[NETFILTER]: nf_nat: add helpers for common NAT protocol operations

[linux-2.6-omap-h63xx.git] / net / ipv4 / netfilter / nf_nat_proto_tcp.c

diff --git a/net/ipv4/netfilter/nf_nat_proto_tcp.c b/net/ipv4/netfilter/nf_nat_proto_tcp.c
index ffd5d1589eca55bfd167f452ba0a3eb5efc9926a..f8c498fc24fd2a3cd9bde5c2e8ed184968bef7fd 100644 (file)
--- a/net/ipv4/netfilter/nf_nat_proto_tcp.c
+++ b/net/ipv4/netfilter/nf_nat_proto_tcp.c
@@ -8,7 +8,6 @@
 
 #include <linux/types.h>
 #include <linux/init.h>
-#include <linux/random.h>
 #include <linux/ip.h>
 #include <linux/tcp.h>
 
@@ -19,22 +18,7 @@
 #include <net/netfilter/nf_nat_protocol.h>
 #include <net/netfilter/nf_nat_core.h>
 
-static int
-tcp_in_range(const struct nf_conntrack_tuple *tuple,
-            enum nf_nat_manip_type maniptype,
-            const union nf_conntrack_man_proto *min,
-            const union nf_conntrack_man_proto *max)
-{
-       __be16 port;
-
-       if (maniptype == IP_NAT_MANIP_SRC)
-               port = tuple->src.u.tcp.port;
-       else
-               port = tuple->dst.u.tcp.port;
-
-       return ntohs(port) >= ntohs(min->tcp.port) &&
-              ntohs(port) <= ntohs(max->tcp.port);
-}
+static u_int16_t tcp_port_rover;
 
 static int
 tcp_unique_tuple(struct nf_conntrack_tuple *tuple,
@@ -42,49 +26,8 @@ tcp_unique_tuple(struct nf_conntrack_tuple *tuple,
                 enum nf_nat_manip_type maniptype,
                 const struct nf_conn *ct)
 {
-       static u_int16_t port;
-       __be16 *portptr;
-       unsigned int range_size, min, i;
-
-       if (maniptype == IP_NAT_MANIP_SRC)
-               portptr = &tuple->src.u.tcp.port;
-       else
-               portptr = &tuple->dst.u.tcp.port;
-
-       /* If no range specified... */
-       if (!(range->flags & IP_NAT_RANGE_PROTO_SPECIFIED)) {
-               /* If it's dst rewrite, can't change port */
-               if (maniptype == IP_NAT_MANIP_DST)
-                       return 0;
-
-               /* Map privileged onto privileged. */
-               if (ntohs(*portptr) < 1024) {
-                       /* Loose convention: >> 512 is credential passing */
-                       if (ntohs(*portptr)<512) {
-                               min = 1;
-                               range_size = 511 - min + 1;
-                       } else {
-                               min = 600;
-                               range_size = 1023 - min + 1;
-                       }
-               } else {
-                       min = 1024;
-                       range_size = 65535 - 1024 + 1;
-               }
-       } else {
-               min = ntohs(range->min.tcp.port);
-               range_size = ntohs(range->max.tcp.port) - min + 1;
-       }
-
-       if (range->flags & IP_NAT_RANGE_PROTO_RANDOM)
-               port =  net_random();
-
-       for (i = 0; i < range_size; i++, port++) {
-               *portptr = htons(min + port % range_size);
-               if (!nf_nat_used_tuple(tuple, ct))
-                       return 1;
-       }
-       return 0;
+       return nf_nat_proto_unique_tuple(tuple, range, maniptype, ct,
+                                        &tcp_port_rover);
 }
 
 static int
@@ -142,7 +85,7 @@ const struct nf_nat_protocol nf_nat_protocol_tcp = {
        .protonum               = IPPROTO_TCP,
        .me                     = THIS_MODULE,
        .manip_pkt              = tcp_manip_pkt,
-       .in_range               = tcp_in_range,
+       .in_range               = nf_nat_proto_in_range,
        .unique_tuple           = tcp_unique_tuple,
 #if defined(CONFIG_NF_CT_NETLINK) || defined(CONFIG_NF_CT_NETLINK_MODULE)
        .range_to_nlattr        = nf_nat_port_range_to_nlattr,