include/uapi/linux/netfilter_arp/arp_tables.h

Source file repositories/reference/linux-study-clean/include/uapi/linux/netfilter_arp/arp_tables.h

File Facts

System
Linux kernel
Corpus path
include/uapi/linux/netfilter_arp/arp_tables.h
Extension
.h
Size
6099 bytes
Lines
209
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 arpt_devaddr_info {
	char addr[ARPT_DEV_ADDR_LEN_MAX];
	char mask[ARPT_DEV_ADDR_LEN_MAX];
};

/* Yes, Virginia, you have to zero the padding. */
struct arpt_arp {
	/* Source and target IP addr */
	struct in_addr src, tgt;
	/* Mask for src and target IP addr */
	struct in_addr smsk, tmsk;

	/* Device hw address length, src+target device addresses */
	__u8 arhln, arhln_mask;
	struct arpt_devaddr_info src_devaddr;
	struct arpt_devaddr_info tgt_devaddr;

	/* ARP operation code. */
	__be16 arpop, arpop_mask;

	/* ARP hardware address and protocol address format. */
	__be16 arhrd, arhrd_mask;
	__be16 arpro, arpro_mask;

	/* The protocol address length is only accepted if it is 4
	 * so there is no use in offering a way to do filtering on it.
	 */

	char iniface[IFNAMSIZ], outiface[IFNAMSIZ];
	unsigned char iniface_mask[IFNAMSIZ], outiface_mask[IFNAMSIZ];

	/* Flags word */
	__u8 flags;
	/* Inverse flags */
	__u16 invflags;
};

/* Values for "flag" field in struct arpt_ip (general arp structure).
 * No flags defined yet.
 */
#define ARPT_F_MASK		0x00	/* All possible flag bits mask. */

/* Values for "inv" field in struct arpt_arp. */
#define ARPT_INV_VIA_IN		0x0001	/* Invert the sense of IN IFACE. */
#define ARPT_INV_VIA_OUT	0x0002	/* Invert the sense of OUT IFACE */
#define ARPT_INV_SRCIP		0x0004	/* Invert the sense of SRC IP. */
#define ARPT_INV_TGTIP		0x0008	/* Invert the sense of TGT IP. */
#define ARPT_INV_SRCDEVADDR	0x0010	/* Invert the sense of SRC DEV ADDR. */
#define ARPT_INV_TGTDEVADDR	0x0020	/* Invert the sense of TGT DEV ADDR. */
#define ARPT_INV_ARPOP		0x0040	/* Invert the sense of ARP OP. */
#define ARPT_INV_ARPHRD		0x0080	/* Invert the sense of ARP HRD. */
#define ARPT_INV_ARPPRO		0x0100	/* Invert the sense of ARP PRO. */
#define ARPT_INV_ARPHLN		0x0200	/* Invert the sense of ARP HLN. */
#define ARPT_INV_MASK		0x03FF	/* All possible flag bits mask. */

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

	/* Size of arpt_entry + matches */
	__u16 target_offset;
	/* Size of arpt_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 ARPT_BASE_CTL		96

#define ARPT_SO_SET_REPLACE		(ARPT_BASE_CTL)
#define ARPT_SO_SET_ADD_COUNTERS	(ARPT_BASE_CTL + 1)
#define ARPT_SO_SET_MAX			ARPT_SO_SET_ADD_COUNTERS

Annotation

Implementation Notes