include/uapi/linux/netfilter_ipv4/ip_tables.h

Source file repositories/reference/linux-study-clean/include/uapi/linux/netfilter_ipv4/ip_tables.h

File Facts

System
Linux kernel
Corpus path
include/uapi/linux/netfilter_ipv4/ip_tables.h
Extension
.h
Size
6747 bytes
Lines
232
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 ipt_ip {
	/* Source and destination IP addr */
	struct in_addr src, dst;
	/* Mask for src and dest IP addr */
	struct in_addr smsk, dmsk;
	char iniface[IFNAMSIZ], outiface[IFNAMSIZ];
	unsigned char iniface_mask[IFNAMSIZ], outiface_mask[IFNAMSIZ];

	/* Protocol, 0 = ANY */
	__u16 proto;

	/* Flags word */
	__u8 flags;
	/* Inverse flags */
	__u8 invflags;
};

/* Values for "flag" field in struct ipt_ip (general ip structure). */
#define IPT_F_FRAG		0x01	/* Set if rule is a fragment rule */
#define IPT_F_GOTO		0x02	/* Set if jump is a goto */
#define IPT_F_MASK		0x03	/* All possible flag bits mask. */

/* Values for "inv" field in struct ipt_ip. */
#define IPT_INV_VIA_IN		0x01	/* Invert the sense of IN IFACE. */
#define IPT_INV_VIA_OUT		0x02	/* Invert the sense of OUT IFACE */
#define IPT_INV_TOS		0x04	/* Invert the sense of TOS. */
#define IPT_INV_SRCIP		0x08	/* Invert the sense of SRC IP. */
#define IPT_INV_DSTIP		0x10	/* Invert the sense of DST OP. */
#define IPT_INV_FRAG		0x20	/* Invert the sense of FRAG. */
#define IPT_INV_PROTO		XT_INV_PROTO
#define IPT_INV_MASK		0x7F	/* All possible flag bits mask. */

/* This structure defines each of the firewall rules.  Consists of 3
   parts which are 1) general IP header stuff 2) match specific
   stuff 3) the target to perform if the rule matches */
struct ipt_entry {
	struct ipt_ip ip;

	/* Mark with fields that we care about. */
	unsigned int nfcache;

	/* Size of ipt_entry + matches */
	__u16 target_offset;
	/* Size of ipt_entry + matches + target */
	__u16 next_offset;

	/* Back pointer */
	unsigned int comefrom;

	/* Packet and byte counters. */
	struct xt_counters counters;

	/* The matches (if any), then the target. */
	unsigned char elems[];
};

/*
 * New IP firewall options for [gs]etsockopt at the RAW IP level.
 * Unlike BSD Linux inherits IP options so you don't have to use a raw
 * socket for this. Instead we check rights in the calls.
 *
 * ATTENTION: check linux/in.h before adding new number here.
 */
#define IPT_BASE_CTL		64

#define IPT_SO_SET_REPLACE	(IPT_BASE_CTL)
#define IPT_SO_SET_ADD_COUNTERS	(IPT_BASE_CTL + 1)
#define IPT_SO_SET_MAX		IPT_SO_SET_ADD_COUNTERS

#define IPT_SO_GET_INFO			(IPT_BASE_CTL)
#define IPT_SO_GET_ENTRIES		(IPT_BASE_CTL + 1)
#define IPT_SO_GET_REVISION_MATCH	(IPT_BASE_CTL + 2)
#define IPT_SO_GET_REVISION_TARGET	(IPT_BASE_CTL + 3)
#define IPT_SO_GET_MAX			IPT_SO_GET_REVISION_TARGET

/* ICMP matching stuff */
struct ipt_icmp {
	__u8 type;				/* type to match */
	__u8 code[2];				/* range of code */
	__u8 invflags;				/* Inverse flags */
};

/* Values for "inv" field for struct ipt_icmp. */
#define IPT_ICMP_INV	0x01	/* Invert the sense of type/code test */

/* The argument to IPT_SO_GET_INFO */
struct ipt_getinfo {
	/* Which table: caller fills this in. */
	char name[XT_TABLE_MAXNAMELEN];

Annotation

Implementation Notes