nl80211: Event notifications for MLME events

Add new nl80211 event notifications (and a new multicast group, "mlme")
for informing user space about received and processed Authentication,
(Re)Association Response, Deauthentication, and Disassociation frames in
station and IBSS modes (i.e., MLME SAP interface primitives
MLME-AUTHENTICATE.confirm, MLME-ASSOCIATE.confirm,
MLME-REASSOCIATE.confirm, MLME-DEAUTHENTICATE.indicate, and
MLME-DISASSOCIATE.indication). The event data is encapsulated as the 802.11
management frame since we already have the frame in that format and it
includes all the needed information.

This is the initial step in providing MLME SAP interface for
authentication and association with nl80211. In other words, kernel code
will act as the MLME and a user space application can control it as the
SME.

Signed-off-by: Jouni Malinen <j@w1.fi>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 72 insertions, 0 deletions

diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index a3ecf8d73898..c034c2418cb3 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -2830,6 +2830,9 @@ static struct genl_ops nl80211_ops[] = {
                 .dumpit = nl80211_dump_scan,
         },
 };
+static struct genl_multicast_group nl80211_mlme_mcgrp = {
+        .name = "mlme",
+};
 
 /* multicast groups */
 static struct genl_multicast_group nl80211_config_mcgrp = {
@@ -2975,6 +2978,71 @@ nla_put_failure:
         nlmsg_free(msg);
 }
 
+static void nl80211_send_mlme_event(struct cfg80211_registered_device *rdev,
+                                    struct net_device *netdev,
+                                    const u8 *buf, size_t len,
+                                    enum nl80211_commands cmd)
+{
+        struct sk_buff *msg;
+        void *hdr;
+
+        msg = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
+        if (!msg)
+                return;
+
+        hdr = nl80211hdr_put(msg, 0, 0, 0, cmd);
+        if (!hdr) {
+                nlmsg_free(msg);
+                return;
+        }
+
+        NLA_PUT_U32(msg, NL80211_ATTR_WIPHY, rdev->wiphy_idx);
+        NLA_PUT_U32(msg, NL80211_ATTR_IFINDEX, netdev->ifindex);
+        NLA_PUT(msg, NL80211_ATTR_FRAME, len, buf);
+
+        if (genlmsg_end(msg, hdr) < 0) {
+                nlmsg_free(msg);
+                return;
+        }
+
+        genlmsg_multicast(msg, 0, nl80211_mlme_mcgrp.id, GFP_KERNEL);
+        return;
+
+ nla_put_failure:
+        genlmsg_cancel(msg, hdr);
+        nlmsg_free(msg);
+}
+
+void nl80211_send_rx_auth(struct cfg80211_registered_device *rdev,
+                          struct net_device *netdev, const u8 *buf, size_t len)
+{
+        nl80211_send_mlme_event(rdev, netdev, buf, len,
+                                NL80211_CMD_AUTHENTICATE);
+}
+
+void nl80211_send_rx_assoc(struct cfg80211_registered_device *rdev,
+                           struct net_device *netdev, const u8 *buf,
+                           size_t len)
+{
+        nl80211_send_mlme_event(rdev, netdev, buf, len, NL80211_CMD_ASSOCIATE);
+}
+
+void nl80211_send_rx_deauth(struct cfg80211_registered_device *rdev,
+                            struct net_device *netdev, const u8 *buf,
+                            size_t len)
+{
+        nl80211_send_mlme_event(rdev, netdev, buf, len,
+                                NL80211_CMD_DEAUTHENTICATE);
+}
+
+void nl80211_send_rx_disassoc(struct cfg80211_registered_device *rdev,
+                              struct net_device *netdev, const u8 *buf,
+                              size_t len)
+{
+        nl80211_send_mlme_event(rdev, netdev, buf, len,
+                                NL80211_CMD_DISASSOCIATE);
+}
+
 /* initialisation/exit functions */
 
 int nl80211_init(void)
@@ -3003,6 +3071,10 @@ int nl80211_init(void)
         if (err)
                 goto err_out;
 
+        err = genl_register_mc_group(&nl80211_fam, &nl80211_mlme_mcgrp);
+        if (err)
+                goto err_out;
+
         return 0;
  err_out:
         genl_unregister_family(&nl80211_fam);