cfg80211/nl80211: Optional authentication offload to userspace

This interface allows the host driver to offload the authentication to
user space. This is exclusively defined for host drivers that do not
define separate commands for authentication and association, but rely on
userspace SME (e.g., in wpa_supplicant for the ~WPA_DRIVER_FLAGS_SME
case) for the authentication to happen. This can be used to implement
SAE without full implementation in the kernel/firmware while still being
able to use NL80211_CMD_CONNECT with driver-based BSS selection.

Host driver sends NL80211_CMD_EXTERNAL_AUTH event to start/abort
authentication to the port on which connect is triggered and status
of authentication is further indicated by user space to host
driver through the same command response interface.

User space entities advertise this capability through the
NL80211_ATTR_EXTERNAL_AUTH_SUPP flag in the NL80211_CMD_CONNECT request.
Host drivers shall look at this capability to offload the authentication.

Signed-off-by: Srinivas Dasari <dasaris@qti.qualcomm.com>
Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>
[add socket connection ownership check]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

1 files changed, 47 insertions, 0 deletions

diff --git a/include/uapi/linux/nl80211.h b/include/uapi/linux/nl80211.h
index 6f60503fa617..c2342456cf16 100644
--- a/include/uapi/linux/nl80211.h
+++ b/include/uapi/linux/nl80211.h
@@ -992,6 +992,27 @@
  *
  * @NL80211_CMD_RELOAD_REGDB: Request that the regdb firmware file is reloaded.
  *
+ * @NL80211_CMD_EXTERNAL_AUTH: This interface is exclusively defined for host
+ *	drivers that do not define separate commands for authentication and
+ *	association, but rely on user space for the authentication to happen.
+ *	This interface acts both as the event request (driver to user space)
+ *	to trigger the authentication and command response (userspace to
+ *	driver) to indicate the authentication status.
+ *
+ *	User space uses the %NL80211_CMD_CONNECT command to the host driver to
+ *	trigger a connection. The host driver selects a BSS and further uses
+ *	this interface to offload only the authentication part to the user
+ *	space. Authentication frames are passed between the driver and user
+ *	space through the %NL80211_CMD_FRAME interface. Host driver proceeds
+ *	further with the association after getting successful authentication
+ *	status. User space indicates the authentication status through
+ *	%NL80211_ATTR_STATUS_CODE attribute in %NL80211_CMD_EXTERNAL_AUTH
+ *	command interface.
+ *
+ *	Host driver reports this status on an authentication failure to the
+ *	user space through the connect result as the user space would have
+ *	initiated the connection through the connect request.
+ *
  * @NL80211_CMD_MAX: highest used command number
  * @__NL80211_CMD_AFTER_LAST: internal use
  */
@@ -1198,6 +1219,8 @@ enum nl80211_commands {
 
 	NL80211_CMD_RELOAD_REGDB,
 
+	NL80211_CMD_EXTERNAL_AUTH,
+
 	/* add new commands above here */
 
 	/* used to define NL80211_CMD_MAX below */
@@ -2153,6 +2176,16 @@ enum nl80211_commands {
  * @NL80211_ATTR_PMKR0_NAME: PMK-R0 Name for offloaded FT.
  * @NL80211_ATTR_PORT_AUTHORIZED: (reserved)
  *
+ * @NL80211_ATTR_EXTERNAL_AUTH_ACTION: Identify the requested external
+ *     authentication operation (u32 attribute with an
+ *     &enum nl80211_external_auth_action value). This is used with the
+ *     &NL80211_CMD_EXTERNAL_AUTH request event.
+ * @NL80211_ATTR_EXTERNAL_AUTH_SUPPORT: Flag attribute indicating that the user
+ *     space supports external authentication. This attribute shall be used
+ *     only with %NL80211_CMD_CONNECT request. The driver may offload
+ *     authentication processing to user space if this capability is indicated
+ *     in NL80211_CMD_CONNECT requests from the user space.
+ *
  * @NUM_NL80211_ATTR: total number of nl80211_attrs available
  * @NL80211_ATTR_MAX: highest attribute number currently defined
  * @__NL80211_ATTR_AFTER_LAST: internal use
@@ -2579,6 +2612,9 @@ enum nl80211_attrs {
 	NL80211_ATTR_PMKR0_NAME,
 	NL80211_ATTR_PORT_AUTHORIZED,
 
+	NL80211_ATTR_EXTERNAL_AUTH_ACTION,
+	NL80211_ATTR_EXTERNAL_AUTH_SUPPORT,
+
 	/* add attributes here, update the policy in nl80211.c */
 
 	__NL80211_ATTR_AFTER_LAST,
@@ -5495,4 +5531,15 @@ enum nl80211_nan_match_attributes {
 	NL80211_NAN_MATCH_ATTR_MAX = NUM_NL80211_NAN_MATCH_ATTR - 1
 };
 
+/**
+ * nl80211_external_auth_action - Action to perform with external
+ *     authentication request. Used by NL80211_ATTR_EXTERNAL_AUTH_ACTION.
+ * @NL80211_EXTERNAL_AUTH_START: Start the authentication.
+ * @NL80211_EXTERNAL_AUTH_ABORT: Abort the ongoing authentication.
+ */
+enum nl80211_external_auth_action {
+	NL80211_EXTERNAL_AUTH_START,
+	NL80211_EXTERNAL_AUTH_ABORT,
+};
+
 #endif /* __LINUX_NL80211_H */