mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-27 19:29:37 +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>
327 lines
9.5 KiB
C
327 lines
9.5 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
|
|
/*
|
|
* xt_conntrack - Netfilter module to match connection tracking
|
|
* information. (Superset of Rusty's minimalistic state match.)
|
|
*
|
|
* (C) 2001 Marc Boucher (marc@mbsi.ca).
|
|
* (C) 2006-2012 Patrick McHardy <kaber@trash.net>
|
|
* Copyright © CC Computer Consultants GmbH, 2007 - 2008
|
|
*/
|
|
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
|
|
#include <linux/module.h>
|
|
#include <linux/skbuff.h>
|
|
#include <net/ipv6.h>
|
|
#include <linux/netfilter/x_tables.h>
|
|
#include <linux/netfilter/xt_conntrack.h>
|
|
#include <net/netfilter/nf_conntrack.h>
|
|
|
|
MODULE_LICENSE("GPL");
|
|
MODULE_AUTHOR("Marc Boucher <marc@mbsi.ca>");
|
|
MODULE_AUTHOR("Jan Engelhardt <jengelh@medozas.de>");
|
|
MODULE_DESCRIPTION("Xtables: connection tracking state match");
|
|
MODULE_ALIAS("ipt_conntrack");
|
|
MODULE_ALIAS("ip6t_conntrack");
|
|
|
|
static bool
|
|
conntrack_addrcmp(const union nf_inet_addr *kaddr,
|
|
const union nf_inet_addr *uaddr,
|
|
const union nf_inet_addr *umask, unsigned int l3proto)
|
|
{
|
|
if (l3proto == NFPROTO_IPV4)
|
|
return ((kaddr->ip ^ uaddr->ip) & umask->ip) == 0;
|
|
else if (l3proto == NFPROTO_IPV6)
|
|
return ipv6_masked_addr_cmp(&kaddr->in6, &umask->in6,
|
|
&uaddr->in6) == 0;
|
|
else
|
|
return false;
|
|
}
|
|
|
|
static inline bool
|
|
conntrack_mt_origsrc(const struct nf_conn *ct,
|
|
const struct xt_conntrack_mtinfo2 *info,
|
|
u_int8_t family)
|
|
{
|
|
return conntrack_addrcmp(&ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.u3,
|
|
&info->origsrc_addr, &info->origsrc_mask, family);
|
|
}
|
|
|
|
static inline bool
|
|
conntrack_mt_origdst(const struct nf_conn *ct,
|
|
const struct xt_conntrack_mtinfo2 *info,
|
|
u_int8_t family)
|
|
{
|
|
return conntrack_addrcmp(&ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.u3,
|
|
&info->origdst_addr, &info->origdst_mask, family);
|
|
}
|
|
|
|
static inline bool
|
|
conntrack_mt_replsrc(const struct nf_conn *ct,
|
|
const struct xt_conntrack_mtinfo2 *info,
|
|
u_int8_t family)
|
|
{
|
|
return conntrack_addrcmp(&ct->tuplehash[IP_CT_DIR_REPLY].tuple.src.u3,
|
|
&info->replsrc_addr, &info->replsrc_mask, family);
|
|
}
|
|
|
|
static inline bool
|
|
conntrack_mt_repldst(const struct nf_conn *ct,
|
|
const struct xt_conntrack_mtinfo2 *info,
|
|
u_int8_t family)
|
|
{
|
|
return conntrack_addrcmp(&ct->tuplehash[IP_CT_DIR_REPLY].tuple.dst.u3,
|
|
&info->repldst_addr, &info->repldst_mask, family);
|
|
}
|
|
|
|
static inline bool
|
|
ct_proto_port_check(const struct xt_conntrack_mtinfo2 *info,
|
|
const struct nf_conn *ct)
|
|
{
|
|
const struct nf_conntrack_tuple *tuple;
|
|
|
|
tuple = &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple;
|
|
if ((info->match_flags & XT_CONNTRACK_PROTO) &&
|
|
(nf_ct_protonum(ct) == info->l4proto) ^
|
|
!(info->invert_flags & XT_CONNTRACK_PROTO))
|
|
return false;
|
|
|
|
/* Shortcut to match all recognized protocols by using ->src.all. */
|
|
if ((info->match_flags & XT_CONNTRACK_ORIGSRC_PORT) &&
|
|
(tuple->src.u.all == info->origsrc_port) ^
|
|
!(info->invert_flags & XT_CONNTRACK_ORIGSRC_PORT))
|
|
return false;
|
|
|
|
if ((info->match_flags & XT_CONNTRACK_ORIGDST_PORT) &&
|
|
(tuple->dst.u.all == info->origdst_port) ^
|
|
!(info->invert_flags & XT_CONNTRACK_ORIGDST_PORT))
|
|
return false;
|
|
|
|
tuple = &ct->tuplehash[IP_CT_DIR_REPLY].tuple;
|
|
|
|
if ((info->match_flags & XT_CONNTRACK_REPLSRC_PORT) &&
|
|
(tuple->src.u.all == info->replsrc_port) ^
|
|
!(info->invert_flags & XT_CONNTRACK_REPLSRC_PORT))
|
|
return false;
|
|
|
|
if ((info->match_flags & XT_CONNTRACK_REPLDST_PORT) &&
|
|
(tuple->dst.u.all == info->repldst_port) ^
|
|
!(info->invert_flags & XT_CONNTRACK_REPLDST_PORT))
|
|
return false;
|
|
|
|
return true;
|
|
}
|
|
|
|
static inline bool
|
|
port_match(u16 min, u16 max, u16 port, bool invert)
|
|
{
|
|
return (port >= min && port <= max) ^ invert;
|
|
}
|
|
|
|
static inline bool
|
|
ct_proto_port_check_v3(const struct xt_conntrack_mtinfo3 *info,
|
|
const struct nf_conn *ct)
|
|
{
|
|
const struct nf_conntrack_tuple *tuple;
|
|
|
|
tuple = &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple;
|
|
if ((info->match_flags & XT_CONNTRACK_PROTO) &&
|
|
(nf_ct_protonum(ct) == info->l4proto) ^
|
|
!(info->invert_flags & XT_CONNTRACK_PROTO))
|
|
return false;
|
|
|
|
/* Shortcut to match all recognized protocols by using ->src.all. */
|
|
if ((info->match_flags & XT_CONNTRACK_ORIGSRC_PORT) &&
|
|
!port_match(info->origsrc_port, info->origsrc_port_high,
|
|
ntohs(tuple->src.u.all),
|
|
info->invert_flags & XT_CONNTRACK_ORIGSRC_PORT))
|
|
return false;
|
|
|
|
if ((info->match_flags & XT_CONNTRACK_ORIGDST_PORT) &&
|
|
!port_match(info->origdst_port, info->origdst_port_high,
|
|
ntohs(tuple->dst.u.all),
|
|
info->invert_flags & XT_CONNTRACK_ORIGDST_PORT))
|
|
return false;
|
|
|
|
tuple = &ct->tuplehash[IP_CT_DIR_REPLY].tuple;
|
|
|
|
if ((info->match_flags & XT_CONNTRACK_REPLSRC_PORT) &&
|
|
!port_match(info->replsrc_port, info->replsrc_port_high,
|
|
ntohs(tuple->src.u.all),
|
|
info->invert_flags & XT_CONNTRACK_REPLSRC_PORT))
|
|
return false;
|
|
|
|
if ((info->match_flags & XT_CONNTRACK_REPLDST_PORT) &&
|
|
!port_match(info->repldst_port, info->repldst_port_high,
|
|
ntohs(tuple->dst.u.all),
|
|
info->invert_flags & XT_CONNTRACK_REPLDST_PORT))
|
|
return false;
|
|
|
|
return true;
|
|
}
|
|
|
|
static bool
|
|
conntrack_mt(const struct sk_buff *skb, struct xt_action_param *par,
|
|
u16 state_mask, u16 status_mask)
|
|
{
|
|
const struct xt_conntrack_mtinfo2 *info = par->matchinfo;
|
|
enum ip_conntrack_info ctinfo;
|
|
const struct nf_conn *ct;
|
|
unsigned int statebit;
|
|
|
|
ct = nf_ct_get(skb, &ctinfo);
|
|
|
|
if (ct)
|
|
statebit = XT_CONNTRACK_STATE_BIT(ctinfo);
|
|
else if (ctinfo == IP_CT_UNTRACKED)
|
|
statebit = XT_CONNTRACK_STATE_UNTRACKED;
|
|
else
|
|
statebit = XT_CONNTRACK_STATE_INVALID;
|
|
|
|
if (info->match_flags & XT_CONNTRACK_STATE) {
|
|
if (ct != NULL) {
|
|
if (test_bit(IPS_SRC_NAT_BIT, &ct->status))
|
|
statebit |= XT_CONNTRACK_STATE_SNAT;
|
|
if (test_bit(IPS_DST_NAT_BIT, &ct->status))
|
|
statebit |= XT_CONNTRACK_STATE_DNAT;
|
|
}
|
|
if (!!(state_mask & statebit) ^
|
|
!(info->invert_flags & XT_CONNTRACK_STATE))
|
|
return false;
|
|
}
|
|
|
|
if (ct == NULL)
|
|
return info->match_flags & XT_CONNTRACK_STATE;
|
|
if ((info->match_flags & XT_CONNTRACK_DIRECTION) &&
|
|
(CTINFO2DIR(ctinfo) == IP_CT_DIR_ORIGINAL) ^
|
|
!(info->invert_flags & XT_CONNTRACK_DIRECTION))
|
|
return false;
|
|
|
|
if (info->match_flags & XT_CONNTRACK_ORIGSRC)
|
|
if (conntrack_mt_origsrc(ct, info, xt_family(par)) ^
|
|
!(info->invert_flags & XT_CONNTRACK_ORIGSRC))
|
|
return false;
|
|
|
|
if (info->match_flags & XT_CONNTRACK_ORIGDST)
|
|
if (conntrack_mt_origdst(ct, info, xt_family(par)) ^
|
|
!(info->invert_flags & XT_CONNTRACK_ORIGDST))
|
|
return false;
|
|
|
|
if (info->match_flags & XT_CONNTRACK_REPLSRC)
|
|
if (conntrack_mt_replsrc(ct, info, xt_family(par)) ^
|
|
!(info->invert_flags & XT_CONNTRACK_REPLSRC))
|
|
return false;
|
|
|
|
if (info->match_flags & XT_CONNTRACK_REPLDST)
|
|
if (conntrack_mt_repldst(ct, info, xt_family(par)) ^
|
|
!(info->invert_flags & XT_CONNTRACK_REPLDST))
|
|
return false;
|
|
|
|
if (par->match->revision != 3) {
|
|
if (!ct_proto_port_check(info, ct))
|
|
return false;
|
|
} else {
|
|
if (!ct_proto_port_check_v3(par->matchinfo, ct))
|
|
return false;
|
|
}
|
|
|
|
if ((info->match_flags & XT_CONNTRACK_STATUS) &&
|
|
(!!(status_mask & ct->status) ^
|
|
!(info->invert_flags & XT_CONNTRACK_STATUS)))
|
|
return false;
|
|
|
|
if (info->match_flags & XT_CONNTRACK_EXPIRES) {
|
|
unsigned long expires = nf_ct_expires(ct) / HZ;
|
|
|
|
if ((expires >= info->expires_min &&
|
|
expires <= info->expires_max) ^
|
|
!(info->invert_flags & XT_CONNTRACK_EXPIRES))
|
|
return false;
|
|
}
|
|
return true;
|
|
}
|
|
|
|
static bool
|
|
conntrack_mt_v1(const struct sk_buff *skb, struct xt_action_param *par)
|
|
{
|
|
const struct xt_conntrack_mtinfo1 *info = par->matchinfo;
|
|
|
|
return conntrack_mt(skb, par, info->state_mask, info->status_mask);
|
|
}
|
|
|
|
static bool
|
|
conntrack_mt_v2(const struct sk_buff *skb, struct xt_action_param *par)
|
|
{
|
|
const struct xt_conntrack_mtinfo2 *info = par->matchinfo;
|
|
|
|
return conntrack_mt(skb, par, info->state_mask, info->status_mask);
|
|
}
|
|
|
|
static bool
|
|
conntrack_mt_v3(const struct sk_buff *skb, struct xt_action_param *par)
|
|
{
|
|
const struct xt_conntrack_mtinfo3 *info = par->matchinfo;
|
|
|
|
return conntrack_mt(skb, par, info->state_mask, info->status_mask);
|
|
}
|
|
|
|
static int conntrack_mt_check(const struct xt_mtchk_param *par)
|
|
{
|
|
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;
|
|
}
|
|
|
|
static void conntrack_mt_destroy(const struct xt_mtdtor_param *par)
|
|
{
|
|
nf_ct_netns_put(par->net, par->family);
|
|
}
|
|
|
|
static struct xt_match conntrack_mt_reg[] __read_mostly = {
|
|
{
|
|
.name = "conntrack",
|
|
.revision = 1,
|
|
.family = NFPROTO_UNSPEC,
|
|
.matchsize = sizeof(struct xt_conntrack_mtinfo1),
|
|
.match = conntrack_mt_v1,
|
|
.checkentry = conntrack_mt_check,
|
|
.destroy = conntrack_mt_destroy,
|
|
.me = THIS_MODULE,
|
|
},
|
|
{
|
|
.name = "conntrack",
|
|
.revision = 2,
|
|
.family = NFPROTO_UNSPEC,
|
|
.matchsize = sizeof(struct xt_conntrack_mtinfo2),
|
|
.match = conntrack_mt_v2,
|
|
.checkentry = conntrack_mt_check,
|
|
.destroy = conntrack_mt_destroy,
|
|
.me = THIS_MODULE,
|
|
},
|
|
{
|
|
.name = "conntrack",
|
|
.revision = 3,
|
|
.family = NFPROTO_UNSPEC,
|
|
.matchsize = sizeof(struct xt_conntrack_mtinfo3),
|
|
.match = conntrack_mt_v3,
|
|
.checkentry = conntrack_mt_check,
|
|
.destroy = conntrack_mt_destroy,
|
|
.me = THIS_MODULE,
|
|
},
|
|
};
|
|
|
|
static int __init conntrack_mt_init(void)
|
|
{
|
|
return xt_register_matches(conntrack_mt_reg,
|
|
ARRAY_SIZE(conntrack_mt_reg));
|
|
}
|
|
|
|
static void __exit conntrack_mt_exit(void)
|
|
{
|
|
xt_unregister_matches(conntrack_mt_reg, ARRAY_SIZE(conntrack_mt_reg));
|
|
}
|
|
|
|
module_init(conntrack_mt_init);
|
|
module_exit(conntrack_mt_exit);
|