| 1 | /* $NetBSD: ip_proxy.c,v 1.5 2012/07/22 16:34:04 darrenr Exp $ */ |
| 2 | |
| 3 | /* |
| 4 | * Copyright (C) 2012 by Darren Reed. |
| 5 | * |
| 6 | * See the IPFILTER.LICENCE file for details on licencing. |
| 7 | */ |
| 8 | #if defined(KERNEL) || defined(_KERNEL) |
| 9 | # undef KERNEL |
| 10 | # undef _KERNEL |
| 11 | # define KERNEL 1 |
| 12 | # define _KERNEL 1 |
| 13 | #endif |
| 14 | #include <sys/errno.h> |
| 15 | #include <sys/types.h> |
| 16 | #include <sys/param.h> |
| 17 | #include <sys/time.h> |
| 18 | #include <sys/file.h> |
| 19 | #if !defined(AIX) |
| 20 | # include <sys/fcntl.h> |
| 21 | #endif |
| 22 | #if !defined(_KERNEL) && !defined(__KERNEL__) |
| 23 | # include <stdio.h> |
| 24 | # include <string.h> |
| 25 | # include <stdlib.h> |
| 26 | # include <ctype.h> |
| 27 | # define _KERNEL |
| 28 | # ifdef __OpenBSD__ |
| 29 | struct file; |
| 30 | # endif |
| 31 | # include <sys/uio.h> |
| 32 | # undef _KERNEL |
| 33 | #endif |
| 34 | #if !defined(linux) |
| 35 | # include <sys/protosw.h> |
| 36 | #endif |
| 37 | #include <sys/socket.h> |
| 38 | #if defined(_KERNEL) |
| 39 | # if !defined(__NetBSD__) && !defined(sun) && !defined(__osf__) && \ |
| 40 | !defined(__OpenBSD__) && !defined(__hpux) && !defined(__sgi) && \ |
| 41 | !defined(AIX) |
| 42 | # include <sys/ctype.h> |
| 43 | # endif |
| 44 | # include <sys/systm.h> |
| 45 | # if !defined(__SVR4) && !defined(__svr4__) |
| 46 | # include <sys/mbuf.h> |
| 47 | # endif |
| 48 | #endif |
| 49 | #if defined(_KERNEL) && (__FreeBSD_version >= 220000) |
| 50 | # include <sys/filio.h> |
| 51 | # include <sys/fcntl.h> |
| 52 | #else |
| 53 | # include <sys/ioctl.h> |
| 54 | #endif |
| 55 | #if defined(__SVR4) || defined(__svr4__) |
| 56 | # include <sys/byteorder.h> |
| 57 | # ifdef _KERNEL |
| 58 | # include <sys/dditypes.h> |
| 59 | # endif |
| 60 | # include <sys/stream.h> |
| 61 | # include <sys/kmem.h> |
| 62 | #endif |
| 63 | #if __FreeBSD__ > 2 |
| 64 | # include <sys/queue.h> |
| 65 | #endif |
| 66 | #include <net/if.h> |
| 67 | #ifdef sun |
| 68 | # include <net/af.h> |
| 69 | #endif |
| 70 | #include <netinet/in.h> |
| 71 | #include <netinet/in_systm.h> |
| 72 | #include <netinet/ip.h> |
| 73 | #ifndef linux |
| 74 | # include <netinet/ip_var.h> |
| 75 | #endif |
| 76 | #include <netinet/tcp.h> |
| 77 | #include <netinet/udp.h> |
| 78 | #include <netinet/ip_icmp.h> |
| 79 | #include "netinet/ip_compat.h" |
| 80 | #include <netinet/tcpip.h> |
| 81 | #include "netinet/ip_fil.h" |
| 82 | #include "netinet/ip_nat.h" |
| 83 | #include "netinet/ip_state.h" |
| 84 | #include "netinet/ip_proxy.h" |
| 85 | #if (__FreeBSD_version >= 300000) |
| 86 | # include <sys/malloc.h> |
| 87 | #endif |
| 88 | |
| 89 | /* END OF INCLUDES */ |
| 90 | |
| 91 | #include "netinet/ip_dns_pxy.c" |
| 92 | #include "netinet/ip_ftp_pxy.c" |
| 93 | #include "netinet/ip_tftp_pxy.c" |
| 94 | #include "netinet/ip_rcmd_pxy.c" |
| 95 | #include "netinet/ip_pptp_pxy.c" |
| 96 | #if defined(_KERNEL) |
| 97 | # include "netinet/ip_irc_pxy.c" |
| 98 | # include "netinet/ip_raudio_pxy.c" |
| 99 | # include "netinet/ip_netbios_pxy.c" |
| 100 | #endif |
| 101 | #include "netinet/ip_ipsec_pxy.c" |
| 102 | #include "netinet/ip_rpcb_pxy.c" |
| 103 | |
| 104 | #if !defined(lint) |
| 105 | #if defined(__NetBSD__) |
| 106 | #include <sys/cdefs.h> |
| 107 | __KERNEL_RCSID(0, "$NetBSD: ip_proxy.c,v 1.5 2012/07/22 16:34:04 darrenr Exp $" ); |
| 108 | #else |
| 109 | static const char rcsid[] = "@(#)Id: ip_proxy.c,v 1.1.1.2 2012/07/22 13:45:33 darrenr Exp" ; |
| 110 | #endif |
| 111 | #endif |
| 112 | |
| 113 | #define AP_SESS_SIZE 53 |
| 114 | |
| 115 | static int ipf_proxy_fixseqack(fr_info_t *, ip_t *, ap_session_t *, int ); |
| 116 | static aproxy_t *ipf_proxy_create_clone(ipf_main_softc_t *, aproxy_t *); |
| 117 | |
| 118 | typedef struct ipf_proxy_softc_s { |
| 119 | int ips_proxy_debug; |
| 120 | int ips_proxy_session_size; |
| 121 | ap_session_t **ips_sess_tab; |
| 122 | ap_session_t *ips_sess_list; |
| 123 | aproxy_t *ips_proxies; |
| 124 | int ips_init_run; |
| 125 | ipftuneable_t *ipf_proxy_tune; |
| 126 | } ipf_proxy_softc_t; |
| 127 | |
| 128 | static ipftuneable_t ipf_proxy_tuneables[] = { |
| 129 | { { (void *)offsetof(ipf_proxy_softc_t, ips_proxy_debug) }, |
| 130 | "proxy_debug" , 0, 0x1f, |
| 131 | stsizeof(ipf_proxy_softc_t, ips_proxy_debug), |
| 132 | 0, NULL, NULL }, |
| 133 | { { NULL }, NULL, 0, 0, |
| 134 | 0, |
| 135 | 0, NULL, NULL} |
| 136 | }; |
| 137 | |
| 138 | static aproxy_t *ap_proxylist = NULL; |
| 139 | static aproxy_t ips_proxies[] = { |
| 140 | #ifdef IPF_FTP_PROXY |
| 141 | { NULL, NULL, "ftp" , (char)IPPROTO_TCP, 0, 0, 0, |
| 142 | ipf_p_ftp_main_load, ipf_p_ftp_main_unload, |
| 143 | ipf_p_ftp_soft_create, ipf_p_ftp_soft_destroy, |
| 144 | NULL, NULL, |
| 145 | ipf_p_ftp_new, ipf_p_ftp_del, ipf_p_ftp_in, ipf_p_ftp_out, NULL, |
| 146 | NULL, NULL, NULL, NULL }, |
| 147 | #endif |
| 148 | #ifdef IPF_TFTP_PROXY |
| 149 | { NULL, NULL, "tftp" , (char)IPPROTO_UDP, 0, 0, 0, |
| 150 | ipf_p_tftp_main_load, ipf_p_tftp_main_unload, |
| 151 | ipf_p_tftp_soft_create, ipf_p_tftp_soft_destroy, |
| 152 | NULL, NULL, |
| 153 | ipf_p_tftp_new, ipf_p_tftp_del, |
| 154 | ipf_p_tftp_in, ipf_p_tftp_out, NULL, |
| 155 | NULL, NULL, NULL, NULL }, |
| 156 | #endif |
| 157 | #ifdef IPF_IRC_PROXY |
| 158 | { NULL, NULL, "irc" , (char)IPPROTO_TCP, 0, 0, 0, |
| 159 | ipf_p_irc_main_load, ipf_p_irc_main_unload, |
| 160 | NULL, NULL, |
| 161 | NULL, NULL, |
| 162 | ipf_p_irc_new, NULL, NULL, ipf_p_irc_out, NULL, |
| 163 | NULL, NULL, NULL, NULL }, |
| 164 | #endif |
| 165 | #ifdef IPF_RCMD_PROXY |
| 166 | { NULL, NULL, "rcmd" , (char)IPPROTO_TCP, 0, 0, 0, |
| 167 | ipf_p_rcmd_main_load, ipf_p_rcmd_main_unload, |
| 168 | NULL, NULL, |
| 169 | NULL, NULL, |
| 170 | ipf_p_rcmd_new, ipf_p_rcmd_del, |
| 171 | ipf_p_rcmd_in, ipf_p_rcmd_out, NULL, |
| 172 | NULL, NULL, NULL, NULL }, |
| 173 | #endif |
| 174 | #ifdef IPF_RAUDIO_PROXY |
| 175 | { NULL, NULL, "raudio" , (char)IPPROTO_TCP, 0, 0, 0, |
| 176 | ipf_p_raudio_main_load, ipf_p_raudio_main_unload, |
| 177 | NULL, NULL, |
| 178 | NULL, NULL, |
| 179 | ipf_p_raudio_new, NULL, ipf_p_raudio_in, ipf_p_raudio_out, NULL, |
| 180 | NULL, NULL, NULL, NULL }, |
| 181 | #endif |
| 182 | #ifdef IPF_MSNRPC_PROXY |
| 183 | { NULL, NULL, "msnrpc" , (char)IPPROTO_TCP, 0, 0, 0, |
| 184 | ipf_p_msnrpc_init, ipf_p_msnrpc_fini, |
| 185 | NULL, NULL, |
| 186 | NULL, NULL, |
| 187 | ipf_p_msnrpc_new, NULL, ipf_p_msnrpc_in, ipf_p_msnrpc_out, NULL, |
| 188 | NULL, NULL, NULL, NULL }, |
| 189 | #endif |
| 190 | #ifdef IPF_NETBIOS_PROXY |
| 191 | { NULL, NULL, "netbios" , (char)IPPROTO_UDP, 0, 0, 0, |
| 192 | ipf_p_netbios_main_load, ipf_p_netbios_main_unload, |
| 193 | NULL, NULL, |
| 194 | NULL, NULL, |
| 195 | NULL, NULL, NULL, ipf_p_netbios_out, NULL, |
| 196 | NULL, NULL, NULL, NULL }, |
| 197 | #endif |
| 198 | #ifdef IPF_IPSEC_PROXY |
| 199 | { NULL, NULL, "ipsec" , (char)IPPROTO_UDP, 0, 0, 0, |
| 200 | NULL, NULL, |
| 201 | ipf_p_ipsec_soft_create, ipf_p_ipsec_soft_destroy, |
| 202 | ipf_p_ipsec_soft_init, ipf_p_ipsec_soft_fini, |
| 203 | ipf_p_ipsec_new, ipf_p_ipsec_del, |
| 204 | ipf_p_ipsec_inout, ipf_p_ipsec_inout, ipf_p_ipsec_match, |
| 205 | NULL, NULL, NULL, NULL }, |
| 206 | #endif |
| 207 | #ifdef IPF_DNS_PROXY |
| 208 | { NULL, NULL, "dns" , (char)IPPROTO_UDP, 0, 0, 0, |
| 209 | NULL, NULL, |
| 210 | ipf_p_dns_soft_create, ipf_p_dns_soft_destroy, |
| 211 | NULL, NULL, |
| 212 | ipf_p_dns_new, ipf_p_ipsec_del, |
| 213 | ipf_p_dns_inout, ipf_p_dns_inout, ipf_p_dns_match, |
| 214 | ipf_p_dns_ctl, NULL, NULL, NULL }, |
| 215 | #endif |
| 216 | #ifdef IPF_PPTP_PROXY |
| 217 | { NULL, NULL, "pptp" , (char)IPPROTO_TCP, 0, 0, 0, |
| 218 | ipf_p_pptp_main_load, ipf_p_pptp_main_unload, |
| 219 | NULL, NULL, |
| 220 | NULL, NULL, |
| 221 | ipf_p_pptp_new, ipf_p_pptp_del, |
| 222 | ipf_p_pptp_inout, ipf_p_pptp_inout, NULL, |
| 223 | NULL, NULL, NULL, NULL }, |
| 224 | #endif |
| 225 | #ifdef IPF_H323_PROXY |
| 226 | { NULL, NULL, "h323" , (char)IPPROTO_TCP, 0, 0, 0, |
| 227 | ipf_p_h323_main_load, ipf_p_h323_main_unload, |
| 228 | NULL, NULL, |
| 229 | NULL, NULL, |
| 230 | ipf_p_h323_new, ipf_p_h323_del, |
| 231 | ipf_p_h323_in, NULL, NULL, |
| 232 | NULL, NULL, NULL, NULL }, |
| 233 | { NULL, NULL, "h245" , (char)IPPROTO_TCP, 0, 0, 0, NULL, NULL, |
| 234 | NULL, NULL, |
| 235 | NULL, NULL, |
| 236 | ipf_p_h245_new, NULL, |
| 237 | NULL, ipf_p_h245_out, NULL, |
| 238 | NULL, NULL, NULL, NULL }, |
| 239 | #endif |
| 240 | #ifdef IPF_RPCB_PROXY |
| 241 | # ifndef _KERNEL |
| 242 | { NULL, NULL, "rpcbt" , (char)IPPROTO_TCP, 0, 0, 0, |
| 243 | NULL, NULL, |
| 244 | NULL, NULL, |
| 245 | NULL, NULL, |
| 246 | ipf_p_rpcb_new, ipf_p_rpcb_del, |
| 247 | ipf_p_rpcb_in, ipf_p_rpcb_out, NULL, |
| 248 | NULL, NULL, NULL, NULL }, |
| 249 | # endif |
| 250 | { NULL, NULL, "rpcbu" , (char)IPPROTO_UDP, 0, 0, 0, |
| 251 | ipf_p_rpcb_main_load, ipf_p_rpcb_main_unload, |
| 252 | NULL, NULL, |
| 253 | NULL, NULL, |
| 254 | ipf_p_rpcb_new, ipf_p_rpcb_del, |
| 255 | ipf_p_rpcb_in, ipf_p_rpcb_out, NULL, |
| 256 | NULL, NULL, NULL, NULL }, |
| 257 | #endif |
| 258 | { NULL, NULL, "" , '\0', 0, 0, 0, |
| 259 | NULL, NULL, |
| 260 | NULL, NULL, |
| 261 | NULL, NULL, |
| 262 | NULL, NULL, |
| 263 | NULL, NULL, NULL, |
| 264 | NULL, NULL, NULL, NULL } |
| 265 | }; |
| 266 | |
| 267 | |
| 268 | /* ------------------------------------------------------------------------ */ |
| 269 | /* Function: ipf_proxy_main_load */ |
| 270 | /* Returns: int - 0 == success, else failure. */ |
| 271 | /* Parameters: Nil */ |
| 272 | /* */ |
| 273 | /* Initialise hook for kernel application proxies. */ |
| 274 | /* Call the initialise routine for all the compiled in kernel proxies. */ |
| 275 | /* ------------------------------------------------------------------------ */ |
| 276 | int |
| 277 | ipf_proxy_main_load(void) |
| 278 | { |
| 279 | aproxy_t *ap; |
| 280 | |
| 281 | for (ap = ips_proxies; ap->apr_p; ap++) { |
| 282 | if (ap->apr_load != NULL) |
| 283 | (*ap->apr_load)(); |
| 284 | } |
| 285 | return 0; |
| 286 | } |
| 287 | |
| 288 | |
| 289 | /* ------------------------------------------------------------------------ */ |
| 290 | /* Function: ipf_proxy_main_unload */ |
| 291 | /* Returns: int - 0 == success, else failure. */ |
| 292 | /* Parameters: Nil */ |
| 293 | /* */ |
| 294 | /* Unload hook for kernel application proxies. */ |
| 295 | /* Call the finialise routine for all the compiled in kernel proxies. */ |
| 296 | /* ------------------------------------------------------------------------ */ |
| 297 | int |
| 298 | ipf_proxy_main_unload(void) |
| 299 | { |
| 300 | aproxy_t *ap; |
| 301 | |
| 302 | for (ap = ips_proxies; ap->apr_p; ap++) |
| 303 | if (ap->apr_unload != NULL) |
| 304 | (*ap->apr_unload)(); |
| 305 | for (ap = ap_proxylist; ap; ap = ap->apr_next) |
| 306 | if (ap->apr_unload != NULL) |
| 307 | (*ap->apr_unload)(); |
| 308 | |
| 309 | return 0; |
| 310 | } |
| 311 | |
| 312 | |
| 313 | /* ------------------------------------------------------------------------ */ |
| 314 | /* Function: ipf_proxy_soft_create */ |
| 315 | /* Returns: void * - */ |
| 316 | /* Parameters: softc(I) - pointer to soft context main structure */ |
| 317 | /* */ |
| 318 | /* Build the structure to hold all of the run time data to support proxies. */ |
| 319 | /* ------------------------------------------------------------------------ */ |
| 320 | void * |
| 321 | ipf_proxy_soft_create(ipf_main_softc_t *softc) |
| 322 | { |
| 323 | ipf_proxy_softc_t *softp; |
| 324 | aproxy_t *last; |
| 325 | aproxy_t *apn; |
| 326 | aproxy_t *ap; |
| 327 | |
| 328 | KMALLOC(softp, ipf_proxy_softc_t *); |
| 329 | if (softp == NULL) |
| 330 | return softp; |
| 331 | |
| 332 | bzero((char *)softp, sizeof(*softp)); |
| 333 | |
| 334 | #if defined(_KERNEL) |
| 335 | softp->ips_proxy_debug = 0; |
| 336 | #else |
| 337 | softp->ips_proxy_debug = 2; |
| 338 | #endif |
| 339 | softp->ips_proxy_session_size = AP_SESS_SIZE; |
| 340 | |
| 341 | softp->ipf_proxy_tune = ipf_tune_array_copy(softp, |
| 342 | sizeof(ipf_proxy_tuneables), |
| 343 | ipf_proxy_tuneables); |
| 344 | if (softp->ipf_proxy_tune == NULL) { |
| 345 | ipf_proxy_soft_destroy(softc, softp); |
| 346 | return NULL; |
| 347 | } |
| 348 | if (ipf_tune_array_link(softc, softp->ipf_proxy_tune) == -1) { |
| 349 | ipf_proxy_soft_destroy(softc, softp); |
| 350 | return NULL; |
| 351 | } |
| 352 | |
| 353 | last = NULL; |
| 354 | for (ap = ips_proxies; ap->apr_p; ap++) { |
| 355 | apn = ipf_proxy_create_clone(softc, ap); |
| 356 | if (apn == NULL) |
| 357 | goto failed; |
| 358 | if (last != NULL) |
| 359 | last->apr_next = apn; |
| 360 | else |
| 361 | softp->ips_proxies = apn; |
| 362 | last = apn; |
| 363 | } |
| 364 | for (ap = ips_proxies; ap != NULL; ap = ap->apr_next) { |
| 365 | apn = ipf_proxy_create_clone(softc, ap); |
| 366 | if (apn == NULL) |
| 367 | goto failed; |
| 368 | if (last != NULL) |
| 369 | last->apr_next = apn; |
| 370 | else |
| 371 | softp->ips_proxies = apn; |
| 372 | last = apn; |
| 373 | } |
| 374 | |
| 375 | return softp; |
| 376 | failed: |
| 377 | ipf_proxy_soft_destroy(softc, softp); |
| 378 | return NULL; |
| 379 | } |
| 380 | |
| 381 | |
| 382 | /* ------------------------------------------------------------------------ */ |
| 383 | /* Function: ipf_proxy_soft_create */ |
| 384 | /* Returns: void * - */ |
| 385 | /* Parameters: softc(I) - pointer to soft context main structure */ |
| 386 | /* orig(I) - pointer to proxy definition to copy */ |
| 387 | /* */ |
| 388 | /* This function clones a proxy definition given by orig and returns a */ |
| 389 | /* a pointer to that copy. */ |
| 390 | /* ------------------------------------------------------------------------ */ |
| 391 | static aproxy_t * |
| 392 | ipf_proxy_create_clone(ipf_main_softc_t *softc, aproxy_t *orig) |
| 393 | { |
| 394 | aproxy_t *apn; |
| 395 | |
| 396 | KMALLOC(apn, aproxy_t *); |
| 397 | if (apn == NULL) |
| 398 | return NULL; |
| 399 | |
| 400 | bcopy((char *)orig, (char *)apn, sizeof(*apn)); |
| 401 | apn->apr_next = NULL; |
| 402 | apn->apr_soft = NULL; |
| 403 | |
| 404 | if (apn->apr_create != NULL) { |
| 405 | apn->apr_soft = (*apn->apr_create)(softc); |
| 406 | if (apn->apr_soft == NULL) { |
| 407 | KFREE(apn); |
| 408 | return NULL; |
| 409 | } |
| 410 | } |
| 411 | |
| 412 | apn->apr_parent = orig; |
| 413 | orig->apr_clones++; |
| 414 | |
| 415 | return apn; |
| 416 | } |
| 417 | |
| 418 | |
| 419 | /* ------------------------------------------------------------------------ */ |
| 420 | /* Function: ipf_proxy_soft_create */ |
| 421 | /* Returns: int - 0 == success, else failure. */ |
| 422 | /* Parameters: softc(I) - pointer to soft context main structure */ |
| 423 | /* arg(I) - pointer to proxy contect data */ |
| 424 | /* */ |
| 425 | /* Initialise the proxy context and walk through each of the proxies and */ |
| 426 | /* call its initialisation function. This allows for proxies to do any */ |
| 427 | /* local setup prior to actual use. */ |
| 428 | /* ------------------------------------------------------------------------ */ |
| 429 | int |
| 430 | ipf_proxy_soft_init(ipf_main_softc_t *softc, void *arg) |
| 431 | { |
| 432 | ipf_proxy_softc_t *softp; |
| 433 | aproxy_t *ap; |
| 434 | u_int size; |
| 435 | int err; |
| 436 | |
| 437 | softp = arg; |
| 438 | size = softp->ips_proxy_session_size * sizeof(ap_session_t *); |
| 439 | |
| 440 | KMALLOCS(softp->ips_sess_tab, ap_session_t **, size); |
| 441 | |
| 442 | if (softp->ips_sess_tab == NULL) |
| 443 | return -1; |
| 444 | |
| 445 | bzero(softp->ips_sess_tab, size); |
| 446 | |
| 447 | for (ap = softp->ips_proxies; ap != NULL; ap = ap->apr_next) { |
| 448 | if (ap->apr_init != NULL) { |
| 449 | err = (*ap->apr_init)(softc, ap->apr_soft); |
| 450 | if (err != 0) |
| 451 | return -2; |
| 452 | } |
| 453 | } |
| 454 | softp->ips_init_run = 1; |
| 455 | |
| 456 | return 0; |
| 457 | } |
| 458 | |
| 459 | |
| 460 | /* ------------------------------------------------------------------------ */ |
| 461 | /* Function: ipf_proxy_soft_create */ |
| 462 | /* Returns: int - 0 == success, else failure. */ |
| 463 | /* Parameters: softc(I) - pointer to soft context main structure */ |
| 464 | /* arg(I) - pointer to proxy contect data */ |
| 465 | /* */ |
| 466 | /* This function should always succeed. It is responsible for ensuring that */ |
| 467 | /* the proxy context can be safely called when ipf_proxy_soft_destroy is */ |
| 468 | /* called and suring all of the proxies have similarly been instructed. */ |
| 469 | /* ------------------------------------------------------------------------ */ |
| 470 | int |
| 471 | ipf_proxy_soft_fini(ipf_main_softc_t *softc, void *arg) |
| 472 | { |
| 473 | ipf_proxy_softc_t *softp = arg; |
| 474 | aproxy_t *ap; |
| 475 | |
| 476 | for (ap = softp->ips_proxies; ap != NULL; ap = ap->apr_next) { |
| 477 | if (ap->apr_fini != NULL) { |
| 478 | (*ap->apr_fini)(softc, ap->apr_soft); |
| 479 | } |
| 480 | } |
| 481 | |
| 482 | if (softp->ips_sess_tab != NULL) { |
| 483 | KFREES(softp->ips_sess_tab, |
| 484 | softp->ips_proxy_session_size * sizeof(ap_session_t *)); |
| 485 | softp->ips_sess_tab = NULL; |
| 486 | } |
| 487 | softp->ips_init_run = 0; |
| 488 | |
| 489 | return 0; |
| 490 | } |
| 491 | |
| 492 | |
| 493 | /* ------------------------------------------------------------------------ */ |
| 494 | /* Function: ipf_proxy_soft_destroy */ |
| 495 | /* Returns: Nil */ |
| 496 | /* Parameters: softc(I) - pointer to soft context main structure */ |
| 497 | /* arg(I) - pointer to proxy contect data */ |
| 498 | /* */ |
| 499 | /* Free up all of the local data structures allocated during creation. */ |
| 500 | /* ------------------------------------------------------------------------ */ |
| 501 | void |
| 502 | ipf_proxy_soft_destroy(ipf_main_softc_t *softc, void *arg) |
| 503 | { |
| 504 | ipf_proxy_softc_t *softp = arg; |
| 505 | aproxy_t *ap; |
| 506 | |
| 507 | while ((ap = softp->ips_proxies) != NULL) { |
| 508 | softp->ips_proxies = ap->apr_next; |
| 509 | if (ap->apr_destroy != NULL) |
| 510 | (*ap->apr_destroy)(softc, ap->apr_soft); |
| 511 | ap->apr_parent->apr_clones--; |
| 512 | KFREE(ap); |
| 513 | } |
| 514 | |
| 515 | if (softp->ipf_proxy_tune != NULL) { |
| 516 | ipf_tune_array_unlink(softc, softp->ipf_proxy_tune); |
| 517 | KFREES(softp->ipf_proxy_tune, sizeof(ipf_proxy_tuneables)); |
| 518 | softp->ipf_proxy_tune = NULL; |
| 519 | } |
| 520 | |
| 521 | KFREE(softp); |
| 522 | } |
| 523 | |
| 524 | |
| 525 | /* ------------------------------------------------------------------------ */ |
| 526 | /* Function: ipf_proxy_flush */ |
| 527 | /* Returns: Nil */ |
| 528 | /* Parameters: arg(I) - pointer to proxy contect data */ |
| 529 | /* how(I) - indicates the type of flush operation */ |
| 530 | /* */ |
| 531 | /* Walk through all of the proxies and pass on the flush command as either */ |
| 532 | /* a flush or a clear. */ |
| 533 | /* ------------------------------------------------------------------------ */ |
| 534 | void |
| 535 | ipf_proxy_flush(void *arg, int how) |
| 536 | { |
| 537 | ipf_proxy_softc_t *softp = arg; |
| 538 | aproxy_t *ap; |
| 539 | |
| 540 | switch (how) |
| 541 | { |
| 542 | case 0 : |
| 543 | for (ap = softp->ips_proxies; ap; ap = ap->apr_next) |
| 544 | if (ap->apr_flush != NULL) |
| 545 | (*ap->apr_flush)(ap, how); |
| 546 | break; |
| 547 | case 1 : |
| 548 | for (ap = softp->ips_proxies; ap; ap = ap->apr_next) |
| 549 | if (ap->apr_clear != NULL) |
| 550 | (*ap->apr_clear)(ap); |
| 551 | break; |
| 552 | default : |
| 553 | break; |
| 554 | } |
| 555 | } |
| 556 | |
| 557 | |
| 558 | /* ------------------------------------------------------------------------ */ |
| 559 | /* Function: ipf_proxy_add */ |
| 560 | /* Returns: int - 0 == success, else failure. */ |
| 561 | /* Parameters: ap(I) - pointer to proxy structure */ |
| 562 | /* */ |
| 563 | /* Dynamically add a new kernel proxy. Ensure that it is unique in the */ |
| 564 | /* collection compiled in and dynamically added. */ |
| 565 | /* ------------------------------------------------------------------------ */ |
| 566 | int |
| 567 | ipf_proxy_add(void *arg, aproxy_t *ap) |
| 568 | { |
| 569 | ipf_proxy_softc_t *softp = arg; |
| 570 | |
| 571 | aproxy_t *a; |
| 572 | |
| 573 | for (a = ips_proxies; a->apr_p; a++) |
| 574 | if ((a->apr_p == ap->apr_p) && |
| 575 | !strncmp(a->apr_label, ap->apr_label, |
| 576 | sizeof(ap->apr_label))) { |
| 577 | if (softp->ips_proxy_debug & 0x01) |
| 578 | printf("ipf_proxy_add: %s/%d present (B)\n" , |
| 579 | a->apr_label, a->apr_p); |
| 580 | return -1; |
| 581 | } |
| 582 | |
| 583 | for (a = ap_proxylist; (a != NULL); a = a->apr_next) |
| 584 | if ((a->apr_p == ap->apr_p) && |
| 585 | !strncmp(a->apr_label, ap->apr_label, |
| 586 | sizeof(ap->apr_label))) { |
| 587 | if (softp->ips_proxy_debug & 0x01) |
| 588 | printf("ipf_proxy_add: %s/%d present (D)\n" , |
| 589 | a->apr_label, a->apr_p); |
| 590 | return -1; |
| 591 | } |
| 592 | ap->apr_next = ap_proxylist; |
| 593 | ap_proxylist = ap; |
| 594 | if (ap->apr_load != NULL) |
| 595 | (*ap->apr_load)(); |
| 596 | return 0; |
| 597 | } |
| 598 | |
| 599 | |
| 600 | /* ------------------------------------------------------------------------ */ |
| 601 | /* Function: ipf_proxy_ctl */ |
| 602 | /* Returns: int - 0 == success, else error */ |
| 603 | /* Parameters: softc(I) - pointer to soft context main structure */ |
| 604 | /* arg(I) - pointer to proxy context */ |
| 605 | /* ctl(I) - pointer to proxy control structure */ |
| 606 | /* */ |
| 607 | /* Check to see if the proxy this control request has come through for */ |
| 608 | /* exists, and if it does and it has a control function then invoke that */ |
| 609 | /* control function. */ |
| 610 | /* ------------------------------------------------------------------------ */ |
| 611 | int |
| 612 | ipf_proxy_ctl(ipf_main_softc_t *softc, void *arg, ap_ctl_t *ctl) |
| 613 | { |
| 614 | ipf_proxy_softc_t *softp = arg; |
| 615 | aproxy_t *a; |
| 616 | int error; |
| 617 | |
| 618 | a = ipf_proxy_lookup(arg, ctl->apc_p, ctl->apc_label); |
| 619 | if (a == NULL) { |
| 620 | if (softp->ips_proxy_debug & 0x01) |
| 621 | printf("ipf_proxy_ctl: can't find %s/%d\n" , |
| 622 | ctl->apc_label, ctl->apc_p); |
| 623 | IPFERROR(80001); |
| 624 | error = ESRCH; |
| 625 | } else if (a->apr_ctl == NULL) { |
| 626 | if (softp->ips_proxy_debug & 0x01) |
| 627 | printf("ipf_proxy_ctl: no ctl function for %s/%d\n" , |
| 628 | ctl->apc_label, ctl->apc_p); |
| 629 | IPFERROR(80002); |
| 630 | error = ENXIO; |
| 631 | } else { |
| 632 | error = (*a->apr_ctl)(softc, a->apr_soft, ctl); |
| 633 | if ((error != 0) && (softp->ips_proxy_debug & 0x02)) |
| 634 | printf("ipf_proxy_ctl: %s/%d ctl error %d\n" , |
| 635 | a->apr_label, a->apr_p, error); |
| 636 | } |
| 637 | return error; |
| 638 | } |
| 639 | |
| 640 | |
| 641 | /* ------------------------------------------------------------------------ */ |
| 642 | /* Function: ipf_proxy_del */ |
| 643 | /* Returns: int - 0 == success, else failure. */ |
| 644 | /* Parameters: ap(I) - pointer to proxy structure */ |
| 645 | /* */ |
| 646 | /* Delete a proxy that has been added dynamically from those available. */ |
| 647 | /* If it is in use, return 1 (do not destroy NOW), not in use 0 or -1 */ |
| 648 | /* if it cannot be matched. */ |
| 649 | /* ------------------------------------------------------------------------ */ |
| 650 | int |
| 651 | ipf_proxy_del(aproxy_t *ap) |
| 652 | { |
| 653 | aproxy_t *a, **app; |
| 654 | |
| 655 | for (app = &ap_proxylist; ((a = *app) != NULL); app = &a->apr_next) { |
| 656 | if (a == ap) { |
| 657 | a->apr_flags |= APR_DELETE; |
| 658 | if (ap->apr_ref == 0 && ap->apr_clones == 0) { |
| 659 | *app = a->apr_next; |
| 660 | return 0; |
| 661 | } |
| 662 | return 1; |
| 663 | } |
| 664 | } |
| 665 | |
| 666 | return -1; |
| 667 | } |
| 668 | |
| 669 | |
| 670 | /* ------------------------------------------------------------------------ */ |
| 671 | /* Function: ipf_proxy_ok */ |
| 672 | /* Returns: int - 1 == good match else not. */ |
| 673 | /* Parameters: fin(I) - pointer to packet information */ |
| 674 | /* tcp(I) - pointer to TCP/UDP header */ |
| 675 | /* nat(I) - pointer to current NAT session */ |
| 676 | /* */ |
| 677 | /* This function extends the NAT matching to ensure that a packet that has */ |
| 678 | /* arrived matches the proxy information attached to the NAT rule. Notably, */ |
| 679 | /* if the proxy is scheduled to be deleted then packets will not match the */ |
| 680 | /* rule even if the rule is still active. */ |
| 681 | /* ------------------------------------------------------------------------ */ |
| 682 | int |
| 683 | ipf_proxy_ok(fr_info_t *fin, tcphdr_t *tcp, ipnat_t *np) |
| 684 | { |
| 685 | aproxy_t *apr = np->in_apr; |
| 686 | u_short dport = np->in_odport; |
| 687 | |
| 688 | if ((apr == NULL) || (apr->apr_flags & APR_DELETE) || |
| 689 | (fin->fin_p != apr->apr_p)) |
| 690 | return 0; |
| 691 | if ((tcp == NULL) && dport) |
| 692 | return 0; |
| 693 | return 1; |
| 694 | } |
| 695 | |
| 696 | |
| 697 | /* ------------------------------------------------------------------------ */ |
| 698 | /* Function: ipf_proxy_ioctl */ |
| 699 | /* Returns: int - 0 == success, else error */ |
| 700 | /* Parameters: softc(I) - pointer to soft context main structure */ |
| 701 | /* data(I) - pointer to ioctl data */ |
| 702 | /* cmd(I) - ioctl command */ |
| 703 | /* mode(I) - mode bits for device */ |
| 704 | /* ctx(I) - pointer to context information */ |
| 705 | /* */ |
| 706 | /* ------------------------------------------------------------------------ */ |
| 707 | int |
| 708 | ipf_proxy_ioctl(ipf_main_softc_t *softc, void *data, ioctlcmd_t cmd, int mode, |
| 709 | void *ctx) |
| 710 | { |
| 711 | ap_ctl_t ctl; |
| 712 | void *ptr; |
| 713 | int error; |
| 714 | |
| 715 | mode = mode; /* LINT */ |
| 716 | |
| 717 | switch (cmd) |
| 718 | { |
| 719 | case SIOCPROXY : |
| 720 | error = ipf_inobj(softc, data, NULL, &ctl, IPFOBJ_PROXYCTL); |
| 721 | if (error != 0) { |
| 722 | return error; |
| 723 | } |
| 724 | ptr = NULL; |
| 725 | |
| 726 | if (ctl.apc_dsize > 0) { |
| 727 | KMALLOCS(ptr, void *, ctl.apc_dsize); |
| 728 | if (ptr == NULL) { |
| 729 | IPFERROR(80003); |
| 730 | error = ENOMEM; |
| 731 | } else { |
| 732 | error = copyinptr(softc, ctl.apc_data, ptr, |
| 733 | ctl.apc_dsize); |
| 734 | if (error == 0) |
| 735 | ctl.apc_data = ptr; |
| 736 | } |
| 737 | } else { |
| 738 | ctl.apc_data = NULL; |
| 739 | error = 0; |
| 740 | } |
| 741 | |
| 742 | if (error == 0) |
| 743 | error = ipf_proxy_ctl(softc, softc->ipf_proxy_soft, |
| 744 | &ctl); |
| 745 | |
| 746 | if ((error != 0) && (ptr != NULL)) { |
| 747 | KFREES(ptr, ctl.apc_dsize); |
| 748 | } |
| 749 | break; |
| 750 | |
| 751 | default : |
| 752 | IPFERROR(80004); |
| 753 | error = EINVAL; |
| 754 | } |
| 755 | return error; |
| 756 | } |
| 757 | |
| 758 | |
| 759 | /* ------------------------------------------------------------------------ */ |
| 760 | /* Function: ipf_proxy_match */ |
| 761 | /* Returns: int - 0 == success, else error */ |
| 762 | /* Parameters: fin(I) - pointer to packet information */ |
| 763 | /* nat(I) - pointer to current NAT session */ |
| 764 | /* */ |
| 765 | /* If a proxy has a match function, call that to do extended packet */ |
| 766 | /* matching. Whilst other parts of the NAT code are rather lenient when it */ |
| 767 | /* comes to the quality of the packet that it will transform, the proxy */ |
| 768 | /* matching is not because they need to work with data, not just headers. */ |
| 769 | /* ------------------------------------------------------------------------ */ |
| 770 | int |
| 771 | ipf_proxy_match(fr_info_t *fin, nat_t *nat) |
| 772 | { |
| 773 | ipf_main_softc_t *softc = fin->fin_main_soft; |
| 774 | ipf_proxy_softc_t *softp = softc->ipf_proxy_soft; |
| 775 | aproxy_t *apr; |
| 776 | ipnat_t *ipn; |
| 777 | int result; |
| 778 | |
| 779 | ipn = nat->nat_ptr; |
| 780 | if (softp->ips_proxy_debug & 0x04) |
| 781 | printf("ipf_proxy_match(%lx,%lx) aps %lx ptr %lx\n" , |
| 782 | (u_long)fin, (u_long)nat, (u_long)nat->nat_aps, |
| 783 | (u_long)ipn); |
| 784 | |
| 785 | if ((fin->fin_flx & (FI_SHORT|FI_BAD)) != 0) { |
| 786 | if (softp->ips_proxy_debug & 0x08) |
| 787 | printf("ipf_proxy_match: flx 0x%x (BAD|SHORT)\n" , |
| 788 | fin->fin_flx); |
| 789 | return -1; |
| 790 | } |
| 791 | |
| 792 | apr = ipn->in_apr; |
| 793 | if ((apr == NULL) || (apr->apr_flags & APR_DELETE)) { |
| 794 | if (softp->ips_proxy_debug & 0x08) |
| 795 | printf("ipf_proxy_match:apr %lx apr_flags 0x%x\n" , |
| 796 | (u_long)apr, apr ? apr->apr_flags : 0); |
| 797 | return -1; |
| 798 | } |
| 799 | |
| 800 | if (apr->apr_match != NULL) { |
| 801 | result = (*apr->apr_match)(fin, nat->nat_aps, nat); |
| 802 | if (result != 0) { |
| 803 | if (softp->ips_proxy_debug & 0x08) |
| 804 | printf("ipf_proxy_match: result %d\n" , result); |
| 805 | return -1; |
| 806 | } |
| 807 | } |
| 808 | return 0; |
| 809 | } |
| 810 | |
| 811 | |
| 812 | /* ------------------------------------------------------------------------ */ |
| 813 | /* Function: ipf_proxy_new */ |
| 814 | /* Returns: int - 0 == success, else error */ |
| 815 | /* Parameters: fin(I) - pointer to packet information */ |
| 816 | /* nat(I) - pointer to current NAT session */ |
| 817 | /* */ |
| 818 | /* Allocate a new application proxy structure and fill it in with the */ |
| 819 | /* relevant details. call the init function once complete, prior to */ |
| 820 | /* returning. */ |
| 821 | /* ------------------------------------------------------------------------ */ |
| 822 | int |
| 823 | ipf_proxy_new(fr_info_t *fin, nat_t *nat) |
| 824 | { |
| 825 | ipf_main_softc_t *softc = fin->fin_main_soft; |
| 826 | ipf_proxy_softc_t *softp = softc->ipf_proxy_soft; |
| 827 | register ap_session_t *aps; |
| 828 | aproxy_t *apr; |
| 829 | |
| 830 | if (softp->ips_proxy_debug & 0x04) |
| 831 | printf("ipf_proxy_new(%lx,%lx) \n" , (u_long)fin, (u_long)nat); |
| 832 | |
| 833 | if ((nat->nat_ptr == NULL) || (nat->nat_aps != NULL)) { |
| 834 | if (softp->ips_proxy_debug & 0x08) |
| 835 | printf("ipf_proxy_new: nat_ptr %lx nat_aps %lx\n" , |
| 836 | (u_long)nat->nat_ptr, (u_long)nat->nat_aps); |
| 837 | return -1; |
| 838 | } |
| 839 | |
| 840 | apr = nat->nat_ptr->in_apr; |
| 841 | |
| 842 | if ((apr->apr_flags & APR_DELETE) || |
| 843 | (fin->fin_p != apr->apr_p)) { |
| 844 | if (softp->ips_proxy_debug & 0x08) |
| 845 | printf("ipf_proxy_new: apr_flags 0x%x p %d/%d\n" , |
| 846 | apr->apr_flags, fin->fin_p, apr->apr_p); |
| 847 | return -1; |
| 848 | } |
| 849 | |
| 850 | KMALLOC(aps, ap_session_t *); |
| 851 | if (!aps) { |
| 852 | if (softp->ips_proxy_debug & 0x08) |
| 853 | printf("ipf_proxy_new: malloc failed (%lu)\n" , |
| 854 | (u_long)sizeof(ap_session_t)); |
| 855 | return -1; |
| 856 | } |
| 857 | |
| 858 | bzero((char *)aps, sizeof(*aps)); |
| 859 | aps->aps_data = NULL; |
| 860 | aps->aps_apr = apr; |
| 861 | aps->aps_psiz = 0; |
| 862 | if (apr->apr_new != NULL) |
| 863 | if ((*apr->apr_new)(apr->apr_soft, fin, aps, nat) == -1) { |
| 864 | if ((aps->aps_data != NULL) && (aps->aps_psiz != 0)) { |
| 865 | KFREES(aps->aps_data, aps->aps_psiz); |
| 866 | } |
| 867 | KFREE(aps); |
| 868 | if (softp->ips_proxy_debug & 0x08) |
| 869 | printf("ipf_proxy_new: new(%lx) failed\n" , |
| 870 | (u_long)apr->apr_new); |
| 871 | return -1; |
| 872 | } |
| 873 | aps->aps_nat = nat; |
| 874 | aps->aps_next = softp->ips_sess_list; |
| 875 | softp->ips_sess_list = aps; |
| 876 | nat->nat_aps = aps; |
| 877 | |
| 878 | return 0; |
| 879 | } |
| 880 | |
| 881 | |
| 882 | /* ------------------------------------------------------------------------ */ |
| 883 | /* Function: ipf_proxy_check */ |
| 884 | /* Returns: int - -1 == error, 0 == success */ |
| 885 | /* Parameters: fin(I) - pointer to packet information */ |
| 886 | /* nat(I) - pointer to current NAT session */ |
| 887 | /* */ |
| 888 | /* Check to see if a packet should be passed through an active proxy */ |
| 889 | /* routine if one has been setup for it. We don't need to check the */ |
| 890 | /* checksum here if IPFILTER_CKSUM is defined because if it is, a failed */ |
| 891 | /* check causes FI_BAD to be set. */ |
| 892 | /* ------------------------------------------------------------------------ */ |
| 893 | int |
| 894 | ipf_proxy_check(fr_info_t *fin, nat_t *nat) |
| 895 | { |
| 896 | ipf_main_softc_t *softc = fin->fin_main_soft; |
| 897 | ipf_proxy_softc_t *softp = softc->ipf_proxy_soft; |
| 898 | #if SOLARIS && defined(_KERNEL) && defined(ICK_VALID) |
| 899 | mb_t *m; |
| 900 | #endif |
| 901 | tcphdr_t *tcp = NULL; |
| 902 | udphdr_t *udp = NULL; |
| 903 | ap_session_t *aps; |
| 904 | aproxy_t *apr; |
| 905 | short adjlen; |
| 906 | int dosum; |
| 907 | ip_t *ip; |
| 908 | short rv; |
| 909 | int err; |
| 910 | #if !defined(_KERNEL) || defined(MENTAT) || defined(__sgi) |
| 911 | u_32_t s1, s2, sd; |
| 912 | #endif |
| 913 | |
| 914 | if (fin->fin_flx & FI_BAD) { |
| 915 | if (softp->ips_proxy_debug & 0x08) |
| 916 | printf("ipf_proxy_check: flx 0x%x (BAD)\n" , |
| 917 | fin->fin_flx); |
| 918 | return -1; |
| 919 | } |
| 920 | |
| 921 | #ifndef IPFILTER_CKSUM |
| 922 | if ((fin->fin_out == 0) && (ipf_checkl4sum(fin) == -1)) { |
| 923 | if (softp->ips_proxy_debug & 0x08) |
| 924 | printf("ipf_proxy_check: l4 checksum failure %d\n" , |
| 925 | fin->fin_p); |
| 926 | if (fin->fin_p == IPPROTO_TCP) |
| 927 | softc->ipf_stats[fin->fin_out].fr_tcpbad++; |
| 928 | return -1; |
| 929 | } |
| 930 | #endif |
| 931 | |
| 932 | aps = nat->nat_aps; |
| 933 | if (aps != NULL) { |
| 934 | /* |
| 935 | * If there is data in this packet to be proxied then try and |
| 936 | * get it all into the one buffer, else drop it. |
| 937 | */ |
| 938 | #if defined(MENTAT) || defined(HAVE_M_PULLDOWN) |
| 939 | if ((fin->fin_dlen > 0) && !(fin->fin_flx & FI_COALESCE)) |
| 940 | if (ipf_coalesce(fin) == -1) { |
| 941 | if (softp->ips_proxy_debug & 0x08) |
| 942 | printf("ipf_proxy_check: %s %x\n" , |
| 943 | "coalesce failed" , fin->fin_flx); |
| 944 | return -1; |
| 945 | } |
| 946 | #endif |
| 947 | ip = fin->fin_ip; |
| 948 | if (fin->fin_cksum > FI_CK_SUMOK) |
| 949 | dosum = 0; |
| 950 | else |
| 951 | dosum = 1; |
| 952 | |
| 953 | switch (fin->fin_p) |
| 954 | { |
| 955 | case IPPROTO_TCP : |
| 956 | tcp = (tcphdr_t *)fin->fin_dp; |
| 957 | #if SOLARIS && defined(_KERNEL) && defined(ICK_VALID) |
| 958 | m = fin->fin_qfm; |
| 959 | if (dohwcksum && (m->b_ick_flag == ICK_VALID)) |
| 960 | dosum = 0; |
| 961 | #endif |
| 962 | break; |
| 963 | case IPPROTO_UDP : |
| 964 | udp = (udphdr_t *)fin->fin_dp; |
| 965 | break; |
| 966 | default : |
| 967 | break; |
| 968 | } |
| 969 | |
| 970 | apr = aps->aps_apr; |
| 971 | err = 0; |
| 972 | if (fin->fin_out != 0) { |
| 973 | if (apr->apr_outpkt != NULL) |
| 974 | err = (*apr->apr_outpkt)(apr->apr_soft, fin, |
| 975 | aps, nat); |
| 976 | } else { |
| 977 | if (apr->apr_inpkt != NULL) |
| 978 | err = (*apr->apr_inpkt)(apr->apr_soft, fin, |
| 979 | aps, nat); |
| 980 | } |
| 981 | |
| 982 | rv = APR_EXIT(err); |
| 983 | if (((softp->ips_proxy_debug & 0x08) && (rv != 0)) || |
| 984 | (softp->ips_proxy_debug & 0x04)) |
| 985 | printf("ipf_proxy_check: out %d err %x rv %d\n" , |
| 986 | fin->fin_out, err, rv); |
| 987 | if (rv == 1) |
| 988 | return -1; |
| 989 | |
| 990 | if (rv == 2) { |
| 991 | ipf_proxy_deref(apr); |
| 992 | nat->nat_aps = NULL; |
| 993 | return -1; |
| 994 | } |
| 995 | |
| 996 | /* |
| 997 | * If err != 0 then the data size of the packet has changed |
| 998 | * so we need to recalculate the header checksums for the |
| 999 | * packet. |
| 1000 | */ |
| 1001 | adjlen = APR_INC(err); |
| 1002 | #if !defined(_KERNEL) || defined(MENTAT) || defined(__sgi) |
| 1003 | s1 = LONG_SUM(fin->fin_plen - adjlen); |
| 1004 | s2 = LONG_SUM(fin->fin_plen); |
| 1005 | CALC_SUMD(s1, s2, sd); |
| 1006 | if ((err != 0) && (fin->fin_cksum < FI_CK_L4PART) && |
| 1007 | fin->fin_v == 4) |
| 1008 | ipf_fix_outcksum(0, &ip->ip_sum, sd, 0); |
| 1009 | #endif |
| 1010 | if (fin->fin_flx & FI_DOCKSUM) |
| 1011 | dosum = 1; |
| 1012 | |
| 1013 | #ifdef INET |
| 1014 | /* |
| 1015 | * For TCP packets, we may need to adjust the sequence and |
| 1016 | * acknowledgement numbers to reflect changes in size of the |
| 1017 | * data stream. |
| 1018 | * |
| 1019 | * For both TCP and UDP, recalculate the layer 4 checksum, |
| 1020 | * regardless, as we can't tell (here) if data has been |
| 1021 | * changed or not. |
| 1022 | */ |
| 1023 | if (tcp != NULL) { |
| 1024 | err = ipf_proxy_fixseqack(fin, ip, aps, adjlen); |
| 1025 | if (fin->fin_cksum == FI_CK_L4PART) { |
| 1026 | u_short sum = ntohs(tcp->th_sum); |
| 1027 | sum += adjlen; |
| 1028 | tcp->th_sum = htons(sum); |
| 1029 | } else if (fin->fin_cksum < FI_CK_L4PART) { |
| 1030 | tcp->th_sum = fr_cksum(fin, ip, |
| 1031 | IPPROTO_TCP, tcp); |
| 1032 | } |
| 1033 | } else if ((udp != NULL) && (udp->uh_sum != 0)) { |
| 1034 | if (fin->fin_cksum == FI_CK_L4PART) { |
| 1035 | u_short sum = ntohs(udp->uh_sum); |
| 1036 | sum += adjlen; |
| 1037 | udp->uh_sum = htons(sum); |
| 1038 | } else if (dosum) { |
| 1039 | udp->uh_sum = fr_cksum(fin, ip, |
| 1040 | IPPROTO_UDP, udp); |
| 1041 | } |
| 1042 | } |
| 1043 | #endif |
| 1044 | aps->aps_bytes += fin->fin_plen; |
| 1045 | aps->aps_pkts++; |
| 1046 | return 1; |
| 1047 | } |
| 1048 | return 0; |
| 1049 | } |
| 1050 | |
| 1051 | |
| 1052 | /* ------------------------------------------------------------------------ */ |
| 1053 | /* Function: ipf_proxy_lookup */ |
| 1054 | /* Returns: int - -1 == error, 0 == success */ |
| 1055 | /* Parameters: arg(I) - pointer to proxy context information */ |
| 1056 | /* pr(I) - protocol number for proxy */ |
| 1057 | /* name(I) - proxy name */ |
| 1058 | /* */ |
| 1059 | /* Search for an proxy by the protocol it is being used with and its name. */ |
| 1060 | /* ------------------------------------------------------------------------ */ |
| 1061 | aproxy_t * |
| 1062 | ipf_proxy_lookup(void *arg, u_int pr, char *name) |
| 1063 | { |
| 1064 | ipf_proxy_softc_t *softp = arg; |
| 1065 | aproxy_t *ap; |
| 1066 | |
| 1067 | if (softp->ips_proxy_debug & 0x04) |
| 1068 | printf("ipf_proxy_lookup(%d,%s)\n" , pr, name); |
| 1069 | |
| 1070 | for (ap = softp->ips_proxies; ap != NULL; ap = ap->apr_next) |
| 1071 | if ((ap->apr_p == pr) && |
| 1072 | !strncmp(name, ap->apr_label, sizeof(ap->apr_label))) { |
| 1073 | ap->apr_ref++; |
| 1074 | return ap; |
| 1075 | } |
| 1076 | |
| 1077 | if (softp->ips_proxy_debug & 0x08) |
| 1078 | printf("ipf_proxy_lookup: failed for %d/%s\n" , pr, name); |
| 1079 | return NULL; |
| 1080 | } |
| 1081 | |
| 1082 | |
| 1083 | /* ------------------------------------------------------------------------ */ |
| 1084 | /* Function: ipf_proxy_deref */ |
| 1085 | /* Returns: Nil */ |
| 1086 | /* Parameters: ap(I) - pointer to proxy structure */ |
| 1087 | /* */ |
| 1088 | /* Drop the reference counter associated with the proxy. */ |
| 1089 | /* ------------------------------------------------------------------------ */ |
| 1090 | void |
| 1091 | ipf_proxy_deref(aproxy_t *ap) |
| 1092 | { |
| 1093 | ap->apr_ref--; |
| 1094 | } |
| 1095 | |
| 1096 | |
| 1097 | /* ------------------------------------------------------------------------ */ |
| 1098 | /* Function: ipf_proxy_free */ |
| 1099 | /* Returns: Nil */ |
| 1100 | /* Parameters: softc(I) - pointer to soft context main structure */ |
| 1101 | /* aps(I) - pointer to current proxy session */ |
| 1102 | /* Locks Held: ipf_nat_new, ipf_nat(W) */ |
| 1103 | /* */ |
| 1104 | /* Free up proxy session information allocated to be used with a NAT */ |
| 1105 | /* session. */ |
| 1106 | /* ------------------------------------------------------------------------ */ |
| 1107 | void |
| 1108 | ipf_proxy_free(ipf_main_softc_t *softc, ap_session_t *aps) |
| 1109 | { |
| 1110 | ipf_proxy_softc_t *softp = softc->ipf_proxy_soft; |
| 1111 | ap_session_t *a, **ap; |
| 1112 | aproxy_t *apr; |
| 1113 | |
| 1114 | if (!aps) |
| 1115 | return; |
| 1116 | |
| 1117 | for (ap = &softp->ips_sess_list; ((a = *ap) != NULL); ap = &a->aps_next) |
| 1118 | if (a == aps) { |
| 1119 | *ap = a->aps_next; |
| 1120 | break; |
| 1121 | } |
| 1122 | |
| 1123 | apr = aps->aps_apr; |
| 1124 | if ((apr != NULL) && (apr->apr_del != NULL)) |
| 1125 | (*apr->apr_del)(softc, aps); |
| 1126 | |
| 1127 | if ((aps->aps_data != NULL) && (aps->aps_psiz != 0)) |
| 1128 | KFREES(aps->aps_data, aps->aps_psiz); |
| 1129 | KFREE(aps); |
| 1130 | } |
| 1131 | |
| 1132 | |
| 1133 | /* ------------------------------------------------------------------------ */ |
| 1134 | /* Function: ipf_proxy_fixseqack */ |
| 1135 | /* Returns: int - 2 if TCP ack/seq is changed, else 0 */ |
| 1136 | /* Parameters: fin(I) - pointer to packet information */ |
| 1137 | /* ip(I) - pointer to IP header */ |
| 1138 | /* nat(I) - pointer to current NAT session */ |
| 1139 | /* inc(I) - delta to apply to TCP sequence numbering */ |
| 1140 | /* */ |
| 1141 | /* Adjust the TCP sequence/acknowledge numbers in the TCP header based on */ |
| 1142 | /* whether or not the new header is past the point at which an adjustment */ |
| 1143 | /* occurred. This might happen because of (say) an FTP string being changed */ |
| 1144 | /* and the new string being a different length to the old. */ |
| 1145 | /* ------------------------------------------------------------------------ */ |
| 1146 | static int |
| 1147 | ipf_proxy_fixseqack(fr_info_t *fin, ip_t *ip, ap_session_t *aps, int inc) |
| 1148 | { |
| 1149 | ipf_main_softc_t *softc = fin->fin_main_soft; |
| 1150 | ipf_proxy_softc_t *softp = softc->ipf_proxy_soft; |
| 1151 | int sel, ch = 0, out, nlen; |
| 1152 | u_32_t seq1, seq2; |
| 1153 | tcphdr_t *tcp; |
| 1154 | short inc2; |
| 1155 | |
| 1156 | tcp = (tcphdr_t *)fin->fin_dp; |
| 1157 | out = fin->fin_out; |
| 1158 | /* |
| 1159 | * ip_len has already been adjusted by 'inc'. |
| 1160 | */ |
| 1161 | nlen = fin->fin_dlen; |
| 1162 | nlen -= (TCP_OFF(tcp) << 2); |
| 1163 | |
| 1164 | inc2 = inc; |
| 1165 | inc = (int)inc2; |
| 1166 | |
| 1167 | if (out != 0) { |
| 1168 | seq1 = (u_32_t)ntohl(tcp->th_seq); |
| 1169 | sel = aps->aps_sel[out]; |
| 1170 | |
| 1171 | /* switch to other set ? */ |
| 1172 | if ((aps->aps_seqmin[!sel] > aps->aps_seqmin[sel]) && |
| 1173 | (seq1 > aps->aps_seqmin[!sel])) { |
| 1174 | if (softp->ips_proxy_debug & 0x10) |
| 1175 | printf("proxy out switch set seq %d -> %d %x > %x\n" , |
| 1176 | sel, !sel, seq1, |
| 1177 | aps->aps_seqmin[!sel]); |
| 1178 | sel = aps->aps_sel[out] = !sel; |
| 1179 | } |
| 1180 | |
| 1181 | if (aps->aps_seqoff[sel]) { |
| 1182 | seq2 = aps->aps_seqmin[sel] - aps->aps_seqoff[sel]; |
| 1183 | if (seq1 > seq2) { |
| 1184 | seq2 = aps->aps_seqoff[sel]; |
| 1185 | seq1 += seq2; |
| 1186 | tcp->th_seq = htonl(seq1); |
| 1187 | ch = 1; |
| 1188 | } |
| 1189 | } |
| 1190 | |
| 1191 | if (inc && (seq1 > aps->aps_seqmin[!sel])) { |
| 1192 | aps->aps_seqmin[sel] = seq1 + nlen - 1; |
| 1193 | aps->aps_seqoff[sel] = aps->aps_seqoff[sel] + inc; |
| 1194 | if (softp->ips_proxy_debug & 0x10) |
| 1195 | printf("proxy seq set %d at %x to %d + %d\n" , |
| 1196 | sel, aps->aps_seqmin[sel], |
| 1197 | aps->aps_seqoff[sel], inc); |
| 1198 | } |
| 1199 | |
| 1200 | /***/ |
| 1201 | |
| 1202 | seq1 = ntohl(tcp->th_ack); |
| 1203 | sel = aps->aps_sel[1 - out]; |
| 1204 | |
| 1205 | /* switch to other set ? */ |
| 1206 | if ((aps->aps_ackmin[!sel] > aps->aps_ackmin[sel]) && |
| 1207 | (seq1 > aps->aps_ackmin[!sel])) { |
| 1208 | if (softp->ips_proxy_debug & 0x10) |
| 1209 | printf("proxy out switch set ack %d -> %d %x > %x\n" , |
| 1210 | sel, !sel, seq1, |
| 1211 | aps->aps_ackmin[!sel]); |
| 1212 | sel = aps->aps_sel[1 - out] = !sel; |
| 1213 | } |
| 1214 | |
| 1215 | if (aps->aps_ackoff[sel] && (seq1 > aps->aps_ackmin[sel])) { |
| 1216 | seq2 = aps->aps_ackoff[sel]; |
| 1217 | tcp->th_ack = htonl(seq1 - seq2); |
| 1218 | ch = 1; |
| 1219 | } |
| 1220 | } else { |
| 1221 | seq1 = ntohl(tcp->th_seq); |
| 1222 | sel = aps->aps_sel[out]; |
| 1223 | |
| 1224 | /* switch to other set ? */ |
| 1225 | if ((aps->aps_ackmin[!sel] > aps->aps_ackmin[sel]) && |
| 1226 | (seq1 > aps->aps_ackmin[!sel])) { |
| 1227 | if (softp->ips_proxy_debug & 0x10) |
| 1228 | printf("proxy in switch set ack %d -> %d %x > %x\n" , |
| 1229 | sel, !sel, seq1, aps->aps_ackmin[!sel]); |
| 1230 | sel = aps->aps_sel[out] = !sel; |
| 1231 | } |
| 1232 | |
| 1233 | if (aps->aps_ackoff[sel]) { |
| 1234 | seq2 = aps->aps_ackmin[sel] - aps->aps_ackoff[sel]; |
| 1235 | if (seq1 > seq2) { |
| 1236 | seq2 = aps->aps_ackoff[sel]; |
| 1237 | seq1 += seq2; |
| 1238 | tcp->th_seq = htonl(seq1); |
| 1239 | ch = 1; |
| 1240 | } |
| 1241 | } |
| 1242 | |
| 1243 | if (inc && (seq1 > aps->aps_ackmin[!sel])) { |
| 1244 | aps->aps_ackmin[!sel] = seq1 + nlen - 1; |
| 1245 | aps->aps_ackoff[!sel] = aps->aps_ackoff[sel] + inc; |
| 1246 | |
| 1247 | if (softp->ips_proxy_debug & 0x10) |
| 1248 | printf("proxy ack set %d at %x to %d + %d\n" , |
| 1249 | !sel, aps->aps_seqmin[!sel], |
| 1250 | aps->aps_seqoff[sel], inc); |
| 1251 | } |
| 1252 | |
| 1253 | /***/ |
| 1254 | |
| 1255 | seq1 = ntohl(tcp->th_ack); |
| 1256 | sel = aps->aps_sel[1 - out]; |
| 1257 | |
| 1258 | /* switch to other set ? */ |
| 1259 | if ((aps->aps_seqmin[!sel] > aps->aps_seqmin[sel]) && |
| 1260 | (seq1 > aps->aps_seqmin[!sel])) { |
| 1261 | if (softp->ips_proxy_debug & 0x10) |
| 1262 | printf("proxy in switch set seq %d -> %d %x > %x\n" , |
| 1263 | sel, !sel, seq1, aps->aps_seqmin[!sel]); |
| 1264 | sel = aps->aps_sel[1 - out] = !sel; |
| 1265 | } |
| 1266 | |
| 1267 | if (aps->aps_seqoff[sel] != 0) { |
| 1268 | if (softp->ips_proxy_debug & 0x10) |
| 1269 | printf("sel %d seqoff %d seq1 %x seqmin %x\n" , |
| 1270 | sel, aps->aps_seqoff[sel], seq1, |
| 1271 | aps->aps_seqmin[sel]); |
| 1272 | if (seq1 > aps->aps_seqmin[sel]) { |
| 1273 | seq2 = aps->aps_seqoff[sel]; |
| 1274 | tcp->th_ack = htonl(seq1 - seq2); |
| 1275 | ch = 1; |
| 1276 | } |
| 1277 | } |
| 1278 | } |
| 1279 | |
| 1280 | if (softp->ips_proxy_debug & 0x10) |
| 1281 | printf("ipf_proxy_fixseqack: seq %u ack %u\n" , |
| 1282 | (u_32_t)ntohl(tcp->th_seq), (u_32_t)ntohl(tcp->th_ack)); |
| 1283 | return ch ? 2 : 0; |
| 1284 | } |
| 1285 | |
| 1286 | |
| 1287 | /* ------------------------------------------------------------------------ */ |
| 1288 | /* Function: ipf_proxy_rule_rev */ |
| 1289 | /* Returns: ipnat_t * - NULL = failure, else pointer to new rule */ |
| 1290 | /* Parameters: nat(I) - pointer to NAT session to create rule from */ |
| 1291 | /* */ |
| 1292 | /* This function creates a NAT rule that is based upon the reverse packet */ |
| 1293 | /* flow associated with this NAT session. Thus if this NAT session was */ |
| 1294 | /* created with a map rule then this function will create a rdr rule. */ |
| 1295 | /* Only address fields and network interfaces are assigned in this function */ |
| 1296 | /* and the address fields are formed such that an exact is required. If the */ |
| 1297 | /* original rule had a netmask, that is not replicated here not is it */ |
| 1298 | /* desired. The ultimate goal here is to create a NAT rule to support a NAT */ |
| 1299 | /* session being created that does not have a user configured rule. The */ |
| 1300 | /* classic example is supporting the FTP proxy, where a data channel needs */ |
| 1301 | /* to be setup, based on the addresses used for the control connection. In */ |
| 1302 | /* that case, this function is used to handle creating NAT rules to support */ |
| 1303 | /* data connections with the PORT and EPRT commands. */ |
| 1304 | /* ------------------------------------------------------------------------ */ |
| 1305 | ipnat_t * |
| 1306 | ipf_proxy_rule_rev(nat_t *nat) |
| 1307 | { |
| 1308 | ipnat_t *old; |
| 1309 | ipnat_t *ipn; |
| 1310 | int size; |
| 1311 | |
| 1312 | old = nat->nat_ptr; |
| 1313 | size = old->in_size; |
| 1314 | |
| 1315 | KMALLOCS(ipn, ipnat_t *, size); |
| 1316 | if (ipn == NULL) |
| 1317 | return NULL; |
| 1318 | |
| 1319 | bzero((char *)ipn, size); |
| 1320 | |
| 1321 | ipn->in_use = 1; |
| 1322 | ipn->in_hits = 1; |
| 1323 | ipn->in_ippip = 1; |
| 1324 | ipn->in_apr = NULL; |
| 1325 | ipn->in_size = size; |
| 1326 | ipn->in_pr[0] = old->in_pr[1]; |
| 1327 | ipn->in_pr[1] = old->in_pr[0]; |
| 1328 | ipn->in_v[0] = old->in_v[1]; |
| 1329 | ipn->in_v[1] = old->in_v[0]; |
| 1330 | ipn->in_ifps[0] = old->in_ifps[1]; |
| 1331 | ipn->in_ifps[1] = old->in_ifps[0]; |
| 1332 | ipn->in_flags = (old->in_flags | IPN_PROXYRULE); |
| 1333 | |
| 1334 | ipn->in_nsrcip6 = nat->nat_odst6; |
| 1335 | ipn->in_osrcip6 = nat->nat_ndst6; |
| 1336 | |
| 1337 | if ((old->in_redir & NAT_REDIRECT) != 0) { |
| 1338 | ipn->in_redir = NAT_MAP; |
| 1339 | if (ipn->in_v[0] == 4) { |
| 1340 | ipn->in_snip = ntohl(nat->nat_odstaddr); |
| 1341 | ipn->in_dnip = ntohl(nat->nat_nsrcaddr); |
| 1342 | } else { |
| 1343 | #ifdef USE_INET6 |
| 1344 | ipn->in_snip6 = nat->nat_odst6; |
| 1345 | ipn->in_dnip6 = nat->nat_nsrc6; |
| 1346 | #endif |
| 1347 | } |
| 1348 | ipn->in_ndstip6 = nat->nat_nsrc6; |
| 1349 | ipn->in_odstip6 = nat->nat_osrc6; |
| 1350 | } else { |
| 1351 | ipn->in_redir = NAT_REDIRECT; |
| 1352 | if (ipn->in_v[0] == 4) { |
| 1353 | ipn->in_snip = ntohl(nat->nat_odstaddr); |
| 1354 | ipn->in_dnip = ntohl(nat->nat_osrcaddr); |
| 1355 | } else { |
| 1356 | #ifdef USE_INET6 |
| 1357 | ipn->in_snip6 = nat->nat_odst6; |
| 1358 | ipn->in_dnip6 = nat->nat_osrc6; |
| 1359 | #endif |
| 1360 | } |
| 1361 | ipn->in_ndstip6 = nat->nat_osrc6; |
| 1362 | ipn->in_odstip6 = nat->nat_nsrc6; |
| 1363 | } |
| 1364 | |
| 1365 | IP6_SETONES(&ipn->in_osrcmsk6); |
| 1366 | IP6_SETONES(&ipn->in_nsrcmsk6); |
| 1367 | IP6_SETONES(&ipn->in_odstmsk6); |
| 1368 | IP6_SETONES(&ipn->in_ndstmsk6); |
| 1369 | |
| 1370 | ipn->in_namelen = old->in_namelen; |
| 1371 | ipn->in_ifnames[0] = old->in_ifnames[1]; |
| 1372 | ipn->in_ifnames[1] = old->in_ifnames[0]; |
| 1373 | bcopy(old->in_names, ipn->in_names, ipn->in_namelen); |
| 1374 | MUTEX_INIT(&ipn->in_lock, "ipnat rev rule lock" ); |
| 1375 | |
| 1376 | return ipn; |
| 1377 | } |
| 1378 | |
| 1379 | |
| 1380 | /* ------------------------------------------------------------------------ */ |
| 1381 | /* Function: ipf_proxy_rule_fwd */ |
| 1382 | /* Returns: ipnat_t * - NULL = failure, else pointer to new rule */ |
| 1383 | /* Parameters: nat(I) - pointer to NAT session to create rule from */ |
| 1384 | /* */ |
| 1385 | /* The purpose and rationale of this function is much the same as the above */ |
| 1386 | /* function, ipf_proxy_rule_rev, except that a rule is created that matches */ |
| 1387 | /* the same direction as that of the existing NAT session. Thus if this NAT */ |
| 1388 | /* session was created with a map rule then this function will also create */ |
| 1389 | /* a data structure to represent a map rule. Whereas ipf_proxy_rule_rev is */ |
| 1390 | /* used to support PORT/EPRT, this function supports PASV/EPSV. */ |
| 1391 | /* ------------------------------------------------------------------------ */ |
| 1392 | ipnat_t * |
| 1393 | ipf_proxy_rule_fwd(nat_t *nat) |
| 1394 | { |
| 1395 | ipnat_t *old; |
| 1396 | ipnat_t *ipn; |
| 1397 | int size; |
| 1398 | |
| 1399 | old = nat->nat_ptr; |
| 1400 | size = old->in_size; |
| 1401 | |
| 1402 | KMALLOCS(ipn, ipnat_t *, size); |
| 1403 | if (ipn == NULL) |
| 1404 | return NULL; |
| 1405 | |
| 1406 | bzero((char *)ipn, size); |
| 1407 | |
| 1408 | ipn->in_use = 1; |
| 1409 | ipn->in_hits = 1; |
| 1410 | ipn->in_ippip = 1; |
| 1411 | ipn->in_apr = NULL; |
| 1412 | ipn->in_size = size; |
| 1413 | ipn->in_pr[0] = old->in_pr[0]; |
| 1414 | ipn->in_pr[1] = old->in_pr[1]; |
| 1415 | ipn->in_v[0] = old->in_v[0]; |
| 1416 | ipn->in_v[1] = old->in_v[1]; |
| 1417 | ipn->in_ifps[0] = nat->nat_ifps[0]; |
| 1418 | ipn->in_ifps[1] = nat->nat_ifps[1]; |
| 1419 | ipn->in_flags = (old->in_flags | IPN_PROXYRULE); |
| 1420 | |
| 1421 | ipn->in_nsrcip6 = nat->nat_nsrc6; |
| 1422 | ipn->in_osrcip6 = nat->nat_osrc6; |
| 1423 | ipn->in_ndstip6 = nat->nat_ndst6; |
| 1424 | ipn->in_odstip6 = nat->nat_odst6; |
| 1425 | ipn->in_redir = old->in_redir; |
| 1426 | |
| 1427 | if (ipn->in_v[0] == 4) { |
| 1428 | ipn->in_snip = ntohl(nat->nat_nsrcaddr); |
| 1429 | ipn->in_dnip = ntohl(nat->nat_ndstaddr); |
| 1430 | } else { |
| 1431 | #ifdef USE_INET6 |
| 1432 | ipn->in_snip6 = nat->nat_nsrc6; |
| 1433 | ipn->in_dnip6 = nat->nat_ndst6; |
| 1434 | #endif |
| 1435 | } |
| 1436 | |
| 1437 | IP6_SETONES(&ipn->in_osrcmsk6); |
| 1438 | IP6_SETONES(&ipn->in_nsrcmsk6); |
| 1439 | IP6_SETONES(&ipn->in_odstmsk6); |
| 1440 | IP6_SETONES(&ipn->in_ndstmsk6); |
| 1441 | |
| 1442 | ipn->in_namelen = old->in_namelen; |
| 1443 | ipn->in_ifnames[0] = old->in_ifnames[0]; |
| 1444 | ipn->in_ifnames[1] = old->in_ifnames[1]; |
| 1445 | bcopy(old->in_names, ipn->in_names, ipn->in_namelen); |
| 1446 | MUTEX_INIT(&ipn->in_lock, "ipnat fwd rule lock" ); |
| 1447 | |
| 1448 | return ipn; |
| 1449 | } |
| 1450 | |