net/netfilter/xt_comment.c

   1 /*
   2  * Implements a dummy match to allow attaching comments to rules
   3  *
   4  * 2003-05-13 Brad Fisher (brad@info-link.net)
   5  */
   6
   7 #include <linux/module.h>
   8 #include <linux/skbuff.h>
   9 #include <linux/netfilter/x_tables.h>
  10 #include <linux/netfilter/xt_comment.h>
  11
  12 MODULE_AUTHOR("Brad Fisher <brad@info-link.net>");
  13 MODULE_DESCRIPTION("Xtables: No-op match which can be tagged with a comment");
  14 MODULE_LICENSE("GPL");
  15 MODULE_ALIAS("ipt_comment");
  16 MODULE_ALIAS("ip6t_comment");
  17
  18 static bool
  19 comment_mt(const struct sk_buff *skb, const struct net_device *in,
  20            const struct net_device *out, const struct xt_match *match,
  21            const void *matchinfo, int offset, unsigned int protooff,
  22            bool *hotdrop)
  23 {
  24         /* We always match */
  25         return true;
  26 }
  27
  28 static struct xt_match comment_mt_reg[] __read_mostly = {
  29         {
  30                 .name           = "comment",
  31                 .family         = AF_INET,
  32                 .match          = comment_mt,
  33                 .matchsize      = sizeof(struct xt_comment_info),
  34                 .me             = THIS_MODULE
  35         },
  36         {
  37                 .name           = "comment",
  38                 .family         = AF_INET6,
  39                 .match          = comment_mt,
  40                 .matchsize      = sizeof(struct xt_comment_info),
  41                 .me             = THIS_MODULE
  42         },
  43 };
  44
  45 static int __init comment_mt_init(void)
  46 {
  47         return xt_register_matches(comment_mt_reg, ARRAY_SIZE(comment_mt_reg));
  48 }
  49
  50 static void __exit comment_mt_exit(void)
  51 {
  52         xt_unregister_matches(comment_mt_reg, ARRAY_SIZE(comment_mt_reg));
  53 }
  54
  55 module_init(comment_mt_init);
  56 module_exit(comment_mt_exit);