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>

3 files changed, 151 insertions, 5 deletions

diff --git a/include/linux/ieee80211.h b/include/linux/ieee80211.h
index 22bf0676d928..294fa6273a62 100644
--- a/include/linux/ieee80211.h
+++ b/include/linux/ieee80211.h
@@ -1723,6 +1723,9 @@ enum ieee80211_statuscode {
 	WLAN_STATUS_REJECT_DSE_BAND = 96,
 	WLAN_STATUS_DENIED_WITH_SUGGESTED_BAND_AND_CHANNEL = 99,
 	WLAN_STATUS_DENIED_DUE_TO_SPECTRUM_MANAGEMENT = 103,
+	/* 802.11ai */
+	WLAN_STATUS_FILS_AUTHENTICATION_FAILURE = 108,
+	WLAN_STATUS_UNKNOWN_AUTHENTICATION_SERVER = 109,
 };
 
 
@@ -2104,6 +2107,12 @@ enum ieee80211_key_len {
 #define FILS_NONCE_LEN			16
 #define FILS_MAX_KEK_LEN		64
 
+#define FILS_ERP_MAX_USERNAME_LEN	16
+#define FILS_ERP_MAX_REALM_LEN		253
+#define FILS_ERP_MAX_RRK_LEN		64
+
+#define PMK_MAX_LEN			48
+
 /* Public action codes */
 enum ieee80211_pub_actioncode {
 	WLAN_PUB_ACTION_EXT_CHANSW_ANN = 4,
@@ -2355,6 +2364,10 @@ enum ieee80211_sa_query_action {
 #define WLAN_AKM_SUITE_TDLS		SUITE(0x000FAC, 7)
 #define WLAN_AKM_SUITE_SAE		SUITE(0x000FAC, 8)
 #define WLAN_AKM_SUITE_FT_OVER_SAE	SUITE(0x000FAC, 9)
+#define WLAN_AKM_SUITE_FILS_SHA256	SUITE(0x000FAC, 14)
+#define WLAN_AKM_SUITE_FILS_SHA384	SUITE(0x000FAC, 15)
+#define WLAN_AKM_SUITE_FT_FILS_SHA256	SUITE(0x000FAC, 16)
+#define WLAN_AKM_SUITE_FT_FILS_SHA384	SUITE(0x000FAC, 17)
 
 #define WLAN_MAX_KEY_LEN		32
 
diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index da12d5b86e1b..042137d7d226 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -2073,6 +2073,19 @@ struct cfg80211_bss_selection {
  *	the BSSID of the current association, i.e., to the value that is
  *	included in the Current AP address field of the Reassociation Request
  *	frame.
+ * @fils_erp_username: EAP re-authentication protocol (ERP) username part of the
+ *	NAI or %NULL if not specified. This is used to construct FILS wrapped
+ *	data IE.
+ * @fils_erp_username_len: Length of @fils_erp_username in octets.
+ * @fils_erp_realm: EAP re-authentication protocol (ERP) realm part of NAI or
+ *	%NULL if not specified. This specifies the domain name of ER server and
+ *	is used to construct FILS wrapped data IE.
+ * @fils_erp_realm_len: Length of @fils_erp_realm in octets.
+ * @fils_erp_next_seq_num: The next sequence number to use in the FILS ERP
+ *	messages. This is also used to construct FILS wrapped data IE.
+ * @fils_erp_rrk: ERP re-authentication Root Key (rRK) used to derive additional
+ *	keys in FILS or %NULL if not specified.
+ * @fils_erp_rrk_len: Length of @fils_erp_rrk in octets.
  */
 struct cfg80211_connect_params {
 	struct ieee80211_channel *channel;
@@ -2098,6 +2111,13 @@ struct cfg80211_connect_params {
 	bool pbss;
 	struct cfg80211_bss_selection bss_select;
 	const u8 *prev_bssid;
+	const u8 *fils_erp_username;
+	size_t fils_erp_username_len;
+	const u8 *fils_erp_realm;
+	size_t fils_erp_realm_len;
+	u16 fils_erp_next_seq_num;
+	const u8 *fils_erp_rrk;
+	size_t fils_erp_rrk_len;
 };
 
 /**
@@ -2136,12 +2156,27 @@ enum wiphy_params_flags {
  * This structure is passed to the set/del_pmksa() method for PMKSA
  * caching.
  *
- * @bssid: The AP's BSSID.
- * @pmkid: The PMK material itself.
+ * @bssid: The AP's BSSID (may be %NULL).
+ * @pmkid: The identifier to refer a PMKSA.
+ * @pmk: The PMK for the PMKSA identified by @pmkid. This is used for key
+ *	derivation by a FILS STA. Otherwise, %NULL.
+ * @pmk_len: Length of the @pmk. The length of @pmk can differ depending on
+ *	the hash algorithm used to generate this.
+ * @ssid: SSID to specify the ESS within which a PMKSA is valid when using FILS
+ *	cache identifier (may be %NULL).
+ * @ssid_len: Length of the @ssid in octets.
+ * @cache_id: 2-octet cache identifier advertized by a FILS AP identifying the
+ *	scope of PMKSA. This is valid only if @ssid_len is non-zero (may be
+ *	%NULL).
  */
 struct cfg80211_pmksa {
 	const u8 *bssid;
 	const u8 *pmkid;
+	const u8 *pmk;
+	size_t pmk_len;
+	const u8 *ssid;
+	size_t ssid_len;
+	const u8 *cache_id;
 };
 
 /**
@@ -5153,6 +5188,17 @@ static inline void cfg80211_testmode_event(struct sk_buff *skb, gfp_t gfp)
  * @req_ie_len: Association request IEs length
  * @resp_ie: Association response IEs (may be %NULL)
  * @resp_ie_len: Association response IEs length
+ * @fils_kek: KEK derived from a successful FILS connection (may be %NULL)
+ * @fils_kek_len: Length of @fils_kek in octets
+ * @update_erp_next_seq_num: Boolean value to specify whether the value in
+ *	@fils_erp_next_seq_num is valid.
+ * @fils_erp_next_seq_num: The next sequence number to use in ERP message in
+ *	FILS Authentication. This value should be specified irrespective of the
+ *	status for a FILS connection.
+ * @pmk: A new PMK if derived from a successful FILS connection (may be %NULL).
+ * @pmk_len: Length of @pmk in octets
+ * @pmkid: A new PMKID if derived from a successful FILS connection or the PMKID
+ *	used for this FILS connection (may be %NULL).
  * @timeout_reason: Reason for connection timeout. This is used when the
  *	connection fails due to a timeout instead of an explicit rejection from
  *	the AP. %NL80211_TIMEOUT_UNSPECIFIED is used when the timeout reason is
@@ -5168,6 +5214,13 @@ struct cfg80211_connect_resp_params {
 	size_t req_ie_len;
 	const u8 *resp_ie;
 	size_t resp_ie_len;
+	const u8 *fils_kek;
+	size_t fils_kek_len;
+	bool update_erp_next_seq_num;
+	u16 fils_erp_next_seq_num;
+	const u8 *pmk;
+	size_t pmk_len;
+	const u8 *pmkid;
 	enum nl80211_timeout_reason timeout_reason;
 };
 
diff --git a/include/uapi/linux/nl80211.h b/include/uapi/linux/nl80211.h
index cd4dfef58fab..6095a6c4c412 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,