1 files changed, 92 insertions, 7 deletions

diff --git a/net/ipv4/netfilter/ip_nat_core.c b/net/ipv4/netfilter/ip_nat_core.c
index ed4d731880f7..567c802fecf0 100644
--- a/net/ipv4/netfilter/ip_nat_core.c
+++ b/net/ipv4/netfilter/ip_nat_core.c
@@ -47,8 +47,39 @@ DEFINE_RWLOCK(ip_nat_lock);
 static unsigned int ip_nat_htable_size;
 
 static struct list_head *bysource;
+
+#define MAX_IP_NAT_PROTO 256
 struct ip_nat_protocol *ip_nat_protos[MAX_IP_NAT_PROTO];
 
+static inline struct ip_nat_protocol *
+__ip_nat_proto_find(u_int8_t protonum)
+{
+	return ip_nat_protos[protonum];
+}
+
+struct ip_nat_protocol *
+ip_nat_proto_find_get(u_int8_t protonum)
+{
+	struct ip_nat_protocol *p;
+
+	/* we need to disable preemption to make sure 'p' doesn't get
+	 * removed until we've grabbed the reference */
+	preempt_disable();
+	p = __ip_nat_proto_find(protonum);
+	if (p) {
+		if (!try_module_get(p->me))
+			p = &ip_nat_unknown_protocol;
+	}
+	preempt_enable();
+
+	return p;
+}
+
+void
+ip_nat_proto_put(struct ip_nat_protocol *p)
+{
+	module_put(p->me);
+}
 
 /* We keep an extra hash for each conntrack, for fast searching. */
 static inline unsigned int
@@ -103,7 +134,8 @@ static int
 in_range(const struct ip_conntrack_tuple *tuple,
 	 const struct ip_nat_range *range)
 {
-	struct ip_nat_protocol *proto = ip_nat_find_proto(tuple->dst.protonum);
+	struct ip_nat_protocol *proto = 
+				__ip_nat_proto_find(tuple->dst.protonum);
 
 	/* If we are supposed to map IPs, then we must be in the
 	   range specified, otherwise let this drag us onto a new src IP. */
@@ -216,8 +248,7 @@ get_unique_tuple(struct ip_conntrack_tuple *tuple,
 		 struct ip_conntrack *conntrack,
 		 enum ip_nat_manip_type maniptype)
 {
-	struct ip_nat_protocol *proto
-		= ip_nat_find_proto(orig_tuple->dst.protonum);
+	struct ip_nat_protocol *proto;
 
 	/* 1) If this srcip/proto/src-proto-part is currently mapped,
 	   and that same mapping gives a unique tuple within the given
@@ -242,14 +273,20 @@ get_unique_tuple(struct ip_conntrack_tuple *tuple,
 	/* 3) The per-protocol part of the manip is made to map into
 	   the range to make a unique tuple. */
 
+	proto = ip_nat_proto_find_get(orig_tuple->dst.protonum);
+
 	/* Only bother mapping if it's not already in range and unique */
 	if ((!(range->flags & IP_NAT_RANGE_PROTO_SPECIFIED)
 	     || proto->in_range(tuple, maniptype, &range->min, &range->max))
-	    && !ip_nat_used_tuple(tuple, conntrack))
+	    && !ip_nat_used_tuple(tuple, conntrack)) {
+		ip_nat_proto_put(proto);
 		return;
+	}
 
 	/* Last change: get protocol to try to obtain unique tuple. */
 	proto->unique_tuple(tuple, range, maniptype, conntrack);
+
+	ip_nat_proto_put(proto);
 }
 
 unsigned int
@@ -320,6 +357,7 @@ manip_pkt(u_int16_t proto,
 	  enum ip_nat_manip_type maniptype)
 {
 	struct iphdr *iph;
+	struct ip_nat_protocol *p;
 
 	if (!skb_ip_make_writable(pskb, iphdroff + sizeof(*iph)))
 		return 0;
@@ -327,9 +365,12 @@ manip_pkt(u_int16_t proto,
 	iph = (void *)(*pskb)->data + iphdroff;
 
 	/* Manipulate protcol part. */
-	if (!ip_nat_find_proto(proto)->manip_pkt(pskb, iphdroff,
-	                                         target, maniptype))
+	p = ip_nat_proto_find_get(proto);
+	if (!p->manip_pkt(pskb, iphdroff, target, maniptype)) {
+		ip_nat_proto_put(p);
 		return 0;
+	}
+	ip_nat_proto_put(p);
 
 	iph = (void *)(*pskb)->data + iphdroff;
 
@@ -425,7 +466,8 @@ int icmp_reply_translation(struct sk_buff **pskb,
 
 	if (!ip_ct_get_tuple(&inside->ip, *pskb, (*pskb)->nh.iph->ihl*4 +
 	                     sizeof(struct icmphdr) + inside->ip.ihl*4,
-	                     &inner, ip_ct_find_proto(inside->ip.protocol)))
+	                     &inner,
+			     __ip_conntrack_proto_find(inside->ip.protocol)))
 		return 0;
 
 	/* Change inner back to look like incoming packet.  We do the
@@ -495,6 +537,49 @@ void ip_nat_protocol_unregister(struct ip_nat_protocol *proto)
 	synchronize_net();
 }
 
+#if defined(CONFIG_IP_NF_CONNTRACK_NETLINK) || \
+    defined(CONFIG_IP_NF_CONNTRACK_NETLINK_MODULE)
+int
+ip_nat_port_range_to_nfattr(struct sk_buff *skb, 
+			    const struct ip_nat_range *range)
+{
+	NFA_PUT(skb, CTA_PROTONAT_PORT_MIN, sizeof(u_int16_t),
+		&range->min.tcp.port);
+	NFA_PUT(skb, CTA_PROTONAT_PORT_MAX, sizeof(u_int16_t),
+		&range->max.tcp.port);
+
+	return 0;
+
+nfattr_failure:
+	return -1;
+}
+
+int
+ip_nat_port_nfattr_to_range(struct nfattr *tb[], struct ip_nat_range *range)
+{
+	int ret = 0;
+	
+	/* we have to return whether we actually parsed something or not */
+
+	if (tb[CTA_PROTONAT_PORT_MIN-1]) {
+		ret = 1;
+		range->min.tcp.port = 
+			*(u_int16_t *)NFA_DATA(tb[CTA_PROTONAT_PORT_MIN-1]);
+	}
+	
+	if (!tb[CTA_PROTONAT_PORT_MAX-1]) {
+		if (ret) 
+			range->max.tcp.port = range->min.tcp.port;
+	} else {
+		ret = 1;
+		range->max.tcp.port = 
+			*(u_int16_t *)NFA_DATA(tb[CTA_PROTONAT_PORT_MAX-1]);
+	}
+
+	return ret;
+}
+#endif
+
 int __init ip_nat_init(void)
 {
 	size_t i;