[NET]: Device name changing via rtnetlink

Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/linux/netdevice.h

@@ -677,6 +677,7 @@ extern int		dev_ioctl(unsigned int cmd, void __user *);
 extern int		dev_ethtool(struct ifreq *);
 extern unsigned		dev_get_flags(const struct net_device *);
 extern int		dev_change_flags(struct net_device *, unsigned);
+extern int		dev_change_name(struct net_device *, char *);
 extern int		dev_set_mtu(struct net_device *, int);
 extern void		dev_queue_xmit_nit(struct sk_buff *skb, struct net_device *dev);
 

net/core/dev.c

@@ -3347,6 +3347,7 @@ EXPORT_SYMBOL(dev_remove_pack);
 EXPORT_SYMBOL(dev_set_allmulti);
 EXPORT_SYMBOL(dev_set_promiscuity);
 EXPORT_SYMBOL(dev_change_flags);
+EXPORT_SYMBOL(dev_change_name);
 EXPORT_SYMBOL(dev_set_mtu);
 EXPORT_SYMBOL(free_netdev);
 EXPORT_SYMBOL(netdev_boot_setup_check);

net/core/rtnetlink.c

@@ -345,6 +345,23 @@ static int do_setlink(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
 		dev->weight = *((u32 *) RTA_DATA(ida[IFLA_WEIGHT - 1]));
 	}
 
+	if (ida[IFLA_IFNAME - 1]) {
+		char ifname[IFNAMSIZ];
+
+		if (ida[IFLA_IFNAME - 1]->rta_len > RTA_LENGTH(sizeof(ifname)))
+			goto out;
+
+		memset(ifname, 0, sizeof(ifname));
+		memcpy(ifname, RTA_DATA(ida[IFLA_IFNAME - 1]),
+			RTA_PAYLOAD(ida[IFLA_IFNAME - 1]));
+		ifname[IFNAMSIZ - 1] = '\0';
+
+		err = dev_change_name(dev, ifname);
+
+		if (err)
+			goto out;
+	}
+
 	err = 0;
 
 out: