Implemented change command

1 files changed, 83 insertions, 17 deletions

diff --git a/quicktun.c b/quicktun.c
index 0d259c4..2887942 100644
--- a/quicktun.c
+++ b/quicktun.c
@@ -17,7 +17,7 @@
 
 
 #define DRV_NAME	"quicktun"
-#define DRV_VERSION	"0.1"
+#define DRV_VERSION	"1.0"
 #define DRV_DESCRIPTION	"Quicktun tunnel driver"
 
 #define QUICKTUN_MODE_MASK		0x000f
@@ -416,7 +416,6 @@ static struct genl_family quicktun_nl_family = {
 
 static int quicktun_cmd_create_device(struct sk_buff *skb, struct genl_info *info)
 {
-	unsigned long flags = 0;
 	__u16 type = 0;
 	struct quicktun_struct *tun;
 	struct net *net = genl_info_net(info);
@@ -430,14 +429,8 @@ static int quicktun_cmd_create_device(struct sk_buff *skb, struct genl_info *inf
 	if (info->attrs[QUICKTUN_A_MODE])
 		type = nla_get_u16(info->attrs[QUICKTUN_A_MODE]);
 
-	switch (type) {
-	case QUICKTUN_MODE_ETHERNET:
-	case QUICKTUN_MODE_IP:
-		flags |= type;
-		break;
-	default:
+	if (type != QUICKTUN_MODE_ETHERNET && type != QUICKTUN_MODE_IP)
 		return -EINVAL;
-	}
 
 	if (info->attrs[QUICKTUN_A_IFNAME])
 		name = nla_data(info->attrs[QUICKTUN_A_IFNAME]);
@@ -451,7 +444,7 @@ static int quicktun_cmd_create_device(struct sk_buff *skb, struct genl_info *inf
 
 	tun = netdev_priv(dev);
 	tun->dev = dev;
-	tun->flags = flags;
+	tun->flags = type;
 
 	tun->remote_address = kmalloc(sizeof(struct addr_struct), GFP_KERNEL);
 	if (!tun->remote_address) {
@@ -479,10 +472,8 @@ static int quicktun_cmd_create_device(struct sk_buff *skb, struct genl_info *inf
 		tun->remote_address->addr.sin_port = nla_get_be16(info->attrs[QUICKTUN_A_REMOTE_PORT]);
 
 	if (info->attrs[QUICKTUN_A_REMOTE_FLOAT]) {
-		if(nla_get_flag(info->attrs[QUICKTUN_A_REMOTE_FLOAT]))
+		if(nla_get_u8(info->attrs[QUICKTUN_A_REMOTE_FLOAT]))
 			tun->flags |= QUICKTUN_FLAG_REMOTE_FLOAT;
-		else
-			tun->flags &= ~QUICKTUN_FLAG_REMOTE_FLOAT;
 	}
 
 	err = quicktun_socket_init(dev);
@@ -570,6 +561,78 @@ err_unlock:
 	return err;
 }
 
+static int quicktun_cmd_change_device(struct sk_buff *skb, struct genl_info *info)
+{
+	int err;
+	struct net *net = genl_info_net(info);
+	struct addr_struct *old_addr, *addr;
+	struct net_device *dev;
+	struct quicktun_struct *tun;
+	char *name;
+
+	if (!capable(CAP_NET_ADMIN))
+		return -EPERM;
+
+	if (!info->attrs[QUICKTUN_A_IFNAME])
+		return -EINVAL;
+
+	name = nla_data(info->attrs[QUICKTUN_A_IFNAME]);
+
+	rtnl_lock();
+
+	dev = __dev_get_by_name(net, name);
+	if (!dev) {
+		err = -EINVAL;
+		goto err_unlock;
+	}
+
+	if (dev->netdev_ops != &quicktun_ethernet_netdev_ops && dev->netdev_ops != &quicktun_ip_netdev_ops) {
+		err = -EINVAL;
+		goto err_unlock;
+	}
+
+	tun = netdev_priv(dev);
+
+	addr = kmalloc(sizeof(struct addr_struct), GFP_KERNEL);
+	if (!addr) {
+		err = -ENOMEM;
+		goto err_unlock;
+	}
+
+	spin_lock(&tun->lock);
+
+	old_addr = rcu_dereference_protected(tun->remote_address, lockdep_is_held(&tun->lock));
+
+	addr->addr = old_addr->addr;
+
+	if (info->attrs[QUICKTUN_A_REMOTE_ADDRESS])
+		addr->addr.sin_addr.s_addr = nla_get_be32(info->attrs[QUICKTUN_A_REMOTE_ADDRESS]);
+
+	if (info->attrs[QUICKTUN_A_REMOTE_PORT])
+		addr->addr.sin_port = nla_get_be16(info->attrs[QUICKTUN_A_REMOTE_PORT]);
+
+	if (info->attrs[QUICKTUN_A_REMOTE_FLOAT]) {
+		if(nla_get_u8(info->attrs[QUICKTUN_A_REMOTE_FLOAT]))
+			tun->flags |= QUICKTUN_FLAG_REMOTE_FLOAT;
+		else
+			tun->flags &= ~QUICKTUN_FLAG_REMOTE_FLOAT;
+	}
+
+	rcu_assign_pointer(tun->remote_address, addr);
+	call_rcu(&old_addr->rcu, free_addr_struct);
+
+	spin_unlock(&tun->lock);
+
+	rtnl_unlock();
+
+	return 0;
+
+err_unlock:
+	rtnl_unlock();
+
+	return err;
+}
+
 static void __put_tunnel_spec(struct sk_buff *skb, struct quicktun_struct *tun)
 {
 	struct nlattr *nested = nla_nest_start(skb, QUICKTUN_A_TUNNEL_SPEC);
@@ -585,9 +648,7 @@ static void __put_tunnel_spec(struct sk_buff *skb, struct quicktun_struct *tun)
 	nla_put_u16(skb, QUICKTUN_A_LOCAL_PORT, tun->local_address.sin_port);
 	nla_put_u32(skb, QUICKTUN_A_REMOTE_ADDRESS, remote_addr->addr.sin_addr.s_addr);
 	nla_put_u16(skb, QUICKTUN_A_REMOTE_PORT, remote_addr->addr.sin_port);
-
-	if (tun->flags & QUICKTUN_FLAG_REMOTE_FLOAT)
-		nla_put_flag(skb, QUICKTUN_A_REMOTE_FLOAT);
+	nla_put_u8(skb, QUICKTUN_A_REMOTE_FLOAT, (tun->flags & QUICKTUN_FLAG_REMOTE_FLOAT) ? 1 : 0);
 
 	rcu_read_unlock();
 
@@ -658,7 +719,7 @@ static struct nla_policy quicktun_nl_policy[__QUICKTUN_A_MAX] = {
 	[QUICKTUN_A_LOCAL_PORT]		= { .type = NLA_U16 },
 	[QUICKTUN_A_REMOTE_ADDRESS]	= { .type = NLA_U32 },
 	[QUICKTUN_A_REMOTE_PORT]	= { .type = NLA_U16 },
-	[QUICKTUN_A_REMOTE_FLOAT]	= { .type = NLA_FLAG },
+	[QUICKTUN_A_REMOTE_FLOAT]	= { .type = NLA_U8 },
 };
 
 static struct genl_ops quicktun_nl_ops[] = {
@@ -673,6 +734,11 @@ static struct genl_ops quicktun_nl_ops[] = {
 		.policy = quicktun_nl_policy,
 	},
 	{
+		.cmd = QUICKTUN_CMD_CHANGE_DEVICE,
+		.doit = quicktun_cmd_change_device,
+		.policy = quicktun_nl_policy,
+	},
+	{
 		.cmd = QUICKTUN_CMD_GET_DEVICE,
 		.doit = quicktun_cmd_get_device,
 		.policy = quicktun_nl_policy,