1 /* 2 * (C) 2011 Pablo Neira Ayuso <pablo@netfilter.org> 3 * (C) 2011 Intra2net AG <http://www.intra2net.com> 4 * 5 * This program is free software; you can redistribute it and/or modify 6 * it under the terms of the GNU General Public License version 2 (or any 7 * later at your option) as published by the Free Software Foundation. 8 */ 9 #include <linux/module.h> 10 #include <linux/skbuff.h> 11 12 #include <linux/netfilter/x_tables.h> 13 #include <linux/netfilter/nfnetlink_acct.h> 14 #include <linux/netfilter/xt_nfacct.h> 15 16 MODULE_AUTHOR("Pablo Neira Ayuso <pablo@netfilter.org>"); 17 MODULE_DESCRIPTION("Xtables: match for the extended accounting infrastructure"); 18 MODULE_LICENSE("GPL"); 19 MODULE_ALIAS("ipt_nfacct"); 20 MODULE_ALIAS("ip6t_nfacct"); 21 22 static bool nfacct_mt(const struct sk_buff *skb, struct xt_action_param *par) 23 { 24 int overquota; 25 const struct xt_nfacct_match_info *info = par->targinfo; 26 27 nfnl_acct_update(skb, info->nfacct); 28 29 overquota = nfnl_acct_overquota(xt_net(par), skb, info->nfacct); 30 31 return overquota == NFACCT_UNDERQUOTA ? false : true; 32 } 33 34 static int 35 nfacct_mt_checkentry(const struct xt_mtchk_param *par) 36 { 37 struct xt_nfacct_match_info *info = par->matchinfo; 38 struct nf_acct *nfacct; 39 40 nfacct = nfnl_acct_find_get(par->net, info->name); 41 if (nfacct == NULL) { 42 pr_info("xt_nfacct: accounting object with name `%s' " 43 "does not exists\n", info->name); 44 return -ENOENT; 45 } 46 info->nfacct = nfacct; 47 return 0; 48 } 49 50 static void 51 nfacct_mt_destroy(const struct xt_mtdtor_param *par) 52 { 53 const struct xt_nfacct_match_info *info = par->matchinfo; 54 55 nfnl_acct_put(info->nfacct); 56 } 57 58 static struct xt_match nfacct_mt_reg __read_mostly = { 59 .name = "nfacct", 60 .family = NFPROTO_UNSPEC, 61 .checkentry = nfacct_mt_checkentry, 62 .match = nfacct_mt, 63 .destroy = nfacct_mt_destroy, 64 .matchsize = sizeof(struct xt_nfacct_match_info), 65 .me = THIS_MODULE, 66 }; 67 68 static int __init nfacct_mt_init(void) 69 { 70 return xt_register_match(&nfacct_mt_reg); 71 } 72 73 static void __exit nfacct_mt_exit(void) 74 { 75 xt_unregister_match(&nfacct_mt_reg); 76 } 77 78 module_init(nfacct_mt_init); 79 module_exit(nfacct_mt_exit); 80