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 selecting a
hash algorithm such as SHA-256, SHA-384, or SHA-512 to use for
Message Integrity Code (MIC) computation and for generating the hash
of the Authentication frame.

Add a new netlink attribute, NL80211_ATTR_HASH_ALG, to allow userspace
to provide the hash algorithm 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 hash_alg field to carry the
hash algorithm from cfg80211 to the mac80211 layer.

Signed-off-by: Kavita Kavita <kavita.kavita@oss.qualcomm.com>
---
 include/net/cfg80211.h       |  3 +++
 include/uapi/linux/nl80211.h | 36 ++++++++++++++++++++++++++++++++++++
 net/wireless/nl80211.c       |  9 +++++++++
 3 files changed, 48 insertions(+)

diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index 6f02d2fdfc71..8f2ad094779f 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -3200,6 +3200,8 @@ static inline const u8 *ieee80211_bss_get_ie(struct cfg80211_bss *bss, u8 id)
  *	given an MLD address) by the driver
  * @ap_mld_addr: AP MLD address in case of authentication request with
  *	an AP MLD, valid iff @link_id >= 0
+ * @hash_alg: Hash algorithm defined in @enum nl80211_hash_alg used in EPPKE
+ *	Authentication.
  */
 struct cfg80211_auth_request {
 	struct cfg80211_bss *bss;
@@ -3217,6 +3219,7 @@ struct cfg80211_auth_request {
 	size_t auth_data_len;
 	s8 link_id;
 	const u8 *ap_mld_addr;
+	u32 hash_alg;
 };
 
 /**
diff --git a/include/uapi/linux/nl80211.h b/include/uapi/linux/nl80211.h
index d0008780ffcb..0074fccd4b51 100644
--- a/include/uapi/linux/nl80211.h
+++ b/include/uapi/linux/nl80211.h
@@ -2987,6 +2987,13 @@ enum nl80211_commands {
  *	as specified in "IEEE P802.11bi/D3.0, 12.16.9", this attribute
  *	is used for MIC calculation.
  *
+ * @NL80211_ATTR_HASH_ALG: (u32) Hash algorithm used both for Message Integrity
+ *	Code (MIC) computation and for generating the hash of the Authentication
+ *	frame in the Enhanced Privacy Protection Key Exchange (EPPKE)
+ *	authentication protocol as specified in "IEEE P802.11bi/D3.0, 12.16.9".
+ *	This attribute is used with %NL80211_CMD_AUTHENTICATE.
+ *	See &enum nl80211_hash_alg for details.
+ *
  * @NUM_NL80211_ATTR: total number of nl80211_attrs available
  * @NL80211_ATTR_MAX: highest attribute number currently defined
  * @__NL80211_ATTR_AFTER_LAST: internal use
@@ -3559,6 +3566,8 @@ enum nl80211_attrs {
 
 	NL80211_ATTR_KEY_KCK,
 
+	NL80211_ATTR_HASH_ALG,
+
 	/* add attributes here, update the policy in nl80211.c */
 
 	__NL80211_ATTR_AFTER_LAST,
@@ -8463,4 +8472,31 @@ enum nl80211_nan_capabilities {
 	NL80211_NAN_CAPABILITIES_MAX = __NL80211_NAN_CAPABILITIES_LAST - 1,
 };
 
+/**
+ * enum nl80211_hash_alg - Hash algorithms used in EPPKE
+ *
+ * @__NL80211_HASH_ALG_INVALID: invalid, not used
+ * @NL80211_HASH_ALG_SHA256: SHA-256
+ * @NL80211_HASH_ALG_SHA384: SHA-384
+ * @NL80211_HASH_ALG_SHA512: SHA-512
+ * @__NL80211_HASH_ALG_LAST: internal use
+ * @NL80211_HASH_ALG_MAX: highest hash algorithm number currently defined
+ *
+ * These values are used with %NL80211_ATTR_HASH_ALG to select the hash
+ * algorithm used both for computing the MIC and for generating the hash
+ * of the Authentication frame in the EPPKE authentication protocol.
+ */
+
+enum nl80211_hash_alg {
+	__NL80211_HASH_ALG_INVALID,
+
+	NL80211_HASH_ALG_SHA256,
+	NL80211_HASH_ALG_SHA384,
+	NL80211_HASH_ALG_SHA512,
+
+	/* keep last */
+	__NL80211_HASH_ALG_LAST,
+	NL80211_HASH_ALG_MAX = __NL80211_HASH_ALG_LAST - 1
+};
+
 #endif /* __LINUX_NL80211_H */
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index d890d0f25191..c83252cfc0bb 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -935,6 +935,9 @@ static const struct nla_policy nl80211_policy[NUM_NL80211_ATTR] = {
 	[NL80211_ATTR_KEY_PREASSOC] = { .type = NLA_FLAG },
 	[NL80211_ATTR_KEY_KCK] = { .type = NLA_BINARY,
 				   .len = WLAN_MAX_KEY_LEN },
+	[NL80211_ATTR_HASH_ALG] = { .type = NLA_U32,
+				    .min = NL80211_HASH_ALG_SHA256,
+				    .max = NL80211_HASH_ALG_MAX },
 };
 
 /* policy for the key attributes */
@@ -12035,6 +12038,12 @@ static int nl80211_authenticate(struct sk_buff *skb, struct genl_info *info)
 			akm_suite = get_unaligned_be32(akm_list);
 			if (!cfg80211_is_sae_akmp(akm_suite))
 				return -EINVAL;
+
+			if (!info->attrs[NL80211_ATTR_HASH_ALG])
+				return -EINVAL;
+
+			req.hash_alg =
+				nla_get_u32(info->attrs[NL80211_ATTR_HASH_ALG]);
 		}
 
 		if (auth_trans == 3) {
-- 
2.34.1