xtables.h revision df60a301bf24c3b3e37188d9da155b97fd6dc076
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 36struct 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 */ 73enum 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 */ 106enum 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 */ 126struct 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 */ 147struct 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 */ 188struct 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 */ 198struct xtables_lmap { 199 char *name; 200 int id; 201 struct xtables_lmap *next; 202}; 203 204/* Include file for additions: new matches and targets. */ 205struct xtables_match 206{ 207 /* 208 * ABI/API version this module requires. Must be first member, 209 * as the rest of this struct may be subject to ABI changes. 210 */ 211 const char *version; 212 213 struct xtables_match *next; 214 215 const char *name; 216 217 /* Revision of match (0 by default). */ 218 u_int8_t revision; 219 220 u_int16_t family; 221 222 /* Size of match data. */ 223 size_t size; 224 225 /* Size of match data relevent for userspace comparison purposes */ 226 size_t userspacesize; 227 228 /* Function which prints out usage message. */ 229 void (*help)(void); 230 231 /* Initialize the match. */ 232 void (*init)(struct xt_entry_match *m); 233 234 /* Function which parses command options; returns true if it 235 ate an option */ 236 /* entry is struct ipt_entry for example */ 237 int (*parse)(int c, char **argv, int invert, unsigned int *flags, 238 const void *entry, 239 struct xt_entry_match **match); 240 241 /* Final check; exit if not ok. */ 242 void (*final_check)(unsigned int flags); 243 244 /* Prints out the match iff non-NULL: put space at end */ 245 /* ip is struct ipt_ip * for example */ 246 void (*print)(const void *ip, 247 const struct xt_entry_match *match, int numeric); 248 249 /* Saves the match info in parsable form to stdout. */ 250 /* ip is struct ipt_ip * for example */ 251 void (*save)(const void *ip, const struct xt_entry_match *match); 252 253 /* Pointer to list of extra command-line options */ 254 const struct option *extra_opts; 255 256 /* New parser */ 257 void (*x6_parse)(struct xt_option_call *); 258 void (*x6_fcheck)(struct xt_fcheck_call *); 259 const struct xt_option_entry *x6_options; 260 261 /* Size of per-extension instance extra "global" scratch space */ 262 size_t udata_size; 263 264 /* Ignore these men behind the curtain: */ 265 void *udata; 266 unsigned int option_offset; 267 struct xt_entry_match *m; 268 unsigned int mflags; 269 unsigned int loaded; /* simulate loading so options are merged properly */ 270}; 271 272struct xtables_target 273{ 274 /* 275 * ABI/API version this module requires. Must be first member, 276 * as the rest of this struct may be subject to ABI changes. 277 */ 278 const char *version; 279 280 struct xtables_target *next; 281 282 283 const char *name; 284 285 /* Revision of target (0 by default). */ 286 u_int8_t revision; 287 288 u_int16_t family; 289 290 291 /* Size of target data. */ 292 size_t size; 293 294 /* Size of target data relevent for userspace comparison purposes */ 295 size_t userspacesize; 296 297 /* Function which prints out usage message. */ 298 void (*help)(void); 299 300 /* Initialize the target. */ 301 void (*init)(struct xt_entry_target *t); 302 303 /* Function which parses command options; returns true if it 304 ate an option */ 305 /* entry is struct ipt_entry for example */ 306 int (*parse)(int c, char **argv, int invert, unsigned int *flags, 307 const void *entry, 308 struct xt_entry_target **targetinfo); 309 310 /* Final check; exit if not ok. */ 311 void (*final_check)(unsigned int flags); 312 313 /* Prints out the target iff non-NULL: put space at end */ 314 void (*print)(const void *ip, 315 const struct xt_entry_target *target, int numeric); 316 317 /* Saves the targinfo in parsable form to stdout. */ 318 void (*save)(const void *ip, 319 const struct xt_entry_target *target); 320 321 /* Pointer to list of extra command-line options */ 322 const struct option *extra_opts; 323 324 /* New parser */ 325 void (*x6_parse)(struct xt_option_call *); 326 void (*x6_fcheck)(struct xt_fcheck_call *); 327 const struct xt_option_entry *x6_options; 328 329 size_t udata_size; 330 331 /* Ignore these men behind the curtain: */ 332 void *udata; 333 unsigned int option_offset; 334 struct xt_entry_target *t; 335 unsigned int tflags; 336 unsigned int used; 337 unsigned int loaded; /* simulate loading so options are merged properly */ 338}; 339 340struct xtables_rule_match { 341 struct xtables_rule_match *next; 342 struct xtables_match *match; 343 /* Multiple matches of the same type: the ones before 344 the current one are completed from parsing point of view */ 345 bool completed; 346}; 347 348/** 349 * struct xtables_pprot - 350 * 351 * A few hardcoded protocols for 'all' and in case the user has no 352 * /etc/protocols. 353 */ 354struct xtables_pprot { 355 const char *name; 356 u_int8_t num; 357}; 358 359enum xtables_tryload { 360 XTF_DONT_LOAD, 361 XTF_DURING_LOAD, 362 XTF_TRY_LOAD, 363 XTF_LOAD_MUST_SUCCEED, 364}; 365 366enum xtables_exittype { 367 OTHER_PROBLEM = 1, 368 PARAMETER_PROBLEM, 369 VERSION_PROBLEM, 370 RESOURCE_PROBLEM, 371 XTF_ONLY_ONCE, 372 XTF_NO_INVERT, 373 XTF_BAD_VALUE, 374 XTF_ONE_ACTION, 375}; 376 377struct xtables_globals 378{ 379 unsigned int option_offset; 380 const char *program_name, *program_version; 381 struct option *orig_opts; 382 struct option *opts; 383 void (*exit_err)(enum xtables_exittype status, const char *msg, ...) __attribute__((noreturn, format(printf,2,3))); 384}; 385 386#define XT_GETOPT_TABLEEND {.name = NULL, .has_arg = false} 387 388#ifdef __cplusplus 389extern "C" { 390#endif 391 392extern const char *xtables_modprobe_program; 393extern struct xtables_match *xtables_matches; 394extern struct xtables_target *xtables_targets; 395 396extern void xtables_init(void); 397extern void xtables_set_nfproto(uint8_t); 398extern void *xtables_calloc(size_t, size_t); 399extern void *xtables_malloc(size_t); 400extern void *xtables_realloc(void *, size_t); 401 402extern int xtables_insmod(const char *, const char *, bool); 403extern int xtables_load_ko(const char *, bool); 404extern int xtables_set_params(struct xtables_globals *xtp); 405extern void xtables_free_opts(int reset_offset); 406extern struct option *xtables_merge_options(struct option *origopts, 407 struct option *oldopts, const struct option *newopts, 408 unsigned int *option_offset); 409 410extern int xtables_init_all(struct xtables_globals *xtp, uint8_t nfproto); 411extern struct xtables_match *xtables_find_match(const char *name, 412 enum xtables_tryload, struct xtables_rule_match **match); 413extern struct xtables_target *xtables_find_target(const char *name, 414 enum xtables_tryload); 415 416/* Your shared library should call one of these. */ 417extern void xtables_register_match(struct xtables_match *me); 418extern void xtables_register_matches(struct xtables_match *, unsigned int); 419extern void xtables_register_target(struct xtables_target *me); 420extern void xtables_register_targets(struct xtables_target *, unsigned int); 421 422extern bool xtables_strtoul(const char *, char **, uintmax_t *, 423 uintmax_t, uintmax_t); 424extern bool xtables_strtoui(const char *, char **, unsigned int *, 425 unsigned int, unsigned int); 426extern int xtables_service_to_port(const char *name, const char *proto); 427extern u_int16_t xtables_parse_port(const char *port, const char *proto); 428extern void 429xtables_parse_interface(const char *arg, char *vianame, unsigned char *mask); 430 431/* this is a special 64bit data type that is 8-byte aligned */ 432#define aligned_u64 u_int64_t __attribute__((aligned(8))) 433 434extern struct xtables_globals *xt_params; 435#define xtables_error (xt_params->exit_err) 436 437extern void xtables_param_act(unsigned int, const char *, ...); 438 439extern const char *xtables_ipaddr_to_numeric(const struct in_addr *); 440extern const char *xtables_ipaddr_to_anyname(const struct in_addr *); 441extern const char *xtables_ipmask_to_numeric(const struct in_addr *); 442extern struct in_addr *xtables_numeric_to_ipaddr(const char *); 443extern struct in_addr *xtables_numeric_to_ipmask(const char *); 444extern int xtables_ipmask_to_cidr(const struct in_addr *); 445extern void xtables_ipparse_any(const char *, struct in_addr **, 446 struct in_addr *, unsigned int *); 447extern void xtables_ipparse_multiple(const char *, struct in_addr **, 448 struct in_addr **, unsigned int *); 449 450extern struct in6_addr *xtables_numeric_to_ip6addr(const char *); 451extern const char *xtables_ip6addr_to_numeric(const struct in6_addr *); 452extern const char *xtables_ip6addr_to_anyname(const struct in6_addr *); 453extern const char *xtables_ip6mask_to_numeric(const struct in6_addr *); 454extern int xtables_ip6mask_to_cidr(const struct in6_addr *); 455extern void xtables_ip6parse_any(const char *, struct in6_addr **, 456 struct in6_addr *, unsigned int *); 457extern void xtables_ip6parse_multiple(const char *, struct in6_addr **, 458 struct in6_addr **, unsigned int *); 459 460/** 461 * Print the specified value to standard output, quoting dangerous 462 * characters if required. 463 */ 464extern void xtables_save_string(const char *value); 465 466#if defined(ALL_INCLUSIVE) || defined(NO_SHARED_LIBS) 467# ifdef _INIT 468# undef _init 469# define _init _INIT 470# endif 471 extern void init_extensions(void); 472 extern void init_extensions4(void); 473 extern void init_extensions6(void); 474#else 475# define _init __attribute__((constructor)) _INIT 476#endif 477 478extern const struct xtables_pprot xtables_chain_protos[]; 479extern u_int16_t xtables_parse_protocol(const char *s); 480 481/* kernel revision handling */ 482extern int kernel_version; 483extern void get_kernel_version(void); 484#define LINUX_VERSION(x,y,z) (0x10000*(x) + 0x100*(y) + z) 485#define LINUX_VERSION_MAJOR(x) (((x)>>16) & 0xFF) 486#define LINUX_VERSION_MINOR(x) (((x)>> 8) & 0xFF) 487#define LINUX_VERSION_PATCH(x) ( (x) & 0xFF) 488 489/* xtoptions.c */ 490extern void xtables_option_metavalidate(const char *, 491 const struct xt_option_entry *); 492extern struct option *xtables_options_xfrm(struct option *, struct option *, 493 const struct xt_option_entry *, 494 unsigned int *); 495extern void xtables_option_parse(struct xt_option_call *); 496extern void xtables_option_tpcall(unsigned int, char **, bool, 497 struct xtables_target *, void *); 498extern void xtables_option_mpcall(unsigned int, char **, bool, 499 struct xtables_match *, void *); 500extern void xtables_option_tfcall(struct xtables_target *); 501extern void xtables_option_mfcall(struct xtables_match *); 502extern void xtables_options_fcheck(const char *, unsigned int, 503 const struct xt_option_entry *); 504 505extern struct xtables_lmap *xtables_lmap_init(const char *); 506extern void xtables_lmap_free(struct xtables_lmap *); 507extern int xtables_lmap_name2id(const struct xtables_lmap *, const char *); 508extern const char *xtables_lmap_id2name(const struct xtables_lmap *, int); 509 510#ifdef XTABLES_INTERNAL 511 512/* Shipped modules rely on this... */ 513 514# ifndef ARRAY_SIZE 515# define ARRAY_SIZE(x) (sizeof(x) / sizeof(*(x))) 516# endif 517 518extern void _init(void); 519 520#endif 521 522#ifdef __cplusplus 523} /* extern "C" */ 524#endif 525 526#endif /* _XTABLES_H */ 527