nf_nat: use secure_ipv4_port_ephemeral() for NAT port randomization

Use incoming network tuple as seed for NAT port randomization.
This avoids concerns of leaking net_random() bits, and also gives better
port distribution. Don't have NAT server, compile tested only.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>

[ added missing EXPORT_SYMBOL_GPL ]

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 1 insertions, 0 deletions

diff --git a/drivers/char/random.c b/drivers/char/random.c
index e0d0e371909c..1838aa3d24fe 100644
--- a/drivers/char/random.c
+++ b/drivers/char/random.c
@@ -1571,6 +1571,7 @@ u32 secure_ipv4_port_ephemeral(__be32 saddr, __be32 daddr, __be16 dport)
 
         return half_md4_transform(hash, keyptr->secret);
 }
+EXPORT_SYMBOL_GPL(secure_ipv4_port_ephemeral);
 
 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 u32 secure_ipv6_port_ephemeral(const __be32 *saddr, const __be32 *daddr,