1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * (C) 2011 Pablo Neira Ayuso <pablo@netfilter.org> 4 * (C) 2011 Intra2net AG <http://www.intra2net.com> 5 */ 6 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 7 8 #include <linux/module.h> 9 #include <linux/skbuff.h> 10 11 #include <linux/netfilter/x_tables.h> 12 #include <linux/netfilter/nfnetlink_acct.h> 13 #include <linux/netfilter/xt_nfacct.h> 14 15 MODULE_AUTHOR("Pablo Neira Ayuso <pablo@netfilter.org>"); 16 MODULE_DESCRIPTION("Xtables: match for the extended accounting infrastructure"); 17 MODULE_LICENSE("GPL"); 18 MODULE_ALIAS("ipt_nfacct"); 19 MODULE_ALIAS("ip6t_nfacct"); 20 21 static bool nfacct_mt(const struct sk_buff *skb, struct xt_action_param *par) 22 { 23 int overquota; 24 const struct xt_nfacct_match_info *info = par->targinfo; 25 26 nfnl_acct_update(skb, info->nfacct); 27 28 overquota = nfnl_acct_overquota(xt_net(par), info->nfacct); 29 30 return overquota == NFACCT_UNDERQUOTA ? false : true; 31 } 32 33 static int 34 nfacct_mt_checkentry(const struct xt_mtchk_param *par) 35 { 36 struct xt_nfacct_match_info *info = par->matchinfo; 37 struct nf_acct *nfacct; 38 39 nfacct = nfnl_acct_find_get(par->net, info->name); 40 if (nfacct == NULL) { 41 pr_info_ratelimited("accounting object `%s' does not exists\n", 42 info->name); 43 return -ENOENT; 44 } 45 info->nfacct = nfacct; 46 return 0; 47 } 48 49 static void 50 nfacct_mt_destroy(const struct xt_mtdtor_param *par) 51 { 52 const struct xt_nfacct_match_info *info = par->matchinfo; 53 54 nfnl_acct_put(info->nfacct); 55 } 56 57 static struct xt_match nfacct_mt_reg __read_mostly = { 58 .name = "nfacct", 59 .family = NFPROTO_UNSPEC, 60 .checkentry = nfacct_mt_checkentry, 61 .match = nfacct_mt, 62 .destroy = nfacct_mt_destroy, 63 .matchsize = sizeof(struct xt_nfacct_match_info), 64 .usersize = offsetof(struct xt_nfacct_match_info, nfacct), 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