1 #include <stdio.h> 2 #include <netdb.h> 3 #include <string.h> 4 #include <stdlib.h> 5 #include <xtables.h> 6 #include <limits.h> /* INT_MAX in ip_tables.h/ip6_tables.h */ 7 #include <linux/netfilter_ipv4/ip_tables.h> 8 #include <linux/netfilter_ipv6/ip6_tables.h> 9 #include <linux/netfilter/xt_multiport.h> 10 11 enum { 12 O_SOURCE_PORTS = 0, 13 O_DEST_PORTS, 14 O_SD_PORTS, 15 F_SOURCE_PORTS = 1 << O_SOURCE_PORTS, 16 F_DEST_PORTS = 1 << O_DEST_PORTS, 17 F_SD_PORTS = 1 << O_SD_PORTS, 18 F_ANY = F_SOURCE_PORTS | F_DEST_PORTS | F_SD_PORTS, 19 }; 20 21 /* Function which prints out usage message. */ 22 static void multiport_help(void) 23 { 24 printf( 25 "multiport match options:\n" 26 " --source-ports port[,port,port...]\n" 27 " --sports ...\n" 28 " match source port(s)\n" 29 " --destination-ports port[,port,port...]\n" 30 " --dports ...\n" 31 " match destination port(s)\n" 32 " --ports port[,port,port]\n" 33 " match both source and destination port(s)\n" 34 " NOTE: this kernel does not support port ranges in multiport.\n"); 35 } 36 37 static void multiport_help_v1(void) 38 { 39 printf( 40 "multiport match options:\n" 41 "[!] --source-ports port[,port:port,port...]\n" 42 " --sports ...\n" 43 " match source port(s)\n" 44 "[!] --destination-ports port[,port:port,port...]\n" 45 " --dports ...\n" 46 " match destination port(s)\n" 47 "[!] --ports port[,port:port,port]\n" 48 " match both source and destination port(s)\n"); 49 } 50 51 static const struct xt_option_entry multiport_opts[] = { 52 {.name = "source-ports", .id = O_SOURCE_PORTS, .type = XTTYPE_STRING, 53 .excl = F_ANY, .flags = XTOPT_INVERT}, 54 {.name = "sports", .id = O_SOURCE_PORTS, .type = XTTYPE_STRING, 55 .excl = F_ANY, .flags = XTOPT_INVERT}, 56 {.name = "destination-ports", .id = O_DEST_PORTS, 57 .type = XTTYPE_STRING, .excl = F_ANY, .flags = XTOPT_INVERT}, 58 {.name = "dports", .id = O_DEST_PORTS, .type = XTTYPE_STRING, 59 .excl = F_ANY, .flags = XTOPT_INVERT}, 60 {.name = "ports", .id = O_SD_PORTS, .type = XTTYPE_STRING, 61 .excl = F_ANY, .flags = XTOPT_INVERT}, 62 XTOPT_TABLEEND, 63 }; 64 65 static const char * 66 proto_to_name(uint8_t proto) 67 { 68 switch (proto) { 69 case IPPROTO_TCP: 70 return "tcp"; 71 case IPPROTO_UDP: 72 return "udp"; 73 case IPPROTO_UDPLITE: 74 return "udplite"; 75 case IPPROTO_SCTP: 76 return "sctp"; 77 case IPPROTO_DCCP: 78 return "dccp"; 79 default: 80 return NULL; 81 } 82 } 83 84 static unsigned int 85 parse_multi_ports(const char *portstring, uint16_t *ports, const char *proto) 86 { 87 char *buffer, *cp, *next; 88 unsigned int i; 89 90 buffer = strdup(portstring); 91 if (!buffer) xtables_error(OTHER_PROBLEM, "strdup failed"); 92 93 for (cp=buffer, i=0; cp && i<XT_MULTI_PORTS; cp=next,i++) 94 { 95 next=strchr(cp, ','); 96 if (next) *next++='\0'; 97 ports[i] = xtables_parse_port(cp, proto); 98 } 99 if (cp) xtables_error(PARAMETER_PROBLEM, "too many ports specified"); 100 free(buffer); 101 return i; 102 } 103 104 static void 105 parse_multi_ports_v1(const char *portstring, 106 struct xt_multiport_v1 *multiinfo, 107 const char *proto) 108 { 109 char *buffer, *cp, *next, *range; 110 unsigned int i; 111 uint16_t m; 112 113 buffer = strdup(portstring); 114 if (!buffer) xtables_error(OTHER_PROBLEM, "strdup failed"); 115 116 for (i=0; i<XT_MULTI_PORTS; i++) 117 multiinfo->pflags[i] = 0; 118 119 for (cp=buffer, i=0; cp && i<XT_MULTI_PORTS; cp=next, i++) { 120 next=strchr(cp, ','); 121 if (next) *next++='\0'; 122 range = strchr(cp, ':'); 123 if (range) { 124 if (i == XT_MULTI_PORTS-1) 125 xtables_error(PARAMETER_PROBLEM, 126 "too many ports specified"); 127 *range++ = '\0'; 128 } 129 multiinfo->ports[i] = xtables_parse_port(cp, proto); 130 if (range) { 131 multiinfo->pflags[i] = 1; 132 multiinfo->ports[++i] = xtables_parse_port(range, proto); 133 if (multiinfo->ports[i-1] >= multiinfo->ports[i]) 134 xtables_error(PARAMETER_PROBLEM, 135 "invalid portrange specified"); 136 m <<= 1; 137 } 138 } 139 multiinfo->count = i; 140 if (cp) xtables_error(PARAMETER_PROBLEM, "too many ports specified"); 141 free(buffer); 142 } 143 144 static const char * 145 check_proto(uint16_t pnum, uint8_t invflags) 146 { 147 const char *proto; 148 149 if (invflags & XT_INV_PROTO) 150 xtables_error(PARAMETER_PROBLEM, 151 "multiport only works with TCP, UDP, UDPLITE, SCTP and DCCP"); 152 153 if ((proto = proto_to_name(pnum)) != NULL) 154 return proto; 155 else if (!pnum) 156 xtables_error(PARAMETER_PROBLEM, 157 "multiport needs `-p tcp', `-p udp', `-p udplite', " 158 "`-p sctp' or `-p dccp'"); 159 else 160 xtables_error(PARAMETER_PROBLEM, 161 "multiport only works with TCP, UDP, UDPLITE, SCTP and DCCP"); 162 } 163 164 static void __multiport_parse(struct xt_option_call *cb, uint16_t pnum, 165 uint8_t invflags) 166 { 167 const char *proto; 168 struct xt_multiport *multiinfo = cb->data; 169 170 xtables_option_parse(cb); 171 switch (cb->entry->id) { 172 case O_SOURCE_PORTS: 173 proto = check_proto(pnum, invflags); 174 multiinfo->count = parse_multi_ports(cb->arg, 175 multiinfo->ports, proto); 176 multiinfo->flags = XT_MULTIPORT_SOURCE; 177 break; 178 case O_DEST_PORTS: 179 proto = check_proto(pnum, invflags); 180 multiinfo->count = parse_multi_ports(cb->arg, 181 multiinfo->ports, proto); 182 multiinfo->flags = XT_MULTIPORT_DESTINATION; 183 break; 184 case O_SD_PORTS: 185 proto = check_proto(pnum, invflags); 186 multiinfo->count = parse_multi_ports(cb->arg, 187 multiinfo->ports, proto); 188 multiinfo->flags = XT_MULTIPORT_EITHER; 189 break; 190 } 191 if (cb->invert) 192 xtables_error(PARAMETER_PROBLEM, 193 "multiport.0 does not support invert"); 194 } 195 196 static void multiport_parse(struct xt_option_call *cb) 197 { 198 const struct ipt_entry *entry = cb->xt_entry; 199 return __multiport_parse(cb, 200 entry->ip.proto, entry->ip.invflags); 201 } 202 203 static void multiport_parse6(struct xt_option_call *cb) 204 { 205 const struct ip6t_entry *entry = cb->xt_entry; 206 return __multiport_parse(cb, 207 entry->ipv6.proto, entry->ipv6.invflags); 208 } 209 210 static void __multiport_parse_v1(struct xt_option_call *cb, uint16_t pnum, 211 uint8_t invflags) 212 { 213 const char *proto; 214 struct xt_multiport_v1 *multiinfo = cb->data; 215 216 xtables_option_parse(cb); 217 switch (cb->entry->id) { 218 case O_SOURCE_PORTS: 219 proto = check_proto(pnum, invflags); 220 parse_multi_ports_v1(cb->arg, multiinfo, proto); 221 multiinfo->flags = XT_MULTIPORT_SOURCE; 222 break; 223 case O_DEST_PORTS: 224 proto = check_proto(pnum, invflags); 225 parse_multi_ports_v1(cb->arg, multiinfo, proto); 226 multiinfo->flags = XT_MULTIPORT_DESTINATION; 227 break; 228 case O_SD_PORTS: 229 proto = check_proto(pnum, invflags); 230 parse_multi_ports_v1(cb->arg, multiinfo, proto); 231 multiinfo->flags = XT_MULTIPORT_EITHER; 232 break; 233 } 234 if (cb->invert) 235 multiinfo->invert = 1; 236 } 237 238 static void multiport_parse_v1(struct xt_option_call *cb) 239 { 240 const struct ipt_entry *entry = cb->xt_entry; 241 return __multiport_parse_v1(cb, 242 entry->ip.proto, entry->ip.invflags); 243 } 244 245 static void multiport_parse6_v1(struct xt_option_call *cb) 246 { 247 const struct ip6t_entry *entry = cb->xt_entry; 248 return __multiport_parse_v1(cb, 249 entry->ipv6.proto, entry->ipv6.invflags); 250 } 251 252 static void multiport_check(struct xt_fcheck_call *cb) 253 { 254 if (cb->xflags == 0) 255 xtables_error(PARAMETER_PROBLEM, "multiport expection an option"); 256 } 257 258 static const char * 259 port_to_service(int port, uint8_t proto) 260 { 261 const struct servent *service; 262 263 if ((service = getservbyport(htons(port), proto_to_name(proto)))) 264 return service->s_name; 265 266 return NULL; 267 } 268 269 static void 270 print_port(uint16_t port, uint8_t protocol, int numeric) 271 { 272 const char *service; 273 274 if (numeric || (service = port_to_service(port, protocol)) == NULL) 275 printf("%u", port); 276 else 277 printf("%s", service); 278 } 279 280 static void 281 __multiport_print(const struct xt_entry_match *match, int numeric, 282 uint16_t proto) 283 { 284 const struct xt_multiport *multiinfo 285 = (const struct xt_multiport *)match->data; 286 unsigned int i; 287 288 printf(" multiport "); 289 290 switch (multiinfo->flags) { 291 case XT_MULTIPORT_SOURCE: 292 printf("sports "); 293 break; 294 295 case XT_MULTIPORT_DESTINATION: 296 printf("dports "); 297 break; 298 299 case XT_MULTIPORT_EITHER: 300 printf("ports "); 301 break; 302 303 default: 304 printf("ERROR "); 305 break; 306 } 307 308 for (i=0; i < multiinfo->count; i++) { 309 printf("%s", i ? "," : ""); 310 print_port(multiinfo->ports[i], proto, numeric); 311 } 312 } 313 314 static void multiport_print(const void *ip_void, 315 const struct xt_entry_match *match, int numeric) 316 { 317 const struct ipt_ip *ip = ip_void; 318 __multiport_print(match, numeric, ip->proto); 319 } 320 321 static void multiport_print6(const void *ip_void, 322 const struct xt_entry_match *match, int numeric) 323 { 324 const struct ip6t_ip6 *ip = ip_void; 325 __multiport_print(match, numeric, ip->proto); 326 } 327 328 static void __multiport_print_v1(const struct xt_entry_match *match, 329 int numeric, uint16_t proto) 330 { 331 const struct xt_multiport_v1 *multiinfo 332 = (const struct xt_multiport_v1 *)match->data; 333 unsigned int i; 334 335 printf(" multiport "); 336 337 switch (multiinfo->flags) { 338 case XT_MULTIPORT_SOURCE: 339 printf("sports "); 340 break; 341 342 case XT_MULTIPORT_DESTINATION: 343 printf("dports "); 344 break; 345 346 case XT_MULTIPORT_EITHER: 347 printf("ports "); 348 break; 349 350 default: 351 printf("ERROR "); 352 break; 353 } 354 355 if (multiinfo->invert) 356 printf(" !"); 357 358 for (i=0; i < multiinfo->count; i++) { 359 printf("%s", i ? "," : ""); 360 print_port(multiinfo->ports[i], proto, numeric); 361 if (multiinfo->pflags[i]) { 362 printf(":"); 363 print_port(multiinfo->ports[++i], proto, numeric); 364 } 365 } 366 } 367 368 static void multiport_print_v1(const void *ip_void, 369 const struct xt_entry_match *match, int numeric) 370 { 371 const struct ipt_ip *ip = ip_void; 372 __multiport_print_v1(match, numeric, ip->proto); 373 } 374 375 static void multiport_print6_v1(const void *ip_void, 376 const struct xt_entry_match *match, int numeric) 377 { 378 const struct ip6t_ip6 *ip = ip_void; 379 __multiport_print_v1(match, numeric, ip->proto); 380 } 381 382 static void __multiport_save(const struct xt_entry_match *match, 383 uint16_t proto) 384 { 385 const struct xt_multiport *multiinfo 386 = (const struct xt_multiport *)match->data; 387 unsigned int i; 388 389 switch (multiinfo->flags) { 390 case XT_MULTIPORT_SOURCE: 391 printf(" --sports "); 392 break; 393 394 case XT_MULTIPORT_DESTINATION: 395 printf(" --dports "); 396 break; 397 398 case XT_MULTIPORT_EITHER: 399 printf(" --ports "); 400 break; 401 } 402 403 for (i=0; i < multiinfo->count; i++) { 404 printf("%s", i ? "," : ""); 405 print_port(multiinfo->ports[i], proto, 1); 406 } 407 } 408 409 static void multiport_save(const void *ip_void, 410 const struct xt_entry_match *match) 411 { 412 const struct ipt_ip *ip = ip_void; 413 __multiport_save(match, ip->proto); 414 } 415 416 static void multiport_save6(const void *ip_void, 417 const struct xt_entry_match *match) 418 { 419 const struct ip6t_ip6 *ip = ip_void; 420 __multiport_save(match, ip->proto); 421 } 422 423 static void __multiport_save_v1(const struct xt_entry_match *match, 424 uint16_t proto) 425 { 426 const struct xt_multiport_v1 *multiinfo 427 = (const struct xt_multiport_v1 *)match->data; 428 unsigned int i; 429 430 if (multiinfo->invert) 431 printf(" !"); 432 433 switch (multiinfo->flags) { 434 case XT_MULTIPORT_SOURCE: 435 printf(" --sports "); 436 break; 437 438 case XT_MULTIPORT_DESTINATION: 439 printf(" --dports "); 440 break; 441 442 case XT_MULTIPORT_EITHER: 443 printf(" --ports "); 444 break; 445 } 446 447 for (i=0; i < multiinfo->count; i++) { 448 printf("%s", i ? "," : ""); 449 print_port(multiinfo->ports[i], proto, 1); 450 if (multiinfo->pflags[i]) { 451 printf(":"); 452 print_port(multiinfo->ports[++i], proto, 1); 453 } 454 } 455 } 456 457 static void multiport_save_v1(const void *ip_void, 458 const struct xt_entry_match *match) 459 { 460 const struct ipt_ip *ip = ip_void; 461 __multiport_save_v1(match, ip->proto); 462 } 463 464 static void multiport_save6_v1(const void *ip_void, 465 const struct xt_entry_match *match) 466 { 467 const struct ip6t_ip6 *ip = ip_void; 468 __multiport_save_v1(match, ip->proto); 469 } 470 471 static struct xtables_match multiport_mt_reg[] = { 472 { 473 .family = NFPROTO_IPV4, 474 .name = "multiport", 475 .revision = 0, 476 .version = XTABLES_VERSION, 477 .size = XT_ALIGN(sizeof(struct xt_multiport)), 478 .userspacesize = XT_ALIGN(sizeof(struct xt_multiport)), 479 .help = multiport_help, 480 .x6_parse = multiport_parse, 481 .x6_fcheck = multiport_check, 482 .print = multiport_print, 483 .save = multiport_save, 484 .x6_options = multiport_opts, 485 }, 486 { 487 .family = NFPROTO_IPV6, 488 .name = "multiport", 489 .revision = 0, 490 .version = XTABLES_VERSION, 491 .size = XT_ALIGN(sizeof(struct xt_multiport)), 492 .userspacesize = XT_ALIGN(sizeof(struct xt_multiport)), 493 .help = multiport_help, 494 .x6_parse = multiport_parse6, 495 .x6_fcheck = multiport_check, 496 .print = multiport_print6, 497 .save = multiport_save6, 498 .x6_options = multiport_opts, 499 }, 500 { 501 .family = NFPROTO_IPV4, 502 .name = "multiport", 503 .version = XTABLES_VERSION, 504 .revision = 1, 505 .size = XT_ALIGN(sizeof(struct xt_multiport_v1)), 506 .userspacesize = XT_ALIGN(sizeof(struct xt_multiport_v1)), 507 .help = multiport_help_v1, 508 .x6_parse = multiport_parse_v1, 509 .x6_fcheck = multiport_check, 510 .print = multiport_print_v1, 511 .save = multiport_save_v1, 512 .x6_options = multiport_opts, 513 }, 514 { 515 .family = NFPROTO_IPV6, 516 .name = "multiport", 517 .version = XTABLES_VERSION, 518 .revision = 1, 519 .size = XT_ALIGN(sizeof(struct xt_multiport_v1)), 520 .userspacesize = XT_ALIGN(sizeof(struct xt_multiport_v1)), 521 .help = multiport_help_v1, 522 .x6_parse = multiport_parse6_v1, 523 .x6_fcheck = multiport_check, 524 .print = multiport_print6_v1, 525 .save = multiport_save6_v1, 526 .x6_options = multiport_opts, 527 }, 528 }; 529 530 void 531 _init(void) 532 { 533 xtables_register_matches(multiport_mt_reg, ARRAY_SIZE(multiport_mt_reg)); 534 } 535