net/netfilter/xt_NFLOG.c

   1 /*
   2  * Copyright (c) 2006 Patrick McHardy <kaber@trash.net>
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License version 2 as
   6  * published by the Free Software Foundation.
   7  */
   8
   9 #include <linux/module.h>
  10 #include <linux/init.h>
  11 #include <linux/skbuff.h>
  12
  13 #include <linux/netfilter/x_tables.h>
  14 #include <linux/netfilter/xt_NFLOG.h>
  15 #include <net/netfilter/nf_log.h>
  16
  17 MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
  18 MODULE_DESCRIPTION("Xtables: packet logging to netlink using NFLOG");
  19 MODULE_LICENSE("GPL");
  20 MODULE_ALIAS("ipt_NFLOG");
  21 MODULE_ALIAS("ip6t_NFLOG");
  22
  23 static unsigned int
  24 nflog_tg(struct sk_buff *skb, const struct net_device *in,
  25          const struct net_device *out, unsigned int hooknum,
  26          const struct xt_target *target, const void *targinfo)
  27 {
  28         const struct xt_nflog_info *info = targinfo;
  29         struct nf_loginfo li;
  30
  31         li.type              = NF_LOG_TYPE_ULOG;
  32         li.u.ulog.copy_len   = info->len;
  33         li.u.ulog.group      = info->group;
  34         li.u.ulog.qthreshold = info->threshold;
  35
  36         nf_log_packet(target->family, hooknum, skb, in, out, &li,
  37                       "%s", info->prefix);
  38         return XT_CONTINUE;
  39 }
  40
  41 static bool
  42 nflog_tg_check(const char *tablename, const void *entry,
  43                const struct xt_target *target, void *targetinfo,
  44                unsigned int hookmask)
  45 {
  46         const struct xt_nflog_info *info = targetinfo;
  47
  48         if (info->flags & ~XT_NFLOG_MASK)
  49                 return false;
  50         if (info->prefix[sizeof(info->prefix) - 1] != '\0')
  51                 return false;
  52         return true;
  53 }
  54
  55 static struct xt_target nflog_tg_reg[] __read_mostly = {
  56         {
  57                 .name           = "NFLOG",
  58                 .family         = AF_INET,
  59                 .checkentry     = nflog_tg_check,
  60                 .target         = nflog_tg,
  61                 .targetsize     = sizeof(struct xt_nflog_info),
  62                 .me             = THIS_MODULE,
  63         },
  64         {
  65                 .name           = "NFLOG",
  66                 .family         = AF_INET6,
  67                 .checkentry     = nflog_tg_check,
  68                 .target         = nflog_tg,
  69                 .targetsize     = sizeof(struct xt_nflog_info),
  70                 .me             = THIS_MODULE,
  71         },
  72 };
  73
  74 static int __init nflog_tg_init(void)
  75 {
  76         return xt_register_targets(nflog_tg_reg, ARRAY_SIZE(nflog_tg_reg));
  77 }
  78
  79 static void __exit nflog_tg_exit(void)
  80 {
  81         xt_unregister_targets(nflog_tg_reg, ARRAY_SIZE(nflog_tg_reg));
  82 }
  83
  84 module_init(nflog_tg_init);
  85 module_exit(nflog_tg_exit);