[NETFILTER]: NAT: optional source port randomization support

This patch adds support to NAT to randomize source ports.

Signed-off-by: Eric Leblond <eric@inl.fr>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 4 insertions, 0 deletions

diff --git a/net/ipv4/netfilter/nf_nat_rule.c b/net/ipv4/netfilter/nf_nat_rule.c
index b868ee0195d..3745efe7030 100644
--- a/net/ipv4/netfilter/nf_nat_rule.c
+++ b/net/ipv4/netfilter/nf_nat_rule.c
@@ -226,6 +226,10 @@ static int ipt_dnat_checkentry(const char *tablename,
                 printk("DNAT: multiple ranges no longer supported\n");
                 return 0;
         }
+        if (mr->range[0].flags & IP_NAT_RANGE_PROTO_RANDOM) {
+                printk("DNAT: port randomization not supported\n");
+                return 0;
+        }
         return 1;
 }