linux/include/uapi/linux/netfilter_ipv4.h

/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
/* IPv4-specific defines for netfilter. 
 * (C)1998 Rusty Russell -- This code is GPL.
 */
#ifndef _UAPI__LINUX_IP_NETFILTER_H
#define _UAPI__LINUX_IP_NETFILTER_H


#include <linux/netfilter.h>

/* only for userspace compatibility */
#ifndef __KERNEL__

#include <limits.h> /* for INT_MIN, INT_MAX */

/* IP Hooks */
/* After promisc drops, checksum checks. */
#define NF_IP_PRE_ROUTING …
/* If the packet is destined for this box. */
#define NF_IP_LOCAL_IN …
/* If the packet is destined for another interface. */
#define NF_IP_FORWARD …
/* Packets coming from a local process. */
#define NF_IP_LOCAL_OUT …
/* Packets about to hit the wire. */
#define NF_IP_POST_ROUTING …
#define NF_IP_NUMHOOKS …
#endif /* ! __KERNEL__ */

enum nf_ip_hook_priorities { … };

/* Arguments for setsockopt SOL_IP: */
/* 2.0 firewalling went from 64 through 71 (and +256, +512, etc). */
/* 2.2 firewalling (+ masq) went from 64 through 76 */
/* 2.4 firewalling went 64 through 67. */
#define SO_ORIGINAL_DST …


#endif /* _UAPI__LINUX_IP_NETFILTER_H */