FT: Maintain PMK-R1 for a connected STA

This is needed to allow PTK rekeying to be performed through 4-way
handshake in an association started through FT protocol.

Signed-off-by: Jouni Malinen <jouni@codeaurora.org>

src/ap/wpa_auth.c

@@ -1748,6 +1748,8 @@ int wpa_auth_sm_event(struct wpa_state_machine *sm, enum wpa_event event)
 		sm->pmk_len = 0;
 		os_memset(sm->xxkey, 0, sizeof(sm->xxkey));
 		sm->xxkey_len = 0;
+		os_memset(sm->pmk_r1, 0, sizeof(sm->pmk_r1));
+		sm->pmk_r1_len = 0;
 #endif /* CONFIG_IEEE80211R_AP */
 		break;
 	case WPA_REAUTH:

src/ap/wpa_auth_ft.c

@@ -2983,6 +2983,8 @@ pmk_r1_derived:
 	wpa_hexdump_key(MSG_DEBUG, "FT: Selected PMK-R1", pmk_r1, pmk_r1_len);
 	sm->pmk_r1_name_valid = 1;
 	os_memcpy(sm->pmk_r1_name, pmk_r1_name, WPA_PMK_NAME_LEN);
+	os_memcpy(sm->pmk_r1, pmk_r1, pmk_r1_len);
+	sm->pmk_r1_len = pmk_r1_len;
 
 	if (random_get_bytes(sm->ANonce, WPA_NONCE_LEN)) {
 		wpa_printf(MSG_DEBUG, "FT: Failed to get random data for "

src/ap/wpa_auth_i.h

@@ -119,6 +119,8 @@ struct wpa_state_machine {
 	u8 xxkey[PMK_LEN_MAX]; /* PSK or the second 256 bits of MSK, or the
 				* first 384 bits of MSK */
 	size_t xxkey_len;
+	u8 pmk_r1[PMK_LEN_MAX];
+	unsigned int pmk_r1_len;
 	u8 pmk_r1_name[WPA_PMK_NAME_LEN]; /* PMKR1Name derived from FT Auth
 					   * Request */
 	u8 r0kh_id[FT_R0KH_ID_MAX_LEN]; /* R0KH-ID from FT Auth Request */