diff options
Diffstat (limited to 'net/netfilter/xt_connmark.c')
| -rw-r--r-- | net/netfilter/xt_connmark.c | 167 |
1 files changed, 167 insertions, 0 deletions
diff --git a/net/netfilter/xt_connmark.c b/net/netfilter/xt_connmark.c new file mode 100644 index 00000000..7278145e --- /dev/null +++ b/net/netfilter/xt_connmark.c @@ -0,0 +1,167 @@ +/* + * 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_action_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) +{ + int ret; + + ret = nf_ct_l3proto_try_module_get(par->family); + if (ret < 0) + pr_info("cannot load conntrack support for proto=%u\n", + par->family); + return ret; +} + +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, struct xt_action_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) +{ + int ret; + + ret = nf_ct_l3proto_try_module_get(par->family); + if (ret < 0) + pr_info("cannot load conntrack support for proto=%u\n", + par->family); + return ret; +} + +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); |