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Diffstat (limited to '')
| -rw-r--r-- | include/xtables.h | 598 |
1 files changed, 598 insertions, 0 deletions
diff --git a/include/xtables.h b/include/xtables.h new file mode 100644 index 0000000..583619f --- /dev/null +++ b/include/xtables.h @@ -0,0 +1,598 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _XTABLES_H +#define _XTABLES_H + +/* + * Changing any structs/functions may incur a needed change + * in libxtables_vcurrent/vage too. + */ + +#include <sys/socket.h> /* PF_* */ +#include <sys/types.h> +#include <limits.h> +#include <stdbool.h> +#include <stddef.h> +#include <stdint.h> +#include <netinet/in.h> +#include <net/if.h> +#include <linux/types.h> +#include <linux/netfilter.h> +#include <linux/netfilter/x_tables.h> + +#ifndef IPPROTO_SCTP +#define IPPROTO_SCTP 132 +#endif +#ifndef IPPROTO_DCCP +#define IPPROTO_DCCP 33 +#endif +#ifndef IPPROTO_MH +# define IPPROTO_MH 135 +#endif +#ifndef IPPROTO_UDPLITE +#define IPPROTO_UDPLITE 136 +#endif + +#include <xtables-version.h> + +struct in_addr; + +/* + * .size is here so that there is a somewhat reasonable check + * against the chosen .type. + */ +#define XTOPT_POINTER(stype, member) \ + .ptroff = offsetof(stype, member), \ + .size = sizeof(((stype *)NULL)->member) +#define XTOPT_TABLEEND {.name = NULL} + +/** + * Select the format the input has to conform to, as well as the target type + * (area pointed to with XTOPT_POINTER). Note that the storing is not always + * uniform. @cb->val will be populated with as much as there is space, i.e. + * exactly 2 items for ranges, but the target area can receive more values + * (e.g. in case of ranges), or less values (e.g. %XTTYPE_HOSTMASK). + * + * %XTTYPE_NONE: option takes no argument + * %XTTYPE_UINT*: standard integer + * %XTTYPE_UINT*RC: colon-separated range of standard integers + * %XTTYPE_DOUBLE: double-precision floating point number + * %XTTYPE_STRING: arbitrary string + * %XTTYPE_TOSMASK: 8-bit TOS value with optional mask + * %XTTYPE_MARKMASK32: 32-bit mark with optional mask + * %XTTYPE_SYSLOGLEVEL: syslog level by name or number + * %XTTYPE_HOST: one host or address (ptr: union nf_inet_addr) + * %XTTYPE_HOSTMASK: one host or address, with an optional prefix length + * (ptr: union nf_inet_addr; only host portion is stored) + * %XTTYPE_PROTOCOL: protocol number/name from /etc/protocols (ptr: uint8_t) + * %XTTYPE_PORT: 16-bit port name or number (supports %XTOPT_NBO) + * %XTTYPE_PORTRC: colon-separated port range (names acceptable), + * (supports %XTOPT_NBO) + * %XTTYPE_PLEN: prefix length + * %XTTYPE_PLENMASK: prefix length (ptr: union nf_inet_addr) + * %XTTYPE_ETHERMAC: Ethernet MAC address in hex form + */ +enum xt_option_type { + XTTYPE_NONE, + XTTYPE_UINT8, + XTTYPE_UINT16, + XTTYPE_UINT32, + XTTYPE_UINT64, + XTTYPE_UINT8RC, + XTTYPE_UINT16RC, + XTTYPE_UINT32RC, + XTTYPE_UINT64RC, + XTTYPE_DOUBLE, + XTTYPE_STRING, + XTTYPE_TOSMASK, + XTTYPE_MARKMASK32, + XTTYPE_SYSLOGLEVEL, + XTTYPE_HOST, + XTTYPE_HOSTMASK, + XTTYPE_PROTOCOL, + XTTYPE_PORT, + XTTYPE_PORTRC, + XTTYPE_PLEN, + XTTYPE_PLENMASK, + XTTYPE_ETHERMAC, +}; + +/** + * %XTOPT_INVERT: option is invertible (usable with !) + * %XTOPT_MAND: option is mandatory + * %XTOPT_MULTI: option may be specified multiple times + * %XTOPT_PUT: store value into memory at @ptroff + * %XTOPT_NBO: store value in network-byte order + * (only certain XTTYPEs recognize this) + */ +enum xt_option_flags { + XTOPT_INVERT = 1 << 0, + XTOPT_MAND = 1 << 1, + XTOPT_MULTI = 1 << 2, + XTOPT_PUT = 1 << 3, + XTOPT_NBO = 1 << 4, +}; + +/** + * @name: name of option + * @type: type of input and validation method, see %XTTYPE_* + * @id: unique number (within extension) for option, 0-31 + * @excl: bitmask of flags that cannot be used with this option + * @also: bitmask of flags that must be used with this option + * @flags: bitmask of option flags, see %XTOPT_* + * @ptroff: offset into private structure for member + * @size: size of the item pointed to by @ptroff; this is a safeguard + * @min: lowest allowed value (for singular integral types) + * @max: highest allowed value (for singular integral types) + */ +struct xt_option_entry { + const char *name; + enum xt_option_type type; + unsigned int id, excl, also, flags; + unsigned int ptroff; + size_t size; + unsigned int min, max; +}; + +/** + * @arg: input from command line + * @ext_name: name of extension currently being processed + * @entry: current option being processed + * @data: per-extension kernel data block + * @xflags: options of the extension that have been used + * @invert: whether option was used with ! + * @nvals: number of results in uXX_multi + * @val: parsed result + * @udata: per-extension private scratch area + * (cf. xtables_{match,target}->udata_size) + */ +struct xt_option_call { + const char *arg, *ext_name; + const struct xt_option_entry *entry; + void *data; + unsigned int xflags; + bool invert; + uint8_t nvals; + union { + uint8_t u8, u8_range[2], syslog_level, protocol; + uint16_t u16, u16_range[2], port, port_range[2]; + uint32_t u32, u32_range[2]; + uint64_t u64, u64_range[2]; + double dbl; + struct { + union nf_inet_addr haddr, hmask; + uint8_t hlen; + }; + struct { + uint8_t tos_value, tos_mask; + }; + struct { + uint32_t mark, mask; + }; + uint8_t ethermac[6]; + } val; + /* Wished for a world where the ones below were gone: */ + union { + struct xt_entry_match **match; + struct xt_entry_target **target; + }; + void *xt_entry; + void *udata; +}; + +/** + * @ext_name: name of extension currently being processed + * @data: per-extension (kernel) data block + * @udata: per-extension private scratch area + * (cf. xtables_{match,target}->udata_size) + * @xflags: options of the extension that have been used + */ +struct xt_fcheck_call { + const char *ext_name; + void *data, *udata; + unsigned int xflags; +}; + +/** + * A "linear"/linked-list based name<->id map, for files similar to + * /etc/iproute2/. + */ +struct xtables_lmap { + char *name; + int id; + struct xtables_lmap *next; +}; + +enum xtables_ext_flags { + XTABLES_EXT_ALIAS = 1 << 0, +}; + +#if XTABLES_VERSION_CODE >= 12 +struct xt_xlate; + +struct xt_xlate_mt_params { + const void *ip; + const struct xt_entry_match *match; + int numeric; + bool escape_quotes; +}; + +struct xt_xlate_tg_params { + const void *ip; + const struct xt_entry_target *target; + int numeric; + bool escape_quotes; +}; +#endif + +/* Include file for additions: new matches and targets. */ +struct xtables_match +{ + /* + * ABI/API version this module requires. Must be first member, + * as the rest of this struct may be subject to ABI changes. + */ + const char *version; + + struct xtables_match *next; + + const char *name; + const char *real_name; + + /* Revision of match (0 by default). */ + uint8_t revision; + + /* Extension flags */ + uint8_t ext_flags; + + uint16_t family; + + /* Size of match data. */ + size_t size; + + /* Size of match data relevant for userspace comparison purposes */ + size_t userspacesize; + + /* Function which prints out usage message. */ + void (*help)(void); + + /* Initialize the match. */ + void (*init)(struct xt_entry_match *m); + + /* Function which parses command options; returns true if it + ate an option */ + /* entry is struct ipt_entry for example */ + int (*parse)(int c, char **argv, int invert, unsigned int *flags, + const void *entry, + struct xt_entry_match **match); + + /* Final check; exit if not ok. */ + void (*final_check)(unsigned int flags); + + /* Prints out the match iff non-NULL: put space at end */ + /* ip is struct ipt_ip * for example */ + void (*print)(const void *ip, + const struct xt_entry_match *match, int numeric); + + /* Saves the match info in parsable form to stdout. */ + /* ip is struct ipt_ip * for example */ + void (*save)(const void *ip, const struct xt_entry_match *match); + + /* Print match name or alias */ + const char *(*alias)(const struct xt_entry_match *match); + + /* Pointer to list of extra command-line options */ + const struct option *extra_opts; + + /* New parser */ + void (*x6_parse)(struct xt_option_call *); + void (*x6_fcheck)(struct xt_fcheck_call *); + const struct xt_option_entry *x6_options; + +#if XTABLES_VERSION_CODE >= 12 + /* Translate iptables to nft */ + int (*xlate)(struct xt_xlate *xl, + const struct xt_xlate_mt_params *params); +#endif + + /* Size of per-extension instance extra "global" scratch space */ + size_t udata_size; + + /* Ignore these men behind the curtain: */ + void *udata; + unsigned int option_offset; + struct xt_entry_match *m; + unsigned int mflags; + unsigned int loaded; /* simulate loading so options are merged properly */ +}; + +struct xtables_target +{ + /* + * ABI/API version this module requires. Must be first member, + * as the rest of this struct may be subject to ABI changes. + */ + const char *version; + + struct xtables_target *next; + + + const char *name; + + /* Real target behind this, if any. */ + const char *real_name; + + /* Revision of target (0 by default). */ + uint8_t revision; + + /* Extension flags */ + uint8_t ext_flags; + + uint16_t family; + + + /* Size of target data. */ + size_t size; + + /* Size of target data relevant for userspace comparison purposes */ + size_t userspacesize; + + /* Function which prints out usage message. */ + void (*help)(void); + + /* Initialize the target. */ + void (*init)(struct xt_entry_target *t); + + /* Function which parses command options; returns true if it + ate an option */ + /* entry is struct ipt_entry for example */ + int (*parse)(int c, char **argv, int invert, unsigned int *flags, + const void *entry, + struct xt_entry_target **targetinfo); + + /* Final check; exit if not ok. */ + void (*final_check)(unsigned int flags); + + /* Prints out the target iff non-NULL: put space at end */ + void (*print)(const void *ip, + const struct xt_entry_target *target, int numeric); + + /* Saves the targinfo in parsable form to stdout. */ + void (*save)(const void *ip, + const struct xt_entry_target *target); + + /* Print target name or alias */ + const char *(*alias)(const struct xt_entry_target *target); + + /* Pointer to list of extra command-line options */ + const struct option *extra_opts; + + /* New parser */ + void (*x6_parse)(struct xt_option_call *); + void (*x6_fcheck)(struct xt_fcheck_call *); + const struct xt_option_entry *x6_options; + +#if XTABLES_VERSION_CODE >= 12 + /* Translate iptables to nft */ + int (*xlate)(struct xt_xlate *xl, + const struct xt_xlate_tg_params *params); +#endif + + size_t udata_size; + + /* Ignore these men behind the curtain: */ + void *udata; + unsigned int option_offset; + struct xt_entry_target *t; + unsigned int tflags; + unsigned int used; + unsigned int loaded; /* simulate loading so options are merged properly */ +}; + +struct xtables_rule_match { + struct xtables_rule_match *next; + struct xtables_match *match; + /* Multiple matches of the same type: the ones before + the current one are completed from parsing point of view */ + bool completed; +}; + +/** + * struct xtables_pprot - + * + * A few hardcoded protocols for 'all' and in case the user has no + * /etc/protocols. + */ +struct xtables_pprot { + const char *name; + uint8_t num; +}; + +enum xtables_tryload { + XTF_DONT_LOAD, + XTF_DURING_LOAD, + XTF_TRY_LOAD, + XTF_LOAD_MUST_SUCCEED, +}; + +enum xtables_exittype { + OTHER_PROBLEM = 1, + PARAMETER_PROBLEM, + VERSION_PROBLEM, + RESOURCE_PROBLEM, + XTF_ONLY_ONCE, + XTF_NO_INVERT, + XTF_BAD_VALUE, + XTF_ONE_ACTION, +}; + +struct xtables_globals +{ + unsigned int option_offset; + const char *program_name, *program_version; + struct option *orig_opts; + struct option *opts; + void (*exit_err)(enum xtables_exittype status, const char *msg, ...) __attribute__((noreturn, format(printf,2,3))); + int (*compat_rev)(const char *name, uint8_t rev, int opt); +}; + +#define XT_GETOPT_TABLEEND {.name = NULL, .has_arg = false} + +#ifdef __cplusplus +extern "C" { +#endif + +extern const char *xtables_modprobe_program; +extern struct xtables_match *xtables_matches; +extern struct xtables_target *xtables_targets; + +extern void xtables_init(void); +extern void xtables_set_nfproto(uint8_t); +extern void *xtables_calloc(size_t, size_t); +extern void *xtables_malloc(size_t); +extern void *xtables_realloc(void *, size_t); + +extern int xtables_insmod(const char *, const char *, bool); +extern int xtables_load_ko(const char *, bool); +extern int xtables_set_params(struct xtables_globals *xtp); +extern void xtables_free_opts(int reset_offset); +extern struct option *xtables_merge_options(struct option *origopts, + struct option *oldopts, const struct option *newopts, + unsigned int *option_offset); + +extern int xtables_init_all(struct xtables_globals *xtp, uint8_t nfproto); +extern struct xtables_match *xtables_find_match(const char *name, + enum xtables_tryload, struct xtables_rule_match **match); +extern struct xtables_target *xtables_find_target(const char *name, + enum xtables_tryload); +extern int xtables_compatible_revision(const char *name, uint8_t revision, + int opt); + +extern void xtables_rule_matches_free(struct xtables_rule_match **matches); + +/* Your shared library should call one of these. */ +extern void xtables_register_match(struct xtables_match *me); +extern void xtables_register_matches(struct xtables_match *, unsigned int); +extern void xtables_register_target(struct xtables_target *me); +extern void xtables_register_targets(struct xtables_target *, unsigned int); + +extern bool xtables_strtoul(const char *, char **, uintmax_t *, + uintmax_t, uintmax_t); +extern bool xtables_strtoui(const char *, char **, unsigned int *, + unsigned int, unsigned int); +extern int xtables_service_to_port(const char *name, const char *proto); +extern uint16_t xtables_parse_port(const char *port, const char *proto); +extern void +xtables_parse_interface(const char *arg, char *vianame, unsigned char *mask); + +/* this is a special 64bit data type that is 8-byte aligned */ +#define aligned_u64 uint64_t __attribute__((aligned(8))) + +extern struct xtables_globals *xt_params; +#define xtables_error (xt_params->exit_err) + +extern void xtables_param_act(unsigned int, const char *, ...); + +extern const char *xtables_ipaddr_to_numeric(const struct in_addr *); +extern const char *xtables_ipaddr_to_anyname(const struct in_addr *); +extern const char *xtables_ipmask_to_numeric(const struct in_addr *); +extern struct in_addr *xtables_numeric_to_ipaddr(const char *); +extern struct in_addr *xtables_numeric_to_ipmask(const char *); +extern int xtables_ipmask_to_cidr(const struct in_addr *); +extern void xtables_ipparse_any(const char *, struct in_addr **, + struct in_addr *, unsigned int *); +extern void xtables_ipparse_multiple(const char *, struct in_addr **, + struct in_addr **, unsigned int *); + +extern struct in6_addr *xtables_numeric_to_ip6addr(const char *); +extern const char *xtables_ip6addr_to_numeric(const struct in6_addr *); +extern const char *xtables_ip6addr_to_anyname(const struct in6_addr *); +extern const char *xtables_ip6mask_to_numeric(const struct in6_addr *); +extern int xtables_ip6mask_to_cidr(const struct in6_addr *); +extern void xtables_ip6parse_any(const char *, struct in6_addr **, + struct in6_addr *, unsigned int *); +extern void xtables_ip6parse_multiple(const char *, struct in6_addr **, + struct in6_addr **, unsigned int *); + +/** + * Print the specified value to standard output, quoting dangerous + * characters if required. + */ +extern void xtables_save_string(const char *value); + +#define FMT_NUMERIC 0x0001 +#define FMT_NOCOUNTS 0x0002 +#define FMT_KILOMEGAGIGA 0x0004 +#define FMT_OPTIONS 0x0008 +#define FMT_NOTABLE 0x0010 +#define FMT_NOTARGET 0x0020 +#define FMT_VIA 0x0040 +#define FMT_NONEWLINE 0x0080 +#define FMT_LINENUMBERS 0x0100 + +#define FMT_PRINT_RULE (FMT_NOCOUNTS | FMT_OPTIONS | FMT_VIA \ + | FMT_NUMERIC | FMT_NOTABLE) +#define FMT(tab,notab) ((format) & FMT_NOTABLE ? (notab) : (tab)) + +extern void xtables_print_num(uint64_t number, unsigned int format); + +#if defined(ALL_INCLUSIVE) || defined(NO_SHARED_LIBS) +# ifdef _INIT +# undef _init +# define _init _INIT +# endif + extern void init_extensions(void); + extern void init_extensions4(void); + extern void init_extensions6(void); +#else +# define _init __attribute__((constructor)) _INIT +#endif + +extern const struct xtables_pprot xtables_chain_protos[]; +extern uint16_t xtables_parse_protocol(const char *s); + +/* kernel revision handling */ +extern int kernel_version; +extern void get_kernel_version(void); +#define LINUX_VERSION(x,y,z) (0x10000*(x) + 0x100*(y) + z) +#define LINUX_VERSION_MAJOR(x) (((x)>>16) & 0xFF) +#define LINUX_VERSION_MINOR(x) (((x)>> 8) & 0xFF) +#define LINUX_VERSION_PATCH(x) ( (x) & 0xFF) + +/* xtoptions.c */ +extern void xtables_option_metavalidate(const char *, + const struct xt_option_entry *); +extern struct option *xtables_options_xfrm(struct option *, struct option *, + const struct xt_option_entry *, + unsigned int *); +extern void xtables_option_parse(struct xt_option_call *); +extern void xtables_option_tpcall(unsigned int, char **, bool, + struct xtables_target *, void *); +extern void xtables_option_mpcall(unsigned int, char **, bool, + struct xtables_match *, void *); +extern void xtables_option_tfcall(struct xtables_target *); +extern void xtables_option_mfcall(struct xtables_match *); +extern void xtables_options_fcheck(const char *, unsigned int, + const struct xt_option_entry *); + +extern struct xtables_lmap *xtables_lmap_init(const char *); +extern void xtables_lmap_free(struct xtables_lmap *); +extern int xtables_lmap_name2id(const struct xtables_lmap *, const char *); +extern const char *xtables_lmap_id2name(const struct xtables_lmap *, int); + +#ifdef XTABLES_INTERNAL + +/* Shipped modules rely on this... */ + +# ifndef ARRAY_SIZE +# define ARRAY_SIZE(x) (sizeof(x) / sizeof(*(x))) +# endif + +extern void _init(void); + +#endif + +#ifdef __cplusplus +} /* extern "C" */ +#endif + +#endif /* _XTABLES_H */ |