LXR linux/include/linux/netfilter_ipv4/ip

   1/* SPDX-License-Identifier: GPL-2.0 */
   2/*
   3 * 25-Jul-1998 Major changes to allow for ip chain table
   4 *
   5 * 3-Jan-2000 Named tables to allow packet selection for different uses.
   6 */
   7
   8/*
   9 *      Format of an IP firewall descriptor
  10 *
  11 *      src, dst, src_mask, dst_mask are always stored in network byte order.
  12 *      flags are stored in host byte order (of course).
  13 *      Port numbers are stored in HOST byte order.
  14 */
  15#ifndef _IPTABLES_H
  16#define _IPTABLES_H
  17
  18#include <linux/if.h>
  19#include <linux/in.h>
  20#include <linux/ip.h>
  21#include <linux/skbuff.h>
  22
  23#include <linux/init.h>
  24#include <uapi/linux/netfilter_ipv4/ip_tables.h>
  25
  26extern void ipt_init(void) __init;
  27
  28int ipt_register_table(struct net *net, const struct xt_table *table,
  29                       const struct ipt_replace *repl,
  30                       const struct nf_hook_ops *ops, struct xt_table **res);
  31void ipt_unregister_table(struct net *net, struct xt_table *table,
  32                          const struct nf_hook_ops *ops);
  33
  34/* Standard entry. */
  35struct ipt_standard {
  36        struct ipt_entry entry;
  37        struct xt_standard_target target;
  38};
  39
  40struct ipt_error {
  41        struct ipt_entry entry;
  42        struct xt_error_target target;
  43};
  44
  45#define IPT_ENTRY_INIT(__size)                                                 \
  46{                                                                              \
  47        .target_offset  = sizeof(struct ipt_entry),                            \
  48        .next_offset    = (__size),                                            \
  49}
  50
  51#define IPT_STANDARD_INIT(__verdict)                                           \
  52{                                                                              \
  53        .entry          = IPT_ENTRY_INIT(sizeof(struct ipt_standard)),         \
  54        .target         = XT_TARGET_INIT(XT_STANDARD_TARGET,                   \
  55                                         sizeof(struct xt_standard_target)),   \
  56        .target.verdict = -(__verdict) - 1,                                    \
  57}
  58
  59#define IPT_ERROR_INIT                                                         \
  60{                                                                              \
  61        .entry          = IPT_ENTRY_INIT(sizeof(struct ipt_error)),            \
  62        .target         = XT_TARGET_INIT(XT_ERROR_TARGET,                      \
  63                                         sizeof(struct xt_error_target)),      \
  64        .target.errorname = "ERROR",                                           \
  65}
  66
  67extern void *ipt_alloc_initial_table(const struct xt_table *);
  68extern unsigned int ipt_do_table(struct sk_buff *skb,
  69                                 const struct nf_hook_state *state,
  70                                 struct xt_table *table);
  71
  72#ifdef CONFIG_COMPAT
  73#include <net/compat.h>
  74
  75struct compat_ipt_entry {
  76        struct ipt_ip ip;
  77        compat_uint_t nfcache;
  78        __u16 target_offset;
  79        __u16 next_offset;
  80        compat_uint_t comefrom;
  81        struct compat_xt_counters counters;
  82        unsigned char elems[0];
  83};
  84
  85/* Helper functions */
  86static inline struct xt_entry_target *
  87compat_ipt_get_target(struct compat_ipt_entry *e)
  88{
  89        return (void *)e + e->target_offset;
  90}
  91
  92#endif /* CONFIG_COMPAT */
  93#endif /* _IPTABLES_H */
  94