1 #ifndef _XTABLES_H 2 #define _XTABLES_H 3 4 /* 5 * Changing any structs/functions may incur a needed change 6 * in libxtables_vcurrent/vage too. 7 */ 8 9 #include <sys/socket.h> /* PF_* */ 10 #include <sys/types.h> 11 #include <limits.h> 12 #include <stdbool.h> 13 #include <stddef.h> 14 #include <stdint.h> 15 #include <netinet/in.h> 16 #include <net/if.h> 17 #include <linux/types.h> 18 #include <linux/netfilter.h> 19 #include <linux/netfilter/x_tables.h> 20 21 #ifndef IPPROTO_SCTP 22 #define IPPROTO_SCTP 132 23 #endif 24 #ifndef IPPROTO_DCCP 25 #define IPPROTO_DCCP 33 26 #endif 27 #ifndef IPPROTO_MH 28 # define IPPROTO_MH 135 29 #endif 30 #ifndef IPPROTO_UDPLITE 31 #define IPPROTO_UDPLITE 136 32 #endif 33 34 #include <xtables-version.h> 35 36 struct in_addr; 37 38 /* 39 * .size is here so that there is a somewhat reasonable check 40 * against the chosen .type. 41 */ 42 #define XTOPT_POINTER(stype, member) \ 43 .ptroff = offsetof(stype, member), \ 44 .size = sizeof(((stype *)NULL)->member) 45 #define XTOPT_TABLEEND {.name = NULL} 46 47 /** 48 * Select the format the input has to conform to, as well as the target type 49 * (area pointed to with XTOPT_POINTER). Note that the storing is not always 50 * uniform. @cb->val will be populated with as much as there is space, i.e. 51 * exactly 2 items for ranges, but the target area can receive more values 52 * (e.g. in case of ranges), or less values (e.g. %XTTYPE_HOSTMASK). 53 * 54 * %XTTYPE_NONE: option takes no argument 55 * %XTTYPE_UINT*: standard integer 56 * %XTTYPE_UINT*RC: colon-separated range of standard integers 57 * %XTTYPE_DOUBLE: double-precision floating point number 58 * %XTTYPE_STRING: arbitrary string 59 * %XTTYPE_TOSMASK: 8-bit TOS value with optional mask 60 * %XTTYPE_MARKMASK32: 32-bit mark with optional mask 61 * %XTTYPE_SYSLOGLEVEL: syslog level by name or number 62 * %XTTYPE_HOST: one host or address (ptr: union nf_inet_addr) 63 * %XTTYPE_HOSTMASK: one host or address, with an optional prefix length 64 * (ptr: union nf_inet_addr; only host portion is stored) 65 * %XTTYPE_PROTOCOL: protocol number/name from /etc/protocols (ptr: uint8_t) 66 * %XTTYPE_PORT: 16-bit port name or number (supports %XTOPT_NBO) 67 * %XTTYPE_PORTRC: colon-separated port range (names acceptable), 68 * (supports %XTOPT_NBO) 69 * %XTTYPE_PLEN: prefix length 70 * %XTTYPE_PLENMASK: prefix length (ptr: union nf_inet_addr) 71 * %XTTYPE_ETHERMAC: Ethernet MAC address in hex form 72 */ 73 enum xt_option_type { 74 XTTYPE_NONE, 75 XTTYPE_UINT8, 76 XTTYPE_UINT16, 77 XTTYPE_UINT32, 78 XTTYPE_UINT64, 79 XTTYPE_UINT8RC, 80 XTTYPE_UINT16RC, 81 XTTYPE_UINT32RC, 82 XTTYPE_UINT64RC, 83 XTTYPE_DOUBLE, 84 XTTYPE_STRING, 85 XTTYPE_TOSMASK, 86 XTTYPE_MARKMASK32, 87 XTTYPE_SYSLOGLEVEL, 88 XTTYPE_HOST, 89 XTTYPE_HOSTMASK, 90 XTTYPE_PROTOCOL, 91 XTTYPE_PORT, 92 XTTYPE_PORTRC, 93 XTTYPE_PLEN, 94 XTTYPE_PLENMASK, 95 XTTYPE_ETHERMAC, 96 }; 97 98 /** 99 * %XTOPT_INVERT: option is invertible (usable with !) 100 * %XTOPT_MAND: option is mandatory 101 * %XTOPT_MULTI: option may be specified multiple times 102 * %XTOPT_PUT: store value into memory at @ptroff 103 * %XTOPT_NBO: store value in network-byte order 104 * (only certain XTTYPEs recognize this) 105 */ 106 enum xt_option_flags { 107 XTOPT_INVERT = 1 << 0, 108 XTOPT_MAND = 1 << 1, 109 XTOPT_MULTI = 1 << 2, 110 XTOPT_PUT = 1 << 3, 111 XTOPT_NBO = 1 << 4, 112 }; 113 114 /** 115 * @name: name of option 116 * @type: type of input and validation method, see %XTTYPE_* 117 * @id: unique number (within extension) for option, 0-31 118 * @excl: bitmask of flags that cannot be used with this option 119 * @also: bitmask of flags that must be used with this option 120 * @flags: bitmask of option flags, see %XTOPT_* 121 * @ptroff: offset into private structure for member 122 * @size: size of the item pointed to by @ptroff; this is a safeguard 123 * @min: lowest allowed value (for singular integral types) 124 * @max: highest allowed value (for singular integral types) 125 */ 126 struct xt_option_entry { 127 const char *name; 128 enum xt_option_type type; 129 unsigned int id, excl, also, flags; 130 unsigned int ptroff; 131 size_t size; 132 unsigned int min, max; 133 }; 134 135 /** 136 * @arg: input from command line 137 * @ext_name: name of extension currently being processed 138 * @entry: current option being processed 139 * @data: per-extension kernel data block 140 * @xflags: options of the extension that have been used 141 * @invert: whether option was used with ! 142 * @nvals: number of results in uXX_multi 143 * @val: parsed result 144 * @udata: per-extension private scratch area 145 * (cf. xtables_{match,target}->udata_size) 146 */ 147 struct xt_option_call { 148 const char *arg, *ext_name; 149 const struct xt_option_entry *entry; 150 void *data; 151 unsigned int xflags; 152 bool invert; 153 uint8_t nvals; 154 union { 155 uint8_t u8, u8_range[2], syslog_level, protocol; 156 uint16_t u16, u16_range[2], port, port_range[2]; 157 uint32_t u32, u32_range[2]; 158 uint64_t u64, u64_range[2]; 159 double dbl; 160 struct { 161 union nf_inet_addr haddr, hmask; 162 uint8_t hlen; 163 }; 164 struct { 165 uint8_t tos_value, tos_mask; 166 }; 167 struct { 168 uint32_t mark, mask; 169 }; 170 uint8_t ethermac[6]; 171 } val; 172 /* Wished for a world where the ones below were gone: */ 173 union { 174 struct xt_entry_match **match; 175 struct xt_entry_target **target; 176 }; 177 void *xt_entry; 178 void *udata; 179 }; 180 181 /** 182 * @ext_name: name of extension currently being processed 183 * @data: per-extension (kernel) data block 184 * @udata: per-extension private scratch area 185 * (cf. xtables_{match,target}->udata_size) 186 * @xflags: options of the extension that have been used 187 */ 188 struct xt_fcheck_call { 189 const char *ext_name; 190 void *data, *udata; 191 unsigned int xflags; 192 }; 193 194 /** 195 * A "linear"/linked-list based name<->id map, for files similar to 196 * /etc/iproute2/. 197 */ 198 struct xtables_lmap { 199 char *name; 200 int id; 201 struct xtables_lmap *next; 202 }; 203 204 enum xtables_ext_flags { 205 XTABLES_EXT_ALIAS = 1 << 0, 206 }; 207 208 /* Include file for additions: new matches and targets. */ 209 struct xtables_match 210 { 211 /* 212 * ABI/API version this module requires. Must be first member, 213 * as the rest of this struct may be subject to ABI changes. 214 */ 215 const char *version; 216 217 struct xtables_match *next; 218 219 const char *name; 220 const char *real_name; 221 222 /* Revision of match (0 by default). */ 223 u_int8_t revision; 224 225 /* Extension flags */ 226 u_int8_t ext_flags; 227 228 u_int16_t family; 229 230 /* Size of match data. */ 231 size_t size; 232 233 /* Size of match data relevent for userspace comparison purposes */ 234 size_t userspacesize; 235 236 /* Function which prints out usage message. */ 237 void (*help)(void); 238 239 /* Initialize the match. */ 240 void (*init)(struct xt_entry_match *m); 241 242 /* Function which parses command options; returns true if it 243 ate an option */ 244 /* entry is struct ipt_entry for example */ 245 int (*parse)(int c, char **argv, int invert, unsigned int *flags, 246 const void *entry, 247 struct xt_entry_match **match); 248 249 /* Final check; exit if not ok. */ 250 void (*final_check)(unsigned int flags); 251 252 /* Prints out the match iff non-NULL: put space at end */ 253 /* ip is struct ipt_ip * for example */ 254 void (*print)(const void *ip, 255 const struct xt_entry_match *match, int numeric); 256 257 /* Saves the match info in parsable form to stdout. */ 258 /* ip is struct ipt_ip * for example */ 259 void (*save)(const void *ip, const struct xt_entry_match *match); 260 261 /* Print match name or alias */ 262 const char *(*alias)(const struct xt_entry_match *match); 263 264 /* Pointer to list of extra command-line options */ 265 const struct option *extra_opts; 266 267 /* New parser */ 268 void (*x6_parse)(struct xt_option_call *); 269 void (*x6_fcheck)(struct xt_fcheck_call *); 270 const struct xt_option_entry *x6_options; 271 272 /* Size of per-extension instance extra "global" scratch space */ 273 size_t udata_size; 274 275 /* Ignore these men behind the curtain: */ 276 void *udata; 277 unsigned int option_offset; 278 struct xt_entry_match *m; 279 unsigned int mflags; 280 unsigned int loaded; /* simulate loading so options are merged properly */ 281 }; 282 283 struct xtables_target 284 { 285 /* 286 * ABI/API version this module requires. Must be first member, 287 * as the rest of this struct may be subject to ABI changes. 288 */ 289 const char *version; 290 291 struct xtables_target *next; 292 293 294 const char *name; 295 296 /* Real target behind this, if any. */ 297 const char *real_name; 298 299 /* Revision of target (0 by default). */ 300 u_int8_t revision; 301 302 /* Extension flags */ 303 u_int8_t ext_flags; 304 305 u_int16_t family; 306 307 308 /* Size of target data. */ 309 size_t size; 310 311 /* Size of target data relevent for userspace comparison purposes */ 312 size_t userspacesize; 313 314 /* Function which prints out usage message. */ 315 void (*help)(void); 316 317 /* Initialize the target. */ 318 void (*init)(struct xt_entry_target *t); 319 320 /* Function which parses command options; returns true if it 321 ate an option */ 322 /* entry is struct ipt_entry for example */ 323 int (*parse)(int c, char **argv, int invert, unsigned int *flags, 324 const void *entry, 325 struct xt_entry_target **targetinfo); 326 327 /* Final check; exit if not ok. */ 328 void (*final_check)(unsigned int flags); 329 330 /* Prints out the target iff non-NULL: put space at end */ 331 void (*print)(const void *ip, 332 const struct xt_entry_target *target, int numeric); 333 334 /* Saves the targinfo in parsable form to stdout. */ 335 void (*save)(const void *ip, 336 const struct xt_entry_target *target); 337 338 /* Print target name or alias */ 339 const char *(*alias)(const struct xt_entry_target *target); 340 341 /* Pointer to list of extra command-line options */ 342 const struct option *extra_opts; 343 344 /* New parser */ 345 void (*x6_parse)(struct xt_option_call *); 346 void (*x6_fcheck)(struct xt_fcheck_call *); 347 const struct xt_option_entry *x6_options; 348 349 size_t udata_size; 350 351 /* Ignore these men behind the curtain: */ 352 void *udata; 353 unsigned int option_offset; 354 struct xt_entry_target *t; 355 unsigned int tflags; 356 unsigned int used; 357 unsigned int loaded; /* simulate loading so options are merged properly */ 358 }; 359 360 struct xtables_rule_match { 361 struct xtables_rule_match *next; 362 struct xtables_match *match; 363 /* Multiple matches of the same type: the ones before 364 the current one are completed from parsing point of view */ 365 bool completed; 366 }; 367 368 /** 369 * struct xtables_pprot - 370 * 371 * A few hardcoded protocols for 'all' and in case the user has no 372 * /etc/protocols. 373 */ 374 struct xtables_pprot { 375 const char *name; 376 u_int8_t num; 377 }; 378 379 enum xtables_tryload { 380 XTF_DONT_LOAD, 381 XTF_DURING_LOAD, 382 XTF_TRY_LOAD, 383 XTF_LOAD_MUST_SUCCEED, 384 }; 385 386 enum xtables_exittype { 387 OTHER_PROBLEM = 1, 388 PARAMETER_PROBLEM, 389 VERSION_PROBLEM, 390 RESOURCE_PROBLEM, 391 XTF_ONLY_ONCE, 392 XTF_NO_INVERT, 393 XTF_BAD_VALUE, 394 XTF_ONE_ACTION, 395 }; 396 397 struct xtables_globals 398 { 399 unsigned int option_offset; 400 const char *program_name, *program_version; 401 struct option *orig_opts; 402 struct option *opts; 403 void (*exit_err)(enum xtables_exittype status, const char *msg, ...) __attribute__((noreturn, format(printf,2,3))); 404 }; 405 406 #define XT_GETOPT_TABLEEND {.name = NULL, .has_arg = false} 407 408 #ifdef __cplusplus 409 extern "C" { 410 #endif 411 412 extern const char *xtables_modprobe_program; 413 extern struct xtables_match *xtables_matches; 414 extern struct xtables_target *xtables_targets; 415 416 extern void xtables_init(void); 417 extern void xtables_set_nfproto(uint8_t); 418 extern void *xtables_calloc(size_t, size_t); 419 extern void *xtables_malloc(size_t); 420 extern void *xtables_realloc(void *, size_t); 421 422 extern int xtables_insmod(const char *, const char *, bool); 423 extern int xtables_load_ko(const char *, bool); 424 extern int xtables_set_params(struct xtables_globals *xtp); 425 extern void xtables_free_opts(int reset_offset); 426 extern struct option *xtables_merge_options(struct option *origopts, 427 struct option *oldopts, const struct option *newopts, 428 unsigned int *option_offset); 429 430 extern int xtables_init_all(struct xtables_globals *xtp, uint8_t nfproto); 431 extern struct xtables_match *xtables_find_match(const char *name, 432 enum xtables_tryload, struct xtables_rule_match **match); 433 extern struct xtables_target *xtables_find_target(const char *name, 434 enum xtables_tryload); 435 436 extern void xtables_rule_matches_free(struct xtables_rule_match **matches); 437 438 /* Your shared library should call one of these. */ 439 extern void xtables_register_match(struct xtables_match *me); 440 extern void xtables_register_matches(struct xtables_match *, unsigned int); 441 extern void xtables_register_target(struct xtables_target *me); 442 extern void xtables_register_targets(struct xtables_target *, unsigned int); 443 444 extern bool xtables_strtoul(const char *, char **, uintmax_t *, 445 uintmax_t, uintmax_t); 446 extern bool xtables_strtoui(const char *, char **, unsigned int *, 447 unsigned int, unsigned int); 448 extern int xtables_service_to_port(const char *name, const char *proto); 449 extern u_int16_t xtables_parse_port(const char *port, const char *proto); 450 extern void 451 xtables_parse_interface(const char *arg, char *vianame, unsigned char *mask); 452 453 /* this is a special 64bit data type that is 8-byte aligned */ 454 #define aligned_u64 u_int64_t __attribute__((aligned(8))) 455 456 extern struct xtables_globals *xt_params; 457 #define xtables_error (xt_params->exit_err) 458 459 extern void xtables_param_act(unsigned int, const char *, ...); 460 461 extern const char *xtables_ipaddr_to_numeric(const struct in_addr *); 462 extern const char *xtables_ipaddr_to_anyname(const struct in_addr *); 463 extern const char *xtables_ipmask_to_numeric(const struct in_addr *); 464 extern struct in_addr *xtables_numeric_to_ipaddr(const char *); 465 extern struct in_addr *xtables_numeric_to_ipmask(const char *); 466 extern int xtables_ipmask_to_cidr(const struct in_addr *); 467 extern void xtables_ipparse_any(const char *, struct in_addr **, 468 struct in_addr *, unsigned int *); 469 extern void xtables_ipparse_multiple(const char *, struct in_addr **, 470 struct in_addr **, unsigned int *); 471 472 extern struct in6_addr *xtables_numeric_to_ip6addr(const char *); 473 extern const char *xtables_ip6addr_to_numeric(const struct in6_addr *); 474 extern const char *xtables_ip6addr_to_anyname(const struct in6_addr *); 475 extern const char *xtables_ip6mask_to_numeric(const struct in6_addr *); 476 extern int xtables_ip6mask_to_cidr(const struct in6_addr *); 477 extern void xtables_ip6parse_any(const char *, struct in6_addr **, 478 struct in6_addr *, unsigned int *); 479 extern void xtables_ip6parse_multiple(const char *, struct in6_addr **, 480 struct in6_addr **, unsigned int *); 481 482 /** 483 * Print the specified value to standard output, quoting dangerous 484 * characters if required. 485 */ 486 extern void xtables_save_string(const char *value); 487 488 #define FMT_NUMERIC 0x0001 489 #define FMT_NOCOUNTS 0x0002 490 #define FMT_KILOMEGAGIGA 0x0004 491 #define FMT_OPTIONS 0x0008 492 #define FMT_NOTABLE 0x0010 493 #define FMT_NOTARGET 0x0020 494 #define FMT_VIA 0x0040 495 #define FMT_NONEWLINE 0x0080 496 #define FMT_LINENUMBERS 0x0100 497 498 #define FMT_PRINT_RULE (FMT_NOCOUNTS | FMT_OPTIONS | FMT_VIA \ 499 | FMT_NUMERIC | FMT_NOTABLE) 500 #define FMT(tab,notab) ((format) & FMT_NOTABLE ? (notab) : (tab)) 501 502 extern void xtables_print_num(uint64_t number, unsigned int format); 503 504 #if defined(ALL_INCLUSIVE) || defined(NO_SHARED_LIBS) 505 # ifdef _INIT 506 # undef _init 507 # define _init _INIT 508 # endif 509 extern void init_extensions(void); 510 extern void init_extensions4(void); 511 extern void init_extensions6(void); 512 #else 513 # define _init __attribute__((constructor)) _INIT 514 #endif 515 516 extern const struct xtables_pprot xtables_chain_protos[]; 517 extern u_int16_t xtables_parse_protocol(const char *s); 518 519 /* kernel revision handling */ 520 extern int kernel_version; 521 extern void get_kernel_version(void); 522 #define LINUX_VERSION(x,y,z) (0x10000*(x) + 0x100*(y) + z) 523 #define LINUX_VERSION_MAJOR(x) (((x)>>16) & 0xFF) 524 #define LINUX_VERSION_MINOR(x) (((x)>> 8) & 0xFF) 525 #define LINUX_VERSION_PATCH(x) ( (x) & 0xFF) 526 527 /* xtoptions.c */ 528 extern void xtables_option_metavalidate(const char *, 529 const struct xt_option_entry *); 530 extern struct option *xtables_options_xfrm(struct option *, struct option *, 531 const struct xt_option_entry *, 532 unsigned int *); 533 extern void xtables_option_parse(struct xt_option_call *); 534 extern void xtables_option_tpcall(unsigned int, char **, bool, 535 struct xtables_target *, void *); 536 extern void xtables_option_mpcall(unsigned int, char **, bool, 537 struct xtables_match *, void *); 538 extern void xtables_option_tfcall(struct xtables_target *); 539 extern void xtables_option_mfcall(struct xtables_match *); 540 extern void xtables_options_fcheck(const char *, unsigned int, 541 const struct xt_option_entry *); 542 543 extern struct xtables_lmap *xtables_lmap_init(const char *); 544 extern void xtables_lmap_free(struct xtables_lmap *); 545 extern int xtables_lmap_name2id(const struct xtables_lmap *, const char *); 546 extern const char *xtables_lmap_id2name(const struct xtables_lmap *, int); 547 548 #ifdef XTABLES_INTERNAL 549 550 /* Shipped modules rely on this... */ 551 552 # ifndef ARRAY_SIZE 553 # define ARRAY_SIZE(x) (sizeof(x) / sizeof(*(x))) 554 # endif 555 556 extern void _init(void); 557 558 #endif 559 560 #ifdef __cplusplus 561 } /* extern "C" */ 562 #endif 563 564 #endif /* _XTABLES_H */ 565