| /* |
| * xt_connmark - Netfilter module to operate on connection marks |
| * |
| * Copyright (C) 2002,2004 MARA Systems AB <http://www.marasystems.com> |
| * by Henrik Nordstrom <hno@marasystems.com> |
| * Copyright © CC Computer Consultants GmbH, 2007 - 2008 |
| * Jan Engelhardt <jengelh@medozas.de> |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License as published by |
| * the Free Software Foundation; either version 2 of the License, or |
| * (at your option) any later version. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License |
| * along with this program; if not, write to the Free Software |
| * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| */ |
| |
| #include <linux/module.h> |
| #include <linux/skbuff.h> |
| #include <net/netfilter/nf_conntrack.h> |
| #include <net/netfilter/nf_conntrack_ecache.h> |
| #include <linux/netfilter/x_tables.h> |
| #include <linux/netfilter/xt_connmark.h> |
| |
| MODULE_AUTHOR("Henrik Nordstrom <hno@marasystems.com>"); |
| MODULE_DESCRIPTION("Xtables: connection mark operations"); |
| MODULE_LICENSE("GPL"); |
| MODULE_ALIAS("ipt_CONNMARK"); |
| MODULE_ALIAS("ip6t_CONNMARK"); |
| MODULE_ALIAS("ipt_connmark"); |
| MODULE_ALIAS("ip6t_connmark"); |
| |
| static unsigned int |
| connmark_tg(struct sk_buff *skb, const struct xt_target_param *par) |
| { |
| const struct xt_connmark_tginfo1 *info = par->targinfo; |
| enum ip_conntrack_info ctinfo; |
| struct nf_conn *ct; |
| u_int32_t newmark; |
| |
| ct = nf_ct_get(skb, &ctinfo); |
| if (ct == NULL) |
| return XT_CONTINUE; |
| |
| switch (info->mode) { |
| case XT_CONNMARK_SET: |
| newmark = (ct->mark & ~info->ctmask) ^ info->ctmark; |
| if (ct->mark != newmark) { |
| ct->mark = newmark; |
| nf_conntrack_event_cache(IPCT_MARK, ct); |
| } |
| break; |
| case XT_CONNMARK_SAVE: |
| newmark = (ct->mark & ~info->ctmask) ^ |
| (skb->mark & info->nfmask); |
| if (ct->mark != newmark) { |
| ct->mark = newmark; |
| nf_conntrack_event_cache(IPCT_MARK, ct); |
| } |
| break; |
| case XT_CONNMARK_RESTORE: |
| newmark = (skb->mark & ~info->nfmask) ^ |
| (ct->mark & info->ctmask); |
| skb->mark = newmark; |
| break; |
| } |
| |
| return XT_CONTINUE; |
| } |
| |
| static int connmark_tg_check(const struct xt_tgchk_param *par) |
| { |
| if (nf_ct_l3proto_try_module_get(par->family) < 0) { |
| pr_info("cannot load conntrack support for proto=%u\n", |
| par->family); |
| return false; |
| } |
| return true; |
| } |
| |
| static void connmark_tg_destroy(const struct xt_tgdtor_param *par) |
| { |
| nf_ct_l3proto_module_put(par->family); |
| } |
| |
| static bool |
| connmark_mt(const struct sk_buff *skb, const struct xt_match_param *par) |
| { |
| const struct xt_connmark_mtinfo1 *info = par->matchinfo; |
| enum ip_conntrack_info ctinfo; |
| const struct nf_conn *ct; |
| |
| ct = nf_ct_get(skb, &ctinfo); |
| if (ct == NULL) |
| return false; |
| |
| return ((ct->mark & info->mask) == info->mark) ^ info->invert; |
| } |
| |
| static int connmark_mt_check(const struct xt_mtchk_param *par) |
| { |
| if (nf_ct_l3proto_try_module_get(par->family) < 0) { |
| pr_info("cannot load conntrack support for proto=%u\n", |
| par->family); |
| return false; |
| } |
| return true; |
| } |
| |
| static void connmark_mt_destroy(const struct xt_mtdtor_param *par) |
| { |
| nf_ct_l3proto_module_put(par->family); |
| } |
| |
| static struct xt_target connmark_tg_reg __read_mostly = { |
| .name = "CONNMARK", |
| .revision = 1, |
| .family = NFPROTO_UNSPEC, |
| .checkentry = connmark_tg_check, |
| .target = connmark_tg, |
| .targetsize = sizeof(struct xt_connmark_tginfo1), |
| .destroy = connmark_tg_destroy, |
| .me = THIS_MODULE, |
| }; |
| |
| static struct xt_match connmark_mt_reg __read_mostly = { |
| .name = "connmark", |
| .revision = 1, |
| .family = NFPROTO_UNSPEC, |
| .checkentry = connmark_mt_check, |
| .match = connmark_mt, |
| .matchsize = sizeof(struct xt_connmark_mtinfo1), |
| .destroy = connmark_mt_destroy, |
| .me = THIS_MODULE, |
| }; |
| |
| static int __init connmark_mt_init(void) |
| { |
| int ret; |
| |
| ret = xt_register_target(&connmark_tg_reg); |
| if (ret < 0) |
| return ret; |
| ret = xt_register_match(&connmark_mt_reg); |
| if (ret < 0) { |
| xt_unregister_target(&connmark_tg_reg); |
| return ret; |
| } |
| return 0; |
| } |
| |
| static void __exit connmark_mt_exit(void) |
| { |
| xt_unregister_match(&connmark_mt_reg); |
| xt_unregister_target(&connmark_tg_reg); |
| } |
| |
| module_init(connmark_mt_init); |
| module_exit(connmark_mt_exit); |