The IEEE 802.11bi standard introduces the Enhanced Privacy Protection
Key Exchange (EPPKE) authentication protocol as specified in
"IEEE P802.11bi/D3.0, 12.16.9". This protocol requires passing a Key
Confirmation Key (KCK) from userspace to the driver to construct the
Message Integrity Code (MIC) for authentication frames.

Introduce a new netlink attribute, NL80211_ATTR_KEY_KCK, to allow
userspace to provide the KCK via the NL80211_CMD_AUTHENTICATE command.
This attribute is only present when the connection uses the EPPKE
authentication protocol.

Extend struct cfg80211_auth_request with a kck field to carry the key
from cfg80211 to the mac80211 layer.

Signed-off-by: Kavita Kavita <kavita.kavita@oss.qualcomm.com>
---
 include/net/cfg80211.h       |  4 ++++
 include/uapi/linux/nl80211.h |  8 ++++++++
 net/wireless/nl80211.c       | 10 ++++++++++
 3 files changed, 22 insertions(+)

diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index 38d201d4e676..6f02d2fdfc71 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -3187,6 +3187,8 @@ static inline const u8 *ieee80211_bss_get_ie(struct cfg80211_bss *bss, u8 id)
  * @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
+ * @kck: Key Confirmation Key for EPPKE Authentication.
+ * @kck_len: length of the KCK key for EPPKE Authentication.
  * @auth_data: Fields and elements in Authentication frames. This contains
  *	the authentication frame body (non-IE and IE data), excluding the
  *	Authentication algorithm number, i.e., starting at the Authentication
@@ -3209,6 +3211,8 @@ struct cfg80211_auth_request {
 	const u8 *key;
 	u8 key_len;
 	s8 key_idx;
+	const u8 *kck;
+	u8 kck_len;
 	const u8 *auth_data;
 	size_t auth_data_len;
 	s8 link_id;
diff --git a/include/uapi/linux/nl80211.h b/include/uapi/linux/nl80211.h
index f78f6e7c4ab7..d0008780ffcb 100644
--- a/include/uapi/linux/nl80211.h
+++ b/include/uapi/linux/nl80211.h
@@ -2981,6 +2981,12 @@ enum nl80211_commands {
  *	(e.g., EPPKE). If set, transmit key data to the driver for installation/
  *	removal/modification before the non-AP STA is associated.
  *
+ * @NL80211_ATTR_KEY_KCK: (Binary) Key Confirmation Key (KCK);
+ *	This attribute is used with %NL80211_CMD_AUTHENTICATE. In case of the
+ *	Enhanced Privacy Protection Key Exchange (EPPKE) authentication protocol
+ *	as specified in "IEEE P802.11bi/D3.0, 12.16.9", this attribute
+ *	is used for MIC calculation.
+ *
  * @NUM_NL80211_ATTR: total number of nl80211_attrs available
  * @NL80211_ATTR_MAX: highest attribute number currently defined
  * @__NL80211_ATTR_AFTER_LAST: internal use
@@ -3551,6 +3557,8 @@ enum nl80211_attrs {
 
 	NL80211_ATTR_KEY_PREASSOC,
 
+	NL80211_ATTR_KEY_KCK,
+
 	/* add attributes here, update the policy in nl80211.c */
 
 	__NL80211_ATTR_AFTER_LAST,
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index f297639b916f..d890d0f25191 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -933,6 +933,8 @@ static const struct nla_policy nl80211_policy[NUM_NL80211_ATTR] = {
 	[NL80211_ATTR_BSS_PARAM] = { .type = NLA_FLAG },
 	[NL80211_ATTR_S1G_PRIMARY_2MHZ] = { .type = NLA_FLAG },
 	[NL80211_ATTR_KEY_PREASSOC] = { .type = NLA_FLAG },
+	[NL80211_ATTR_KEY_KCK] = { .type = NLA_BINARY,
+				   .len = WLAN_MAX_KEY_LEN },
 };
 
 /* policy for the key attributes */
@@ -12034,6 +12036,14 @@ static int nl80211_authenticate(struct sk_buff *skb, struct genl_info *info)
 			if (!cfg80211_is_sae_akmp(akm_suite))
 				return -EINVAL;
 		}
+
+		if (auth_trans == 3) {
+			if (!info->attrs[NL80211_ATTR_KEY_KCK])
+				return -EINVAL;
+
+			req.kck_len = nla_len(info->attrs[NL80211_ATTR_KEY_KCK]);
+			req.kck = nla_data(info->attrs[NL80211_ATTR_KEY_KCK]);
+		}
 	}
 
 	local_state_change = !!info->attrs[NL80211_ATTR_LOCAL_STATE_CHANGE];
-- 
2.34.1