cfg80211: allow including station info in delete event

When a station is removed, its statistics may be interesting to
userspace, for example for further aggregation of statistics of
all stations that ever connected to an AP.

Introduce a new cfg80211_del_sta_sinfo() function (and make the
cfg80211_del_sta() a static inline calling it) to allow passing
a struct station_info along with this, and send the data in the
nl80211 event message.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>

diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index f94f0d4..42e3d74 100644 (file)
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -4591,6 +4591,16 @@ void cfg80211_remain_on_channel_expired(struct wireless_dev *wdev, u64 cookie,
 void cfg80211_new_sta(struct net_device *dev, const u8 *mac_addr,
                      struct station_info *sinfo, gfp_t gfp);
 
+/**
+ * cfg80211_del_sta_sinfo - notify userspace about deletion of a station
+ * @dev: the netdev
+ * @mac_addr: the station's address
+ * @sinfo: the station information/statistics
+ * @gfp: allocation flags
+ */
+void cfg80211_del_sta_sinfo(struct net_device *dev, const u8 *mac_addr,
+                           struct station_info *sinfo, gfp_t gfp);
+
 /**
  * cfg80211_del_sta - notify userspace about deletion of a station
  *
@@ -4598,7 +4608,11 @@ void cfg80211_new_sta(struct net_device *dev, const u8 *mac_addr,
  * @mac_addr: the station's address
  * @gfp: allocation flags
  */
-void cfg80211_del_sta(struct net_device *dev, const u8 *mac_addr, gfp_t gfp);
+static inline void cfg80211_del_sta(struct net_device *dev,
+                                   const u8 *mac_addr, gfp_t gfp)
+{
+       cfg80211_del_sta_sinfo(dev, mac_addr, NULL, gfp);
+}
 
 /**
  * cfg80211_conn_failed - connection request failed notification

diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index f56309b..a75dc91 100644 (file)
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -3650,8 +3650,8 @@ static bool nl80211_put_signal(struct sk_buff *msg, u8 mask, s8 *signal,
        return true;
 }
 
-static int nl80211_send_station(struct sk_buff *msg, u32 portid, u32 seq,
-                               int flags,
+static int nl80211_send_station(struct sk_buff *msg, u32 cmd, u32 portid,
+                               u32 seq, int flags,
                                struct cfg80211_registered_device *rdev,
                                struct net_device *dev,
                                const u8 *mac_addr, struct station_info *sinfo)
@@ -3659,7 +3659,7 @@ static int nl80211_send_station(struct sk_buff *msg, u32 portid, u32 seq,
        void *hdr;
        struct nlattr *sinfoattr, *bss_param;
 
-       hdr = nl80211hdr_put(msg, portid, seq, flags, NL80211_CMD_NEW_STATION);
+       hdr = nl80211hdr_put(msg, portid, seq, flags, cmd);
        if (!hdr)
                return -1;
 
@@ -3854,7 +3854,7 @@ static int nl80211_dump_station(struct sk_buff *skb,
                if (err)
                        goto out_err;
 
-               if (nl80211_send_station(skb,
+               if (nl80211_send_station(skb, NL80211_CMD_NEW_STATION,
                                NETLINK_CB(cb->skb).portid,
                                cb->nlh->nlmsg_seq, NLM_F_MULTI,
                                rdev, wdev->netdev, mac_addr,
@@ -3901,7 +3901,8 @@ static int nl80211_get_station(struct sk_buff *skb, struct genl_info *info)
        if (!msg)
                return -ENOMEM;
 
-       if (nl80211_send_station(msg, info->snd_portid, info->snd_seq, 0,
+       if (nl80211_send_station(msg, NL80211_CMD_NEW_STATION,
+                                info->snd_portid, info->snd_seq, 0,
                                 rdev, dev, mac_addr, &sinfo) < 0) {
                nlmsg_free(msg);
                return -ENOBUFS;
@@ -11687,7 +11688,7 @@ void cfg80211_new_sta(struct net_device *dev, const u8 *mac_addr,
        if (!msg)
                return;
 
-       if (nl80211_send_station(msg, 0, 0, 0,
+       if (nl80211_send_station(msg, NL80211_CMD_NEW_STATION, 0, 0, 0,
                                 rdev, dev, mac_addr, sinfo) < 0) {
                nlmsg_free(msg);
                return;
@@ -11698,12 +11699,16 @@ void cfg80211_new_sta(struct net_device *dev, const u8 *mac_addr,
 }
 EXPORT_SYMBOL(cfg80211_new_sta);
 
-void cfg80211_del_sta(struct net_device *dev, const u8 *mac_addr, gfp_t gfp)
+void cfg80211_del_sta_sinfo(struct net_device *dev, const u8 *mac_addr,
+                           struct station_info *sinfo, gfp_t gfp)
 {
        struct wiphy *wiphy = dev->ieee80211_ptr->wiphy;
        struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
        struct sk_buff *msg;
-       void *hdr;
+       struct station_info empty_sinfo = {};
+
+       if (!sinfo)
+               sinfo = &empty_sinfo;
 
        trace_cfg80211_del_sta(dev, mac_addr);
 
@@ -11711,27 +11716,16 @@ void cfg80211_del_sta(struct net_device *dev, const u8 *mac_addr, gfp_t gfp)
        if (!msg)
                return;
 
-       hdr = nl80211hdr_put(msg, 0, 0, 0, NL80211_CMD_DEL_STATION);
-       if (!hdr) {
+       if (nl80211_send_station(msg, NL80211_CMD_DEL_STATION, 0, 0, 0,
+                                rdev, dev, mac_addr, sinfo)) {
                nlmsg_free(msg);
                return;
        }
 
-       if (nla_put_u32(msg, NL80211_ATTR_IFINDEX, dev->ifindex) ||
-           nla_put(msg, NL80211_ATTR_MAC, ETH_ALEN, mac_addr))
-               goto nla_put_failure;
-
-       genlmsg_end(msg, hdr);
-
        genlmsg_multicast_netns(&nl80211_fam, wiphy_net(&rdev->wiphy), msg, 0,
                                NL80211_MCGRP_MLME, gfp);
-       return;
-
- nla_put_failure:
-       genlmsg_cancel(msg, hdr);
-       nlmsg_free(msg);
 }
-EXPORT_SYMBOL(cfg80211_del_sta);
+EXPORT_SYMBOL(cfg80211_del_sta_sinfo);
 
 void cfg80211_conn_failed(struct net_device *dev, const u8 *mac_addr,
                          enum nl80211_connect_failed_reason reason,