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/init.h>
  21#include <linux/ip.h>
  22#include <linux/skbuff.h>
  23#include <uapi/linux/netfilter_ipv4/ip_tables.h>
  24
  25int ipt_register_table(struct net *net, const struct xt_table *table,
  26                       const struct ipt_replace *repl,
  27                       const struct nf_hook_ops *ops);
  28
  29void ipt_unregister_table_pre_exit(struct net *net, const char *name);
  30void ipt_unregister_table_exit(struct net *net, const char *name);
  31
  32/* Standard entry. */
  33struct ipt_standard {
  34        struct ipt_entry entry;
  35        struct xt_standard_target target;
  36};
  37
  38struct ipt_error {
  39        struct ipt_entry entry;
  40        struct xt_error_target target;
  41};
  42
  43#define IPT_ENTRY_INIT(__size)                                                 \
  44{                                                                              \
  45        .target_offset  = sizeof(struct ipt_entry),                            \
  46        .next_offset    = (__size),                                            \
  47}
  48
  49#define IPT_STANDARD_INIT(__verdict)                                           \
  50{                                                                              \
  51        .entry          = IPT_ENTRY_INIT(sizeof(struct ipt_standard)),         \
  52        .target         = XT_TARGET_INIT(XT_STANDARD_TARGET,                   \
  53                                         sizeof(struct xt_standard_target)),   \
  54        .target.verdict = -(__verdict) - 1,                                    \
  55}
  56
  57#define IPT_ERROR_INIT                                                         \
  58{                                                                              \
  59        .entry          = IPT_ENTRY_INIT(sizeof(struct ipt_error)),            \
  60        .target         = XT_TARGET_INIT(XT_ERROR_TARGET,                      \
  61                                         sizeof(struct xt_error_target)),      \
  62        .target.errorname = "ERROR",                                           \
  63}
  64
  65extern void *ipt_alloc_initial_table(const struct xt_table *);
  66extern unsigned int ipt_do_table(struct sk_buff *skb,
  67                                 const struct nf_hook_state *state,
  68                                 struct xt_table *table);
  69
  70#ifdef CONFIG_NETFILTER_XTABLES_COMPAT
  71#include <net/compat.h>
  72
  73struct compat_ipt_entry {
  74        struct ipt_ip ip;
  75        compat_uint_t nfcache;
  76        __u16 target_offset;
  77        __u16 next_offset;
  78        compat_uint_t comefrom;
  79        struct compat_xt_counters counters;
  80        unsigned char elems[];
  81};
  82
  83/* Helper functions */
  84static inline struct xt_entry_target *
  85compat_ipt_get_target(struct compat_ipt_entry *e)
  86{
  87        return (void *)e + e->target_offset;
  88}
  89
  90#endif /* CONFIG_COMPAT */
  91#endif /* _IPTABLES_H */
  92