include/uapi/linux/netfilter/x_tables.h

Source file repositories/reference/linux-study-clean/include/uapi/linux/netfilter/x_tables.h

File Facts

System
Linux kernel
Corpus path
include/uapi/linux/netfilter/x_tables.h
Extension
.h
Size
4523 bytes
Lines
189
Domain
Core OS
Bucket
Core Kernel Interface
Inferred role
Core OS: implementation source
Status
source implementation candidate

Why This File Exists

Core operating-system implementation surface: boot, tasks, memory, VFS, syscall-facing interfaces, synchronization, credentials, and isolation.

Dependency Surface

Detected Declarations

Annotated Snippet

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[];
};

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;
};

struct xt_error_target {
	struct xt_entry_target target;
	char errorname[XT_FUNCTION_MAXNAMELEN];
};

/* 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))

Annotation

Implementation Notes