include: cache netfilter_arp kernel headers

To ensure that compilation does not break if Linux kernel
headers are not installed in the system.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
diff --git a/include/linux/netfilter_arp.h b/include/linux/netfilter_arp.h
new file mode 100644
index 0000000..92bc6dd
--- /dev/null
+++ b/include/linux/netfilter_arp.h
@@ -0,0 +1,19 @@
+#ifndef __LINUX_ARP_NETFILTER_H
+#define __LINUX_ARP_NETFILTER_H
+
+/* ARP-specific defines for netfilter.
+ * (C)2002 Rusty Russell IBM -- This code is GPL.
+ */
+
+#include <linux/netfilter.h>
+
+/* There is no PF_ARP. */
+#define NF_ARP		0
+
+/* ARP Hooks */
+#define NF_ARP_IN	0
+#define NF_ARP_OUT	1
+#define NF_ARP_FORWARD	2
+#define NF_ARP_NUMHOOKS	3
+
+#endif /* __LINUX_ARP_NETFILTER_H */
diff --git a/include/linux/netfilter_arp/arp_tables.h b/include/linux/netfilter_arp/arp_tables.h
new file mode 100644
index 0000000..bb1ec64
--- /dev/null
+++ b/include/linux/netfilter_arp/arp_tables.h
@@ -0,0 +1,204 @@
+/*
+ * 	Format of an ARP firewall descriptor
+ *
+ * 	src, tgt, src_mask, tgt_mask, arpop, arpop_mask are always stored in
+ *	network byte order.
+ * 	flags are stored in host byte order (of course).
+ */
+
+#ifndef _ARPTABLES_H
+#define _ARPTABLES_H
+
+#include <linux/types.h>
+
+#include <linux/netfilter_arp.h>
+
+#include <linux/netfilter/x_tables.h>
+
+#define ARPT_FUNCTION_MAXNAMELEN XT_FUNCTION_MAXNAMELEN
+#define ARPT_TABLE_MAXNAMELEN XT_TABLE_MAXNAMELEN
+#define arpt_entry_target xt_entry_target
+#define arpt_standard_target xt_standard_target
+#define arpt_error_target xt_error_target
+#define ARPT_CONTINUE XT_CONTINUE
+#define ARPT_RETURN XT_RETURN
+#define arpt_counters_info xt_counters_info
+#define arpt_counters xt_counters
+#define ARPT_STANDARD_TARGET XT_STANDARD_TARGET
+#define ARPT_ERROR_TARGET XT_ERROR_TARGET
+#define ARPT_ENTRY_ITERATE(entries, size, fn, args...) \
+	XT_ENTRY_ITERATE(struct arpt_entry, entries, size, fn, ## args)
+
+#define ARPT_DEV_ADDR_LEN_MAX 16
+
+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[0];
+};
+
+/*
+ * 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
+
+#define ARPT_SO_GET_INFO		(ARPT_BASE_CTL)
+#define ARPT_SO_GET_ENTRIES		(ARPT_BASE_CTL + 1)
+/* #define ARPT_SO_GET_REVISION_MATCH	(APRT_BASE_CTL + 2) */
+#define ARPT_SO_GET_REVISION_TARGET	(ARPT_BASE_CTL + 3)
+#define ARPT_SO_GET_MAX			(ARPT_SO_GET_REVISION_TARGET)
+
+/* The argument to ARPT_SO_GET_INFO */
+struct arpt_getinfo {
+	/* Which table: caller fills this in. */
+	char name[XT_TABLE_MAXNAMELEN];
+
+	/* Kernel fills these in. */
+	/* Which hook entry points are valid: bitmask */
+	unsigned int valid_hooks;
+
+	/* Hook entry points: one per netfilter hook. */
+	unsigned int hook_entry[NF_ARP_NUMHOOKS];
+
+	/* Underflow points. */
+	unsigned int underflow[NF_ARP_NUMHOOKS];
+
+	/* Number of entries */
+	unsigned int num_entries;
+
+	/* Size of entries. */
+	unsigned int size;
+};
+
+/* The argument to ARPT_SO_SET_REPLACE. */
+struct arpt_replace {
+	/* Which table. */
+	char name[XT_TABLE_MAXNAMELEN];
+
+	/* Which hook entry points are valid: bitmask.  You can't
+           change this. */
+	unsigned int valid_hooks;
+
+	/* Number of entries */
+	unsigned int num_entries;
+
+	/* Total size of new entries */
+	unsigned int size;
+
+	/* Hook entry points. */
+	unsigned int hook_entry[NF_ARP_NUMHOOKS];
+
+	/* Underflow points. */
+	unsigned int underflow[NF_ARP_NUMHOOKS];
+
+	/* Information about old entries: */
+	/* Number of counters (must be equal to current number of entries). */
+	unsigned int num_counters;
+	/* The old entries' counters. */
+	struct xt_counters *counters;
+
+	/* The entries (hang off end: not really an array). */
+	struct arpt_entry entries[0];
+};
+
+/* The argument to ARPT_SO_GET_ENTRIES. */
+struct arpt_get_entries {
+	/* Which table: user fills this in. */
+	char name[XT_TABLE_MAXNAMELEN];
+
+	/* User fills this in: total entry size. */
+	unsigned int size;
+
+	/* The entries. */
+	struct arpt_entry entrytable[0];
+};
+
+/* Helper functions */
+static __inline__ struct xt_entry_target *arpt_get_target(struct arpt_entry *e)
+{
+	return (void *)e + e->target_offset;
+}
+
+/*
+ *	Main firewall chains definitions and global var's definitions.
+ */
+#endif /* _ARPTABLES_H */
diff --git a/include/linux/netfilter_arp/arpt_mangle.h b/include/linux/netfilter_arp/arpt_mangle.h
new file mode 100644
index 0000000..250f502
--- /dev/null
+++ b/include/linux/netfilter_arp/arpt_mangle.h
@@ -0,0 +1,26 @@
+#ifndef _ARPT_MANGLE_H
+#define _ARPT_MANGLE_H
+#include <linux/netfilter_arp/arp_tables.h>
+
+#define ARPT_MANGLE_ADDR_LEN_MAX sizeof(struct in_addr)
+struct arpt_mangle
+{
+	char src_devaddr[ARPT_DEV_ADDR_LEN_MAX];
+	char tgt_devaddr[ARPT_DEV_ADDR_LEN_MAX];
+	union {
+		struct in_addr src_ip;
+	} u_s;
+	union {
+		struct in_addr tgt_ip;
+	} u_t;
+	u_int8_t flags;
+	int target;
+};
+
+#define ARPT_MANGLE_SDEV 0x01
+#define ARPT_MANGLE_TDEV 0x02
+#define ARPT_MANGLE_SIP 0x04
+#define ARPT_MANGLE_TIP 0x08
+#define ARPT_MANGLE_MASK 0x0f
+
+#endif /* _ARPT_MANGLE_H */