include/linux/netfilter_ipv4/ip_tables.h

   1 /*
   2  * 25-Jul-1998 Major changes to allow for ip chain table
   3  *
   4  * 3-Jan-2000 Named tables to allow packet selection for different uses.
   5  */
   6
   7 /*
   8  *      Format of an IP firewall descriptor
   9  *
  10  *      src, dst, src_mask, dst_mask are always stored in network byte order.
  11  *      flags are stored in host byte order (of course).
  12  *      Port numbers are stored in HOST byte order.
  13  */
  14 #ifndef _IPTABLES_H
  15 #define _IPTABLES_H
  16
  17 #include <linux/if.h>
  18 #include <linux/in.h>
  19 #include <linux/ip.h>
  20 #include <linux/skbuff.h>
  21
  22 #include <linux/init.h>
  23 #include <uapi/linux/netfilter_ipv4/ip_tables.h>
  24
  25 extern void ipt_init(void) __init;
  26
  27 extern struct xt_table *ipt_register_table(struct net *net,
  28                                            const struct xt_table *table,
  29                                            const struct ipt_replace *repl);
  30 extern void ipt_unregister_table(struct net *net, struct xt_table *table);
  31
  32 /* Standard entry. */
  33 struct ipt_standard {
  34         struct ipt_entry entry;
  35         struct xt_standard_target target;
  36 };
  37
  38 struct 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
  65 extern void *ipt_alloc_initial_table(const struct xt_table *);
  66 extern unsigned int ipt_do_table(struct sk_buff *skb,
  67                                  unsigned int hook,
  68                                  const struct net_device *in,
  69                                  const struct net_device *out,
  70                                  struct xt_table *table);
  71
  72 #ifdef CONFIG_COMPAT
  73 #include <net/compat.h>
  74
  75 struct 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 */
  86 static inline struct xt_entry_target *
  87 compat_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 */