cfg80211: Add support for FILS shared key authentication offload

Enhance nl80211 and cfg80211 connect request and response APIs to
support FILS shared key authentication offload. The new nl80211
attributes can be used to provide additional information to the driver
to establish a FILS connection. Also enhance the set/del PMKSA to allow
support for adding and deleting PMKSA based on FILS cache identifier.

Add a new feature flag that drivers can use to advertize support for
FILS shared key authentication and association in station mode when
using their own SME.

Signed-off-by: Vidyullatha Kanchanapally <vkanchan@qti.qualcomm.com>
Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

1 files changed, 83 insertions, 3 deletions

diff --git a/include/uapi/linux/nl80211.h b/include/uapi/linux/nl80211.h
index cd4dfef..6095a6c 100644
--- a/include/uapi/linux/nl80211.h
+++ b/include/uapi/linux/nl80211.h
@@ -173,6 +173,42 @@
  */
 
 /**
+ * DOC: FILS shared key authentication offload
+ *
+ * FILS shared key authentication offload can be advertized by drivers by
+ * setting @NL80211_EXT_FEATURE_FILS_SK_OFFLOAD flag. The drivers that support
+ * FILS shared key authentication offload should be able to construct the
+ * authentication and association frames for FILS shared key authentication and
+ * eventually do a key derivation as per IEEE 802.11ai. The below additional
+ * parameters should be given to driver in %NL80211_CMD_CONNECT.
+ *	%NL80211_ATTR_FILS_ERP_USERNAME - used to construct keyname_nai
+ *	%NL80211_ATTR_FILS_ERP_REALM - used to construct keyname_nai
+ *	%NL80211_ATTR_FILS_ERP_NEXT_SEQ_NUM - used to construct erp message
+ *	%NL80211_ATTR_FILS_ERP_RRK - used to generate the rIK and rMSK
+ * rIK should be used to generate an authentication tag on the ERP message and
+ * rMSK should be used to derive a PMKSA.
+ * rIK, rMSK should be generated and keyname_nai, sequence number should be used
+ * as specified in IETF RFC 6696.
+ *
+ * When FILS shared key authentication is completed, driver needs to provide the
+ * below additional parameters to userspace.
+ *	%NL80211_ATTR_FILS_KEK - used for key renewal
+ *	%NL80211_ATTR_FILS_ERP_NEXT_SEQ_NUM - used in further EAP-RP exchanges
+ *	%NL80211_ATTR_PMKID - used to identify the PMKSA used/generated
+ *	%Nl80211_ATTR_PMK - used to update PMKSA cache in userspace
+ * The PMKSA can be maintained in userspace persistently so that it can be used
+ * later after reboots or wifi turn off/on also.
+ *
+ * %NL80211_ATTR_FILS_CACHE_ID is the cache identifier advertized by a FILS
+ * capable AP supporting PMK caching. It specifies the scope within which the
+ * PMKSAs are cached in an ESS. %NL80211_CMD_SET_PMKSA and
+ * %NL80211_CMD_DEL_PMKSA are enhanced to allow support for PMKSA caching based
+ * on FILS cache identifier. Additionally %NL80211_ATTR_PMK is used with
+ * %NL80211_SET_PMKSA to specify the PMK corresponding to a PMKSA for driver to
+ * use in a FILS shared key connection with PMKSA caching.
+ */
+
+/**
  * enum nl80211_commands - supported nl80211 commands
  *
  * @NL80211_CMD_UNSPEC: unspecified command to catch errors
@@ -370,10 +406,18 @@
  * @NL80211_CMD_NEW_SURVEY_RESULTS: survey data notification (as a reply to
  *	NL80211_CMD_GET_SURVEY and on the "scan" multicast group)
  *
- * @NL80211_CMD_SET_PMKSA: Add a PMKSA cache entry, using %NL80211_ATTR_MAC
- *	(for the BSSID) and %NL80211_ATTR_PMKID.
+ * @NL80211_CMD_SET_PMKSA: Add a PMKSA cache entry using %NL80211_ATTR_MAC
+ *	(for the BSSID), %NL80211_ATTR_PMKID, and optionally %NL80211_ATTR_PMK
+ *	(PMK is used for PTKSA derivation in case of FILS shared key offload) or
+ *	using %NL80211_ATTR_SSID, %NL80211_ATTR_FILS_CACHE_ID,
+ *	%NL80211_ATTR_PMKID, and %NL80211_ATTR_PMK in case of FILS
+ *	authentication where %NL80211_ATTR_FILS_CACHE_ID is the identifier
+ *	advertized by a FILS capable AP identifying the scope of PMKSA in an
+ *	ESS.
  * @NL80211_CMD_DEL_PMKSA: Delete a PMKSA cache entry, using %NL80211_ATTR_MAC
- *	(for the BSSID) and %NL80211_ATTR_PMKID.
+ *	(for the BSSID) and %NL80211_ATTR_PMKID or using %NL80211_ATTR_SSID,
+ *	%NL80211_ATTR_FILS_CACHE_ID, and %NL80211_ATTR_PMKID in case of FILS
+ *	authentication.
  * @NL80211_CMD_FLUSH_PMKSA: Flush all PMKSA cache entries.
  *
  * @NL80211_CMD_REG_CHANGE: indicates to userspace the regulatory domain
@@ -2012,6 +2056,31 @@ enum nl80211_commands {
  *	u32 attribute with an &enum nl80211_timeout_reason value. This is used,
  *	e.g., with %NL80211_CMD_CONNECT event.
  *
+ * @NL80211_ATTR_FILS_ERP_USERNAME: EAP Re-authentication Protocol (ERP)
+ *	username part of NAI used to refer keys rRK and rIK. This is used with
+ *	%NL80211_CMD_CONNECT.
+ *
+ * @NL80211_ATTR_FILS_ERP_REALM: EAP Re-authentication Protocol (ERP) realm part
+ *	of NAI specifying the domain name of the ER server. This is used with
+ *	%NL80211_CMD_CONNECT.
+ *
+ * @NL80211_ATTR_FILS_ERP_NEXT_SEQ_NUM: Unsigned 16-bit ERP next sequence number
+ *	to use in ERP messages. This is used in generating the FILS wrapped data
+ *	for FILS authentication and is used with %NL80211_CMD_CONNECT.
+ *
+ * @NL80211_ATTR_FILS_ERP_RRK: ERP re-authentication Root Key (rRK) for the
+ *	NAI specified by %NL80211_ATTR_FILS_ERP_USERNAME and
+ *	%NL80211_ATTR_FILS_ERP_REALM. This is used for generating rIK and rMSK
+ *	from successful FILS authentication and is used with
+ *	%NL80211_CMD_CONNECT.
+ *
+ * @NL80211_ATTR_FILS_CACHE_ID: A 2-octet identifier advertized by a FILS AP
+ *	identifying the scope of PMKSAs. This is used with
+ *	@NL80211_CMD_SET_PMKSA and @NL80211_CMD_DEL_PMKSA.
+ *
+ * @NL80211_ATTR_PMK: PMK for the PMKSA identified by %NL80211_ATTR_PMKID.
+ *	This is used with @NL80211_CMD_SET_PMKSA.
+ *
  * @NUM_NL80211_ATTR: total number of nl80211_attrs available
  * @NL80211_ATTR_MAX: highest attribute number currently defined
  * @__NL80211_ATTR_AFTER_LAST: internal use
@@ -2423,6 +2492,14 @@ enum nl80211_attrs {
 
 	NL80211_ATTR_TIMEOUT_REASON,
 
+	NL80211_ATTR_FILS_ERP_USERNAME,
+	NL80211_ATTR_FILS_ERP_REALM,
+	NL80211_ATTR_FILS_ERP_NEXT_SEQ_NUM,
+	NL80211_ATTR_FILS_ERP_RRK,
+	NL80211_ATTR_FILS_CACHE_ID,
+
+	NL80211_ATTR_PMK,
+
 	/* add attributes here, update the policy in nl80211.c */
 
 	__NL80211_ATTR_AFTER_LAST,
@@ -4759,6 +4836,8 @@ enum nl80211_feature_flags {
  * @NL80211_EXT_FEATURE_CQM_RSSI_LIST: With this driver the
  *	%NL80211_ATTR_CQM_RSSI_THOLD attribute accepts a list of zero or more
  *	RSSI threshold values to monitor rather than exactly one threshold.
+ * @NL80211_EXT_FEATURE_FILS_SK_OFFLOAD: Driver SME supports FILS shared key
+ *	authentication with %NL80211_CMD_CONNECT.
  *
  * @NUM_NL80211_EXT_FEATURES: number of extended features.
  * @MAX_NL80211_EXT_FEATURES: highest extended feature index.
@@ -4778,6 +4857,7 @@ enum nl80211_ext_feature_index {
 	NL80211_EXT_FEATURE_MGMT_TX_RANDOM_TA_CONNECTED,
 	NL80211_EXT_FEATURE_SCHED_SCAN_RELATIVE_RSSI,
 	NL80211_EXT_FEATURE_CQM_RSSI_LIST,
+	NL80211_EXT_FEATURE_FILS_SK_OFFLOAD,
 
 	/* add new features before the definition below */
 	NUM_NL80211_EXT_FEATURES,