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 xt_target_param *par)
  25 {
  26         const struct xt_nflog_info *info = par->targinfo;
  27         struct nf_loginfo li;
  28
  29         li.type              = NF_LOG_TYPE_ULOG;
  30         li.u.ulog.copy_len   = info->len;
  31         li.u.ulog.group      = info->group;
  32         li.u.ulog.qthreshold = info->threshold;
  33
  34         nf_log_packet(par->target->family, par->hooknum, skb, par->in,
  35                       par->out, &li, "%s", info->prefix);
  36         return XT_CONTINUE;
  37 }
  38
  39 static bool
  40 nflog_tg_check(const char *tablename, const void *entry,
  41                const struct xt_target *target, void *targetinfo,
  42                unsigned int hookmask)
  43 {
  44         const struct xt_nflog_info *info = targetinfo;
  45
  46         if (info->flags & ~XT_NFLOG_MASK)
  47                 return false;
  48         if (info->prefix[sizeof(info->prefix) - 1] != '\0')
  49                 return false;
  50         return true;
  51 }
  52
  53 static struct xt_target nflog_tg_reg[] __read_mostly = {
  54         {
  55                 .name           = "NFLOG",
  56                 .family         = NFPROTO_IPV4,
  57                 .checkentry     = nflog_tg_check,
  58                 .target         = nflog_tg,
  59                 .targetsize     = sizeof(struct xt_nflog_info),
  60                 .me             = THIS_MODULE,
  61         },
  62         {
  63                 .name           = "NFLOG",
  64                 .family         = NFPROTO_IPV6,
  65                 .checkentry     = nflog_tg_check,
  66                 .target         = nflog_tg,
  67                 .targetsize     = sizeof(struct xt_nflog_info),
  68                 .me             = THIS_MODULE,
  69         },
  70 };
  71
  72 static int __init nflog_tg_init(void)
  73 {
  74         return xt_register_targets(nflog_tg_reg, ARRAY_SIZE(nflog_tg_reg));
  75 }
  76
  77 static void __exit nflog_tg_exit(void)
  78 {
  79         xt_unregister_targets(nflog_tg_reg, ARRAY_SIZE(nflog_tg_reg));
  80 }
  81
  82 module_init(nflog_tg_init);
  83 module_exit(nflog_tg_exit);