Bind to random port by default (for floating hosts), don't hardcode default port into kernel moduleHEADv1.0master

2 files changed, 14 insertions, 11 deletions

diff --git a/quicktun.c b/quicktun.c
index 1c8a302..24a0d73 100644
--- a/quicktun.c
+++ b/quicktun.c
@@ -81,7 +81,7 @@ static netdev_tx_t quicktun_net_xmit(struct sk_buff *skb, struct net_device *dev
 
 	remote_addr = rcu_dereference(tun->remote_address);
 
-	if (likely(remote_addr->addr.sin_addr.s_addr)) {
+	if (likely(remote_addr->addr.sin_addr.s_addr && remote_addr->addr.sin_port)) {
 		rt = ip_route_output_ports(dev_net(dev), NULL, remote_addr->addr.sin_addr.s_addr, tun->local_address.sin_addr.s_addr,
 					   remote_addr->addr.sin_port, tun->local_address.sin_port, IPPROTO_UDP, 0, 0);
 		if (!rt) {
@@ -354,7 +354,7 @@ static void quicktun_setup(struct net_device *dev)
 
 	tun->local_address.sin_family = AF_INET;
 	tun->local_address.sin_addr.s_addr = 0;
-	tun->local_address.sin_port = htons(QUICKTUN_DEFAULT_PORT);
+	tun->local_address.sin_port = 0;
 
 	dev->ethtool_ops = &quicktun_ethtool_ops;
 }
@@ -393,7 +393,7 @@ static int quicktun_socket_init(struct net_device *dev)
 {
 	int err;
 	struct quicktun_struct *tun = netdev_priv(dev);
-
+	int addrlen;
 
 	err = sock_create_kern(AF_INET, SOCK_DGRAM, 0, &tun->sock);
 	if (err < 0)
@@ -406,6 +406,11 @@ static int quicktun_socket_init(struct net_device *dev)
 	if (err < 0)
 		goto error;
 
+	addrlen = sizeof(tun->local_address);
+	err = kernel_getsockname(tun->sock, (struct sockaddr*)&tun->local_address, &addrlen);
+	if (err < 0)
+		goto error;
+
 	return 0;
 error:
 	sock_release(tun->sock);
@@ -424,7 +429,7 @@ static struct genl_family quicktun_nl_family = {
 
 static int quicktun_cmd_create_device(struct sk_buff *skb, struct genl_info *info)
 {
-	__u16 type = 0;
+	__u16 type;
 	struct quicktun_struct *tun;
 	struct net *net = genl_info_net(info);
 	struct net_device *dev;
@@ -434,9 +439,10 @@ static int quicktun_cmd_create_device(struct sk_buff *skb, struct genl_info *inf
 	if (!capable(CAP_NET_ADMIN))
 		return -EPERM;
 
-	if (info->attrs[QUICKTUN_A_MODE])
-		type = nla_get_u16(info->attrs[QUICKTUN_A_MODE]);
+	if (!info->attrs[QUICKTUN_A_MODE])
+		return -EINVAL;
 
+	type = nla_get_u16(info->attrs[QUICKTUN_A_MODE]);
 	if (type != QUICKTUN_MODE_ETHERNET && type != QUICKTUN_MODE_IP)
 		return -EINVAL;
 
@@ -462,16 +468,15 @@ static int quicktun_cmd_create_device(struct sk_buff *skb, struct genl_info *inf
 
 	tun->remote_address->addr.sin_family = AF_INET;
 	tun->remote_address->addr.sin_addr.s_addr = 0;
-	tun->remote_address->addr.sin_port = htons(QUICKTUN_DEFAULT_PORT);
+	tun->remote_address->addr.sin_port = 0;
 
 	quicktun_net_init(dev);
 	
 	if (info->attrs[QUICKTUN_A_LOCAL_ADDRESS])
 		tun->local_address.sin_addr.s_addr = nla_get_be32(info->attrs[QUICKTUN_A_LOCAL_ADDRESS]);
 
-	/* Set remote port to local port by default */
 	if (info->attrs[QUICKTUN_A_LOCAL_PORT])
-		tun->remote_address->addr.sin_port = tun->local_address.sin_port = nla_get_be16(info->attrs[QUICKTUN_A_LOCAL_PORT]);
+		tun->local_address.sin_port = nla_get_be16(info->attrs[QUICKTUN_A_LOCAL_PORT]);
 
 	if (info->attrs[QUICKTUN_A_REMOTE_ADDRESS])
 		tun->remote_address->addr.sin_addr.s_addr = nla_get_be32(info->attrs[QUICKTUN_A_REMOTE_ADDRESS]);
diff --git a/quicktun.h b/quicktun.h
index e25b657..8280201 100644
--- a/quicktun.h
+++ b/quicktun.h
@@ -44,6 +44,4 @@ enum {
 #define QUICKTUN_CMD_MAX (__QUICKTUN_CMD_MAX - 1)
 #define QUICKTUN_A_MAX (__QUICKTUN_A_MAX - 1)
 
-#define QUICKTUN_DEFAULT_PORT 2998
-
 #endif /* __QUICKTUN_H */