6 files changed, 77 insertions, 0 deletions

diff --git a/include/linux/if.h b/include/linux/if.h
index 5c9d1fa93fe..65246846c84 100644
--- a/include/linux/if.h
+++ b/include/linux/if.h
@@ -24,6 +24,7 @@
 #include <linux/compiler.h>             /* for "__user" et al           */
 
 #define IFNAMSIZ        16
+#define IFALIASZ        256
 #include <linux/hdlc/ioctl.h>
 
 /* Standard interface flags (netdevice->flags). */
diff --git a/include/linux/if_link.h b/include/linux/if_link.h
index 84c3492ae5c..f9032c88716 100644
--- a/include/linux/if_link.h
+++ b/include/linux/if_link.h
@@ -79,6 +79,7 @@ enum
         IFLA_LINKINFO,
 #define IFLA_LINKINFO IFLA_LINKINFO
         IFLA_NET_NS_PID,
+        IFLA_IFALIAS,
         __IFLA_MAX
 };
 
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 488c56e649b..d675df08b94 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -471,6 +471,8 @@ struct net_device
         char                    name[IFNAMSIZ];
         /* device name hash chain */
         struct hlist_node       name_hlist;
+        /* snmp alias */
+        char                    *ifalias;
 
         /*
          *      I/O specific fields
@@ -1224,6 +1226,7 @@ extern int		dev_ethtool(struct net *net, 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_alias(struct net_device *, const char *, size_t);
 extern int              dev_change_net_namespace(struct net_device *,
                                                  struct net *, const char *);
 extern int              dev_set_mtu(struct net_device *, int);
diff --git a/net/core/dev.c b/net/core/dev.c
index fdfc4b6a644..e9139053399 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -954,6 +954,29 @@ rollback:
 }
 
 /**
+ *      dev_set_alias - change ifalias of a device
+ *      @dev: device
+ *      @alias: name up to IFALIASZ
+ *
+ *      Set ifalias for a device,
+ */
+int dev_set_alias(struct net_device *dev, const char *alias, size_t len)
+{
+        ASSERT_RTNL();
+
+        if (len >= IFALIASZ)
+                return -EINVAL;
+
+        dev->ifalias = krealloc(dev->ifalias, len+1, GFP_KERNEL);
+        if (!dev->ifalias)
+                return -ENOMEM;
+
+        strlcpy(dev->ifalias, alias, len+1);
+        return len;
+}
+
+
+/**
  *      netdev_features_change - device changes features
  *      @dev: device to cause notification
  *
diff --git a/net/core/net-sysfs.c b/net/core/net-sysfs.c
index c1f4e0d428c..92d6b946731 100644
--- a/net/core/net-sysfs.c
+++ b/net/core/net-sysfs.c
@@ -209,9 +209,44 @@ static ssize_t store_tx_queue_len(struct device *dev,
         return netdev_store(dev, attr, buf, len, change_tx_queue_len);
 }
 
+static ssize_t store_ifalias(struct device *dev, struct device_attribute *attr,
+                             const char *buf, size_t len)
+{
+        struct net_device *netdev = to_net_dev(dev);
+        size_t count = len;
+        ssize_t ret;
+
+        if (!capable(CAP_NET_ADMIN))
+                return -EPERM;
+
+        /* ignore trailing newline */
+        if (len >  0 && buf[len - 1] == '\n')
+                --count;
+
+        rtnl_lock();
+        ret = dev_set_alias(netdev, buf, count);
+        rtnl_unlock();
+
+        return ret < 0 ? ret : len;
+}
+
+static ssize_t show_ifalias(struct device *dev,
+                            struct device_attribute *attr, char *buf)
+{
+        const struct net_device *netdev = to_net_dev(dev);
+        ssize_t ret = 0;
+
+        rtnl_lock();
+        if (netdev->ifalias)
+                ret = sprintf(buf, "%s\n", netdev->ifalias);
+        rtnl_unlock();
+        return ret;
+}
+
 static struct device_attribute net_class_attributes[] = {
         __ATTR(addr_len, S_IRUGO, show_addr_len, NULL),
         __ATTR(dev_id, S_IRUGO, show_dev_id, NULL),
+        __ATTR(ifalias, S_IRUGO | S_IWUSR, show_ifalias, store_ifalias),
         __ATTR(iflink, S_IRUGO, show_iflink, NULL),
         __ATTR(ifindex, S_IRUGO, show_ifindex, NULL),
         __ATTR(features, S_IRUGO, show_features, NULL),
@@ -418,6 +453,7 @@ static void netdev_release(struct device *d)
 
         BUG_ON(dev->reg_state != NETREG_RELEASED);
 
+        kfree(dev->ifalias);
         kfree((char *)dev - dev->padded);
 }
 
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index 71edb8b3634..8862498fd4a 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -586,6 +586,7 @@ static inline size_t if_nlmsg_size(const struct net_device *dev)
 {
         return NLMSG_ALIGN(sizeof(struct ifinfomsg))
                + nla_total_size(IFNAMSIZ) /* IFLA_IFNAME */
+               + nla_total_size(IFALIASZ) /* IFLA_IFALIAS */
                + nla_total_size(IFNAMSIZ) /* IFLA_QDISC */
                + nla_total_size(sizeof(struct rtnl_link_ifmap))
                + nla_total_size(sizeof(struct rtnl_link_stats))
@@ -640,6 +641,9 @@ static int rtnl_fill_ifinfo(struct sk_buff *skb, struct net_device *dev,
         if (txq->qdisc_sleeping)
                 NLA_PUT_STRING(skb, IFLA_QDISC, txq->qdisc_sleeping->ops->id);
 
+        if (dev->ifalias)
+                NLA_PUT_STRING(skb, IFLA_IFALIAS, dev->ifalias);
+
         if (1) {
                 struct rtnl_link_ifmap map = {
                         .mem_start   = dev->mem_start,
@@ -713,6 +717,7 @@ const struct nla_policy ifla_policy[IFLA_MAX+1] = {
         [IFLA_LINKMODE]         = { .type = NLA_U8 },
         [IFLA_LINKINFO]         = { .type = NLA_NESTED },
         [IFLA_NET_NS_PID]       = { .type = NLA_U32 },
+        [IFLA_IFALIAS]          = { .type = NLA_STRING, .len = IFALIASZ-1 },
 };
 
 static const struct nla_policy ifla_info_policy[IFLA_INFO_MAX+1] = {
@@ -853,6 +858,14 @@ static int do_setlink(struct net_device *dev, struct ifinfomsg *ifm,
                 modified = 1;
         }
 
+        if (tb[IFLA_IFALIAS]) {
+                err = dev_set_alias(dev, nla_data(tb[IFLA_IFALIAS]),
+                                    nla_len(tb[IFLA_IFALIAS]));
+                if (err < 0)
+                        goto errout;
+                modified = 1;
+        }
+
         if (tb[IFLA_BROADCAST]) {
                 nla_memcpy(dev->broadcast, tb[IFLA_BROADCAST], dev->addr_len);
                 send_addr_notify = 1;