[deliverable/linux.git] / net / netfilter / xt_conntrack.c

/*
 *	xt_conntrack - Netfilter module to match connection tracking
 *	information. (Superset of Rusty's minimalistic state match.)
 *
 *	(C) 2001  Marc Boucher (marc@mbsi.ca).
 *	Copyright © CC Computer Consultants GmbH, 2007 - 2008
 *
 *	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.
 */

#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@computergmbh.de>");
MODULE_DESCRIPTION("Xtables: connection tracking state match");
MODULE_ALIAS("ipt_conntrack");
MODULE_ALIAS("ip6t_conntrack");

static bool
conntrack_mt_v0(const struct sk_buff *skb, const struct net_device *in,
                const struct net_device *out, const struct xt_match *match,
                const void *matchinfo, int offset, unsigned int protoff,
                bool *hotdrop)
{
	const struct xt_conntrack_info *sinfo = matchinfo;
	const struct nf_conn *ct;
	enum ip_conntrack_info ctinfo;
	unsigned int statebit;

	ct = nf_ct_get(skb, &ctinfo);

#define FWINV(bool, invflg) ((bool) ^ !!(sinfo->invflags & (invflg)))

	if (ct == &nf_conntrack_untracked)
		statebit = XT_CONNTRACK_STATE_UNTRACKED;
	else if (ct)
		statebit = XT_CONNTRACK_STATE_BIT(ctinfo);
	else
		statebit = XT_CONNTRACK_STATE_INVALID;

	if (sinfo->flags & XT_CONNTRACK_STATE) {
		if (ct) {
			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 (FWINV((statebit & sinfo->statemask) == 0,
			  XT_CONNTRACK_STATE))
			return false;
	}

	if (ct == NULL) {
		if (sinfo->flags & ~XT_CONNTRACK_STATE)
			return false;
		return true;
	}

	if (sinfo->flags & XT_CONNTRACK_PROTO &&
	    FWINV(ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.protonum !=
		  sinfo->tuple[IP_CT_DIR_ORIGINAL].dst.protonum,
		  XT_CONNTRACK_PROTO))
		return false;

	if (sinfo->flags & XT_CONNTRACK_ORIGSRC &&
	    FWINV((ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.u3.ip &
		   sinfo->sipmsk[IP_CT_DIR_ORIGINAL].s_addr) !=
		  sinfo->tuple[IP_CT_DIR_ORIGINAL].src.ip,
		  XT_CONNTRACK_ORIGSRC))
		return false;

	if (sinfo->flags & XT_CONNTRACK_ORIGDST &&
	    FWINV((ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.u3.ip &
		   sinfo->dipmsk[IP_CT_DIR_ORIGINAL].s_addr) !=
		  sinfo->tuple[IP_CT_DIR_ORIGINAL].dst.ip,
		  XT_CONNTRACK_ORIGDST))
		return false;

	if (sinfo->flags & XT_CONNTRACK_REPLSRC &&
	    FWINV((ct->tuplehash[IP_CT_DIR_REPLY].tuple.src.u3.ip &
		   sinfo->sipmsk[IP_CT_DIR_REPLY].s_addr) !=
		  sinfo->tuple[IP_CT_DIR_REPLY].src.ip,
		  XT_CONNTRACK_REPLSRC))
		return false;

	if (sinfo->flags & XT_CONNTRACK_REPLDST &&
	    FWINV((ct->tuplehash[IP_CT_DIR_REPLY].tuple.dst.u3.ip &
		   sinfo->dipmsk[IP_CT_DIR_REPLY].s_addr) !=
		  sinfo->tuple[IP_CT_DIR_REPLY].dst.ip,
		  XT_CONNTRACK_REPLDST))
		return false;

	if (sinfo->flags & XT_CONNTRACK_STATUS &&
	    FWINV((ct->status & sinfo->statusmask) == 0,
		  XT_CONNTRACK_STATUS))
		return false;

	if(sinfo->flags & XT_CONNTRACK_EXPIRES) {
		unsigned long expires = timer_pending(&ct->timeout) ?
					(ct->timeout.expires - jiffies)/HZ : 0;

		if (FWINV(!(expires >= sinfo->expires_min &&
			    expires <= sinfo->expires_max),
			  XT_CONNTRACK_EXPIRES))
			return false;
	}
	return true;
#undef FWINV
}

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 == AF_INET)
		return ((kaddr->ip ^ uaddr->ip) & umask->ip) == 0;
	else if (l3proto == AF_INET6)
		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_mtinfo1 *info,
                     unsigned int 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_mtinfo1 *info,
                     unsigned int 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_mtinfo1 *info,
                     unsigned int 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_mtinfo1 *info,
                     unsigned int 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_mtinfo1 *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) &&
	    (tuple->dst.protonum == 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 bool
conntrack_mt(const struct sk_buff *skb, const struct net_device *in,
             const struct net_device *out, const struct xt_match *match,
             const void *matchinfo, int offset, unsigned int protoff,
             bool *hotdrop)
{
	const struct xt_conntrack_mtinfo1 *info = matchinfo;
	enum ip_conntrack_info ctinfo;
	const struct nf_conn *ct;
	unsigned int statebit;

	ct = nf_ct_get(skb, &ctinfo);

	if (ct == &nf_conntrack_untracked)
		statebit = XT_CONNTRACK_STATE_UNTRACKED;
	else if (ct != NULL)
		statebit = XT_CONNTRACK_STATE_BIT(ctinfo);
	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 (!!(info->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, match->family) ^
		    !(info->invert_flags & XT_CONNTRACK_ORIGSRC))
			return false;

	if (info->match_flags & XT_CONNTRACK_ORIGDST)
		if (conntrack_mt_origdst(ct, info, match->family) ^
		    !(info->invert_flags & XT_CONNTRACK_ORIGDST))
			return false;

	if (info->match_flags & XT_CONNTRACK_REPLSRC)
		if (conntrack_mt_replsrc(ct, info, match->family) ^
		    !(info->invert_flags & XT_CONNTRACK_REPLSRC))
			return false;

	if (info->match_flags & XT_CONNTRACK_REPLDST)
		if (conntrack_mt_repldst(ct, info, match->family) ^
		    !(info->invert_flags & XT_CONNTRACK_REPLDST))
			return false;

	if (!ct_proto_port_check(info, ct))
		return false;

	if ((info->match_flags & XT_CONNTRACK_STATUS) &&
	    (!!(info->status_mask & ct->status) ^
	    !(info->invert_flags & XT_CONNTRACK_STATUS)))
		return false;

	if (info->match_flags & XT_CONNTRACK_EXPIRES) {
		unsigned long expires = 0;

		if (timer_pending(&ct->timeout))
			expires = (ct->timeout.expires - jiffies) / HZ;
		if ((expires >= info->expires_min &&
		    expires <= info->expires_max) ^
		    !(info->invert_flags & XT_CONNTRACK_EXPIRES))
			return false;
	}
	return true;
}

static bool
conntrack_mt_check(const char *tablename, const void *ip,
                   const struct xt_match *match, void *matchinfo,
                   unsigned int hook_mask)
{
	if (nf_ct_l3proto_try_module_get(match->family) < 0) {
		printk(KERN_WARNING "can't load conntrack support for "
				    "proto=%u\n", match->family);
		return false;
	}
	return true;
}

static void
conntrack_mt_destroy(const struct xt_match *match, void *matchinfo)
{
	nf_ct_l3proto_module_put(match->family);
}

#ifdef CONFIG_COMPAT
struct compat_xt_conntrack_info
{
	compat_uint_t			statemask;
	compat_uint_t			statusmask;
	struct ip_conntrack_old_tuple	tuple[IP_CT_DIR_MAX];
	struct in_addr			sipmsk[IP_CT_DIR_MAX];
	struct in_addr			dipmsk[IP_CT_DIR_MAX];
	compat_ulong_t			expires_min;
	compat_ulong_t			expires_max;
	u_int8_t			flags;
	u_int8_t			invflags;
};

static void conntrack_mt_compat_from_user_v0(void *dst, void *src)
{
	const struct compat_xt_conntrack_info *cm = src;
	struct xt_conntrack_info m = {
		.statemask	= cm->statemask,
		.statusmask	= cm->statusmask,
		.expires_min	= cm->expires_min,
		.expires_max	= cm->expires_max,
		.flags		= cm->flags,
		.invflags	= cm->invflags,
	};
	memcpy(m.tuple, cm->tuple, sizeof(m.tuple));
	memcpy(m.sipmsk, cm->sipmsk, sizeof(m.sipmsk));
	memcpy(m.dipmsk, cm->dipmsk, sizeof(m.dipmsk));
	memcpy(dst, &m, sizeof(m));
}

static int conntrack_mt_compat_to_user_v0(void __user *dst, void *src)
{
	const struct xt_conntrack_info *m = src;
	struct compat_xt_conntrack_info cm = {
		.statemask	= m->statemask,
		.statusmask	= m->statusmask,
		.expires_min	= m->expires_min,
		.expires_max	= m->expires_max,
		.flags		= m->flags,
		.invflags	= m->invflags,
	};
	memcpy(cm.tuple, m->tuple, sizeof(cm.tuple));
	memcpy(cm.sipmsk, m->sipmsk, sizeof(cm.sipmsk));
	memcpy(cm.dipmsk, m->dipmsk, sizeof(cm.dipmsk));
	return copy_to_user(dst, &cm, sizeof(cm)) ? -EFAULT : 0;
}
#endif

static struct xt_match conntrack_mt_reg[] __read_mostly = {
	{
		.name       = "conntrack",
		.revision   = 0,
		.family     = AF_INET,
		.match      = conntrack_mt_v0,
		.checkentry = conntrack_mt_check,
		.destroy    = conntrack_mt_destroy,
		.matchsize  = sizeof(struct xt_conntrack_info),
		.me         = THIS_MODULE,
#ifdef CONFIG_COMPAT
		.compatsize       = sizeof(struct compat_xt_conntrack_info),
		.compat_from_user = conntrack_mt_compat_from_user_v0,
		.compat_to_user   = conntrack_mt_compat_to_user_v0,
#endif
	},
	{
		.name       = "conntrack",
		.revision   = 1,
		.family     = AF_INET,
		.matchsize  = sizeof(struct xt_conntrack_mtinfo1),
		.match      = conntrack_mt,
		.checkentry = conntrack_mt_check,
		.destroy    = conntrack_mt_destroy,
		.me         = THIS_MODULE,
	},
	{
		.name       = "conntrack",
		.revision   = 1,
		.family     = AF_INET6,
		.matchsize  = sizeof(struct xt_conntrack_mtinfo1),
		.match      = conntrack_mt,
		.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);
Commit	Line	Data
64eb12f9 JE	1	/*
	2	* xt_conntrack - Netfilter module to match connection tracking
	3	* information. (Superset of Rusty's minimalistic state match.)
1da177e4	4	*
64eb12f9 JE	5	* (C) 2001 Marc Boucher (marc@mbsi.ca).
64eb12f9 JE	6	* Copyright © CC Computer Consultants GmbH, 2007 - 2008
1da177e4	7	*
64eb12f9 JE	8	* This program is free software; you can redistribute it and/or modify
	9	* it under the terms of the GNU General Public License version 2 as
	10	* published by the Free Software Foundation.
1da177e4 LT	11	*/
	12
	13	#include <linux/module.h>
	14	#include <linux/skbuff.h>
64eb12f9	15	#include <net/ipv6.h>
2e4e6a17 HW	16	#include <linux/netfilter/x_tables.h>
2e4e6a17 HW	17	#include <linux/netfilter/xt_conntrack.h>
587aa641	18	#include <net/netfilter/nf_conntrack.h>
1da177e4 LT	19
	20	MODULE_LICENSE("GPL");
	21	MODULE_AUTHOR("Marc Boucher <marc@mbsi.ca>");
b4164998	22	MODULE_AUTHOR("Jan Engelhardt <jengelh@computergmbh.de>");
2ae15b64	23	MODULE_DESCRIPTION("Xtables: connection tracking state match");
2e4e6a17	24	MODULE_ALIAS("ipt_conntrack");
64eb12f9	25	MODULE_ALIAS("ip6t_conntrack");
1da177e4	26
1d93a9cb	27	static bool
64eb12f9 JE	28	conntrack_mt_v0(const struct sk_buff skb, const struct net_device in,
	29	const struct net_device out, const struct xt_match match,
	30	const void *matchinfo, int offset, unsigned int protoff,
	31	bool *hotdrop)
9fb9cbb1	32	{
2e4e6a17	33	const struct xt_conntrack_info *sinfo = matchinfo;
a47362a2	34	const struct nf_conn *ct;
9fb9cbb1 YK	35	enum ip_conntrack_info ctinfo;
	36	unsigned int statebit;
	37
a47362a2	38	ct = nf_ct_get(skb, &ctinfo);
9fb9cbb1	39
e79ec50b	40	#define FWINV(bool, invflg) ((bool) ^ !!(sinfo->invflags & (invflg)))
9fb9cbb1 YK	41
9fb9cbb1 YK	42	if (ct == &nf_conntrack_untracked)
2e4e6a17	43	statebit = XT_CONNTRACK_STATE_UNTRACKED;
9fb9cbb1	44	else if (ct)
601e68e1 YH	45	statebit = XT_CONNTRACK_STATE_BIT(ctinfo);
	46	else
	47	statebit = XT_CONNTRACK_STATE_INVALID;
	48
50b9f1d5	49	if (sinfo->flags & XT_CONNTRACK_STATE) {
9fb9cbb1	50	if (ct) {
50b9f1d5	51	if (test_bit(IPS_SRC_NAT_BIT, &ct->status))
2e4e6a17	52	statebit \|= XT_CONNTRACK_STATE_SNAT;
50b9f1d5	53	if (test_bit(IPS_DST_NAT_BIT, &ct->status))
2e4e6a17	54	statebit \|= XT_CONNTRACK_STATE_DNAT;
9fb9cbb1	55	}
50b9f1d5 PM	56	if (FWINV((statebit & sinfo->statemask) == 0,
50b9f1d5 PM	57	XT_CONNTRACK_STATE))
1d93a9cb	58	return false;
9fb9cbb1 YK	59	}
9fb9cbb1 YK	60
50b9f1d5 PM	61	if (ct == NULL) {
50b9f1d5 PM	62	if (sinfo->flags & ~XT_CONNTRACK_STATE)
1d93a9cb JE	63	return false;
1d93a9cb JE	64	return true;
9fb9cbb1 YK	65	}
9fb9cbb1 YK	66
50b9f1d5 PM	67	if (sinfo->flags & XT_CONNTRACK_PROTO &&
50b9f1d5 PM	68	FWINV(ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.protonum !=
601e68e1	69	sinfo->tuple[IP_CT_DIR_ORIGINAL].dst.protonum,
50b9f1d5	70	XT_CONNTRACK_PROTO))
1d93a9cb	71	return false;
50b9f1d5 PM	72
	73	if (sinfo->flags & XT_CONNTRACK_ORIGSRC &&
	74	FWINV((ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.u3.ip &
601e68e1	75	sinfo->sipmsk[IP_CT_DIR_ORIGINAL].s_addr) !=
50b9f1d5 PM	76	sinfo->tuple[IP_CT_DIR_ORIGINAL].src.ip,
50b9f1d5 PM	77	XT_CONNTRACK_ORIGSRC))
1d93a9cb	78	return false;
9fb9cbb1	79
50b9f1d5 PM	80	if (sinfo->flags & XT_CONNTRACK_ORIGDST &&
50b9f1d5 PM	81	FWINV((ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.u3.ip &
601e68e1	82	sinfo->dipmsk[IP_CT_DIR_ORIGINAL].s_addr) !=
50b9f1d5 PM	83	sinfo->tuple[IP_CT_DIR_ORIGINAL].dst.ip,
50b9f1d5 PM	84	XT_CONNTRACK_ORIGDST))
1d93a9cb	85	return false;
9fb9cbb1	86
50b9f1d5 PM	87	if (sinfo->flags & XT_CONNTRACK_REPLSRC &&
50b9f1d5 PM	88	FWINV((ct->tuplehash[IP_CT_DIR_REPLY].tuple.src.u3.ip &
601e68e1	89	sinfo->sipmsk[IP_CT_DIR_REPLY].s_addr) !=
50b9f1d5 PM	90	sinfo->tuple[IP_CT_DIR_REPLY].src.ip,
50b9f1d5 PM	91	XT_CONNTRACK_REPLSRC))
1d93a9cb	92	return false;
9fb9cbb1	93
50b9f1d5 PM	94	if (sinfo->flags & XT_CONNTRACK_REPLDST &&
50b9f1d5 PM	95	FWINV((ct->tuplehash[IP_CT_DIR_REPLY].tuple.dst.u3.ip &
601e68e1	96	sinfo->dipmsk[IP_CT_DIR_REPLY].s_addr) !=
50b9f1d5 PM	97	sinfo->tuple[IP_CT_DIR_REPLY].dst.ip,
50b9f1d5 PM	98	XT_CONNTRACK_REPLDST))
1d93a9cb	99	return false;
9fb9cbb1	100
50b9f1d5 PM	101	if (sinfo->flags & XT_CONNTRACK_STATUS &&
50b9f1d5 PM	102	FWINV((ct->status & sinfo->statusmask) == 0,
601e68e1	103	XT_CONNTRACK_STATUS))
1d93a9cb	104	return false;
9fb9cbb1	105
50b9f1d5 PM	106	if(sinfo->flags & XT_CONNTRACK_EXPIRES) {
	107	unsigned long expires = timer_pending(&ct->timeout) ?
	108	(ct->timeout.expires - jiffies)/HZ : 0;
9fb9cbb1	109
50b9f1d5 PM	110	if (FWINV(!(expires >= sinfo->expires_min &&
	111	expires <= sinfo->expires_max),
	112	XT_CONNTRACK_EXPIRES))
1d93a9cb	113	return false;
9fb9cbb1	114	}
1d93a9cb	115	return true;
e79ec50b	116	#undef FWINV
9fb9cbb1 YK	117	}
9fb9cbb1 YK	118
64eb12f9 JE	119	static bool
	120	conntrack_addrcmp(const union nf_inet_addr *kaddr,
	121	const union nf_inet_addr *uaddr,
	122	const union nf_inet_addr *umask, unsigned int l3proto)
	123	{
	124	if (l3proto == AF_INET)
6556874d	125	return ((kaddr->ip ^ uaddr->ip) & umask->ip) == 0;
64eb12f9 JE	126	else if (l3proto == AF_INET6)
	127	return ipv6_masked_addr_cmp(&kaddr->in6, &umask->in6,
	128	&uaddr->in6) == 0;
	129	else
	130	return false;
	131	}
	132
	133	static inline bool
	134	conntrack_mt_origsrc(const struct nf_conn *ct,
	135	const struct xt_conntrack_mtinfo1 *info,
	136	unsigned int family)
	137	{
	138	return conntrack_addrcmp(&ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.u3,
	139	&info->origsrc_addr, &info->origsrc_mask, family);
	140	}
	141
	142	static inline bool
	143	conntrack_mt_origdst(const struct nf_conn *ct,
	144	const struct xt_conntrack_mtinfo1 *info,
	145	unsigned int family)
	146	{
	147	return conntrack_addrcmp(&ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.u3,
	148	&info->origdst_addr, &info->origdst_mask, family);
	149	}
	150
	151	static inline bool
	152	conntrack_mt_replsrc(const struct nf_conn *ct,
	153	const struct xt_conntrack_mtinfo1 *info,
	154	unsigned int family)
	155	{
	156	return conntrack_addrcmp(&ct->tuplehash[IP_CT_DIR_REPLY].tuple.src.u3,
	157	&info->replsrc_addr, &info->replsrc_mask, family);
	158	}
	159
	160	static inline bool
	161	conntrack_mt_repldst(const struct nf_conn *ct,
	162	const struct xt_conntrack_mtinfo1 *info,
	163	unsigned int family)
	164	{
	165	return conntrack_addrcmp(&ct->tuplehash[IP_CT_DIR_REPLY].tuple.dst.u3,
	166	&info->repldst_addr, &info->repldst_mask, family);
	167	}
	168
b4164998 JE	169	static inline bool
	170	ct_proto_port_check(const struct xt_conntrack_mtinfo1 *info,
	171	const struct nf_conn *ct)
	172	{
	173	const struct nf_conntrack_tuple *tuple;
	174
	175	tuple = &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple;
	176	if ((info->match_flags & XT_CONNTRACK_PROTO) &&
	177	(tuple->dst.protonum == info->l4proto) ^
	178	!(info->invert_flags & XT_CONNTRACK_PROTO))
	179	return false;
	180
	181	/* Shortcut to match all recognized protocols by using ->src.all. */
	182	if ((info->match_flags & XT_CONNTRACK_ORIGSRC_PORT) &&
	183	(tuple->src.u.all == info->origsrc_port) ^
	184	!(info->invert_flags & XT_CONNTRACK_ORIGSRC_PORT))
	185	return false;
	186
	187	if ((info->match_flags & XT_CONNTRACK_ORIGDST_PORT) &&
	188	(tuple->dst.u.all == info->origdst_port) ^
	189	!(info->invert_flags & XT_CONNTRACK_ORIGDST_PORT))
	190	return false;
	191
	192	tuple = &ct->tuplehash[IP_CT_DIR_REPLY].tuple;
	193
	194	if ((info->match_flags & XT_CONNTRACK_REPLSRC_PORT) &&
	195	(tuple->src.u.all == info->replsrc_port) ^
	196	!(info->invert_flags & XT_CONNTRACK_REPLSRC_PORT))
	197	return false;
	198
	199	if ((info->match_flags & XT_CONNTRACK_REPLDST_PORT) &&
	200	(tuple->dst.u.all == info->repldst_port) ^
	201	!(info->invert_flags & XT_CONNTRACK_REPLDST_PORT))
	202	return false;
	203
	204	return true;
	205	}
	206
64eb12f9 JE	207	static bool
	208	conntrack_mt(const struct sk_buff skb, const struct net_device in,
	209	const struct net_device out, const struct xt_match match,
	210	const void *matchinfo, int offset, unsigned int protoff,
	211	bool *hotdrop)
	212	{
	213	const struct xt_conntrack_mtinfo1 *info = matchinfo;
	214	enum ip_conntrack_info ctinfo;
	215	const struct nf_conn *ct;
	216	unsigned int statebit;
	217
	218	ct = nf_ct_get(skb, &ctinfo);
	219
	220	if (ct == &nf_conntrack_untracked)
	221	statebit = XT_CONNTRACK_STATE_UNTRACKED;
	222	else if (ct != NULL)
	223	statebit = XT_CONNTRACK_STATE_BIT(ctinfo);
	224	else
	225	statebit = XT_CONNTRACK_STATE_INVALID;
	226
	227	if (info->match_flags & XT_CONNTRACK_STATE) {
	228	if (ct != NULL) {
	229	if (test_bit(IPS_SRC_NAT_BIT, &ct->status))
	230	statebit \|= XT_CONNTRACK_STATE_SNAT;
	231	if (test_bit(IPS_DST_NAT_BIT, &ct->status))
	232	statebit \|= XT_CONNTRACK_STATE_DNAT;
	233	}
d61f89e9	234	if (!!(info->state_mask & statebit) ^
64eb12f9 JE	235	!(info->invert_flags & XT_CONNTRACK_STATE))
	236	return false;
	237	}
	238
	239	if (ct == NULL)
	240	return info->match_flags & XT_CONNTRACK_STATE;
b4164998 JE	241	if ((info->match_flags & XT_CONNTRACK_DIRECTION) &&
	242	(CTINFO2DIR(ctinfo) == IP_CT_DIR_ORIGINAL) ^
	243	!!(info->invert_flags & XT_CONNTRACK_DIRECTION))
64eb12f9 JE	244	return false;
	245
	246	if (info->match_flags & XT_CONNTRACK_ORIGSRC)
	247	if (conntrack_mt_origsrc(ct, info, match->family) ^
	248	!(info->invert_flags & XT_CONNTRACK_ORIGSRC))
	249	return false;
	250
	251	if (info->match_flags & XT_CONNTRACK_ORIGDST)
	252	if (conntrack_mt_origdst(ct, info, match->family) ^
	253	!(info->invert_flags & XT_CONNTRACK_ORIGDST))
	254	return false;
	255
	256	if (info->match_flags & XT_CONNTRACK_REPLSRC)
	257	if (conntrack_mt_replsrc(ct, info, match->family) ^
	258	!(info->invert_flags & XT_CONNTRACK_REPLSRC))
	259	return false;
	260
	261	if (info->match_flags & XT_CONNTRACK_REPLDST)
	262	if (conntrack_mt_repldst(ct, info, match->family) ^
	263	!(info->invert_flags & XT_CONNTRACK_REPLDST))
	264	return false;
	265
b4164998 JE	266	if (!ct_proto_port_check(info, ct))
	267	return false;
	268
64eb12f9 JE	269	if ((info->match_flags & XT_CONNTRACK_STATUS) &&
	270	(!!(info->status_mask & ct->status) ^
	271	!(info->invert_flags & XT_CONNTRACK_STATUS)))
	272	return false;
	273
	274	if (info->match_flags & XT_CONNTRACK_EXPIRES) {
	275	unsigned long expires = 0;
	276
	277	if (timer_pending(&ct->timeout))
	278	expires = (ct->timeout.expires - jiffies) / HZ;
	279	if ((expires >= info->expires_min &&
	280	expires <= info->expires_max) ^
	281	!(info->invert_flags & XT_CONNTRACK_EXPIRES))
	282	return false;
	283	}
	284	return true;
	285	}
	286
ccb79bdc	287	static bool
d3c5ee6d JE	288	conntrack_mt_check(const char tablename, const void ip,
	289	const struct xt_match match, void matchinfo,
	290	unsigned int hook_mask)
b9f78f9f	291	{
b9f78f9f	292	if (nf_ct_l3proto_try_module_get(match->family) < 0) {
fe0b9294	293	printk(KERN_WARNING "can't load conntrack support for "
df54aae0	294	"proto=%u\n", match->family);
ccb79bdc	295	return false;
b9f78f9f	296	}
ccb79bdc	297	return true;
b9f78f9f PNA	298	}
b9f78f9f PNA	299
d3c5ee6d JE	300	static void
d3c5ee6d JE	301	conntrack_mt_destroy(const struct xt_match match, void matchinfo)
b9f78f9f	302	{
b9f78f9f	303	nf_ct_l3proto_module_put(match->family);
b9f78f9f PNA	304	}
b9f78f9f PNA	305
da0dd231 PM	306	#ifdef CONFIG_COMPAT
	307	struct compat_xt_conntrack_info
	308	{
	309	compat_uint_t statemask;
	310	compat_uint_t statusmask;
	311	struct ip_conntrack_old_tuple tuple[IP_CT_DIR_MAX];
	312	struct in_addr sipmsk[IP_CT_DIR_MAX];
	313	struct in_addr dipmsk[IP_CT_DIR_MAX];
	314	compat_ulong_t expires_min;
	315	compat_ulong_t expires_max;
	316	u_int8_t flags;
	317	u_int8_t invflags;
	318	};
	319
64eb12f9	320	static void conntrack_mt_compat_from_user_v0(void dst, void src)
da0dd231	321	{
a47362a2	322	const struct compat_xt_conntrack_info *cm = src;
da0dd231 PM	323	struct xt_conntrack_info m = {
	324	.statemask = cm->statemask,
	325	.statusmask = cm->statusmask,
	326	.expires_min = cm->expires_min,
	327	.expires_max = cm->expires_max,
	328	.flags = cm->flags,
	329	.invflags = cm->invflags,
	330	};
	331	memcpy(m.tuple, cm->tuple, sizeof(m.tuple));
	332	memcpy(m.sipmsk, cm->sipmsk, sizeof(m.sipmsk));
	333	memcpy(m.dipmsk, cm->dipmsk, sizeof(m.dipmsk));
	334	memcpy(dst, &m, sizeof(m));
	335	}
	336
64eb12f9	337	static int conntrack_mt_compat_to_user_v0(void __user dst, void src)
da0dd231	338	{
a47362a2	339	const struct xt_conntrack_info *m = src;
da0dd231 PM	340	struct compat_xt_conntrack_info cm = {
	341	.statemask = m->statemask,
	342	.statusmask = m->statusmask,
	343	.expires_min = m->expires_min,
	344	.expires_max = m->expires_max,
	345	.flags = m->flags,
	346	.invflags = m->invflags,
	347	};
	348	memcpy(cm.tuple, m->tuple, sizeof(cm.tuple));
	349	memcpy(cm.sipmsk, m->sipmsk, sizeof(cm.sipmsk));
	350	memcpy(cm.dipmsk, m->dipmsk, sizeof(cm.dipmsk));
	351	return copy_to_user(dst, &cm, sizeof(cm)) ? -EFAULT : 0;
	352	}
	353	#endif
	354
64eb12f9 JE	355	static struct xt_match conntrack_mt_reg[] __read_mostly = {
	356	{
	357	.name = "conntrack",
	358	.revision = 0,
	359	.family = AF_INET,
	360	.match = conntrack_mt_v0,
	361	.checkentry = conntrack_mt_check,
	362	.destroy = conntrack_mt_destroy,
	363	.matchsize = sizeof(struct xt_conntrack_info),
	364	.me = THIS_MODULE,
da0dd231	365	#ifdef CONFIG_COMPAT
64eb12f9 JE	366	.compatsize = sizeof(struct compat_xt_conntrack_info),
	367	.compat_from_user = conntrack_mt_compat_from_user_v0,
	368	.compat_to_user = conntrack_mt_compat_to_user_v0,
da0dd231	369	#endif
64eb12f9 JE	370	},
	371	{
	372	.name = "conntrack",
	373	.revision = 1,
	374	.family = AF_INET,
	375	.matchsize = sizeof(struct xt_conntrack_mtinfo1),
	376	.match = conntrack_mt,
	377	.checkentry = conntrack_mt_check,
	378	.destroy = conntrack_mt_destroy,
	379	.me = THIS_MODULE,
	380	},
	381	{
	382	.name = "conntrack",
	383	.revision = 1,
	384	.family = AF_INET6,
	385	.matchsize = sizeof(struct xt_conntrack_mtinfo1),
	386	.match = conntrack_mt,
	387	.checkentry = conntrack_mt_check,
	388	.destroy = conntrack_mt_destroy,
	389	.me = THIS_MODULE,
	390	},
1da177e4 LT	391	};
1da177e4 LT	392
d3c5ee6d	393	static int __init conntrack_mt_init(void)
1da177e4	394	{
64eb12f9 JE	395	return xt_register_matches(conntrack_mt_reg,
64eb12f9 JE	396	ARRAY_SIZE(conntrack_mt_reg));
1da177e4 LT	397	}
1da177e4 LT	398
d3c5ee6d	399	static void __exit conntrack_mt_exit(void)
1da177e4	400	{
64eb12f9	401	xt_unregister_matches(conntrack_mt_reg, ARRAY_SIZE(conntrack_mt_reg));
1da177e4 LT	402	}
1da177e4 LT	403
d3c5ee6d JE	404	module_init(conntrack_mt_init);
d3c5ee6d JE	405	module_exit(conntrack_mt_exit);