cfg80211/nl80211: implement station attribute retrieval

After a station is added to the kernel's structures, userspace
has to be able to retrieve statistics about that station, especially
whether the station was idle and how much bytes were transferred
to and from it. This adds the necessary code to nl80211.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 81 insertions, 1 deletions

diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 431835126e88..e3a214f63f91 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -750,9 +750,89 @@ static int parse_station_flags(struct nlattr *nla, u32 *staflags)
         return 0;
 }
 
+static int nl80211_send_station(struct sk_buff *msg, u32 pid, u32 seq,
+                                int flags, struct net_device *dev,
+                                u8 *mac_addr, struct station_stats *stats)
+{
+        void *hdr;
+        struct nlattr *statsattr;
+
+        hdr = nl80211hdr_put(msg, pid, seq, flags, NL80211_CMD_NEW_STATION);
+        if (!hdr)
+                return -1;
+
+        NLA_PUT_U32(msg, NL80211_ATTR_IFINDEX, dev->ifindex);
+        NLA_PUT(msg, NL80211_ATTR_MAC, ETH_ALEN, mac_addr);
+
+        statsattr = nla_nest_start(msg, NL80211_ATTR_STA_STATS);
+        if (!statsattr)
+                goto nla_put_failure;
+        if (stats->filled & STATION_STAT_INACTIVE_TIME)
+                NLA_PUT_U32(msg, NL80211_STA_STAT_INACTIVE_TIME,
+                            stats->inactive_time);
+        if (stats->filled & STATION_STAT_RX_BYTES)
+                NLA_PUT_U32(msg, NL80211_STA_STAT_RX_BYTES,
+                            stats->rx_bytes);
+        if (stats->filled & STATION_STAT_TX_BYTES)
+                NLA_PUT_U32(msg, NL80211_STA_STAT_TX_BYTES,
+                            stats->tx_bytes);
+
+        nla_nest_end(msg, statsattr);
+
+        return genlmsg_end(msg, hdr);
+
+ nla_put_failure:
+        return genlmsg_cancel(msg, hdr);
+}
+
+
 static int nl80211_get_station(struct sk_buff *skb, struct genl_info *info)
 {
-        return -EOPNOTSUPP;
+        struct cfg80211_registered_device *drv;
+        int err;
+        struct net_device *dev;
+        struct station_stats stats;
+        struct sk_buff *msg;
+        u8 *mac_addr = NULL;
+
+        memset(&stats, 0, sizeof(stats));
+
+        if (!info->attrs[NL80211_ATTR_MAC])
+                return -EINVAL;
+
+        mac_addr = nla_data(info->attrs[NL80211_ATTR_MAC]);
+
+        err = get_drv_dev_by_info_ifindex(info, &drv, &dev);
+        if (err)
+                return err;
+
+        if (!drv->ops->get_station) {
+                err = -EOPNOTSUPP;
+                goto out;
+        }
+
+        rtnl_lock();
+        err = drv->ops->get_station(&drv->wiphy, dev, mac_addr, &stats);
+        rtnl_unlock();
+
+        msg = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
+        if (!msg)
+                goto out;
+
+        if (nl80211_send_station(msg, info->snd_pid, info->snd_seq, 0,
+                                 dev, mac_addr, &stats) < 0)
+                goto out_free;
+
+        err = genlmsg_unicast(msg, info->snd_pid);
+        goto out;
+
+ out_free:
+        nlmsg_free(msg);
+
+ out:
+        cfg80211_put_dev(drv);
+        dev_put(dev);
+        return err;
 }
 
 /*