cfg80211: Add local-state-change-only auth/deauth/disassoc

cfg80211 is quite strict on allowing authentication and association
commands only in certain states. In order to meet these requirements,
user space applications may need to clear authentication or
association state in some cases. Currently, this can be done with
deauth/disassoc command, but that ends up sending out Deauthentication
or Disassociation frame unnecessarily. Add a new nl80211 attribute to
allow this sending of the frame be skipped, but with all other
deauth/disassoc operations being completed.

Similar state change is also needed for IEEE 802.11r FT protocol in
the FT-over-DS case which does not use Authentication frame exchange
in a transition to another BSS. For this to work with cfg80211, an
authentication entry needs to be created for the target BSS without
sending out an Authentication frame. The nl80211 authentication
command can be used for this purpose, too, with the new attribute to
indicate that the command is only for changing local state. This
enables wpa_supplicant to complete FT-over-DS transition successfully.

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

2 files changed, 19 insertions, 0 deletions

diff --git a/include/linux/nl80211.h b/include/linux/nl80211.h
index daf6a3432b92..2ea3edeee7aa 100644
--- a/include/linux/nl80211.h
+++ b/include/linux/nl80211.h
@@ -703,6 +703,12 @@ enum nl80211_commands {
  * @NL80211_ATTR_CQM: connection quality monitor configuration in a
  *      nested attribute with %NL80211_ATTR_CQM_* sub-attributes.
  *
+ * @NL80211_ATTR_LOCAL_STATE_CHANGE: Flag attribute to indicate that a command
+ *      is requesting a local authentication/association state change without
+ *      invoking actual management frame exchange. This can be used with
+ *      NL80211_CMD_AUTHENTICATE, NL80211_CMD_DEAUTHENTICATE,
+ *      NL80211_CMD_DISASSOCIATE.
+ *
  * @NL80211_ATTR_MAX: highest attribute number currently defined
  * @__NL80211_ATTR_AFTER_LAST: internal use
  */
@@ -856,6 +862,8 @@ enum nl80211_attrs {
 
         NL80211_ATTR_CQM,
 
+        NL80211_ATTR_LOCAL_STATE_CHANGE,
+
         /* add attributes here, update the policy in nl80211.c */
 
         __NL80211_ATTR_AFTER_LAST,
diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index 868cfd3b9724..37cebd3aa0f7 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -704,6 +704,10 @@ struct cfg80211_crypto_settings {
  * @key_len: length of WEP key for shared key authentication
  * @key_idx: index of WEP key for shared key authentication
  * @key: WEP key for shared key authentication
+ * @local_state_change: This is a request for a local state only, i.e., no
+ *      Authentication frame is to be transmitted and authentication state is
+ *      to be changed without having to wait for a response from the peer STA
+ *      (AP).
  */
 struct cfg80211_auth_request {
         struct cfg80211_bss *bss;
@@ -712,6 +716,7 @@ struct cfg80211_auth_request {
         enum nl80211_auth_type auth_type;
         const u8 *key;
         u8 key_len, key_idx;
+        bool local_state_change;
 };
 
 /**
@@ -744,12 +749,15 @@ struct cfg80211_assoc_request {
  * @ie: Extra IEs to add to Deauthentication frame or %NULL
  * @ie_len: Length of ie buffer in octets
  * @reason_code: The reason code for the deauthentication
+ * @local_state_change: This is a request for a local state only, i.e., no
+ *      Deauthentication frame is to be transmitted.
  */
 struct cfg80211_deauth_request {
         struct cfg80211_bss *bss;
         const u8 *ie;
         size_t ie_len;
         u16 reason_code;
+        bool local_state_change;
 };
 
 /**
@@ -762,12 +770,15 @@ struct cfg80211_deauth_request {
  * @ie: Extra IEs to add to Disassociation frame or %NULL
  * @ie_len: Length of ie buffer in octets
  * @reason_code: The reason code for the disassociation
+ * @local_state_change: This is a request for a local state only, i.e., no
+ *      Disassociation frame is to be transmitted.
  */
 struct cfg80211_disassoc_request {
         struct cfg80211_bss *bss;
         const u8 *ie;
         size_t ie_len;
         u16 reason_code;
+        bool local_state_change;
 };
 
 /**