| #ifndef _X_TABLES_H |
| #define _X_TABLES_H |
| #include <linux/kernel.h> |
| #include <linux/types.h> |
| |
| #define XT_FUNCTION_MAXNAMELEN 30 |
| #define XT_EXTENSION_MAXNAMELEN 29 |
| #define XT_TABLE_MAXNAMELEN 32 |
| |
| struct xt_entry_match { |
| union { |
| struct { |
| __u16 match_size; |
| |
| /* Used by userspace */ |
| char name[XT_EXTENSION_MAXNAMELEN]; |
| __u8 revision; |
| } user; |
| struct { |
| __u16 match_size; |
| |
| /* Used inside the kernel */ |
| struct xt_match *match; |
| } kernel; |
| |
| /* Total length */ |
| __u16 match_size; |
| } u; |
| |
| unsigned char data[0]; |
| }; |
| |
| struct xt_entry_target { |
| union { |
| struct { |
| __u16 target_size; |
| |
| /* Used by userspace */ |
| char name[XT_EXTENSION_MAXNAMELEN]; |
| __u8 revision; |
| } user; |
| struct { |
| __u16 target_size; |
| |
| /* Used inside the kernel */ |
| struct xt_target *target; |
| } kernel; |
| |
| /* Total length */ |
| __u16 target_size; |
| } u; |
| |
| unsigned char data[0]; |
| }; |
| |
| #define XT_TARGET_INIT(__name, __size) \ |
| { \ |
| .target.u.user = { \ |
| .target_size = XT_ALIGN(__size), \ |
| .name = __name, \ |
| }, \ |
| } |
| |
| struct xt_standard_target { |
| struct xt_entry_target target; |
| int verdict; |
| }; |
| |
| /* The argument to IPT_SO_GET_REVISION_*. Returns highest revision |
| * kernel supports, if >= revision. */ |
| struct xt_get_revision { |
| char name[XT_EXTENSION_MAXNAMELEN]; |
| __u8 revision; |
| }; |
| |
| /* CONTINUE verdict for targets */ |
| #define XT_CONTINUE 0xFFFFFFFF |
| |
| /* For standard target */ |
| #define XT_RETURN (-NF_REPEAT - 1) |
| |
| /* this is a dummy structure to find out the alignment requirement for a struct |
| * containing all the fundamental data types that are used in ipt_entry, |
| * ip6t_entry and arpt_entry. This sucks, and it is a hack. It will be my |
| * personal pleasure to remove it -HW |
| */ |
| struct _xt_align { |
| __u8 u8; |
| __u16 u16; |
| __u32 u32; |
| __u64 u64; |
| }; |
| |
| #define XT_ALIGN(s) __ALIGN_KERNEL((s), __alignof__(struct _xt_align)) |
| |
| /* Standard return verdict, or do jump. */ |
| #define XT_STANDARD_TARGET "" |
| /* Error verdict. */ |
| #define XT_ERROR_TARGET "ERROR" |
| |
| #define SET_COUNTER(c,b,p) do { (c).bcnt = (b); (c).pcnt = (p); } while(0) |
| #define ADD_COUNTER(c,b,p) do { (c).bcnt += (b); (c).pcnt += (p); } while(0) |
| |
| struct xt_counters { |
| __u64 pcnt, bcnt; /* Packet and byte counters */ |
| }; |
| |
| /* The argument to IPT_SO_ADD_COUNTERS. */ |
| struct xt_counters_info { |
| /* Which table. */ |
| char name[XT_TABLE_MAXNAMELEN]; |
| |
| unsigned int num_counters; |
| |
| /* The counters (actually `number' of these). */ |
| struct xt_counters counters[0]; |
| }; |
| |
| #define XT_INV_PROTO 0x40 /* Invert the sense of PROTO. */ |
| |
| #ifndef __KERNEL__ |
| /* fn returns 0 to continue iteration */ |
| #define XT_MATCH_ITERATE(type, e, fn, args...) \ |
| ({ \ |
| unsigned int __i; \ |
| int __ret = 0; \ |
| struct xt_entry_match *__m; \ |
| \ |
| for (__i = sizeof(type); \ |
| __i < (e)->target_offset; \ |
| __i += __m->u.match_size) { \ |
| __m = (void *)e + __i; \ |
| \ |
| __ret = fn(__m , ## args); \ |
| if (__ret != 0) \ |
| break; \ |
| } \ |
| __ret; \ |
| }) |
| |
| /* fn returns 0 to continue iteration */ |
| #define XT_ENTRY_ITERATE_CONTINUE(type, entries, size, n, fn, args...) \ |
| ({ \ |
| unsigned int __i, __n; \ |
| int __ret = 0; \ |
| type *__entry; \ |
| \ |
| for (__i = 0, __n = 0; __i < (size); \ |
| __i += __entry->next_offset, __n++) { \ |
| __entry = (void *)(entries) + __i; \ |
| if (__n < n) \ |
| continue; \ |
| \ |
| __ret = fn(__entry , ## args); \ |
| if (__ret != 0) \ |
| break; \ |
| } \ |
| __ret; \ |
| }) |
| |
| /* fn returns 0 to continue iteration */ |
| #define XT_ENTRY_ITERATE(type, entries, size, fn, args...) \ |
| XT_ENTRY_ITERATE_CONTINUE(type, entries, size, 0, fn, args) |
| |
| #endif /* !__KERNEL__ */ |
| |
| /* pos is normally a struct ipt_entry/ip6t_entry/etc. */ |
| #define xt_entry_foreach(pos, ehead, esize) \ |
| for ((pos) = (typeof(pos))(ehead); \ |
| (pos) < (typeof(pos))((char *)(ehead) + (esize)); \ |
| (pos) = (typeof(pos))((char *)(pos) + (pos)->next_offset)) |
| |
| /* can only be xt_entry_match, so no use of typeof here */ |
| #define xt_ematch_foreach(pos, entry) \ |
| for ((pos) = (struct xt_entry_match *)entry->elems; \ |
| (pos) < (struct xt_entry_match *)((char *)(entry) + \ |
| (entry)->target_offset); \ |
| (pos) = (struct xt_entry_match *)((char *)(pos) + \ |
| (pos)->u.match_size)) |
| |
| #ifdef __KERNEL__ |
| |
| #include <linux/netdevice.h> |
| |
| /** |
| * struct xt_action_param - parameters for matches/targets |
| * |
| * @match: the match extension |
| * @target: the target extension |
| * @matchinfo: per-match data |
| * @targetinfo: per-target data |
| * @in: input netdevice |
| * @out: output netdevice |
| * @fragoff: packet is a fragment, this is the data offset |
| * @thoff: position of transport header relative to skb->data |
| * @hook: hook number given packet came from |
| * @family: Actual NFPROTO_* through which the function is invoked |
| * (helpful when match->family == NFPROTO_UNSPEC) |
| * |
| * Fields written to by extensions: |
| * |
| * @hotdrop: drop packet if we had inspection problems |
| * Network namespace obtainable using dev_net(in/out) |
| */ |
| struct xt_action_param { |
| union { |
| const struct xt_match *match; |
| const struct xt_target *target; |
| }; |
| union { |
| const void *matchinfo, *targinfo; |
| }; |
| const struct net_device *in, *out; |
| int fragoff; |
| unsigned int thoff; |
| unsigned int hooknum; |
| u_int8_t family; |
| bool hotdrop; |
| }; |
| |
| /** |
| * struct xt_mtchk_param - parameters for match extensions' |
| * checkentry functions |
| * |
| * @net: network namespace through which the check was invoked |
| * @table: table the rule is tried to be inserted into |
| * @entryinfo: the family-specific rule data |
| * (struct ipt_ip, ip6t_ip, arpt_arp or (note) ebt_entry) |
| * @match: struct xt_match through which this function was invoked |
| * @matchinfo: per-match data |
| * @hook_mask: via which hooks the new rule is reachable |
| * Other fields as above. |
| */ |
| struct xt_mtchk_param { |
| struct net *net; |
| const char *table; |
| const void *entryinfo; |
| const struct xt_match *match; |
| void *matchinfo; |
| unsigned int hook_mask; |
| u_int8_t family; |
| }; |
| |
| /** |
| * struct xt_mdtor_param - match destructor parameters |
| * Fields as above. |
| */ |
| struct xt_mtdtor_param { |
| struct net *net; |
| const struct xt_match *match; |
| void *matchinfo; |
| u_int8_t family; |
| }; |
| |
| /** |
| * struct xt_tgchk_param - parameters for target extensions' |
| * checkentry functions |
| * |
| * @entryinfo: the family-specific rule data |
| * (struct ipt_entry, ip6t_entry, arpt_entry, ebt_entry) |
| * |
| * Other fields see above. |
| */ |
| struct xt_tgchk_param { |
| struct net *net; |
| const char *table; |
| const void *entryinfo; |
| const struct xt_target *target; |
| void *targinfo; |
| unsigned int hook_mask; |
| u_int8_t family; |
| }; |
| |
| /* Target destructor parameters */ |
| struct xt_tgdtor_param { |
| struct net *net; |
| const struct xt_target *target; |
| void *targinfo; |
| u_int8_t family; |
| }; |
| |
| struct xt_match { |
| struct list_head list; |
| |
| const char name[XT_EXTENSION_MAXNAMELEN]; |
| u_int8_t revision; |
| |
| /* Return true or false: return FALSE and set *hotdrop = 1 to |
| force immediate packet drop. */ |
| /* Arguments changed since 2.6.9, as this must now handle |
| non-linear skb, using skb_header_pointer and |
| skb_ip_make_writable. */ |
| bool (*match)(const struct sk_buff *skb, |
| struct xt_action_param *); |
| |
| /* Called when user tries to insert an entry of this type. */ |
| int (*checkentry)(const struct xt_mtchk_param *); |
| |
| /* Called when entry of this type deleted. */ |
| void (*destroy)(const struct xt_mtdtor_param *); |
| #ifdef CONFIG_COMPAT |
| /* Called when userspace align differs from kernel space one */ |
| void (*compat_from_user)(void *dst, const void *src); |
| int (*compat_to_user)(void __user *dst, const void *src); |
| #endif |
| /* Set this to THIS_MODULE if you are a module, otherwise NULL */ |
| struct module *me; |
| |
| const char *table; |
| unsigned int matchsize; |
| #ifdef CONFIG_COMPAT |
| unsigned int compatsize; |
| #endif |
| unsigned int hooks; |
| unsigned short proto; |
| |
| unsigned short family; |
| }; |
| |
| /* Registration hooks for targets. */ |
| struct xt_target { |
| struct list_head list; |
| |
| const char name[XT_EXTENSION_MAXNAMELEN]; |
| u_int8_t revision; |
| |
| /* Returns verdict. Argument order changed since 2.6.9, as this |
| must now handle non-linear skbs, using skb_copy_bits and |
| skb_ip_make_writable. */ |
| unsigned int (*target)(struct sk_buff *skb, |
| const struct xt_action_param *); |
| |
| /* Called when user tries to insert an entry of this type: |
| hook_mask is a bitmask of hooks from which it can be |
| called. */ |
| /* Should return 0 on success or an error code otherwise (-Exxxx). */ |
| int (*checkentry)(const struct xt_tgchk_param *); |
| |
| /* Called when entry of this type deleted. */ |
| void (*destroy)(const struct xt_tgdtor_param *); |
| #ifdef CONFIG_COMPAT |
| /* Called when userspace align differs from kernel space one */ |
| void (*compat_from_user)(void *dst, const void *src); |
| int (*compat_to_user)(void __user *dst, const void *src); |
| #endif |
| /* Set this to THIS_MODULE if you are a module, otherwise NULL */ |
| struct module *me; |
| |
| const char *table; |
| unsigned int targetsize; |
| #ifdef CONFIG_COMPAT |
| unsigned int compatsize; |
| #endif |
| unsigned int hooks; |
| unsigned short proto; |
| |
| unsigned short family; |
| }; |
| |
| /* Furniture shopping... */ |
| struct xt_table { |
| struct list_head list; |
| |
| /* What hooks you will enter on */ |
| unsigned int valid_hooks; |
| |
| /* Man behind the curtain... */ |
| struct xt_table_info *private; |
| |
| /* Set this to THIS_MODULE if you are a module, otherwise NULL */ |
| struct module *me; |
| |
| u_int8_t af; /* address/protocol family */ |
| int priority; /* hook order */ |
| |
| /* A unique name... */ |
| const char name[XT_TABLE_MAXNAMELEN]; |
| }; |
| |
| #include <linux/netfilter_ipv4.h> |
| |
| /* The table itself */ |
| struct xt_table_info { |
| /* Size per table */ |
| unsigned int size; |
| /* Number of entries: FIXME. --RR */ |
| unsigned int number; |
| /* Initial number of entries. Needed for module usage count */ |
| unsigned int initial_entries; |
| |
| /* Entry points and underflows */ |
| unsigned int hook_entry[NF_INET_NUMHOOKS]; |
| unsigned int underflow[NF_INET_NUMHOOKS]; |
| |
| /* |
| * Number of user chains. Since tables cannot have loops, at most |
| * @stacksize jumps (number of user chains) can possibly be made. |
| */ |
| unsigned int stacksize; |
| unsigned int __percpu *stackptr; |
| void ***jumpstack; |
| /* ipt_entry tables: one per CPU */ |
| /* Note : this field MUST be the last one, see XT_TABLE_INFO_SZ */ |
| void *entries[1]; |
| }; |
| |
| #define XT_TABLE_INFO_SZ (offsetof(struct xt_table_info, entries) \ |
| + nr_cpu_ids * sizeof(char *)) |
| extern int xt_register_target(struct xt_target *target); |
| extern void xt_unregister_target(struct xt_target *target); |
| extern int xt_register_targets(struct xt_target *target, unsigned int n); |
| extern void xt_unregister_targets(struct xt_target *target, unsigned int n); |
| |
| extern int xt_register_match(struct xt_match *target); |
| extern void xt_unregister_match(struct xt_match *target); |
| extern int xt_register_matches(struct xt_match *match, unsigned int n); |
| extern void xt_unregister_matches(struct xt_match *match, unsigned int n); |
| |
| extern int xt_check_match(struct xt_mtchk_param *, |
| unsigned int size, u_int8_t proto, bool inv_proto); |
| extern int xt_check_target(struct xt_tgchk_param *, |
| unsigned int size, u_int8_t proto, bool inv_proto); |
| |
| extern struct xt_table *xt_register_table(struct net *net, |
| const struct xt_table *table, |
| struct xt_table_info *bootstrap, |
| struct xt_table_info *newinfo); |
| extern void *xt_unregister_table(struct xt_table *table); |
| |
| extern struct xt_table_info *xt_replace_table(struct xt_table *table, |
| unsigned int num_counters, |
| struct xt_table_info *newinfo, |
| int *error); |
| |
| extern struct xt_match *xt_find_match(u8 af, const char *name, u8 revision); |
| extern struct xt_target *xt_find_target(u8 af, const char *name, u8 revision); |
| extern struct xt_match *xt_request_find_match(u8 af, const char *name, |
| u8 revision); |
| extern struct xt_target *xt_request_find_target(u8 af, const char *name, |
| u8 revision); |
| extern int xt_find_revision(u8 af, const char *name, u8 revision, |
| int target, int *err); |
| |
| extern struct xt_table *xt_find_table_lock(struct net *net, u_int8_t af, |
| const char *name); |
| extern void xt_table_unlock(struct xt_table *t); |
| |
| extern int xt_proto_init(struct net *net, u_int8_t af); |
| extern void xt_proto_fini(struct net *net, u_int8_t af); |
| |
| extern struct xt_table_info *xt_alloc_table_info(unsigned int size); |
| extern void xt_free_table_info(struct xt_table_info *info); |
| |
| /* |
| * Per-CPU spinlock associated with per-cpu table entries, and |
| * with a counter for the "reading" side that allows a recursive |
| * reader to avoid taking the lock and deadlocking. |
| * |
| * "reading" is used by ip/arp/ip6 tables rule processing which runs per-cpu. |
| * It needs to ensure that the rules are not being changed while the packet |
| * is being processed. In some cases, the read lock will be acquired |
| * twice on the same CPU; this is okay because of the count. |
| * |
| * "writing" is used when reading counters. |
| * During replace any readers that are using the old tables have to complete |
| * before freeing the old table. This is handled by the write locking |
| * necessary for reading the counters. |
| */ |
| struct xt_info_lock { |
| spinlock_t lock; |
| unsigned char readers; |
| }; |
| DECLARE_PER_CPU(struct xt_info_lock, xt_info_locks); |
| |
| /* |
| * Note: we need to ensure that preemption is disabled before acquiring |
| * the per-cpu-variable, so we do it as a two step process rather than |
| * using "spin_lock_bh()". |
| * |
| * We _also_ need to disable bottom half processing before updating our |
| * nesting count, to make sure that the only kind of re-entrancy is this |
| * code being called by itself: since the count+lock is not an atomic |
| * operation, we can allow no races. |
| * |
| * _Only_ that special combination of being per-cpu and never getting |
| * re-entered asynchronously means that the count is safe. |
| */ |
| static inline void xt_info_rdlock_bh(void) |
| { |
| struct xt_info_lock *lock; |
| |
| local_bh_disable(); |
| lock = &__get_cpu_var(xt_info_locks); |
| if (likely(!lock->readers++)) |
| spin_lock(&lock->lock); |
| } |
| |
| static inline void xt_info_rdunlock_bh(void) |
| { |
| struct xt_info_lock *lock = &__get_cpu_var(xt_info_locks); |
| |
| if (likely(!--lock->readers)) |
| spin_unlock(&lock->lock); |
| local_bh_enable(); |
| } |
| |
| /* |
| * The "writer" side needs to get exclusive access to the lock, |
| * regardless of readers. This must be called with bottom half |
| * processing (and thus also preemption) disabled. |
| */ |
| static inline void xt_info_wrlock(unsigned int cpu) |
| { |
| spin_lock(&per_cpu(xt_info_locks, cpu).lock); |
| } |
| |
| static inline void xt_info_wrunlock(unsigned int cpu) |
| { |
| spin_unlock(&per_cpu(xt_info_locks, cpu).lock); |
| } |
| |
| /* |
| * This helper is performance critical and must be inlined |
| */ |
| static inline unsigned long ifname_compare_aligned(const char *_a, |
| const char *_b, |
| const char *_mask) |
| { |
| const unsigned long *a = (const unsigned long *)_a; |
| const unsigned long *b = (const unsigned long *)_b; |
| const unsigned long *mask = (const unsigned long *)_mask; |
| unsigned long ret; |
| |
| ret = (a[0] ^ b[0]) & mask[0]; |
| if (IFNAMSIZ > sizeof(unsigned long)) |
| ret |= (a[1] ^ b[1]) & mask[1]; |
| if (IFNAMSIZ > 2 * sizeof(unsigned long)) |
| ret |= (a[2] ^ b[2]) & mask[2]; |
| if (IFNAMSIZ > 3 * sizeof(unsigned long)) |
| ret |= (a[3] ^ b[3]) & mask[3]; |
| BUILD_BUG_ON(IFNAMSIZ > 4 * sizeof(unsigned long)); |
| return ret; |
| } |
| |
| extern struct nf_hook_ops *xt_hook_link(const struct xt_table *, nf_hookfn *); |
| extern void xt_hook_unlink(const struct xt_table *, struct nf_hook_ops *); |
| |
| #ifdef CONFIG_COMPAT |
| #include <net/compat.h> |
| |
| struct compat_xt_entry_match { |
| union { |
| struct { |
| u_int16_t match_size; |
| char name[XT_FUNCTION_MAXNAMELEN - 1]; |
| u_int8_t revision; |
| } user; |
| struct { |
| u_int16_t match_size; |
| compat_uptr_t match; |
| } kernel; |
| u_int16_t match_size; |
| } u; |
| unsigned char data[0]; |
| }; |
| |
| struct compat_xt_entry_target { |
| union { |
| struct { |
| u_int16_t target_size; |
| char name[XT_FUNCTION_MAXNAMELEN - 1]; |
| u_int8_t revision; |
| } user; |
| struct { |
| u_int16_t target_size; |
| compat_uptr_t target; |
| } kernel; |
| u_int16_t target_size; |
| } u; |
| unsigned char data[0]; |
| }; |
| |
| /* FIXME: this works only on 32 bit tasks |
| * need to change whole approach in order to calculate align as function of |
| * current task alignment */ |
| |
| struct compat_xt_counters { |
| compat_u64 pcnt, bcnt; /* Packet and byte counters */ |
| }; |
| |
| struct compat_xt_counters_info { |
| char name[XT_TABLE_MAXNAMELEN]; |
| compat_uint_t num_counters; |
| struct compat_xt_counters counters[0]; |
| }; |
| |
| struct _compat_xt_align { |
| __u8 u8; |
| __u16 u16; |
| __u32 u32; |
| compat_u64 u64; |
| }; |
| |
| #define COMPAT_XT_ALIGN(s) __ALIGN_KERNEL((s), __alignof__(struct _compat_xt_align)) |
| |
| extern void xt_compat_lock(u_int8_t af); |
| extern void xt_compat_unlock(u_int8_t af); |
| |
| extern int xt_compat_add_offset(u_int8_t af, unsigned int offset, short delta); |
| extern void xt_compat_flush_offsets(u_int8_t af); |
| extern int xt_compat_calc_jump(u_int8_t af, unsigned int offset); |
| |
| extern int xt_compat_match_offset(const struct xt_match *match); |
| extern int xt_compat_match_from_user(struct xt_entry_match *m, |
| void **dstptr, unsigned int *size); |
| extern int xt_compat_match_to_user(const struct xt_entry_match *m, |
| void __user **dstptr, unsigned int *size); |
| |
| extern int xt_compat_target_offset(const struct xt_target *target); |
| extern void xt_compat_target_from_user(struct xt_entry_target *t, |
| void **dstptr, unsigned int *size); |
| extern int xt_compat_target_to_user(const struct xt_entry_target *t, |
| void __user **dstptr, unsigned int *size); |
| |
| #endif /* CONFIG_COMPAT */ |
| #endif /* __KERNEL__ */ |
| |
| #endif /* _X_TABLES_H */ |