs); 885 if (err != 0) 886 break; 887 } 888 } 889 return 0; 890 } 891 892 893 /* 894 * Unload hook for kernel application proxies. 895 * Call the finialise routine for all the compiled in kernel proxies. 896 */ 897 void appr_unload(ifs) 898 ipf_stack_t *ifs; 899 { 900 aproxy_t *ap; 901 if(ifs->ifs_ap_proxies == NULL) 902 return; 903 904 for (ap = ifs->ifs_ap_proxies; ap->apr_p; ap++) 905 if (ap->apr_fini != NULL) 906 (*ap->apr_fini)(&ap->apr_private, ifs); 907 for (ap = ifs->ifs_ap_proxylist; ap; ap = ap->apr_next) 908 if (ap->apr_fini != NULL) 909 (*ap->apr_fini)(&ap->apr_private, ifs); 910 911 KFREES(ifs->ifs_ap_proxies, sizeof (lcl_ap_proxies)); 912 ifs->ifs_ap_proxies = NULL; 913 } 914