mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-23 01:10:04 +00:00
![Thomas Gleixner](/assets/img/avatar_default.png)
Based on 2 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation # extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 4122 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Enrico Weigelt <info@metux.net> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
96 lines
2.3 KiB
C
96 lines
2.3 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
|
|
/* iptables module to match on related connections */
|
|
/*
|
|
* (C) 2001 Martin Josefsson <gandalf@wlug.westbo.se>
|
|
*/
|
|
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
|
|
#include <linux/module.h>
|
|
#include <linux/skbuff.h>
|
|
#include <linux/netfilter.h>
|
|
#include <net/netfilter/nf_conntrack.h>
|
|
#include <net/netfilter/nf_conntrack_core.h>
|
|
#include <net/netfilter/nf_conntrack_helper.h>
|
|
#include <linux/netfilter/x_tables.h>
|
|
#include <linux/netfilter/xt_helper.h>
|
|
|
|
MODULE_LICENSE("GPL");
|
|
MODULE_AUTHOR("Martin Josefsson <gandalf@netfilter.org>");
|
|
MODULE_DESCRIPTION("Xtables: Related connection matching");
|
|
MODULE_ALIAS("ipt_helper");
|
|
MODULE_ALIAS("ip6t_helper");
|
|
|
|
|
|
static bool
|
|
helper_mt(const struct sk_buff *skb, struct xt_action_param *par)
|
|
{
|
|
const struct xt_helper_info *info = par->matchinfo;
|
|
const struct nf_conn *ct;
|
|
const struct nf_conn_help *master_help;
|
|
const struct nf_conntrack_helper *helper;
|
|
enum ip_conntrack_info ctinfo;
|
|
bool ret = info->invert;
|
|
|
|
ct = nf_ct_get(skb, &ctinfo);
|
|
if (!ct || !ct->master)
|
|
return ret;
|
|
|
|
master_help = nfct_help(ct->master);
|
|
if (!master_help)
|
|
return ret;
|
|
|
|
/* rcu_read_lock()ed by nf_hook_thresh */
|
|
helper = rcu_dereference(master_help->helper);
|
|
if (!helper)
|
|
return ret;
|
|
|
|
if (info->name[0] == '\0')
|
|
ret = !ret;
|
|
else
|
|
ret ^= !strncmp(helper->name, info->name,
|
|
strlen(helper->name));
|
|
return ret;
|
|
}
|
|
|
|
static int helper_mt_check(const struct xt_mtchk_param *par)
|
|
{
|
|
struct xt_helper_info *info = par->matchinfo;
|
|
int ret;
|
|
|
|
ret = nf_ct_netns_get(par->net, par->family);
|
|
if (ret < 0) {
|
|
pr_info_ratelimited("cannot load conntrack support for proto=%u\n",
|
|
par->family);
|
|
return ret;
|
|
}
|
|
info->name[sizeof(info->name) - 1] = '\0';
|
|
return 0;
|
|
}
|
|
|
|
static void helper_mt_destroy(const struct xt_mtdtor_param *par)
|
|
{
|
|
nf_ct_netns_put(par->net, par->family);
|
|
}
|
|
|
|
static struct xt_match helper_mt_reg __read_mostly = {
|
|
.name = "helper",
|
|
.revision = 0,
|
|
.family = NFPROTO_UNSPEC,
|
|
.checkentry = helper_mt_check,
|
|
.match = helper_mt,
|
|
.destroy = helper_mt_destroy,
|
|
.matchsize = sizeof(struct xt_helper_info),
|
|
.me = THIS_MODULE,
|
|
};
|
|
|
|
static int __init helper_mt_init(void)
|
|
{
|
|
return xt_register_match(&helper_mt_reg);
|
|
}
|
|
|
|
static void __exit helper_mt_exit(void)
|
|
{
|
|
xt_unregister_match(&helper_mt_reg);
|
|
}
|
|
|
|
module_init(helper_mt_init);
|
|
module_exit(helper_mt_exit);
|