cfg80211: Allow cfg80211_connect_result() errors to be distinguished

Previously, the status parameter to cfg80211_connect_result() was
documented as using WLAN_STATUS_UNSPECIFIED_FAILURE (1) when the real
status code for the failure is not known. This value can be used by an
AP (and often is) and as such, user space cannot distinguish between
explicitly rejected authentication/association and not being able to
even try to associate or not receiving a response from the AP.

Add a new inline function, cfg80211_connect_timeout(), to be used when
the driver knows that the connection attempt failed due to a reason
where connection could not be attempt or no response was received from
the AP. The internal functions now allow a negative status value (-1) to
be used as an indication of this special case. This results in the
NL80211_ATTR_TIMED_OUT to be added to the NL80211_CMD_CONNECT event to
allow user space to determine this case was hit. For backwards
compatibility, NL80211_STATUS_CODE with the value
WLAN_STATUS_UNSPECIFIED_FAILURE is still indicated in the event in such
a case.

Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>
[johannes: fix cfg80211_connect_bss() prototype to use int for status,
 add cfg80211_connect_timeout() to docbook, fix docbook]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

4 files changed, 11 insertions, 10 deletions

diff --git a/net/wireless/core.h b/net/wireless/core.h
index 025b7a5d508b..a4d547f99f8d 100644
--- a/net/wireless/core.h
+++ b/net/wireless/core.h
@@ -214,7 +214,7 @@ struct cfg80211_event {
                         size_t req_ie_len;
                         size_t resp_ie_len;
                         struct cfg80211_bss *bss;
-                        u16 status;
+                        int status; /* -1 = failed; 0..65535 = status code */
                 } cr;
                 struct {
                         const u8 *req_ie;
@@ -374,7 +374,7 @@ int cfg80211_connect(struct cfg80211_registered_device *rdev,
 void __cfg80211_connect_result(struct net_device *dev, const u8 *bssid,
                                const u8 *req_ie, size_t req_ie_len,
                                const u8 *resp_ie, size_t resp_ie_len,
-                               u16 status, bool wextev,
+                               int status, bool wextev,
                                struct cfg80211_bss *bss);
 void __cfg80211_disconnected(struct net_device *dev, const u8 *ie,
                              size_t ie_len, u16 reason, bool from_ap);
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index bf75afa18699..03ac2ba8b174 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -12092,7 +12092,7 @@ void nl80211_send_connect_result(struct cfg80211_registered_device *rdev,
                                  struct net_device *netdev, const u8 *bssid,
                                  const u8 *req_ie, size_t req_ie_len,
                                  const u8 *resp_ie, size_t resp_ie_len,
-                                 u16 status, gfp_t gfp)
+                                 int status, gfp_t gfp)
 {
         struct sk_buff *msg;
         void *hdr;
@@ -12110,7 +12110,10 @@ void nl80211_send_connect_result(struct cfg80211_registered_device *rdev,
         if (nla_put_u32(msg, NL80211_ATTR_WIPHY, rdev->wiphy_idx) ||
             nla_put_u32(msg, NL80211_ATTR_IFINDEX, netdev->ifindex) ||
             (bssid && nla_put(msg, NL80211_ATTR_MAC, ETH_ALEN, bssid)) ||
-            nla_put_u16(msg, NL80211_ATTR_STATUS_CODE, status) ||
+            nla_put_u16(msg, NL80211_ATTR_STATUS_CODE,
+                        status < 0 ? WLAN_STATUS_UNSPECIFIED_FAILURE :
+                        status) ||
+            (status < 0 && nla_put_flag(msg, NL80211_ATTR_TIMED_OUT)) ||
             (req_ie &&
              nla_put(msg, NL80211_ATTR_REQ_IE, req_ie_len, req_ie)) ||
             (resp_ie &&
diff --git a/net/wireless/nl80211.h b/net/wireless/nl80211.h
index 84d4edf1d545..a63f402b10b7 100644
--- a/net/wireless/nl80211.h
+++ b/net/wireless/nl80211.h
@@ -55,7 +55,7 @@ void nl80211_send_connect_result(struct cfg80211_registered_device *rdev,
                                  struct net_device *netdev, const u8 *bssid,
                                  const u8 *req_ie, size_t req_ie_len,
                                  const u8 *resp_ie, size_t resp_ie_len,
-                                 u16 status, gfp_t gfp);
+                                 int status, gfp_t gfp);
 void nl80211_send_roamed(struct cfg80211_registered_device *rdev,
                          struct net_device *netdev, const u8 *bssid,
                          const u8 *req_ie, size_t req_ie_len,
diff --git a/net/wireless/sme.c b/net/wireless/sme.c
index 584fdc347221..add6824c44fd 100644
--- a/net/wireless/sme.c
+++ b/net/wireless/sme.c
@@ -244,9 +244,7 @@ void cfg80211_conn_work(struct work_struct *work)
                 if (cfg80211_conn_do_work(wdev)) {
                         __cfg80211_connect_result(
                                         wdev->netdev, bssid,
-                                        NULL, 0, NULL, 0,
-                                        WLAN_STATUS_UNSPECIFIED_FAILURE,
-                                        false, NULL);
+                                        NULL, 0, NULL, 0, -1, false, NULL);
                 }
                 wdev_unlock(wdev);
         }
@@ -648,7 +646,7 @@ static DECLARE_WORK(cfg80211_disconnect_work, disconnect_work);
 void __cfg80211_connect_result(struct net_device *dev, const u8 *bssid,
                                const u8 *req_ie, size_t req_ie_len,
                                const u8 *resp_ie, size_t resp_ie_len,
-                               u16 status, bool wextev,
+                               int status, bool wextev,
                                struct cfg80211_bss *bss)
 {
         struct wireless_dev *wdev = dev->ieee80211_ptr;
@@ -757,7 +755,7 @@ void __cfg80211_connect_result(struct net_device *dev, const u8 *bssid,
 void cfg80211_connect_bss(struct net_device *dev, const u8 *bssid,
                           struct cfg80211_bss *bss, const u8 *req_ie,
                           size_t req_ie_len, const u8 *resp_ie,
-                          size_t resp_ie_len, u16 status, gfp_t gfp)
+                          size_t resp_ie_len, int status, gfp_t gfp)
 {
         struct wireless_dev *wdev = dev->ieee80211_ptr;
         struct cfg80211_registered_device *rdev = wiphy_to_rdev(wdev->wiphy);