brcmfmac: support 4-way handshake offloading for WPA/WPA2-PSK

The firmware may have supplicant code built-in. This is detected
by the driver and indicated in the wiphy features flags. User-space
can use this flag to determine whether or not to provide the
pre-shared key material in the nl80211 CONNECT command.

Reviewed-by: Gautam (Gautam Kumar) Shukla <gautams@broadcom.com>
Reviewed-by: Hante Meuleman <meuleman@broadcom.com>
Reviewed-by: Pieter-Paul Giesberts <pieterpg@broadcom.com>
Signed-off-by: Arend van Spriel <arend.vanspriel@broadcom.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c

@@ -1357,6 +1357,27 @@ static u16 brcmf_map_fw_linkdown_reason(const struct brcmf_event_msg *e)
 	return reason;
 }
 
+static int brcmf_set_pmk(struct brcmf_if *ifp, const u8 *pmk_data, u16 pmk_len)
+{
+	struct brcmf_wsec_pmk_le pmk;
+	int i, err;
+
+	/* convert to firmware key format */
+	pmk.key_len = cpu_to_le16(pmk_len << 1);
+	pmk.flags = cpu_to_le16(BRCMF_WSEC_PASSPHRASE);
+	for (i = 0; i < pmk_len; i++)
+		snprintf(&pmk.key[2 * i], 3, "%02x", pmk_data[i]);
+
+	/* store psk in firmware */
+	err = brcmf_fil_cmd_data_set(ifp, BRCMF_C_SET_WSEC_PMK,
+				     &pmk, sizeof(pmk));
+	if (err < 0)
+		brcmf_err("failed to change PSK in firmware (len=%u)\n",
+			  pmk_len);
+
+	return err;
+}
+
 static void brcmf_link_down(struct brcmf_cfg80211_vif *vif, u16 reason)
 {
 	struct brcmf_cfg80211_info *cfg = wiphy_to_cfg(vif->wdev.wiphy);
@@ -1379,6 +1400,10 @@ static void brcmf_link_down(struct brcmf_cfg80211_vif *vif, u16 reason)
 	clear_bit(BRCMF_VIF_STATUS_CONNECTING, &vif->sme_state);
 	clear_bit(BRCMF_SCAN_STATUS_SUPPRESS, &cfg->scan_status);
 	brcmf_btcoex_set_mode(vif, BRCMF_BTCOEX_ENABLED, 0);
+	if (vif->profile.use_fwsup != BRCMF_PROFILE_FWSUP_NONE) {
+		brcmf_set_pmk(vif->ifp, NULL, 0);
+		vif->profile.use_fwsup = BRCMF_PROFILE_FWSUP_NONE;
+	}
 	brcmf_dbg(TRACE, "Exit\n");
 }
 
@@ -2012,6 +2037,23 @@ brcmf_cfg80211_connect(struct wiphy *wiphy, struct net_device *ndev,
 		goto done;
 	}
 
+	if (sme->crypto.psk) {
+		brcmf_dbg(INFO, "using PSK offload\n");
+
+		/* enable firmware supplicant for this interface */
+		err = brcmf_fil_iovar_int_set(ifp, "sup_wpa", 1);
+		if (err < 0) {
+			brcmf_err("failed to enable fw supplicant\n");
+			goto done;
+		}
+		ifp->vif->profile.use_fwsup = BRCMF_PROFILE_FWSUP_PSK;
+
+		err = brcmf_set_pmk(ifp, sme->crypto.psk,
+				    BRCMF_WSEC_MAX_PSK_LEN);
+		if (err)
+			goto done;
+	}
+
 	/* Join with specific BSSID and cached SSID
 	 * If SSID is zero join based on BSSID only
 	 */
@@ -5247,16 +5289,30 @@ void brcmf_cfg80211_free_netdev(struct net_device *ndev)
 		brcmf_free_vif(vif);
 }
 
-static bool brcmf_is_linkup(const struct brcmf_event_msg *e)
+static bool brcmf_is_linkup(struct brcmf_cfg80211_vif *vif,
+			    const struct brcmf_event_msg *e)
 {
 	u32 event = e->event_code;
 	u32 status = e->status;
 
+	if (event == BRCMF_E_PSK_SUP &&
+	    status == BRCMF_E_STATUS_FWSUP_COMPLETED)
+		set_bit(BRCMF_VIF_STATUS_EAP_SUCCESS, &vif->sme_state);
 	if (event == BRCMF_E_SET_SSID && status == BRCMF_E_STATUS_SUCCESS) {
 		brcmf_dbg(CONN, "Processing set ssid\n");
-		return true;
+		memcpy(vif->profile.bssid, e->addr, ETH_ALEN);
+		if (vif->profile.use_fwsup != BRCMF_PROFILE_FWSUP_PSK)
+			return true;
+
+		set_bit(BRCMF_VIF_STATUS_ASSOC_SUCCESS, &vif->sme_state);
 	}
 
+	if (test_bit(BRCMF_VIF_STATUS_EAP_SUCCESS, &vif->sme_state) &&
+	    test_bit(BRCMF_VIF_STATUS_ASSOC_SUCCESS, &vif->sme_state)) {
+		clear_bit(BRCMF_VIF_STATUS_EAP_SUCCESS, &vif->sme_state);
+		clear_bit(BRCMF_VIF_STATUS_ASSOC_SUCCESS, &vif->sme_state);
+		return true;
+	}
 	return false;
 }
 
@@ -5291,6 +5347,13 @@ static bool brcmf_is_nonetwork(struct brcmf_cfg80211_info *cfg,
 		return true;
 	}
 
+	if (event == BRCMF_E_PSK_SUP &&
+	    status != BRCMF_E_STATUS_FWSUP_COMPLETED) {
+		brcmf_dbg(CONN, "Processing failed supplicant state: %u\n",
+			  status);
+		return true;
+	}
+
 	return false;
 }
 
@@ -5448,7 +5511,6 @@ brcmf_bss_connect_done(struct brcmf_cfg80211_info *cfg,
 			       &ifp->vif->sme_state)) {
 		if (completed) {
 			brcmf_get_assoc_ies(cfg, ifp);
-			memcpy(profile->bssid, e->addr, ETH_ALEN);
 			brcmf_update_bss_info(cfg, ifp);
 			set_bit(BRCMF_VIF_STATUS_CONNECTED,
 				&ifp->vif->sme_state);
@@ -5527,7 +5589,7 @@ brcmf_notify_connect_status(struct brcmf_if *ifp,
 
 	if (brcmf_is_apmode(ifp->vif)) {
 		err = brcmf_notify_connect_status_ap(cfg, ndev, e, data);
-	} else if (brcmf_is_linkup(e)) {
+	} else if (brcmf_is_linkup(ifp->vif, e)) {
 		brcmf_dbg(CONN, "Linkup\n");
 		if (brcmf_is_ibssmode(ifp->vif)) {
 			brcmf_inform_ibss(cfg, ndev, e->addr);
@@ -5695,6 +5757,8 @@ static void brcmf_register_event_handlers(struct brcmf_cfg80211_info *cfg)
 			    brcmf_p2p_notify_action_tx_complete);
 	brcmf_fweh_register(cfg->pub, BRCMF_E_ACTION_FRAME_OFF_CHAN_COMPLETE,
 			    brcmf_p2p_notify_action_tx_complete);
+	brcmf_fweh_register(cfg->pub, BRCMF_E_PSK_SUP,
+			    brcmf_notify_connect_status);
 }
 
 static void brcmf_deinit_priv_mem(struct brcmf_cfg80211_info *cfg)
@@ -6491,6 +6555,9 @@ static int brcmf_setup_wiphy(struct wiphy *wiphy, struct brcmf_if *ifp)
 		wiphy->flags |= WIPHY_FLAG_SUPPORTS_TDLS;
 	if (!ifp->drvr->settings->roamoff)
 		wiphy->flags |= WIPHY_FLAG_SUPPORTS_FW_ROAM;
+	if (brcmf_feat_is_enabled(ifp, BRCMF_FEAT_FWSUP))
+		wiphy_ext_feature_set(wiphy,
+				      NL80211_EXT_FEATURE_4WAY_HANDSHAKE_STA_PSK);
 	wiphy->mgmt_stypes = brcmf_txrx_stypes;
 	wiphy->max_remain_on_channel_duration = 5000;
 	if (brcmf_feat_is_enabled(ifp, BRCMF_FEAT_PNO)) {

drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.h

@@ -115,6 +115,11 @@ struct brcmf_cfg80211_security {
 	u32 cipher_group;
 };
 
+enum brcmf_profile_fwsup {
+	BRCMF_PROFILE_FWSUP_NONE,
+	BRCMF_PROFILE_FWSUP_PSK
+};
+
 /**
  * struct brcmf_cfg80211_profile - profile information.
  *
@@ -126,6 +131,7 @@ struct brcmf_cfg80211_profile {
 	u8 bssid[ETH_ALEN];
 	struct brcmf_cfg80211_security sec;
 	struct brcmf_wsec_key key[BRCMF_MAX_DEFAULT_KEYS];
+	enum brcmf_profile_fwsup use_fwsup;
 };
 
 /**
@@ -133,16 +139,20 @@ struct brcmf_cfg80211_profile {
  *
  * @BRCMF_VIF_STATUS_READY: ready for operation.
  * @BRCMF_VIF_STATUS_CONNECTING: connect/join in progress.
- * @BRCMF_VIF_STATUS_CONNECTED: connected/joined succesfully.
+ * @BRCMF_VIF_STATUS_CONNECTED: connected/joined successfully.
  * @BRCMF_VIF_STATUS_DISCONNECTING: disconnect/disable in progress.
  * @BRCMF_VIF_STATUS_AP_CREATED: AP operation started.
+ * @BRCMF_VIF_STATUS_EAP_SUCCUSS: EAPOL handshake successful.
+ * @BRCMF_VIF_STATUS_ASSOC_SUCCESS: successful SET_SSID received.
  */
 enum brcmf_vif_status {
 	BRCMF_VIF_STATUS_READY,
 	BRCMF_VIF_STATUS_CONNECTING,
 	BRCMF_VIF_STATUS_CONNECTED,
 	BRCMF_VIF_STATUS_DISCONNECTING,
-	BRCMF_VIF_STATUS_AP_CREATED
+	BRCMF_VIF_STATUS_AP_CREATED,
+	BRCMF_VIF_STATUS_EAP_SUCCESS,
+	BRCMF_VIF_STATUS_ASSOC_SUCCESS,
 };
 
 /**

drivers/net/wireless/broadcom/brcm80211/brcmfmac/feature.c

@@ -195,6 +195,7 @@ void brcmf_feat_attach(struct brcmf_pub *drvr)
 			  drvr->settings->feature_disable);
 		ifp->drvr->feat_flags &= ~drvr->settings->feature_disable;
 	}
+	brcmf_feat_iovar_int_get(ifp, BRCMF_FEAT_FWSUP, "sup_wpa");
 
 	/* set chip related quirks */
 	switch (drvr->bus_if->chip) {

drivers/net/wireless/broadcom/brcm80211/brcmfmac/feature.h

@@ -32,6 +32,7 @@
  * WOWL_ARP_ND: ARP and Neighbor Discovery offload support during WOWL.
  * MFP: 802.11w Management Frame Protection.
  * GSCAN: enhanced scan offload feature.
+ * FWSUP: Firmware supplicant.
  */
 #define BRCMF_FEAT_LIST \
 	BRCMF_FEAT_DEF(MBSS) \
@@ -46,7 +47,8 @@
 	BRCMF_FEAT_DEF(WOWL_GTK) \
 	BRCMF_FEAT_DEF(WOWL_ARP_ND) \
 	BRCMF_FEAT_DEF(MFP) \
-	BRCMF_FEAT_DEF(GSCAN)
+	BRCMF_FEAT_DEF(GSCAN) \
+	BRCMF_FEAT_DEF(FWSUP)
 
 /*
  * Quirks:

drivers/net/wireless/broadcom/brcm80211/brcmfmac/fweh.h

@@ -142,6 +142,16 @@ enum brcmf_fweh_event_code {
 #define BRCMF_E_STATUS_CS_ABORT			15
 #define BRCMF_E_STATUS_ERROR			16
 
+/* status field values for PSK_SUP event */
+#define BRCMF_E_STATUS_FWSUP_WAIT_M1		4
+#define BRCMF_E_STATUS_FWSUP_PREP_M2		5
+#define BRCMF_E_STATUS_FWSUP_COMPLETED		6
+#define BRCMF_E_STATUS_FWSUP_TIMEOUT		7
+#define BRCMF_E_STATUS_FWSUP_WAIT_M3		8
+#define BRCMF_E_STATUS_FWSUP_PREP_M4		9
+#define BRCMF_E_STATUS_FWSUP_WAIT_G1		10
+#define BRCMF_E_STATUS_FWSUP_PREP_G2		11
+
 /* reason field values in struct brcmf_event_msg */
 #define BRCMF_E_REASON_INITIAL_ASSOC		0
 #define BRCMF_E_REASON_LOW_RSSI			1
@@ -161,6 +171,26 @@ enum brcmf_fweh_event_code {
 #define BRCMF_E_REASON_TDLS_PEER_CONNECTED	1
 #define BRCMF_E_REASON_TDLS_PEER_DISCONNECTED	2
 
+/* reason field values for PSK_SUP event */
+#define BRCMF_E_REASON_FWSUP_OTHER		0
+#define BRCMF_E_REASON_FWSUP_DECRYPT_KEY_DATA	1
+#define BRCMF_E_REASON_FWSUP_BAD_UCAST_WEP128	2
+#define BRCMF_E_REASON_FWSUP_BAD_UCAST_WEP40	3
+#define BRCMF_E_REASON_FWSUP_UNSUP_KEY_LEN	4
+#define BRCMF_E_REASON_FWSUP_PW_KEY_CIPHER	5
+#define BRCMF_E_REASON_FWSUP_MSG3_TOO_MANY_IE	6
+#define BRCMF_E_REASON_FWSUP_MSG3_IE_MISMATCH	7
+#define BRCMF_E_REASON_FWSUP_NO_INSTALL_FLAG	8
+#define BRCMF_E_REASON_FWSUP_MSG3_NO_GTK	9
+#define BRCMF_E_REASON_FWSUP_GRP_KEY_CIPHER	10
+#define BRCMF_E_REASON_FWSUP_GRP_MSG1_NO_GTK	11
+#define BRCMF_E_REASON_FWSUP_GTK_DECRYPT_FAIL	12
+#define BRCMF_E_REASON_FWSUP_SEND_FAIL		13
+#define BRCMF_E_REASON_FWSUP_DEAUTH		14
+#define BRCMF_E_REASON_FWSUP_WPA_PSK_TMO	15
+#define BRCMF_E_REASON_FWSUP_WPA_PSK_M1_TMO	16
+#define BRCMF_E_REASON_FWSUP_WPA_PSK_M3_TMO	17
+
 /* action field values for brcmf_ifevent */
 #define BRCMF_E_IF_ADD				1
 #define BRCMF_E_IF_DEL				2

drivers/net/wireless/broadcom/brcm80211/brcmfmac/fwil.h

@@ -85,6 +85,7 @@
 #define BRCMF_C_SET_SCAN_PASSIVE_TIME		258
 #define BRCMF_C_GET_VAR				262
 #define BRCMF_C_SET_VAR				263
+#define BRCMF_C_SET_WSEC_PMK			268
 
 s32 brcmf_fil_cmd_data_set(struct brcmf_if *ifp, u32 cmd, void *data, u32 len);
 s32 brcmf_fil_cmd_data_get(struct brcmf_if *ifp, u32 cmd, void *data, u32 len);

drivers/net/wireless/broadcom/brcm80211/brcmfmac/fwil_types.h

@@ -45,6 +45,9 @@
 #define BRCMF_SCAN_PARAMS_COUNT_MASK	0x0000ffff
 #define BRCMF_SCAN_PARAMS_NSSID_SHIFT	16
 
+#define BRCMF_WSEC_MAX_PSK_LEN		32
+#define	BRCMF_WSEC_PASSPHRASE		BIT(0)
+
 /* primary (ie tx) key */
 #define BRCMF_PRIMARY_KEY		(1 << 1)
 #define DOT11_BSSTYPE_ANY		2
@@ -470,6 +473,19 @@ struct brcmf_wsec_key_le {
 	u8 ea[ETH_ALEN];	/* per station */
 };
 
+/**
+ * struct brcmf_wsec_pmk_le - firmware pmk material.
+ *
+ * @key_len: number of octets in key material.
+ * @flags: key handling qualifiers.
+ * @key: PMK key material.
+ */
+struct brcmf_wsec_pmk_le {
+	__le16  key_len;
+	__le16  flags;
+	u8 key[2 * BRCMF_WSEC_MAX_PSK_LEN + 1];
+};
+
 /* Used to get specific STA parameters */
 struct brcmf_scb_val_le {
 	__le32 val;