Пример #1
0
static struct ip_vs_conn *
ah_esp_conn_in_get(int af, const struct sk_buff *skb,
		   const struct ip_vs_iphdr *iph, unsigned int proto_off,
		   int inverse)
{
	struct ip_vs_conn *cp;
	struct ip_vs_conn_param p;
	struct net *net = skb_net(skb);

	ah_esp_conn_fill_param_proto(net, af, iph, inverse, &p);
	cp = ip_vs_conn_in_get(&p);
	if (!cp) {
		/*
		 * We are not sure if the packet is from our
		 * service, so our conn_schedule hook should return NF_ACCEPT
		 */
		IP_VS_DBG_BUF(12, "Unknown ISAKMP entry for outin packet "
			      "%s%s %s->%s\n",
			      inverse ? "ICMP+" : "",
			      ip_vs_proto_get(iph->protocol)->name,
			      IP_VS_DBG_ADDR(af, &iph->saddr),
			      IP_VS_DBG_ADDR(af, &iph->daddr));
	}

	return cp;
}
Пример #2
0
const char * ip_vs_state_name(__u16 proto, int state)
{
    struct ip_vs_protocol *pp = ip_vs_proto_get(proto);

    if (pp == NULL || pp->state_name == NULL)
        return (IPPROTO_IP == proto) ? "NONE" : "ERR!";
    return pp->state_name(state);
}
Пример #3
0
static struct ip_vs_conn *
ah_esp_conn_out_get(int af, const struct sk_buff *skb,
		    const struct ip_vs_iphdr *iph,
		    unsigned int proto_off,
		    int inverse)
{
	struct ip_vs_conn *cp;
	struct ip_vs_conn_param p;
	struct net *net = skb_net(skb);

	ah_esp_conn_fill_param_proto(net, af, iph, inverse, &p);
	cp = ip_vs_conn_out_get(&p);
	if (!cp) {
		IP_VS_DBG_BUF(12, "Unknown ISAKMP entry for inout packet "
			      "%s%s %s->%s\n",
			      inverse ? "ICMP+" : "",
			      ip_vs_proto_get(iph->protocol)->name,
			      IP_VS_DBG_ADDR(af, &iph->saddr),
			      IP_VS_DBG_ADDR(af, &iph->daddr));
	}

	return cp;
}
Пример #4
0
/*
 *	Check if it's for virtual services, look it up,
 *	and send it on its way...
 */
static unsigned int
ip_vs_in(unsigned int hooknum, struct sk_buff **pskb,
	 const struct net_device *in, const struct net_device *out,
	 int (*okfn)(struct sk_buff *))
{
	struct sk_buff	*skb = *pskb;
	struct iphdr	*iph;
	struct ip_vs_protocol *pp;
	struct ip_vs_conn *cp;
	int ret, restart;
	int ihl;

	/*
	 *	Big tappo: only PACKET_HOST (neither loopback nor mcasts)
	 *	... don't know why 1st test DOES NOT include 2nd (?)
	 */
	if (unlikely(skb->pkt_type != PACKET_HOST
		     || skb->dev == &loopback_dev || skb->sk)) {
		IP_VS_DBG(12, "packet type=%d proto=%d daddr=%d.%d.%d.%d ignored\n",
			  skb->pkt_type,
			  ip_hdr(skb)->protocol,
			  NIPQUAD(ip_hdr(skb)->daddr));
		return NF_ACCEPT;
	}

	iph = ip_hdr(skb);
	if (unlikely(iph->protocol == IPPROTO_ICMP)) {
		int related, verdict = ip_vs_in_icmp(pskb, &related, hooknum);

		if (related)
			return verdict;
		skb = *pskb;
		iph = ip_hdr(skb);
	}

	/* Protocol supported? */
	pp = ip_vs_proto_get(iph->protocol);
	if (unlikely(!pp))
		return NF_ACCEPT;

	ihl = iph->ihl << 2;

	/*
	 * Check if the packet belongs to an existing connection entry
	 */
	cp = pp->conn_in_get(skb, pp, iph, ihl, 0);

	if (unlikely(!cp)) {
		int v;

		if (!pp->conn_schedule(skb, pp, &v, &cp))
			return v;
	}

	if (unlikely(!cp)) {
		/* sorry, all this trouble for a no-hit :) */
		IP_VS_DBG_PKT(12, pp, skb, 0,
			      "packet continues traversal as normal");
		return NF_ACCEPT;
	}

	IP_VS_DBG_PKT(11, pp, skb, 0, "Incoming packet");

	/* Check the server status */
	if (cp->dest && !(cp->dest->flags & IP_VS_DEST_F_AVAILABLE)) {
		/* the destination server is not available */

		if (sysctl_ip_vs_expire_nodest_conn) {
			/* try to expire the connection immediately */
			ip_vs_conn_expire_now(cp);
		}
		/* don't restart its timer, and silently
		   drop the packet. */
		__ip_vs_conn_put(cp);
		return NF_DROP;
	}

	ip_vs_in_stats(cp, skb);
	restart = ip_vs_set_state(cp, IP_VS_DIR_INPUT, skb, pp);
	if (cp->packet_xmit)
		ret = cp->packet_xmit(skb, cp, pp);
		/* do not touch skb anymore */
	else {
		IP_VS_DBG_RL("warning: packet_xmit is null");
		ret = NF_ACCEPT;
	}

	/* increase its packet counter and check if it is needed
	   to be synchronized */
	atomic_inc(&cp->in_pkts);
	if ((ip_vs_sync_state & IP_VS_STATE_MASTER) &&
	    (cp->protocol != IPPROTO_TCP ||
	     cp->state == IP_VS_TCP_S_ESTABLISHED) &&
	    (atomic_read(&cp->in_pkts) % sysctl_ip_vs_sync_threshold[1]
	     == sysctl_ip_vs_sync_threshold[0]))
		ip_vs_sync_conn(cp);

	ip_vs_conn_put(cp);
	return ret;
}
Пример #5
0
/*
 *	Handle ICMP messages in the outside-to-inside direction (incoming).
 *	Find any that might be relevant, check against existing connections,
 *	forward to the right destination host if relevant.
 *	Currently handles error types - unreachable, quench, ttl exceeded.
 */
static int
ip_vs_in_icmp(struct sk_buff **pskb, int *related, unsigned int hooknum)
{
	struct sk_buff *skb = *pskb;
	struct iphdr *iph;
	struct icmphdr	_icmph, *ic;
	struct iphdr	_ciph, *cih;	/* The ip header contained within the ICMP */
	struct ip_vs_conn *cp;
	struct ip_vs_protocol *pp;
	unsigned int offset, ihl, verdict;

	*related = 1;

	/* reassemble IP fragments */
	if (ip_hdr(skb)->frag_off & htons(IP_MF | IP_OFFSET)) {
		skb = ip_vs_gather_frags(skb,
					 hooknum == NF_IP_LOCAL_IN ?
					 IP_DEFRAG_VS_IN : IP_DEFRAG_VS_FWD);
		if (!skb)
			return NF_STOLEN;
		*pskb = skb;
	}

	iph = ip_hdr(skb);
	offset = ihl = iph->ihl * 4;
	ic = skb_header_pointer(skb, offset, sizeof(_icmph), &_icmph);
	if (ic == NULL)
		return NF_DROP;

	IP_VS_DBG(12, "Incoming ICMP (%d,%d) %u.%u.%u.%u->%u.%u.%u.%u\n",
		  ic->type, ntohs(icmp_id(ic)),
		  NIPQUAD(iph->saddr), NIPQUAD(iph->daddr));

	/*
	 * Work through seeing if this is for us.
	 * These checks are supposed to be in an order that means easy
	 * things are checked first to speed up processing.... however
	 * this means that some packets will manage to get a long way
	 * down this stack and then be rejected, but that's life.
	 */
	if ((ic->type != ICMP_DEST_UNREACH) &&
	    (ic->type != ICMP_SOURCE_QUENCH) &&
	    (ic->type != ICMP_TIME_EXCEEDED)) {
		*related = 0;
		return NF_ACCEPT;
	}

	/* Now find the contained IP header */
	offset += sizeof(_icmph);
	cih = skb_header_pointer(skb, offset, sizeof(_ciph), &_ciph);
	if (cih == NULL)
		return NF_ACCEPT; /* The packet looks wrong, ignore */

	pp = ip_vs_proto_get(cih->protocol);
	if (!pp)
		return NF_ACCEPT;

	/* Is the embedded protocol header present? */
	if (unlikely(cih->frag_off & htons(IP_OFFSET) &&
		     pp->dont_defrag))
		return NF_ACCEPT;

	IP_VS_DBG_PKT(11, pp, skb, offset, "Checking incoming ICMP for");

	offset += cih->ihl * 4;

	/* The embedded headers contain source and dest in reverse order */
	cp = pp->conn_in_get(skb, pp, cih, offset, 1);
	if (!cp)
		return NF_ACCEPT;

	verdict = NF_DROP;

	/* Ensure the checksum is correct */
	if (!skb_csum_unnecessary(skb) && ip_vs_checksum_complete(skb, ihl)) {
		/* Failed checksum! */
		IP_VS_DBG(1, "Incoming ICMP: failed checksum from %d.%d.%d.%d!\n",
			  NIPQUAD(iph->saddr));
		goto out;
	}

	/* do the statistics and put it back */
	ip_vs_in_stats(cp, skb);
	if (IPPROTO_TCP == cih->protocol || IPPROTO_UDP == cih->protocol)
		offset += 2 * sizeof(__u16);
	verdict = ip_vs_icmp_xmit(skb, cp, pp, offset);
	/* do not touch skb anymore */

  out:
	__ip_vs_conn_put(cp);

	return verdict;
}
Пример #6
0
/*
 *	It is hooked at the NF_IP_FORWARD chain, used only for VS/NAT.
 *	Check if outgoing packet belongs to the established ip_vs_conn,
 *      rewrite addresses of the packet and send it on its way...
 */
static unsigned int
ip_vs_out(unsigned int hooknum, struct sk_buff **pskb,
	  const struct net_device *in, const struct net_device *out,
	  int (*okfn)(struct sk_buff *))
{
	struct sk_buff  *skb = *pskb;
	struct iphdr	*iph;
	struct ip_vs_protocol *pp;
	struct ip_vs_conn *cp;
	int ihl;

	EnterFunction(11);

	if (skb->ipvs_property)
		return NF_ACCEPT;

	iph = ip_hdr(skb);
	if (unlikely(iph->protocol == IPPROTO_ICMP)) {
		int related, verdict = ip_vs_out_icmp(pskb, &related);

		if (related)
			return verdict;
		skb = *pskb;
		iph = ip_hdr(skb);
	}

	pp = ip_vs_proto_get(iph->protocol);
	if (unlikely(!pp))
		return NF_ACCEPT;

	/* reassemble IP fragments */
	if (unlikely(iph->frag_off & htons(IP_MF|IP_OFFSET) &&
		     !pp->dont_defrag)) {
		skb = ip_vs_gather_frags(skb, IP_DEFRAG_VS_OUT);
		if (!skb)
			return NF_STOLEN;
		iph = ip_hdr(skb);
		*pskb = skb;
	}

	ihl = iph->ihl << 2;

	/*
	 * Check if the packet belongs to an existing entry
	 */
	cp = pp->conn_out_get(skb, pp, iph, ihl, 0);

	if (unlikely(!cp)) {
		if (sysctl_ip_vs_nat_icmp_send &&
		    (pp->protocol == IPPROTO_TCP ||
		     pp->protocol == IPPROTO_UDP)) {
			__be16 _ports[2], *pptr;

			pptr = skb_header_pointer(skb, ihl,
						  sizeof(_ports), _ports);
			if (pptr == NULL)
				return NF_ACCEPT;	/* Not for me */
			if (ip_vs_lookup_real_service(iph->protocol,
						      iph->saddr, pptr[0])) {
				/*
				 * Notify the real server: there is no
				 * existing entry if it is not RST
				 * packet or not TCP packet.
				 */
				if (iph->protocol != IPPROTO_TCP
				    || !is_tcp_reset(skb)) {
					icmp_send(skb,ICMP_DEST_UNREACH,
						  ICMP_PORT_UNREACH, 0);
					return NF_DROP;
				}
			}
		}
		IP_VS_DBG_PKT(12, pp, skb, 0,
			      "packet continues traversal as normal");
		return NF_ACCEPT;
	}

	IP_VS_DBG_PKT(11, pp, skb, 0, "Outgoing packet");

	if (!ip_vs_make_skb_writable(pskb, ihl))
		goto drop;

	/* mangle the packet */
	if (pp->snat_handler && !pp->snat_handler(pskb, pp, cp))
		goto drop;
	skb = *pskb;
	ip_hdr(skb)->saddr = cp->vaddr;
	ip_send_check(ip_hdr(skb));

	/* For policy routing, packets originating from this
	 * machine itself may be routed differently to packets
	 * passing through.  We want this packet to be routed as
	 * if it came from this machine itself.  So re-compute
	 * the routing information.
	 */
	if (ip_route_me_harder(pskb, RTN_LOCAL) != 0)
		goto drop;
	skb = *pskb;

	IP_VS_DBG_PKT(10, pp, skb, 0, "After SNAT");

	ip_vs_out_stats(cp, skb);
	ip_vs_set_state(cp, IP_VS_DIR_OUTPUT, skb, pp);
	ip_vs_conn_put(cp);

	skb->ipvs_property = 1;

	LeaveFunction(11);
	return NF_ACCEPT;

  drop:
	ip_vs_conn_put(cp);
	kfree_skb(*pskb);
	return NF_STOLEN;
}
Пример #7
0
/*
 *	Handle ICMP messages in the inside-to-outside direction (outgoing).
 *	Find any that might be relevant, check against existing connections,
 *	forward to the right destination host if relevant.
 *	Currently handles error types - unreachable, quench, ttl exceeded.
 *	(Only used in VS/NAT)
 */
static int ip_vs_out_icmp(struct sk_buff **pskb, int *related)
{
	struct sk_buff *skb = *pskb;
	struct iphdr *iph;
	struct icmphdr	_icmph, *ic;
	struct iphdr	_ciph, *cih;	/* The ip header contained within the ICMP */
	struct ip_vs_conn *cp;
	struct ip_vs_protocol *pp;
	unsigned int offset, ihl, verdict;

	*related = 1;

	/* reassemble IP fragments */
	if (skb->nh.iph->frag_off & __constant_htons(IP_MF|IP_OFFSET)) {
		skb = ip_vs_gather_frags(skb, IP_DEFRAG_VS_OUT);
		if (!skb)
			return NF_STOLEN;
		*pskb = skb;
	}

	iph = skb->nh.iph;
	offset = ihl = iph->ihl * 4;
	ic = skb_header_pointer(skb, offset, sizeof(_icmph), &_icmph);
	if (ic == NULL)
		return NF_DROP;

	IP_VS_DBG(12, "Outgoing ICMP (%d,%d) %u.%u.%u.%u->%u.%u.%u.%u\n",
		  ic->type, ntohs(icmp_id(ic)),
		  NIPQUAD(iph->saddr), NIPQUAD(iph->daddr));

	/*
	 * Work through seeing if this is for us.
	 * These checks are supposed to be in an order that means easy
	 * things are checked first to speed up processing.... however
	 * this means that some packets will manage to get a long way
	 * down this stack and then be rejected, but that's life.
	 */
	if ((ic->type != ICMP_DEST_UNREACH) &&
	    (ic->type != ICMP_SOURCE_QUENCH) &&
	    (ic->type != ICMP_TIME_EXCEEDED)) {
		*related = 0;
		return NF_ACCEPT;
	}

	/* Now find the contained IP header */
	offset += sizeof(_icmph);
	cih = skb_header_pointer(skb, offset, sizeof(_ciph), &_ciph);
	if (cih == NULL)
		return NF_ACCEPT; /* The packet looks wrong, ignore */

	pp = ip_vs_proto_get(cih->protocol);
	if (!pp)
		return NF_ACCEPT;

	/* Is the embedded protocol header present? */
	if (unlikely(cih->frag_off & __constant_htons(IP_OFFSET) &&
		     pp->dont_defrag))
		return NF_ACCEPT;

	IP_VS_DBG_PKT(11, pp, skb, offset, "Checking outgoing ICMP for");

	offset += cih->ihl * 4;

	/* The embedded headers contain source and dest in reverse order */
	cp = pp->conn_out_get(skb, pp, cih, offset, 1);
	if (!cp)
		return NF_ACCEPT;

	verdict = NF_DROP;

	if (IP_VS_FWD_METHOD(cp) != 0) {
		IP_VS_ERR("shouldn't reach here, because the box is on the"
			  "half connection in the tun/dr module.\n");
	}

	/* Ensure the checksum is correct */
	if (skb->ip_summed != CHECKSUM_UNNECESSARY &&
	    ip_vs_checksum_complete(skb, ihl)) {
		/* Failed checksum! */
		IP_VS_DBG(1, "Forward ICMP: failed checksum from %d.%d.%d.%d!\n",
			  NIPQUAD(iph->saddr));
		goto out;
	}

	if (IPPROTO_TCP == cih->protocol || IPPROTO_UDP == cih->protocol)
		offset += 2 * sizeof(__u16);
	if (!ip_vs_make_skb_writable(pskb, offset))
		goto out;
	skb = *pskb;

	ip_vs_nat_icmp(skb, pp, cp, 1);

	/* do the statistics and put it back */
	ip_vs_out_stats(cp, skb);

	skb->ipvs_property = 1;
	verdict = NF_ACCEPT;

  out:
	__ip_vs_conn_put(cp);

	return verdict;
}
/*
 *	It is hooked at the NF_IP_FORWARD chain, used only for VS/NAT.
 *	Check if outgoing packet belongs to the established ip_vs_conn,
 *      rewrite addresses of the packet and send it on its way...
 */
static unsigned int
ip_vs_out(unsigned int hooknum, struct sk_buff **pskb,
	  const struct net_device *in, const struct net_device *out,
	  int (*okfn)(struct sk_buff *))
{
	struct sk_buff  *skb = *pskb;
	struct iphdr	*iph;
	struct ip_vs_protocol *pp;
	struct ip_vs_conn *cp;
	int ihl;

	EnterFunction(11);

	if (skb->nfcache & NFC_IPVS_PROPERTY)
		return NF_ACCEPT;

	if (skb->ip_summed == CHECKSUM_HW) {
		if (skb_checksum_help(pskb, (out == NULL)))
			return NF_DROP;
		if (skb != *pskb)
			skb = *pskb;
	}

	iph = skb->nh.iph;
	if (unlikely(iph->protocol == IPPROTO_ICMP)) {
		int related, verdict = ip_vs_out_icmp(pskb, &related);

		if (related)
			return verdict;
		skb = *pskb;
		iph = skb->nh.iph;
	}

	pp = ip_vs_proto_get(iph->protocol);
	if (unlikely(!pp))
		return NF_ACCEPT;

	/* reassemble IP fragments */
	if (unlikely(iph->frag_off & __constant_htons(IP_MF|IP_OFFSET) &&
		     !pp->dont_defrag)) {
		skb = ip_vs_gather_frags(skb);
		if (!skb)
			return NF_STOLEN;
		iph = skb->nh.iph;
		*pskb = skb;
	}

	ihl = iph->ihl << 2;

	/*
	 * Check if the packet belongs to an existing entry
	 */
	cp = pp->conn_out_get(skb, pp, iph, ihl, 0);

	if (unlikely(!cp)) {
		if (sysctl_ip_vs_nat_icmp_send &&
		    (pp->protocol == IPPROTO_TCP ||
		     pp->protocol == IPPROTO_UDP)) {
			__u16 ports[2];

			if (skb_copy_bits(skb, ihl, ports, sizeof(ports)) < 0)
				return NF_ACCEPT;	/* Not for me */
			if (ip_vs_lookup_real_service(iph->protocol,
						      iph->saddr, ports[0])) {
				/*
				 * Notify the real server: there is no
				 * existing entry if it is not RST
				 * packet or not TCP packet.
				 */
				if (iph->protocol != IPPROTO_TCP
				    || !is_tcp_reset(skb)) {
					icmp_send(skb,ICMP_DEST_UNREACH,
						  ICMP_PORT_UNREACH, 0);
					return NF_DROP;
				}
			}
		}
		IP_VS_DBG_PKT(12, pp, skb, 0,
			      "packet continues traversal as normal");
		return NF_ACCEPT;
	}

	IP_VS_DBG_PKT(11, pp, skb, 0, "Outgoing packet");

	if (!ip_vs_make_skb_writable(pskb, ihl))
		goto drop;

	/* mangle the packet */
	if (pp->snat_handler && !pp->snat_handler(pskb, pp, cp))
		goto drop;
	skb = *pskb;
	skb->nh.iph->saddr = cp->vaddr;
	ip_send_check(skb->nh.iph);

	IP_VS_DBG_PKT(10, pp, skb, 0, "After SNAT");

	ip_vs_out_stats(cp, skb);
	ip_vs_set_state(cp, IP_VS_DIR_OUTPUT, skb, pp);
	ip_vs_conn_put(cp);

	skb->nfcache |= NFC_IPVS_PROPERTY;

	LeaveFunction(11);
	return NF_ACCEPT;

  drop:
	ip_vs_conn_put(cp);
	kfree_skb(*pskb);
	return NF_STOLEN;
}
Пример #9
0
static bool
ipvs_mt(const struct sk_buff *skb, struct xt_action_param *par)
{
	const struct xt_ipvs_mtinfo *data = par->matchinfo;
	struct netns_ipvs *ipvs = net_ipvs(par->net);
	/* ipvs_mt_check ensures that family is only NFPROTO_IPV[46]. */
	const u_int8_t family = par->family;
	struct ip_vs_iphdr iph;
	struct ip_vs_protocol *pp;
	struct ip_vs_conn *cp;
	bool match = true;

	if (data->bitmask == XT_IPVS_IPVS_PROPERTY) {
		match = skb->ipvs_property ^
			!!(data->invert & XT_IPVS_IPVS_PROPERTY);
		goto out;
	}

	/* other flags than XT_IPVS_IPVS_PROPERTY are set */
	if (!skb->ipvs_property) {
		match = false;
		goto out;
	}

	ip_vs_fill_iph_skb(family, skb, true, &iph);

	if (data->bitmask & XT_IPVS_PROTO)
		if ((iph.protocol == data->l4proto) ^
		    !(data->invert & XT_IPVS_PROTO)) {
			match = false;
			goto out;
		}

	pp = ip_vs_proto_get(iph.protocol);
	if (unlikely(!pp)) {
		match = false;
		goto out;
	}

	/*
	 * Check if the packet belongs to an existing entry
	 */
	cp = pp->conn_out_get(ipvs, family, skb, &iph);
	if (unlikely(cp == NULL)) {
		match = false;
		goto out;
	}

	/*
	 * We found a connection, i.e. ct != 0, make sure to call
	 * __ip_vs_conn_put before returning.  In our case jump to out_put_con.
	 */

	if (data->bitmask & XT_IPVS_VPORT)
		if ((cp->vport == data->vport) ^
		    !(data->invert & XT_IPVS_VPORT)) {
			match = false;
			goto out_put_cp;
		}

	if (data->bitmask & XT_IPVS_VPORTCTL)
		if ((cp->control != NULL &&
		     cp->control->vport == data->vportctl) ^
		    !(data->invert & XT_IPVS_VPORTCTL)) {
			match = false;
			goto out_put_cp;
		}

	if (data->bitmask & XT_IPVS_DIR) {
		enum ip_conntrack_info ctinfo;
		struct nf_conn *ct = nf_ct_get(skb, &ctinfo);

		if (ct == NULL || nf_ct_is_untracked(ct)) {
			match = false;
			goto out_put_cp;
		}

		if ((ctinfo >= IP_CT_IS_REPLY) ^
		    !!(data->invert & XT_IPVS_DIR)) {
			match = false;
			goto out_put_cp;
		}
	}

	if (data->bitmask & XT_IPVS_METHOD)
		if (((cp->flags & IP_VS_CONN_F_FWD_MASK) == data->fwd_method) ^
		    !(data->invert & XT_IPVS_METHOD)) {
			match = false;
			goto out_put_cp;
		}

	if (data->bitmask & XT_IPVS_VADDR) {
		if (ipvs_mt_addrcmp(&cp->vaddr, &data->vaddr,
				    &data->vmask, family) ^
		    !(data->invert & XT_IPVS_VADDR)) {
			match = false;
			goto out_put_cp;
		}
	}

out_put_cp:
	__ip_vs_conn_put(cp);
out:
	pr_debug("match=%d\n", match);
	return match;
}
Пример #10
0
static bool
ipvs_mt(const struct sk_buff *skb, struct xt_action_param *par)
{
	const struct xt_ipvs_mtinfo *data = par->matchinfo;
	/*                                                            */
	const u_int8_t family = par->family;
	struct ip_vs_iphdr iph;
	struct ip_vs_protocol *pp;
	struct ip_vs_conn *cp;
	bool match = true;

	if (data->bitmask == XT_IPVS_IPVS_PROPERTY) {
		match = skb->ipvs_property ^
			!!(data->invert & XT_IPVS_IPVS_PROPERTY);
		goto out;
	}

	/*                                                */
	if (!skb->ipvs_property) {
		match = false;
		goto out;
	}

	ip_vs_fill_iphdr(family, skb_network_header(skb), &iph);

	if (data->bitmask & XT_IPVS_PROTO)
		if ((iph.protocol == data->l4proto) ^
		    !(data->invert & XT_IPVS_PROTO)) {
			match = false;
			goto out;
		}

	pp = ip_vs_proto_get(iph.protocol);
	if (unlikely(!pp)) {
		match = false;
		goto out;
	}

	/*
                                                    
  */
	cp = pp->conn_out_get(family, skb, &iph, iph.len, 1 /*         */);
	if (unlikely(cp == NULL)) {
		match = false;
		goto out;
	}

	/*
                                                          
                                                                        
  */

	if (data->bitmask & XT_IPVS_VPORT)
		if ((cp->vport == data->vport) ^
		    !(data->invert & XT_IPVS_VPORT)) {
			match = false;
			goto out_put_cp;
		}

	if (data->bitmask & XT_IPVS_VPORTCTL)
		if ((cp->control != NULL &&
		     cp->control->vport == data->vportctl) ^
		    !(data->invert & XT_IPVS_VPORTCTL)) {
			match = false;
			goto out_put_cp;
		}

	if (data->bitmask & XT_IPVS_DIR) {
		enum ip_conntrack_info ctinfo;
		struct nf_conn *ct = nf_ct_get(skb, &ctinfo);

		if (ct == NULL || nf_ct_is_untracked(ct)) {
			match = false;
			goto out_put_cp;
		}

		if ((ctinfo >= IP_CT_IS_REPLY) ^
		    !!(data->invert & XT_IPVS_DIR)) {
			match = false;
			goto out_put_cp;
		}
	}

	if (data->bitmask & XT_IPVS_METHOD)
		if (((cp->flags & IP_VS_CONN_F_FWD_MASK) == data->fwd_method) ^
		    !(data->invert & XT_IPVS_METHOD)) {
			match = false;
			goto out_put_cp;
		}

	if (data->bitmask & XT_IPVS_VADDR) {
		if (ipvs_mt_addrcmp(&cp->vaddr, &data->vaddr,
				    &data->vmask, family) ^
		    !(data->invert & XT_IPVS_VADDR)) {
			match = false;
			goto out_put_cp;
		}
	}

out_put_cp:
	__ip_vs_conn_put(cp);
out:
	pr_debug("match=%d\n", match);
	return match;
}